That portion of the nasal mucosa containing the sensory nerve endings for SMELL, located at the dome of each NASAL CAVITY. The yellow-brownish olfactory epithelium consists of OLFACTORY RECEPTOR NEURONS; brush cells; STEM CELLS; and the associated olfactory glands.
Ovoid body resting on the CRIBRIFORM PLATE of the ethmoid bone where the OLFACTORY NERVE terminates. The olfactory bulb contains several types of nerve cells including the mitral cells, on whose DENDRITES the olfactory nerve synapses, forming the olfactory glomeruli. The accessory olfactory bulb, which receives the projection from the VOMERONASAL ORGAN via the vomeronasal nerve, is also included here.
The 1st cranial nerve. The olfactory nerve conveys the sense of smell. It is formed by the axons of OLFACTORY RECEPTOR NEURONS which project from the olfactory epithelium (in the nasal epithelium) to the OLFACTORY BULB.
Neurons in the OLFACTORY EPITHELIUM with proteins (RECEPTORS, ODORANT) that bind, and thus detect, odorants. These neurons send their DENDRITES to the surface of the epithelium with the odorant receptors residing in the apical non-motile cilia. Their unmyelinated AXONS synapse in the OLFACTORY BULB of the BRAIN.
The mucous lining of the NASAL CAVITY, including lining of the nostril (vestibule) and the OLFACTORY MUCOSA. Nasal mucosa consists of ciliated cells, GOBLET CELLS, brush cells, small granule cells, basal cells (STEM CELLS) and glands containing both mucous and serous cells.
The ability to detect scents or odors, such as the function of OLFACTORY RECEPTOR NEURONS.
The volatile portions of substances perceptible by the sense of smell. (Grant & Hackh's Chemical Dictionary, 5th ed)
A ubiquitous, cytoplasmic protein found in mature OLFACTORY RECEPTOR NEURONS of all VERTEBRATES. It is a modulator of the olfactory SIGNAL TRANSDUCTION PATHWAY.
Burrowing, chiefly nocturnal mammals of the family Dasypodidae having bodies and heads encased in small bony plates. They are widely distributed in the warmer parts of the Americas.
Proteins, usually projecting from the cilia of olfactory receptor neurons, that specifically bind odorant molecules and trigger responses in the neurons. The large number of different odorant receptors appears to arise from several gene families or subfamilies rather than from DNA rearrangement.
Lining of the INTESTINES, consisting of an inner EPITHELIUM, a middle LAMINA PROPRIA, and an outer MUSCULARIS MUCOSAE. In the SMALL INTESTINE, the mucosa is characterized by a series of folds and abundance of absorptive cells (ENTEROCYTES) with MICROVILLI.
The proximal portion of the respiratory passages on either side of the NASAL SEPTUM. Nasal cavities, extending from the nares to the NASOPHARYNX, are lined with ciliated NASAL MUCOSA.
Inorganic compounds that contain tin as an integral part of the molecule.
An antifungal agent used in the treatment of TINEA infections.
Lining of the STOMACH, consisting of an inner EPITHELIUM, a middle LAMINA PROPRIA, and an outer MUSCULARIS MUCOSAE. The surface cells produce MUCUS that protects the stomach from attack by digestive acid and enzymes. When the epithelium invaginates into the LAMINA PROPRIA at various region of the stomach (CARDIA; GASTRIC FUNDUS; and PYLORUS), different tubular gastric glands are formed. These glands consist of cells that secrete mucus, enzymes, HYDROCHLORIC ACID, or hormones.
'Benzene derivatives' are organic compounds that contain a benzene ring as the core structure, with various functional groups attached to it, and can have diverse chemical properties and uses, including as solvents, intermediates in chemical synthesis, and pharmaceuticals.
Specialized afferent neurons capable of transducing sensory stimuli into NERVE IMPULSES to be transmitted to the CENTRAL NERVOUS SYSTEM. Sometimes sensory receptors for external stimuli are called exteroceptors; for internal stimuli are called interoceptors and proprioceptors.
Tumors or cancer of the NOSE.
Chlorobenzenes are organic compounds consisting of a benzene ring substituted with one or more chlorine atoms, used as solvents, refrigerants, and intermediates in the production of other chemicals, but with limited use due to environmental and health concerns.
Lining of the ORAL CAVITY, including mucosa on the GUMS; the PALATE; the LIP; the CHEEK; floor of the mouth; and other structures. The mucosa is generally a nonkeratinized stratified squamous EPITHELIUM covering muscle, bone, or glands but can show varying degree of keratinization at specific locations.
Synthetic or naturally occurring substances related to coumarin, the delta-lactone of coumarinic acid.
A large group of cytochrome P-450 (heme-thiolate) monooxygenases that complex with NAD(P)H-FLAVIN OXIDOREDUCTASE in numerous mixed-function oxidations of aromatic compounds. They catalyze hydroxylation of a broad spectrum of substrates and are important in the metabolism of steroids, drugs, and toxins such as PHENOBARBITAL, carcinogens, and insecticides.
Loss of or impaired ability to smell. This may be caused by OLFACTORY NERVE DISEASES; PARANASAL SINUS DISEASES; viral RESPIRATORY TRACT INFECTIONS; CRANIOCEREBRAL TRAUMA; SMOKING; and other conditions.
A thioureylene antithyroid agent that inhibits the formation of thyroid hormones by interfering with the incorporation of iodine into tyrosyl residues of thyroglobulin. This is done by interfering with the oxidation of iodide ion and iodotyrosyl groups through inhibition of the peroxidase enzyme.
Pesticides used to destroy unwanted vegetation, especially various types of weeds, grasses (POACEAE), and woody plants. Some plants develop HERBICIDE RESISTANCE.
The chemical alteration of an exogenous substance by or in a biological system. The alteration may inactivate the compound or it may result in the production of an active metabolite of an inactive parent compound. The alterations may be divided into METABOLIC DETOXICATION, PHASE I and METABOLIC DETOXICATION, PHASE II.
Widely distributed enzymes that carry out oxidation-reduction reactions in which one atom of the oxygen molecule is incorporated into the organic substrate; the other oxygen atom is reduced and combined with hydrogen ions to form water. They are also known as monooxygenases or hydroxylases. These reactions require two substrates as reductants for each of the two oxygen atoms. There are different classes of monooxygenases depending on the type of hydrogen-providing cosubstrate (COENZYMES) required in the mixed-function oxidation.
Derivatives of acetamide that are used as solvents, as mild irritants, and in organic synthesis.
Histochemical localization of immunoreactive substances using labeled antibodies as reagents.
A superfamily of hundreds of closely related HEMEPROTEINS found throughout the phylogenetic spectrum, from animals, plants, fungi, to bacteria. They include numerous complex monooxygenases (MIXED FUNCTION OXYGENASES). In animals, these P-450 enzymes serve two major functions: (1) biosynthesis of steroids, fatty acids, and bile acids; (2) metabolism of endogenous and a wide variety of exogenous substrates, such as toxins and drugs (BIOTRANSFORMATION). They are classified, according to their sequence similarities rather than functions, into CYP gene families (>40% homology) and subfamilies (>59% homology). For example, enzymes from the CYP1, CYP2, and CYP3 gene families are responsible for most drug metabolism.
Traumatic injuries to the OLFACTORY NERVE. It may result in various olfactory dysfunction including a complete loss of smell.
The making of a radiograph of an object or tissue by recording on a photographic plate the radiation emitted by radioactive material within the object. (Dorland, 27th ed)
Inbred C57BL mice are a strain of laboratory mice that have been produced by many generations of brother-sister matings, resulting in a high degree of genetic uniformity and homozygosity, making them widely used for biomedical research, including studies on genetics, immunology, cancer, and neuroscience.
Azoles of two nitrogens at the 1,2 positions, next to each other, in contrast with IMIDAZOLES in which they are at the 1,3 positions.
Artifactual vesicles formed from the endoplasmic reticulum when cells are disrupted. They are isolated by differential centrifugation and are composed of three structural features: rough vesicles, smooth vesicles, and ribosomes. Numerous enzyme activities are associated with the microsomal fraction. (Glick, Glossary of Biochemistry and Molecular Biology, 1990; from Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)
Accumulation of a drug or chemical substance in various organs (including those not relevant to its pharmacologic or therapeutic action). This distribution depends on the blood flow or perfusion rate of the organ, the ability of the drug to penetrate organ membranes, tissue specificity, protein binding. The distribution is usually expressed as tissue to plasma ratios.
The non-neuronal cells of the nervous system. They not only provide physical support, but also respond to injury, regulate the ionic and chemical composition of the extracellular milieu, participate in the BLOOD-BRAIN BARRIER and BLOOD-RETINAL BARRIER, form the myelin insulation of nervous pathways, guide neuronal migration during development, and exchange metabolites with neurons. Neuroglia have high-affinity transmitter uptake systems, voltage-dependent and transmitter-gated ion channels, and can release transmitters, but their role in signaling (as in many other functions) is unclear.
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.
A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.
A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.
A malignant olfactory neuroblastoma arising from the olfactory epithelium of the superior nasal cavity and cribriform plate. It is uncommon (3% of nasal tumors) and rarely is associated with the production of excess hormones (e.g., SIADH, Cushing Syndrome). It has a high propensity for multiple local recurrences and bony metastases. (From Holland et al., Cancer Medicine, 3rd ed, p1245; J Laryngol Otol 1998 Jul;112(7):628-33)
An accessory chemoreceptor organ that is separated from the main OLFACTORY MUCOSA. It is situated at the base of nasal septum close to the VOMER and NASAL BONES. It forwards chemical signals (such as PHEROMONES) to the CENTRAL NERVOUS SYSTEM, thus influencing reproductive and social behavior. In humans, most of its structures except the vomeronasal duct undergo regression after birth.
Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.
Paired sense organs connected to the anterior segments of ARTHROPODS that help them navigate through the environment.
An increase in the rate of synthesis of an enzyme due to the presence of an inducer which acts to derepress the gene responsible for enzyme synthesis.
The pathological process occurring in cells that are dying from irreparable injuries. It is caused by the progressive, uncontrolled action of degradative ENZYMES, leading to MITOCHONDRIAL SWELLING, nuclear flocculation, and cell lysis. It is distinct it from APOPTOSIS, which is a normal, regulated cellular process.

