Positively charged atoms, radicals or groups of atoms which travel to the cathode or negative pole during electrolysis.
Positively charged atoms, radicals or groups of atoms with a valence of plus 2, which travel to the cathode or negative pole during electrolysis.
Positively charged atoms, radicals or group of atoms with a valence of plus 1, which travel to the cathode or negative pole during electrolysis.
A family of proteins involved in the transport of organic cations. They play an important role in the elimination of a variety of endogenous substances, xenobiotics, and their metabolites from the body.
An organic cation transporter found in kidney. It is localized to the basal lateral membrane and is likely to be involved in the renal secretion of organic cations.
A metallic element that has the atomic symbol Mg, atomic number 12, and atomic weight 24.31. It is important for the activity of many enzymes, especially those involved in OXIDATIVE PHOSPHORYLATION.
A subgroup of TRP cation channels named after melastatin protein. They have the TRP domain but lack ANKYRIN repeats. Enzyme domains in the C-terminus leads to them being called chanzymes.
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.
A member of the alkali group of metals. It has the atomic symbol Na, atomic number 11, and atomic weight 23.
A subgroup of TRP cation channels that contain 3-4 ANKYRIN REPEAT DOMAINS and a conserved C-terminal domain. Members are highly expressed in the CENTRAL NERVOUS SYSTEM. Selectivity for calcium over sodium ranges from 0.5 to 10.
Gated, ion-selective glycoproteins that traverse membranes. The stimulus for ION CHANNEL GATING can be due to a variety of stimuli such as LIGANDS, a TRANSMEMBRANE POTENTIAL DIFFERENCE, mechanical deformation or through INTRACELLULAR SIGNALING PEPTIDES AND PROTEINS.
An element in the alkali group of metals with an atomic symbol K, atomic number 19, and atomic weight 39.10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the WATER-ELECTROLYTE BALANCE.
A trace element with atomic symbol Mn, atomic number 25, and atomic weight 54.94. It is concentrated in cell mitochondria, mostly in the pituitary gland, liver, pancreas, kidney, and bone, influences the synthesis of mucopolysaccharides, stimulates hepatic synthesis of cholesterol and fatty acids, and is a cofactor in many enzymes, including arginase and alkaline phosphatase in the liver. (From AMA Drug Evaluations Annual 1992, p2035)
Membrane proteins whose primary function is to facilitate the transport of positively charged molecules (cations) across a biological membrane.
The rate dynamics in chemical or physical systems.
The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
The voltage differences across a membrane. For cellular membranes they are computed by subtracting the voltage measured outside the membrane from the voltage measured inside the membrane. They result from differences of inside versus outside concentration of potassium, sodium, chloride, and other ions across cells' or ORGANELLES membranes. For excitable cells, the resting membrane potentials range between -30 and -100 millivolts. Physical, chemical, or electrical stimuli can make a membrane potential more negative (hyperpolarization), or less negative (depolarization).
An element that is an alkali metal. It has an atomic symbol Rb, atomic number 37, and atomic weight 85.47. It is used as a chemical reagent and in the manufacture of photoelectric cells.
An element of the alkaline earth family of metals. It has the atomic symbol Sr, atomic number 38, and atomic weight 87.62.
An element in the alkali metals family. It has the atomic symbol Li, atomic number 3, and atomic weight [6.938; 6.997]. Salts of lithium are used in treating BIPOLAR DISORDER.
A subgroup of TRP cation channels named after vanilloid receptor. They are very sensitive to TEMPERATURE and hot spicy food and CAPSAICIN. They have the TRP domain and ANKYRIN repeats. Selectivity for CALCIUM over SODIUM ranges from 3 to 100 fold.
High molecular weight insoluble polymers which contain functional anionic groups that are capable of undergoing exchange reactions with cations.
A member of the alkali metals. It has an atomic symbol Cs, atomic number 50, and atomic weight 132.91. Cesium has many industrial applications, including the construction of atomic clocks based on its atomic vibrational frequency.
Metals that constitute group 1(formerly group Ia) of the periodic table. They are the most strongly electropositive of the metals. Note that HYDROGEN is not considered an alkali metal even though it falls under the group 1 heading in the periodic table.
The movement of ions across energy-transducing cell membranes. Transport can be active, passive or facilitated. Ions may travel by themselves (uniport), or as a group of two or more ions in the same (symport) or opposite (antiport) directions.
A quality of cell membranes which permits the passage of solvents and solutes into and out of cells.
A subgroup of cyclic nucleotide-regulated ION CHANNELS within the superfamily of pore-loop cation channels. They are expressed in OLFACTORY NERVE cilia and in PHOTORECEPTOR CELLS and some PLANTS.
An element of the alkaline earth group of metals. It has an atomic symbol Ba, atomic number 56, and atomic weight 138. All of its acid-soluble salts are poisonous.
An atom or group of atoms that have a positive or negative electric charge due to a gain (negative charge) or loss (positive charge) of one or more electrons. Atoms with a positive charge are known as CATIONS; those with a negative charge are ANIONS.
The opening and closing of ion channels due to a stimulus. The stimulus can be a change in membrane potential (voltage-gated), drugs or chemical transmitters (ligand-gated), or a mechanical deformation. Gating is thought to involve conformational changes of the ion channel which alters selective permeability.
An electrophysiologic technique for studying cells, cell membranes, and occasionally isolated organelles. All patch-clamp methods rely on a very high-resistance seal between a micropipette and a membrane; the seal is usually attained by gentle suction. The four most common variants include on-cell patch, inside-out patch, outside-out patch, and whole-cell clamp. Patch-clamp methods are commonly used to voltage clamp, that is control the voltage across the membrane and measure current flow, but current-clamp methods, in which the current is controlled and the voltage is measured, are also used.
Derivatives of ammonium compounds, NH4+ Y-, in which all four of the hydrogens bonded to nitrogen have been replaced with hydrocarbyl groups. These are distinguished from IMINES which are RN=CR2.
A chelating agent that sequesters a variety of polyvalent cations such as CALCIUM. It is used in pharmaceutical manufacturing and as a food additive.
The ability of a substrate to allow the passage of ELECTRONS.
The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.
An anthranilic acid derivative with analgesic, anti-inflammatory, and antipyretic properties. It is used in musculoskeletal and joint disorders and administered by mouth and topically. (From Martindale, The Extra Pharmacopoeia, 30th ed, p16)
Electropositive chemical elements characterized by ductility, malleability, luster, and conductance of heat and electricity. They can replace the hydrogen of an acid and form bases with hydroxyl radicals. (Grant & Hackh's Chemical Dictionary, 5th ed)
Voltage-dependent cell membrane glycoproteins selectively permeable to calcium ions. They are categorized as L-, T-, N-, P-, Q-, and R-types based on the activation and inactivation kinetics, ion specificity, and sensitivity to drugs and toxins. The L- and T-types are present throughout the cardiovascular and central nervous systems and the N-, P-, Q-, & R-types are located in neuronal tissue.
The parts of a macromolecule that directly participate in its specific combination with another molecule.
Lanthanum. The prototypical element in the rare earth family of metals. It has the atomic symbol La, atomic number 57, and atomic weight 138.91. Lanthanide ion is used in experimental biology as a calcium antagonist; lanthanum oxide improves the optical properties of glass.
A trace element that is a component of vitamin B12. It has the atomic symbol Co, atomic number 27, and atomic weight 58.93. It is used in nuclear weapons, alloys, and pigments. Deficiency in animals leads to anemia; its excess in humans can lead to erythrocytosis.
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.
Inorganic compounds derived from hydrochloric acid that contain the Cl- ion.
An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter.
The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.
A potassium-selective ion channel blocker. (From J Gen Phys 1994;104(1):173-90)
A metallic element of atomic number 30 and atomic weight 65.38. It is a necessary trace element in the diet, forming an essential part of many enzymes, and playing an important role in protein synthesis and in cell division. Zinc deficiency is associated with ANEMIA, short stature, HYPOGONADISM, impaired WOUND HEALING, and geophagia. It is known by the symbol Zn.
A group of membrane transport proteins that transport biogenic amine derivatives of catechol across the PLASMA MEMBRANE. Catecholamine plasma membrane transporter proteins regulate neural transmission as well as catecholamine metabolism and recycling.
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.
The movement of materials across cell membranes and epithelial layers against an electrochemical gradient, requiring the expenditure of metabolic energy.
The concentration of osmotically active particles in solution expressed in terms of osmoles of solute per liter of solution. Osmolality is expressed in terms of osmoles of solute per kilogram of solvent.
The study of the generation and behavior of electrical charges in living organisms particularly the nervous system and the effects of electricity on living organisms.
A trace element with the atomic symbol Ni, atomic number 28, and atomic weight 58.69. It is a cofactor of the enzyme UREASE.
Substances produced from the reaction between acids and bases; compounds consisting of a metal (positive) and nonmetal (negative) radical. (Grant & Hackh's Chemical Dictionary, 5th ed)
Gadolinium. An element of the rare earth family of metals. It has the atomic symbol Gd, atomic number 64, and atomic weight 157.25. Its oxide is used in the control rods of some nuclear reactors.
The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
A subgroup of TRP cation channels that are widely expressed in various cell types. Defects are associated with POLYCYSTIC KIDNEY DISEASES.
Membrane transporters that co-transport two or more dissimilar molecules in the opposite direction across a membrane. Usually the transport of one ion or molecule is against its electrochemical gradient and is "powered" by the movement of another ion or molecule with its electrochemical gradient.
A chelating agent relatively more specific for calcium and less toxic than EDETIC ACID.
An enzyme that catalyzes the active transport system of sodium and potassium ions across the cell wall. Sodium and potassium ions are closely coupled with membrane ATPase which undergoes phosphorylation and dephosphorylation, thereby providing energy for transport of these ions against concentration gradients.
A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.
An element with atomic symbol Cd, atomic number 48, and atomic weight 114. It is a metal and ingestion will lead to CADMIUM POISONING.
A group of elements that include SCANDIUM; YTTRIUM; and the LANTHANOID SERIES ELEMENTS. Historically, the rare earth metals got their name from the fact that they were never found in their pure elemental form, but as an oxide. In addition they were very difficult to purify. They are not truly rare and comprise about 25% of the metals in the earth's crust.
Metals that constitute the group 2 (formerly group IIa) of the periodic table.
Property of membranes and other structures to permit passage of light, heat, gases, liquids, metabolites, and mineral ions.
A cardioactive glycoside consisting of rhamnose and ouabagenin, obtained from the seeds of Strophanthus gratus and other plants of the Apocynaceae; used like DIGITALIS. It is commonly used in cell biological studies as an inhibitor of the NA(+)-K(+)-EXCHANGING ATPASE.
A ubiquitous sodium salt that is commonly used to season food.
A white crystal or crystalline powder used in BUFFERS; FERTILIZERS; and EXPLOSIVES. It can be used to replenish ELECTROLYTES and restore WATER-ELECTROLYTE BALANCE in treating HYPOKALEMIA.
A heavy, bluish white metal, atomic number 81, atomic weight [204.382; 204.385], symbol Tl.
Female germ cells derived from OOGONIA and termed OOCYTES when they enter MEIOSIS. The primary oocytes begin meiosis but are arrested at the diplotene state until OVULATION at PUBERTY to give rise to haploid secondary oocytes or ova (OVUM).
A salt used to replenish calcium levels, as an acid-producing diuretic, and as an antidote for magnesium poisoning.
An organic amine proton acceptor. It is used in the synthesis of surface-active agents and pharmaceuticals; as an emulsifying agent for cosmetic creams and lotions, mineral oil and paraffin wax emulsions, as a biological buffer, and used as an alkalizer. (From Merck, 11th ed; Martindale, The Extra Pharmacopoeia, 30th ed, p1424)
Stable elementary particles having the smallest known positive charge, found in the nuclei of all elements. The proton mass is less than that of a neutron. A proton is the nucleus of the light hydrogen atom, i.e., the hydrogen ion.
Established cell cultures that have the potential to propagate indefinitely.
Chemicals that bind to and remove ions from solutions. Many chelating agents function through the formation of COORDINATION COMPLEXES with METALS.
Reversible chemical reaction between a solid, often one of the ION EXCHANGE RESINS, and a fluid whereby ions may be exchanged from one substance to another. This technique is used in water purification, in research, and in industry.
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
A broad group of eukaryotic six-transmembrane cation channels that are classified by sequence homology because their functional involvement with SENSATION is varied. They have only weak voltage sensitivity and ion selectivity. They are named after a DROSOPHILA mutant that displayed transient receptor potentials in response to light. A 25-amino-acid motif containing a TRP box (EWKFAR) just C-terminal to S6 is found in TRPC, TRPV and TRPM subgroups. ANKYRIN repeats are found in TRPC, TRPV & TRPN subgroups. Some are functionally associated with TYROSINE KINASE or TYPE C PHOSPHOLIPASES.
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 process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.
An active neurotoxic metabolite of 1-METHYL-4-PHENYL-1,2,3,6-TETRAHYDROPYRIDINE. The compound reduces dopamine levels, inhibits the biosynthesis of catecholamines, depletes cardiac norepinephrine and inactivates tyrosine hydroxylase. These and other toxic effects lead to cessation of oxidative phosphorylation, ATP depletion, and cell death. The compound, which is related to PARAQUAT, has also been used as an herbicide.
A group of peptide antibiotics from BACILLUS brevis. Gramicidin C or S is a cyclic, ten-amino acid polypeptide and gramicidins A, B, D are linear. Gramicidin is one of the two principal components of TYROTHRICIN.
Cell membrane glycoproteins that are selectively permeable to potassium ions. At least eight major groups of K channels exist and they are made up of dozens of different subunits.
The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).
Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.
A cyclododecadepsipeptide ionophore antibiotic produced by Streptomyces fulvissimus and related to the enniatins. It is composed of 3 moles each of L-valine, D-alpha-hydroxyisovaleric acid, D-valine, and L-lactic acid linked alternately to form a 36-membered ring. (From Merck Index, 11th ed) Valinomycin is a potassium selective ionophore and is commonly used as a tool in biochemical studies.
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.
Transport proteins that carry specific substances in the blood or across cell membranes.
A pyrazine compound inhibiting SODIUM reabsorption through SODIUM CHANNELS in renal EPITHELIAL CELLS. This inhibition creates a negative potential in the luminal membranes of principal cells, located in the distal convoluted tubule and collecting duct. Negative potential reduces secretion of potassium and hydrogen ions. Amiloride is used in conjunction with DIURETICS to spare POTASSIUM loss. (From Gilman et al., Goodman and Gilman's The Pharmacological Basis of Therapeutics, 9th ed, p705)
A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
The study of chemical changes resulting from electrical action and electrical activity resulting from chemical changes.
The relationship between the dose of an administered drug and the response of the organism to the drug.
Stable cesium atoms that have the same atomic number as the element cesium, but differ in atomic weight. Cs-133 is a naturally occurring isotope.
Ions with the suffix -onium, indicating cations with coordination number 4 of the type RxA+ which are analogous to QUATERNARY AMMONIUM COMPOUNDS (H4N+). Ions include phosphonium R4P+, oxonium R3O+, sulfonium R3S+, chloronium R2Cl+
The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.
Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.
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.
Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.
Layers of lipid molecules which are two molecules thick. Bilayer systems are frequently studied as models of biological membranes.
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
A subgroup of cyclic nucleotide-regulated ION CHANNELS of the superfamily of pore-loop cation channels that are opened by hyperpolarization rather than depolarization. The ion conducting pore passes SODIUM, CALCIUM, and POTASSIUM cations with a preference for potassium.
Proteins prepared by recombinant DNA technology.
Ion channels that specifically allow the passage of SODIUM ions. A variety of specific sodium channel subtypes are involved in serving specialized functions such as neuronal signaling, CARDIAC MUSCLE contraction, and KIDNEY function.
A polyamine formed from putrescine. It is found in almost all tissues in association with nucleic acids. It is found as a cation at all pH values, and is thought to help stabilize some membranes and nucleic acid structures. It is a precursor of spermine.
The accumulation of an electric charge on a object
A group of enzymes which catalyze the hydrolysis of ATP. The hydrolysis reaction is usually coupled with another function such as transporting Ca(2+) across a membrane. These enzymes may be dependent on Ca(2+), Mg(2+), anions, H+, or DNA.
A class of sodium-independent nucleoside transporters that mediate the facilitative transport of NUCLEOSIDES.
Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
Measurement of the intensity and quality of fluorescence.
A biogenic polyamine formed from spermidine. It is found in a wide variety of organisms and tissues and is an essential growth factor in some bacteria. It is found as a polycation at all pH values. Spermine is associated with nucleic acids, particularly in viruses, and is thought to stabilize the helical structure.
Separation technique in which the stationary phase consists of ion exchange resins. The resins contain loosely held small ions that easily exchange places with other small ions of like charge present in solutions washed over the resins.
A basic constituent of lecithin that is found in many plants and animal organs. It is important as a precursor of acetylcholine, as a methyl donor in various metabolic processes, and in lipid metabolism.
The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.
Organic compounds that contain phosphorus as an integral part of the molecule. Included under this heading is broad array of synthetic compounds that are used as PESTICIDES and DRUGS.
The physical characteristics and processes of biological systems.
The study of PHYSICAL PHENOMENA and PHYSICAL PROCESSES as applied to living things.
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.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
A class of drugs that act by selective inhibition of calcium influx through cellular membranes.
The sum of the weight of all the atoms in a molecule.
Cationic ionophore antibiotic obtained from Streptomyces lasaliensis that, among other effects, dissociates the calcium fluxes in muscle fibers. It is used as a coccidiostat, especially in poultry.
An anionic compound that is used as a reagent for determination of potassium, ammonium, rubidium, and cesium ions. It also uncouples oxidative phosphorylation and forms complexes with biological materials, and is used in biological assays.
Elements of limited time intervals, contributing to particular results or situations.
Interstitial space between cells, occupied by INTERSTITIAL FLUID as well as amorphous and fibrous substances. For organisms with a CELL WALL, the extracellular space includes everything outside of the CELL MEMBRANE including the PERIPLASM and the cell wall.
A purinergic P2X neurotransmitter receptor that plays a role in pain sensation signaling and regulation of inflammatory processes.
The interaction of two or more substrates or ligands with the same binding site. The displacement of one by the other is used in quantitative and selective affinity measurements.
A colloidal, hydrated aluminum silicate that swells 12 times its dry size when added to water.
Inorganic or organic oxy acids of sulfur which contain the RSO2(OH) radical.
1-Deoxy-1-(methylamino)-D-glucitol. A derivative of sorbitol in which the hydroxyl group in position 1 is replaced by a methylamino group. Often used in conjunction with iodinated organic compounds as contrast medium.
Stable potassium atoms that have the same atomic number as the element potassium, but differ in atomic weight. K-41 is a stable potassium isotope.
Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).
The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Stable sodium atoms that have the same atomic number as the element sodium, but differ in atomic weight. Na-23 is a stable sodium isotope.
Agents that emit light after excitation by light. The wave length of the emitted light is usually longer than that of the incident light. Fluorochromes are substances that cause fluorescence in other substances, i.e., dyes used to mark or label other compounds with fluorescent tags.
Membrane proteins that allow the exchange of hydrogen ions for potassium ions across the cellular membrane. The action of these antiporters influences intracellular pH and potassium ion homeostasis.
High molecular weight, insoluble polymers which contain functional groups that are capable of undergoing exchange reactions (ION EXCHANGE) with either cations or anions.
A chemical system that functions to control the levels of specific ions in solution. When the level of hydrogen ion in solution is controlled the system is called a pH buffer.
An aquatic genus of the family, Pipidae, occurring in Africa and distinguished by having black horny claws on three inner hind toes.
The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.
A polyether antibiotic which affects ion transport and ATPase activity in mitochondria. It is produced by Streptomyces hygroscopicus. (From Merck Index, 11th ed)
Inorganic salts of phosphoric acid.
A class of cell surface receptors for PURINES that prefer ATP or ADP over ADENOSINE. P2 purinergic receptors are widespread in the periphery and in the central and peripheral nervous system.
A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).
Genetically engineered MUTAGENESIS at a specific site in the DNA molecule that introduces a base substitution, or an insertion or deletion.
The spatial arrangement of the atoms of a nucleic acid or polynucleotide that results in its characteristic 3-dimensional shape.
Salts of hydrobromic acid, HBr, with the bromine atom in the 1- oxidation state. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
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 disaccharide consisting of one galactose and one glucose moiety in an alpha (1-6) glycosidic linkage.
The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.
Hemolytic anemia due to various intrinsic defects of the erythrocyte.
Highly reactive molecules with an unsatisfied electron valence pair. Free radicals are produced in both normal and pathological processes. They are proven or suspected agents of tissue damage in a wide variety of circumstances including radiation, damage from environment chemicals, and aging. Natural and pharmacological prevention of free radical damage is being actively investigated.
The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.
An inorganic dye used in microscopy for differential staining and as a diagnostic reagent. In research this compound is used to study changes in cytoplasmic concentrations of calcium. Ruthenium red inhibits calcium transport through membrane channels.
A widely distributed purinergic P2X receptor subtype that plays a role in pain sensation. P2X4 receptors found on MICROGLIA cells may also play a role in the mediation of allodynia-related NEUROPATHIC PAIN.
Contractile tissue that produces movement in animals.
The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.
A silver metallic element that exists as a liquid at room temperature. It has the atomic symbol Hg (from hydrargyrum, liquid silver), atomic number 80, and atomic weight 200.59. Mercury is used in many industrial applications and its salts have been employed therapeutically as purgatives, antisyphilitics, disinfectants, and astringents. It can be absorbed through the skin and mucous membranes which leads to MERCURY POISONING. Because of its toxicity, the clinical use of mercury and mercurials is diminishing.
The first chemical element in the periodic table. It has the atomic symbol H, atomic number 1, and atomic weight [1.00784; 1.00811]. It exists, under normal conditions, as a colorless, odorless, tasteless, diatomic gas. Hydrogen ions are PROTONS. Besides the common H1 isotope, hydrogen exists as the stable isotope DEUTERIUM and the unstable, radioactive isotope TRITIUM.
A fluorescent calcium chelating agent which is used to study intracellular calcium in tissues.
Proteins found in any species of bacterium.
A family of proton-gated sodium channels that are primarily expressed in neuronal tissue. They are AMILORIDE-sensitive and are implicated in the signaling of a variety of neurological stimuli, most notably that of pain in response to acidic conditions.
The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.
A general class of integral membrane proteins that transport ions across a membrane against an electrochemical gradient.
The facilitation of a chemical reaction by material (catalyst) that is not consumed by the reaction.
Terbium. An element of the rare earth family of metals. It has the atomic symbol Tb, atomic number 65, and atomic weight 158.92.
Signal transduction mechanisms whereby calcium mobilization (from outside the cell or from intracellular storage pools) to the cytoplasm is triggered by external stimuli. Calcium signals are often seen to propagate as waves, oscillations, spikes, sparks, or puffs. The calcium acts as an intracellular messenger by activating calcium-responsive proteins.
A constituent of STRIATED MUSCLE and LIVER. It is an amino acid derivative and an essential cofactor for fatty acid metabolism.
Artificially produced membranes, such as semipermeable membranes used in artificial kidney dialysis (RENAL DIALYSIS), monomolecular and bimolecular membranes used as models to simulate biological CELL MEMBRANES. These membranes are also used in the process of GUIDED TISSUE REGENERATION.
An inhibitor of anion conductance including band 3-mediated anion transport.
The homogeneous mixtures formed by the mixing of a solid, liquid, or gaseous substance (solute) with a liquid (the solvent), from which the dissolved substances can be recovered by physical processes. (From Grant & Hackh's Chemical Dictionary, 5th ed)
Unstable isotopes of sodium that decay or disintegrate emitting radiation. Na atoms with atomic weights 20-22 and 24-26 are radioactive sodium isotopes.
A plasma membrane exchange glycoprotein transporter that functions in intracellular pH regulation, cell volume regulation, and cellular response to many different hormones and mitogens.
Silver. An element with the atomic symbol Ag, atomic number 47, and atomic weight 107.87. It is a soft metal that is used medically in surgical instruments, dental prostheses, and alloys. Long-continued use of silver salts can lead to a form of poisoning known as ARGYRIA.
Unstable isotopes of rubidium that decay or disintegrate emitting radiation. Rb atoms with atomic weights 79-84, and 86-95 are radioactive rubidium isotopes.
Phenolic metacyclophanes derived from condensation of PHENOLS and ALDEHYDES. The name derives from the vase-like molecular structures. A bracketed [n] indicates the number of aromatic rings.
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 sesquiterpene lactone found in roots of THAPSIA. It inhibits CA(2+)-TRANSPORTING ATPASE mediated uptake of CALCIUM into SARCOPLASMIC RETICULUM.
The study of crystal structure using X-RAY DIFFRACTION techniques. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
The process of cleaving a chemical compound by the addition of a molecule of water.
Substances that dissociate into two or more ions, to some extent, in water. Solutions of electrolytes thus conduct an electric current and can be decomposed by it (ELECTROLYSIS). (Grant & Hackh's Chemical Dictionary, 5th ed)
A subclass of purinergic P2 receptors that signal by means of a ligand-gated ion channel. They are comprised of three P2X subunits which can be identical (homotrimeric form) or dissimilar (heterotrimeric form).
A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).
Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.
The characteristic three-dimensional shape of a molecule.

