The major metabolite in neutrophil polymorphonuclear leukocytes. It stimulates polymorphonuclear cell function (degranulation, formation of oxygen-centered free radicals, arachidonic acid release, and metabolism). (From Dictionary of Prostaglandins and Related Compounds, 1990)
(2S-(2 alpha,3 beta(1E,3E,5Z,8Z)))-3-(1,3,5,8-Tetradecatetraenyl)oxiranebutanoic acid. An unstable allylic epoxide, formed from the immediate precursor 5-HPETE via the stereospecific removal of a proton at C-10 and dehydration. Its biological actions are determined primarily by its metabolites, i.e., LEUKOTRIENE B4 and cysteinyl-leukotrienes. Alternatively, leukotriene A4 is converted into LEUKOTRIENE C4 by glutathione-S-transferase or into 5,6-di-HETE by the epoxide-hydrolase. (From Dictionary of Prostaglandins and Related Compounds, 1990)
A class of cell surface leukotriene receptors with a preference for leukotriene B4. Leukotriene B4 receptor activation influences chemotaxis, chemokinesis, adherence, enzyme release, oxidative bursts, and degranulation in polymorphonuclear leukocytes. There are at least two subtypes of these receptors. Some actions are mediated through the inositol phosphate and diacylglycerol second messenger systems.
Cell-surface receptors that bind LEUKOTRIENES with high affinity and trigger intracellular changes influencing the behavior of cells. The leukotriene receptor subtypes have been tentatively named according to their affinities for the endogenous leukotrienes LTB4; LTC4; LTD4; and LTE4.
The conjugation product of LEUKOTRIENE A4 and glutathione. It is the major arachidonic acid metabolite in macrophages and human mast cells as well as in antigen-sensitized lung tissue. It stimulates mucus secretion in the lung, and produces contractions of nonvascular and some VASCULAR SMOOTH MUSCLE. (From Dictionary of Prostaglandins and Related Compounds, 1990)
A class of drugs designed to prevent leukotriene synthesis or activity by blocking binding at the receptor level.
A biologically active principle of SRS-A that is formed from LEUKOTRIENE D4 via a peptidase reaction that removes the glycine residue. The biological actions of LTE4 are similar to LTC4 and LTD4. (From Dictionary of Prostaglandins and Related Compounds, 1990)
One of the biologically active principles of SRS-A. It is generated from LEUKOTRIENE C4 after partial hydrolysis of the peptide chain, i.e., cleavage of the gamma-glutamyl portion. Its biological actions include stimulation of vascular and nonvascular smooth muscle, and increases in vascular permeability. (From Dictionary of Prostaglandins and Related Compounds, 1990)
A group of LEUKOTRIENES; (LTC4; LTD4; and LTE4) that is the major mediator of BRONCHOCONSTRICTION; HYPERSENSITIVITY; and other allergic reactions. Earlier studies described a "slow-reacting substance of ANAPHYLAXIS" released from lung by cobra venom or after anaphylactic shock. The relationship between SRS-A leukotrienes was established by UV which showed the presence of the conjugated triene. (From Merck Index, 11th ed)
A family of biologically active compounds derived from arachidonic acid by oxidative metabolism through the 5-lipoxygenase pathway. They participate in host defense reactions and pathophysiological conditions such as immediate hypersensitivity and inflammation. They have potent actions on many essential organs and systems, including the cardiovascular, pulmonary, and central nervous system as well as the gastrointestinal tract and the immune system.
An enzyme that catalyzes the oxidation of arachidonic acid to yield 5-hydroperoxyarachidonate (5-HPETE) which is rapidly converted by a peroxidase to 5-hydroxy-6,8,11,14-eicosatetraenoate (5-HETE). The 5-hydroperoxides are preferentially formed in leukocytes.
Enzymes that catalyze reversibly the formation of an epoxide or arene oxide from a glycol or aromatic diol, respectively.
Compounds that bind to and inhibit that enzymatic activity of LIPOXYGENASES. Included under this category are inhibitors that are specific for lipoxygenase subtypes and act to reduce the production of LEUKOTRIENES.
Scaffolding proteins that play an important role in the localization and activation of 5-LIPOXYGENASE.
Eicosatetraenoic acids substituted in any position by one or more hydroxy groups. They are important intermediates in a series of biosynthetic processes leading from arachidonic acid to a number of biologically active compounds such as prostaglandins, thromboxanes, and leukotrienes.
Granular leukocytes having a nucleus with three to five lobes connected by slender threads of chromatin, and cytoplasm containing fine inconspicuous granules and stainable by neutral dyes.
Arachidonic acids are polyunsaturated fatty acids, specifically a type of omega-6 fatty acid, that are essential for human nutrition and play crucial roles in various biological processes, including inflammation, immunity, and cell signaling. They serve as precursors to eicosanoids, which are hormone-like substances that mediate a wide range of physiological responses.
Enzymes catalyzing the oxidation of arachidonic acid to hydroperoxyarachidonates. These products are then rapidly converted by a peroxidase to hydroxyeicosatetraenoic acids. The positional specificity of the enzyme reaction varies from tissue to tissue. The final lipoxygenase pathway leads to the leukotrienes. EC 1.13.11.- .
Quinolines are heterocyclic aromatic organic compounds consisting of a two-nitrogened benzene ring fused to a pyridine ring, which have been synthesized and used as building blocks for various medicinal drugs, particularly antibiotics and antimalarials.
An ionophorous, polyether antibiotic from Streptomyces chartreusensis. It binds and transports CALCIUM and other divalent cations across membranes and uncouples oxidative phosphorylation while inhibiting ATPase of rat liver mitochondria. The substance is used mostly as a biochemical tool to study the role of divalent cations in various biological systems.
An unsaturated, essential fatty acid. It is found in animal and human fat as well as in the liver, brain, and glandular organs, and is a constituent of animal phosphatides. It is formed by the synthesis from dietary linoleic acid and is a precursor in the biosynthesis of prostaglandins, thromboxanes, and leukotrienes.
An enzyme of the oxidoreductase class primarily found in PLANTS. It catalyzes reactions between linoleate and other fatty acids and oxygen to form hydroperoxy-fatty acid derivatives.
A class of compounds named after and generally derived from C20 fatty acids (EICOSANOIC ACIDS) that includes PROSTAGLANDINS; LEUKOTRIENES; THROMBOXANES, and HYDROXYEICOSATETRAENOIC ACIDS. They have hormone-like effects mediated by specialized receptors (RECEPTORS, EICOSANOID).
A formylated tripeptide originally isolated from bacterial filtrates that is positively chemotactic to polymorphonuclear leucocytes, and causes them to release lysosomal enzymes and become metabolically activated.
Trihydroxy derivatives of eicosanoic acids. They are primarily derived from arachidonic acid, however eicosapentaenoic acid derivatives also exist. Many of them are naturally occurring mediators of immune regulation.
A phospholipid derivative formed by PLATELETS; BASOPHILS; NEUTROPHILS; MONOCYTES; and MACROPHAGES. It is a potent platelet aggregating agent and inducer of systemic anaphylactic symptoms, including HYPOTENSION; THROMBOCYTOPENIA; NEUTROPENIA; and BRONCHOCONSTRICTION.
Zymosan is a polysaccharide derived from the cell walls of Saccharomyces cerevisiae, commonly used in research as an immunostimulant to induce inflammation and study phagocytosis, complement activation, and oxidative burst in neutrophils and macrophages.
Derivatives of ACETIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the carboxymethane structure.
Drugs that are used to treat asthma.
(5Z)-(15S)-11 alpha-Hydroxy-9,15-dioxoprostanoate:NAD(P)+ delta(13)-oxidoreductase. An enzyme active in prostaglandin E and F catabolism. It catalyzes the reduction of the double bond at the 13-14 position of the 15-ketoprostaglandins and uses NADPH as cofactor. EC 1.3.1.48.
20-carbon saturated monocarboxylic acids.
Granular leukocytes with a nucleus that usually has two lobes connected by a slender thread of chromatin, and cytoplasm containing coarse, round granules that are uniform in size and stainable by eosin.
Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.
A chemically diverse group of substances produced by various tissues in the body that cause slow contraction of smooth muscle; they have other intense but varied pharmacologic activities.
The movement of leukocytes in response to a chemical concentration gradient or to products formed in an immunologic reaction.
A form of bronchial disorder with three distinct components: airway hyper-responsiveness (RESPIRATORY HYPERSENSITIVITY), airway INFLAMMATION, and intermittent AIRWAY OBSTRUCTION. It is characterized by spasmodic contraction of airway smooth muscle, WHEEZING, and dyspnea (DYSPNEA, PAROXYSMAL).
A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.
A potent lipoxygenase inhibitor that interferes with arachidonic acid metabolism. The compound also inhibits formyltetrahydrofolate synthetase, carboxylesterase, and cyclooxygenase to a lesser extent. It also serves as an antioxidant in fats and oils.
EXOPEPTIDASES that specifically act on dipeptides. EC 3.4.13.
Granulated cells that are found in almost all tissues, most abundantly in the skin and the gastrointestinal tract. Like the BASOPHILS, mast cells contain large amounts of HISTAMINE and HEPARIN. Unlike basophils, mast cells normally remain in the tissues and do not circulate in the blood. Mast cells, derived from the bone marrow stem cells, are regulated by the STEM CELL FACTOR.
Tosyl compounds are organic derivatives characterized by the introduction of a tosyl group, which is the sulfonate ester of p-toluenesulfonic acid (CH3C6H4SO3H), into an organic molecule through a substitution reaction.
Granular leukocytes characterized by a relatively pale-staining, lobate nucleus and cytoplasm containing coarse dark-staining granules of variable size and stainable by basic dyes.
The most common and most biologically active of the mammalian prostaglandins. It exhibits most biological activities characteristic of prostaglandins and has been used extensively as an oxytocic agent. The compound also displays a protective effect on the intestinal mucosa.
A transferase that catalyzes the addition of aliphatic, aromatic, or heterocyclic FREE RADICALS as well as EPOXIDES and arene oxides to GLUTATHIONE. Addition takes place at the SULFUR. It also catalyzes the reduction of polyol nitrate by glutathione to polyol and nitrite.
A stable, physiologically active compound formed in vivo from the prostaglandin endoperoxides. It is important in the platelet-release reaction (release of ADP and serotonin).
A subclass of EXOPEPTIDASES that act on the free N terminus end of a polypeptide liberating a single amino acid residue. EC 3.4.11.
The minor fragment formed when C5 convertase cleaves C5 into C5a and COMPLEMENT C5B. C5a is a 74-amino-acid glycopeptide with a carboxy-terminal ARGININE that is crucial for its spasmogenic activity. Of all the complement-derived anaphylatoxins, C5a is the most potent in mediating immediate hypersensitivity (HYPERSENSITIVITY, IMMEDIATE), smooth MUSCLE CONTRACTION; HISTAMINE RELEASE; and migration of LEUKOCYTES to site of INFLAMMATION.
Chromones are a class of chemical compounds that contain a benzopyran-4-one core structure, which are found in various natural and synthetic substances, including some medications used to treat asthma and allergies.
Chemical substances that attract or repel cells. The concept denotes especially those factors released as a result of tissue injury, microbial invasion, or immunologic activity, that attract LEUKOCYTES; MACROPHAGES; or other cells to the site of infection or insult.
A generic grouping for dihydric alcohols with the hydroxy groups (-OH) located on different carbon atoms. They are viscous liquids with high boiling points for their molecular weights.
The rate dynamics in chemical or physical systems.
Narrowing of the caliber of the BRONCHI, physiologically or as a result of pharmacological intervention.
Chemical agents that increase the permeability of biological or artificial lipid membranes to specific ions. Most ionophores are relatively small organic molecules that act as mobile carriers within membranes or coalesce to form ion permeable channels across membranes. Many are antibiotics, and many act as uncoupling agents by short-circuiting the proton gradient across mitochondrial membranes.
The secretion of histamine from mast cell and basophil granules by exocytosis. This can be initiated by a number of factors, all of which involve binding of IgE, cross-linked by antigen, to the mast cell or basophil's Fc receptors. Once released, histamine binds to a number of different target cell receptors and exerts a wide variety of effects.
The relationship between the dose of an administered drug and the response of the organism to the drug.
An amine derived by enzymatic decarboxylation of HISTIDINE. It is a powerful stimulant of gastric secretion, a constrictor of bronchial smooth muscle, a vasodilator, and also a centrally acting neurotransmitter.
A lipoxygenase metabolite of ARACHIDONIC ACID. It is a highly selective ligand used to label mu-opioid receptors in both membranes and tissue sections. The 12-S-HETE analog has been reported to augment tumor cell metastatic potential through activation of protein kinase C. (J Pharmacol Exp Ther 1995; 274(3):1545-51; J Natl Cancer Inst 1994; 86(15):1145-51)
Phospholipases that hydrolyze one of the acyl groups of phosphoglycerides or glycerophosphatidates.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
White blood cells. These include granular leukocytes (BASOPHILS; EOSINOPHILS; and NEUTROPHILS) as well as non-granular leukocytes (LYMPHOCYTES and MONOCYTES).
Phospholipases that hydrolyze the acyl group attached to the 2-position of PHOSPHOGLYCERIDES.
Phenylpropionates are a class of organic compounds, including certain drugs such as ephedrine and pseudoephedrine, which contain a phenylethanoic acid structure with a propionate substitution.
A dual inhibitor of both cyclooxygenase and lipoxygenase pathways. It exerts an anti-inflammatory effect by inhibiting the formation of prostaglandins and leukotrienes. The drug also enhances pulmonary hypoxic vasoconstriction and has a protective effect after myocardial ischemia.
Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.
A derivative of complement C5a, generated when the carboxy-terminal ARGININE is removed by CARBOXYPEPTIDASE B present in normal human serum. C5a des-Arg shows complete loss of spasmogenic activity though it retains some chemotactic ability (CHEMOATTRACTANTS).
The principal cyclooxygenase metabolite of arachidonic acid. It is released upon activation of mast cells and is also synthesized by alveolar macrophages. Among its many biological actions, the most important are its bronchoconstrictor, platelet-activating-factor-inhibitory, and cytotoxic effects.
Important polyunsaturated fatty acid found in fish oils. It serves as the precursor for the prostaglandin-3 and thromboxane-3 families. A diet rich in eicosapentaenoic acid lowers serum lipid concentration, reduces incidence of cardiovascular disorders, prevents platelet aggregation, and inhibits arachidonic acid conversion into the thromboxane-2 and prostaglandin-2 families.
Benzopyrroles with the nitrogen at the number one carbon adjacent to the benzyl portion, in contrast to ISOINDOLES which have the nitrogen away from the six-membered ring.
The larger air passages of the lungs arising from the terminal bifurcation of the TRACHEA. They include the largest two primary bronchi which branch out into secondary bronchi, and tertiary bronchi which extend into BRONCHIOLES and PULMONARY ALVEOLI.
An antineoplastic agent that inhibits DNA synthesis through the inhibition of ribonucleoside diphosphate reductase.
Organic compounds containing the carboxy group (-COOH). This group of compounds includes amino acids and fatty acids. Carboxylic acids can be saturated, unsaturated, or aromatic.
Derivatives of propionic acid. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the carboxyethane structure.
Usually high-molecular-weight, straight-chain primary alcohols, but can also range from as few as 4 carbons, derived from natural fats and oils, including lauryl, stearyl, oleyl, and linoleyl alcohols. They are used in pharmaceuticals, cosmetics, detergents, plastics, and lube oils and in textile manufacture. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
A thiol-containing non-essential amino acid that is oxidized to form CYSTINE.
A non-steroidal anti-inflammatory agent (NSAID) that inhibits the enzyme cyclooxygenase necessary for the formation of prostaglandins and other autacoids. It also inhibits the motility of polymorphonuclear leukocytes.
Determination of the spectra of ultraviolet absorption by specific molecules in gases or liquids, for example Cl2, SO2, NO2, CS2, ozone, mercury vapor, and various unsaturated compounds. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
A sequence-related subfamily of ATP-BINDING CASSETTE TRANSPORTERS that actively transport organic substrates. Although considered organic anion transporters, a subset of proteins in this family have also been shown to convey drug resistance to neutral organic drugs. Their cellular function may have clinical significance for CHEMOTHERAPY in that they transport a variety of ANTINEOPLASTIC AGENTS. Overexpression of proteins in this class by NEOPLASMS is considered a possible mechanism in the development of multidrug resistance (DRUG RESISTANCE, MULTIPLE). Although similar in function to P-GLYCOPROTEINS, the proteins in this class share little sequence homology to the p-glycoprotein family of proteins.
Dicarboxylic acids are organic compounds containing two carboxyl (-COOH) groups in their structure, making them capable of forming salts and esters by losing two hydrogen ions.
A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.
INFLAMMATION of PLEURA, the lining of the LUNG. When PARIETAL PLEURA is involved, there is pleuritic CHEST PAIN.
FATTY ACIDS in which the carbon chain contains one or more double or triple carbon-carbon bonds.
An enzyme that catalyzes the oxidation of arachidonic acid to yield 12-hydroperoxyarachidonate (12-HPETE) which is itself rapidly converted by a peroxidase to 12-hydroxy-5,8,10,14-eicosatetraenoate (12-HETE). The 12-hydroperoxides are preferentially formed in PLATELETS.
A 20-carbon-chain fatty acid, unsaturated at positions 8, 11, and 14. It differs from arachidonic acid, 5,8,11,14-eicosatetraenoic acid, only at position 5.
A unifocal malignant tumor that consists of atypical pathological MAST CELLS without systemic involvement. It causes local destructive growth in organs other than in skin or bone marrow.
Compounds with a core of fused benzo-pyran rings.
The administration of drugs by the respiratory route. It includes insufflation into the respiratory tract.
An evanescent cutaneous reaction occurring when antibody is injected into a local area on the skin and antigen is subsequently injected intravenously along with a dye. The dye makes the rapidly occurring capillary dilatation and increased vascular permeability readily visible by leakage into the reaction site. PCA is a sensitive reaction for detecting very small quantities of antibodies and is also a method for studying the mechanisms of immediate hypersensitivity.
Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.
The cartilaginous and membranous tube descending from the larynx and branching into the right and left main bronchi.
Compounds or agents that combine with cyclooxygenase (PROSTAGLANDIN-ENDOPEROXIDE SYNTHASES) and thereby prevent its substrate-enzyme combination with arachidonic acid and the formation of eicosanoids, prostaglandins, and thromboxanes.
A cytosolic phospholipase A2 group that plays an important role in the release of free ARACHIDONIC ACID, which in turn is metabolized to PROSTAGLANDINS by the CYCLOOXYGENASE pathway and to LEUKOTRIENES by the 5-LIPOXYGENASE pathway.
The property of blood capillary ENDOTHELIUM that allows for the selective exchange of substances between the blood and surrounding tissues and through membranous barriers such as the BLOOD-AIR BARRIER; BLOOD-AQUEOUS BARRIER; BLOOD-BRAIN BARRIER; BLOOD-NERVE BARRIER; BLOOD-RETINAL BARRIER; and BLOOD-TESTIS BARRIER. Small lipid-soluble molecules such as carbon dioxide and oxygen move freely by diffusion. Water and water-soluble molecules cannot pass through the endothelial walls and are dependent on microscopic pores. These pores show narrow areas (TIGHT JUNCTIONS) which may limit large molecule movement.
Drugs that selectively bind to but do not activate histamine H1 receptors, thereby blocking the actions of endogenous histamine. Included here are the classical antihistaminics that antagonize or prevent the action of histamine mainly in immediate hypersensitivity. They act in the bronchi, capillaries, and some other smooth muscles, and are used to prevent or allay motion sickness, seasonal rhinitis, and allergic dermatitis and to induce somnolence. The effects of blocking central nervous system H1 receptors are not as well understood.
Effective in the initiation of protein synthesis. The initiating methionine residue enters the ribosome as N-formylmethionyl tRNA. This process occurs in Escherichia coli and other bacteria as well as in the mitochondria of eucaryotic cells.
C5 plays a central role in both the classical and the alternative pathway of COMPLEMENT ACTIVATION. C5 is cleaved by C5 CONVERTASE into COMPLEMENT C5A and COMPLEMENT C5B. The smaller fragment C5a is an ANAPHYLATOXIN and mediator of inflammatory process. The major fragment C5b binds to the membrane initiating the spontaneous assembly of the late complement components, C5-C9, into the MEMBRANE ATTACK COMPLEX.
Intracellular fluid from the cytoplasm after removal of ORGANELLES and other insoluble cytoplasmic components.
A pathological process characterized by injury or destruction of tissues caused by a variety of cytologic and chemical reactions. It is usually manifested by typical signs of pain, heat, redness, swelling, and loss of function.
Asthmatic adverse reaction (e.g., BRONCHOCONSTRICTION) to conventional NSAIDS including aspirin use.
Leukocytes with abundant granules in the cytoplasm. They are divided into three groups according to the staining properties of the granules: neutrophilic, eosinophilic, and basophilic. Mature granulocytes are the NEUTROPHILS; EOSINOPHILS; and BASOPHILS.
An immunoglobulin associated with MAST CELLS. Overexpression has been associated with allergic hypersensitivity (HYPERSENSITIVITY, IMMEDIATE).
A 20-carbon unsaturated fatty acid containing 4 alkyne bonds. It inhibits the enzymatic conversion of arachidonic acid to prostaglandins E(2) and F(2a).
An enzyme, sometimes called GGT, with a key role in the synthesis and degradation of GLUTATHIONE; (GSH, a tripeptide that protects cells from many toxins). It catalyzes the transfer of the gamma-glutamyl moiety to an acceptor amino acid.
A group of compounds derived from unsaturated 20-carbon fatty acids, primarily arachidonic acid, via the cyclooxygenase pathway. They are extremely potent mediators of a diverse group of physiological processes.
Cytotaxins liberated from normal or invading cells that specifically attract eosinophils; they may be complement fragments, lymphokines, neutrophil products, histamine or other; the best known is the tetrapeptide ECF-A, released mainly by mast cells.
Physiologically, the opposition to flow of air caused by the forces of friction. As a part of pulmonary function testing, it is the ratio of driving pressure to the rate of air flow.
An enzyme that catalyzes the oxidation of arachidonic acid to yield 15-hydroperoxyarachidonate (15-HPETE) which is rapidly converted to 15-hydroxy-5,8,11,13-eicosatetraenoate (15-HETE). The 15-hydroperoxides are preferentially formed in NEUTROPHILS and LYMPHOCYTES.
Exudates are fluids, CELLS, or other cellular substances that are slowly discharged from BLOOD VESSELS usually from inflamed tissues. Transudates are fluids that pass through a membrane or squeeze through tissue or into the EXTRACELLULAR SPACE of TISSUES. Transudates are thin and watery and contain few cells or PROTEINS.
A family of G-protein-coupled receptors that was originally identified by its ability to bind N-formyl peptides such as N-FORMYLMETHIONINE LEUCYL-PHENYLALANINE. Since N-formyl peptides are found in MITOCHONDRIA and BACTERIA, this class of receptors is believed to play a role in mediating cellular responses to cellular damage and bacterial invasion. However, non-formylated peptide ligands have also been found for this receptor class.
The endogenous compounds that mediate inflammation (AUTACOIDS) and related exogenous compounds including the synthetic prostaglandins (PROSTAGLANDINS, SYNTHETIC).
Classic quantitative assay for detection of antigen-antibody reactions using a radioactively labeled substance (radioligand) either directly or indirectly to measure the binding of the unlabeled substance to a specific antibody or other receptor system. Non-immunogenic substances (e.g., haptens) can be measured if coupled to larger carrier proteins (e.g., bovine gamma-globulin or human serum albumin) capable of inducing antibody formation.
A rare acute myeloid leukemia in which the primary differentiation is to BASOPHILS. It is characterized by an extreme increase of immature basophilic granulated cells in the bone marrow and blood. Mature basophils are usually sparse.
Agents that are used to treat allergic reactions. Most of these drugs act by preventing the release of inflammatory mediators or inhibiting the actions of released mediators on their target cells. (From AMA Drug Evaluations Annual, 1994, p475)
Tritium is an isotope of hydrogen (specifically, hydrogen-3) that contains one proton and two neutrons in its nucleus, making it radioactive with a half-life of about 12.3 years, and is used in various applications including nuclear research, illumination, and dating techniques due to its low energy beta decay.
Asthma attacks following a period of exercise. Usually the induced attack is short-lived and regresses spontaneously. The magnitude of postexertional airway obstruction is strongly influenced by the environment in which exercise is performed (i.e. inhalation of cold air during physical exertion markedly augments the severity of the airway obstruction; conversely, warm humid air blunts or abolishes it).
Tests involving inhalation of allergens (nebulized or in dust form), nebulized pharmacologically active solutions (e.g., histamine, methacholine), or control solutions, followed by assessment of respiratory function. These tests are used in the diagnosis of asthma.
Established cell cultures that have the potential to propagate indefinitely.
Cell surface proteins that bind eicosanoids with high affinity and trigger intracellular changes influencing the behavior of cells. Among the eicosanoid receptors are receptors for the prostaglandins, thromboxanes, and leukotrienes.
Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.
The space enclosed by the peritoneum. It is divided into two portions, the greater sac and the lesser sac or omental bursa, which lies behind the STOMACH. The two sacs are connected by the foramen of Winslow, or epiploic foramen.
Cell surface proteins that bind LIPOXINS with high affinity and trigger intracellular changes influencing the behavior of cells.
A subcategory of secreted phospholipases A2 that contains both a negatively charged carboxy-terminal segment and interfacial-binding region specific for PHOSPHATIDYL CHOLINE-containing membranes. This enzyme group may play a role in the release of ARACHIDONIC ACID from phospholipid membranes.
An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.
An acute hypersensitivity reaction due to exposure to a previously encountered ANTIGEN. The reaction may include rapidly progressing URTICARIA, respiratory distress, vascular collapse, systemic SHOCK, and death.
The process in which the neutrophil is stimulated by diverse substances, resulting in degranulation and/or generation of reactive oxygen products, and culminating in the destruction of invading pathogens. The stimulatory substances, including opsonized particles, immune complexes, and chemotactic factors, bind to specific cell-surface receptors on the neutrophil.
A tripeptide with many roles in cells. It conjugates to drugs to make them more soluble for excretion, is a cofactor for some enzymes, is involved in protein disulfide bond rearrangement and reduces peroxides.
Enzyme complexes that catalyze the formation of PROSTAGLANDINS from the appropriate unsaturated FATTY ACIDS, molecular OXYGEN, and a reduced acceptor.
Washing liquid obtained from irrigation of the lung, including the BRONCHI and the PULMONARY ALVEOLI. It is generally used to assess biochemical, inflammatory, or infection status of the lung.
Inorganic or organic salts and esters of boric acid.
Round, granular, mononuclear phagocytes found in the alveoli of the lungs. They ingest small inhaled particles resulting in degradation and presentation of the antigen to immunocompetent cells.
A group of 1,2-benzenediols that contain the general formula R-C6H5O2.
The sudden, forceful, involuntary expulsion of air from the NOSE and MOUTH caused by irritation to the MUCOUS MEMBRANES of the upper RESPIRATORY TRACT.
Elements of limited time intervals, contributing to particular results or situations.
(11 alpha,13E,15S)-11,15-Dihydroxy-9-oxoprost-13-en-1-oic acid (PGE(1)); (5Z,11 alpha,13E,15S)-11,15-dihydroxy-9-oxoprosta-5,13-dien-1-oic acid (PGE(2)); and (5Z,11 alpha,13E,15S,17Z)-11,15-dihydroxy-9-oxoprosta-5,13,17-trien-1-oic acid (PGE(3)). Three of the six naturally occurring prostaglandins. They are considered primary in that no one is derived from another in living organisms. Originally isolated from sheep seminal fluid and vesicles, they are found in many organs and tissues and play a major role in mediating various physiological activities.
Proteins prepared by recombinant DNA technology.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Anti-inflammatory agents that are non-steroidal in nature. In addition to anti-inflammatory actions, they have analgesic, antipyretic, and platelet-inhibitory actions.They act by blocking the synthesis of prostaglandins by inhibiting cyclooxygenase, which converts arachidonic acid to cyclic endoperoxides, precursors of prostaglandins. Inhibition of prostaglandin synthesis accounts for their analgesic, antipyretic, and platelet-inhibitory actions; other mechanisms may contribute to their anti-inflammatory effects.
The forcing into the skin of liquid medication, nutrient, or other fluid through a hollow needle, piercing the top skin layer.
The diffusion or accumulation of neutrophils in tissues or cells in response to a wide variety of substances released at the sites of inflammatory reactions.
Physiologically active compounds found in many organs of the body. They are formed in vivo from the prostaglandin endoperoxides and cause platelet aggregation, contraction of arteries, and other biological effects. Thromboxanes are important mediators of the actions of polyunsaturated fatty acids transformed by cyclooxygenase.
Compounds that bind to and inhibit the action of 5-LIPOXYGENASE-ACTIVATING PROTEINS.
Compounds with two triple bonds. Some of them are CYTOTOXINS.
Artifactual vesicles formed from the endoplasmic reticulum when cells are disrupted. They are isolated by differential centrifugation and are composed of three structural features: rough vesicles, smooth vesicles, and ribosomes. Numerous enzyme activities are associated with the microsomal fraction. (Glick, Glossary of Biochemistry and Molecular Biology, 1990; from Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)
The process of losing secretory granules (SECRETORY VESICLES). This occurs, for example, in mast cells, basophils, neutrophils, eosinophils, and platelets when secretory products are released from the granules by EXOCYTOSIS.
Cell surface molecules on cells of the immune system that specifically bind surface molecules or messenger molecules and trigger changes in the behavior of cells. Although these receptors were first identified in the immune system, many have important functions elsewhere.
The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.
Compounds or agents that combine with an enzyme in such a manner as to prevent the normal substrate-enzyme combination and the catalytic reaction.
Allergic rhinitis that occurs at the same time every year. It is characterized by acute CONJUNCTIVITIS with lacrimation and ITCHING, and regarded as an allergic condition triggered by specific ALLERGENS.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
Measure of the maximum amount of air that can be expelled in a given number of seconds during a FORCED VITAL CAPACITY determination . It is usually given as FEV followed by a subscript indicating the number of seconds over which the measurement is made, although it is sometimes given as a percentage of forced vital capacity.
An intense itching sensation that produces the urge to rub or scratch the skin to obtain relief.
A cyclic endoperoxide intermediate produced by the action of CYCLOOXYGENASE on ARACHIDONIC ACID. It is further converted by a series of specific enzymes to the series 2 prostaglandins.
A vascular reaction of the skin characterized by erythema and wheal formation due to localized increase of vascular permeability. The causative mechanism may be allergy, infection, or stress.
The relatively long-lived phagocytic cell of mammalian tissues that are derived from blood MONOCYTES. Main types are PERITONEAL MACROPHAGES; ALVEOLAR MACROPHAGES; HISTIOCYTES; KUPFFER CELLS of the liver; and OSTEOCLASTS. They may further differentiate within chronic inflammatory lesions to EPITHELIOID CELLS or may fuse to form FOREIGN BODY GIANT CELLS or LANGHANS GIANT CELLS. (from The Dictionary of Cell Biology, Lackie and Dow, 3rd ed.)
A quaternary ammonium parasympathomimetic agent with the muscarinic actions of ACETYLCHOLINE. It is hydrolyzed by ACETYLCHOLINESTERASE at a considerably slower rate than ACETYLCHOLINE and is more resistant to hydrolysis by nonspecific CHOLINESTERASES so that its actions are more prolonged. It is used as a parasympathomimetic bronchoconstrictor agent and as a diagnostic aid for bronchial asthma. (From Martindale, The Extra Pharmacopoeia, 30th ed, p1116)
A form of hypersensitivity affecting the respiratory tract. It includes ASTHMA and RHINITIS, ALLERGIC, SEASONAL.
The phenomenon whereby compounds whose molecules have the same number and kind of atoms and the same atomic arrangement, but differ in their spatial relationships. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
An albumin obtained from the white of eggs. It is a member of the serpin superfamily.
Substances that reduce or suppress INFLAMMATION.
A selective histamine H1-receptor antagonist devoid of central nervous system depressant activity. The drug was used for ALLERGY but withdrawn due to causing LONG QT SYNDROME.
An unstable intermediate between the prostaglandin endoperoxides and thromboxane B2. The compound has a bicyclic oxaneoxetane structure. It is a potent inducer of platelet aggregation and causes vasoconstriction. It is the principal component of rabbit aorta contracting substance (RCS).
Abnormal fluid accumulation in TISSUES or body cavities. Most cases of edema are present under the SKIN in SUBCUTANEOUS TISSUE.
The physiologically active and stable hydrolysis product of EPOPROSTENOL. Found in nearly all mammalian tissue.
A hexosaminidase specific for non-reducing N-acetyl-D-hexosamine residues in N-acetyl-beta-D-hexosaminides. It acts on GLUCOSIDES; GALACTOSIDES; and several OLIGOSACCHARIDES. Two specific mammalian isoenzymes of beta-N-acetylhexoaminidase are referred to as HEXOSAMINIDASE A and HEXOSAMINIDASE B. Deficiency of the type A isoenzyme causes TAY-SACHS DISEASE, while deficiency of both A and B isozymes causes SANDHOFF DISEASE. The enzyme has also been used as a tumor marker to distinguish between malignant and benign disease.
Adrenal cortex hormones are steroid hormones produced by the outer portion of the adrenal gland, consisting of glucocorticoids, mineralocorticoids, and androgens, which play crucial roles in various physiological processes such as metabolism regulation, stress response, electrolyte balance, and sexual development and function.
The number of WHITE BLOOD CELLS per unit volume in venous BLOOD. A differential leukocyte count measures the relative numbers of the different types of white cells.
Benzene rings which contain two ketone moieties in any position. They can be substituted in any position except at the ketone groups.
The movement of cells or organisms toward or away from a substance in response to its concentration gradient.
A cycloheptathiophene blocker of histamine H1 receptors and release of inflammatory mediators. It has been proposed for the treatment of asthma, rhinitis, skin allergies, and anaphylaxis.
Tendency of the smooth muscle of the tracheobronchial tree to contract more intensely in response to a given stimulus than it does in the response seen in normal individuals. This condition is present in virtually all symptomatic patients with asthma. The most prominent manifestation of this smooth muscle contraction is a decrease in airway caliber that can be readily measured in the pulmonary function laboratory.
Highly reactive compounds produced when oxygen is reduced by a single electron. In biological systems, they may be generated during the normal catalytic function of a number of enzymes and during the oxidation of hemoglobin to METHEMOGLOBIN. In living organisms, SUPEROXIDE DISMUTASE protects the cell from the deleterious effects of superoxides.
Inflammation of the mucous membrane of the nose similar to that found in hay fever except that symptoms persist throughout the year. The causes are usually air-borne allergens, particularly dusts, feathers, molds, animal fur, etc.
Drugs that bind to but do not activate histamine receptors, thereby blocking the actions of histamine or histamine agonists. Classical antihistaminics block the histamine H1 receptors only.
Altered reactivity to an antigen, which can result in pathologic reactions upon subsequent exposure to that particular antigen.
Any hindrance to the passage of air into and out of the nose. The obstruction may be unilateral or bilateral, and may involve any part of the NASAL CAVITY.
One of the virulence factors produced by BORDETELLA PERTUSSIS. It is a multimeric protein composed of five subunits S1 - S5. S1 contains mono ADPribose transferase activity.
Large, phagocytic mononuclear leukocytes produced in the vertebrate BONE MARROW and released into the BLOOD; contain a large, oval or somewhat indented nucleus surrounded by voluminous cytoplasm and numerous organelles.
Synthetic compounds that are analogs of the naturally occurring prostaglandin endoperoxides and that mimic their pharmacologic and physiologic activities. They are usually more stable than the naturally occurring compounds.
A member of the CXC chemokine family that plays a role in the regulation of the acute inflammatory response. It is secreted by variety of cell types and induces CHEMOTAXIS of NEUTROPHILS and other inflammatory cells.