Functional identification and reconstitution of an odorant receptor in single olfactory neurons. (1/735)

The olfactory system is remarkable in its capacity to discriminate a wide range of odorants through a series of transduction events initiated in olfactory receptor neurons. Each olfactory neuron is expected to express only a single odorant receptor gene that belongs to the G protein coupled receptor family. The ligand-receptor interaction, however, has not been clearly characterized. This study demonstrates the functional identification of olfactory receptor(s) for specific odorant(s) from single olfactory neurons by a combination of Ca2+-imaging and reverse transcription-coupled PCR analysis. First, a candidate odorant receptor was cloned from a single tissue-printed olfactory neuron that displayed odorant-induced Ca2+ increase. Next, recombinant adenovirus-mediated expression of the isolated receptor gene was established in the olfactory epithelium by using green fluorescent protein as a marker. The infected neurons elicited external Ca2+ entry when exposed to the odorant that originally was used to identify the receptor gene. Experiments performed to determine ligand specificity revealed that the odorant receptor recognized specific structural motifs within odorant molecules. The odorant receptor-mediated signal transduction appears to be reconstituted by this two-step approach: the receptor screening for given odorant(s) from single neurons and the functional expression of the receptor via recombinant adenovirus. The present approach should enable us to examine not only ligand specificity of an odorant receptor but also receptor specificity and diversity for a particular odorant of interest.  (+info)

Chemoattraction and chemorepulsion of olfactory bulb axons by different secreted semaphorins. (2/735)

During development, growth cones can be guided at a distance by diffusible factors, which are attractants and/or repellents. The semaphorins are the largest family of repulsive axon guidance molecules. Secreted semaphorins bind neuropilin receptors and repel sensory, sympathetic, motor, and forebrain axons. We found that in rat embryos, the olfactory epithelium releases a diffusible factor that repels olfactory bulb axons. In addition, Sema A and Sema IV, but not Sema III, Sema E, or Sema H, are able to orient in vitro the growth of olfactory bulb axons; Sema IV has a strong repulsive action, whereas Sema A appears to attract those axons. The expression patterns of sema A and sema IV in the developing olfactory system confirm that they may play a cooperative role in the formation of the lateral olfactory tract. This also represents a further evidence for a chemoattractive function of secreted semaphorins.  (+info)

A novel 45 kDa secretory protein from rat olfactory epithelium: primary structure and localisation. (3/735)

cDNA clones encoding the 45 kDa protein were isolated from a rat olfactory epithelium cDNA library and their inserts were sequenced. The reconstructed protein sequence comprises 400 amino acids with a calculated molecular mass of 46,026 Da. A homology was revealed between the amino acid sequence of the 45 kDa protein and the proteins involved in the transfer of hydrophobic ligands. Using in situ hybridisation, the 45 kDa protein mRNA expression was detected in the layer of supportive cells of olfactory epithelium, apical region of trachea, surface layer of the ciliated bronchial epithelium in lung and in skin epidermis.  (+info)

Localization and comparative toxicity of methylsulfonyl-2,5- and 2,6-dichlorobenzene in the olfactory mucosa of mice. (4/735)

Several methylsulfonyl (MeSO2) metabolites formed from chlorinated aromatic hydrocarbons have been identified in human milk, lung, and body fat, as well as in the tissues of Baltic grey seals and arctic polar bears. The tissue localization and nasal toxicity of two methylsulfonyl-substituted dichlorobenzenes (diCl-MeSO2-B), with the chlorine atoms in the 2,5-, and 2,6- positions, were investigated in female NMRI and C57B1 mice. Using tape-section autoradiography, animals dosed i.v. with 14C-labeled 2,5-, or 2,6-(diCl-MeSO2-B) showed a preferential uptake of radioactivity in the olfactory mucosa and the tracheobronchial epithelium. Histopathology showed that 2,6-(diCl-MeSO2-B) is a potent toxicant that induces necrosis in the olfactory mucosa following a single dose as low as 4 mg/kg (i.p. injection), whereas 2,5-(diCl-MeSO2-B) induced no signs of toxicity in the olfactory mucosa at doses as high as 130 mg/kg (i.p. injection). Necrosis of the Bowman's glands was the first sign of 2,6-(diCl-MeSO2-B)-induced toxicity followed by degeneration of the neuroepithelium, which implies that the Bowman's gland may be the primary site of toxicity and degeneration of the neuroepithelium may be a secondary effect. Administration of the parent compounds, 1,3-dichlorobenzene and 1,4-dichlorobenzene, or the chlorinated analog 1,2,3-trichlorobenzene (85, 85, and 105 mg/kg, respectively; i.p. injection), induced no signs of toxicity in the olfactory mucosa. These and previous results suggest that 2,6-positioned chlorine atoms and an electron withdrawing substituent in the primary position is an arrangement that predisposes for toxicity in the olfactory mucosa.  (+info)

Identification and localisation of glycoconjugates in the olfactory mucosa of the armadillo Chaetophractus villosus. (5/735)