The contribution of adjacent subunits to the active sites of D-3-phosphoglycerate dehydrogenase. (1/3963)

D-3-Phosphoglycerate dehydrogenase (PGDH) from Escherichia coli is allosterically inhibited by L-serine, the end product of its metabolic pathway. Previous results have shown that inhibition by serine has a large effect on Vmax and only a small or negligible effect on Km. PGDH is thus classified as a V-type allosteric enzyme. In this study, the active site of PGDH has been studied by site-directed mutagenesis to assess the role of certain residues in substrate binding and catalysis. These consist of a group of cationic residues (Arg-240, Arg-60, Arg-62, Lys-39, and Lys-141') that potentially form an electrostatic environment for the binding of the negatively charged substrate, as well as the only tryptophan residue found in PGDH and which fits into a hydrophobic pocket immediately adjacent to the active site histidine residue. Interestingly, Trp-139' and Lys-141' are part of the polypeptide chain of the subunit that is adjacent to the active site. The results of mutating these residues show that Arg-240, Arg-60, Arg-62, and Lys-141' play distinct roles in the binding of the substrate to the active site. Mutants of Trp-139' show that this residue may play a role in stabilizing the catalytic center of the enzyme. Furthermore, these mutants appear to have a significant effect on the cooperativity of serine inhibition and suggest a possible role for Trp-139' in the cooperative interactions between subunits.  (+info)