Effects of lipid mediator antagonists on predominant mediator-controlled asthmatic reactions in passively sensitized guinea pigs. (1/238)

The role of cysteinyl leukotrienes (cys-LTs) and thromboxane A(2) (TXA(2)) in guinea pig models of aspects of bronchial asthma was investigated. In a novel antigen (BSA)-induced asthmatic model using passively sensitized guinea pigs, pretreatment with varying doses of indomethacin controlled the ratio of followed lipid mediators, LTC(4)/D(4)/E(4) and TXB(2), in lungs of challenged guinea pigs. The predominant mediator in indomethacin-untreated asthma was TXA(2), and complete inhibition of cyclooxygenase by i.v. injection of 5-mg/kg indomethacin-induced cys-LTs mainly mediated asthmatic response. Furthermore, a 1-mg/kg indomethacin dose induced an asthmatic state where both cys-LTs and TXA(2) equally participated. Either LTD(4) or TXA(2) receptor antagonists given alone inhibited the asthmatic response in conditions where the corresponding mediator plays a predominant role. The combination of LTD(4) and TXA(2) receptor antagonists exhibited significant effects irrespective of the condition used. Under conditions where both mediators equally participate, a combination of both receptor antagonists showed additive inhibition. YM158, a newly synthesized and orally active dual antagonist for LTD(4) and TXA(2) receptors, showed the same antiasthmatic effect as a combinated LTD(4) receptor antagonist and a TXA(2) receptor antagonist mixture. Therefore, broad-acting compounds such as YM158 are expected to have antiasthmatic efficacies in a broader class of asthmatic patients than single-acting drugs.  (+info)

Identification, molecular cloning, expression, and characterization of a cysteinyl leukotriene receptor. (2/238)

The cysteinyl leukotrienes (CysLTs) have been implicated in the pathophysiology of inflammatory disorders, in particular asthma, for which the CysLT receptor antagonists pranlukast, zafirlukast, and montelukast, have been introduced recently as novel therapeutics. Here we report on the molecular cloning, expression, localization, and pharmacological characterization of a CysLT receptor (CysLTR), which was identified by ligand fishing of orphan seven-transmembrane-spanning, G protein-coupled receptors. This receptor, expressed in human embryonic kidney (HEK)-293 cells responded selectively to the individual CysLTs, LTC(4), LTD(4), or LTE(4), with a calcium mobilization response; the rank order potency was LTD(4) (EC(50) = 2.5 nM) > LTC(4) (EC(50) = 24 nM) > LTE(4) (EC(50) = 240 nM). Evidence was provided that LTE(4) is a partial agonist at this receptor. [(3)H]LTD(4) binding and LTD(4)-induced calcium mobilization in HEK-293 cells expressing the CysLT receptor were potently inhibited by the structurally distinct CysLTR antagonists pranlukast, montelukast, zafirlukast, and pobilukast; the rank order potency was pranlukast = zafirlukast > montelukast > pobilukast. LTD(4)-induced calcium mobilization in HEK-293 cells expressing the CysLT receptor was not affected by pertussis toxin, and the signal appears to be the result of the release from intracellular stores. Localization studies indicate the expression of this receptor in several tissues, including human lung, human bronchus, and human peripheral blood leukocytes. The discovery of this receptor, which has characteristics of the purported CysLT(1) receptor subtype, should assist in the elucidation of the pathophysiological roles of the CysLTs and in the identification of additional receptor subtypes.  (+info)

A kinetic binding study to evaluate the pharmacological profile of a specific leukotriene C(4) binding site not coupled to contraction in human lung parenchyma. (3/238)

We report the identification of a novel pharmacological profile for the leukotriene (LT)C(4) binding site we previously identified in human lung parenchyma (HLP). We used a series of classic cysteinyl-LT (CysLT)(1) receptor antagonists belonging to different chemical classes and the dual CysLT(1)-CysLT(2) antagonist BAY u9773 for both binding and functional studies. Because the presence of (S)-decyl-glutathione interfered with cysteinyl-LT binding, with a kinetic protocol we avoided the use of this compound. By means of heterologous dissociation time courses, we demonstrated that zafirlukast, iralukast, and BAY u9773 selectively competed only for (3)H-LTD(4) binding sites, whereas pobilukast, pranlukast, and CGP 57698 dissociated both (3)H-LTC(4) and (3)H-LTD(4) from their binding sites. Thus, with binding studies, we have been able to identify a pharmacological profile for LTC(4) distinct from that of LTD(4) receptor (CysLT(1)) in HLP. On the contrary, in functional studies, all of the classic antagonists tested were able to revert both LTC(4)- and LTD(4)-induced contractions of isolated HLP strips. Thus, LTD(4) and LTC(4) contract isolated HLP strips through the same CysLT(1) receptor. The results of kinetic binding studies, coupled to a sophisticated data analysis, confirm our hypothesis that HLP membranes contain two cysteinyl-LT high-affinity binding sites with different pharmacological profiles. In functional studies, however, LTD(4)- and LTC(4)-induced contractions are mediated by the same CysLT(1) receptor. In conclusion, the specific LTC(4) high-affinity binding site cannot be classified as one of the officially recognized CysLT receptors, and it is not implicated in LTC(4)-induced HLP strip contractions.  (+info)

Characterization of the human cysteinyl leukotriene 2 receptor. (4/238)

The contractile and inflammatory actions of the cysteinyl leukotrienes (CysLTs), LTC(4), LTD(4), and LTE(4), are thought to be mediated through at least two distinct but related CysLT G protein-coupled receptors. The human CysLT(1) receptor has been recently cloned and characterized. We describe here the cloning and characterization of the second cysteinyl leukotriene receptor, CysLT(2), a 346-amino acid protein with 38% amino acid identity to the CysLT(1) receptor. The recombinant human CysLT(2) receptor was expressed in Xenopus oocytes and HEK293T cells and shown to couple to elevation of intracellular calcium when activated by LTC(4), LTD(4), or LTE(4). Analyses of radiolabeled LTD(4) binding to the recombinant CysLT(2) receptor demonstrated high affinity binding and a rank order of potency for competition of LTC(4) = LTD(4) LTE(4). In contrast to the dual CysLT(1)/CysLT(2) antagonist, BAY u9773, the CysLT(1) receptor-selective antagonists MK-571, montelukast (Singulair(TM)), zafirlukast (Accolate(TM)), and pranlukast (Onon(TM)) exhibited low potency in competition for LTD(4) binding and as antagonists of CysLT(2) receptor signaling. CysLT(2) receptor mRNA was detected in lung macrophages and airway smooth muscle, cardiac Purkinje cells, adrenal medulla cells, peripheral blood leukocytes, and brain, and the receptor gene was mapped to chromosome 13q14, a region linked to atopic asthma.  (+info)

Lipoxin A4 antagonizes the mitogenic effects of leukotriene D4 in human renal mesangial cells. Differential activation of MAP kinases through distinct receptors. (5/238)

The lipoxygenase-derived eicosanoids leukotrienes and lipoxins are well defined regulators of hemeodynamics and leukocyte recruitment in inflammatory conditions. Here, we describe a novel bioaction of lipoxin A(4) (LXA(4)), namely inhibition of leukotriene D(4) (LTD(4))-induced human renal mesangial cell proliferation, and investigate the signal transduction mechanisms involved. LXA(4) blocked LTD(4)-stimulated phosphatidylinositol 3-kinase (PI 3-kinase) activity in parallel to inhibition of LTD(4)-induced mesangial cell proliferation. Screening of a human mesangial cell cDNA library revealed expression of the recently described cys-leukotriene(1)/LTD(4) receptor. LTD(4)-induced mesangial cell proliferation required both extracellular-related signal regulated kinase (erk) and PI 3-kinase activation and may involve platelet-derived growth factor receptor transactivation. LTD(4)-stimulated the MAP kinases erk and p38 via a pertussis toxin (PTX)-sensitive pathway dependent on PI 3-kinase and protein kinase C activation. On screening a cDNA library, mesangial cells were found to express the previously described LXA(4) receptor. In contrast to LTD(4), LXA(4) showed differential activation of erk and p38. LXA(4) activation of erk was insensitive to PTX and PI 3-kinase inhibition, whereas LXA(4) activation of p38 was sensitive to PTX and could be blocked by the LTD(4) receptor antagonist SKF 104353. These data suggest that LXA(4) stimulation of the MAP kinase superfamily involves two distinct receptors: one shared with LTD(4) and coupled to a PTX-sensitive G protein (G(i)) and a second coupled via an alternative G protein, such as G(q) or G(12), to erk activation. These data expand on the spectrum of LXA(4) bioactions within an inflammatory milieu.  (+info)

Effect of YM158, a dual lipid mediator antagonist, on immediate and late asthmatic responses, and on airway hyper-responsiveness in guinea pigs. (6/238)

The effects of lipid mediator antagonists: the LTD4-receptor antagonist pranlukast, the TXA2-receptor antagonist seratrodast, and the novel dual LTD4- and TXA2-receptor antagonist YM158 (3-[(4-tert-butylthiazol-2-yl)methoxy]-5'-[3-(4-chlorobenzenesu lfonyl) propyl]-2'-(1H-tetrazol-5-ylmethoxy)benzanilide monosodium salt monohydrate) were investigated in animals exhibiting immediate asthmatic response (IAR), late asthmatic response (LAR) and airway hyper-responsiveness (AHR). Antigen-induced LAR and AfR are inhibited by orally administered pranlukast (30, 100 mg/kg) and seratrodast (3, 10 mg/kg). YM158 (30 mg/kg), orally administered before or after IAR induction, also inhibited both LAR and AHR. However, while the inhibitory effects of pranlukast and seratrodast on IAR were marginal, the effects of YM158 (3, 10, 30 mg/kg) were dose-dependent, probably due to its multiple sites of action. Additionally, orally administered YM158 (30 mg/kg) inhibited ozone-induced AHR in guinea pigs. Thus, an antagonist that inhibits several lipid mediators might exhibit greater efficacy in treating asthmatic responses than antagonists with a single site of action. Therefore, YM158 shows great promise as a drug that will be able to treat bronchial asthma and related disorders more potently than currently used single-pathway inhibitors.  (+info)

IL-5 up-regulates cysteinyl leukotriene 1 receptor expression in HL-60 cells differentiated into eosinophils. (7/238)

The cysteinyl leukotrienes, leukotriene (LT) C(4), LTD(4), and LTE(4), are lipid mediators that have been implicated in the pathogenesis of several inflammatory processes, including asthma. The human LTD(4) receptor, CysLT(1)R, was recently cloned and characterized. We had previously shown that HL-60 cells differentiated toward the eosinophilic lineage (HL-60/eos) developed specific functional LTD(4) receptors. The present work was undertaken to study the potential modulation of CysLT(1)R expression in HL-60/eos by IL-5, an important regulator of eosinophil function. Here, we report that IL-5 rapidly up-regulates CysLT(1)R mRNA expression, with consequently enhanced CysLT(1)R protein expression and function in HL-60/eos. CysLT(1)R mRNA expression was augmented 2- to 15-fold following treatment with IL-5 (1-20 ng/ml). The effect was seen after 2 h, was maximal by 4 h, and maintained at 8 h. Although CysLT(1)R mRNA was constitutively expressed in undifferentiated HL-60 cells, its expression was not modulated by IL-5 in the absence of differentiation. Differentiated HL-60/eos cells pretreated with IL-5 (10 ng/ml) for 24 h showed enhanced CysLT(1)R expression on the cell surface, as assessed by flow cytometry using a polyclonal anti-CysLT(1)R Ab. They also showed enhanced responsiveness to LTD(4), but not to LTB(4) or platelet-activating factor, in terms of Ca(2+) mobilization, and augmented the chemotactic response to LTD(4). Our findings suggest a possible mechanism by which IL-5 can modulate eosinophil functions and particularly their responsiveness to LTD(4), and thus contribute to the pathogenesis of asthma and allergic diseases.  (+info)

Molecular cloning and characterization of a second human cysteinyl leukotriene receptor: discovery of a subtype selective agonist. (8/238)

The cysteinyl leukotrienes (CysLTs) are potent biological mediators in the pathophysiology of inflammatory diseases, in particular of airway obstruction in asthma. Pharmacological studies have suggested the existence of at least two types of CysLT receptors, designated CysLT(1) and CysLT(2). The CysLT(1) receptor has been cloned recently. Here we report the molecular cloning, expression, localization, and functional characterization of a human G protein-coupled receptor that has the expected characteristics of a CysLT(2) receptor. This new receptor is selectively activated by nanomolar concentrations of CysLTs with a rank order potency of LTC(4) = LTD(4) >> LTE(4). The leukotriene analog BAY u9773, reported to be a dual CysLT(1)/CysLT(2) antagonist, was found to be an antagonist at CysLT(1) sites but acted as a partial agonist at this new receptor. The structurally different CysLT(1) receptor-selective antagonists zafirlukast, montelukast, and MK-571 did not inhibit the agonist-mediated calcium mobilization of CysLT(2) receptors at physiological concentrations. Localization studies indicate highest expression of CysLT(2) receptors in adrenal glands, heart, and placenta; moderate levels in spleen, peripheral blood leukocytes, and lymph nodes; and low levels in the central nervous system and pituitary. The human CysLT(2) receptor gene is located on chromosome 13q14.12-21.1. The new receptor exhibits all characteristics of the thus far poorly defined CysLT(2) receptor. Moreover, we have identified BAY u9773 as a CysLT(2) selective agonist, which could prove to be of immediate use in understanding the functional roles of the CysLT(2) receptor.  (+info)

Leukotriene B4 (LTB4) is a type of lipid mediator called eicosanoid, which is derived from arachidonic acid through the 5-lipoxygenase pathway. It is primarily produced by neutrophils, eosinophils, monocytes, and macrophages in response to various stimuli such as infection, inflammation, or injury. LTB4 acts as a potent chemoattractant and activator of these immune cells, playing a crucial role in the recruitment and activation of neutrophils during acute inflammatory responses. It also enhances the adhesion of leukocytes to endothelial cells, contributing to the development of tissue damage and edema. Dysregulation of LTB4 production has been implicated in several pathological conditions, including asthma, atherosclerosis, and cancer.

Leukotriene A4 (LTA4) is a lipid mediator derived from arachidonic acid, which is released from membrane phospholipids by the action of phospholipase A2. LTA4 is synthesized in the cell through the 5-lipoxygenase pathway and serves as an intermediate in the production of other leukotrienes (LB4, LTC4, LTD4, LTE4) that are involved in inflammation, bronchoconstriction, increased vascular permeability, and recruitment of leukocytes.

Leukotriene A4 is an unstable compound with a short half-life, which can be converted to Leukotriene B4 (LTB4) by the enzyme LTA4 hydrolase or to Leukotriene C4 (LTC4) by the addition of glutathione through the action of LTC4 synthase. These leukotrienes play a significant role in the pathophysiology of asthma, allergies, and other inflammatory diseases.

Leukotriene B4 (LTB4) receptors are a type of G protein-coupled receptor that bind to and are activated by the lipid mediator Leukotriene B4. There are two main types of LTB4 receptors, named BLT1 and BLT2.

BLT1 is highly expressed in cells of the immune system such as neutrophils, eosinophils, monocytes, and dendritic cells, and it mediates many of the pro-inflammatory effects of LTB4, including chemotaxis, adhesion, and activation of these cells.

BLT2 is more widely expressed in various tissues, including the skin, lung, and intestine, and it has been shown to play a role in a variety of physiological and pathological processes, such as pain sensation, wound healing, and cancer progression.

Overall, LTB4 receptors are important targets for the development of therapies aimed at modulating inflammation and immune responses.

Leukotriene receptors are a type of cell surface receptor that bind to and are activated by leukotrienes, which are lipid mediators derived from arachidonic acid. These receptors play an important role in the inflammatory response and are involved in various physiological and pathophysiological processes, including bronchoconstriction, increased vascular permeability, and recruitment of inflammatory cells.

There are two main types of leukotriene receptors: CysLT1 and CysLT2. The CysLT1 receptor has a high affinity for the cysteinyl leukotrienes LTC4, LTD4, and LTE4, while the CysLT2 receptor has a lower affinity for these ligands. Activation of the CysLT1 receptor leads to smooth muscle contraction, increased vascular permeability, and recruitment of inflammatory cells, while activation of the CysLT2 receptor is associated with vasoconstriction and bronchodilation.

Leukotriene receptors are found on various cell types, including immune cells (e.g., eosinophils, mast cells), airway smooth muscle cells, endothelial cells, and epithelial cells. They play a key role in the pathogenesis of asthma and other allergic diseases, as well as in the development of inflammation in response to infection or tissue injury.

Drugs that target leukotriene receptors, such as montelukast (a CysLT1 receptor antagonist), are used in the treatment of asthma and allergic rhinitis. These drugs work by blocking the activation of leukotriene receptors, thereby reducing inflammation and bronchoconstriction.

Leukotriene C4 (LTC4) is a type of lipid mediator called a cysteinyl leukotriene, which is derived from arachidonic acid through the 5-lipoxygenase pathway. It is primarily produced by activated mast cells and basophils, and to a lesser extent by eosinophils, during an allergic response or inflammation.

LTC4 plays a crucial role in the pathogenesis of asthma and other allergic diseases by causing bronchoconstriction, increased vascular permeability, mucus secretion, and recruitment of inflammatory cells to the site of inflammation. It exerts its effects by binding to cysteinyl leukotriene receptors (CysLT1 and CysLT2) found on various cell types, including airway smooth muscle cells, bronchial epithelial cells, and immune cells.

LTC4 is rapidly metabolized to Leukotriene D4 (LTD4) and then to Leukotriene E4 (LTE4) by enzymes such as gamma-glutamyl transpeptidase and dipeptidases, which are present in the extracellular space. These metabolites also have biological activity and contribute to the inflammatory response.

Inhibitors of 5-lipoxygenase or leukotriene receptor antagonists are used as therapeutic agents for the treatment of asthma, allergies, and other inflammatory conditions.

Leukotriene antagonists are a class of medications that work by blocking the action of leukotrienes, which are chemicals released by the immune system in response to an allergen or irritant. Leukotrienes cause airway muscles to tighten and inflammation in the airways, leading to symptoms such as wheezing, shortness of breath, and coughing. By blocking the action of leukotrienes, leukotriene antagonists can help relieve these symptoms and improve lung function. These medications are often used to treat asthma and allergic rhinitis (hay fever). Examples of leukotriene antagonists include montelukast, zafirlukast, and pranlukast.

Leukotriene E4 (LTE4) is a biological mediator derived from the arachidonic acid pathway, which plays a significant role in the inflammatory response. It is a type of leukotriene that is synthesized from leukotriene C4 (LTC4) and leukotriene D4 (LTD4) via the action of enzymes such as gamma-glutamyl transpeptidase and dipeptidases.

LTE4 is a potent bronchoconstrictor, meaning it can cause narrowing of the airways in the lungs, and it also has chemotactic properties that attract inflammatory cells such as eosinophils to sites of inflammation. It is involved in the pathogenesis of asthma and other allergic diseases, where it contributes to bronchoconstriction, increased vascular permeability, and mucus production.

LTE4 can be measured in urine as a biomarker of airway inflammation, particularly in patients with asthma. Increased levels of LTE4 in the urine have been associated with more severe asthma symptoms, poorer lung function, and increased risk of exacerbations.

Leukotriene D4 (LTD4) is a biological mediator derived from arachidonic acid, which is released from membrane phospholipids by the action of phospholipase A2. It is one of the cysteinyl leukotrienes (cys-LTs), along with LTC4 and LTE4, that are produced in the body through the 5-lipoxygenase pathway.

LTD4 plays a significant role in the inflammatory response, particularly in the airways. It is a potent constrictor of bronchial smooth muscle, increases vascular permeability, and recruits eosinophils and other inflammatory cells to the site of inflammation. These actions contribute to the pathogenesis of asthma and allergic rhinitis.

LTD4 exerts its effects by binding to cys-LT receptors (CysLT1 and CysLT2) found on various cell types, including smooth muscle cells, endothelial cells, and inflammatory cells. The activation of these receptors leads to a cascade of intracellular signaling events that result in the observed biological responses.

Inhibitors of 5-lipoxygenase or cys-LT receptor antagonists are used as therapeutic agents for the treatment of asthma and allergic rhinitis, targeting the actions of LTD4 and other cys-LTs to reduce inflammation and bronchoconstriction.

"SRS-A" is an older abbreviation for "Slow-Reacting Substance of Anaphylaxis," which refers to a group of molecules called "leukotrienes." Leukotrienes are mediators of inflammation and play a key role in the pathogenesis of asthma and other allergic diseases. They are produced by mast cells and basophils upon activation, and cause bronchoconstriction, increased vascular permeability, and mucus production.

The term "SRS-A" is not commonly used in modern medical literature, as it has been largely replaced by the more specific names of its individual components: LTC4, LTD4, and LTE4. These leukotrienes are now collectively referred to as the "cysteinyl leukotrienes."

Leukotrienes are a type of lipid mediator derived from arachidonic acid, which is a fatty acid found in the cell membranes of various cells in the body. They are produced by the 5-lipoxygenase (5-LO) pathway and play an essential role in the inflammatory response. Leukotrienes are involved in several physiological and pathophysiological processes, including bronchoconstriction, increased vascular permeability, and recruitment of immune cells to sites of injury or infection.

There are four main types of leukotrienes: LTB4, LTC4, LTD4, and LTE4. These molecules differ from each other based on the presence or absence of specific chemical groups attached to their core structure. Leukotrienes exert their effects by binding to specific G protein-coupled receptors (GPCRs) found on the surface of various cells.

LTB4 is primarily involved in neutrophil chemotaxis and activation, while LTC4, LTD4, and LTE4 are collectively known as cysteinyl leukotrienes (CysLTs). CysLTs cause bronchoconstriction, increased mucus production, and vascular permeability in the airways, contributing to the pathogenesis of asthma and other respiratory diseases.

In summary, leukotrienes are potent lipid mediators that play a crucial role in inflammation and immune responses. Their dysregulation has been implicated in several disease states, making them an important target for therapeutic intervention.

Arachidonate 5-Lipoxygenase (also known as ALOX5 or 5-LO) is a type of enzyme involved in the biosynthesis of leukotrienes, which are important inflammatory mediators. It catalyzes the conversion of arachidonic acid, a polyunsaturated fatty acid, to 5-hydroperoxyeicosatetraenoic acid (5-HPETE), which is then converted to leukotriene A4 (LTA4). LTA4 is a precursor for the synthesis of other leukotrienes, such as LTB4, LTC4, LTD4, and LTE4. These lipid mediators play key roles in various physiological and pathophysiological processes, including inflammation, immune response, and allergic reactions.