Conventional histochemistry and the binding patterns of 22 biotinylated lectins were examined for characterisation of glycoconjugates in the components of the olfactory mucosa of the armadillo Chaetophractus villosus. The mucous lining the olfactory epithelium showed binding sites for DSL, WGA, STL, LEL, PHA-E and JAC. Only the basilar processes of the supporting cells stained for Con-A and S-Con A. The olfactory receptor neurons stained with LEL, LCA, Con A, S-Con A, JAC and PNA. The layer of basal cells did not react with any of the lectins studied. Bowman's glands in the lamina propria showed subpopulations of acinar cells reacting with SBA, S-WGA, WGA, STL, Con A, PSA, PNA, SJA, VVA, JAC and S-Con A, but in our optical studies with lectins we were unable to differentiate between mucous and serous cells in the way that is possible on electron microscopy. The ducts of Bowman's glands were labelled with S-WGA, STL, LEL, PHA-E, BSL-I and JAC. This histochemical study on the glycoconjugates of the olfactory mucosa in the order Xenarthra provides a basis for further experimental investigations.  (+info)

Evidence for site-specific bioactivation of alachlor in the olfactory mucosa of the Long-Evans rat. (6/735)

Alachlor (2-chloro-2',6'-diethyl-N-[methoxymethyl]-acetanilide) is a restricted-use chloracetanilide herbicide which has been shown previously to produce a dose-dependent incidence of olfactory mucosal tumors in rats following chronic dietary exposure. However, the mechanism of alachlor carcinogenicity is poorly understood. Alachlor was administered i.p. to male Long-Evans rats for up to 28 days at doses that are carcinogenic in chronic studies in order to study olfactory lesion development and alterations in cell proliferation. Neither treatment-related olfactory mucosal lesions nor regenerative cell proliferation, as assessed with BrdU labeling, was detected. In vitro genotoxicity studies using Salmonella typhimurium strain TA100 showed that alachlor was non-mutagenic in the absence of metabolic activation. When pre-incubated with an olfactory mucosal S9 activation system, alachlor induced a weak, dose-dependent mutagenic response at 500-1250 micrograms/plate, with toxicity at higher doses. In contrast, an S9 activation system derived from nasal respiratory mucosa, the tissue physically juxtaposed with the olfactory mucosa but reportedly not susceptible to alachlor-induced tumors, did not produce a mutagenic response for alachlor or the positive control. Thus, this result suggested site-specificity of alachlor activation consistent with the target site of carcinogenicity. The mutagenicity of alachlor to Salmonella, in the presence of an olfactory mucosal-activating system, was confirmed by a limited positive response in the mouse lymphoma assay. Here there were increases in small colony mutants (indicative of chromosomal effects) as well as large colony mutants (which reflect gene mutations). This study suggests that target tissue bioactivation of alachlor results in the formation of one or more mutagenic metabolite(s), which may be critical in alachlor-induced nasal tumorigenesis.  (+info)

An olfactory sensory neuron line, odora, properly targets olfactory proteins and responds to odorants. (7/735)

The site for interactions between the nervous system and much of the chemical world is in the olfactory sensory neuron (OSN). Odorant receptor proteins (ORPs) are postulated to mediate these interactions. However, the function of most ORPs has not been demonstrated in vivo or in vitro. For this and other reasons, we created a conditionally immortalized cell line derived from the OSN lineage, which we term odora. Odora cells, under control conditions, are phenotypically similar to the OSN progenitor, the globose basal cell. After differentiation, odora cells more closely resemble OSNs. Differentiated odora cells express neuronal and olfactory markers, including components of the olfactory signal transduction pathway. Unlike other cell lines, they also efficiently target exogenous ORPs to their surface. Strikingly, differentiated odora cells expressing ORPs respond to odorants, as measured by an influx of calcium. In particular, cells expressing one ORP demonstrate a specific response to only one type of tested odorant. Odora cells, therefore, are ideal models to examine the genesis and function of olfactory sensory neurons.  (+info)

Olfactory neurons expressing closely linked and homologous odorant receptor genes tend to project their axons to neighboring glomeruli on the olfactory bulb. (8/735)

We have characterized two separate odorant receptor (OR) gene clusters to examine how olfactory neurons expressing closely linked and homologous OR genes project their axons to the olfactory bulb. Murine OR genes, MOR28, MOR10, and MOR83, share 75-95% similarities in the amino acid sequences and are tightly linked on chromosome 14. In situ hybridization has demonstrated that the three genes are expressed in the same zone, at the most dorsolateral and ventromedial portions of the olfactory epithelium, and are rarely expressed simultaneously in individual neurons. Furthermore, we have found that olfactory neurons expressing MOR28, MOR10, or MOR83 project their axons to very close but distinct subsets of glomeruli on the medial and lateral sides of the olfactory bulb. Similar results have been obtained with another murine OR gene cluster for A16 and MOR18 on chromosome 2, sharing 91% similarity in the amino acid sequences. These results may indicate an intriguing possibility that olfactory neurons expressing homologous OR genes within a cluster tend to converge their axons to proximal but distinct subsets of glomeruli. These lines of study will shed light on the molecular basis of topographical projection of olfactory neurons to the olfactory bulb.  (+info)

The olfactory mucosa is a specialized mucous membrane that is located in the upper part of the nasal cavity, near the septum and the superior turbinate. It contains the olfactory receptor neurons, which are responsible for the sense of smell. These neurons have hair-like projections called cilia that are covered in a mucus layer, which helps to trap and identify odor molecules present in the air we breathe. The olfactory mucosa also contains supporting cells, blood vessels, and nerve fibers that help to maintain the health and function of the olfactory receptor neurons. Damage to the olfactory mucosa can result in a loss of smell or anosmia.

The olfactory bulb is the primary center for the sense of smell in the brain. It's a structure located in the frontal part of the brain, specifically in the anterior cranial fossa, and is connected to the nasal cavity through tiny holes called the cribriform plates. The olfactory bulb receives signals from olfactory receptors in the nose that detect different smells, processes this information, and then sends it to other areas of the brain for further interpretation and perception of smell.

The olfactory nerve, also known as the first cranial nerve (I), is a specialized sensory nerve that is responsible for the sense of smell. It consists of thin, delicate fibers called olfactory neurons that are located in the upper part of the nasal cavity. These neurons have hair-like structures called cilia that detect and transmit information about odors to the brain.

The olfactory nerve has two main parts: the peripheral process and the central process. The peripheral process extends from the olfactory neuron to the nasal cavity, where it picks up odor molecules. These molecules bind to receptors on the cilia, which triggers an electrical signal that travels along the nerve fiber to the brain.

The central process of the olfactory nerve extends from the olfactory bulb, a structure at the base of the brain, to several areas in the brain involved in smell and memory, including the amygdala, hippocampus, and thalamus. Damage to the olfactory nerve can result in a loss of smell (anosmia) or distorted smells (parosmia).

Olfactory receptor neurons (ORNs) are specialized sensory nerve cells located in the olfactory epithelium, a patch of tissue inside the nasal cavity. These neurons are responsible for detecting and transmitting information about odors to the brain. Each ORN expresses only one type of olfactory receptor protein, which is specific to certain types of odor molecules. When an odor molecule binds to its corresponding receptor, it triggers a signal transduction pathway that generates an electrical impulse in the neuron. This impulse is then transmitted to the brain via the olfactory nerve, where it is processed and interpreted as a specific smell. ORNs are continuously replaced throughout an individual's lifetime due to their exposure to environmental toxins and other damaging agents.