The stimulatory effects of Hofmeister ions on the activities of neuronal nitric-oxide synthase. Apparent substrate inhibition by l-arginine is overcome in the presence of protein-destabilizing agents. (2/3963)

A variety of monovalent anions and cations were effective in stimulating both calcium ion/calmodulin (Ca2+/CaM)-independent NADPH-cytochrome c reductase activity of, and Ca2+/CaM-dependent nitric oxide (NO.) synthesis by, neuronal nitric oxide synthase (nNOS). The efficacy of the ions in stimulating both activities could be correlated, in general, with their efficacy in precipitating or stabilizing certain proteins, an order referred to as the Hofmeister ion series. In the hemoglobin capture assay, used for measurement of NO. production, apparent substrate inhibition by L-arginine was almost completely reversed by the addition of sodium perchlorate (NaClO4), one of the more effective protein-destabilizing agents tested. Examination of this phenomenon by the assay of L-arginine conversion to L-citrulline revealed that the stimulatory effect of NaClO4 on the reaction was observed only in the presence of oxyhemoglobin or superoxide anion (generated by xanthine and xanthine oxidase), both scavengers of NO. Spectrophotometric examination of nNOS revealed that the addition of NaClO4 and a superoxide-generating system, but neither alone, prevented the increase of heme absorption at 436 nm, which has been attributed to the nitrosyl complex. The data are consistent with the release of autoinhibitory NO. coordinated to the prosthetic group of nNOS, which, in conjunction with an NO. scavenger, causes stimulation of the reaction.  (+info)

Screening for mutations of the cationic trypsinogen gene: are they of relevance in chronic alcoholic pancreatitis? (3/3963)

BACKGROUND: In hereditary pancreatitis mutations of exons 2 (N21I) and 3 (R117H) of the cationic trypsinogen gene have been described. AIMS: To investigate whether the same mutations can also be found in patients with chronic alcoholic pancreatitis. METHODS: Leucocyte DNA was prepared from 23 patients with chronic alcoholic pancreatitis, 21 with alcoholic liver cirrhosis, 34 individuals from seven independent families with hereditary pancreatitis, and 15 healthy controls. DNA was also obtained from pancreatic tissue (n=7) and from pancreatic juice (n=5) of patients suffering from chronic alcoholic pancreatitis. R117H was detected by restriction digestion with Afl III. N21I was identified by an allele specific polymerase chain reaction (PCR). RESULTS: R117H was detected in four families with hereditary pancreatitis. The N21I mutation was identified in three families. All mutations were confirmed by sequencing of the corresponding DNAs. In patients with chronic alcoholic pancreatitis neither the exon 2 nor exon 3 mutations were present in blood leucocytes, pancreatic juice, or pancreatic tissue. DNA of the patients with alcoholic liver cirrhosis as well as all controls was of wild type. CONCLUSIONS: The allele specific PCR may be used to screen for the N21I mutation of cationic trypsinogen. Both trypsinogen mutations were found in hereditary pancreatitis but do not seem to be major pathogenic factors in chronic alcoholic pancreatitis.  (+info)

Location of a cation-binding site in the loop between helices F and G of bacteriorhodopsin as studied by 13C NMR. (4/3963)

The high-affinity cation-binding sites of bacteriorhodopsin (bR) were examined by solid-state 13C NMR of samples labeled with [3-13C]Ala and [1-13C]Val. We found that the 13C NMR spectra of two kinds of blue membranes, deionized (pH 4) and acid blue at pH 1.2, were very similar and different from that of the native purple membrane. This suggested that when the surface pH is lowered, either by removal of cations or by lowering the bulk pH, substantial change is induced in the secondary structure of the protein. Partial replacement of the bound cations with Na+, Ca2+, or Mn2+ produced additional spectral changes in the 13C NMR spectra. The following conclusions were made. First, there are high-affinity cation-binding sites in both the extracellular and the cytoplasmic regions, presumably near the surface, and one of the preferred cation-binding sites is located at the loop between the helix F and G (F-G loop) near Ala196, consistent with the 3D structure of bR from x-ray diffraction and cryoelectron microscopy. Second, the bound cations undergo rather rapid exchange (with a lifetime shorter than 3 ms) among various types of cation-binding sites. As expected from the location of one of the binding sites, cation binding induced conformational alteration of the F-G interhelical loop.  (+info)

Modulation of slow inactivation in human cardiac Kv1.5 channels by extra- and intracellular permeant cations. (5/3963)

1. The properties and regulation of slow inactivation by intracellular and extracellular cations in the human heart K+ channel hKv1.5 have been investigated. Extensive NH2- and COOH-terminal deletions outside the central core of transmembrane domains did not affect the degree of inactivation. 2. The voltage dependence of steady-state inactivation curves of hKv1.5 channels was unchanged in Rb+ and Cs+, compared with K+, but biexponential inactivation over 10 s was reduced from approximately 100 % of peak current in Na+ to approximately 65 % in K+, approximately 50 % in Rb+ and approximately 30 % in Cs+. This occurred as a result of a decrease in both fast and slow components of inactivation, with little change in inactivation time constants. 3. Changes in extracellular cation species and concentration (5-300 mM) had only small effects on the rates of inactivation and recovery from inactivation (tau recovery approximately 1 s). Mutation of residues at a putative regulatory site at R487 in the outer pore mouth did not affect slow inactivation or recovery from inactivation of hKv1.5, although sensitivity to extracellular TEA was conferred. 4. Symmetrical reduction of both intra- and extracellular cation concentrations accelerated and augmented both components of inactivation of K+ (Kd = 34.7 mM) and Cs+ (Kd = 20.5 mM) currents. These effects could be quantitatively accounted for by unilateral reduction of intracellular K+ (K+i) (Kd = 43.4 mM) or Cs+i with constant 135 mM external ion concentrations. 5. We conclude that inactivation and recovery from inactivation in hKv1.5 were not typically C-type in nature. However, the ion species dependence of inactivation was still closely coupled to ion permeation through the pore. Intracellular ion modulatory actions were more potent than extracellular actions, although still of relatively low affinity. These results suggest the presence of ion binding sites capable of regulating inactivation located on both intracellular and extracellular sides of the pore selectivity filter.  (+info)

Gating current studies reveal both intra- and extracellular cation modulation of K+ channel deactivation. (6/3963)

1. The presence of permeant ions can modulate the rate of gating charge return in wild-type human heart K+ (hKv1.5) channels. Here we employ gating current measurements in a non-conducting mutant, W472F, of the hKv1.5 channel to investigate how different cations can modulate charge return and whether the actions can be specifically localized at the internal as well as the external mouth of the channel pore. 2. Intracellular cations were effective at accelerating charge return in the sequence Cs+ > Rb+ > K+ > Na+ > NMG+. Extracellular cations accelerated charge return with the selectivity sequence Cs+ > Rb+ > Na+ = NMG+. 3. Intracellular and extracellular cation actions were of relatively low affinity. The Kd for preventing slowing of the time constant of the off-gating current decay (tau off) was 20.2 mM for intracellular Cs+ (Cs+i) and 358 mM for extracellular Cs+ (Cs+o). 4. Both intracellular and extracellular cations can regulate the rate of charge return during deactivation of hKv1.5, but intracellular cations are more effective. We suggest that ion crystal radius is an important determinant of this action, with larger ions preventing slowing more effectively. Important parallels exist with cation-dependent modulation of slow inactivation of ionic currents in this channel. However, further experiments are required to understand the exact relationship between acceleration of charge return and the slowing of inactivation of ionic currents by cations.  (+info)

Phospholipid-subclass-specific partitioning of lipophilic ions in membrane-water systems. (7/3963)

Herein, we systematically investigate phospholipid-subclass-specific alterations in the partitioning of both cationic and anionic amphiphiles to identify the importance of ester, ether and vinyl ether linkages at the sn-1 position of phospholipids in the partitioning of charged amphiphiles. The results demonstrated that the membrane-water partition coefficient of a prototypic cationic amphiphile (i.e. 3,3'-dipropylthiadicarbocyanine iodide) was approximately 2.5 times higher in membranes comprised of plasmenylcholine in comparison with membranes comprised of either phosphatidylcholine or plasmanylcholine. In striking contrast, the membrane-water partition coefficient of a prototypic anionic amphiphile [i.e. bis-(1,3-dibutylbarbituric acid)trimethine oxonol] in membranes comprised of plasmenylcholine was approximately 2.5 times lower than that manifest in membranes comprised of phosphatidylcholine or plasmanylcholine. Utilizing theseexperimentally determined partition coefficients,the relative membrane dipole potential of membranes comprised of plasmenylcholine was calculated and found to be approximately 25 mV lower than in membranes comprised of phosphatidylcholine or plasmanylcholine. This lower membrane dipole potential in membranes comprised of plasmenylcholine is equivalent to the membrane potential induced by incorporation of approximately 25 mol% of anionic phospholipids in membranes comprised of phosphatidylcholine. Collectively, these results demonstrate that phospholipid-subclass-specific differences in the membrane dipole potential contribute to alterations in the partitioning of lipophilic ions in membrane bilayers comprised of distinct phospholipid subclasses. Moreover, they suggest that these physicochemical differences can be exploited to facilitate the targeting of charged lipophilic drugs to specific cells and subcellular membrane compartments.  (+info)

Partitioning of triphenylalkylphosphonium homologues in gel bead-immobilized liposomes: chromatographic measurement of their membrane partition coefficients. (8/3963)

Unilamellar liposomes of small or large size, SUVs and LUVs, respectively, were stably immobilized in the highly hydrophilic Sepharose 4B or Sephacryl S-1000 gel beads as a membrane stationary phase for immobilized liposome chromatography (ILC). Lipophilic cations of triphenylmethylphosphonium and tetraphenylphosphonium (TPP+) have been used as probes of the membrane potential of cells. Interaction of TPP+ and triphenylalkylphosphonium homologues with the immobilized liposomal membranes was shown by their elution profiles on both zonal and frontal ILC. Retardation of the lipophilic cations on the liposome gel bed was increased as the hydrophobicity of the cations increased, indicating the partitioning of lipophilic cations into the hydrocarbon region of the membranes. The cations did not retard on the Sepharose or Sephacryl gel bed without liposomes, confirming that the cations only interact with the immobilized liposomes. Effects of the solute concentration, flow rate, and gel-matrix substance on the ILC were studied. The stationary phase volume of the liposomal membranes was calculated from the volume of a phospholipid molecule and the amount of the immobilized phospholipid, which allowed us to determine the membrane partition coefficient (KLM) for the lipophilic cations distributed between the aqueous mobile and membrane stationary phases. The values of KLM were generally increased with the hydrophobicity of the solutes increased, and were higher for the SUVs than for the LUVs. The ILC method described here can be applied to measure membrane partition coefficients for other lipophilic solutes (e.g., drugs).  (+info)