The gene encoding arachidonate 5-lipoxygenase is located on human chromosome 10 (10q11.2). Mutations in this gene have been associated with several diseases, such as severe congenital neutropenia, recurrent infections, and increased risk of developing asthma and other allergic disorders. Inhibitors of arachidonate 5-lipoxygenase are used as therapeutic agents for the treatment of inflammatory conditions, including asthma and rheumatoid arthritis.

Epoxide hydrolases are a group of enzymes that catalyze the hydrolysis of epoxides, which are molecules containing a three-membered ring consisting of two carbon atoms and one oxygen atom. This reaction results in the formation of diols, which are molecules containing two hydroxyl groups (-OH).

Epoxide hydrolases play an important role in the detoxification of xenobiotics (foreign substances) and the metabolism of endogenous compounds. They help to convert toxic epoxides into less harmful products, which can then be excreted from the body.

There are two main types of epoxide hydrolases: microsomal epoxide hydrolase (mEH) and soluble epoxide hydrolase (sEH). mEH is primarily responsible for metabolizing xenobiotics, while sEH plays a role in the metabolism of endogenous compounds such as arachidonic acid.

Impaired function or inhibition of epoxide hydrolases has been linked to various diseases, including cancer, cardiovascular disease, and neurological disorders. Therefore, these enzymes are considered important targets for the development of drugs and therapies aimed at treating these conditions.

Lipoxygenase inhibitors are a class of compounds that block the activity of lipoxygenase enzymes. These enzymes are involved in the metabolism of arachidonic acid and other polyunsaturated fatty acids, leading to the production of leukotrienes and other inflammatory mediators. By inhibiting lipoxygenase, these compounds can help reduce inflammation and may have potential therapeutic applications in the treatment of various diseases, including asthma, atherosclerosis, and cancer. Some examples of lipoxygenase inhibitors include nordihydroguaiaretic acid (NDGA), zileuton, and baicalein.

5-Lipoxygenase-activating proteins (FLAPs) are a type of enzyme found in the cell membrane that play a crucial role in the biosynthesis of leukotrienes, which are lipid mediators involved in inflammation and immune responses. FLAPs activate 5-lipoxygenase, an enzyme that catalyzes the conversion of arachidonic acid to leukotriene A4, a precursor for other leukotrienes.

FLAP inhibitors are a class of drugs that block the activity of FLAPs and have been investigated as potential treatments for inflammatory diseases such as asthma, rheumatoid arthritis, and atherosclerosis. By inhibiting FLAP, these drugs can reduce the production of leukotrienes and other pro-inflammatory mediators, thereby alleviating the symptoms of inflammation and potentially slowing down the progression of related diseases.

Hydroxyeicosatetraenoic acids (HETEs) are a type of metabolite produced by the oxidation of arachidonic acid, a polyunsaturated fatty acid that is found in the membranes of cells in the human body. This oxidation process is catalyzed by enzymes called lipoxygenases (LOXs) and cytochrome P450 monooxygenases (CYP450).

HETEs are biologically active compounds that play a role in various physiological and pathophysiological processes, including inflammation, immune response, and cancer. They can act as signaling molecules, modulating the activity of various cell types, such as leukocytes, endothelial cells, and smooth muscle cells.

There are several different types of HETEs, depending on the position of the hydroxyl group (-OH) attached to the arachidonic acid molecule. For example, 5-HETE, 12-HETE, and 15-HETE are produced by 5-LOX, 12-LOX, and 15-LOX, respectively, while CYP450 can produce 20-HETE.

It's worth noting that HETEs have been implicated in various diseases, such as atherosclerosis, hypertension, and cancer, making them potential targets for therapeutic intervention. However, further research is needed to fully understand their roles and develop effective treatments.

Neutrophils are a type of white blood cell that are part of the immune system's response to infection. They are produced in the bone marrow and released into the bloodstream where they circulate and are able to move quickly to sites of infection or inflammation in the body. Neutrophils are capable of engulfing and destroying bacteria, viruses, and other foreign substances through a process called phagocytosis. They are also involved in the release of inflammatory mediators, which can contribute to tissue damage in some cases. Neutrophils are characterized by the presence of granules in their cytoplasm, which contain enzymes and other proteins that help them carry out their immune functions.

Arachidonic acids are a type of polyunsaturated fatty acid that is primarily found in the phospholipids of cell membranes. They contain 20 carbon atoms and four double bonds (20:4n-6), with the first double bond located at the sixth carbon atom from the methyl end.

Arachidonic acids are derived from linoleic acid, an essential fatty acid that cannot be synthesized by the human body and must be obtained through dietary sources such as meat, fish, and eggs. Once ingested, linoleic acid is converted to arachidonic acid in a series of enzymatic reactions.

Arachidonic acids play an important role in various physiological processes, including inflammation, immune response, and cell signaling. They serve as precursors for the synthesis of eicosanoids, which are signaling molecules that include prostaglandins, thromboxanes, and leukotrienes. These eicosanoids have diverse biological activities, such as modulating blood flow, platelet aggregation, and pain perception, among others.

However, excessive production of arachidonic acid-derived eicosanoids has been implicated in various pathological conditions, including inflammation, atherosclerosis, and cancer. Therefore, the regulation of arachidonic acid metabolism is an important area of research for the development of new therapeutic strategies.

Arachidonate lipoxygenases (ALOXs or ALOXE's) are a group of enzymes that catalyze the dioxygenation of polyunsaturated fatty acids, such as arachidonic acid, to form hydroperoxides. These enzymes play a crucial role in the biosynthesis of various eicosanoids, which are signaling molecules involved in inflammation, immunity, and other physiological processes.

There are several isoforms of ALOXs, including 5-lipoxygenase (5-LOX), 12-lipoxygenase (12-LOX), and 15-lipoxygenase (15-LOX), which differ in their substrate specificity and the position of the hydroperoxide group they introduce into the fatty acid. These enzymes are widely distributed in various tissues, including the lungs, liver, and brain, and have been implicated in a variety of diseases, such as cancer, cardiovascular disease, and neurodegenerative disorders.

Inhibition of ALOXs has been explored as a potential therapeutic strategy for the treatment of these diseases, although the development of selective and safe inhibitors has proven to be challenging.

Quinolines are a class of organic compounds that consist of a bicyclic structure made up of a benzene ring fused to a piperidine ring. They have a wide range of applications, but they are perhaps best known for their use in the synthesis of various medications, including antibiotics and antimalarial drugs.

Quinolone antibiotics, such as ciprofloxacin and levofloxacin, work by inhibiting the bacterial enzymes involved in DNA replication and repair. They are commonly used to treat a variety of bacterial infections, including urinary tract infections, pneumonia, and skin infections.

Quinoline-based antimalarial drugs, such as chloroquine and hydroxychloroquine, work by inhibiting the parasite's ability to digest hemoglobin in the red blood cells. They are commonly used to prevent and treat malaria.

It is important to note that quinolines have been associated with serious side effects, including tendinitis and tendon rupture, nerve damage, and abnormal heart rhythms. As with any medication, it is important to use quinolines only under the supervision of a healthcare provider, and to follow their instructions carefully.

Calcimycin is a ionophore compound that is produced by the bacterium Streptomyces chartreusensis. It is also known as Calcineurin A inhibitor because it can bind to and inhibit the activity of calcineurin, a protein phosphatase. In medical research, calcimycin is often used to study calcium signaling in cells.
It has been also used in laboratory studies for its antiproliferative and pro-apoptotic effects on certain types of cancer cells. However, it is not approved for use as a drug in humans.

Arachidonic acid is a type of polyunsaturated fatty acid that is found naturally in the body and in certain foods. It is an essential fatty acid, meaning that it cannot be produced by the human body and must be obtained through the diet. Arachidonic acid is a key component of cell membranes and plays a role in various physiological processes, including inflammation and blood clotting.

In the body, arachidonic acid is released from cell membranes in response to various stimuli, such as injury or infection. Once released, it can be converted into a variety of bioactive compounds, including prostaglandins, thromboxanes, and leukotrienes, which mediate various physiological responses, including inflammation, pain, fever, and blood clotting.

Arachidonic acid is found in high concentrations in animal products such as meat, poultry, fish, and eggs, as well as in some plant sources such as certain nuts and seeds. It is also available as a dietary supplement. However, it is important to note that excessive intake of arachidonic acid can contribute to the development of inflammation and other health problems, so it is recommended to consume this fatty acid in moderation as part of a balanced diet.

Lipoxygenase is an enzyme that catalyzes the dioxygenation of polyunsaturated fatty acids containing a cis,cis-1,4-pentadiene structure, forming hydroperoxides. This reaction is important in the biosynthesis of leukotrienes and lipoxins, which are involved in various inflammatory responses and immune functions. There are several isoforms of lipoxygenase found in different tissues and organisms, including arachidonate 5-lipoxygenase, arachidonate 12-lipoxygenase, and arachidonate 15-lipoxygenase.

Eicosanoids are a group of signaling molecules made by the enzymatic or non-enzymatic oxidation of arachidonic acid and other polyunsaturated fatty acids with 20 carbon atoms. They include prostaglandins, thromboxanes, leukotrienes, and lipoxins, which are involved in a wide range of physiological and pathophysiological processes, such as inflammation, immune response, blood clotting, and smooth muscle contraction. Eicosanoids act as local hormones or autacoids, affecting the function of cells near where they are produced. They are synthesized by various cell types, including immune cells, endothelial cells, and neurons, in response to different stimuli, such as injury, infection, or stress. The balance between different eicosanoids can have significant effects on health and disease.

N-Formylmethionine Leucyl-Phenylalanine (fMLP) is not a medical condition, but rather a synthetic peptide that is often used in laboratory settings for research purposes. It is a formylated methionine residue linked to a leucine and phenylalanine tripeptide.

fMLP is a potent chemoattractant for certain types of white blood cells, including neutrophils and monocytes. When these cells encounter fMLP, they are stimulated to migrate towards the source of the peptide and release various inflammatory mediators. As such, fMLP is often used in studies of inflammation, immune cell function, and signal transduction pathways.

It's important to note that while fMLP has important research applications, it is not a substance that would be encountered or used in clinical medicine.

Lipoxins are a group of naturally occurring, short-lived signaling molecules called eicosanoids that are derived from arachidonic acid, a type of omega-6 fatty acid. They were first discovered in the 1980s and are produced by cells involved in the inflammatory response, such as white blood cells (leukocytes).

Lipoxins have potent anti-inflammatory effects and play a crucial role in regulating and resolving the inflammatory response. They work by modulating the activity of various immune cells, including neutrophils, monocytes, and lymphocytes, and promoting the resolution of inflammation through the activation of anti-inflammatory pathways.

Lipoxins have been shown to have potential therapeutic applications in a variety of inflammatory diseases, such as asthma, arthritis, and inflammatory bowel disease. However, further research is needed to fully understand their mechanisms of action and therapeutic potential.

Platelet-activating factor (PAF) is a potent phospholipid mediator that plays a significant role in various inflammatory and immune responses. It is a powerful lipid signaling molecule released mainly by activated platelets, neutrophils, monocytes, endothelial cells, and other cell types during inflammation or injury.

PAF has a molecular structure consisting of an alkyl chain linked to a glycerol moiety, a phosphate group, and an sn-2 acetyl group. This unique structure allows PAF to bind to its specific G protein-coupled receptor (PAF-R) on the surface of target cells, triggering various intracellular signaling cascades that result in cell activation, degranulation, and aggregation.

The primary functions of PAF include:

1. Platelet activation and aggregation: PAF stimulates platelets to aggregate, release their granules, and activate the coagulation cascade, which can lead to thrombus formation.
2. Neutrophil and monocyte activation: PAF activates these immune cells, leading to increased adhesion, degranulation, and production of reactive oxygen species (ROS) and pro-inflammatory cytokines.
3. Vasodilation and increased vascular permeability: PAF can cause vasodilation by acting on endothelial cells, leading to an increase in blood flow and facilitating the extravasation of immune cells into inflamed tissues.
4. Bronchoconstriction: In the respiratory system, PAF can induce bronchoconstriction and recruitment of inflammatory cells, contributing to asthma symptoms.
5. Neurotransmission modulation: PAF has been implicated in neuroinflammation and may play a role in neuronal excitability, synaptic plasticity, and cognitive functions.

Dysregulated PAF signaling has been associated with several pathological conditions, including atherosclerosis, sepsis, acute respiratory distress syndrome (ARDS), ischemia-reperfusion injury, and neuroinflammatory disorders. Therefore, targeting the PAF pathway may provide therapeutic benefits in these diseases.

Zymosan is a type of substance that is derived from the cell walls of yeast and some types of fungi. It's often used in laboratory research as an agent to stimulate inflammation, because it can activate certain immune cells (such as neutrophils) and cause them to release pro-inflammatory chemicals.

In medical terms, Zymosan is sometimes used as a tool for studying the immune system and inflammation in experimental settings. It's important to note that Zymosan itself is not a medical condition or disease, but rather a research reagent with potential applications in understanding human health and disease.

Acetates, in a medical context, most commonly refer to compounds that contain the acetate group, which is an functional group consisting of a carbon atom bonded to two hydrogen atoms and an oxygen atom (-COO-). An example of an acetate is sodium acetate (CH3COONa), which is a salt formed from acetic acid (CH3COOH) and is often used as a buffering agent in medical solutions.

Acetates can also refer to a group of medications that contain acetate as an active ingredient, such as magnesium acetate, which is used as a laxative, or calcium acetate, which is used to treat high levels of phosphate in the blood.

In addition, acetates can also refer to a process called acetylation, which is the addition of an acetyl group (-COCH3) to a molecule. This process can be important in the metabolism and regulation of various substances within the body.

Anti-asthmatic agents are a class of medications used to prevent or alleviate the symptoms of asthma, such as wheezing, shortness of breath, and coughing. These medications work by reducing inflammation, relaxing muscles in the airways, and preventing allergic reactions that can trigger an asthma attack.

There are several types of anti-asthmatic agents, including:

1. Bronchodilators: These medications relax the muscles around the airways, making it easier to breathe. They can be short-acting or long-acting, depending on how long they work.
2. Inhaled corticosteroids: These medications reduce inflammation in the airways and help prevent asthma symptoms from occurring.
3. Leukotriene modifiers: These medications block the action of leukotrienes, chemicals that contribute to inflammation and narrowing of the airways.
4. Combination therapies: Some anti-asthmatic agents combine different types of medications, such as a bronchodilator and an inhaled corticosteroid, into one inhaler.
5. Biologics: These are newer types of anti-asthmatic agents that target specific molecules involved in the inflammatory response in asthma. They are usually given by injection.

It's important to note that different people with asthma may require different medications or combinations of medications to manage their symptoms effectively. Therefore, it is essential to work closely with a healthcare provider to determine the best treatment plan for each individual.

15-Oxoprostaglandin 13-Reductase is an enzyme that catalyzes the reduction of 15-keto prostaglandins to 13,14-dihydro-15-keto prostaglandins. This enzyme plays a role in the metabolism and deactivation of prostaglandins, which are hormone-like substances that are involved in various physiological processes such as inflammation, blood flow regulation, and labor induction. The reduction of 15-keto prostaglandins to 13,14-dihydro-15-keto prostaglandins by 15-Oxoprostaglandin 13-Reductase results in the loss of biological activity of these prostaglandins.

Eicosanoic acids are a type of fatty acid that contains 20 carbon atoms. They can be further classified into subgroups based on the presence and location of double bonds in their chemical structure. The most well-known eicosanoic acids include arachidonic acid (an omega-6 fatty acid with four double bonds), eicosapentaenoic acid (an omega-3 fatty acid with five double bonds), and docosahexaenoic acid (an omega-3 fatty acid with six double bonds). These fatty acids play important roles in various physiological processes, including inflammation, blood clotting, and cell signaling. They can be found in a variety of foods, such as fish, nuts, and seeds, and are also available as dietary supplements.

Eosinophils are a type of white blood cell that play an important role in the body's immune response. They are produced in the bone marrow and released into the bloodstream, where they can travel to different tissues and organs throughout the body. Eosinophils are characterized by their granules, which contain various proteins and enzymes that are toxic to parasites and can contribute to inflammation.

Eosinophils are typically associated with allergic reactions, asthma, and other inflammatory conditions. They can also be involved in the body's response to certain infections, particularly those caused by parasites such as worms. In some cases, elevated levels of eosinophils in the blood or tissues (a condition called eosinophilia) can indicate an underlying medical condition, such as a parasitic infection, autoimmune disorder, or cancer.

Eosinophils are named for their staining properties - they readily take up eosin dye, which is why they appear pink or red under the microscope. They make up only about 1-6% of circulating white blood cells in healthy individuals, but their numbers can increase significantly in response to certain triggers.

High-performance liquid chromatography (HPLC) is a type of chromatography that separates and analyzes compounds based on their interactions with a stationary phase and a mobile phase under high pressure. The mobile phase, which can be a gas or liquid, carries the sample mixture through a column containing the stationary phase.

In HPLC, the mobile phase is a liquid, and it is pumped through the column at high pressures (up to several hundred atmospheres) to achieve faster separation times and better resolution than other types of liquid chromatography. The stationary phase can be a solid or a liquid supported on a solid, and it interacts differently with each component in the sample mixture, causing them to separate as they travel through the column.

HPLC is widely used in analytical chemistry, pharmaceuticals, biotechnology, and other fields to separate, identify, and quantify compounds present in complex mixtures. It can be used to analyze a wide range of substances, including drugs, hormones, vitamins, pigments, flavors, and pollutants. HPLC is also used in the preparation of pure samples for further study or use.

Autacoids are endogenous substances that are released by various cells in the body and have a localized, hormone-like effect on nearby tissues. They include chemicals such as histamine, serotonin (5-HT), prostaglandins, leukotrienes, and bradykinin. Autacoids are involved in various physiological processes, including inflammation, pain perception, smooth muscle contraction, and blood vessel dilation or constriction. They often act as mediators of the immune response and can contribute to the symptoms of allergies, asthma, and other medical conditions.

Chemotaxis, Leukocyte is the movement of leukocytes (white blood cells) towards a higher concentration of a particular chemical substance, known as a chemotactic factor. This process plays a crucial role in the immune system's response to infection and injury.

When there is an infection or tissue damage, certain cells release chemotactic factors, which are small molecules or proteins that can attract leukocytes to the site of inflammation. Leukocytes have receptors on their surface that can detect these chemotactic factors and move towards them through a process called chemotaxis.

Once they reach the site of inflammation, leukocytes can help eliminate pathogens or damaged cells by phagocytosis (engulfing and destroying) or releasing toxic substances that kill the invading microorganisms. Chemotaxis is an essential part of the immune system's defense mechanisms and helps to maintain tissue homeostasis and prevent the spread of infection.

Asthma is a chronic respiratory disease characterized by inflammation and narrowing of the airways, leading to symptoms such as wheezing, coughing, shortness of breath, and chest tightness. The airway obstruction in asthma is usually reversible, either spontaneously or with treatment.

The underlying cause of asthma involves a combination of genetic and environmental factors that result in hypersensitivity of the airways to certain triggers, such as allergens, irritants, viruses, exercise, and emotional stress. When these triggers are encountered, the airways constrict due to smooth muscle spasm, swell due to inflammation, and produce excess mucus, leading to the characteristic symptoms of asthma.

Asthma is typically managed with a combination of medications that include bronchodilators to relax the airway muscles, corticosteroids to reduce inflammation, and leukotriene modifiers or mast cell stabilizers to prevent allergic reactions. Avoiding triggers and monitoring symptoms are also important components of asthma management.

There are several types of asthma, including allergic asthma, non-allergic asthma, exercise-induced asthma, occupational asthma, and nocturnal asthma, each with its own set of triggers and treatment approaches. Proper diagnosis and management of asthma can help prevent exacerbations, improve quality of life, and reduce the risk of long-term complications.

I must clarify that the term "Guinea Pigs" is not typically used in medical definitions. However, in colloquial or informal language, it may refer to people who are used as the first to try out a new medical treatment or drug. This is known as being a "test subject" or "in a clinical trial."

In the field of scientific research, particularly in studies involving animals, guinea pigs are small rodents that are often used as experimental subjects due to their size, cost-effectiveness, and ease of handling. They are not actually pigs from Guinea, despite their name's origins being unclear. However, they do not exactly fit the description of being used in human medical experiments.

Masoprocol is not a medication that has an established or widely accepted medical definition in the field of pharmacology or clinical medicine. It may refer to a chemical compound with the name 5-n-butyl-2-benzoxazolinone, which has been studied for its potential anti-cancer properties. However, it is not currently approved by regulatory agencies such as the U.S. Food and Drug Administration (FDA) for use in medical treatments.

Therefore, it's important to consult with healthcare professionals or reliable medical sources for information regarding medications and their uses, rather than relying on unverified or obscure sources.

Dipeptidases are a group of enzymes that break down dipeptides, which are composed of two amino acids joined by a peptide bond. These enzymes catalyze the hydrolysis of dipeptides into individual amino acids, helping to facilitate their absorption and utilization in the body. Dipeptidases can be found on the brush border membrane of the small intestine, as well as in various tissues and organs, such as the kidneys, liver, and pancreas. They play a crucial role in protein metabolism and maintaining amino acid homeostasis within the body.

Mast cells are a type of white blood cell that are found in connective tissues throughout the body, including the skin, respiratory tract, and gastrointestinal tract. They play an important role in the immune system and help to defend the body against pathogens by releasing chemicals such as histamine, heparin, and leukotrienes, which help to attract other immune cells to the site of infection or injury. Mast cells also play a role in allergic reactions, as they release histamine and other chemicals in response to exposure to an allergen, leading to symptoms such as itching, swelling, and redness. They are derived from hematopoietic stem cells in the bone marrow and mature in the tissues where they reside.

Tosyl compounds are organic compounds that contain the tosyl group (p-toluenesulfonyl, -SO2C6H4CH3) as a substituent. The tosyl group is a protecting group or a good leaving group in organic reactions. Tosyl compounds are often prepared by reacting alcohols or amines with p-toluenesulfonyl chloride (TsCl) in the presence of a base.

The general formula for a tosyl compound can be represented as R-OTs, where R represents an organic group such as an alkyl, aryl, or heteroaryl group. Tosyl compounds are widely used in organic synthesis due to their versatility and reactivity.

Basophils are a type of white blood cell that are part of the immune system. They are granulocytes, which means they contain granules filled with chemicals that can be released in response to an infection or inflammation. Basophils are relatively rare, making up less than 1% of all white blood cells.

When basophils become activated, they release histamine and other chemical mediators that can contribute to allergic reactions, such as itching, swelling, and redness. They also play a role in inflammation, helping to recruit other immune cells to the site of an infection or injury.

Basophils can be identified under a microscope based on their characteristic staining properties. They are typically smaller than other granulocytes, such as neutrophils and eosinophils, and have a multi-lobed nucleus with dark purple-staining granules in the cytoplasm.

While basophils play an important role in the immune response, abnormal levels of basophils can be associated with various medical conditions, such as allergies, infections, and certain types of leukemia.

Dinoprostone is a prostaglandin E2 analog used in medical practice for the induction of labor and ripening of the cervix in pregnant women. It is available in various forms, including vaginal suppositories, gel, and tablets. Dinoprostone works by stimulating the contraction of uterine muscles and promoting cervical dilation, which helps in facilitating a successful delivery.

It's important to note that dinoprostone should only be administered under the supervision of a healthcare professional, as its use is associated with certain risks and side effects, including uterine hyperstimulation, fetal distress, and maternal infection. The dosage and duration of treatment are carefully monitored to minimize these risks and ensure the safety of both the mother and the baby.

Glutathione transferases (GSTs) are a group of enzymes involved in the detoxification of xenobiotics and endogenous compounds. They facilitate the conjugation of these compounds with glutathione, a tripeptide consisting of cysteine, glutamic acid, and glycine, which results in more water-soluble products that can be easily excreted from the body.

GSTs play a crucial role in protecting cells against oxidative stress and chemical injury by neutralizing reactive electrophilic species and peroxides. They are found in various tissues, including the liver, kidneys, lungs, and intestines, and are classified into several families based on their structure and function.

Abnormalities in GST activity have been associated with increased susceptibility to certain diseases, such as cancer, neurological disorders, and respiratory diseases. Therefore, GSTs have become a subject of interest in toxicology, pharmacology, and clinical research.

Thromboxane B2 (TXB2) is a stable metabolite of thromboxane A2 (TXA2), which is a potent vasoconstrictor and platelet aggregator synthesized by activated platelets. TXA2 has a very short half-life, quickly undergoing spontaneous conversion to the more stable TXB2.

TXB2 itself does not have significant biological activity but serves as a marker for TXA2 production in various physiological and pathophysiological conditions, such as thrombosis, inflammation, and atherosclerosis. It can be measured in blood or other bodily fluids to assess platelet activation and the status of hemostatic and inflammatory processes.

Aminopeptidases are a group of enzymes that catalyze the removal of amino acids from the N-terminus of polypeptides and proteins. They play important roles in various biological processes, including protein degradation, processing, and activation. Aminopeptidases are classified based on their specificity for different types of amino acids and the mechanism of their action. Some of the well-known aminopeptidases include leucine aminopeptidase, alanyl aminopeptidase, and arginine aminopeptidase. They are widely distributed in nature and found in various tissues and organisms, including bacteria, plants, and animals. In humans, aminopeptidases are involved in several physiological functions, such as digestion, immune response, and blood pressure regulation.

Complement C5a is a protein fragment that is generated during the activation of the complement system, which is a part of the immune system. The complement system helps to eliminate pathogens and damaged cells from the body by tagging them for destruction and attracting immune cells to the site of infection or injury.

C5a is formed when the fifth component of the complement system (C5) is cleaved into two smaller fragments, C5a and C5b, during the complement activation cascade. C5a is a potent pro-inflammatory mediator that can attract and activate various immune cells, such as neutrophils, monocytes, and eosinophils, to the site of infection or injury. It can also increase vascular permeability, promote the release of histamine, and induce the production of reactive oxygen species, all of which contribute to the inflammatory response.

However, excessive or uncontrolled activation of the complement system and generation of C5a can lead to tissue damage and inflammation, contributing to the pathogenesis of various diseases, such as sepsis, acute respiratory distress syndrome (ARDS), and autoimmune disorders. Therefore, targeting C5a or its receptors has been explored as a potential therapeutic strategy for these conditions.

Chromones are a type of chemical compound that contain a benzopyran ring, which is a structural component made up of a benzene ring fused to a pyran ring. They can be found in various plants and have been used in medicine for their anti-inflammatory, antimicrobial, and antitussive (cough suppressant) properties. Some chromones are also known to have estrogenic activity and have been studied for their potential use in hormone replacement therapy. Additionally, some synthetic chromones have been developed as drugs for the treatment of asthma and other respiratory disorders.

Chemotactic factors are substances that attract or repel cells, particularly immune cells, by stimulating directional movement in response to a chemical gradient. These factors play a crucial role in the body's immune response and inflammation process. They include:

1. Chemokines: A family of small signaling proteins that direct the migration of immune cells to sites of infection or tissue damage.
2. Cytokines: A broad category of signaling molecules that mediate and regulate immunity, inflammation, and hematopoiesis. Some cytokines can also act as chemotactic factors.
3. Complement components: Cleavage products of the complement system can attract immune cells to the site of infection or tissue injury.
4. Growth factors: Certain growth factors, like colony-stimulating factors (CSFs), can stimulate the migration and proliferation of specific cell types.
5. Lipid mediators: Products derived from arachidonic acid metabolism, such as leukotrienes and prostaglandins, can also act as chemotactic factors.
6. Formyl peptides: Bacterial-derived formylated peptides can attract and activate neutrophils during an infection.
7. Extracellular matrix (ECM) components: Fragments of ECM proteins, like collagen and fibronectin, can serve as chemotactic factors for immune cells.

These factors help orchestrate the immune response by guiding the movement of immune cells to specific locations in the body where they are needed.

Glycols are a type of organic compound that contain two hydroxyl (OH) groups attached to adjacent carbon atoms. They are colorless, odorless, and have a sweet taste. The most common glycols are ethylene glycol and propylene glycol. Ethylene glycol is widely used as an automotive antifreeze and in the manufacture of polyester fibers and resins, while propylene glycol is used as a food additive, in pharmaceuticals, and as a solvent in various industries. Glycols are also used as a coolant, humectant, and in the production of unsaturated polyester resins. Exposure to high levels of glycols can cause irritation to the eyes, skin, and respiratory tract, and ingestion can be harmful or fatal.

In the context of medicine and pharmacology, "kinetics" refers to the study of how a drug moves throughout the body, including its absorption, distribution, metabolism, and excretion (often abbreviated as ADME). This field is called "pharmacokinetics."

1. Absorption: This is the process of a drug moving from its site of administration into the bloodstream. Factors such as the route of administration (e.g., oral, intravenous, etc.), formulation, and individual physiological differences can affect absorption.

2. Distribution: Once a drug is in the bloodstream, it gets distributed throughout the body to various tissues and organs. This process is influenced by factors like blood flow, protein binding, and lipid solubility of the drug.

3. Metabolism: Drugs are often chemically modified in the body, typically in the liver, through processes known as metabolism. These changes can lead to the formation of active or inactive metabolites, which may then be further distributed, excreted, or undergo additional metabolic transformations.