Nasal mucosa refers to the mucous membrane that lines the nasal cavity. It is a delicate, moist, and specialized tissue that contains various types of cells including epithelial cells, goblet cells, and glands. The primary function of the nasal mucosa is to warm, humidify, and filter incoming air before it reaches the lungs.

The nasal mucosa produces mucus, which traps dust, allergens, and microorganisms, preventing them from entering the respiratory system. The cilia, tiny hair-like structures on the surface of the epithelial cells, help move the mucus towards the back of the throat, where it can be swallowed or expelled.

The nasal mucosa also contains a rich supply of blood vessels and immune cells that help protect against infections and inflammation. It plays an essential role in the body's defense system by producing antibodies, secreting antimicrobial substances, and initiating local immune responses.

In medical terms, the sense of smell is referred to as olfaction. It is the ability to detect and identify different types of chemicals in the air through the use of the olfactory system. The olfactory system includes the nose, nasal passages, and the olfactory bulbs located in the brain.

When a person inhales air containing volatile substances, these substances bind to specialized receptor cells in the nasal passage called olfactory receptors. These receptors then transmit signals to the olfactory bulbs, which process the information and send it to the brain's limbic system, including the hippocampus and amygdala, as well as to the cortex. The brain interprets these signals and identifies the various scents or smells.

Impairment of the sense of smell can occur due to various reasons such as upper respiratory infections, sinusitis, nasal polyps, head trauma, or neurodegenerative disorders like Parkinson's disease and Alzheimer's disease. Loss of smell can significantly impact a person's quality of life, including their ability to taste food, detect dangers such as smoke or gas leaks, and experience emotions associated with certain smells.

In the context of medicine, "odors" refer to smells or scents that are produced by certain medical conditions, substances, or bodily functions. These odors can sometimes provide clues about underlying health issues. For example, sweet-smelling urine could indicate diabetes, while foul-smelling breath might suggest a dental problem or gastrointestinal issue. However, it's important to note that while odors can sometimes be indicative of certain medical conditions, they are not always reliable diagnostic tools and should be considered in conjunction with other symptoms and medical tests.

The olfactory marker protein (OMP) is a specific type of protein that is primarily found in the olfactory sensory neurons of the nose. These neurons are responsible for detecting and transmitting information about odors to the brain. The OMP plays a crucial role in the function of these neurons, as it helps to maintain their structure and stability. It also contributes to the process of odor detection by helping to speed up the transmission of signals from the olfactory receptors to the brain.

The presence of OMP is often used as a marker for mature olfactory sensory neurons, as it is not typically found in other types of cells. Additionally, changes in the expression levels of OMP have been associated with various neurological conditions, such as Alzheimer's disease and Parkinson's disease, making it a potential target for diagnostic and therapeutic purposes.

An armadillo is not a medical condition or term. It is a type of mammal that is native to the Americas, known for its distinctive armor-like shell. If you have any questions about a specific medical condition or topic, I would be happy to help if you could provide more information.

Odorant receptors are a type of G protein-coupled receptor (GPCR) that are primarily found in the cilia of olfactory sensory neurons in the nose. These receptors are responsible for detecting and transmitting information about odorants, or volatile molecules that we perceive as smells.

Each odorant receptor can bind to a specific set of odorant molecules, and when an odorant binds to its corresponding receptor, it triggers a signaling cascade that ultimately leads to the generation of an electrical signal in the olfactory sensory neuron. This signal is then transmitted to the brain, where it is processed and interpreted as a particular smell.

There are thought to be around 400 different types of odorant receptors in humans, each with its own unique binding profile. The combinatorial coding of these receptors allows for the detection and discrimination of a vast array of different smells, from sweet to sour, floral to fruity, and everything in between.

Overall, the ability to detect and respond to odorants is critical for many important functions, including the identification of food, mates, and potential dangers in the environment.

The intestinal mucosa is the innermost layer of the intestines, which comes into direct contact with digested food and microbes. It is a specialized epithelial tissue that plays crucial roles in nutrient absorption, barrier function, and immune defense. The intestinal mucosa is composed of several cell types, including absorptive enterocytes, mucus-secreting goblet cells, hormone-producing enteroendocrine cells, and immune cells such as lymphocytes and macrophages.

The surface of the intestinal mucosa is covered by a single layer of epithelial cells, which are joined together by tight junctions to form a protective barrier against harmful substances and microorganisms. This barrier also allows for the selective absorption of nutrients into the bloodstream. The intestinal mucosa also contains numerous lymphoid follicles, known as Peyer's patches, which are involved in immune surveillance and defense against pathogens.

In addition to its role in absorption and immunity, the intestinal mucosa is also capable of producing hormones that regulate digestion and metabolism. Dysfunction of the intestinal mucosa can lead to various gastrointestinal disorders, such as inflammatory bowel disease, celiac disease, and food allergies.

The nasal cavity is the air-filled space located behind the nose, which is divided into two halves by the nasal septum. It is lined with mucous membrane and is responsible for several functions including respiration, filtration, humidification, and olfaction (smell). The nasal cavity serves as an important part of the upper respiratory tract, extending from the nares (nostrils) to the choanae (posterior openings of the nasal cavity that lead into the pharynx). It contains specialized structures such as turbinate bones, which help to warm, humidify and filter incoming air.

Tin compounds refer to chemical substances that contain tin (Sn) combined with one or more other elements. Tin can form various types of compounds, including oxides, sulfides, halides, and organometallic compounds. These compounds have different properties and uses depending on the other element(s) they are combined with.

For example:

* Tin (IV) oxide (SnO2) is a white powder used as an opacifying agent in glass and ceramics, as well as a component in some types of batteries.
* Tin (II) sulfide (SnS) is a black or brown solid used in the manufacture of some types of semiconductors.
* Tin (IV) chloride (SnCl4) is a colorless liquid used as a catalyst in the production of polyvinyl chloride (PVC) and other plastics.
* Organotin compounds, such as tributyltin (TBT), are used as biocides and antifouling agents in marine paints. However, they have been found to be toxic to aquatic life and are being phased out in many countries.

Griseofulvin is an antifungal medication used to treat various fungal infections, including those affecting the skin, hair, and nails. It works by inhibiting the growth of fungi, particularly dermatophytes, which cause these infections. Griseofulvin can be obtained through a prescription and is available in oral (by mouth) and topical (on the skin) forms.

The primary mechanism of action for griseofulvin involves binding to tubulin, a protein necessary for fungal cell division. This interaction disrupts the formation of microtubules, which are crucial for the fungal cell's structural integrity and growth. As a result, the fungi cannot grow and multiply, allowing the infected tissue to heal and the infection to resolve.

Common side effects associated with griseofulvin use include gastrointestinal symptoms (e.g., nausea, vomiting, diarrhea), headache, dizziness, and skin rashes. It is essential to follow the prescribing physician's instructions carefully when taking griseofulvin, as improper usage may lead to reduced effectiveness or increased risk of side effects.

It is important to note that griseofulvin has limited use in modern medicine due to the development of newer and more effective antifungal agents. However, it remains a valuable option for specific fungal infections, particularly those resistant to other treatments.

Gastric mucosa refers to the innermost lining of the stomach, which is in contact with the gastric lumen. It is a specialized mucous membrane that consists of epithelial cells, lamina propria, and a thin layer of smooth muscle. The surface epithelium is primarily made up of mucus-secreting cells (goblet cells) and parietal cells, which secrete hydrochloric acid and intrinsic factor, and chief cells, which produce pepsinogen.

The gastric mucosa has several important functions, including protection against self-digestion by the stomach's own digestive enzymes and hydrochloric acid. The mucus layer secreted by the epithelial cells forms a physical barrier that prevents the acidic contents of the stomach from damaging the underlying tissues. Additionally, the bicarbonate ions secreted by the surface epithelial cells help neutralize the acidity in the immediate vicinity of the mucosa.