Cation-π interaction is a non-covalent binding force that plays a significant role in protein stability and drug-receptor interactions. In this work, we have investigated the structural role of cation-π interactions in sugar-binding proteins (SBPs). We observed 212 cation-π interactions in 53 proteins out of 59 SBPs in dataset. There is an average one energetically significant cation-π interaction for every 66 residues in SBPs. In addition, Arg is highly preferred to form cation-π interactions, and the average energy of Arg-Trp is high among six pairs. Long-range interactions are predominant in the analyzed cation-π interactions. Comparatively, all interaction pairs favor to accommodate in strand conformations. The analysis of solvent accessible area indicates that most of the aromatic residues are found on buried or partially buried whereas cationic residues were found mostly on the exposed regions of protein. The cation-π interactions forming residues were found that around 43% of cation-π
Engineering of mixed-valence (MV) radical cations and intermolecular complexes based on pi-extended tetrathiafulvalenes (TTFs) is central for the development of organic conductors. On another front, redox-controlled dimerization of radical cations has recently been recognized as an important tool in supramolecular chemistry. Here we show that pi-extended TTFs based on the indenofluorene core, prepared by Horner-Wadsworth-Emmons reactions, undergo reversible and stepwise one-electron oxidations and that the detectable, intermediate radical cation forms remarkably strong intermolecular MV ([neutral.cation]) and pi-dimer ([cation.cation]) complexes with near-infrared radical cation absorptions. The radical cation itself seems to be a so-called Class III MV species in the Robin-Day classification. The formation of MV dimers was corroborated by ESR spectroelectrochemical studies, revealing two slightly different ESR signals upon oxidation, one assigned to the MV dimer and the other to the cation monomer.
In this work, we have analyzed the influence of cation-pi interactions to the stability of Sm/LSm assemblies and their environmental preferences. The number of interactions formed by arginine is higher than lysine in the cationic group, while histidine is comparatively higher than phenylalanine and tyrosine in the pi group. Arg-Tyr interactions are predominant among the various pairs analyzed. The furcation level of multiple cation-pi interactions is much higher than that of single cation-pi interactions in Sm/LSm interfaces. We have found hot spot residues forming cation-pi interactions, and hot spot composition is similar for all aromatic residues. The Arg-Phe pair has the strongest interaction energy of -8.81 kcal mol(-1) among all the possible pairs of amino acids. The extent of burial of the residue side-chain correlates with the Delta Delta G of binding for residues in the core and also for hot spot residues cation-pi bonded across the interface. Secondary structure of the cation...-pi ...
Over the last several years, various gene delivery systems have been developed for gene therapy applications. Although viral vector-based gene therapy has led
TY - JOUR. T1 - Denatured and reversibly cationized p53 readily enters cells and simultaneously folds to the functional protein in the cells. AU - Murata, Hitoshi. AU - Sakaguchi, Masakiyo. AU - Futami, Junichiro. AU - Kitazoe, Midori. AU - Maeda, Takashi. AU - Doura, Hideki. AU - Kosaka, Megumi. AU - Tada, Hiroko. AU - Seno, Masaharu. AU - Huh, Nam Ho. AU - Yamada, Hidenori. PY - 2006/5/16. Y1 - 2006/5/16. N2 - Cationization is a powerful strategy for internalizing a protein into living cells. On the other hand, a reversibly cationized denatured protein through disulfide bonds is not only soluble in water but also able to fold to the native conformation in vitro. When these advantages in cationization were combined, we developed a novel method to deliver a denatured protein into cells and simultaneously let it fold to express its function within cells. This in-cell folding method enhances the utility of recombinant proteins expressed in Escherichia coli as inclusion bodies; that is, the ...
The visible light combined with photosensitizers (PSs) is exploited in both antitumoral and antimicrobial fields inducing a photo-oxidative stress within the target cells. Among the different PSs, porphyrins belong to the family of the most promising compounds to be used in clinical photodynamic applications. Although in the last years many porphyrins have been synthesised and tested, only a few reports concern the in vitro effects of the 5,15-diarylporphyrins. In this work, the activity of four 5,15-diarylporphyrins (compounds 7-10), bearing alkoxy-linked pyridinium appendixes, have been tested on cancer cell lines and against bacterial cultures. Among the synthetized PSs, compounds 7 and 9 are not symmetrically substituted porphyrins showing one cationic charge tethered at the end of one 4C or 8C carbon chains, respectively. On the other hand, compounds 8 and 10 are symmetrically substituted and show two chains of C4 and C8 carbons featuring a cationic charge at the end of both chains. The ...
Müller, A., Krickemeyer, E., Bögge, H., Schmidtmann, M., Botar, B., & Talismanova, M. O. (2003). Drawing small cations into highly charged porous nanocontainers reveals Water assembly and related interaction problems. ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 42(18), 2085-2090. doi:10.1002/anie. ...
RESULTS: Viscometry first showed that these polymers display typical polysoap behaviour in hydro‐alcoholic mixtures. Fluorescence spectrometry was then used to characterize the corresponding intramolecular association with two complementary fluorescent probes. In addition to confirming macromolecular folding, pyrene provided information about the probe local environment polarity whereas a molecular rotor gave interesting complementary information about the compactness of the corresponding nano‐domains ...
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Synonyms for Cations, divalent in Free Thesaurus. Antonyms for Cations, divalent. 1 synonym for divalent: bivalent. What are synonyms for Cations, divalent?
View Notes - 0243Pb45anp2-09 from CHEM orgo at NYU. + + Both cations (these are NOT resonance forms - they are two separate cations) are captured - two steps please - to give the two final products.
Summary: This chapter focuses on changeover metals. All transition metal cations are toxic-the ones that are essential for Escherichia coli and belong to the main get redirected here transition period of the periodic program with the element and also the toxic-only metals with increased atomic figures. Prevalent themes are noticeable inside the metabolism of those ions. To start with, there is transport. Superior-price but minimal-affinity uptake techniques offer many different cations and anions on the cells. Charge of the respective systems is apparently mainly via regulation of transport action (flux Management), with Charge of gene expression enjoying just a slight role. If these units never deliver adequate amounts of a desired ion into the mobile, genes for ATP-hydrolyzing superior-affinity but very low-fee uptake techniques are induced, e.g., ABC transport methods or P-kind ATPases. However, if the level of an ion is in surplus, genes for efflux methods are induced. from this source By ...
The directed movement of inorganic cations with a valency of one into, out of, within or between cells. Inorganic cations are atoms or small molecules with a positive charge which do not contain carbon in covalent linkage ...
The directed movement of inorganic cations with a valency of one into, out of, within or between cells. Inorganic cations are atoms or small molecules with a positive charge which do not contain carbon in covalent linkage ...
What does the name Cation mean? Learn about the meaning, origin, popularity, and more! Explore the history of your surname at Findmypast.
1AEG: Artificial protein cavities as specific ligand-binding templates: characterization of an engineered heterocyclic cation-binding site that preserves the evolved specificity of the parent protein.
1AEE: Artificial protein cavities as specific ligand-binding templates: characterization of an engineered heterocyclic cation-binding site that preserves the evolved specificity of the parent protein.
Structural Diversity and Thermochromic Properties of Iodobismuthate Materials Containing d-Metal Coordination Cations: Observation of a High Symmetry [Bi3I11]2− Anion and of Isolated I− Anions
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Article: Teamwork allows people to discuss their work together, and as a result, to grow professionally. To be successful, the teacher and para-educator must view themselves as a team and partners in the educational process ...
1776. Somme des cations échangeables (S) : Somme des cations métalliques échangeables exprimée en milliéquivalents-grammes pour 100 grammes de complexe absorbant ...
TY - JOUR. T1 - Cationic lipid-mediated NGF gene transfection increases neurofilament phosphorylation. AU - Yang, K.. AU - Xue, J. J.. AU - Qiu, Y. H.. AU - Perez-Polo, J. R.. AU - Whitson, J.. AU - Faustinella, F.. AU - Kampfl, A.. AU - Zhao, X.. AU - Iwamoto, Y.. AU - Mu, X. S.. AU - Clifton, G.. AU - Hayes, R. L.. PY - 1996/12/31. Y1 - 1996/12/31. N2 - We examined the effect of cationic lipid-mediated gene transfection of nerve growth factor (NGF) in primary septo-hippocampal cell cultures. Rat NGF cDNA was subcloned into a pUC19-based plasmid containing a CMV promoter. Two days after NGF gene transfection in primary cell cultures, ELISA confirmed increases in NGF protein secretion from transfected cells. To study the biological effect of cationic lipid-mediated NGF gene transfection, we analyzed the amount of neurofilament protein from NGF-transfected cell cultures. Western blot and immunohistochemical analyses detected significant increases in the phosphorylated form of neurofilament ...
Non-viral vectors based on cationic niosomes as efficient gene delivery vehicles to central nervous system cells into the brain Academic Article 2018 ...
The dyes were first introduced by Hoechst, based on ß-sulphato ethyl sulphone as a reactive group. The range made the successful breakthrough due to comprehensive shade range, versatile application, ability to be dyed at 60°C and good compatibility with other bifunctional dyes. Being a compact structure, it offers ease in wash off for removal of unfixed dyes at the end of dyeing during washing. The dye fibre bond offers good acid stability. With the limitations to above, there may be problems with reproducibility associated with it, which is not accepted especially for pale shades. There is the possibility of unlevel dyeing with a small variation in the process due to its lower molecular weight. Hetero bifunctional dyes made a get through in early 80s. The dyes were based on a quite simple but beautiful chemistry. They had filled a big vacuum of various hues of bright shades, which were not possible with vinyl sulphone type. The dyes were conventional dichlorotriazine type, with the end ...
An industrially scalable and versatile method to prepare amphiphilic and amphoteric multifunctionalized polyurethane/polyurea nanocapsules (NCs) is presented. Firstly, a prepolymer is prepared from a diisocyanate, which reacts with different functional diols and diamines, leading to a self-emulsifiable react
The well-known Toll like receptor 9 (TLR9) agonist CpG ODN has shown promising results as vaccine adjuvant in preclinical and clinical studies, however its in vivo stability and potential systemic toxicity remain a concern. In an effort to overcome these issues, different strategies have been explored including conjugation of CpG ODN with proteins or encapsulation/adsorption of CpG ODN into/onto liposomes. Although these methods have resulted in enhanced immunopotency compared to co-administration of free CpG ODN and antigen, we believe that this effect could be further improved. Here, we designed a novel delivery system of CpG ODN based on its conjugation to serve as anchor for liposomes. Thiol-maleimide chemistry was utilised to covalently ligate model protein with the CpG ODN TLR9 agonist. Due to its negative charge, the protein conjugate readily electrostatically bound cationic liposomes composed of 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC), cholesterol and ...
The barrier for the radical isomerization CH3Oo --, oCH2OH is calculated by CBS-QB3 to be 29.7 kcal mol-1 and lies higher (by 5.7 kcal mol-1) than the dissociation limit CH2O+Ho. Hence, CH3Oo does not isomerize to the more stable oCH2OH on its own. However, this barrier is reduced to 15.8 ... read more kcal mol-1 when the CH3Oo radical is coordinated with protonated methanol (CH3-Oo...H-O(H)-CH3+) and the CH3Oo --,oCH2OH rearrangement can now take place within the complex. This rearrangement, which results in the hydrogen-bridged radical cation oCH2-O(H)...H-O(H)-CH3+ can be viewed as an acid catalyzed rearrangement. The ion CH3-Oo...H-O(H)-CH3+ represents the most stable form of the methanol dimer radical cation. The ion oCH2-O(H)...H-O(H)-CH3+ can fragment directly to CH3OH2+ + oCH2OH or it can rearrange further to produce the hydrogen-bridged radical cation oCH2-O+(CH3)-H...OH2, which is the dimethylether ylid cation solvated by water. This species can dissociate to its components or tho ...
TY - JOUR. T1 - Radical cations of benzo[α]pyrene and 6-substituted derivatives. T2 - Reaction with nucleophiles and DNA. AU - Stack, D. E.. AU - Cremonesi, P.. AU - Hanson, A.. AU - Rogan, E. G.. AU - Cavalieri, E. L.. PY - 1995. Y1 - 1995. N2 - 1. Oxidation of benzo[α]pyrene (BP) by I2 in the presence of AgClO4 in benzene generates the BP+ ClO4- · AgI complex. This same method was used to produce radical cations from 6-FBP, 6-ClBP, 6-BrBP and 6-CH3BP. 2. Reaction of the BP, 6-FBP, 6-ClBP and 6-BrBP radical cation perchlorates with H2O produced BP 1,6-, 3,6- and 6,12- dione, whereas 6-CH3BP.+ ClO4- · AgI yielded 6-CH2OHBP. 3. When BP.+ ClO4- · AgI and 6-FBP.+ ClO4- · AgI were reacted with NaOAc in H2O/CH3CN (9:1), 6-OAcBP was formed, in addition to the quinones. In the case of 6-ClBP.+ ClO4- · AgI, a small amount of 1-OAc-6-ClBP and 3-OAc-6-ClBP was formed in addition to the diones, whereas for 6-BrBP and 6-CH3BP the reaction products were BP diones and 6-CH2OHBP respectively. 4. These ...