4. Excretion: This is the process by which drugs and their metabolites are eliminated from the body, primarily through the kidneys (urine) and the liver (bile).

Understanding the kinetics of a drug is crucial for determining its optimal dosing regimen, potential interactions with other medications or foods, and any necessary adjustments for special populations like pediatric or geriatric patients, or those with impaired renal or hepatic function.

Bronchoconstriction is a medical term that refers to the narrowing of the airways in the lungs (the bronchi and bronchioles) due to the contraction of the smooth muscles surrounding them. This constriction can cause difficulty breathing, wheezing, coughing, and shortness of breath, which are common symptoms of asthma and other respiratory conditions.

Bronchoconstriction can be triggered by a variety of factors, including allergens, irritants, cold air, exercise, and emotional stress. In some cases, it may also be caused by certain medications, such as beta-blockers or nonsteroidal anti-inflammatory drugs (NSAIDs). Treatment for bronchoconstriction typically involves the use of bronchodilators, which are medications that help to relax the smooth muscles around the airways and widen them, making it easier to breathe.

Ionophores are compounds that have the ability to form complexes with ions and facilitate their transportation across biological membranes. They can be either organic or inorganic molecules, and they play important roles in various physiological processes, including ion homeostasis, signal transduction, and antibiotic activity. In medicine and research, ionophores are used as tools to study ion transport, modulate cellular functions, and as therapeutic agents, especially in the treatment of bacterial and fungal infections.

Histamine release is the process by which mast cells and basophils (types of white blood cells) release histamine, a type of chemical messenger or mediator, into the surrounding tissue fluid in response to an antigen-antibody reaction. This process is a key part of the body's immune response to foreign substances, such as allergens, and helps to initiate local inflammation, increase blood flow, and recruit other immune cells to the site of the reaction.

Histamine release can also occur in response to certain medications, physical trauma, or other stimuli. When histamine is released in large amounts, it can cause symptoms such as itching, sneezing, runny nose, watery eyes, and hives. In severe cases, it can lead to anaphylaxis, a life-threatening allergic reaction that requires immediate medical attention.

A dose-response relationship in the context of drugs refers to the changes in the effects or symptoms that occur as the dose of a drug is increased or decreased. Generally, as the dose of a drug is increased, the severity or intensity of its effects also increases. Conversely, as the dose is decreased, the effects of the drug become less severe or may disappear altogether.

The dose-response relationship is an important concept in pharmacology and toxicology because it helps to establish the safe and effective dosage range for a drug. By understanding how changes in the dose of a drug affect its therapeutic and adverse effects, healthcare providers can optimize treatment plans for their patients while minimizing the risk of harm.

The dose-response relationship is typically depicted as a curve that shows the relationship between the dose of a drug and its effect. The shape of the curve may vary depending on the drug and the specific effect being measured. Some drugs may have a steep dose-response curve, meaning that small changes in the dose can result in large differences in the effect. Other drugs may have a more gradual dose-response curve, where larger changes in the dose are needed to produce significant effects.

In addition to helping establish safe and effective dosages, the dose-response relationship is also used to evaluate the potential therapeutic benefits and risks of new drugs during clinical trials. By systematically testing different doses of a drug in controlled studies, researchers can identify the optimal dosage range for the drug and assess its safety and efficacy.

Histamine is defined as a biogenic amine that is widely distributed throughout the body and is involved in various physiological functions. It is derived primarily from the amino acid histidine by the action of histidine decarboxylase. Histamine is stored in granules (along with heparin and proteases) within mast cells and basophils, and is released upon stimulation or degranulation of these cells.

Once released into the tissues and circulation, histamine exerts a wide range of pharmacological actions through its interaction with four types of G protein-coupled receptors (H1, H2, H3, and H4 receptors). Histamine's effects are diverse and include modulation of immune responses, contraction and relaxation of smooth muscle, increased vascular permeability, stimulation of gastric acid secretion, and regulation of neurotransmission.

Histamine is also a potent mediator of allergic reactions and inflammation, causing symptoms such as itching, sneezing, runny nose, and wheezing. Antihistamines are commonly used to block the actions of histamine at H1 receptors, providing relief from these symptoms.

12-Hydroxy-5,8,10,14-eicosatetraenoic acid (12-HETE) is a type of fatty acid that is produced in the body as a result of the metabolism of arachidonic acid, which is an omega-6 fatty acid that is found in the membranes of cells throughout the body.

12-HETE is synthesized by the enzyme 12-lipoxygenase (12-LOX), which adds a hydroxyl group (-OH) to the twelfth carbon atom of arachidonic acid. This lipid mediator plays a role in various physiological and pathophysiological processes, including inflammation, immune response, and cancer development.

Increased levels of 12-HETE have been found in several diseases, such as atherosclerosis, asthma, and cancer, suggesting that it may contribute to the development and progression of these conditions. However, further research is needed to fully understand the role of 12-HETE in human health and disease.

Phospholipases A are a group of enzymes that hydrolyze phospholipids into fatty acids and lysophospholipids by cleaving the ester bond at the sn-1 or sn-2 position of the glycerol backbone. There are three main types of Phospholipases A:

* Phospholipase A1 (PLA1): This enzyme specifically hydrolyzes the ester bond at the sn-1 position, releasing a free fatty acid and a lysophospholipid.
* Phospholipase A2 (PLA2): This enzyme specifically hydrolyzes the ester bond at the sn-2 position, releasing a free fatty acid (often arachidonic acid, which is a precursor for eicosanoids) and a lysophospholipid.
* Phospholipase A/B (PLA/B): This enzyme has both PLA1 and PLA2 activity and can hydrolyze the ester bond at either the sn-1 or sn-2 position.

Phospholipases A play important roles in various biological processes, including cell signaling, membrane remodeling, and host defense. They are also involved in several diseases, such as atherosclerosis, neurodegenerative disorders, and cancer.

"Cells, cultured" is a medical term that refers to cells that have been removed from an organism and grown in controlled laboratory conditions outside of the body. This process is called cell culture and it allows scientists to study cells in a more controlled and accessible environment than they would have inside the body. Cultured cells can be derived from a variety of sources, including tissues, organs, or fluids from humans, animals, or cell lines that have been previously established in the laboratory.

Cell culture involves several steps, including isolation of the cells from the tissue, purification and characterization of the cells, and maintenance of the cells in appropriate growth conditions. The cells are typically grown in specialized media that contain nutrients, growth factors, and other components necessary for their survival and proliferation. Cultured cells can be used for a variety of purposes, including basic research, drug development and testing, and production of biological products such as vaccines and gene therapies.

It is important to note that cultured cells may behave differently than they do in the body, and results obtained from cell culture studies may not always translate directly to human physiology or disease. Therefore, it is essential to validate findings from cell culture experiments using additional models and ultimately in clinical trials involving human subjects.

Leukocytes, also known as white blood cells (WBCs), are a crucial component of the human immune system. They are responsible for protecting the body against infections and foreign substances. Leukocytes are produced in the bone marrow and circulate throughout the body in the bloodstream and lymphatic system.

There are several types of leukocytes, including:

1. Neutrophils - These are the most abundant type of leukocyte and are primarily responsible for fighting bacterial infections. They contain enzymes that can destroy bacteria.
2. Lymphocytes - These are responsible for producing antibodies and destroying virus-infected cells, as well as cancer cells. There are two main types of lymphocytes: B-lymphocytes and T-lymphocytes.
3. Monocytes - These are the largest type of leukocyte and help to break down and remove dead or damaged tissues, as well as microorganisms.
4. Eosinophils - These play a role in fighting parasitic infections and are also involved in allergic reactions and inflammation.
5. Basophils - These release histamine and other chemicals that cause inflammation in response to allergens or irritants.

An abnormal increase or decrease in the number of leukocytes can indicate an underlying medical condition, such as an infection, inflammation, or a blood disorder.

Phospholipase A2 (PLA2) is a type of enzyme that catalyzes the hydrolysis of the sn-2 ester bond in glycerophospholipids, releasing free fatty acids, such as arachidonic acid, and lysophospholipids. These products are important precursors for the biosynthesis of various signaling molecules, including eicosanoids, platelet-activating factor (PAF), and lipoxins, which play crucial roles in inflammation, immunity, and other cellular processes.

Phospholipases A2 are classified into several groups based on their structure, mechanism of action, and cellular localization. The secreted PLA2s (sPLA2s) are found in extracellular fluids and are characterized by a low molecular weight, while the calcium-dependent cytosolic PLA2s (cPLA2s) are larger proteins that reside within cells.

Abnormal regulation or activity of Phospholipase A2 has been implicated in various pathological conditions, such as inflammation, neurodegenerative diseases, and cancer. Therefore, understanding the biology and function of these enzymes is essential for developing novel therapeutic strategies to target these disorders.

Phenylpropionates are a group of organic compounds that contain a phenyl group and a propionate group. In the context of pharmaceuticals, phenylpropionates often refer to a specific type of esterified hormone, such as testosterone phenylpropionate or nandrolone phenylpropionate. These esters are used in some forms of anabolic-androgenic steroids and are created by attaching a phenylpropionate group to the parent hormone molecule. This modification allows for a slower release and longer duration of action when administered intramuscularly.

It is important to note that these substances have medical uses, but they also carry risks and potential side effects, especially when used inappropriately or without medical supervision. They are controlled substances in many countries due to their potential for misuse and abuse.

A lung is a pair of spongy, elastic organs in the chest that work together to enable breathing. They are responsible for taking in oxygen and expelling carbon dioxide through the process of respiration. The left lung has two lobes, while the right lung has three lobes. The lungs are protected by the ribcage and are covered by a double-layered membrane called the pleura. The trachea divides into two bronchi, which further divide into smaller bronchioles, leading to millions of tiny air sacs called alveoli, where the exchange of gases occurs.

Complement C5a, des-Arginine is a derivative of the complement component C5a. The complement system is a group of proteins that are part of the body's immune defense against foreign invaders such as bacteria and viruses. When activated, the complement system can help to eliminate pathogens by attracting immune cells to the site of infection, promoting inflammation, and directly killing the pathogen.

C5a is a small protein that is generated when the complement component C5 is cleaved during the activation of the complement system. C5a is a potent anaphylatoxin, which means it can cause the release of histamine from mast cells and basophils, leading to increased vascular permeability, smooth muscle contraction, and recruitment of immune cells to the site of infection.

Des-Arginine refers to the removal of an arginine residue from the C-terminus of C5a. This modified form of C5a is known as C5a-desArg and has reduced pro-inflammatory activity compared to intact C5a. However, it can still contribute to the regulation of the immune response by interacting with specific receptors on immune cells.

In summary, Complement C5a, des-Arginine is a derivative of the complement component C5a that has reduced pro-inflammatory activity due to the removal of an arginine residue from its C-terminus.

Prostaglandin D2 (PGD2) is a type of prostaglandin, which is a group of lipid compounds that are derived enzymatically from arachidonic acid and have diverse hormone-like effects in various tissues. PGD2 is one of the most abundant prostaglandins produced in the human body and is primarily synthesized and released by activated mast cells, which are a type of immune cell found in various tissues throughout the body.

PGD2 has a wide range of biological activities, including vasodilation, bronchoconstriction, and modulation of immune responses. It also plays important roles in regulating sleep and wakefulness, as well as in the development of allergic inflammation and other inflammatory processes. PGD2 exerts its effects by binding to specific G protein-coupled receptors, including the DP1 and CRTH2 receptors, which are expressed on various cell types throughout the body.

In addition to its role in normal physiological processes, PGD2 has also been implicated in a number of pathological conditions, including asthma, rhinitis, dermatitis, and certain types of cancer. As such, drugs that target the synthesis or action of PGD2 have been developed as potential therapeutic agents for these conditions.

Eicosapentaenoic acid (EPA) is a type of omega-3 fatty acid that is found in fish and some algae. It is a 20-carbon long polyunsaturated fatty acid with five double bonds, and has the chemical formula C20:5 n-3. EPA is an essential fatty acid, meaning that it cannot be produced by the human body and must be obtained through the diet.

EPA is a precursor to a group of hormone-like substances called eicosanoids, which include prostaglandins, thromboxanes, and leukotrienes. These compounds play important roles in regulating various physiological processes, such as inflammation, blood clotting, and immune function.

EPA has been studied for its potential health benefits, including reducing inflammation, lowering the risk of heart disease, and improving symptoms of depression. It is often taken as a dietary supplement in the form of fish oil or algal oil. However, it is important to note that while some studies have suggested potential health benefits of EPA, more research is needed to confirm these effects and establish recommended dosages.

Indole is not strictly a medical term, but it is a chemical compound that can be found in the human body and has relevance to medical and biological research. Indoles are organic compounds that contain a bicyclic structure consisting of a six-membered benzene ring fused to a five-membered pyrrole ring.

In the context of medicine, indoles are particularly relevant due to their presence in certain hormones and other biologically active molecules. For example, the neurotransmitter serotonin contains an indole ring, as does the hormone melatonin. Indoles can also be found in various plant-based foods, such as cruciferous vegetables (e.g., broccoli, kale), and have been studied for their potential health benefits.

Some indoles, like indole-3-carbinol and diindolylmethane, are found in these vegetables and can have anti-cancer properties by modulating estrogen metabolism, reducing inflammation, and promoting cell death (apoptosis) in cancer cells. However, it is essential to note that further research is needed to fully understand the potential health benefits and risks associated with indoles.

"Bronchi" are a pair of airways in the respiratory system that branch off from the trachea (windpipe) and lead to the lungs. They are responsible for delivering oxygen-rich air to the lungs and removing carbon dioxide during exhalation. The right bronchus is slightly larger and more vertical than the left, and they further divide into smaller branches called bronchioles within the lungs. Any abnormalities or diseases affecting the bronchi can impact lung function and overall respiratory health.

Hydroxyurea is an antimetabolite drug that is primarily used in the treatment of myeloproliferative disorders such as chronic myelogenous leukemia (CML), essential thrombocythemia, and polycythemia vera. It works by interfering with the synthesis of DNA, which inhibits the growth of cancer cells.

In addition to its use in cancer therapy, hydroxyurea is also used off-label for the management of sickle cell disease. In this context, it helps to reduce the frequency and severity of painful vaso-occlusive crises by increasing the production of fetal hemoglobin (HbF), which decreases the formation of sickled red blood cells.

The medical definition of hydroxyurea is:

A hydantoin derivative and antimetabolite that inhibits ribonucleoside diphosphate reductase, thereby interfering with DNA synthesis. It has been used as an antineoplastic agent, particularly in the treatment of myeloproliferative disorders, and more recently for the management of sickle cell disease to reduce the frequency and severity of painful vaso-occlusive crises by increasing fetal hemoglobin production.

Carboxylic acids are organic compounds that contain a carboxyl group, which is a functional group made up of a carbon atom doubly bonded to an oxygen atom and single bonded to a hydroxyl group. The general formula for a carboxylic acid is R-COOH, where R represents the rest of the molecule.

Carboxylic acids can be found in various natural sources such as in fruits, vegetables, and animal products. Some common examples of carboxylic acids include formic acid (HCOOH), acetic acid (CH3COOH), propionic acid (C2H5COOH), and butyric acid (C3H7COOH).

Carboxylic acids have a variety of uses in industry, including as food additives, pharmaceuticals, and industrial chemicals. They are also important intermediates in the synthesis of other organic compounds. In the body, carboxylic acids play important roles in metabolism and energy production.

Propionates, in a medical context, most commonly refer to a group of medications that are used as topical creams or gels to treat fungal infections of the skin. Propionic acid and its salts, such as propionate, are the active ingredients in these medications. They work by inhibiting the growth of fungi, which causes the infection. Common examples of propionate-containing medications include creams used to treat athlete's foot, ringworm, and jock itch.

It is important to note that there are many different types of medications and compounds that contain the word "propionate" in their name, as it refers to a specific chemical structure. However, in a medical context, it most commonly refers to antifungal creams or gels.

Fatty alcohols, also known as long-chain alcohols or long-chain fatty alcohols, are a type of fatty compound that contains a hydroxyl group (-OH) and a long alkyl chain. They are typically derived from natural sources such as plant and animal fats and oils, and can also be synthetically produced.

Fatty alcohols can vary in chain length, typically containing between 8 and 30 carbon atoms. They are commonly used in a variety of industrial and consumer products, including detergents, emulsifiers, lubricants, and personal care products. In the medical field, fatty alcohols may be used as ingredients in certain medications or topical treatments.

Cysteine is a semi-essential amino acid, which means that it can be produced by the human body under normal circumstances, but may need to be obtained from external sources in certain conditions such as illness or stress. Its chemical formula is HO2CCH(NH2)CH2SH, and it contains a sulfhydryl group (-SH), which allows it to act as a powerful antioxidant and participate in various cellular processes.

Cysteine plays important roles in protein structure and function, detoxification, and the synthesis of other molecules such as glutathione, taurine, and coenzyme A. It is also involved in wound healing, immune response, and the maintenance of healthy skin, hair, and nails.

Cysteine can be found in a variety of foods, including meat, poultry, fish, dairy products, eggs, legumes, nuts, seeds, and some grains. It is also available as a dietary supplement and can be used in the treatment of various medical conditions such as liver disease, bronchitis, and heavy metal toxicity. However, excessive intake of cysteine may have adverse effects on health, including gastrointestinal disturbances, nausea, vomiting, and headaches.

Indomethacin is a non-steroidal anti-inflammatory drug (NSAID) that is commonly used to reduce pain, inflammation, and fever. It works by inhibiting the activity of certain enzymes in the body, including cyclooxygenase (COX), which plays a role in producing prostaglandins, chemicals involved in the inflammatory response.

Indomethacin is available in various forms, such as capsules, suppositories, and injectable solutions, and is used to treat a wide range of conditions, including rheumatoid arthritis, osteoarthritis, ankylosing spondylitis, gout, and bursitis. It may also be used to relieve pain and reduce fever in other conditions, such as dental procedures or after surgery.

Like all NSAIDs, indomethacin can have side effects, including stomach ulcers, bleeding, and kidney damage, especially when taken at high doses or for long periods of time. It may also increase the risk of heart attack and stroke. Therefore, it is important to use indomethacin only as directed by a healthcare provider and to report any unusual symptoms or side effects promptly.

Spectrophotometry, Ultraviolet (UV-Vis) is a type of spectrophotometry that measures how much ultraviolet (UV) and visible light is absorbed or transmitted by a sample. It uses a device called a spectrophotometer to measure the intensity of light at different wavelengths as it passes through a sample. The resulting data can be used to determine the concentration of specific components within the sample, identify unknown substances, or evaluate the physical and chemical properties of materials.

UV-Vis spectroscopy is widely used in various fields such as chemistry, biology, pharmaceuticals, and environmental science. It can detect a wide range of substances including organic compounds, metal ions, proteins, nucleic acids, and dyes. The technique is non-destructive, meaning that the sample remains unchanged after the measurement.

In UV-Vis spectroscopy, the sample is placed in a cuvette or other container, and light from a source is directed through it. The light then passes through a monochromator, which separates it into its component wavelengths. The monochromatic light is then directed through the sample, and the intensity of the transmitted or absorbed light is measured by a detector.

The resulting absorption spectrum can provide information about the concentration and identity of the components in the sample. For example, if a compound has a known absorption maximum at a specific wavelength, its concentration can be determined by measuring the absorbance at that wavelength and comparing it to a standard curve.

Overall, UV-Vis spectrophotometry is a versatile and powerful analytical technique for quantitative and qualitative analysis of various samples in different fields.

Multidrug Resistance-Associated Proteins (MRPs) are a subfamily of ATP-binding cassette (ABC) transporter proteins that play a crucial role in the efflux of various substrates, including drugs and organic anions, out of cells. They are located in the plasma membrane of many cell types, including epithelial cells in the liver, intestine, kidney, and blood-brain barrier.

MRPs are known to transport a wide range of molecules, such as glutathione conjugates, bilirubin, bile acids, and various clinical drugs. One of the most well-known MRPs is MRP1 (ABCC1), which was initially identified in drug-resistant tumor cells. MRP1 can confer resistance to chemotherapeutic agents by actively pumping them out of cancer cells, thereby reducing their intracellular concentration and effectiveness.

The activity of MRPs can have significant implications for the pharmacokinetics and pharmacodynamics of drugs, as they can affect drug absorption, distribution, metabolism, and excretion (ADME). Understanding the function and regulation of MRPs is essential for developing strategies to overcome multidrug resistance in cancer therapy and optimizing drug dosing regimens in various clinical settings.

Dicarboxylic acids are organic compounds containing two carboxyl groups (-COOH) in their molecular structure. The general formula for dicarboxylic acids is HOOC-R-COOH, where R represents a hydrocarbon chain or a functional group.

The presence of two carboxyl groups makes dicarboxylic acids stronger acids than monocarboxylic acids (compounds containing only one -COOH group). This is because the second carboxyl group contributes to the acidity of the molecule, allowing it to donate two protons in solution.

Examples of dicarboxylic acids include oxalic acid (HOOC-COOH), malonic acid (CH2(COOH)2), succinic acid (HOOC-CH2-CH2-COOH), glutaric acid (HOOC-(CH2)3-COOH), and adipic acid (HOOC-(CH2)4-COOH). These acids have various industrial applications, such as in the production of polymers, dyes, and pharmaceuticals.

Calcium is an essential mineral that is vital for various physiological processes in the human body. The medical definition of calcium is as follows:

Calcium (Ca2+) is a crucial cation and the most abundant mineral in the human body, with approximately 99% of it found in bones and teeth. It plays a vital role in maintaining structural integrity, nerve impulse transmission, muscle contraction, hormonal secretion, blood coagulation, and enzyme activation.

Calcium homeostasis is tightly regulated through the interplay of several hormones, including parathyroid hormone (PTH), calcitonin, and vitamin D. Dietary calcium intake, absorption, and excretion are also critical factors in maintaining optimal calcium levels in the body.

Hypocalcemia refers to low serum calcium levels, while hypercalcemia indicates high serum calcium levels. Both conditions can have detrimental effects on various organ systems and require medical intervention to correct.

Pleurisy is a medical condition characterized by inflammation of the pleura, which are the thin membranes that surround the lungs and line the inside of the chest cavity. The pleura normally produce a small amount of lubricating fluid that allows for smooth movement of the lungs during breathing. However, when they become inflamed (a condition known as pleuritis), this can cause pain and difficulty breathing.

The symptoms of pleurisy may include sharp chest pain that worsens with deep breathing or coughing, shortness of breath, cough, fever, and muscle aches. The pain may be localized to one area of the chest or may radiate to other areas such as the shoulders or back.

Pleurisy can have many different causes, including bacterial or viral infections, autoimmune disorders, pulmonary embolism (a blood clot that travels to the lungs), and certain medications or chemicals. Treatment typically involves addressing the underlying cause of the inflammation, as well as managing symptoms such as pain and breathing difficulties with medications such as nonsteroidal anti-inflammatory drugs (NSAIDs) or opioids. In some cases, more invasive treatments such as thoracentesis (removal of fluid from the chest cavity) may be necessary.

Unsaturated fatty acids are a type of fatty acid that contain one or more double bonds in their carbon chain. These double bonds can be either cis or trans configurations, although the cis configuration is more common in nature. The presence of these double bonds makes unsaturated fatty acids more liquid at room temperature and less prone to spoilage than saturated fatty acids, which do not have any double bonds.

Unsaturated fatty acids can be further classified into two main categories: monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs). MUFAs contain one double bond in their carbon chain, while PUFAs contain two or more.

Examples of unsaturated fatty acids include oleic acid (a MUFA found in olive oil), linoleic acid (a PUFA found in vegetable oils), and alpha-linolenic acid (an omega-3 PUFA found in flaxseed and fish). Unsaturated fatty acids are essential nutrients for the human body, as they play important roles in various physiological processes such as membrane structure, inflammation, and blood clotting. It is recommended to consume a balanced diet that includes both MUFAs and PUFAs to maintain good health.

Arachidonate 12-lipoxygenase (also known as ALOX12 or 12S-lipoxygenase) is an enzyme that catalyzes the conversion of arachidonic acid to 12(S)-hydroperoxyeicosatetraenoic acid (12(S)-HPETE). This reaction is part of the lipoxygenase pathway, which contributes to the biosynthesis of eicosanoids, a group of signaling molecules that play important roles in inflammation and immune response.

The enzyme's function includes introducing molecular oxygen into arachidonic acid at position 12, creating a hydroperoxide group. The product, 12(S)-HPETE, can be further metabolized to various eicosanoids, such as 12-hydroxyeicosatetraenoic acid (12-HETE) and lipoxin A4, which have diverse biological activities in the body.

Arachidonate 12-lipoxygenase is expressed in various tissues, including the vascular endothelium, platelets, and immune cells like monocytes and macrophages. Its activity can contribute to the development of certain diseases, such as atherosclerosis, cancer, and inflammatory disorders. Therefore, inhibiting this enzyme has been considered as a potential therapeutic strategy for treating these conditions.

8,11,14-Eicosatrienoic acid is a type of fatty acid that contains 20 carbon atoms and three double bonds. The locations of these double bonds are at the 8th, 11th, and 14th carbon atoms, hence the name of the fatty acid. It is an omega-3 fatty acid, which means that the first double bond is located between the third and fourth carbon atoms from the methyl end of the molecule.

This particular fatty acid is not considered to be essential for human health, as it can be synthesized in the body from other fatty acids. It is a component of certain types of lipids found in animal tissues, including beef and lamb. It has been studied for its potential role in various physiological processes, such as inflammation and immune function, but its specific functions and effects on human health are not well understood.

Mast cell sarcoma is a very rare and aggressive type of cancer that arises from mast cells, which are immune cells found in various tissues throughout the body, particularly connective tissue. Mast cells play a crucial role in the body's immune response and allergic reactions by releasing histamine and other mediators.

Mast cell sarcoma is characterized by the malignant proliferation of mast cells, leading to the formation of tumors. These tumors can grow rapidly and may metastasize (spread) to other parts of the body. Unlike more common mast cell disorders such as mastocytosis, which typically affect the skin, mast cell sarcoma can occur in any part of the body.

The symptoms of mast cell sarcoma can vary widely depending on the location and extent of the tumor. Common signs and symptoms may include pain, swelling, or a palpable mass at the site of the tumor; fatigue; weight loss; and fever. Diagnosis typically involves a combination of clinical evaluation, imaging studies, and biopsy to confirm the presence of malignant mast cells.

Treatment for mast cell sarcoma is generally aggressive and may involve surgery, radiation therapy, chemotherapy, or a combination of these approaches. The prognosis for patients with this condition is often poor, with a high rate of recurrence and metastasis. As such, ongoing research is focused on developing new and more effective therapies for this rare and challenging cancer.

Benzopyrans are a class of chemical compounds that contain a benzene ring fused to a pyran ring. They are also known as chromenes. Benzopyrans can be found in various natural sources, including plants and fungi, and have been studied for their potential biological activities. Some benzopyrans have been found to have anti-inflammatory, antioxidant, and anticancer properties. However, some benzopyrans can also be toxic or have other adverse health effects, so it is important to study their properties and potential uses carefully.

"Inhalation administration" is a medical term that refers to the method of delivering medications or therapeutic agents directly into the lungs by inhaling them through the airways. This route of administration is commonly used for treating respiratory conditions such as asthma, COPD (chronic obstructive pulmonary disease), and cystic fibrosis.

Inhalation administration can be achieved using various devices, including metered-dose inhalers (MDIs), dry powder inhalers (DPIs), nebulizers, and soft-mist inhalers. Each device has its unique mechanism of delivering the medication into the lungs, but they all aim to provide a high concentration of the drug directly to the site of action while minimizing systemic exposure and side effects.

The advantages of inhalation administration include rapid onset of action, increased local drug concentration, reduced systemic side effects, and improved patient compliance due to the ease of use and non-invasive nature of the delivery method. However, proper technique and device usage are crucial for effective therapy, as incorrect usage may result in suboptimal drug deposition and therapeutic outcomes.

Passive Cutaneous Anaphylaxis (PCA) is a type of localized or cutaneous hypersensitivity reaction that occurs when an individual who has been sensitized to a particular antigen is injected with the antigen along with a dye (usually Evans blue) and subsequently intravenously administered with a foreign protein, such as horse serum, that contains antibodies (IgG) against the antigen. The IgG antibodies passively transfer to the sensitized individual and bind to the antigen at the site of injection, forming immune complexes. These immune complexes then activate the complement system, leading to the release of mediators such as histamine, which causes localized vasodilation, increased vascular permeability, and extravasation of the dye into the surrounding tissues. As a result, a blue-colored wheal or skin blanching appears at the injection site, indicating a positive PCA reaction. This test is used to detect the presence of IgG antibodies in an individual's serum and to study the mechanisms of immune complex-mediated hypersensitivity reactions.