The gastric mucosa is also responsible for the initial digestion of food through the action of hydrochloric acid and pepsin, an enzyme that breaks down proteins into smaller peptides. The intrinsic factor secreted by parietal cells plays a crucial role in the absorption of vitamin B12 in the small intestine.

The gastric mucosa is constantly exposed to potential damage from various factors, including acid, pepsin, and other digestive enzymes, as well as mechanical stress due to muscle contractions during digestion. To maintain its integrity, the gastric mucosa has a remarkable capacity for self-repair and regeneration. However, chronic exposure to noxious stimuli or certain medical conditions can lead to inflammation, erosions, ulcers, or even cancer of the gastric mucosa.

Benzene derivatives are chemical compounds that are derived from benzene, which is a simple aromatic hydrocarbon with the molecular formula C6H6. Benzene has a planar, hexagonal ring structure, and its derivatives are formed by replacing one or more of the hydrogen atoms in the benzene molecule with other functional groups.

Benzene derivatives have a wide range of applications in various industries, including pharmaceuticals, dyes, plastics, and explosives. Some common examples of benzene derivatives include toluene, xylene, phenol, aniline, and nitrobenzene. These compounds can have different physical and chemical properties depending on the nature and position of the substituents attached to the benzene ring.

It is important to note that some benzene derivatives are known to be toxic or carcinogenic, and their production, use, and disposal must be carefully regulated to ensure safety and protect public health.

Sensory receptor cells are specialized structures that convert physical stimuli from our environment into electrical signals, which are then transmitted to the brain for interpretation. These receptors can be found in various tissues throughout the body and are responsible for detecting sensations such as touch, pressure, temperature, taste, and smell. They can be classified into two main types: exteroceptors, which respond to stimuli from the external environment, and interoceptors, which react to internal conditions within the body. Examples of sensory receptor cells include hair cells in the inner ear, photoreceptors in the eye, and taste buds on the tongue.

Nose neoplasms refer to abnormal growths or tumors in the nasal cavity or paranasal sinuses. These growths can be benign (non-cancerous) or malignant (cancerous). Benign neoplasms are typically slow-growing and do not spread to other parts of the body, while malignant neoplasms can invade surrounding tissues and have the potential to metastasize.

Nose neoplasms can cause various symptoms such as nasal congestion, nosebleeds, difficulty breathing through the nose, loss of smell, facial pain or numbness, and visual changes if they affect the eye. The diagnosis of nose neoplasms usually involves a combination of physical examination, imaging studies (such as CT or MRI scans), and biopsy to determine the type and extent of the growth. Treatment options depend on the type, size, location, and stage of the neoplasm and may include surgery, radiation therapy, chemotherapy, or a combination of these approaches.

Chlorobenzenes are a group of chemical compounds that consist of a benzene ring (a cyclic structure with six carbon atoms in a hexagonal arrangement) substituted with one or more chlorine atoms. They have the general formula C6H5Clx, where x represents the number of chlorine atoms attached to the benzene ring.

Chlorobenzenes are widely used as industrial solvents, fumigants, and intermediates in the production of other chemicals. Some common examples of chlorobenzenes include monochlorobenzene (C6H5Cl), dichlorobenzenes (C6H4Cl2), trichlorobenzenes (C6H3Cl3), and tetrachlorobenzenes (C6H2Cl4).

Exposure to chlorobenzenes can occur through inhalation, skin contact, or ingestion. They are known to be toxic and can cause a range of health effects, including irritation of the eyes, skin, and respiratory tract, headaches, dizziness, nausea, and vomiting. Long-term exposure has been linked to liver and kidney damage, neurological effects, and an increased risk of cancer.

It is important to handle chlorobenzenes with care and follow appropriate safety precautions to minimize exposure. If you suspect that you have been exposed to chlorobenzenes, seek medical attention immediately.

The mouth mucosa refers to the mucous membrane that lines the inside of the mouth, also known as the oral mucosa. It covers the tongue, gums, inner cheeks, palate, and floor of the mouth. This moist tissue is made up of epithelial cells, connective tissue, blood vessels, and nerve endings. Its functions include protecting the underlying tissues from physical trauma, chemical irritation, and microbial infections; aiding in food digestion by producing enzymes; and providing sensory information about taste, temperature, and texture.

Coumarins are a class of organic compounds that occur naturally in certain plants, such as sweet clover and tonka beans. They have a characteristic aroma and are often used as fragrances in perfumes and flavorings in food products. In addition to their use in consumer goods, coumarins also have important medical applications.

One of the most well-known coumarins is warfarin, which is a commonly prescribed anticoagulant medication used to prevent blood clots from forming or growing larger. Warfarin works by inhibiting the activity of vitamin K-dependent clotting factors in the liver, which helps to prolong the time it takes for blood to clot.

Other medical uses of coumarins include their use as anti-inflammatory agents and antimicrobial agents. Some coumarins have also been shown to have potential cancer-fighting properties, although more research is needed in this area.

It's important to note that while coumarins have many medical uses, they can also be toxic in high doses. Therefore, it's essential to use them only under the guidance of a healthcare professional.

Aryl hydrocarbon hydroxylases (AHH) are a group of enzymes that play a crucial role in the metabolism of various aromatic and heterocyclic compounds, including potentially harmful substances such as polycyclic aromatic hydrocarbons (PAHs) and dioxins. These enzymes are primarily located in the endoplasmic reticulum of cells, particularly in the liver, but can also be found in other tissues.

The AHH enzymes catalyze the addition of a hydroxyl group (-OH) to the aromatic ring structure of these compounds, which is the first step in their biotransformation and eventual elimination from the body. This process can sometimes lead to the formation of metabolites that are more reactive and potentially toxic than the original compound. Therefore, the overall impact of AHH enzymes on human health is complex and depends on various factors, including the specific compounds being metabolized and individual genetic differences in enzyme activity.

Olfaction disorders, also known as smell disorders, refer to conditions that affect the ability to detect or interpret odors. These disorders can be categorized into two main types:

1. Anosmia: This is a complete loss of the sense of smell. It can be caused by various factors such as nasal polyps, sinus infections, head injuries, and degenerative diseases like Alzheimer's and Parkinson's.
2. Hyposmia: This is a reduced ability to detect odors. Like anosmia, it can also be caused by similar factors including aging and exposure to certain chemicals.

Other olfaction disorders include parosmia, which is a distortion of smell where individuals may perceive a smell as being different from its original scent, and phantosmia, which is the perception of a smell that isn't actually present.

Methimazole is an anti-thyroid medication that is primarily used to treat hyperthyroidism, a condition in which the thyroid gland produces excessive amounts of thyroid hormones. It works by inhibiting the enzyme thyroperoxidase, which is essential for the production of thyroid hormones. By blocking this enzyme, methimazole reduces the amount of thyroid hormones produced by the thyroid gland, helping to restore normal thyroid function.

Methimazole is available in oral tablet form and is typically taken two to three times a day. Common side effects of methimazole include nausea, vomiting, skin rashes, and joint pain. In rare cases, it can cause more serious side effects such as liver damage or agranulocytosis (a severe decrease in white blood cell count).

It is important to note that methimazole should only be used under the close supervision of a healthcare provider, as regular monitoring of thyroid function and potential side effects is necessary. Additionally, it may take several weeks or months of treatment with methimazole before thyroid function returns to normal.

Herbicides are a type of pesticide used to control or kill unwanted plants, also known as weeds. They work by interfering with the growth processes of the plant, such as inhibiting photosynthesis, disrupting cell division, or preventing the plant from producing certain essential proteins.