Antimicrobial peptides (AMPs) are a class of antimicrobial agents with broad-spectrum activities. Several reports indicate that cationic AMPs bind to the negatively charged bacterial membrane causing membrane depolarization and damage. However, membrane depolarization and damage may be insufficient to elicit cell death, thereby suggesting that other mechanism(s) of action could be involved in this phenomenon. In this study, we investigated the antimicrobial activity of a novel antimicrobial peptide, TP359, against two strains of Pseudomonas aeruginosa, as well as its possible mechanisms of action. TP359 proved to be bactericidal against P. aeruginosa as confirmed by the reduced bacteria counts, membrane damage and cytoplasmic membrane depolarization. In addition, it was non-toxic to mouse J774 macrophages and human lung A549 epithelial cells. Electron microscopy analysis showed TP359 bactericidal effects by structural changes of the bacteria from viable rod-shaped cells to those with cell membrane
A promising strategy to improve the immunogenic potential of DNA vaccines is the formulation of plasmid DNA (pDNA) with cationic liposomes. In this respect, particle size may be of crucial importance. This study aimed at the evaluation of high-pressure extrusion as a method for sizing cationic liposomes after entrapment of pDNA. This is a well-known sizing method for liposomes, but so far, it has not been applied for liposomes that are already loaded with pDNA. Liposomes composed of egg PC, DOTAP, and DOPE with entrapped pDNA were prepared by the dehydration-rehydration method and subjected to various extrusion cycles, comparing different membrane pore sizes and extrusion frequencies. At optimized extrusion conditions, liposome diameter (Zave) and polydispersity index (PDI) were reduced from 560 nm and 0.56 to 150 nm and 0.14 respectively, and 35% of the pDNA was retained. Importantly, gel electrophoresis and transfection experiments with pDNA extracted from these extruded liposomes demonstrated ...
Qilei Zhu, Emily C. Gentry, Robert R. Knowles:. https://onlinelibrary.wiley.com/doi/full/10.1002/anie.201604619. ABSTRACT: A new catalytic method is described to access carbocation intermediates via the mesolytic cleavage of alkoxyamine radical cations. In this process, electron transfer between an excited state oxidant and a TEMPO‐derived alkoxyamine substrate gives rise to a radical cation with a remarkably weak C−O bond. Spontaneous scission results in the formation of the stable nitroxyl radical TEMPO. as well as a reactive carbocation intermediate that can be intercepted by a wide range of nucleophiles. Notably, this process occurs under neutral conditions and at comparatively mild potentials, enabling catalytic cation generation in the presence of both acid sensitive and easily oxidized nucleophilic partners.. ...
TY - JOUR. T1 - Cu(I) recognition via cation-π and methionine interactions in CusF. AU - Xue, Yi. AU - Davis, Anna V.. AU - Balakrishnan, Gurusamy. AU - Stasser, Jay P.. AU - Staehlin, Benjamin M.. AU - Focia, Pamela. AU - Spiro, Thomas G.. AU - Penner-Hahn, James E.. AU - OHalloran, Thomas V.. PY - 2008/2. Y1 - 2008/2. N2 - Methionine-rich motifs have an important role in copper trafficking factors, including the CusF protein. Here we show that CusF uses a new metal recognition site wherein Cu(I) is tetragonally displaced from a Met 2His ligand plane toward a conserved tryptophan. Spectroscopic studies demonstrate that both thioether ligation and strong cation-π interactions with tryptophan stabilize metal binding. This novel active site chemistry affords mechanisms for control of adventitious metal redox and substitution chemistry.. AB - Methionine-rich motifs have an important role in copper trafficking factors, including the CusF protein. Here we show that CusF uses a new metal ...
Semple, SC, Akinc, A, Sandhu, A, Mui, B, Chow, C, Sah, D, Stebbing, D, Crosley, E, Hafez, I, Dorkin, JR, Qin, J, Lam, K, Wong, K, Nechev, L, Eisenhardt, ML, Jayaraman, M, Kazem, M, Maier, M, Srinivasulu, M, Weinstein, M, Chen, Q, Alvarez, R, Barros, S, Klimuk, SK, Borland, T, Kosovrasti, V, Tam, Y, MacLachlan, I, Manoharan, M, Ciufolini, MA, Tracy, M, de Fougerolles, A, Cullis, PR, Madden, TD, Hope, ...
Experimental and Theoretical Examination of the Radical Cations Obtained from the Chemical and Electrochemical Oxidation of 5-AminothiazolesExperimental and Theoretical Examination of the Radical Cations Obtained from the Chemical and Electrochemical Oxidation of 5-Aminothiazoles ...
TY - JOUR. T1 - Indirect cation-flow method. T2 - Flash generation of alkoxycarbenium ions and studies on the stability of glycosyl cations. AU - Saito, Kodai. AU - Ueoka, Koji. AU - Matsumoto, Kouichi. AU - Suga, Seiji. AU - Nokami, Toshiki. AU - Yoshida, Jun Ichi. PY - 2011/5/23. Y1 - 2011/5/23. N2 - Go with the flow: The indirect cation-flow method based on the generation of highly reactive organic cations from their precursors using electrochemically generated [ArS(ArSSAr)]+ was developed in flow microreactor systems (see scheme; Bn=benzyl, M=micromixer, R=microtube reactor). The method was applied to evaluate glycosyl cations such as A or their equivalents and glycosylation reactions.. AB - Go with the flow: The indirect cation-flow method based on the generation of highly reactive organic cations from their precursors using electrochemically generated [ArS(ArSSAr)]+ was developed in flow microreactor systems (see scheme; Bn=benzyl, M=micromixer, R=microtube reactor). The method was applied ...
Non-stop carbocationic polycyclizations of isoprenoids have been called the most complex chemical reactions occurring in nature. We describe a strategy for the initiation of tail-to-head polycyclization that relies on the sequestration of the counteranion away from the carbocation, which allows full propagation of the cationic charge. If the anion is mobile, Coulombic forces hold this species in close proximity to the carbocation and cause preemptive termination through elimination. Anion sequestration is crucial for effecting the biomimetic synthesis of complex and unstable terpenes, including the highly strained funebrenes. This study illustrates the deleterious role of the counterion in tail-to-head carbocationic polycyclization reactions, which to the best of our knowledge has not been rigorously explored. These observations are also expected to find use in the design and control of cationic polycyclization along biosynthetic pathways that have previously been inaccessible in bulk solvent ...
TY - JOUR. T1 - The dithiacyclooctane cation (DTCO+). T2 - Conformational analysis, interconversion barriers and bonding. AU - Stowasser, Ralf. AU - Glass, Richard S. AU - Hoffmann, Roald. PY - 1999/7. Y1 - 1999/7. N2 - A theoretical conformation analysis of the dithiacyclooctane radical cation (DTCO+) suggests that the lowest energy conformer is a chair-boat, with a partial but significant S-S σ bond. For the ring flip process of this molecule we calculate a barrier of 40 kJ mol-1 and two possible pathways: one involves a boat-boat conformer and an untwisted transition structure, the other a chair-chair conformer and a twisted transition structure.. AB - A theoretical conformation analysis of the dithiacyclooctane radical cation (DTCO+) suggests that the lowest energy conformer is a chair-boat, with a partial but significant S-S σ bond. For the ring flip process of this molecule we calculate a barrier of 40 kJ mol-1 and two possible pathways: one involves a boat-boat conformer and an ...
Histochemical and morphological research increasingly relies upon quanti cation of complex biological systems. For such investigations to be meaningful, quanti cation techniques must meet the seemingly conflicting requirements of being theoretically robust, yet sufficiently practical to facilitate widespread applicability. Validity ought to be enhanced by theoretical simplicity, use of measured rather than assumed variables, and minimising observer interpretation. Practicality is facilitated by simplifying and reducing measurements, broadening applicability, and reducing costs and analysis time. As a result, quanti cation systems that rely upon sampling and estimation have been favoured over serial reconstruction techniques. To provide reliable estimates, sampling must be valid at all levels from tissue harvest, to the selection of microscope fields in which quanti cation is performed by techniques that account for the anisotropic distribution, and variable size of many elements in biological ...
Positively charged cations and negatively charged anions attract one another. Conversely, cations repel one another as do anions.. Electrostatic attraction is indiscriminate. That is a cation can attract more than one anion and visa versa. The result is that cation-anions attractions form a large array that we call an ionic compound or salt. The bonds holding these ions together are called ionic bonds. However, this array has a very specific composition completely dictated by the charges on the cations and anions.. Formulas of ionic compounds:. The composition of ionic compounds is determined by the requirement that the compounds must be electrically neutral. That is that the charges of the cations and anions must balance or cancel out one another. For example consider sodium cations (Na+) and Chlorine anions (Cl ). Sodium has a positive 1 charge and chloride has a negative 1 charge. Thus one sodium cation cancels one chloride anion (+1 + 1 = 0) resulting in the formula Na1Cl1 or NaCl. ...
We value your input so if you have suggestions regarding new applications for CARBOMETHOXYMETHYL TRIPHENYLPHOSPHONIUM CHLORIDE email us and we will include your contribution on the website.. Enquire about product ...
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We present a detailed analysis of the anomalous carbocations: C2H5+ and C3H3+. This work involves (a) probing electronic structural properties, (b) ab initio dynamics simulations over a range of internal energies, (c) analysis of reduced dimensional potential surfaces directed along selected conformational t
View Notes - Lecture21outline from CHEM 0740 at Pittsburgh. I. Review Nucleophiles generally add to anomeric carbocations from the axial face This is a result of the anomeric effect that states that
Compartment GO Term. serotonin-activated cation-selective channel complex onclick=removeFacet(Compartment GO Term/serotonin-activated cation-selective channel complex)> Compartment GO Term serotonin-activated cation-selective channel complex ...
Page contains details about cationic liposomes 9:1 . It has composition images, properties, Characterization methods, synthesis, applications and reference articles : nano.nature.com
eng] Geometries and binding energies of complexes of cations with benzene, [2.2]paracyclophane and a [2.2]paraheterocyclophane are computed and compared using ab initio calculations. [2.2]Paracyclophane is not used for building cation receptors because of its small cavity. Here, we demonstrate that its binding capability toward cations using one aromatic ring is superior to benzene in 10 kcal/mol. This unexpected difference is explained by the reduction, upon complexation, of the repulsive interaction of the psystems, which is due to the close proximity of the two benzene rings. Experimental results derived from the analysis of X-ray structures retrieved from the CSD support this explanation ...
Cyclic nucleotideCgated (CNG) ion stations are non-selective cation stations with a higher permeability for Ca2+. a keeping potential of 0 mV to between ?60 and +80 mV in increments of 20 mV for 15 s to attain steady-state of stop. Stop versus voltage data had been match the Boltzmann formula, unless usually indicated: (2) where z may be the valence from the blocker (two for dequalinium), may be the electric distance from the blocker within the pore, T may be the overall temperatures, and k is certainly Boltzmanns continuous. Data 129938-20-1 manufacture are plotted, unless indicated usually, 129938-20-1 manufacture because the fractional current attained by dividing the obstructed current by the utmost unblocked current and reported because the mean SEM. Period courses of stop could be match an individual exponential. Modeling Predictions from the voltage dependence from System I were computed numerically utilizing the analytical appearance for the open up probability being a function of ...
C1-CBP-vancomycin: Impact of a vancomycin C-terminus trimethylammonium cation on pharmacological properties and insights into its newly introduced mechanism of action ...
Used for cation analysis by Ion Chromatography, these standards for cation analysis can be used for primary calibration or to prepare second source calibration check standards.
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Acronym using Cation. Acronym including the word Cation Acronyms with CATIONFurther acronym search. Find the acronyms that include a word!
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Buryi, VA ; Morel, Nicole ; Godfraind, Theophile. Model of cation channel gating.In: Progress in Biophysics & Molecular Biology, Vol. 65, p. PC330-PC330 (1996 ...
During the study of the radical induced DNA strand cleavage, we observed the appearance of a radical cation at the carbohydrate backbone.1 This radical cation is a strong oxidant that can be reduced by an adjacent guanosine (G).2 The so formed guanine
An atom with more protons than electrons, giving it a net positive charge. For example, a sodium atom becomes a cation when it transfers an electron to a chlorine atom to form sodium chloride. See also Ion and Anion.. ...
has moved to a new address:. SPM Chemistry Form 4/Form 5 Revision Notes: Identifying Cations - Test with Chloride Ions Sorry for the inconvenience… Redirection provided by Blogger to WordPress Migration Service ...
Waters offers an array of products for ion chromatography . IC-Pak resin based columns allow you to analyze a full range of ions from numerous sample matrices, both simple and complex. They offer an exceptional linear loading range of less than 1.0 ppb to greater than 400 ppm without dilution and without pH limitation on eluent or sample. The flexibility exists for accurate and reproducible anion and cation analyses at all concentration levels.
Wolf, R., Dommröse, A. - M., & Grützmacher, H. - F. (1988). Destabilized carbenium ions: secondary and tertiary [alpha]-carbomethoxybenzyl cations. Organic Mass Spectrometry, 23(1), 26-32. doi:10.1002/oms. ...