Membrane proteins are a type of protein that are embedded in the lipid bilayer of biological membranes, such as the plasma membrane of cells or the inner membrane of mitochondria. These proteins play crucial roles in various cellular processes, including:

1. Cell-cell recognition and signaling
2. Transport of molecules across the membrane (selective permeability)
3. Enzymatic reactions at the membrane surface
4. Energy transduction and conversion
5. Mechanosensation and signal transduction

Membrane proteins can be classified into two main categories: integral membrane proteins, which are permanently associated with the lipid bilayer, and peripheral membrane proteins, which are temporarily or loosely attached to the membrane surface. Integral membrane proteins can further be divided into three subcategories based on their topology:

1. Transmembrane proteins, which span the entire width of the lipid bilayer with one or more alpha-helices or beta-barrels.
2. Lipid-anchored proteins, which are covalently attached to lipids in the membrane via a glycosylphosphatidylinositol (GPI) anchor or other lipid modifications.
3. Monotopic proteins, which are partially embedded in the membrane and have one or more domains exposed to either side of the bilayer.

Membrane proteins are essential for maintaining cellular homeostasis and are targets for various therapeutic interventions, including drug development and gene therapy. However, their structural complexity and hydrophobicity make them challenging to study using traditional biochemical methods, requiring specialized techniques such as X-ray crystallography, nuclear magnetic resonance (NMR) spectroscopy, and single-particle cryo-electron microscopy (cryo-EM).

The trachea, also known as the windpipe, is a tube-like structure in the respiratory system that connects the larynx (voice box) to the bronchi (the two branches leading to each lung). It is composed of several incomplete rings of cartilage and smooth muscle, which provide support and flexibility. The trachea plays a crucial role in directing incoming air to the lungs during inspiration and outgoing air to the larynx during expiration.

Cyclooxygenase (COX) inhibitors are a class of drugs that work by blocking the activity of cyclooxygenase enzymes, which are involved in the production of prostaglandins. Prostaglandins are hormone-like substances that play a role in inflammation, pain, and fever.

There are two main types of COX enzymes: COX-1 and COX-2. COX-1 is produced continuously in various tissues throughout the body and helps maintain the normal function of the stomach and kidneys, among other things. COX-2, on the other hand, is produced in response to inflammation and is involved in the production of prostaglandins that contribute to pain, fever, and inflammation.

COX inhibitors can be non-selective, meaning they block both COX-1 and COX-2, or selective, meaning they primarily block COX-2. Non-selective COX inhibitors include drugs such as aspirin, ibuprofen, and naproxen, while selective COX inhibitors are often referred to as coxibs and include celecoxib (Celebrex) and rofecoxib (Vioxx).

COX inhibitors are commonly used to treat pain, inflammation, and fever. However, long-term use of non-selective COX inhibitors can increase the risk of gastrointestinal side effects such as ulcers and bleeding, while selective COX inhibitors may be associated with an increased risk of cardiovascular events such as heart attack and stroke. It is important to talk to a healthcare provider about the potential risks and benefits of COX inhibitors before using them.

Group IV Phospholipases A2 (PLA2) are a subclass of the PLA2 family, which are enzymes that hydrolyze the sn-2 acyl bond of glycerophospholipids to release free fatty acids and lysophospholipids. Specifically, Group IV PLA2s are calcium-dependent enzymes that are primarily located in the cytoplasm of cells and are involved in various cellular processes such as membrane remodeling, signal transduction, and inflammation.

Group IV PLA2s can be further divided into several subgroups, including Group IVA (also known as cPLA2s) and Group IVB (also known as iPLA2s). These enzymes have distinct structural features and play different roles in cellular physiology. For example, cPLA2s are involved in the production of eicosanoids, which are signaling molecules that mediate inflammation and other responses to injury or infection. On the other hand, iPLA2s are involved in maintaining membrane homeostasis and regulating cellular energy metabolism.

Abnormal regulation of Group IV PLA2 activity has been implicated in various pathological conditions, including cancer, neurodegenerative diseases, and cardiovascular disease. Therefore, understanding the function and regulation of these enzymes is an important area of research with potential therapeutic implications.

Capillary permeability refers to the ability of substances to pass through the walls of capillaries, which are the smallest blood vessels in the body. These tiny vessels connect the arterioles and venules, allowing for the exchange of nutrients, waste products, and gases between the blood and the surrounding tissues.

The capillary wall is composed of a single layer of endothelial cells that are held together by tight junctions. The permeability of these walls varies depending on the size and charge of the molecules attempting to pass through. Small, uncharged molecules such as water, oxygen, and carbon dioxide can easily diffuse through the capillary wall, while larger or charged molecules such as proteins and large ions have more difficulty passing through.

Increased capillary permeability can occur in response to inflammation, infection, or injury, allowing larger molecules and immune cells to enter the surrounding tissues. This can lead to swelling (edema) and tissue damage if not controlled. Decreased capillary permeability, on the other hand, can lead to impaired nutrient exchange and tissue hypoxia.

Overall, the permeability of capillaries is a critical factor in maintaining the health and function of tissues throughout the body.

Histamine H1 antagonists, also known as H1 blockers or antihistamines, are a class of medications that work by blocking the action of histamine at the H1 receptor. Histamine is a chemical mediator released by mast cells and basophils in response to an allergic reaction or injury. It causes various symptoms such as itching, sneezing, runny nose, and wheal and flare reactions (hives).

H1 antagonists prevent the binding of histamine to its receptor, thereby alleviating these symptoms. They are commonly used to treat allergic conditions such as hay fever, hives, and eczema, as well as motion sickness and insomnia. Examples of H1 antagonists include diphenhydramine (Benadryl), loratadine (Claritin), cetirizine (Zyrtec), and doxylamine (Unisom).

N-Formylmethionine (fMet) is not a medical term per se, but rather a biochemical term. It is the formylated derivative of methionine, which is one of the twenty standard amino acids, and it plays a crucial role in the initiation of protein synthesis in prokaryotes and organelles of eukaryotic cells, such as mitochondria and chloroplasts.

In the context of medical research or clinical laboratory reports, you might encounter fMet in relation to bacterial infections, proteomics, or mitochondrial function. For example, formylated methionine residues on bacterial peptides can stimulate immune responses and are recognized by specific receptors on human immune cells, which can have implications for understanding infectious diseases and inflammation.

To provide a concise definition:
N-Formylmethionine (fMet) is the formylated derivative of methionine, primarily known for its role as the initiator amino acid in protein synthesis in prokaryotes and certain organelles of eukaryotic cells.

Complement C5 is a protein that plays a crucial role in the complement system, which is a part of the immune system that helps to eliminate pathogens and damaged cells from the body. The complement system is a complex series of biochemical reactions that help to identify and destroy foreign substances, such as bacteria and viruses.

Complement C5 is one of several proteins in the complement system that are activated in a cascading manner in response to an activating event, such as the binding of an antibody to a pathogen. Once activated, Complement C5 can be cleaved into two smaller proteins, C5a and C5b.

C5a is a powerful anaphylatoxin, which means it can cause the release of histamine from mast cells and basophils, leading to inflammation and increased vascular permeability. It also acts as a chemoattractant, drawing immune cells to the site of infection or injury.

C5b, on the other hand, plays a role in the formation of the membrane attack complex (MAC), which is a protein structure that can punch holes in the membranes of pathogens, leading to their lysis and destruction.

Overall, Complement C5 is an important component of the immune system's response to infection and injury, helping to eliminate pathogens and damaged cells from the body.

Cytosol refers to the liquid portion of the cytoplasm found within a eukaryotic cell, excluding the organelles and structures suspended in it. It is the site of various metabolic activities and contains a variety of ions, small molecules, and enzymes. The cytosol is where many biochemical reactions take place, including glycolysis, protein synthesis, and the regulation of cellular pH. It is also where some organelles, such as ribosomes and vesicles, are located. In contrast to the cytosol, the term "cytoplasm" refers to the entire contents of a cell, including both the cytosol and the organelles suspended within it.

Inflammation is a complex biological response of tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. It is characterized by the following signs: rubor (redness), tumor (swelling), calor (heat), dolor (pain), and functio laesa (loss of function). The process involves the activation of the immune system, recruitment of white blood cells, and release of inflammatory mediators, which contribute to the elimination of the injurious stimuli and initiation of the healing process. However, uncontrolled or chronic inflammation can also lead to tissue damage and diseases.

Aspirin-induced asthma (AIA) is a specific form of asthma that is characterized by the worsening of respiratory symptoms after ingesting aspirin or other nonsteroidal anti-inflammatory drugs (NSAIDs). AIA is also known as NSAID-exacerbated respiratory disease (NERD) or aspirin-sensitive asthma.

People with AIA typically experience bronchoconstriction, nasal congestion, and rhinorrhea after taking aspirin or other NSAIDs that inhibit cyclooxygenase-1 (COX-1). These symptoms can range from mild to severe and may occur within a few minutes to several hours after ingesting the medication.

In addition to respiratory symptoms, some people with AIA may also develop skin reactions, such as hives or angioedema, and gastrointestinal symptoms, such as abdominal pain or diarrhea. The exact mechanism by which aspirin and other NSAIDs trigger these symptoms in people with AIA is not fully understood, but it is thought to be related to an imbalance in the production of prostaglandins and leukotrienes, two types of lipid mediators that play a role in inflammation.

Avoiding aspirin and other NSAIDs is the primary treatment for AIA. In some cases, medications such as corticosteroids, leukotriene modifiers, or antihistamines may be prescribed to help manage symptoms. Desensitization therapy, which involves gradually increasing the dose of aspirin under medical supervision, may also be an option for some people with AIA who are unable to avoid NSAIDs altogether.

Granulocytes are a type of white blood cell that plays a crucial role in the body's immune system. They are called granulocytes because they contain small granules in their cytoplasm, which are filled with various enzymes and proteins that help them fight off infections and destroy foreign substances.

There are three types of granulocytes: neutrophils, eosinophils, and basophils. Neutrophils are the most abundant type and are primarily responsible for fighting bacterial infections. Eosinophils play a role in defending against parasitic infections and regulating immune responses. Basophils are involved in inflammatory reactions and allergic responses.

Granulocytes are produced in the bone marrow and released into the bloodstream, where they circulate and patrol for any signs of infection or foreign substances. When they encounter a threat, they quickly move to the site of infection or injury and release their granules to destroy the invading organisms or substances.

Abnormal levels of granulocytes in the blood can indicate an underlying medical condition, such as an infection, inflammation, or a bone marrow disorder.

Immunoglobulin E (IgE) is a type of antibody that plays a key role in the immune response to parasitic infections and allergies. It is produced by B cells in response to stimulation by antigens, such as pollen, pet dander, or certain foods. Once produced, IgE binds to receptors on the surface of mast cells and basophils, which are immune cells found in tissues and blood respectively. When an individual with IgE antibodies encounters the allergen again, the cross-linking of IgE molecules bound to the FcεRI receptor triggers the release of mediators such as histamine, leukotrienes, prostaglandins, and various cytokines from these cells. These mediators cause the symptoms of an allergic reaction, such as itching, swelling, and redness. IgE also plays a role in protecting against certain parasitic infections by activating eosinophils, which can kill the parasites.

In summary, Immunoglobulin E (IgE) is a type of antibody that plays a crucial role in the immune response to allergens and parasitic infections, it binds to receptors on the surface of mast cells and basophils, when an individual with IgE antibodies encounters the allergen again, it triggers the release of mediators from these cells causing the symptoms of an allergic reaction.

5,8,11,14-Eicosatetraynoic acid (ETYA) is a polyunsaturated fatty acid that contains four double bonds in its chemical structure. It is a non-methylene interrupted fatty acid, which means that the double bonds are separated by three methylene bridges. ETYA is not a naturally occurring fatty acid and is typically synthesized in the laboratory for research purposes.

ETYA has been used as a tool to study the biochemical mechanisms of inflammation and cancer. It can inhibit the activity of enzymes called lipoxygenases and cyclooxygenases, which are involved in the production of inflammatory mediators such as prostaglandins and leukotrienes. ETYA can also induce the formation of reactive oxygen species, which can contribute to cell damage and death.

While ETYA has been used in research to better understand the biochemical pathways involved in inflammation and cancer, it is not used as a therapeutic agent in clinical medicine due to its potential toxicity and lack of specificity for targeting disease processes.

Gamma-glutamyltransferase (GGT), also known as gamma-glutamyl transpeptidase, is an enzyme found in many tissues, including the liver, bile ducts, and pancreas. GGT is involved in the metabolism of certain amino acids and plays a role in the detoxification of various substances in the body.

GGT is often measured as a part of a panel of tests used to evaluate liver function. Elevated levels of GGT in the blood may indicate liver disease or injury, bile duct obstruction, or alcohol consumption. However, it's important to note that several other factors can also affect GGT levels, so abnormal results should be interpreted in conjunction with other clinical findings and diagnostic tests.

Prostaglandins are naturally occurring, lipid-derived hormones that play various important roles in the human body. They are produced in nearly every tissue in response to injury or infection, and they have diverse effects depending on the site of release and the type of prostaglandin. Some of their functions include:

1. Regulation of inflammation: Prostaglandins contribute to the inflammatory response by increasing vasodilation, promoting fluid accumulation, and sensitizing pain receptors, which can lead to symptoms such as redness, heat, swelling, and pain.
2. Modulation of gastrointestinal functions: Prostaglandins protect the stomach lining from acid secretion and promote mucus production, maintaining the integrity of the gastric mucosa. They also regulate intestinal motility and secretion.
3. Control of renal function: Prostaglandins help regulate blood flow to the kidneys, maintain sodium balance, and control renin release, which affects blood pressure and fluid balance.
4. Regulation of smooth muscle contraction: Prostaglandins can cause both relaxation and contraction of smooth muscles in various tissues, such as the uterus, bronchioles, and vascular system.
5. Modulation of platelet aggregation: Some prostaglandins inhibit platelet aggregation, preventing blood clots from forming too quickly or becoming too large.
6. Reproductive system regulation: Prostaglandins are involved in the menstrual cycle, ovulation, and labor induction by promoting uterine contractions.
7. Neurotransmission: Prostaglandins can modulate neurotransmitter release and neuronal excitability, affecting pain perception, mood, and cognition.

Prostaglandins exert their effects through specific G protein-coupled receptors (GPCRs) found on the surface of target cells. There are several distinct types of prostaglandins (PGs), including PGD2, PGE2, PGF2α, PGI2 (prostacyclin), and thromboxane A2 (TXA2). Each type has unique functions and acts through specific receptors. Prostaglandins are synthesized from arachidonic acid, a polyunsaturated fatty acid derived from membrane phospholipids, by the action of cyclooxygenase (COX) enzymes. Nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin and ibuprofen, inhibit COX activity, reducing prostaglandin synthesis and providing analgesic, anti-inflammatory, and antipyretic effects.

Chemotactic factors are substances that attract and guide cells, particularly immune cells, to specific locations in the body. Eosinophils are a type of white blood cell that play a role in the immune response, particularly against parasites and in allergic reactions. Therefore, chemotactic factors for eosinophils are substances that attract eosinophils to specific sites in the body.

These factors can be produced by various cells, including mast cells, basophils, and T-lymphocytes, in response to an infection or inflammation. They work by binding to receptors on the surface of eosinophils and activating signaling pathways that cause the eosinophils to migrate towards the source of the chemotactic factor.

Examples of chemotactic factors for eosinophils include:

1. Eotaxins: These are a group of chemokines (a type of signaling protein) that specifically attract eosinophils. They are produced by various cells, including endothelial cells, epithelial cells, and immune cells.
2. Leukotrienes: These are lipid mediators produced by mast cells and basophils in response to an allergic reaction or infection. They can attract eosinophils to the site of inflammation.
3. Platelet-activating factor (PAF): This is a lipid mediator produced by various cells, including endothelial cells and immune cells. It can attract eosinophils and activate them, leading to degranulation and release of their contents.
4. Complement components: The complement system is a group of proteins that play a role in the immune response. Some complement components, such as C3a and C5a, can act as chemotactic factors for eosinophils.

Overall, chemotactic factors for eosinophils play an important role in the immune response by recruiting these cells to sites of infection or inflammation. However, excessive activation of eosinophils and production of chemotactic factors can contribute to the development of various diseases, such as asthma and allergies.

Airway resistance is a measure of the opposition to airflow during breathing, which is caused by the friction between the air and the walls of the respiratory tract. It is an important parameter in respiratory physiology because it can affect the work of breathing and gas exchange.

Airway resistance is usually expressed in units of cm H2O/L/s or Pa·s/m, and it can be measured during spontaneous breathing or during forced expiratory maneuvers, such as those used in pulmonary function testing. Increased airway resistance can result from a variety of conditions, including asthma, chronic obstructive pulmonary disease (COPD), bronchitis, and bronchiectasis. Decreased airway resistance can be seen in conditions such as emphysema or after a successful bronchodilator treatment.

Arachidonate 15-lipoxygenase is an enzyme that catalyzes the conversion of arachidonic acid to 15-hydroperoxyeicosatetraenoic acid (15-HPETE). This enzyme plays a role in the metabolism of arachidonic acid, which is a polyunsaturated fatty acid that is released from membrane phospholipids and is a precursor for eicosanoids, which are signaling molecules that play a role in inflammation and other physiological processes.

15-lipoxygenase is one of several lipoxygenases that are found in various tissues throughout the body. These enzymes are involved in the production of leukotrienes, which are signaling molecules that play a role in inflammation and allergic responses. 15-lipoxygenase has also been implicated in the development and progression of certain diseases, including cancer and cardiovascular disease.

Inhibitors of 15-lipoxygenase have been investigated as potential therapeutic agents for the treatment of various inflammatory conditions. However, more research is needed to fully understand the role of this enzyme in health and disease and to determine the safety and efficacy of inhibiting its activity.

Exudates and transudates are two types of bodily fluids that can accumulate in various body cavities or tissues as a result of injury, inflammation, or other medical conditions. Here are the medical definitions:

1. Exudates: These are fluids that accumulate due to an active inflammatory process. Exudates contain high levels of protein, white blood cells (such as neutrophils and macrophages), and sometimes other cells like red blood cells or cellular debris. They can be yellow, green, or brown in color and may have a foul odor due to the presence of dead cells and bacteria. Exudates are often seen in conditions such as abscesses, pneumonia, pleurisy, or wound infections.

Examples of exudative fluids include pus, purulent discharge, or inflammatory effusions.

2. Transudates: These are fluids that accumulate due to increased hydrostatic pressure or decreased oncotic pressure within the blood vessels. Transudates contain low levels of protein and cells compared to exudates. They are typically clear and pale yellow in color, with no odor. Transudates can be found in conditions such as congestive heart failure, liver cirrhosis, or nephrotic syndrome.

Examples of transudative fluids include ascites, pleural effusions, or pericardial effusions.

It is essential to differentiate between exudates and transudates because their underlying causes and treatment approaches may differ significantly. Medical professionals often use various tests, such as fluid analysis, to determine whether a fluid sample is an exudate or transudate.

Formyl peptide receptors (FPRs) are a type of G protein-coupled receptors that play a crucial role in the innate immune system. They are expressed on various cells including neutrophils, monocytes, and macrophages. FPRs recognize and respond to formylated peptides derived from bacteria, mitochondria, and host proteins during cell damage or stress. Activation of FPRs triggers a variety of cellular responses, such as chemotaxis, phagocytosis, and release of inflammatory mediators, which help to eliminate invading pathogens and promote tissue repair. There are three subtypes of human FPRs (FPR1, FPR2, and FPR3) that have distinct ligand specificities and functions in the immune response.

Inflammation mediators are substances that are released by the body in response to injury or infection, which contribute to the inflammatory response. These mediators include various chemical factors such as cytokines, chemokines, prostaglandins, leukotrienes, and histamine, among others. They play a crucial role in regulating the inflammatory process by attracting immune cells to the site of injury or infection, increasing blood flow to the area, and promoting the repair and healing of damaged tissues. However, an overactive or chronic inflammatory response can also contribute to the development of various diseases and conditions, such as autoimmune disorders, cardiovascular disease, and cancer.

Radioimmunoassay (RIA) is a highly sensitive analytical technique used in clinical and research laboratories to measure concentrations of various substances, such as hormones, vitamins, drugs, or tumor markers, in biological samples like blood, urine, or tissues. The method relies on the specific interaction between an antibody and its corresponding antigen, combined with the use of radioisotopes to quantify the amount of bound antigen.

In a typical RIA procedure, a known quantity of a radiolabeled antigen (also called tracer) is added to a sample containing an unknown concentration of the same unlabeled antigen. The mixture is then incubated with a specific antibody that binds to the antigen. During the incubation period, the antibody forms complexes with both the radiolabeled and unlabeled antigens.

After the incubation, the unbound (free) radiolabeled antigen is separated from the antibody-antigen complexes, usually through a precipitation or separation step involving centrifugation, filtration, or chromatography. The amount of radioactivity in the pellet (containing the antibody-antigen complexes) is then measured using a gamma counter or other suitable radiation detection device.

The concentration of the unlabeled antigen in the sample can be determined by comparing the ratio of bound to free radiolabeled antigen in the sample to a standard curve generated from known concentrations of unlabeled antigen and their corresponding bound/free ratios. The higher the concentration of unlabeled antigen in the sample, the lower the amount of radiolabeled antigen that will bind to the antibody, resulting in a lower bound/free ratio.

Radioimmunoassays offer high sensitivity, specificity, and accuracy, making them valuable tools for detecting and quantifying low levels of various substances in biological samples. However, due to concerns about radiation safety and waste disposal, alternative non-isotopic immunoassay techniques like enzyme-linked immunosorbent assays (ELISAs) have become more popular in recent years.

Acute basophilic leukemia (ABL) is a rare and aggressive subtype of acute myeloid leukemia (AML), a type of cancer that affects the blood and bone marrow. In ABL, the malignancy originates from the transformation of hematopoietic stem cells into abnormal blast cells, specifically basophils, in the bone marrow. These blasts proliferate rapidly and disrupt normal blood cell production, leading to a significant decrease in functional red and white blood cells and platelets.

The medical definition of acute basophilic leukemia is:

A malignant neoplasm of hematopoietic stem cells characterized by the uncontrolled proliferation and accumulation of immature basophils (basophilic blasts) in the bone marrow, blood, and occasionally other tissues. This rapidly progressing disorder is accompanied by a decline in the production of normal blood cells, resulting in symptoms such as anemia, fatigue, infection, easy bruising, and bleeding. The diagnosis of ABL typically involves bone marrow aspiration and biopsy, cytogenetic analysis, immunophenotyping, and molecular genetic testing to confirm the presence of leukemic blasts and identify specific genetic abnormalities that can inform prognosis and treatment decisions.

Anti-allergic agents, also known as antihistamines, are a class of medications used to treat allergies. They work by blocking the action of histamine, a substance in the body that is released during an allergic reaction and causes symptoms such as itching, sneezing, runny nose, and watery eyes.

There are two main types of antihistamines: first-generation and second-generation. First-generation antihistamines, such as diphenhydramine (Benadryl) and chlorpheniramine (Chlor-Trimeton), can cause drowsiness and other side effects, such as dry mouth and blurred vision. They are typically used for the treatment of short-term symptoms, such as those caused by seasonal allergies or a mild reaction to an insect bite.

Second-generation antihistamines, such as loratadine (Claritin) and cetirizine (Zyrtec), are less likely to cause drowsiness and other side effects. They are often used for the long-term treatment of chronic allergies, such as those caused by dust mites or pet dander.

In addition to their use in treating allergies, antihistamines may also be used to treat symptoms of motion sickness, insomnia, and anxiety. It is important to follow the instructions on the label when taking antihistamines and to talk to a healthcare provider if you have any questions or concerns about using these medications.

Tritium is not a medical term, but it is a term used in the field of nuclear physics and chemistry. Tritium (symbol: T or 3H) is a radioactive isotope of hydrogen with two neutrons and one proton in its nucleus. It is also known as heavy hydrogen or superheavy hydrogen.

Tritium has a half-life of about 12.3 years, which means that it decays by emitting a low-energy beta particle (an electron) to become helium-3. Due to its radioactive nature and relatively short half-life, tritium is used in various applications, including nuclear weapons, fusion reactors, luminous paints, and medical research.

In the context of medicine, tritium may be used as a radioactive tracer in some scientific studies or medical research, but it is not a term commonly used to describe a medical condition or treatment.

Exercise-induced asthma (EIA) is a type of asthma that is triggered by physical activity or exercise. Officially known as exercise-induced bronchoconstriction (EIB), this condition causes the airways in the lungs to narrow and become inflamed, leading to symptoms such as wheezing, coughing, shortness of breath, and chest tightness. These symptoms typically occur during or after exercise and can last for several minutes to a few hours.

EIA is caused by the loss of heat and moisture from the airways during exercise, which leads to the release of inflammatory mediators that cause the airways to constrict. People with EIA may have underlying asthma or may only experience symptoms during exercise. Proper diagnosis and management of EIA can help individuals maintain an active lifestyle and participate in physical activities without experiencing symptoms.

Bronchial provocation tests are a group of medical tests used to assess the airway responsiveness of the lungs by challenging them with increasing doses of a specific stimulus, such as methacholine or histamine, which can cause bronchoconstriction (narrowing of the airways) in susceptible individuals. These tests are often performed to diagnose and monitor asthma and other respiratory conditions that may be associated with heightened airway responsiveness.

The most common type of bronchial provocation test is the methacholine challenge test, which involves inhaling increasing concentrations of methacholine aerosol via a nebulizer. The dose response is measured by monitoring lung function (usually through spirometry) before and after each exposure. A positive test is indicated when there is a significant decrease in forced expiratory volume in one second (FEV1) or other measures of airflow, which suggests bronchial hyperresponsiveness.

Other types of bronchial provocation tests include histamine challenges, exercise challenges, and mannitol challenges. These tests have specific indications, contraindications, and protocols that should be followed to ensure accurate results and patient safety. Bronchial provocation tests are typically conducted in a controlled clinical setting under the supervision of trained healthcare professionals.

A cell line is a culture of cells that are grown in a laboratory for use in research. These cells are usually taken from a single cell or group of cells, and they are able to divide and grow continuously in the lab. Cell lines can come from many different sources, including animals, plants, and humans. They are often used in scientific research to study cellular processes, disease mechanisms, and to test new drugs or treatments. Some common types of human cell lines include HeLa cells (which come from a cancer patient named Henrietta Lacks), HEK293 cells (which come from embryonic kidney cells), and HUVEC cells (which come from umbilical vein endothelial cells). It is important to note that cell lines are not the same as primary cells, which are cells that are taken directly from a living organism and have not been grown in the lab.

Eicosanoid receptors are a type of cell surface receptor that bind and respond to signaling molecules called eicosanoids. These receptors play a crucial role in various physiological processes, including inflammation, immune response, blood clotting, and the regulation of blood pressure and flow.

Eicosanoids are derived from the metabolism of arachidonic acid and other polyunsaturated fatty acids with 20 carbon atoms (hence "eicosa" in eicosanoid). They include prostaglandins, thromboxanes, leukotrienes, and lipoxins.

Eicosanoid receptors are found on various cell types throughout the body, including immune cells, endothelial cells, smooth muscle cells, and neurons. When an eicosanoid binds to its specific receptor, it triggers a cascade of intracellular signaling events that ultimately lead to changes in gene expression, cell behavior, or both.

There are several families of eicosanoid receptors, including prostaglandin receptors, thromboxane receptors, leukotriene receptors, and lipoxin receptors. Each family contains multiple subtypes with distinct pharmacological properties and physiological functions.

Understanding the role of eicosanoid receptors in health and disease has important implications for drug development and the treatment of various medical conditions, such as inflammation, pain, asthma, cardiovascular diseases, and cancer.

"Inbred strains of rats" are genetically identical rodents that have been produced through many generations of brother-sister mating. This results in a high degree of homozygosity, where the genes at any particular locus in the genome are identical in all members of the strain.

Inbred strains of rats are widely used in biomedical research because they provide a consistent and reproducible genetic background for studying various biological phenomena, including the effects of drugs, environmental factors, and genetic mutations on health and disease. Additionally, inbred strains can be used to create genetically modified models of human diseases by introducing specific mutations into their genomes.

Some commonly used inbred strains of rats include the Wistar Kyoto (WKY), Sprague-Dawley (SD), and Fischer 344 (F344) rat strains. Each strain has its own unique genetic characteristics, making them suitable for different types of research.

The peritoneal cavity is the potential space within the abdominal and pelvic regions, bounded by the parietal peritoneum lining the inner aspect of the abdominal and pelvic walls, and the visceral peritoneum covering the abdominal and pelvic organs. It contains a small amount of serous fluid that allows for the gliding of organs against each other during normal physiological activities such as digestion and movement. This cavity can become pathologically involved in various conditions, including inflammation, infection, hemorrhage, or neoplasia, leading to symptoms like abdominal pain, distention, or tenderness.

Lipoxins are a group of anti-inflammatory mediators that play a role in the resolution of inflammation. They are produced from arachidonic acid, a type of omega-6 fatty acid, through the action of lipoxygenase enzymes. There are several types of lipoxin receptors (ALX/FPR2 and GPR31) that have been identified, which belong to the family of G protein-coupled receptors. These receptors are expressed in various tissues, including the cardiovascular, respiratory, and gastrointestinal systems. Activation of lipoxin receptors leads to a variety of cellular responses, such as inhibition of inflammatory cytokine production, reduction of oxidative stress, and promotion of tissue repair. Dysregulation of the lipoxin signaling pathway has been implicated in several diseases, including asthma, atherosclerosis, and cancer.

Group V Phospholipases A2 (Group V PLA2s) are a subclass of the phospholipase A2 enzymes, which are a group of enzymes that hydrolyze the sn-2 ester bond of glycerophospholipids to release free fatty acids and lysophospholipids. Specifically, Group V PLA2s are calcium-dependent cytosolic enzymes that play a role in inflammation, immunity, and cell signaling processes.