Herbicides can be classified based on their mode of action, chemical composition, and the timing of their application. Some herbicides are selective, meaning they target specific types of weeds while leaving crops unharmed, while others are non-selective and will kill any plant they come into contact with.

It's important to use herbicides responsibly and according to the manufacturer's instructions, as they can have negative impacts on the environment and human health if not used properly.

Biotransformation is the metabolic modification of a chemical compound, typically a xenobiotic (a foreign chemical substance found within an living organism), by a biological system. This process often involves enzymatic conversion of the parent compound to one or more metabolites, which may be more or less active, toxic, or mutagenic than the original substance.

In the context of pharmacology and toxicology, biotransformation is an important aspect of drug metabolism and elimination from the body. The liver is the primary site of biotransformation, but other organs such as the kidneys, lungs, and gastrointestinal tract can also play a role.

Biotransformation can occur in two phases: phase I reactions involve functionalization of the parent compound through oxidation, reduction, or hydrolysis, while phase II reactions involve conjugation of the metabolite with endogenous molecules such as glucuronic acid, sulfate, or acetate to increase its water solubility and facilitate excretion.

Mixed Function Oxygenases (MFOs) are a type of enzyme that catalyze the addition of one atom each from molecular oxygen (O2) to a substrate, while reducing the other oxygen atom to water. These enzymes play a crucial role in the metabolism of various endogenous and exogenous compounds, including drugs, carcinogens, and environmental pollutants.

MFOs are primarily located in the endoplasmic reticulum of cells and consist of two subunits: a flavoprotein component that contains FAD or FMN as a cofactor, and an iron-containing heme protein. The most well-known example of MFO is cytochrome P450, which is involved in the oxidation of xenobiotics and endogenous compounds such as steroids, fatty acids, and vitamins.

MFOs can catalyze a variety of reactions, including hydroxylation, epoxidation, dealkylation, and deamination, among others. These reactions often lead to the activation or detoxification of xenobiotics, making MFOs an important component of the body's defense system against foreign substances. However, in some cases, these reactions can also produce reactive intermediates that may cause toxicity or contribute to the development of diseases such as cancer.

Acetamides are organic compounds that contain an acetamide functional group, which is a combination of an acetyl group (-COCH3) and an amide functional group (-CONH2). The general structure of an acetamide is R-CO-NH-CH3, where R represents the rest of the molecule.

Acetamides are found in various medications, including some pain relievers, muscle relaxants, and anticonvulsants. They can also be found in certain industrial chemicals and are used as intermediates in the synthesis of other organic compounds.

It is important to note that exposure to high levels of acetamides can be harmful and may cause symptoms such as headache, dizziness, nausea, and vomiting. Chronic exposure has been linked to more serious health effects, including liver and kidney damage. Therefore, handling and use of acetamides should be done with appropriate safety precautions.

Immunohistochemistry (IHC) is a technique used in pathology and laboratory medicine to identify specific proteins or antigens in tissue sections. It combines the principles of immunology and histology to detect the presence and location of these target molecules within cells and tissues. This technique utilizes antibodies that are specific to the protein or antigen of interest, which are then tagged with a detection system such as a chromogen or fluorophore. The stained tissue sections can be examined under a microscope, allowing for the visualization and analysis of the distribution and expression patterns of the target molecule in the context of the tissue architecture. Immunohistochemistry is widely used in diagnostic pathology to help identify various diseases, including cancer, infectious diseases, and immune-mediated disorders.

The Cytochrome P-450 (CYP450) enzyme system is a group of enzymes found primarily in the liver, but also in other organs such as the intestines, lungs, and skin. These enzymes play a crucial role in the metabolism and biotransformation of various substances, including drugs, environmental toxins, and endogenous compounds like hormones and fatty acids.

The name "Cytochrome P-450" refers to the unique property of these enzymes to bind to carbon monoxide (CO) and form a complex that absorbs light at a wavelength of 450 nm, which can be detected spectrophotometrically.

The CYP450 enzyme system is involved in Phase I metabolism of xenobiotics, where it catalyzes oxidation reactions such as hydroxylation, dealkylation, and epoxidation. These reactions introduce functional groups into the substrate molecule, which can then undergo further modifications by other enzymes during Phase II metabolism.

There are several families and subfamilies of CYP450 enzymes, each with distinct substrate specificities and functions. Some of the most important CYP450 enzymes include:

1. CYP3A4: This is the most abundant CYP450 enzyme in the human liver and is involved in the metabolism of approximately 50% of all drugs. It also metabolizes various endogenous compounds like steroids, bile acids, and vitamin D.
2. CYP2D6: This enzyme is responsible for the metabolism of many psychotropic drugs, including antidepressants, antipsychotics, and beta-blockers. It also metabolizes some endogenous compounds like dopamine and serotonin.
3. CYP2C9: This enzyme plays a significant role in the metabolism of warfarin, phenytoin, and nonsteroidal anti-inflammatory drugs (NSAIDs).
4. CYP2C19: This enzyme is involved in the metabolism of proton pump inhibitors, antidepressants, and clopidogrel.
5. CYP2E1: This enzyme metabolizes various xenobiotics like alcohol, acetaminophen, and carbon tetrachloride, as well as some endogenous compounds like fatty acids and prostaglandins.

Genetic polymorphisms in CYP450 enzymes can significantly affect drug metabolism and response, leading to interindividual variability in drug efficacy and toxicity. Understanding the role of CYP450 enzymes in drug metabolism is crucial for optimizing pharmacotherapy and minimizing adverse effects.

Olfactory nerve injuries refer to damages or trauma inflicted on the olfactory nerve, which is the first cranial nerve (CN I) responsible for the sense of smell. The olfactory nerve has sensory receptors in the nasal cavity that detect and transmit smell signals to the brain.

Olfactory nerve injuries can occur due to various reasons, such as head trauma, viral infections, exposure to toxic chemicals, or neurodegenerative diseases like Parkinson's and Alzheimer's. The injury may result in a reduced or complete loss of the sense of smell (anosmia) or distorted smells (parosmia).

The diagnosis of olfactory nerve injuries typically involves a thorough clinical evaluation, including a detailed medical history, physical examination, and specific tests like those assessing the ability to identify and discriminate between various odors. Treatment options depend on the underlying cause and may include medications, surgery, or rehabilitation strategies aimed at improving sensory function.

Autoradiography is a medical imaging technique used to visualize and localize the distribution of radioactively labeled compounds within tissues or organisms. In this process, the subject is first exposed to a radioactive tracer that binds to specific molecules or structures of interest. The tissue is then placed in close contact with a radiation-sensitive film or detector, such as X-ray film or an imaging plate.

As the radioactive atoms decay, they emit particles (such as beta particles) that interact with the film or detector, causing chemical changes and leaving behind a visible image of the distribution of the labeled compound. The resulting autoradiogram provides information about the location, quantity, and sometimes even the identity of the molecules or structures that have taken up the radioactive tracer.

Autoradiography has been widely used in various fields of biology and medical research, including pharmacology, neuroscience, genetics, and cell biology, to study processes such as protein-DNA interactions, gene expression, drug metabolism, and neuronal connectivity. However, due to the use of radioactive materials and potential hazards associated with them, this technique has been gradually replaced by non-radioactive alternatives like fluorescence in situ hybridization (FISH) or immunofluorescence techniques.

C57BL/6 (C57 Black 6) is an inbred strain of laboratory mouse that is widely used in biomedical research. The term "inbred" refers to a strain of animals where matings have been carried out between siblings or other closely related individuals for many generations, resulting in a population that is highly homozygous at most genetic loci.