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Maximum efficiency of cation hydrolysis will be shown by? a) \(\sf Al^{+3}\) b) \(\sf Tl^{+3}\) c) \(\sf Tl^{+1}\) d) \(\sf Ga^{+3}\)The answer i...
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Cations are positively charged ions and anions are negatively charged ions. Metals act as cations and willingly give up or donate electrons to nonmetals. Nonmetals act as anions and accept donated...
C60 cations[edit]. C60 oxidizes with difficulty. Three reversible oxidation processes have been observed by using cyclic ... Redox reactions - C60 anions and cations[edit]. C60 anions[edit]. See also: Fullerides ... 7.7 Redox reactions - C60 anions and cations *7.7.1 C60 anions ...
Identification of alkaline earth cations[edit]. The flame test The table below[74] presents the colours observed when the flame ... which the alkaline earth metals readily lose to form cations with charge +2, and an oxidation state of +2.[5] ...
Cation exchange[edit]. Cation exchange sorbents are derivatized with functional groups that interact and retain positively ... Strong cation exchange sorbents contain aliphatic sulfonic acid groups that are always negatively charged in aqueous solution, ... Strong cation exchange sorbents are useful because any strongly basic impurities in the sample will bind to the sorbent and ... and weak cation exchange sorbents contain aliphatic carboxylic acids, which are charged when the pH is above about 5. ...
Guanidinium cation[edit]. The conjugate acid is called the guanidinium cation, (C(NH. 2)+. 3). This planar, symmetric ion ... Via the intermediacy of biguanidine, this ammonolysis step affords salts of the guanidinium cation (see below). In the second ... 1 cation in aqueous solution due to the efficient resonance stabilization of the charge and efficient solvation by water ...
Anion/cation analysis[edit]. See also: Qualitative inorganic analysis. Precipitate formation is useful in the detection of the ... To identify the cation, the color of the precipitate and its solubility in excess are noted. Similar processes are often used ... type of cation in a salt. To do this, an alkali first reacts with the unknown salt to produce a precipitate that is the ...
Flavylium cation derivatives[edit]. Main article: Anthocyanidin. Selected anthocyanidins and their substitutions Basic ... October 2008). "Singlet oxygen quenching by anthocyanin's flavylium cations". Free Radical Research. 42 (10): 885-91. doi: ...
The phosphonium (more obscurely: phosphinium) cation describes polyatomic cations with the chemical formula PR+. 4 (R = H, ... Types of phosphonium cationsEdit. Protonated phosphinesEdit. The parent phosphonium is PH+. 4 as found in the iodide salt, ... The quaternary phosphonium cations include tetraphenylphosphonium, (C6H5)4P+ and tetramethylphosphonium P(CH. 3)+. 4. ... Quaternary phosphonium cations (PR+. 4) are produced by alkylation of organophosphines.[3] For example, the reaction of ...
... cationsEdit. The adamantane cation can be produced by reacting 1-fluoro-adamantane with SbF5 and it has high ... tert-butanol (t-BuOH) and sulfuric acid were added to generate adamantane cation; the cation was then carboxylated by carbon ... The 1-Adamantyl Cation". J. Am. Chem. Soc. 86 (19): 4195-4197. doi:10.1021/ja01073a058.. ... and related cations and dications". J. Am. Chem. Soc. 107 (9): 2764-2772. doi:10.1021/ja00295a032.. ...
Carbazole cations". Polymer. 24 (6): 733-738. doi:10.1016/0032-3861(83)90012-5. Partridge, R (1983). "Electroluminescence from ...
... silylium cations; [E(bipy)2]3+ (E = P, As, Sb, Bi) cations; cationic 4 coordinate Pv and Sbv derivatives) and transition-metal ... and borenium cations, and its application to these and various other boron compounds has been reviewed. The Gutmann-Beckett ... 3 and synthons for EI and Ev cations", Chemical Sciences, 2015, 6, 6545-6555. doi: 10.1039/C5SC02423D J.M. Bayne and D.W. ...
"Complex Fluoro Cations. II. Tetrafluoronitrogen(V) Cation, NF4+. Synthesis and Properties of NH4+AsF6−". Inorganic Chemistry. 5 ... The hexafluorochlorine (VII) cation, CIF6+, K. O. Christe, Inorg. Nucl. Chem. Lett. 8, 751, (1972) Christe, Karl O. (1973). " ... In this context, he synthesized the bent pentazenium cation, N5+, and was the first to experimentally detect the cyclic ... cation, CIF6". Inorganic and Nuclear Chemistry Letters. 8 (8): 741-745. doi:10.1016/0020-1650(72)80129-6. Chem.usc.edu ...
TCN-213; Cations: Hydrogen. *Magnesium. *Zinc; Alcohols/volatile anesthetics/related: Benzene. *Butane ...
TCN-213; Cations: Hydrogen. *Magnesium. *Zinc; Alcohols/volatile anesthetics/related: Benzene. *Butane ...
The NMDA receptor is a non-specific cation channel that can allow the passage of Ca2+ and Na+ into the cell and K+ out of the ... However, the NMDA receptor cation channel is blocked by Mg2+ at resting membrane potential.[109] Magnesium unblock is not ... Activation of NMDA receptors results in the opening of the ion channel that is nonselective to cations, with a combined ... cations) to flow through the cell membrane.[2] The NMDA receptor is thought to be very important for controlling synaptic ...
TCN-213; Cations: Hydrogen. *Magnesium. *Zinc; Alcohols/volatile anesthetics/related: Benzene. *Butane ...
NMDARs can open only when a depolarization from the AMPAR activation leads to repulsion of the Mg2+ cation out into the ... AMPA receptors (AMPAR) are both glutamate receptors and cation channels that are integral to plasticity and synaptic ... The AMPAR's permeability to calcium and other cations, such as sodium and potassium, is governed by the GluA2 subunit. If an ...
cations: 65% Li-7, 29.1% Be, 5% Zr, 0.9% U. weight: 11,260 lbs (5,107 kg). melting temp: 813 F (434 C). inlet temp: 1175 F (635 ... cations: 66% Li-7, 34% Be. weight: 15,300 lbs (6,940 kg). coolant pump circulating: 23,566 h ...
TCN-213; Cations: Hydrogen. *Magnesium. *Zinc; Alcohols/volatile anesthetics/related: Benzene. *Butane ...
TCN-213; Cations: Hydrogen. *Magnesium. *Zinc; Alcohols/volatile anesthetics/related: Benzene. *Butane ...
TCN-213; Cations: Hydrogen. *Magnesium. *Zinc; Alcohols/volatile anesthetics/related: Benzene. *Butane ...
In sufficiently acidic environments, the amino group gains a proton and the molecule becomes a cation with a single positive ...
TCN-213; Cations: Hydrogen. *Magnesium. *Zinc; Alcohols/volatile anesthetics/related: Benzene. *Butane ...
TCN-213; Cations: Hydrogen. *Magnesium. *Zinc; Alcohols/volatile anesthetics/related: Benzene. *Butane ...
In aqueous solution, Al3+ exists as the hexaaqua cation [Al(H2O)6]3+, which has an approximate pKa of 10−5. Such solutions are ... ISBN 978-3-527-30673-2. *Baes, C.F.; Mesmer, R.E. (1986) [1976]. The Hydrolysis of Cations. Malabar, FL: Robert E. Krieger. ... Furthermore, as Al3+ is a small and highly charged cation, it is strongly polarizing and aluminium compounds tend towards ... and is characteristic of weakly basic cations that form insoluble hydroxides and whose hydrated species can also donate their ...
Unlike its heavier congeners, it is not known to form a simple B3+ or hydrated [B(H2O)4]3+ cation. The small size of the boron ... It is not known to form a cation. Silicon can form alloys with metals such as iron and copper. It shows fewer tendencies to ... Whether or not germanium forms a cation is unclear, aside from the reported existence of the Ge2+ ion in a few esoteric ... Sources mentioning germanium cations include: Powell & Brewer who state that the cadmium iodide CdI2 structure of germanous ...
ISBN 0-13-879932-6. Kolle, U.; Grub, J. (1985). "Permethylmetallocene: 5. Reactions of Decamethylruthenium Cations". J. ...
The aluminium cation Al3+ is small and highly charged; as such, it is polarizing, and bonds aluminium forms tend towards ... In aqueous solution, Al3+ exists as the hexaaqua cation [Al(H2O)6]3+, which has an approximate pKa of 10−5. Such solutions are ... Although it is generally harmless to plant growth in pH-neutral soils, in acid soils the concentration of toxic Al3+ cations ... Furthermore, as Al3+ is a small and highly charged cation, it is strongly polarizing and bonding in aluminium compounds tends ...
Divalent cations (e.g. Mg2+) are also required for integrin-ligand binding. Integrin ligands ICAM-1 and VCAM-1 are activated by ...
The first hydrolysis step is given generically as M(H2O)nm+ + H2O ⇌ M(H2O)n−1(OH)(m−1)+ + H3O+ Thus the aqua cations behave as ... The salt also dissociates into its constituent anions and cations. For example, sodium acetate dissociates in water into sodium ... ISBN 0-471-97058-1. Baes, Charles F.; Mesmer, Robert E. (1976). The Hydrolysis of Cations. New York: Wiley. ISBN 9780471039853 ... Water spontaneously ionizes into hydroxide anions and hydronium cations. ...
... stabilize unusual cations. The first cationic derivative of alane, [H2Al(PMDTA)]+[AlH4]− was prepared by treating ...
A-Putative-Cation-Channel-NCA-1-and-a-Novel-Protein-UNC-80-Transmit-Neuronal-Activity-in-C.-elegans-pbio.0060055.sv002.ogv 20 s ... A-Putative-Cation-Channel-NCA-1-and-a-Novel-Protein-UNC-80-Transmit-Neuronal-Activity-in-C.-elegans-pbio.0060055.sv003.ogv 11 s ... A-Putative-Cation-Channel-NCA-1-and-a-Novel-Protein-UNC-80-Transmit-Neuronal-Activity-in-C.-elegans-pbio.0060055.sv004.ogv 33 s ... A-Putative-Cation-Channel-NCA-1-and-a-Novel-Protein-UNC-80-Transmit-Neuronal-Activity-in-C.-elegans-pbio.0060055.sv005.ogv 2 ...
The dihydrogen cation or hydrogen molecular ion is a cation (positive ion) with formula H+. 2. It consists of two hydrogen ... An electron is knocked off leaving the cation behind.[16] H2 + cosmic ray → H+. 2 + e− + cosmic ray.. Cosmic ray particles have ... 2 (ditritium cation). [4]. Quantum mechanical analysis[edit]. The Schrödinger equation (in the clamped-nuclei approximation) ... The dihydrogen cation has six isotopologues, that result from replacement of one or more protons by nuclei of the other ...
cation. Further reading[edit]. *"cation" in Trésor de la langue française informatisé (The Digitized Treasury of the French ... cation (plural cations) *(physical chemistry) a positively charged ion, i.e. one that would be attracted to the cathode in ... "cation", in Lexico. , Dictionary.com; Oxford University Press, 2019-present.. *"cation", in Merriam-Webster Online Dictionary. ... Retrieved from "https://en.wiktionary.org/w/index.php?title=cation&oldid=62387755" ...
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cation exchange Process in which cations in solution are exchanged with cations held on the exchange sites of mineral and ... cation exchange Process in which cations in solution are exchanged with cations held on the exchange sites of mineral and ... cation exchange A Dictionary of Earth Sciences © A Dictionary of Earth Sciences 1999, originally published by Oxford University ... www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/cation-exchange ...
... has role antioxidant (CHEBI:22586) cyanidin cation (CHEBI:27843) has role metabolite (CHEBI:25212 ... cyanidin cation (CHEBI:27843) is a 5-hydroxyanthocyanidin (CHEBI:140277) cyanidin cation (CHEBI:27843) is conjugate acid of ... cyanidin cation (CHEBI:27843). cyanidin 3-O-rutinoside (CHEBI:28064) has functional parent cyanidin cation (CHEBI:27843). ... cyanidin cation (CHEBI:27843). cyanin (CHEBI:3978) has functional parent cyanidin cation (CHEBI:27843). cyanin betaine (CHEBI: ...
... is a elemental copper (CHEBI:37404) copper cation (CHEBI:23378) is a transition element cation ( ... copper(1+) (CHEBI:49552) is a copper cation (CHEBI:23378). copper(2+) (CHEBI:29036) is a copper cation (CHEBI:23378). copper(3+ ... CHEBI:23378 - copper cation. Main. ChEBI Ontology. Automatic Xrefs. Reactions. Pathways. Models. ...
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Triethylsilyl Cations. By J. B. Lambert, George A. Olah, Golam Rasul, Xing-ya Li, Herwig A. Buchholz, Graham Sandford, G. K. ... Triethylsilyl Cations. By J. B. Lambert, George A. Olah, Golam Rasul, Xing-ya Li, Herwig A. Buchholz, Graham Sandford, G. K. ... Triethylsilyl Cations. By J. B. Lambert, George A. Olah, Golam Rasul, Xing-ya Li, Herwig A. Buchholz, Graham Sandford, G. K. ...
Allan Cations (10 October 1932 - 21 May 2015) was an Australian rules footballer who played for the Richmond Football Club in ... ISBN 978-1-921496-32-5. Allan Cationss playing statistics from AFL Tables. ...
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Introduction Cation is a drawless connection game for two players: Black and White. Its played on the intersections (points) ...
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While they are reactive intermediates, hydrogen bridged cations can be stabilized sterically. Hydrogen bridged cations are ... "Water-Catalyzed Interconversion of Conventional and Distonic Radical Cations: Methanol and Methyleneoxonium Radical Cation". ... Hydrogen-bridged cations are a type of charged species in which a hydrogen atom is simultaneously bonded to two atoms through ... In 1973, G. Olah was able to directly observe the 2-norbornyl cation by low-temperature NMR and confirm the presence of a non- ...
Resorts, hotels offer school-cations amid coronavirus pandemic. A Four Seasons in Mexico is providing study buddies and ... "school-cations," allowing students to remotely attend school while on vacation with family. ... history and sports classes as a part of their school-cation program. ...
Some effects of divalent cations on binding and engulfment of several metal oxides and carbon particles are... ... Anionic Group Divalent Cation Peritoneal Macrophage Carbon Particle Fe203 Particle These keywords were added by machine and not ... Metzger G.V., Casarett L.J. (1967) Some Effects of Divalent Cations on In Vitro Phagocytosis. In: Luzio N.R.D., Paoletti R. ( ... Some effects of divalent cations on binding and engulfment of several metal oxides and carbon particles are described. ...
The preparation of betaine cations of methine dyes by three methods, viz., cyanine condensations of some quaternary salts and ...
Plan a Bae-cation Now. It doesnt have to be Valentines Day to plan a bae-cation. In fact, you should plan more than one get ... Bae-cations Can Improve your Global Intelligence, Together. Bae-cations can also improve ones full understanding of diversity ... Taking a bae-cation gives you the time to strengthen your relationship and also improve your work life. Youll return to work ... Bae-cations might sound like a silly Millennial term thats better used to describe an MTV reality show, but these getaways can ...