Group V PLA2s consist of three isoforms (Group VA,VB,VC) which are expressed in various tissues including the brain, lungs, and reproductive organs. They have been implicated in several pathological conditions such as atherosclerosis, acute respiratory distress syndrome (ARDS), and cancer.

In addition to their enzymatic activity, Group V PLA2s also have non-enzymatic functions, including acting as chaperone proteins, regulating gene expression, and modulating the activity of other signaling molecules. Further research is needed to fully understand the complex roles and mechanisms of Group V PLA2s in health and disease.

Mass spectrometry (MS) is an analytical technique used to identify and quantify the chemical components of a mixture or compound. It works by ionizing the sample, generating charged molecules or fragments, and then measuring their mass-to-charge ratio in a vacuum. The resulting mass spectrum provides information about the molecular weight and structure of the analytes, allowing for identification and characterization.

In simpler terms, mass spectrometry is a method used to determine what chemicals are present in a sample and in what quantities, by converting the chemicals into ions, measuring their masses, and generating a spectrum that shows the relative abundances of each ion type.

Anaphylaxis is a severe, life-threatening systemic allergic reaction that occurs suddenly after exposure to an allergen (a substance that triggers an allergic reaction) to which the person has previously been sensitized. The symptoms of anaphylaxis include rapid onset of symptoms such as itching, hives, swelling of the throat and tongue, difficulty breathing, wheezing, cough, chest tightness, rapid heartbeat, hypotension (low blood pressure), shock, and in severe cases, loss of consciousness and death. Anaphylaxis is a medical emergency that requires immediate treatment with epinephrine (adrenaline) and other supportive measures to stabilize the patient's condition.

Neutrophil activation refers to the process by which neutrophils, a type of white blood cell, become activated in response to a signal or stimulus, such as an infection or inflammation. This activation triggers a series of responses within the neutrophil that enable it to carry out its immune functions, including:

1. Degranulation: The release of granules containing enzymes and other proteins that can destroy microbes.
2. Phagocytosis: The engulfment and destruction of microbes through the use of reactive oxygen species (ROS) and other toxic substances.
3. Formation of neutrophil extracellular traps (NETs): A process in which neutrophils release DNA and proteins to trap and kill microbes outside the cell.
4. Release of cytokines and chemokines: Signaling molecules that recruit other immune cells to the site of infection or inflammation.

Neutrophil activation is a critical component of the innate immune response, but excessive or uncontrolled activation can contribute to tissue damage and chronic inflammation.

Glutathione is a tripeptide composed of three amino acids: cysteine, glutamic acid, and glycine. It is a vital antioxidant that plays an essential role in maintaining cellular health and function. Glutathione helps protect cells from oxidative stress by neutralizing free radicals, which are unstable molecules that can damage cells and contribute to aging and diseases such as cancer, heart disease, and dementia. It also supports the immune system, detoxifies harmful substances, and regulates various cellular processes, including DNA synthesis and repair.

Glutathione is found in every cell of the body, with particularly high concentrations in the liver, lungs, and eyes. The body can produce its own glutathione, but levels may decline with age, illness, or exposure to toxins. As such, maintaining optimal glutathione levels through diet, supplementation, or other means is essential for overall health and well-being.

Prostaglandin-Endoperoxide Synthases (PTGS), also known as Cyclooxygenases (COX), are a group of enzymes that catalyze the conversion of arachidonic acid into prostaglandin G2 and H2, which are further metabolized to produce various prostaglandins and thromboxanes. These lipid mediators play crucial roles in several physiological processes such as inflammation, pain, fever, and blood clotting. There are two major isoforms of PTGS: PTGS-1 (COX-1) and PTGS-2 (COX-2). While COX-1 is constitutively expressed in most tissues and involved in homeostatic functions, COX-2 is usually induced during inflammation and tissue injury. Nonsteroidal anti-inflammatory drugs (NSAIDs) exert their therapeutic effects by inhibiting these enzymes, thereby reducing the production of prostaglandins and thromboxanes.

Bronchoalveolar lavage (BAL) fluid is a type of clinical specimen obtained through a procedure called bronchoalveolar lavage. This procedure involves inserting a bronchoscope into the lungs and instilling a small amount of saline solution into a specific area of the lung, then gently aspirating the fluid back out. The fluid that is recovered is called bronchoalveolar lavage fluid.

BAL fluid contains cells and other substances that are present in the lower respiratory tract, including the alveoli (the tiny air sacs where gas exchange occurs). By analyzing BAL fluid, doctors can diagnose various lung conditions, such as pneumonia, interstitial lung disease, and lung cancer. They can also monitor the effectiveness of treatments for these conditions by comparing the composition of BAL fluid before and after treatment.

BAL fluid is typically analyzed for its cellular content, including the number and type of white blood cells present, as well as for the presence of bacteria, viruses, or other microorganisms. The fluid may also be tested for various proteins, enzymes, and other biomarkers that can provide additional information about lung health and disease.

Borates are a group of minerals that contain boron, oxygen, and hydrogen in various combinations. They can also contain other elements such as sodium, calcium, or potassium. Borates have a wide range of uses, including as flame retardants, insecticides, and preservatives. In medicine, boric acid powder is sometimes used as a mild antiseptic to treat minor cuts, burns, and scrapes. However, it can be toxic if ingested or absorbed through the skin in large amounts, so it should be used with caution.

Alveolar macrophages are a type of macrophage (a large phagocytic cell) that are found in the alveoli of the lungs. They play a crucial role in the immune defense system of the lungs by engulfing and destroying any foreign particles, such as dust, microorganisms, and pathogens, that enter the lungs through the process of inhalation. Alveolar macrophages also produce cytokines, which are signaling molecules that help to coordinate the immune response. They are important for maintaining the health and function of the lungs by removing debris and preventing infection.

Catechols are a type of chemical compound that contain a benzene ring with two hydroxyl groups (-OH) attached to it in the ortho position. The term "catechol" is often used interchangeably with "ortho-dihydroxybenzene." Catechols are important in biology because they are produced through the metabolism of certain amino acids, such as phenylalanine and tyrosine, and are involved in the synthesis of various neurotransmitters and hormones. They also have antioxidant properties and can act as reducing agents. In chemistry, catechols can undergo various reactions, such as oxidation and polymerization, to form other classes of compounds.

Sneezing is an involuntary, forceful expulsion of air through the nose and mouth, often triggered by irritation or inflammation in the nasal passages. It is a protective reflex that helps to clear the upper respiratory tract of irritants such as dust, pollen, or foreign particles. The sneeze begins with a deep inspiration of air, followed by closure of the glottis (the opening between the vocal cords) and contraction of the chest and abdominal muscles. This builds up pressure in the lungs, which is then suddenly released through the nose and mouth as the glottis opens and the velum (the soft tissue at the back of the roof of the mouth) rises to block the nasal passage. The result is a powerful burst of air that can travel at speeds of up to 100 miles per hour, expelling mucus and any trapped irritants along with it.

In the field of medicine, "time factors" refer to the duration of symptoms or time elapsed since the onset of a medical condition, which can have significant implications for diagnosis and treatment. Understanding time factors is crucial in determining the progression of a disease, evaluating the effectiveness of treatments, and making critical decisions regarding patient care.

For example, in stroke management, "time is brain," meaning that rapid intervention within a specific time frame (usually within 4.5 hours) is essential to administering tissue plasminogen activator (tPA), a clot-busting drug that can minimize brain damage and improve patient outcomes. Similarly, in trauma care, the "golden hour" concept emphasizes the importance of providing definitive care within the first 60 minutes after injury to increase survival rates and reduce morbidity.

Time factors also play a role in monitoring the progression of chronic conditions like diabetes or heart disease, where regular follow-ups and assessments help determine appropriate treatment adjustments and prevent complications. In infectious diseases, time factors are crucial for initiating antibiotic therapy and identifying potential outbreaks to control their spread.

Overall, "time factors" encompass the significance of recognizing and acting promptly in various medical scenarios to optimize patient outcomes and provide effective care.

Prostaglandin E (PGE) is a type of prostaglandin, which is a group of lipid compounds that are synthesized in the body from fatty acids and have diverse hormone-like effects. Prostaglandins are not actually hormones, but are similar to them in that they act as chemical messengers that have specific effects on certain cells.

Prostaglandin E is one of the most abundant prostaglandins in the body and has a variety of physiological functions. It is involved in the regulation of inflammation, pain perception, fever, and smooth muscle contraction. Prostaglandin E also plays a role in the regulation of blood flow, platelet aggregation, and gastric acid secretion.

Prostaglandin E is synthesized from arachidonic acid, which is released from cell membranes by the action of enzymes called phospholipases. Once formed, prostaglandin E binds to specific receptors on the surface of cells, leading to a variety of intracellular signaling events that ultimately result in changes in cell behavior.

Prostaglandin E is used medically in the treatment of several conditions, including dysmenorrhea (painful menstruation), postpartum hemorrhage, and patent ductus arteriosus (a congenital heart defect). It is also used as a diagnostic tool in the evaluation of kidney function.

Recombinant proteins are artificially created proteins produced through the use of recombinant DNA technology. This process involves combining DNA molecules from different sources to create a new set of genes that encode for a specific protein. The resulting recombinant protein can then be expressed, purified, and used for various applications in research, medicine, and industry.

Recombinant proteins are widely used in biomedical research to study protein function, structure, and interactions. They are also used in the development of diagnostic tests, vaccines, and therapeutic drugs. For example, recombinant insulin is a common treatment for diabetes, while recombinant human growth hormone is used to treat growth disorders.

The production of recombinant proteins typically involves the use of host cells, such as bacteria, yeast, or mammalian cells, which are engineered to express the desired protein. The host cells are transformed with a plasmid vector containing the gene of interest, along with regulatory elements that control its expression. Once the host cells are cultured and the protein is expressed, it can be purified using various chromatography techniques.

Overall, recombinant proteins have revolutionized many areas of biology and medicine, enabling researchers to study and manipulate proteins in ways that were previously impossible.

Molecular sequence data refers to the specific arrangement of molecules, most commonly nucleotides in DNA or RNA, or amino acids in proteins, that make up a biological macromolecule. This data is generated through laboratory techniques such as sequencing, and provides information about the exact order of the constituent molecules. This data is crucial in various fields of biology, including genetics, evolution, and molecular biology, allowing for comparisons between different organisms, identification of genetic variations, and studies of gene function and regulation.

Non-steroidal anti-inflammatory agents (NSAIDs) are a class of medications that reduce pain, inflammation, and fever. They work by inhibiting the activity of cyclooxygenase (COX) enzymes, which are involved in the production of prostaglandins, chemicals that contribute to inflammation and cause blood vessels to dilate and become more permeable, leading to symptoms such as pain, redness, warmth, and swelling.

NSAIDs are commonly used to treat a variety of conditions, including arthritis, muscle strains and sprains, menstrual cramps, headaches, and fever. Some examples of NSAIDs include aspirin, ibuprofen, naproxen, and celecoxib.

While NSAIDs are generally safe and effective when used as directed, they can have side effects, particularly when taken in large doses or for long periods of time. Common side effects include stomach ulcers, gastrointestinal bleeding, and increased risk of heart attack and stroke. It is important to follow the recommended dosage and consult with a healthcare provider if you have any concerns about using NSAIDs.

An "injection, intradermal" refers to a type of injection where a small quantity of a substance is introduced into the layer of skin between the epidermis and dermis, using a thin gauge needle. This technique is often used for diagnostic or research purposes, such as conducting allergy tests or administering immunizations in a way that stimulates a strong immune response. The injection site typically produces a small, raised bump (wheal) that disappears within a few hours. It's important to note that intradermal injections should be performed by trained medical professionals to minimize the risk of complications.

Neutrophil infiltration is a pathological process characterized by the accumulation of neutrophils, a type of white blood cell, in tissue. It is a common feature of inflammation and occurs in response to infection, injury, or other stimuli that trigger an immune response. Neutrophils are attracted to the site of tissue damage by chemical signals called chemokines, which are released by damaged cells and activated immune cells. Once they reach the site of inflammation, neutrophils help to clear away damaged tissue and microorganisms through a process called phagocytosis. However, excessive or prolonged neutrophil infiltration can also contribute to tissue damage and may be associated with various disease states, including cancer, autoimmune disorders, and ischemia-reperfusion injury.

Thromboxanes are a type of lipid compound that is derived from arachidonic acid, a type of fatty acid found in the cell membranes of many organisms. They are synthesized in the body through the action of an enzyme called cyclooxygenase (COX).

Thromboxanes are primarily produced by platelets, a type of blood cell that plays a key role in clotting. Once formed, thromboxanes act as powerful vasoconstrictors, causing blood vessels to narrow and blood flow to decrease. They also promote the aggregation of platelets, which can lead to the formation of blood clots.

Thromboxanes are involved in many physiological processes, including hemostasis (the process by which bleeding is stopped) and inflammation. However, excessive production of thromboxanes has been implicated in a number of pathological conditions, such as heart attacks, strokes, and pulmonary hypertension.

There are several different types of thromboxanes, including thromboxane A2 (TXA2) and thromboxane B2 (TXB2). TXA2 is the most biologically active form and has a very short half-life, while TXB2 is a more stable metabolite that can be measured in the blood to assess thromboxane production.

5-Lipoxygenase-activating protein inhibitors (FLAP inhibitors) are a class of drugs that work by blocking the activity of 5-lipoxygenase-activating protein (FLAP), an enzyme that plays a crucial role in the biosynthesis of leukotrienes. Leukotrienes are inflammatory mediators that contribute to the development of various respiratory and allergic diseases, such as asthma, rhinitis, and chronic obstructive pulmonary disease (COPD).

By inhibiting FLAP, these drugs prevent the formation of leukotrienes, thereby reducing inflammation and airway hyperresponsiveness. Examples of FLAP inhibitors include MK-0886, CDC-H5247, and BAYx1005. These drugs have shown promise in preclinical and early clinical studies, but further research is needed to establish their safety and efficacy in larger patient populations.

Diynes are organic compounds that contain two carbon-carbon triple bonds in their molecular structure. The general chemical formula for diynes is R-C≡C-C≡C-R, where R can be a hydrogen atom or any organic group. Diynes are important building blocks in organic synthesis and have been used to create complex molecules, nanomaterials, and pharmaceuticals. They are also of interest in materials science due to their unique electronic properties and potential applications in optoelectronics and photonics.

Microsomes are subcellular membranous vesicles that are obtained as a byproduct during the preparation of cellular homogenates. They are not naturally occurring structures within the cell, but rather formed due to fragmentation of the endoplasmic reticulum (ER) during laboratory procedures. Microsomes are widely used in various research and scientific studies, particularly in the fields of biochemistry and pharmacology.

Microsomes are rich in enzymes, including the cytochrome P450 system, which is involved in the metabolism of drugs, toxins, and other xenobiotics. These enzymes play a crucial role in detoxifying foreign substances and eliminating them from the body. As such, microsomes serve as an essential tool for studying drug metabolism, toxicity, and interactions, allowing researchers to better understand and predict the effects of various compounds on living organisms.

Cell degranulation is the process by which cells, particularly immune cells like mast cells and basophils, release granules containing inflammatory mediators in response to various stimuli. These mediators include histamine, leukotrienes, prostaglandins, and other chemicals that play a role in allergic reactions, inflammation, and immune responses. The activation of cell surface receptors triggers a signaling cascade that leads to the exocytosis of these granules, resulting in degranulation. This process is important for the immune system's response to foreign invaders and for the development of allergic reactions.

Immunologic receptors are specialized proteins found on the surface of immune cells that recognize and bind to specific molecules, known as antigens, on the surface of pathogens or infected cells. This binding triggers a series of intracellular signaling events that activate the immune cell and initiate an immune response.

There are several types of immunologic receptors, including:

1. T-cell receptors (TCRs): These receptors are found on the surface of T cells and recognize antigens presented in the context of major histocompatibility complex (MHC) molecules.
2. B-cell receptors (BCRs): These receptors are found on the surface of B cells and recognize free antigens in solution.
3. Pattern recognition receptors (PRRs): These receptors are found inside immune cells and recognize conserved molecular patterns associated with pathogens, such as lipopolysaccharides and flagellin.
4. Fc receptors: These receptors are found on the surface of various immune cells and bind to the constant region of antibodies, mediating effector functions such as phagocytosis and antibody-dependent cellular cytotoxicity (ADCC).

Immunologic receptors play a critical role in the recognition and elimination of pathogens and infected cells, and dysregulation of these receptors can lead to immune disorders and diseases.

Signal transduction is the process by which a cell converts an extracellular signal, such as a hormone or neurotransmitter, into an intracellular response. This involves a series of molecular events that transmit the signal from the cell surface to the interior of the cell, ultimately resulting in changes in gene expression, protein activity, or metabolism.

The process typically begins with the binding of the extracellular signal to a receptor located on the cell membrane. This binding event activates the receptor, which then triggers a cascade of intracellular signaling molecules, such as second messengers, protein kinases, and ion channels. These molecules amplify and propagate the signal, ultimately leading to the activation or inhibition of specific cellular responses.

Signal transduction pathways are highly regulated and can be modulated by various factors, including other signaling molecules, post-translational modifications, and feedback mechanisms. Dysregulation of these pathways has been implicated in a variety of diseases, including cancer, diabetes, and neurological disorders.

Enzyme inhibitors are substances that bind to an enzyme and decrease its activity, preventing it from catalyzing a chemical reaction in the body. They can work by several mechanisms, including blocking the active site where the substrate binds, or binding to another site on the enzyme to change its shape and prevent substrate binding. Enzyme inhibitors are often used as drugs to treat various medical conditions, such as high blood pressure, abnormal heart rhythms, and bacterial infections. They can also be found naturally in some foods and plants, and can be used in research to understand enzyme function and regulation.

Allergic rhinitis, seasonal (also known as hay fever) is a type of inflammation in the nose which occurs when an individual breathes in allergens such as pollen or mold spores. The immune system identifies these substances as harmful and releases histamine and other chemicals, causing symptoms such as sneezing, runny or stuffy nose, red, watery, and itchy eyes, cough, and fatigue. Unlike perennial allergic rhinitis, seasonal allergic rhinitis is worse during specific times of the year when certain plants pollinate.

An amino acid sequence is the specific order of amino acids in a protein or peptide molecule, formed by the linking of the amino group (-NH2) of one amino acid to the carboxyl group (-COOH) of another amino acid through a peptide bond. The sequence is determined by the genetic code and is unique to each type of protein or peptide. It plays a crucial role in determining the three-dimensional structure and function of proteins.

Forced Expiratory Volume (FEV) is a medical term used to describe the volume of air that can be forcefully exhaled from the lungs in one second. It is often measured during pulmonary function testing to assess lung function and diagnose conditions such as chronic obstructive pulmonary disease (COPD) or asthma.

FEV is typically expressed as a percentage of the Forced Vital Capacity (FVC), which is the total volume of air that can be exhaled from the lungs after taking a deep breath in. The ratio of FEV to FVC is used to determine whether there is obstruction in the airways, with a lower ratio indicating more severe obstruction.

There are different types of FEV measurements, including FEV1 (the volume of air exhaled in one second), FEV25-75 (the average volume of air exhaled during the middle 50% of the FVC maneuver), and FEV0.5 (the volume of air exhaled in half a second). These measurements can provide additional information about lung function and help guide treatment decisions.

Pruritus is a medical term derived from Latin, in which "prurire" means "to itch." It refers to an unpleasant sensation on the skin that provokes the desire or reflex to scratch. This can be caused by various factors, such as skin conditions (e.g., dryness, eczema, psoriasis), systemic diseases (e.g., liver disease, kidney failure), nerve disorders, psychological conditions, or reactions to certain medications.

Pruritus can significantly affect a person's quality of life, leading to sleep disturbances, anxiety, and depression. Proper identification and management of the underlying cause are essential for effective treatment.

Prostaglandin H2 (PGH2) is not a medical condition, but rather a chemical compound that acts as a precursor in the synthesis of other prostaglandins and thromboxanes. It is produced from arachidonic acid by the action of the enzyme cyclooxygenase (COX). PGH2 is then converted into various downstream prostanoids, such as PGD2, PGE2, PGF2α, PGI2 (prostacyclin), and TXA2 (thromboxane A2), by specific synthases. These prostanoids have diverse biological activities, including regulation of inflammation, pain, fever, blood flow, and platelet aggregation.

Urticaria, also known as hives, is an allergic reaction that appears on the skin. It is characterized by the rapid appearance of swollen, pale red bumps or plaques (wheals) on the skin, which are often accompanied by itching, stinging, or burning sensations. These wheals can vary in size and shape, and they may change location and appear in different places over a period of hours or days. Urticaria is usually caused by an allergic reaction to food, medication, or other substances, but it can also be triggered by physical factors such as heat, cold, pressure, or exercise. The condition is generally harmless, but severe cases of urticaria may indicate a more serious underlying medical issue and should be evaluated by a healthcare professional.

Macrophages are a type of white blood cell that are an essential part of the immune system. They are large, specialized cells that engulf and destroy foreign substances, such as bacteria, viruses, parasites, and fungi, as well as damaged or dead cells. Macrophages are found throughout the body, including in the bloodstream, lymph nodes, spleen, liver, lungs, and connective tissues. They play a critical role in inflammation, immune response, and tissue repair and remodeling.

Macrophages originate from monocytes, which are a type of white blood cell produced in the bone marrow. When monocytes enter the tissues, they differentiate into macrophages, which have a larger size and more specialized functions than monocytes. Macrophages can change their shape and move through tissues to reach sites of infection or injury. They also produce cytokines, chemokines, and other signaling molecules that help coordinate the immune response and recruit other immune cells to the site of infection or injury.

Macrophages have a variety of surface receptors that allow them to recognize and respond to different types of foreign substances and signals from other cells. They can engulf and digest foreign particles, bacteria, and viruses through a process called phagocytosis. Macrophages also play a role in presenting antigens to T cells, which are another type of immune cell that helps coordinate the immune response.

Overall, macrophages are crucial for maintaining tissue homeostasis, defending against infection, and promoting wound healing and tissue repair. Dysregulation of macrophage function has been implicated in a variety of diseases, including cancer, autoimmune disorders, and chronic inflammatory conditions.

Methacholine chloride is a medication that is used as a diagnostic tool to help identify and assess the severity of asthma or other respiratory conditions that cause airway hyperresponsiveness. It is a synthetic derivative of acetylcholine, which is a neurotransmitter that causes smooth muscle contraction in the body.

When methacholine chloride is inhaled, it stimulates the muscarinic receptors in the airways, causing them to constrict or narrow. This response is measured and used to determine the degree of airway hyperresponsiveness, which can help diagnose asthma and assess its severity.

The methacholine challenge test involves inhaling progressively higher doses of methacholine chloride until a significant decrease in lung function is observed or until a maximum dose is reached. The test results are then used to guide treatment decisions and monitor the effectiveness of therapy. It's important to note that this test should be conducted under the supervision of a healthcare professional, as it carries some risks, including bronchoconstriction and respiratory distress.

Respiratory hypersensitivity, also known as respiratory allergies or hypersensitive pneumonitis, refers to an exaggerated immune response in the lungs to inhaled substances or allergens. This condition occurs when the body's immune system overreacts to harmless particles, leading to inflammation and damage in the airways and alveoli (air sacs) of the lungs.

There are two types of respiratory hypersensitivity: immediate and delayed. Immediate hypersensitivity, also known as type I hypersensitivity, is mediated by immunoglobulin E (IgE) antibodies and results in symptoms such as sneezing, runny nose, and asthma-like symptoms within minutes to hours of exposure to the allergen. Delayed hypersensitivity, also known as type III or type IV hypersensitivity, is mediated by other immune mechanisms and can take several hours to days to develop after exposure to the allergen.

Common causes of respiratory hypersensitivity include mold spores, animal dander, dust mites, pollen, and chemicals found in certain occupations. Symptoms may include coughing, wheezing, shortness of breath, chest tightness, and fatigue. Treatment typically involves avoiding the allergen, if possible, and using medications such as corticosteroids, bronchodilators, or antihistamines to manage symptoms. In severe cases, immunotherapy (allergy shots) may be recommended to help desensitize the immune system to the allergen.

Stereoisomerism is a type of isomerism (structural arrangement of atoms) in which molecules have the same molecular formula and sequence of bonded atoms, but differ in the three-dimensional orientation of their atoms in space. This occurs when the molecule contains asymmetric carbon atoms or other rigid structures that prevent free rotation, leading to distinct spatial arrangements of groups of atoms around a central point. Stereoisomers can have different chemical and physical properties, such as optical activity, boiling points, and reactivities, due to differences in their shape and the way they interact with other molecules.

There are two main types of stereoisomerism: enantiomers (mirror-image isomers) and diastereomers (non-mirror-image isomers). Enantiomers are pairs of stereoisomers that are mirror images of each other, but cannot be superimposed on one another. Diastereomers, on the other hand, are non-mirror-image stereoisomers that have different physical and chemical properties.

Stereoisomerism is an important concept in chemistry and biology, as it can affect the biological activity of molecules, such as drugs and natural products. For example, some enantiomers of a drug may be active, while others are inactive or even toxic. Therefore, understanding stereoisomerism is crucial for designing and synthesizing effective and safe drugs.

Ovalbumin is the major protein found in egg white, making up about 54-60% of its total protein content. It is a glycoprotein with a molecular weight of around 45 kDa and has both hydrophilic and hydrophobic regions. Ovalbumin is a single polypeptide chain consisting of 385 amino acids, including four disulfide bridges that contribute to its structure.

Ovalbumin is often used in research as a model antigen for studying immune responses and allergies. In its native form, ovalbumin is not allergenic; however, when it is denatured or degraded into smaller peptides through cooking or digestion, it can become an allergen for some individuals.

In addition to being a food allergen, ovalbumin has been used in various medical and research applications, such as vaccine development, immunological studies, and protein structure-function analysis.

Anti-inflammatory agents are a class of drugs or substances that reduce inflammation in the body. They work by inhibiting the production of inflammatory mediators, such as prostaglandins and leukotrienes, which are released during an immune response and contribute to symptoms like pain, swelling, redness, and warmth.

There are two main types of anti-inflammatory agents: steroidal and nonsteroidal. Steroidal anti-inflammatory drugs (SAIDs) include corticosteroids, which mimic the effects of hormones produced by the adrenal gland. Nonsteroidal anti-inflammatory drugs (NSAIDs) are a larger group that includes both prescription and over-the-counter medications, such as aspirin, ibuprofen, naproxen, and celecoxib.

While both types of anti-inflammatory agents can be effective in reducing inflammation and relieving symptoms, they differ in their mechanisms of action, side effects, and potential risks. Long-term use of NSAIDs, for example, can increase the risk of gastrointestinal bleeding, kidney damage, and cardiovascular events. Corticosteroids can have significant side effects as well, particularly with long-term use, including weight gain, mood changes, and increased susceptibility to infections.

It's important to use anti-inflammatory agents only as directed by a healthcare provider, and to be aware of potential risks and interactions with other medications or health conditions.

Terfenadine is an antihistamine medication that has been used to treat symptoms of allergies such as hay fever, hives, and other allergic reactions. It works by blocking the action of histamine, a substance in the body that causes allergic symptoms. Terfenadine was first approved for use in the United States in 1985, but it is no longer available in many countries due to concerns about rare but serious side effects related to heart rhythm disturbances. It has been replaced by other antihistamines that are considered safer and more effective.

Thromboxane A2 (TXA2) is a potent prostanoid, a type of lipid compound derived from arachidonic acid. It is primarily produced and released by platelets upon activation during the process of hemostasis (the body's response to stop bleeding). TXA2 acts as a powerful vasoconstrictor, causing blood vessels to narrow, which helps limit blood loss at the site of injury. Additionally, it promotes platelet aggregation, contributing to the formation of a stable clot and preventing further bleeding. However, uncontrolled or excessive production of TXA2 can lead to thrombotic events such as heart attacks and strokes. Its effects are balanced by prostacyclin (PGI2), which is produced by endothelial cells and has opposing actions, acting as a vasodilator and inhibiting platelet aggregation. The balance between TXA2 and PGI2 helps maintain vascular homeostasis.

Edema is the medical term for swelling caused by excess fluid accumulation in the body tissues. It can affect any part of the body, but it's most commonly noticed in the hands, feet, ankles, and legs. Edema can be a symptom of various underlying medical conditions, such as heart failure, kidney disease, liver disease, or venous insufficiency.

The swelling occurs when the capillaries leak fluid into the surrounding tissues, causing them to become swollen and puffy. The excess fluid can also collect in the cavities of the body, leading to conditions such as pleural effusion (fluid around the lungs) or ascites (fluid in the abdominal cavity).

The severity of edema can vary from mild to severe, and it may be accompanied by other symptoms such as skin discoloration, stiffness, and pain. Treatment for edema depends on the underlying cause and may include medications, lifestyle changes, or medical procedures.

6-Ketoprostaglandin F1 alpha, also known as prostaglandin H1A, is a stable metabolite of prostaglandin F2alpha (PGF2alpha). It is a type of eicosanoid, which is a signaling molecule made by the enzymatic or non-enzymatic oxidation of arachidonic acid or other polyunsaturated fatty acids. Prostaglandins are a subclass of eicosanoids and have diverse hormone-like effects in various tissues, including smooth muscle contraction, vasodilation, and modulation of inflammation.