The C57BL/6 strain was established in 1920 by crossing a female mouse from the dilute brown (DBA) strain with a male mouse from the black strain. The resulting offspring were then interbred for many generations to create the inbred C57BL/6 strain.

C57BL/6 mice are known for their robust health, longevity, and ease of handling, making them a popular choice for researchers. They have been used in a wide range of biomedical research areas, including studies of cancer, immunology, neuroscience, cardiovascular disease, and metabolism.

One of the most notable features of the C57BL/6 strain is its sensitivity to certain genetic modifications, such as the introduction of mutations that lead to obesity or impaired glucose tolerance. This has made it a valuable tool for studying the genetic basis of complex diseases and traits.

Overall, the C57BL/6 inbred mouse strain is an important model organism in biomedical research, providing a valuable resource for understanding the genetic and molecular mechanisms underlying human health and disease.

Pyrazoles are heterocyclic aromatic organic compounds that contain a six-membered ring with two nitrogen atoms at positions 1 and 2. The chemical structure of pyrazoles consists of a pair of nitrogen atoms adjacent to each other in the ring, which makes them unique from other azole heterocycles such as imidazoles or triazoles.

Pyrazoles have significant biological activities and are found in various pharmaceuticals, agrochemicals, and natural products. Some pyrazole derivatives exhibit anti-inflammatory, analgesic, antipyretic, antimicrobial, antiviral, antifungal, and anticancer properties.

In the medical field, pyrazoles are used in various drugs to treat different conditions. For example, celecoxib (Celebrex) is a selective COX-2 inhibitor used for pain relief and inflammation reduction in arthritis patients. It contains a pyrazole ring as its core structure. Similarly, febuxostat (Uloric) is a medication used to treat gout, which also has a pyrazole moiety.

Overall, pyrazoles are essential compounds with significant medical applications and potential for further development in drug discovery and design.

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

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

Tissue distribution, in the context of pharmacology and toxicology, refers to the way that a drug or xenobiotic (a chemical substance found within an organism that is not naturally produced by or expected to be present within that organism) is distributed throughout the body's tissues after administration. It describes how much of the drug or xenobiotic can be found in various tissues and organs, and is influenced by factors such as blood flow, lipid solubility, protein binding, and the permeability of cell membranes. Understanding tissue distribution is important for predicting the potential effects of a drug or toxin on different parts of the body, and for designing drugs with improved safety and efficacy profiles.

Neuroglia, also known as glial cells or simply glia, are non-neuronal cells that provide support and protection for neurons in the nervous system. They maintain homeostasis, form myelin sheaths around nerve fibers, and provide structural support. They also play a role in the immune response of the central nervous system. Some types of neuroglia include astrocytes, oligodendrocytes, microglia, and ependymal cells.

Neurons, also known as nerve cells or neurocytes, are specialized cells that constitute the basic unit of the nervous system. They are responsible for receiving, processing, and transmitting information and signals within the body. Neurons have three main parts: the dendrites, the cell body (soma), and the axon. The dendrites receive signals from other neurons or sensory receptors, while the axon transmits these signals to other neurons, muscles, or glands. The junction between two neurons is called a synapse, where neurotransmitters are released to transmit the signal across the gap (synaptic cleft) to the next neuron. Neurons vary in size, shape, and structure depending on their function and location within the nervous system.

"Wistar rats" are a strain of albino rats that are widely used in laboratory research. They were developed at the Wistar Institute in Philadelphia, USA, and were first introduced in 1906. Wistar rats are outbred, which means that they are genetically diverse and do not have a fixed set of genetic characteristics like inbred strains.

Wistar rats are commonly used as animal models in biomedical research because of their size, ease of handling, and relatively low cost. They are used in a wide range of research areas, including toxicology, pharmacology, nutrition, cancer, cardiovascular disease, and behavioral studies. Wistar rats are also used in safety testing of drugs, medical devices, and other products.

Wistar rats are typically larger than many other rat strains, with males weighing between 500-700 grams and females weighing between 250-350 grams. They have a lifespan of approximately 2-3 years. Wistar rats are also known for their docile and friendly nature, making them easy to handle and work with in the laboratory setting.

Sprague-Dawley rats are a strain of albino laboratory rats that are widely used in scientific research. They were first developed by researchers H.H. Sprague and R.C. Dawley in the early 20th century, and have since become one of the most commonly used rat strains in biomedical research due to their relatively large size, ease of handling, and consistent genetic background.

Sprague-Dawley rats are outbred, which means that they are genetically diverse and do not suffer from the same limitations as inbred strains, which can have reduced fertility and increased susceptibility to certain diseases. They are also characterized by their docile nature and low levels of aggression, making them easier to handle and study than some other rat strains.

These rats are used in a wide variety of research areas, including toxicology, pharmacology, nutrition, cancer, and behavioral studies. Because they are genetically diverse, Sprague-Dawley rats can be used to model a range of human diseases and conditions, making them an important tool in the development of new drugs and therapies.

Esthesioneuroblastoma, also known as olfactory neuroblastoma, is a rare type of malignant tumor that develops in the upper part of the nasal cavity, near the area responsible for the sense of smell (olfaction). It arises from the olfactory nerve cells and typically affects adults between 20 to 50 years old, although it can occur at any age.

Esthesioneuroblastomas are characterized by their aggressive growth and potential to spread to other parts of the head and neck, as well as distant organs such as the lungs, bones, and bone marrow. Symptoms may include nasal congestion, nosebleeds, loss of smell, facial pain or numbness, bulging eyes, and visual disturbances.

Diagnosis is usually made through a combination of clinical examination, imaging studies (such as MRI or CT scans), and biopsy. Treatment typically involves surgical resection of the tumor, followed by radiation therapy and/or chemotherapy to reduce the risk of recurrence. Regular follow-up care is essential due to the possibility of late relapse.

Overall, prognosis varies depending on factors such as the stage of the disease at diagnosis, the patient's age, and the effectiveness of treatment. While some individuals may experience long-term survival or even cure, others may face more aggressive tumor behavior and a higher risk of recurrence.

The Vomeronasal Organ (VNO) is a chemosensory organ found in many animals, including humans, that is involved in the detection of pheromones and other chemical signals. It's located in the nasal cavity, specifically on the septum, which separates the two nostrils.

In humans, the existence and functionality of the VNO have been a subject of debate among researchers. While it is present in human embryos and some studies suggest that it may play a role in the detection of certain chemicals, its significance in human behavior and physiology is not well understood. In many other animals, however, the VNO plays a crucial role in social behaviors such as mating, aggression, and hierarchy establishment.

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

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

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

Arthropod antennae are the primary sensory organs found in arthropods, which include insects, crustaceans, arachnids, and myriapods. These paired appendages are usually located on the head or nearest segment to the head and are responsible for detecting various stimuli from the environment such as touch, taste, smell, temperature, humidity, vibration, and air motion.

The structure of arthropod antennae varies among different groups but generally consists of one or more segments called flagellum or funicle that may be further divided into subsegments called annuli. The number and arrangement of these segments are often used to classify and identify specific taxa.

Insect antennae, for example, typically have a distinct shape and can be thread-like, feathery, or clubbed depending on the species. They contain various sensory receptors such as olfactory neurons that detect odor molecules, mechanoreceptors that respond to touch or movement, and thermoreceptors that sense temperature changes.

Overall, arthropod antennae play a crucial role in enabling these organisms to navigate their environment, find food, avoid predators, and communicate with conspecifics.

Enzyme induction is a process by which the activity or expression of an enzyme is increased in response to some stimulus, such as a drug, hormone, or other environmental factor. This can occur through several mechanisms, including increasing the transcription of the enzyme's gene, stabilizing the mRNA that encodes the enzyme, or increasing the translation of the mRNA into protein.