Thus, in interactions of a cation with Tyr, we are considering only the cation-π interaction. In the actual protein, the cation ... Because a cation-π interaction contains both a cation and an aromatic, it is not clear whether the interacting pairs should ... To summarize, then, our protocol for selecting cation-π interactions is as follows. All cation-π pairs (K or R with F, Y, or W ... With 2,994 cation-π interactions in 230,504 residues, there is an average of 1 energetically significant cation-π interaction ...
Agilent Technologies Inc. today announced the availability of new ion exchange and size exclusion columns specifically designed for the analysis of bio-molecules including monoclonal antibodies, recombinant proteins, peptides, vaccine products and DNA/RNA. The columns provide robust, reproducible and high-resolution solutions for biopharmaceutical manufacturers to effectively monitor the safety, efficacy and stability of their products.. ...
Uptake of potassium by bacteria is regulated by a single protein that senses the concentration of this cation both inside the ... Transient receptor potential vanilloid 2 (TRPV2), a Ca2+-permeable cation channel, plays vital roles in the regulation of ...
Summer stay-cations are a great way to have fun without the hassle and expense of leaving town. Find 10 great summer stay- ... How can I plan a fun stay-cation?. How can you plan a fun stay-cation? Learn how to give yourself a much-needed break ... On your stay-cation, its time to break out of your rut and experience a culinary adventure right in your own neighborhood. ... So, this year, why not enjoy time off on your own terms with a stay-cation? Youll skip the hassle and the expense of flying or ...
Can you name the Common Monatoma Cations and Anions? Test your knowledge on this science quiz to see how you do and compare ... Science Quiz / Common Monatomic Cations Random Science Quiz Can you name the Common Monatoma Cations and Anions?. by ...
In this work we investigate the effect of ionic strength and seawater cations on slime formation dynamics and functionality. In ... Our study demonstrates that hagfish slime deployment is a well-timed, ionic-strength, and divalent-cation dependent dynamic ... Cation concentrations of 300-400 ppm result in a exudate/cation mass ratios of about 1/1.5-2 per cation as is the case for Ca2+ ... a) Water retention in ASW without divalent cations (Ca2+ and Mg2+) and ASW without monovalent cations (Na+ and K+). (b) Water ...
A cation exchange membrane is disclosed comprising fluorinated polymer layers which include, in order, a layer with sulfonic ... Cation exchange membrane and use. US4996098 *. Feb 28, 1989. Feb 26, 1991. E. I. Du Pont De Nemours And Company. Coated cation ... Electrolytic cation exchange membrane. US4490484 *. Oct 21, 1981. Dec 25, 1984. E. I. Du Pont De Nemours And Company. Membrane ... Cation exchange film and electrolytic tank with the same. WO2013137819A1 *. Mar 16, 2012. Sep 19, 2013. Technodye Dyingcolors ...
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A day off from school doesnt have to mean a day off from learning, exploring, and making friends! These one-day camps engage campers in a full day of crafts, hands-on and inquiry-driven activities, encounters with wild animal ambassadors, and a tour of the Zoo where each camper will get a chance to feed the goats in the Alex and Ani Farmyard. Each day camp runs 8:30 am - 3:30 pm with three age groups: • Ages 4 & 5: Tadpole Academy (max 10/day, full day only) • Ages 6 - 10: Adventures (max 30/day, divided into smaller groups based on ages) Theme: Guess Zoo! A whos who of your Zoo! Come explore the animals of Roger Williams Park Zoo and learn what you and your favorite snack have in common with our animals and their favorite foods. Inquiry based activities, crafts and games along with animal encounters will surely provide a day off from school to satisfy any appetite.
Some amphiphilic cations block the mitochondrial apoptosis-induced channel, MAC.. Martinez-Caballero S1, Dejean LM, Kinnally KW ...
Farm Stays or Hay-cations are the perfect summer getaway for suburbanites around the country looking for a way to teach their ... Families Seek for Educational Vacation Alternatives on Popular Hay-Cations. Farm Stays or Hay-cations are the perfect ... Families Seek for Educational Vacation Alternatives on Popular Hay-Cations. Farm Stays or Hay-cations are the perfect ... "Farm Stays" or "Hay-cations" have have been a go-to choice to find a vacation off the beaten path as well as a fun way to teach ...
WebMD provides information about interactions between Antacid Liquid-Simethicone II Oral and divalent-trivalent-cations- ... Tetracyclines/Divalent & Trivalent Cations Interactions. This information is generalized and not intended as specific medical ... Avidity of the tetracyclines for the cations of metal. Nature 1956 Mar 3;177(4505):433-4. ...
  • Laboratory experiments and field tests were conducted to determine the effect of inorganic cations on effluent from activated-sludge systems. (ingentaconnect.com)
  • Culinary stay-cations also serve as the perfect opportunity to get your family back on a healthy eating track, if you've fallen onto the fast food wagon. (howstuffworks.com)
  • I fell in love with the idea of stay-cations after taking my first one. (lifehack.org)
  • Laboratory experiments showed that monovalent cations tend to increase the concentration of solution biological polymers(biopolymers), whereas divalent cations tend to retain the biopolymers in the floc. (ingentaconnect.com)
  • The attachment or release of these microbially derived organic biopolymers and recalcitrant influent substrate may depend on the monovalent-to-divalent cation ratio and the concentration of iron. (ingentaconnect.com)
  • These antiporters mediate the exchange of monovalent cations, mainly Na + and K + , with one or two protons across the membrane. (nature.com)
  • Both the cations and the anions are monovalent. (answers.com)
  • f ) Permability ratios for different monovalent cations, as derived from changes of reversal potentials ( 31 ) of photocurrents when replacing Na + by the cation X + . Solutions used were: 115 mM XCl, 2 mM BaCl 2 , 1 MgCl 2 , pH 9. (pnas.org)
  • A novel fluorinated cation exchange membrane containing carboxylic acid groups and sulfonic acid groups, both in the form of a specific pendant structure, the carboxylic acid groups being at least 20% on one surface of the membrane and gradually decreasing toward the innerside of the membrane, which. (google.com)
  • This invention relates to a novel fluorinated cation exchange membrane having both carboxylic acid groups and sulfonic acid groups, intermediates and starting materials for production thereof and also to processes for producing such materials. (google.com)
  • This invention also concerns a novel fluorinated cation exchange membrane having sulfonic acid groups with a high ion-exchange capacity and being provided with physically high strength. (google.com)
  • A cation exchange membrane is disclosed comprising fluorinated polymer layers which include, in order, a layer with sulfonic exchange groups, a layer with carboxylic exchange groups, and a thinner layer with carboxylic exchange groups at a greater exchange capacity than the other carboxylic layer. (google.com)
  • The cation exchange membrane according to the present invention can be used in electrolysis of an aqueous alkali metal halide solution under more severe conditions than those conventionally used while maintaining excellent performance stably for a long time. (google.com)
  • The greatest factor which controls the economy of the ion-exchange membrane process is the characteristic of the cation exchange membrane employed. (google.com)
  • It is necessary for the cation exchange membrane to satisfy the requirements as set forth below. (google.com)
  • Enables the transfer of cation from one side of a membrane to the other. (yeastgenome.org)
  • Cation Exchange Membranes are proton-conductive polymer film, also known as electrolyte or ionomer, that allow only protons to cross-over (cation exchange), the key function of proton exchange membrane fuel cells and water electrolyzers. (fuelcellstore.com)
  • Basically, cation exchange membranes perform as a separator and solid electrolyte in a variety of electrochemical cells that require the membrane to selectively transport cations across the cell junction. (fuelcellstore.com)
  • Chemours (formerly DuPont) Nafion™ 1110 membranes are non-reinforced cation exchange membrane fil. (fuelcellstore.com)
  • Chemours' (formerly DuPont) Nafion™ N-324 is a perfluorosulfonic acid cation exchange membrane co. (fuelcellstore.com)
  • Fumasep F-10270-PTFE-e membrane is an extruded per-flourinated sulfonic acid cation exchange memb. (fuelcellstore.com)
  • Fumapem FS-715-RFS membrane is perfluorinated cation exchange membrane - reinforced and stabilize. (fuelcellstore.com)
  • Fumapem FS-930 membrane is a perfluorinated cation exchange membrane - non-reinforced and stabili. (fuelcellstore.com)
  • Fumasep FS-720 membrane is perfluorinated cation exchange membrane - non-reinforced with low resi. (fuelcellstore.com)
  • Our Cation Membrane Variety Kits consist of one 10cm x 10cm piece of each of the following membra. (fuelcellstore.com)
  • Functionally, CPAs are often classified based on two phenotypes, their ion selectivity, i.e., whether they transport Na + or K + , and their electrogenicity, i.e., whether a cation exchanges for one (electroneutral) or two (electrogenic) protons. (nature.com)
  • Since cations tend to lose electrons, their atomic radius will decrease in size, as the other electrons will be 'pulled in' more by the protons in the nucleus (meaning stronger bond). (answers.com)
  • Your island vibes are sure to shine in the Tommy Bahama® Beach-Cation camp shirt. (zappos.com)
  • Rated 5 out of 5 by tom hughes from beach-cation camp shirt I love the shirt. (tommybahama.com)
  • Our study demonstrates that hagfish slime deployment is a well-timed, ionic-strength, and divalent-cation dependent dynamic hydrogel formation process. (nature.com)
  • Cation-π interactions in protein structures are identified and evaluated by using an energy-based criterion for selecting significant sidechain pairs. (pnas.org)
  • Cation-π interactions are found to be common among structures in the Protein Data Bank, and it is clearly demonstrated that, when a cationic sidechain (Lys or Arg) is near an aromatic sidechain (Phe, Tyr, or Trp), the geometry is biased toward one that would experience a favorable cation-π interaction. (pnas.org)
  • Theoretical and experimental studies have shown that cation-π interactions can be quite strong, both in the gas phase and in aqueous media. (pnas.org)
  • A number of studies have established a role for cation-π interactions in biological recognition, especially in the binding of acetylcholine ( 4 , 5 ). (pnas.org)
  • Here we present a detailed analysis of the extent and nature of cation-π interactions that are intrinsic to a protein's structure and likely contribute to protein stability. (pnas.org)
  • We find that energetically significant cation-π interactions are common in proteins-a "typical" protein will contain several. (pnas.org)
  • Important early work indicated a role for cation-π interactions in protein structures. (pnas.org)
  • In addition, explicit studies of Arg interacting with aromatic residues have been reported by Flocco and Mowbray ( 18 ) and by Thornton ( 14 ), and other efforts to search the Protein Data Bank (PDB) for cation-π interactions between ligands and proteins have been reported ( 19 , 20 ). (pnas.org)
  • In addition, not all cation-aromatic contacts represent energetically favorable cation-π interactions. (pnas.org)
  • To circumvent this problem, and to put the diverse array of potential cation-π interactions on a more nearly equal footing, we have chosen to use energy-based, rather than geometry-based, criteria in this study. (pnas.org)
  • First, we wish to develop meaningful statistics for cation-π interactions for structures within the PDB ( 21 ). (pnas.org)
  • Second, we wish to develop a simple, unambiguous protocol for identifying cation-π interactions that can be easily applied by other workers. (pnas.org)
  • Within a protein, cation-π interactions can occur between the cationic sidechains of either lysine (Lys, K) or arginine (Arg, R) and the aromatic sidechains of phenylalanine (Phe, F), tyrosine (Tyr, Y) or tryptophan (Trp, W). Because histidine can participate in cation-π interactions as either a cation or as a π-system, depending on its protonation state, we do not consider histidine in this study. (pnas.org)
  • These results improve our understanding of the essential role of cations in the biological function of bpDNase I. The high degree of conservation of the amino acids involved in the identified cation-binding sites across DNase I and DNase I-like proteins from various species suggests that our findings generally apply to all DNase I-DNA interactions. (nih.gov)
  • The substituents were systematically varied to investigate cation-π interactions in the S4 pocket, optimal heterocyclic stacking on the flat peptide walls lining the S1 pocket, and potential water replacements in both the S1 and the S4 pockets. (rcsb.org)
  • Since this is not an analysis of the stereochemistry of the metal first coordination spheres, any type of contact between a metal ion and other atoms was considered, independently of the type of metal cation, its oxidation state, its spin state, its coordination number, and independently of the type of atom(s) surrounding the metal and of the type of interatomic interactions (covalent, ionic). (mdpi.com)
  • Tannins, proteins, and divalent cations interactions are important for many processes in the food industry and human and animal nutrition and health. (bioportfolio.com)
  • We find that Coulomb interactions, both between ionized impurities and with the polarized nanocrystal surface, play a key role in cation exchange. (rug.nl)
  • Can you name the Common Monatoma Cations and Anions? (sporcle.com)
  • Why do atoms of nonmetals form anions while atoms of metals form cations? (answers.com)
  • Nonmetals generally are more electronegative than metals, meaning that they have a stronger pull on their electrons - thus when they form ions, metals give up electrons (forming cations) and nonmetals take up electrons (forming anions). (answers.com)
  • How do cations and anions form? (answers.com)