6-Ketoprostaglandin F1 alpha is formed by the oxidation of PGF2alpha by 15-hydroxyprostaglandin dehydrogenase (15-PGDH), an enzyme that metabolizes prostaglandins and thromboxanes. It has been used as a biomarker for the measurement of PGF2alpha production in research settings, but it does not have any known physiological activity.

Beta-N-Acetylhexosaminidases are a group of enzymes that play a role in the breakdown and recycling of complex carbohydrates in the body. Specifically, they help to break down gangliosides, which are a type of molecule found in cell membranes.

There are several different isoforms of beta-N-Acetylhexosaminidases, including A, B, and S. These isoforms are formed by different combinations of subunits, which can affect their activity and substrate specificity.

Mutations in the genes that encode for these enzymes can lead to a variety of genetic disorders, including Tay-Sachs disease and Sandhoff disease. These conditions are characterized by an accumulation of gangliosides in the brain, which can cause progressive neurological deterioration and death.

Treatment for these conditions typically involves managing symptoms and providing supportive care, as there is currently no cure. Enzyme replacement therapy has been explored as a potential treatment option, but its effectiveness varies depending on the specific disorder and the age of the patient.

The adrenal cortex hormones are a group of steroid hormones produced and released by the outer portion (cortex) of the adrenal glands, which are located on top of each kidney. These hormones play crucial roles in regulating various physiological processes, including:

1. Glucose metabolism: Cortisol helps control blood sugar levels by increasing glucose production in the liver and reducing its uptake in peripheral tissues.
2. Protein and fat metabolism: Cortisol promotes protein breakdown and fatty acid mobilization, providing essential building blocks for energy production during stressful situations.
3. Immune response regulation: Cortisol suppresses immune function to prevent overactivation and potential damage to the body during stress.
4. Cardiovascular function: Aldosterone regulates electrolyte balance and blood pressure by promoting sodium reabsorption and potassium excretion in the kidneys.
5. Sex hormone production: The adrenal cortex produces small amounts of sex hormones, such as androgens and estrogens, which contribute to sexual development and function.
6. Growth and development: Cortisol plays a role in normal growth and development by influencing the activity of growth-promoting hormones like insulin-like growth factor 1 (IGF-1).

The main adrenal cortex hormones include:

1. Glucocorticoids: Cortisol is the primary glucocorticoid, responsible for regulating metabolism and stress response.
2. Mineralocorticoids: Aldosterone is the primary mineralocorticoid, involved in electrolyte balance and blood pressure regulation.
3. Androgens: Dehydroepiandrosterone (DHEA) and its sulfate derivative (DHEAS) are the most abundant adrenal androgens, contributing to sexual development and function.
4. Estrogens: Small amounts of estrogens are produced by the adrenal cortex, mainly in women.

Disorders related to impaired adrenal cortex hormone production or regulation can lead to various clinical manifestations, such as Addison's disease (adrenal insufficiency), Cushing's syndrome (hypercortisolism), and congenital adrenal hyperplasia (CAH).

A leukocyte count, also known as a white blood cell (WBC) count, is a laboratory test that measures the number of leukocytes in a sample of blood. Leukocytes are a vital part of the body's immune system and help fight infection and inflammation. A high or low leukocyte count may indicate an underlying medical condition, such as an infection, inflammation, or a bone marrow disorder. The normal range for a leukocyte count in adults is typically between 4,500 and 11,000 cells per microliter (mcL) of blood. However, the normal range can vary slightly depending on the laboratory and the individual's age and sex.

Benzoquinones are a type of chemical compound that contain a benzene ring (a cyclic arrangement of six carbon atoms) with two ketone functional groups (-C=O) in the 1,4-positions. They exist in two stable forms, namely ortho-benzoquinone and para-benzoquinone, depending on the orientation of the ketone groups relative to each other.

Benzoquinones are important intermediates in various biological processes and are also used in industrial applications such as dyes, pigments, and pharmaceuticals. They can be produced synthetically or obtained naturally from certain plants and microorganisms.

In the medical field, benzoquinones have been studied for their potential therapeutic effects, particularly in the treatment of cancer and infectious diseases. However, they are also known to exhibit toxicity and may cause adverse reactions in some individuals. Therefore, further research is needed to fully understand their mechanisms of action and potential risks before they can be safely used as drugs or therapies.

Chemotaxis is a term used in biology and medicine to describe the movement of an organism or cell towards or away from a chemical stimulus. This process plays a crucial role in various biological phenomena, including immune responses, wound healing, and the development and progression of diseases such as cancer.

In chemotaxis, cells can detect and respond to changes in the concentration of specific chemicals, known as chemoattractants or chemorepellents, in their environment. These chemicals bind to receptors on the cell surface, triggering a series of intracellular signaling events that ultimately lead to changes in the cytoskeleton and directed movement of the cell towards or away from the chemical gradient.

For example, during an immune response, white blood cells called neutrophils use chemotaxis to migrate towards sites of infection or inflammation, where they can attack and destroy invading pathogens. Similarly, cancer cells can use chemotaxis to migrate towards blood vessels and metastasize to other parts of the body.

Understanding chemotaxis is important for developing new therapies and treatments for a variety of diseases, including cancer, infectious diseases, and inflammatory disorders.

Ketotifen is an antihistamine and mast cell stabilizer used in the prevention and treatment of allergic reactions. It works by blocking the release of histamine, a substance that causes allergic symptoms, and preventing the activation of mast cells, which play a key role in allergic responses. Ketotifen is available as an oral medication and is often used to treat chronic urticaria (hives) and other allergic conditions. It may also have some benefits in the treatment of asthma.

It's important to note that ketotifen should be taken under the supervision of a healthcare professional, as it can cause side effects such as drowsiness, dry mouth, and increased appetite. Additionally, it may interact with other medications, so it is important to inform your doctor of all medications you are taking before starting ketotifen.

Bronchial hyperresponsiveness (BHR) or bronchial hyperreactivity (BH) is a medical term that refers to the increased sensitivity and exaggerated response of the airways to various stimuli. In people with BHR, the airways narrow (constrict) more than usual in response to certain triggers such as allergens, cold air, exercise, or irritants like smoke or fumes. This narrowing can cause symptoms such as wheezing, coughing, chest tightness, and shortness of breath.

BHR is often associated with asthma and other respiratory conditions, including chronic obstructive pulmonary disease (COPD) and bronchiectasis. It is typically diagnosed through a series of tests that measure the degree of airway narrowing in response to various stimuli. These tests may include spirometry, methacholine challenge test, or histamine challenge test.

BHR can be managed with medications such as bronchodilators and anti-inflammatory drugs, which help to relax the muscles around the airways and reduce inflammation. It is also important to avoid triggers that can exacerbate symptoms and make BHR worse.

Superoxides are partially reduced derivatives of oxygen that contain one extra electron, giving them an overall charge of -1. They are highly reactive and unstable, with the most common superoxide being the hydroxyl radical (•OH-) and the superoxide anion (O2-). Superoxides are produced naturally in the body during metabolic processes, particularly within the mitochondria during cellular respiration. They play a role in various physiological processes, but when produced in excess or not properly neutralized, they can contribute to oxidative stress and damage to cells and tissues, potentially leading to the development of various diseases such as cancer, atherosclerosis, and neurodegenerative disorders.

Allergic rhinitis, perennial type, is a medical condition characterized by inflammation of the nasal passages caused by an allergic response to environmental allergens that are present throughout the year. Unlike seasonal allergic rhinitis, which is triggered by specific pollens or molds during certain times of the year, perennial allergic rhinitis is a persistent condition that occurs year-round.

Common allergens responsible for perennial allergic rhinitis include dust mites, cockroaches, pet dander, and indoor mold spores. Symptoms may include sneezing, runny or stuffy nose, itchy eyes, ears, throat, or roof of the mouth. Treatment options typically involve avoiding exposure to the offending allergens, if possible, as well as medications such as antihistamines, nasal corticosteroids, and leukotriene receptor antagonists to manage symptoms. Immunotherapy (allergy shots) may also be recommended for long-term management in some cases.

Histamine antagonists, also known as histamine blockers or H1-blockers, are a class of medications that work by blocking the action of histamine, a substance in the body that is released during an allergic reaction. Histamine causes many of the symptoms of an allergic response, such as itching, sneezing, runny nose, and hives. By blocking the effects of histamine, these medications can help to relieve or prevent allergy symptoms.

Histamine antagonists are often used to treat conditions such as hay fever, hives, and other allergic reactions. They may also be used to treat stomach ulcers caused by excessive production of stomach acid. Some examples of histamine antagonists include diphenhydramine (Benadryl), loratadine (Claritin), and famotidine (Pepcid).

It's important to note that while histamine antagonists can be effective at relieving allergy symptoms, they do not cure allergies or prevent the release of histamine. They simply block its effects. It's also worth noting that these medications can have side effects, such as drowsiness, dry mouth, and dizziness, so it's important to follow your healthcare provider's instructions carefully when taking them.

Hypersensitivity is an exaggerated or inappropriate immune response to a substance that is generally harmless to most people. It's also known as an allergic reaction. This abnormal response can be caused by various types of immunological mechanisms, including antibody-mediated reactions (types I, II, and III) and cell-mediated reactions (type IV). The severity of the hypersensitivity reaction can range from mild discomfort to life-threatening conditions. Common examples of hypersensitivity reactions include allergic rhinitis, asthma, atopic dermatitis, food allergies, and anaphylaxis.

Nasal obstruction is a medical condition that refers to any blockage or restriction in the normal flow of air through the nasal passages. This can be caused by various factors such as inflammation, swelling, or physical abnormalities in the nasal cavity. Common causes of nasal obstruction include allergies, sinusitis, deviated septum, enlarged turbinates, and nasal polyps. Symptoms may include difficulty breathing through the nose, nasal congestion, and nasal discharge. Treatment options depend on the underlying cause and may include medications, surgery, or lifestyle changes.

Pertussis toxin is an exotoxin produced by the bacterium Bordetella pertussis, which is responsible for causing whooping cough in humans. This toxin has several effects on the host organism, including:

1. Adenylyl cyclase activation: Pertussis toxin enters the host cell and modifies a specific G protein (Gαi), leading to the continuous activation of adenylyl cyclase. This results in increased levels of intracellular cAMP, which disrupts various cellular processes.
2. Inhibition of immune response: Pertussis toxin impairs the host's immune response by inhibiting the migration and function of immune cells like neutrophils and macrophages. It also interferes with antigen presentation and T-cell activation, making it difficult for the body to clear the infection.
3. Increased inflammation: The continuous activation of adenylyl cyclase by pertussis toxin leads to increased production of proinflammatory cytokines, contributing to the severe coughing fits and other symptoms associated with whooping cough.

Pertussis toxin is an essential virulence factor for Bordetella pertussis, and its effects contribute significantly to the pathogenesis of whooping cough. Vaccination against pertussis includes inactivated or genetically detoxified forms of pertussis toxin, which provide immunity without causing disease symptoms.

Monocytes are a type of white blood cell that are part of the immune system. They are large cells with a round or oval shape and a nucleus that is typically indented or horseshoe-shaped. Monocytes are produced in the bone marrow and then circulate in the bloodstream, where they can differentiate into other types of immune cells such as macrophages and dendritic cells.

Monocytes play an important role in the body's defense against infection and tissue damage. They are able to engulf and digest foreign particles, microorganisms, and dead or damaged cells, which helps to clear them from the body. Monocytes also produce cytokines, which are signaling molecules that help to coordinate the immune response.

Elevated levels of monocytes in the bloodstream can be a sign of an ongoing infection, inflammation, or other medical conditions such as cancer or autoimmune disorders.

Prostaglandin endoperoxides are naturally occurring lipid compounds that play important roles as mediators in the body's inflammatory and physiological responses. They are intermediate products in the conversion of arachidonic acid to prostaglandins and thromboxanes, which are synthesized by the action of enzymes called cyclooxygenases (COX-1 and COX-2).

Synthetic prostaglandin endoperoxides, on the other hand, are chemically synthesized versions of these compounds. They are used in medical research and therapeutic applications to mimic or inhibit the effects of naturally occurring prostaglandin endoperoxides. These synthetic compounds can be used to study the mechanisms of prostaglandin action, develop new drugs, or as stand-in agents for the natural compounds in experimental settings.

It's important to note that while synthetic prostaglandin endoperoxides can serve as useful tools in research and medicine, they also carry potential risks and side effects, much like their naturally occurring counterparts. Therefore, their use should be carefully monitored and regulated to ensure safety and efficacy.

Interleukin-8 (IL-8) is a type of cytokine, which is a small signaling protein involved in immune response and inflammation. IL-8 is also known as neutrophil chemotactic factor or NCF because it attracts neutrophils, a type of white blood cell, to the site of infection or injury.

IL-8 is produced by various cells including macrophages, epithelial cells, and endothelial cells in response to bacterial or inflammatory stimuli. It acts by binding to specific receptors called CXCR1 and CXCR2 on the surface of neutrophils, which triggers a series of intracellular signaling events leading to neutrophil activation, migration, and degranulation.

IL-8 plays an important role in the recruitment of neutrophils to the site of infection or tissue damage, where they can phagocytose and destroy invading microorganisms. However, excessive or prolonged production of IL-8 has been implicated in various inflammatory diseases such as chronic obstructive pulmonary disease (COPD), rheumatoid arthritis, and cancer.