  • What conclusions can we make about the size of cations neutral atoms and anions? (answers.com)
  • Cations are smaller then neutral atoms and anions are larger. (answers.com)
  • Why are cations smaller and anions larger in radii than their parent atoms? (answers.com)
  • Cations lose electrons, anions gain electrons. (answers.com)
  • Atoms of column 7A become anions when they react with atoms of group 1A elements, which become cations. (answers.com)
  • The cations and anions together form an ionically bonded compound. (answers.com)
  • How do the sizes of cations and anions relate to the atoms they form from? (answers.com)
  • Anions and cations are held together by ionic bonds. (answers.com)
  • are called ions - cations and anions. (answers.com)
  • Atoms of Metals lose electrons to empty their outer shell and become positive ions or cations.Atoms of non-metals gain electrons to fill their outer shell and become negative ions or anions. (answers.com)
  • Gaining or losing electrons atoms become ions (anions or cations). (answers.com)
  • Are the metal atoms cations or anions? (answers.com)
  • How does atomic radius vary with cations anions metals and nonmetals? (answers.com)
  • Any of a group of compounds composed of a cation, in which a central nitrogen atom is joined to four organic groups, and any of various anions, used as antiseptics, solvents, and emulsifying agents. (thefreedictionary.com)
  • The MARGA (Monitor for Aerosols and Gases in Ambient Air) provides a complete system to analyse anions and cations in aerosols, and gases in ambient air. (theengineer.co.uk)
  • cation exchange Process in which cations in solution are exchanged with cations held on the exchange sites of mineral and organic matter , particularly on the surfaces of colloids of clay and humus . (encyclopedia.com)
  • The present invention relates to cation exchange membranes for electrochemical cells, and to their use, especially for the electrolysis of alkali metal chloride solutions to make relatively concentrated alkali metal hydroxide. (google.com)
  • Organoclays with water soluble surfactants were prepared by the traditional cation exchange reaction. (scirp.org)
  • Strong acid styrene cation exchange resin is Styrene divinylbenzene copolymer with a sulfo radical. (tradekey.com)
  • Strong acid styrene cation exchange resin has the feature of high exchange capacity, fast exchanging speed, and good mechanical strength. (tradekey.com)
  • Strong acid styrene cation exchange resin is equivalent to America Amberlite IR-120, Dowex-50, Germany Lewatit-100, and Japan DisionSK-1. (tradekey.com)
  • Strong acid styrene cation exchange resin is mainly used for water softening, desalted water, pure water and high purity water preparation, also used for catalyst and dehydrating agent and wet metallurgy, purification of rare element, pharmaceutical, sugar industry, etc. (tradekey.com)
  • ProteinChip WCX2: is a weak cation exchange array with a carboxylate surface to bind cationic proteins. (bio-medicine.org)
  • The ASTM D4519-compliant cation resin cartridge has a small diameter that allows ion exchange kinetics to achieve lower, more accurate readings than larger cartridges that leach. (mt.com)
  • It is the measurement of the electrolytic conductivity of a liquid sample (water) after that sample has passed through the CE800 Analyzer's ion exchange cation resin columns. (tenlinks.com)
  • Although poorly understood, cation-exchange reactions are increasingly used to dope or transform colloidal semiconductor nanocrystals (quantum dots). (rug.nl)
  • This example uses the phase-equilibrium, cation-exchange, and surface-complexation reaction capabilities of PHREEQC in combination with advective-transport capabilities to model the evolution of water in the Central Oklahoma aquifer. (usgs.gov)
  • Parkhurst and others (1996) provide data from which it is possible to estimate the moles of calcite, dolomite, and cation-exchange sites in the aquifer per liter of water. (usgs.gov)
  • Cation-exchange capacity for the clay ranges from 20 to 50 meq/100 g (milliequivalent per 100 grams), with an average clay content of 30 percent. (usgs.gov)
  • The number of cation-exchange sites was estimated to be 1.0 eq/L. (usgs.gov)
  • Electrophoretic Mobilities and Cation Exchange Capacities of Florida Phosphate Slimes. (cdc.gov)
  • Part of this investigation was to determine the electrophoretic mobilities and cation exchange capacities of the slimes. (cdc.gov)
  • The cation exchange capacities ranged from 17 to 45 milliequivalents per 100 grams of slime solids. (cdc.gov)
  • It binds and transports cations across membranes and uncouples oxidative phosphorylation while inhibiting ATPase of rat liver mitochondria. (bioportfolio.com)
  • Solution of the system of equations defining the multiple equilibria of the proton and cation complexes gives the concentration of each ionic form and a value for the proton stoichiometry for each reaction. (nih.gov)
  • Please note that the groups of cations mentioned/discussed here do not refer to the groups of the periodic table! (wikibooks.org)
  • Cation/proton antiporters (CPAs) play a major role in maintaining living cells' homeostasis. (nature.com)
  • It is thus not surprising that cation/proton antiporters (CPAs) are prevalent in almost all living species. (nature.com)
  • Observations made by Saul Winstein and others suggested that highly delocalized and symmetric intermediates were present in the reactions of various substituted norbornyl cations, evidence for non-classical ions. (wikipedia.org)
  • Here we report on our recent studies of organic radical cation reactions with various ligands. (osti.gov)
  • In this work we investigate the effect of ionic strength and seawater cations on slime formation dynamics and functionality. (nature.com)
  • The potential energy diagram of this model is characterized by a single energy minimum, where the structure of the cation corresponds to the transition state between the two conformers of the classical view. (wikipedia.org)
  • However, many transition metals actually form cations, although there are some exceptions. (answers.com)
  • Cation diffusion facilitator (CDF) proteins are a conserved family of transmembrane transporters that ensure cellular homeostasis of divalent transition metal cations. (bioportfolio.com)
  • The DCC1000e is a degassed cation conductivity system that provides ASTM D4519-compliant conductivity measurements for cycle chemistry monitoring. (mt.com)
  • The DCC1000e System is designed to measure the specific conductivity, cation conductivity and degassed cation conductivity in power plant cycle chemi. (mt.com)
  • Engineers responsible for steam turbine electric power generation systems will find the CE800 Cation Analyzer from Electro-Chemical Devices (ECD) provides a solution to the measurement of conductivity in water, which helps them protect boilers and steam turbines from corrosion. (tenlinks.com)
  • ECD's CE800 Analyzer Series is a family of on-line cation conductivity analyzers that have been designed with ECD's S80 Sensor and uT80 Transmitter. (tenlinks.com)
  • Interacting selectively and non-covalently with cations, charged atoms or groups of atoms with a net positive charge. (fpnotebook.com)
  • This encyclopedic resource provides extensively detailed, state-of-the-art information about cellular organic cation transporters and their relevance to human function and disease. (springer.com)
  • The capillary electrophoresis method for evaluation of cations concentration is based on differential migration and separation of cations in electric field due to the difference in their electrophoretic mobility. (environmental-expert.com)
  • ARTICLE{Raichle76measurementof, author = {M. E. Raichle and R. L. Grubb and J. Eichling and M. M. Ter-pogossian}, title = {Measurement of brain oxygen utilization with radioactive oxygen-15, experimental veri� cation}, journal = {J. Appl. (psu.edu)
  • atoms lose electrons to form cations. (answers.com)
  • Cations are formed when atoms lose electrons and hence are smaller in size than the corresponding atoms. (answers.com)
  • P. Singla, R. Mehta and S. Upadhyay, "Clay Modification by the Use of Organic Cations," Green and Sustainable Chemistry , Vol. 2 No. 1, 2012, pp. 21-25. (scirp.org)
  • article{osti_1358034, title = {The Chemistry of Separations Ligand Degradation by Organic Radical Cations}, author = {Mezyk, Stephen P. and Horne, Gregory P. and Mincher, Bruce J. and Zalupski, Peter R. and Cook, Andrew R. and Wishart, James F.}, abstractNote = {Solvent based extractions of used nuclear fuel use designer ligands in an organic phase extracting ligand complexed metal ions from an acidic aqueous phase. (osti.gov)
  • H] + (deuterium hydrogen cation). (wikipedia.org)
  • Hydrogen-bridged cations are a type of charged species in which a hydrogen atom is simultaneously bonded to two atoms through partial sigma bonds. (wikipedia.org)
  • While best observable in the presence of superacids at room temperature, spectroscopic evidence has suggested that hydrogen-bridged cations exist in ordinary solvents. (wikipedia.org)
  • Figure 1 - Potential Energy Surface (PES) of (a) classical and (b) non-classical view of a hydrogen-bridged cation. (wikipedia.org)
  • Figure 2 - A molecular orbital diagram for open and closed hydrogen bridged cations with carbon is shown above. (wikipedia.org)
  • The first comprehensive theoretical investigation of aromaticity in functionalized corannulene cations of general formula [CH 3 -C 20 H 10 ] + was accomplished. (rsc.org)
  • This innovative text explores the cellular transport of organic cations, from functional and structural properties to pharmacological implications and psychiatric developments. (springer.com)
  • The final chapters delve into the use of animal models for the study of organic cation transporter function and their possible use in environmental cycling of pharmaceutical residues. (springer.com)
  • Generally speaking it is always possible to ionize an atom and produce +1 cation in vacuum, question is, will it survive contact with other elements/ions/molecules? (physicsforums.com)
  • Farm Stays' or 'Hay-cations' are the perfect summer getaway for suburbanites around the country looking for a way to teach their kids where their food comes from, and connect with the land. (foxnews.com)
  • A total of 200 pore volumes of recharge water are advected into the cell and, with each pore volume, the water is equilibrated with the minerals, cation exchanger, and the surfaces in the cell. (usgs.gov)
  • It is now appreciated that the interaction of a cationic group with an aromatic-a cation-π interaction-is much more favorable than an analogous interaction involving a neutral amine ( 10 , 11 ). (pnas.org)
  • Unlike ion pairs, for which any close contact will be energetically favorable, a cation interaction with an aromatic can be attractive or repulsive. (pnas.org)
  • The electrostatic potential surfaces of the aromatics, which control such distinctions ( 1 ), can be complex, and it is difficult to clearly distinguish attractive from repulsive cation-aromatic contacts using geometric criteria alone. (pnas.org)
  • A systematic survey of the Protein Data Bank showed that nearly 8% of the metal cations are naked, more frequently if they can interact only electrostatically with their neighbors. (mdpi.com)
  • A systematic analysis of all naked cations found in the crystal structures deposited with Protein Data Bank was described in the present communication. (mdpi.com)
  • In addition, the cation-π interaction ( 1 - 3 ) is increasingly recognized as an important noncovalent binding interaction relevant to structural biology. (pnas.org)
  • We use density-functional theory and kinetic Monte Carlo simulations to develop a microscopic theory that explains structural, optical, and electronic changes observed experimentally in Ag-cation-exchanged CdSe nanocrystals. (rug.nl)
  • The transient receptor potential (TRP) protein superfamily consists of a diverse group of cation channels that bear structural similarities to Drosophila TRP. (sciencemag.org)
  • Identification and quantitative determination of the analyzed cations is performed by indirect detection measuring UV absorption at 254 or 267 nm wavelength. (environmental-expert.com)
  • Coordination to Divalent Cations by Calcium-Binding Proteins. (bioportfolio.com)
  • Alendronate-Functionalized Poly(2-oxazoline)s with Tunable Affinity for Calcium Cations. (bioportfolio.com)
  • The presence of Mg²+ in close vicinity to the catalytic pocket of bpDNase I reinforces the idea of a cation-assisted hydrolytic mechanism. (nih.gov)
  • Cations are most often metals, as cations are positively charged ions meaning they have lostelectron(s). (answers.com)
  • Some effects of divalent cations on binding and engulfment of several metal oxides and carbon particles are described. (springer.com)
  • How cations can assist DNase I in DNA binding and hydrolysis. (nih.gov)
  • Metal binding to the dynamic cytoplasmic domain of the cation diffusion facilitator (CDF) protein MamM induces a 'locked-in' configuration. (bioportfolio.com)
  • The sidechain of Arg is more likely than that of Lys to be in a cation-π interaction. (pnas.org)
  • Among the aromatics, a strong bias toward Trp is clear, such that over one-fourth of all tryptophans in the data bank experience an energetically significant cation-π interaction. (pnas.org)
  • We also have documented some significant preferences for certain amino acid pairs as partners in a cation-π interaction. (pnas.org)
  • Effect of divalent cations on bovine serum albumin (BSA) and tannic acid interaction and its influence on turbidity and in vitro protein digestibility. (bioportfolio.com)
  • So, instead of feeling like my run was holding me back from seeing the sights, I decided to turn it into a full-blown run-cation: A multi-day vacation that just happens to include running. (huffingtonpost.com)
  • Our goal now would be to distinguish between these three cations. (wikibooks.org)
  • The dihydrogen cation is of great historical and theoretical interest because, having only one electron, the equations of quantum mechanics that describe its structure can be solved in a relatively straightforward way. (wikipedia.org)
  • In the first group of cations, we include Silver(I), Mercury(I)and Lead(II) cations. (wikibooks.org)
  • If a ppt is obtained, group I cations are confirmed. (wikibooks.org)
  • If not, we wll test the solution for the presence of group II cations. (wikibooks.org)