Leukotriene B4 receptor 1) - LTB4R BLT2 (Leukotriene B4 receptor 2) - LTB4R2 Cysteinyl leukotriene receptors (CysLTRs) - bind ... The leukotriene (LT) receptors are G protein-coupled receptors that bind and are activated by the leukotrienes. They include ... IUPHAR GPCR Database - Leukotriene receptors Leukotriene+Receptors at the U.S. National Library of Medicine Medical Subject ... Eicosanoid receptor Oxoeicosanoid receptor Prostaglandin receptor Thromboxane receptor Kanaoka Y, Maekawa A, Austen KF (2013 ...
The cysteinyl leukotriene receptors (CysLTRs) include the following two receptors: Cysteinyl leukotriene receptor 1 (CysLTR1) ... Leukotriene receptor Eicosanoid receptor Kanaoka Y, Maekawa A, Austen KF (2013). "Identification of GPR99 protein as a ... potential third cysteinyl leukotriene receptor with a preference for leukotriene E4 ligand". J. Biol. Chem. 288 (16): 10967-72 ... Cysteinyl leukotriene receptor 2 (CysLTR2) The recently elucidated CysLTE, represented by GPR99/OXGR1, may constitute a third ...
... 1 (BLTR1) Leukotriene B4 receptor 2 (BLTR2) Eicosanoid receptor Leukotriene receptor v t e (Articles ... The leukotriene B4 receptors (BLTRs) include the following two receptors: ... with short description, Short description matches Wikidata, G protein-coupled receptors, All stub articles, Transmembrane ...
... , also termed CYSLTR2, is a receptor for cysteinyl leukotrienes (LT) (see leukotrienes# ... "Leukotriene Receptors: CysLT2". IUPHAR Database of Receptors and Ion Channels. International Union of Basic and Clinical ... 2006). "Cysteinyl leukotriene 2 receptor and protease-activated receptor 1 activate strongly correlated early genes in human ... Cysteinyl leukotriene receptor 1 Eicosanoid receptor GPR99 GRCh38: Ensembl release 89: ENSG00000152207 - Ensembl, May 2017 ...
... is a protein that in humans is encoded by the LTB4R gene. Eicosanoid receptor Etalocib, an antagonist ... "Leukotriene Receptors: BLT1". IUPHAR Database of Receptors and Ion Channels. International Union of Basic and Clinical ... LTB4R leukotriene B4 receptor". Raport CJ, Schweickart VL, Chantry D, et al. (1996). "New members of the chemokine receptor ... 2000). "A second leukotriene B(4) receptor, BLT2. A new therapeutic target in inflammation and immunological disorders". J. Exp ...
Discovered several years after the leukotriene B4 receptor 1 (BLT1), BLT2 receptor binds leukotriene B4 (LTB4) with far lower ... Leukotriene B4 receptor 2, also known as BLT2, BLT2 receptor, and BLTR2, is an Integral membrane protein that is encoded by the ... "BLT2 receptor , Leukotriene receptors ,". IUPHAR/BPS Guide to PHARMACOLOGY. Matsunaga Y, Fukuyama S, Okuno T, Sasaki F, ... Tager AM, Luster AD (2003). "BLT1 and BLT2: the leukotriene B(4) receptors". Prostaglandins, Leukotrienes, and Essential Fatty ...
It has been discovered that two types of said receptor exist, the CysLT1 receptor as well as the CysLT2 receptor. Leukotriene- ... They bind to cysteinyl leukotriene receptors (CysLT). One of those receptors is CysLT type-1 (CysLT1) and can be found in many ... When looking for leukotriene receptor antagonists, researchers began without any assistance of ligand-receptor binding data and ... Cysteinyl-leukotriene type 1 receptor antagonists, also known as CysLT1 antagonists, are a class of drugs that hinder the ...
... may occur in asthma patients being treated with leukotriene ... Leukotriene antagonist Skin lesion James, William; Berger, Timothy; Elston, Dirk (2005). Andrews' Diseases of the Skin: ... receptor antagonists, occurring 2 days to 10 months after the antagonist has been started, with features of the syndrome ...
"Leukotriene Receptors: OXE". IUPHAR Database of Receptors and Ion Channels. International Union of Basic and Clinical ... niacin receptor 1, and niacin receptor 2 may include the recently defined receptor for 12-HETE, GPR31, not only in its amino ... family of G protein-coupled receptors whose three members are HCA1 (GPR81), HCA2 (Niacin receptor 1), and HCA3 (Niacin receptor ... Oxoeicosanoid receptor 1 (OXER1) also known as G-protein coupled receptor 170 (GPR170) is a protein that in humans is encoded ...
Ferguson L, Futamura M, Vakirlis E, Kojima R, Sasaki H, Roberts A, Mori R (October 2018). "Leukotriene receptor antagonists for ... Antidepressants and naltrexone may be used to control pruritus (itchiness). Leukotriene inhibitors such as montelukast are of ...
"Pharmacogenomics of Prostaglandin and Leukotriene Receptors". Frontiers in Pharmacology. 7: 316. doi:10.3389/fphar.2016.00316. ... Prostaglandin DP1 receptor Prostaglandin receptors Prostanoid receptors Eicosanoid receptor GRCh38: Ensembl release 89: ... with the C5a receptor, Formyl peptide receptor 1, and Formyl peptide receptor 2 receptors. DP2 has little or no such amino acid ... "DP2 receptor - Prostanoid receptors - IUPHAR/BPS Guide to PHARMACOLOGY". www.guidetopharmacology.org. Oguma T, Asano K, ...
"Pharmacogenomics of Prostaglandin and Leukotriene Receptors". Frontiers in Pharmacology. 7: 316. doi:10.3389/fphar.2016.00316. ... Eicosanoid receptor Prostaglandin E2 receptor 1 (EP1) Prostaglandin E2 receptor 2 (EP2) Prostaglandin E2 receptor 4 (EP4) ... EP3 receptor-deficient mice and/or wild type mice treated with an EP3 receptor agonist are similarly protected from allergic ... Prostaglandin EP3 receptor (53kDa), also known as EP3, is a prostaglandin receptor for prostaglandin E2 (PGE2) encoded by the ...
CystLT1 is a receptor for a specific class of leukotrienes that contain the amino acid cysteine. These cysteinyl leukotrienes ... Zafirlukast is an antagonist of cysteinyl leukotriene receptor 1 (CysLT1), a receptor found throughout the smooth muscle of the ... Like other leukotriene receptor antagonists, zafirlukast is thought to be useful for the long-term treatment of asthma, but it ... Capra V, Thompson MD, Sala A, Cole DE, Folco G, Rovati GE (July 2007). "Cysteinyl-leukotrienes and their receptors in asthma ...
"Pharmacogenomics of Prostaglandin and Leukotriene Receptors". Frontiers in Pharmacology. 7: 316. doi:10.3389/fphar.2016.00316. ... Prostanoid receptors Prostaglandin receptors Prostaglandin E2 receptor 1 (EP1) Prostaglandin E2 receptor 3 (EP3) Prostaglandin ... Prostaglandin E2 receptor 2, also known as EP2, is a prostaglandin receptor for prostaglandin E2 (PGE2) encoded by the human ... "Prostanoid Receptor: EP2". IUPHAR Database of Receptors and Ion Channels. International Union of Basic and Clinical ...
The TP receptor appears to play and essential role in the pro-asthmatic actions of leukotriene C4 (LTC4): in ovalbumin- ... These receptor down regulating events are triggered by the G protein-coupled receptor kinases mobilized during TP receptor ... The thromboxane receptor is one among the five classes of prostanoid receptors and was the first eicosanoid receptor cloned. ... The thromboxane receptor (TP) also known as the prostanoid TP receptor is a protein that in humans is encoded by the TBXA2R ...
"Pharmacogenomics of Prostaglandin and Leukotriene Receptors". Frontiers in Pharmacology. 7: 316. doi:10.3389/fphar.2016.00316. ... Prostaglandin E2 receptor 1 (EP1) Prostaglandin E2 receptor 2 (EP2) Prostaglandin E2 receptor 3 (EP3) Eicosanoid receptor ... EP4 receptors are highly expressed in the small intestine and colon. Mice lacking this receptor or treated with a selective EP4 ... The EP4 receptor is over-expressed in human prostate cancer tissue and a selective EP4-receptor antagonist inhibits the growth ...
Lewis JH, Stine JG (2013). "Nonsteroidal Antiinflammatory Drugs and Leukotriene Receptor Antagonists". In Kaplowitz N, DeLeve ...
Lewis JH, Stine JG (2013). "Nonsteroidal Antiinflammatory Drugs and Leukotriene Receptor Antagonists. Chapter 22". In Kaplowitz ...
... an agonist of Leukotriene B4 receptors (i.e. BLT2 receptors) and mediator of certain BLT2 receptor actions. The enzyme plays a ... Yokomizo T (February 2015). "Two distinct leukotriene B4 receptors, BLT1 and BLT2". Journal of Biochemistry. 157 (2): 65-71. ... 10E-trienoic acid is a natural ligand for leukotriene B4 receptor 2". The Journal of Experimental Medicine. 205 (4): 759-766. ... Picotamide acts both as a thromboxane synthase inhibitor and as a thromboxane receptor antagonist. The human thromboxane A (TXA ...
Leukotriene B4 receptor 1 (BLT1 receptor) and its low affinity BLT2 receptor (Kd=23 nM); both receptors are G protein coupled ... cell carcinoma Esophageal cancer Pancreatic cancer Colon cancer Leukotriene B4 receptor 2 Leukotriene B4 receptor 1 Leukotriene ... Tager, A. M.; Luster, A. D. (2003). "BLT1 and BLT2: The leukotriene B(4) receptors". Prostaglandins, Leukotrienes, and ... BLT2, also called leukotriene B4 receptor 2, is closely associated with 12-HHT in stimulation of metastasis (malignant behavior ...
Yokomizo, T. (2014). "Two distinct leukotriene B4 receptors, BLT1 and BLT2". Journal of Biochemistry. 157 (2): 65-71. doi: ... Receptors that mediate TXA2 actions are thromboxane A2 receptors. The human TXA2 receptor (TP) is a typical G protein-coupled ... In humans, two TP receptor splice variants - TPα and TPβ - have so far been cloned. TXA2 is generated from prostaglandin H2 by ... This is achieved by activating the thromboxane receptor, which results in platelet-shape change, inside-out activation of ...
... cysteinyl leukotriene receptor 1 and cysteinyl leukotriene receptor 2) and the purine P2Y subfamily of 12 receptors (see P2Y ... Uracil nucleotide/cysteinyl leukotriene receptor is a G protein-coupled receptor that in humans is encoded by the GPR17 gene ... "The orphan receptor GPR17 identified as a new dual uracil nucleotides/cysteinyl-leukotrienes receptor". The EMBO Journal. 25 ( ... GPR17 is a promiscuous receptor. Montelukast which inhibits cysteinyl leukotriene receptor 1 and is in clinical use for the ...
The medications, montelukast and zafirlukast block leukotriene receptors and can be used as add on treatment or in isolation ... Pacor ML, Di Lorenzo G, Corrocher R (2001). "Efficacy of leukotriene receptor antagonist in chronic urticaria. A double-blind, ... AU Erbagci Z SO (2002). "The leukotriene receptor antagonist montelukast in the treatment of chronic idiopathic urticaria: a ... or adding a leukotriene receptor antagonist such as montelukast. Step 3 consists of adding or replacing the current treatment ...
Cysteinyl leukotriene receptor 1 (CysLTR1) and Cysteinyl leukotriene receptor 2 (CysLTR2), both of which appear to be ... the drug does not block the cysteinyl leukotriene receptor 2) (see cysteinyl leukotriene receptor 1#Clinical significance). The ... 2-Oxoglutarate receptor 1 (OXGR1), also known as cysteinyl leukotriene receptor E (CysLTE) and GPR99, is a protein that in ... "Identification of GPR99 protein as a potential third cysteinyl leukotriene receptor with a preference for leukotriene E4 ligand ...
Montelukast, Zafirlukast, and Pranlukast are receptor antagonists for the cysteinyl leukotriene receptor 1 which contributes to ... leukotriene A4 LTA4, which is then either rapidly converted to leukotriene B4 (LTB4) by leukotriene-A4 hydrolase (LTA4H) or to ... leukotriene-A4 hydrolase), or are the cellular receptors responsible for mediating the cellular responses to the down-stream ... leukotriene-A4 hydrolase, to form the dihydroxyl product, leukotriene B4 (LTB4, i.e. 5S,12R-dihydroxy-5S,6Z,8E,10E,12R,14Z- ...
Leukotriene receptor antagonist-based medications and methylxanthines are not recommended for treating children with persistent ... These receptors include rapidly adapting receptors which respond to mechanical stimuli, slowly adapting receptors, and ... Chang AB, Winter D, Acworth JP (April 2006). Chang AB (ed.). "Leukotriene receptor antagonist for prolonged non-specific cough ... Postnasal drip coughing can be caused by the direct irritation of the postnasal drip or by inflammation of cough receptors in ...
Leukotriene antagonists block receptors targeted by leukotrienes released from mast cells. Mast cell stabilizers help prevent ... Mast cells express a cell surface receptor, c-kit (CD117), which is the receptor for stem cell factor (scf). In laboratory ... Mutations of the gene coding for the c-kit receptor (mutation KIT(D816V)), leading to constitutive signalling through the ... Antihistamines block receptors targeted by histamine released from mast cells. Both H1 and H2 blockers may be helpful, often in ...
... recognition of a distinct receptor preferential for leukotriene E4 in mice lacking the cysteinyl leukotriene 1 and 2 receptors ... Leukotriene E4 (LTE4) is a cysteinyl leukotriene involved in inflammation. It is known to be produced by several types of white ... Lee CW, Lewis RA, Corey EJ, Austen KF (1983). "Conversion of leukotriene D4 to leukotriene E4 by a dipeptidase released from ... "Leukotriene E4-induced pulmonary inflammation is mediated by the P2Y12 receptor". The Journal of Experimental Medicine. 206 (11 ...
... activates the Leukotriene B4 receptor, Leukotriene B4 receptor 2 (BLT2) but not its Leukotriene B4 receptor 1 (BLT1). This ... GPR31 and the Leukotriene B4 receptor 2; 12S-HETE also acts as a receptor antagonist by binding to but not stimulating the ... HETE bind to and activate the Leukotriene B4 receptor 2, activate the Peroxisome proliferator-activated receptor gamma, and at ... "Hydroxyeicosanoids bind to and activate the low affinity leukotriene B4 receptor, BLT2". The Journal of Biological Chemistry. ...
LXA4 and 15-epi-LXA4 are also high affinity antagonists of the cysteinyl leukotriene receptor 1 for which leukotrienes (LT) ... FPR2, which is now termed the ALX, ALX/FPR, or ALX/FPR2 receptor, is a G protein coupled receptor initially identified as a ... 2005). "Anti-inflammatory circuitry: Lipoxin, aspirin-triggered lipoxins and their receptor ALX". Prostaglandins, Leukotrienes ... LXA4 and 15-epi-LXA4 are high affinity receptor ligands for and activators of the FPR2 receptor. ...
... , also termed CYSLTR1, is a receptor for cysteinyl leukotrienes (LT) (see leukotrienes# ... Other cysLT receptors include cysteinyl leukotriene receptor 2 (i.e. CysLTR2) and GPR99 (also termed the oxoglutarate receptor ... "Leukotriene Receptors: CysLT1". IUPHAR Database of Receptors and Ion Channels. International Union of Basic and Clinical ... Mellor EA, Maekawa A, Austen KF, Boyce JA (July 2001). "Cysteinyl leukotriene receptor 1 is also a pyrimidinergic receptor and ...
CysLT1 (Cysteinyl leukotriene receptor 1) - CYSLTR1;CYSLTR1 is the receptor for Leukotriene C4 and Leukotriene D4; in binds and ... Leukotrienes: BLT1 (Leukotriene B4 receptor) - LTB4R; BLT1 is the primary receptor for leukotriene B4. Relative potencies in ... Cysteinyl leukotriene receptor 2) - CYSLTR2; Similar to CYSLTR1, CYSLTR2 is the receptor for Leukotriene C4 and Leukotriene D4 ... BLT2 (Leukotriene B4 receptor 2) - LTB4R2; the receptor for 12-Hydroxyheptadecatrienoic acid, leukotriene B4, and certain other ...
... the leukotriene B4 receptors. However, further studies in neutrophils indicated that 5-(S)-HETE acts through a receptor ... leukotriene B4, leukotriene C4, leukotriene D4, leukotriene E4, lipoxin A4, and lipoxin B4. It and other members of the 5-(S)- ... Leukotriene A4 may then be further metabolized either to leukotriene B4 by leukotriene A4 hydrolase or to leukotriene C4 by ... Finally, leukotriene C4 may be metabolized to leukotriene D4 and then to leukotriene E4. The relative amounts of these ...
Leukotrienes, and Essential Fatty Acids. 65 (2): 79-83. doi:10.1054/plef.2001.0292. PMID 11545623. "Prostanoid Receptors: IP1 ... The Prostacyclin receptor, also termed the prostaglandin I2 receptor or just IP, is a receptor belonging to the prostaglandin ( ... IP receptors also appear involved in suppressing non-allergic inflammatory responses. IP receptor-deficient mice exhibit a ... These and further studies using IP receptor antagonists in rats indicate that IP receptors on pain-perceiving sensory neurons ...
"Identification of GPR99 protein as a potential third cysteinyl leukotriene receptor with a preference for leukotriene E4 ligand ... LXXXIV: leukotriene receptor nomenclature, distribution, and pathophysiological functions". Pharmacological Reviews. 63 (3): ... the cellular receptors (see Cell surface receptor) that they stimulate or, where noted, antagonize to attain this activity, ... LTA4 is then metabolized either to LTB4 by leukotriene A4 hydrolase or leukotriene C4 (LTC4) by either LTC4 synthase or ...
In contrast, PPARα is activated by leukotriene B4. Certain members of the 15-hydroxyeicosatetraenoic acid family of arachidonic ... In the field of molecular biology, the peroxisome proliferator-activated receptors (PPARs) are a group of nuclear receptor ... peroxisome proliferator-activated receptors are nuclear receptors at the crossroads of key cellular functions". Prog. Lipid Res ... Receptors - the Peroxisome Proliferator-Activated Receptor Structure in Interactive 3D (Articles with short description, Short ...
Di Marzo V, De Petrocellis L, Fezza F, Ligresti A, Bisogno T (2002). "Anandamide receptors". Prostaglandins, Leukotrienes, and ... but instead activate other receptors (e.g. peroxisome proliferator-activated receptors (PPAR)-α/γ, G-protein coupled receptors ... Beside the CB1 receptors being triggers of the generation of ceramides that mediate neuronal cell fate, the skin CB1 receptor ... OEA acting mostly at peroxisome proliferator‐activated receptor‐α (PPAR‐α) nuclear receptors and, to some extent, TRPV1 ...
Leukotriene B4 receptor 1) - LTB4R BLT2 (Leukotriene B4 receptor 2) - LTB4R2 Cysteinyl leukotriene receptors (CysLTRs) - bind ... The leukotriene (LT) receptors are G protein-coupled receptors that bind and are activated by the leukotrienes. They include ... IUPHAR GPCR Database - Leukotriene receptors Leukotriene+Receptors at the U.S. National Library of Medicine Medical Subject ... Eicosanoid receptor Oxoeicosanoid receptor Prostaglandin receptor Thromboxane receptor Kanaoka Y, Maekawa A, Austen KF (2013 ...
To assess their roles, we investigated the distribution of their receptors, CysLT(1) and CysLT(2), in the cardiovascular system ... Cysteinyl leukotrienes (LTC(4), LTD(4), and LTE(4)) are a class of biologically active lipids that exert potent effects on the ... Functional characterization of cysteinyl leukotriene CysLT(2) receptor on human coronary artery smooth muscle cells Biochem ... Cysteinyl leukotrienes (LTC(4), LTD(4), and LTE(4)) are a class of biologically active lipids that exert potent effects on the ...
A selective and competitive inhibitor of the cysteinyl leukotriene receptor. Cysteinyl leukotrienes and leukotriene receptor ... Inhibits bronchoconstriction as competitive receptor antagonist of leukotrienes D4 & E4; receptor occupation and cysteinyl ... Histamine 1 receptor antagonists (antihistamines). Class Summary. Type 1 histamine-receptor blockers act to block action of ... Leukotriene inhibitors. Class Summary. Leukotrienes are synthesized by degranulated mast cells and basophils and contribute to ...
Prenatal leukotriene receptor antagonist use is not associated with a higher incidence of neuropsychiatric events in their ... Prenatal leukotriene receptor antagonist use and neuropsychiatric outcomes. ↓This is a sponsored advert: Please read the ... Prenatal leukotriene receptor antagonist use is not associated with a higher incidence of neuropsychiatric events in their ... Use of Leukotriene-Receptor Antagonists During Pregnancy and Risk of Neuropsychiatric Events in Offspring. JAMA Netw Open 2023 ...
The leukotriene structure-like receptor antagonists, e.g., SK&F 104353 and SK&F 104373, also competed with the [3H]ICI-198615 ... Binding of radiolabeled high affinity antagonist to leukotriene D4 receptor in guinea pig lung membranes: interconversion of ... The kinetic parameters and the pharmacological specificity of a high affinity leukotriene D4 (LTD4) receptor antagonist, ICI- ... Binding of radiolabeled high affinity antagonist to leukotriene D4 receptor in guinea pig lung membranes: interconversion of ...
Late-breaking data adds important safety and efficacy data for leukotriene receptor antagonists augmentation in chronic ... Leukotriene Receptor Antagonists as Add-on Therapy to Antihistamines for Urticaria: Systematic Review and Meta-Analysis of ... Efficacy and Safety Data for Leukotriene Receptor Antagonists for Chronic Urticaria Presented at ACAAI. November 12, 2023. ... The investigators only had moderate certainty in terms of the safety outcomes; they noted that adding leukotriene receptor ...
Binding affinity against Cysteinyl leukotriene D4 receptor from guinea pig lung membrane. ...
T1 - Effects of monotherapy with intra-nasal corticosteroid or combines oral histamine and leukotriene receptor antagonists in ... 2001). Effects of monotherapy with intra-nasal corticosteroid or combines oral histamine and leukotriene receptor antagonists ... Effects of monotherapy with intra-nasal corticosteroid or combines oral histamine and leukotriene receptor antagonists in ... Effects of monotherapy with intra-nasal corticosteroid or combines oral histamine and leukotriene receptor antagonists in ...
Asmalair is indicated in the treatment of asthma as add-on therapy in those patients with mild to moderate persistent asthma ...
LifeSpan has used multiple antibodies to study the localization profile of the Leukotriene B4 Receptor / BLT1 protein across an ...
For these, reasons both leukotriene synthesis inhibitors and leukotriene receptor antagonists have been suggested for inducing ... Many studies regarding myocardial ischemia and reperfusion show that leukotriene signaling may be involved in the development ... is an important substrate for the production of a group of lipid mediators known as leukotrienes, which induce proinflammatory ... signaling through the activation of specific BLT and CysLT receptors. The interaction of these substances in the vascular wall ...
In the late 1970s, it became evident that the cysteinyl leukotrienes, leukotriene C4, leukotriene D4 and leukotriene E4 (Figure ... Leukotriene-receptor antagonists. Leukotriene synthesis. November 15, 2018. November 22, 2021. John BuducciAsthma Management ... Leukotriene-receptor antagonists. Pharmacologic considerations. *If the pediatrician says that my toddler has "a wheezy chest ... Leukotriene-receptor antagonists currently available for clinical use exert their biological effects by selectively binding to ...
Potent and selective antagonist of leukotriene D4 (LTD4) at the cysteinyl leukotriene receptor, CysLT1. ... Leukotriene receptor antagonists. Class Summary. Prevent or reverse some of the pathologic features associated with the ... Inhibits release of histamine, leukotrienes, and other mediators from sensitized mast cells. It also inhibits the influx of ... Successful treatment with other anti-inflammatory medications, such as leukotriene modifiers (eg, montelukast) and mast cell ...
Another leukotriene receptor antagonist is montelukast (Singulair), taken once daily. Zileuton (Zyflo), also used in the ... Zafirlukast blocks the action of the cysteinyl leukotrienes on the CysLT1 receptors, thus reducing constriction of the airways ... Zafirlukast is an oral leukotriene receptor antagonist (LTRA) for the maintenance treatment of asthma, often used in ... Zafirlukast: the first leukotriene-receptor antagonist approved for the treatment of asthma. Ann Pharmacother. 1997 Sep;31(9): ...
Leukotriene receptor antagonist for prolonged non-specific cough in children. Overview of attention for article published in ...
Background Transient receptor potential cation channel subfamily V member 1 (TRPV1) are sensitive to heat, capsaicin, pungent ... Two major G-Protein-coupled receptors for Leukotriene B4 have been identified: the high affinity receptor BLT1 and the low ... leukotriene synthesis inhibitors and leukotriene receptor antagonists, and (d) production of a shock-like state by exogenous ... innovative experiments measuring leukotrienes in bile and other body fluids and in employing specific leukotriene receptor ...
... leukotriene receptor antagonists, and phosphodiesterase type-4 inh 3.3.2. Leukotriene receptor antagonists. ... Cromoglicate and related therapy, leukotriene receptor antagonists, and phosphodiesterase type-4 inh ... Cromoglicate and related therapy, leukotriene receptor antagonists, and phosphodiesterase type-4 inh ...
leukotriene receptor agonists, such as: *zafirlukast (Accolate). *montelukast (Singulair). *immunomodulators, such as: * ... The drugs mechanism of action (the way it works) is to attach to beta-receptors (docking stations) in your airways. This helps ... The drug works by attaching to beta-receptors (docking stations) in your airways. This helps relax the muscles in your airways ... The drug works by attaching to beta-receptors (docking stations) in your airways. This helps relax the muscles in your airways ...
... are members of the nuclear hormone receptor superfamily of ligand-activated transcription factors that are related to retinoid ... LTB4: Leukotriene B-4. N-CoR: Nuclear receptor corepessor. NSAID: Non steroidal anti inflammatory. NCoA-1: Nuclear receptor ... SRC-1: Steroid receptor coactivator-1. TRAC: Thyroid hormone receptor-associating cofactor. TRAP: Thyroid receptor-associated ... The nuclear receptor corepressor (N-CoR) or silencing mediator of retinoid and thyroid receptors (SMRT) proteins bind and ...
E viewed as not merely an aesthetic Leukotriene Receptor MedChemExpress concern, but rather may also be connected to overall ... E viewed as not merely an aesthetic Leukotriene Receptor MedChemExpress concern, but rather may also be connected to overall ... Uncategorized , E viewed as not merely an aesthetic Leukotriene Receptor MedChemExpress concern, but rather may also ... E viewed as not merely an aesthetic Leukotriene Receptor MedChemExpress concern, but rather may also ...
This medication belongs to a group of drugs called leukotriene receptor antagonists. It works by blocking the actions of ... leukotriene, a natural substance that causes swelling and tightening of the airways. ...
Creticos P, Knobil K, Edwards LD, Rickard KA, Dorinsky P. Loss of response to treatment with leukotriene receptor antagonists ... Creticos, P, Knobil, K, Edwards, LD, Rickard, KA & Dorinsky, P 2002, Loss of response to treatment with leukotriene receptor ... Dive into the research topics of Loss of response to treatment with leukotriene receptor antagonists but not inhaled ... Loss of response to treatment with leukotriene receptor antagonists but not inhaled corticosteroids in patients over 50 years ...
cysteinyl leukotriene ,Cys-LT,. Cysteinylleukotrien {n}. ,Cys-LT,. biochem.. cysteinyl leukotriene receptor. ...
Asero R, Tedeschi A, Lorini M. Leukotriene receptor antagonists in chronic urticaria. Allergy. 2001 May. 56(5):456-7. [QxMD ... Leukotrienes, for example, may play an important role in the onset of angioedema that is induced by nonsteroidal anti- ... In 0-9.2% of cases, patients with ACEI-AAE may develop angioedema when switching to an angiotensin II receptor blocker (ARB). [ ... Mast cells can also be activated by other non-IgE-mediated processes, such as the binding of IgG antibodies to IgE receptors on ...
... treatment reduced urinary prostaglandin F2α and leukotriene E4 levels and therefore, NVP-1703 can be treatment option for ...
Montelukast is in a class of medications called leukotriene receptor antagonists (LTRAs). It works by blocking the action of ...
Molecular targets of SIRT1 include LKB1 and peroxisome proliferator-activated receptor γ co-activator α (PGC1α), which is also ... Prostaglandins, Leukotrienes and Essential Fatty Acids, 70, 253-264.. CAS Google Scholar ... Cullingford, T. E. (2004). The ketogenic diet; fatty acids, fatty acid-activated receptors and neurological disorders. ... When insulin and free IGF-1 bind to their specific tyrosine kinase receptors they activate the phosphatidylinositol-3 kinase ( ...
... is a selective and orally active leukotriene receptor antagonist that inhibits the cysteinyl leukotriene CysLT1 receptor. ... These eicosanoids bind to cysteinyl leukotriene (CysLT) receptors. The CysLT type-1 (CysLT1) receptor is found in the human ... Montelukast sodium is a leukotriene receptor antagonist indicated for: *Prophylaxis and chronic treatment of asthma in patients ... Montelukast causes inhibition of airway cysteinyl leukotriene receptors as demonstrated by the ability to inhibit ...
  • Orally administered leukotriene-receptor antagonists (LRTAs), alone or with inhaled corticosteroids (ICSs), significantly improved asthma control and reduced exacerbations, according to a systematic review published online September 22 in the Annals of Internal Medicine . (medscape.com)
  • Cite this: Leukotriene-Receptor Antagonists Improve Asthma Control - Medscape - Sep 21, 2015. (medscape.com)
  • The leukotriene receptor antagonists are among the most prescribed drugs for the management of asthma, used both for treatment and prevention of acute asthmatic attacks. (nih.gov)
  • Two leukotriene receptor antagonists are available in the United States, zafirlukast (1996) and montelukast (1998). (nih.gov)
  • Review Pathophysiology of the cysteinyl leukotrienes and effects of leukotriene receptor antagonists in asthma. (nih.gov)
  • In two parallel, multicentre open-labelled pragmatic trials, Price and colleagues evaluated the effectiveness of inhaled corticosteroids (ICS) versus leukotriene receptor antagonists (LTRAs) as initial asthma therapy (in trial 1) and the addition of an LTRA or a long-acting β agonist (LABA), by random allocation, for participants who remained uncontrolled after 12 weeks of ICS (in trail 2). (bmj.com)
  • To determine whether pediatric asthmatic patients respond to inhaled corticosteroids (ICSs) and leukotriene receptor antagonists (LTRAs) similarly or if patients who do not respond to one medication respond to the other. (nih.gov)
  • Also known as leukotriene modifiers, leukotriene receptor antagonists work by decreasing the effects of an inflammatory chemical made by the body called leukotrienes. (healthychildren.org)
  • Montelukast is in a class of medications called leukotriene receptor antagonists (LTRAs). (medlineplus.gov)
  • Combinations with leukotriene receptor antagonists - R03DC. (whocc.no)
  • Patients were treated at our institution postop- eratively with topical mometasone (control group, N = 22), leukotriene-receptor-antagonists (montelukast [MT], N = 18) or underwent an aspirin desensitization (N = 21). (uni-muenchen.de)
  • Conclusion: Postoperative treatment with leukotriene-receptor-antagonists and aspi- rin desensitization both significantly reduce nasal polyp re- currence. (uni-muenchen.de)
  • Potent and selective antagonist of leukotriene D4 (LTD4) at the cysteinyl leukotriene receptor, CysLT1. (medscape.com)
  • Desloratadine is a long-acting tricyclic histamine antagonist that is selective for H 1 receptors. (medscape.com)
  • Levocetirizine is an H 1 -receptor antagonist, an active enantiomer of cetirizine. (medscape.com)
  • Histamine1-receptor antagonist. (medscape.com)
  • We here tested the hypothesis that leukotrienes are involved in the pathology of DLB and that blocking leukotrienes through Montelukast, a leukotriene receptor antagonist and approved anti-asthmatic drug, might alleviate pathology and restore cognitive functions. (nih.gov)
  • Can Leukotriene Receptor Antagonist Therapy Improve the Control of Patients with Severe Asthma on Biological Therapy and Coexisting Bronchiectasis? (uniba.it)
  • The aim of our study was to verify in this population the effect of leukotriene receptor antagonist (LTRA) therapy in clinical and inflammatory control before and after 6 months of introduction of biologic therapy. (uniba.it)
  • Choices at step 3: increase corticosteroid, add in beta- agonist or add in leukotriene receptor antagonist? (elsevierpure.com)
  • Overall, adding a long-acting beta-agonist to inhaled corticosteroids was significantly more likely (1.5 times) to be the best step-up therapy as compared to adding a leukotriene receptor antagonist to inhaled corticosteroids or to doubling inhaled corticosteroids. (nih.gov)
  • Nearly all the children responded differently to the three treatments, with 45 percent of children responding best to adding a long-acting beta-agonist, 28 percent responding best to adding leukotriene receptor antagonist, and 27 percent responding best to doubling the dose of inhaled corticosteroids. (nih.gov)
  • For example, African-American study participants were equally likely to respond best to long-acting beta-agonist step-up or inhaled corticosteroids step-up, and least likely to respond best to leukotriene receptor antagonist step-up. (nih.gov)
  • 16. Pharmacological characterization of the first potent and selective antagonist at the cysteinyl leukotriene 2 (CysLT(2)) receptor. (nih.gov)
  • Montelukast is a selective competitive inhibitor of the cysteinyl leukotriene receptor. (medscape.com)
  • Moreover, this work presents leukotriene signaling as a potential drug target for DLB and shows that Montelukast might be a promising drug candidate for future DLB therapy development. (nih.gov)
  • The two leukotriene modifiers currently in use, montelukast and zafirlukast, are very safe. (healthychildren.org)
  • The G protein-coupled cysteinyl leukotriene receptor CysLT 1 R mediates inflammatory processes and plays a major role in numerous disorders, including asthma, allergic rhinitis, cardiovascular disease, and cancer. (nih.gov)
  • This class of drugs acts by binding to cysteinyl leukotriene (CysLT) receptors and blocking their activation and the subsequent inflammatory cascade which cause the symptoms commonly associated with asthma and allergic rhinitis. (nih.gov)
  • These eicosanoids bind to CysLT receptors. (nih.gov)
  • The CysLT type-1 receptor is found in the human airway smooth muscle cells and airway macrophages and on other proinflammatory cells. (nih.gov)
  • Introduction: Asthma and bronchiectasis appear to be two related diseases and in their complex inflammatory interaction, the cysteinyl leukotriene/cysteinyl leukotriene receptor 1 (cysLT/cysLTR1) axis appears to play an important role given its involvement also in the neutrophilic pathway. (uniba.it)
  • To our knowledge, few studies have been conducted so far to evaluate the role of the leukotriene cysLT/cysLTr1 axis in the management of clinical and inflammatory outcomes within a population of patients with severe asthma and bronchiectasis. (uniba.it)
  • 3. Molecular cloning and functional characterization of murine cysteinyl-leukotriene 1 (CysLT(1)) receptors. (nih.gov)
  • 6. The molecular characterization and tissue distribution of the human cysteinyl leukotriene CysLT(2) receptor. (nih.gov)
  • 2. Identification in mice of two isoforms of the cysteinyl leukotriene 1 receptor that result from alternative splicing. (nih.gov)
  • 11. IL-5 up-regulates cysteinyl leukotriene 1 receptor expression in HL-60 cells differentiated into eosinophils. (nih.gov)
  • They include the following proteins: Leukotriene B4 receptors (BLTRs) - bind to and are activated by LTB4: BLT1 (Leukotriene B4 receptor 1) - LTB4R BLT2 (Leukotriene B4 receptor 2) - LTB4R2 Cysteinyl leukotriene receptors (CysLTRs) - bind to and are activated by LTC4, LTD4, and LTE4: CysLT1 (Cysteinyl leukotriene receptor 1) - CYSLTR1 CysLT2 (Cysteinyl leukotriene receptor 2) - CYSLTR2 The recently elucidated CysLTE, represented by GPR99/OXGR1, may constitute a third CysLTR. (wikipedia.org)
  • Characterization of the human cysteinyl leukotriene 2 receptor. (nih.gov)
  • 7. Molecular cloning and characterization of a second human cysteinyl leukotriene receptor: discovery of a subtype selective agonist. (nih.gov)
  • 9. Guinea pig cysteinyl leukotriene receptor 2 (gpCysLT2) mediates cell proliferation and intracellular calcium mobilization by LTC4 and LTD4. (nih.gov)
  • The cysteinyl leukotrienes LTC4, LTD4, and LTE4 are important mediators of human bronchial asthma. (rndsystems.com)
  • Review The role of leukotrienes in allergic rhinitis. (nih.gov)
  • 1. The murine cysteinyl leukotriene 2 (CysLT2) receptor. (nih.gov)
  • Pharmacologic studies have determined that cysteinyl leukotrienes activate at least 2 receptors, CysLTR1 and CysLTR2. (rndsystems.com)
  • Expression of cysteinyl leukotriene synthetic and signalling proteins in inflammatory cells in active seasonal allergic rhinitis. (nih.gov)
  • For instance, in May 2020, researchers from Chungbuk National University Hospital, South Korea, reported that NVP-1703 (a mixture of Bifidobacterium longum and Lactobacillus plantarum) treatment reduced urinary prostaglandin F2α and leukotriene E4 levels and therefore, NVP-1703 can be treatment option for perennial allergic rhinitis. (medgadget.com)
  • When a person is exposed again, the allergen triggers the antibodies to bind mast cells, and they release other inflammatory agents such as histamine and leukotrienes, which cause the runny noses, coughing, and watery eyes, collectively known as allergic rhinitis. (the-scientist.com)
  • These agents prevent or reverse some of the pathologic features associated with the inflammatory process mediated by leukotrienes. (medscape.com)
  • Prevents or reverses some of the pathologic features associated with the inflammatory process mediated by leukotrienes C4, D4, and E4. (medscape.com)
  • In asthmatic patients, leukotriene mediated effects include airway edema, smooth muscle contraction, and altered cellular activity associated with the inflammatory process. (nih.gov)
  • Prevent or reverse some of the pathologic features associated with the inflammatory process mediated by leukotrienes C 4 , D 4 , and E 4 . (medscape.com)
  • Migration of Th2 cells to the lung is key to their inflammatory function and is regulated in large part by chemokine receptors, members of the seven-membrane-spanning receptor family. (jci.org)
  • Inhibits release of histamine, leukotrienes, and other mediators from sensitized mast cells. (medscape.com)
  • Cysteinyl leukotrienes are potent lipid mediators in inflammation, inducing smooth muscle contractions and increased capillary permeability. (enzolifesciences.com)
  • Prior to randomization the following tests were collected: asthma history, allergen skin tests, blood total eosinophil counts , serum eosinophil cationic protein levels, serum total IgE levels, urinary leukotriene E4 levels, methacholine PC20 values, and exhaled nitric oxide levels were obtained. (nih.gov)
  • Singulair belongs to a group of drugs called leukotriene inhibitors which work by blocking leukotrienes, natural substances responsible for swelling in the airways, and tightening of muscles of airways, as well as nasal symptoms caused by allergies. (rxwiki.com)
  • Benralizumab (Fasenra TM ) is an interleukin-5 receptor alpha-directed cytolytic monoclonal antibody (IgG1, kappa) indicated for add-on maintenance treatment of individuals with severe asthma aged 12 years and older, and with an eosinophilic phenotype. (bcbsnd.com)
  • Inhibition of leukotriene synthesis impaired avoidance, but overall no single pathway interruption completely abrogated avoidance, indicating complex regulation. (nature.com)
  • Monoclonal antibody that inhibits IL-4 and IL-13 signaling by specifically binding to the IL-4 receptor-alpha subunit shared by the IL-4 and IL-13 receptor complexes. (medscape.com)
  • Blocking the IL-4 receptor-alpha subunit inhibits IL-4 and IL-13 cytokine-induced responses, including the release of proinflammatory cytokines, chemokines, and IgE. (medscape.com)
  • Loratadine selectively inhibits peripheral histamine H 1 receptors. (medscape.com)
  • They compete with histamine for histamine receptor type 1 (H1) receptor sites in the blood vessels, GI tract, and respiratory tract, which, in turn, inhibits physiologic effects that histamine normally induces at the H1 receptor sites. (medscape.com)
  • Selectively inhibits peripheral histamine H1 receptors. (medscape.com)
  • Of the genes affected by all three arsenicals, only one, that coding for interleukin-1 receptor, type II, showed enhanced expression, a finding confirmed by the reduced increase in NF-κB (nuclear factor kappa B) activity seen in response to interleukin-1β in iAs III -exposed cells. (nih.gov)
  • Eicosanoid receptor Oxoeicosanoid receptor Prostaglandin receptor Thromboxane receptor Kanaoka Y, Maekawa A, Austen KF (2013). (wikipedia.org)
  • 5-Oxo-ETE (EC50, 0.7nM) is a much more potent activator of actin polymerization in feline eosinophils than various other eicosanoids, including leukotriene (LT) B4 and prostaglandin D2. (nih.gov)
  • Cetirizine forms a complex with histamine for H 1 -receptor sites in blood vessels, the gastrointestinal (GI) tract, and the respiratory tract. (medscape.com)
  • First-generation antihistamines compete with histamine at the tissue-receptor level, preventing it from carrying out its mediator functions in urticaria. (medscape.com)
  • Journal Article] Biochemical characterization of three BLT receptors in zebrafish. (nii.ac.jp)
  • 5. Characterization of mouse cysteinyl leukotriene receptors mCysLT1 and mCysLT2: differential pharmacological properties and tissue distribution. (nih.gov)
  • A G-protein coupled receptor BLT2 is expressed in epithelial cells, and important in interstinal barrier function and epidermal wound healing. (nii.ac.jp)
  • Journal Article] 12-hydroxyheptadecatrienoic acid promotes epidermal wound healing by accelerating keratinocyte migration via the BLT2 receptor. (nii.ac.jp)
  • It has been reported recently that T cells lacking β-arrestin-2, a G protein-coupled receptor regulatory protein, demonstrate impaired migration in vitro. (jci.org)
  • Integrin alpha (ITGA)6 and 2 were enriched in several pathways, including focal adhesion and extracellular matrix‑receptor interaction. (spandidos-publications.com)
  • The cysteinyl leukotrienes (C4, D4 and E4) are products of arachidonic acid metabolism and are released from various cells, including mast cells and eosinophils. (nih.gov)
  • 13. An alternative pathway for metabolism of leukotriene D(4): effects on contractions to cysteinyl-leukotrienes in the guinea-pig trachea. (nih.gov)
  • Leukotrienes are major products of 5-lipoxygenase metabolism of arachidonic acid. (enzolifesciences.com)
  • Both receptors are members of the superfamily of G protein-coupled receptors. (rndsystems.com)
  • The action of peroxisome proliferators is thought to be mediated via specific receptors, called PPARs, which belong to the steroid hormone receptor superfamily. (joplink.net)
  • Participants must have had no corticosteroid treatment within 4 weeks, no leukotriene-modifying agents within 2 weeks, and no history of respiratory tract infection within 4 weeks of enrollment. (nih.gov)
  • Traditionally, drug therapy for allergy is based on the use of non-sedative antihistamines, i.e. blocking of the histamine H1 receptors, but sometimes additional help is obtained from blockers of the cysteinyl leukotriene receptor-1. (medindia.net)
  • In the near future, it is possible that drug therapy for allergy is a combination of H1 and H4 receptor blockers. (medindia.net)
  • People with allergies frequently take histamine and leukotriene blockers. (the-scientist.com)
  • Expression of 5-lipoxygenase, the rate-limiting enzyme for leukotriene production, was indeed elevated in brains with DLB. (nih.gov)
  • 17. Functional recognition of a distinct receptor preferential for leukotriene E4 in mice lacking the cysteinyl leukotriene 1 and 2 receptors. (nih.gov)
  • New drugs targeting the histamine H4 receptor are also undergoing clinical trials. (medindia.net)
  • Type 2 immune responses, notably involving interleukin (IL)-4, drive immunoglobulin class switch recombination to antigen-specific IgE, which is bound to the mast-cell-expressed high-affinity IgE receptor (FcεRI). (nature.com)
  • 2018. The allergen Der p3 from house dust mite stimulates store-operated Ca 2+ channels and mast cell migration through PAR4 receptors. (nih.gov)
  • The leukotriene (LT) receptors are G protein-coupled receptors that bind and are activated by the leukotrienes. (wikipedia.org)
  • Different drug molecules make it possible to affect the function of these receptors and, consequently, to prevent cell activation and mediator release. (medindia.net)
  • Fexofenadine competes with histamine for H 1 receptors in the GI tract, blood vessels, and the respiratory tract, reducing hypersensitivity reactions. (medscape.com)
  • Competes with histamine for H1 receptors in GI tract, blood vessels, and respiratory tract, reducing hypersensitivity reactions. (medscape.com)