In some cases, enzyme induction can be a beneficial process, such as when it helps the body to metabolize and clear drugs more quickly. However, in other cases, enzyme induction can have negative consequences, such as when it leads to the increased metabolism of important endogenous compounds or the activation of harmful procarcinogens.

Enzyme induction is an important concept in pharmacology and toxicology, as it can affect the efficacy and safety of drugs and other xenobiotics. It is also relevant to the study of drug interactions, as the induction of one enzyme by a drug can lead to altered metabolism and effects of another drug that is metabolized by the same enzyme.

Necrosis is the premature death of cells or tissues due to damage or injury, such as from infection, trauma, infarction (lack of blood supply), or toxic substances. It's a pathological process that results in the uncontrolled and passive degradation of cellular components, ultimately leading to the release of intracellular contents into the extracellular space. This can cause local inflammation and may lead to further tissue damage if not treated promptly.

There are different types of necrosis, including coagulative, liquefactive, caseous, fat, fibrinoid, and gangrenous necrosis, each with distinct histological features depending on the underlying cause and the affected tissues or organs.

Glands of the olfactory mucosa secrete a mostly serous fluid. The olfactory mucosa consists of the olfactory epithelium and the ... The olfactory mucosa is the neuroepithelialial mucosa lining the roof and upper parts of the septum and lateral wall of the ... The olfactory mucosa is thicker and lighter in colour (yellowish-brown) in comparison to the (pinkish) respiratory mucosa ... The part of the nasal cavity that is lined with olfactory mucosa is known as the olfactory region (pars olfactoria tunicae ...
Olfactory adult stem cells have been successfully harvested from the human olfactory mucosa cells, which are found in the ... June 2005). "Multipotent stem cells from adult olfactory mucosa". Developmental Dynamics. 233 (2): 496-515. doi:10.1002/dvdy. ... Olfactory stem cells hold the potential for therapeutic applications and, in contrast to neural stem cells, can be harvested ...
Behind the nose are the olfactory mucosa and the sinuses. Behind the nasal cavity, air next passes through the pharynx, shared ... The olfactory chamber is lined by olfactory epithelium on its upper surface and possesses a number of turbinates to increase ... These sacs contain a small amount of olfactory epithelium, which, in the case of caecilians, also lines a number of ... Since they generally have a poor sense of smell, the olfactory chamber is small, although it does contain three turbinates, ...
Rodriguez I, Greer CA, Mok MY, Mombaerts P (Sep 2000). "A putative pheromone receptor gene expressed in human olfactory mucosa ... Vomeronasal receptors are a class of olfactory receptors that putatively function as receptors for pheromones. Pheromones have ... a receptor from goldfish olfactory epithelium has been reported to bind basic amino acids, which are odorants for fish. V1 ... but an apparently functional receptor has been identified that is expressed in the human olfactory system. The V2 receptors are ...
The protein encoded by this gene is similar to pheromone receptors and is primarily localized to the olfactory mucosa. An ... "A putative pheromone receptor gene expressed in human olfactory mucosa". Nature Genetics. 26 (1): 18-9. doi:10.1038/79124. PMID ...
There also have been pheromone receptor genes found in olfactory mucosa. There have been no experiments that compare people ... In humans and other animals, TAARs in the olfactory epithelium function as olfactory receptors that detect volatile amine ... The associated olfactory bulb is present in the fetus, but regresses and vanishes in the adult brain. There have been some ... Olfactory processing of chemical signals like pheromones exists in all animal phyla and is thus the oldest of the senses.[ ...
"Transplantation of olfactory mucosa following spinal cord injury promotes recovery in rats". NeuroReport. 19 (13): 1249-52. doi ... Transplantation of tissues such as olfactory ensheathing cells from the olfactory bulbs has been shown to produce beneficial ... The OECs were taken from the patient's olfactory bulbs in his brain and then grown in the lab, these cells were then injected ... Trials have also begun to show success when olfactory ensheathing cells are transplanted into humans with severed spinal cords ...
"Novel genes for potential ligand-binding proteins in subregions of the olfactory mucosa". The EMBO Journal. 10 (10): 2813-9. ... BPIFB3 was first directly identified in a screen of rat olfactory epithelium as RYA3 and was recognized to be a member of the ... BPIFB3/RYA3 is highly expressed in olfactory epithelium and the tongue, within the cytoplasm of cells, and is thought to be ... characterization of the RY gene cluster in 20q11.21 encoding olfactory transporters/antimicrobial-like peptides". Genomics. 82 ...
"Novel genes for potential ligand-binding proteins in subregions of the olfactory mucosa". The EMBO Journal. 10 (10): 2813-9. ... Vomeromodulin is highly expressed in nasal mucosa, particularly within a structure known as the Vomeronasal organ. The ... Those odorant receptors, in turn, are associated with nasal epithelial cells integrated with olfactory neurons that project ... and esophageal mucosa. Yet, definitive evidence for human BPIFB9 protein has never been produced and is unlikely to happen. The ...
Tubuloalveolar serous secreting glands lying in the lamina propria of the olfactory mucosa. These glands deliver a ... The olfactory epithelium contains olfactory sensory neurons, whose axons innervate the olfactory bulb. In order for olfactory ... The olfactory epithelium is the part of the olfactory system directly responsible for detecting odors. Olfactory epithelium ... The olfactory placode forms as two thickenings of non-neural region of embryonic ectoderm. In mice, the olfactory placode ...
Gu J, Su T, Chen Y, Zhang QY, Ding X (Jun 2000). "Expression of biotransformation enzymes in human fetal olfactory mucosa: ...
The horse's olfactory receptors are located in the mucosa of the upper nasal cavity. Due to the length of the nasal cavity, ...
... expressed in olfactory mucosa". Biochemical and Biophysical Research Communications. 323 (2): 429-436. doi:10.1016/j.bbrc. ...
"Diagnosis of Human Prion Disease Using Real-Time Quaking-Induced Conversion Testing of Olfactory Mucosa and Cerebrospinal Fluid ... In 2014, a human study showed a nasal brushing method that can accurately detect PrP in the olfactory epithelial cells of ...
2000). "The expression of alpha-, beta-, and gamma-synucleins in olfactory mucosa from patients with and without ... It is also detected in the brain, ovarian tumors, and in the olfactory epithelium. Gamma-synuclein is the least conserved of ...
N. fowleri invades the central nervous system via the nose, specifically through the olfactory mucosa of the nasal tissues. ... such as damage to the olfactory nerve through lysis of nerve cells and demyelination. Specifically, the olfactory nerve and ... There, it migrates to the olfactory bulbs and subsequently other regions of the brain, where it feeds on the nerve tissue. The ... It then migrates through the cribriform plate and into the olfactory bulbs of the forebrain, where it multiplies itself greatly ...
Another study investigated morphological changes in olfactory mucosa of Tilapia mariae when exposed to low levels of the copper ... Olfactory toxicity due to metals cause a general depression of the olfactory system leading to decreased sense of smell, loss ... Olfactory information is received by sensory neurons, like the olfactory nerve, that are in a covered cavity separated from the ... Olfactory toxicity in fishes. Aquatic Toxicology 96 2-26. Tierney KB, Singh CR, Ross PS, Kennedy CJ. 2007. Relating olfactory ...
The sense of smell is generated by receptor cells in the epithelium of the olfactory mucosa in the nasal cavity. This ... This nerve transmits to the neural circuitry of the olfactory bulb from where information is passed to the olfactory cortex. ... The ventral striatum consists of the nucleus accumbens and the olfactory tubercle whereas the dorsal striatum consists of the ... information passes via the olfactory nerve which goes into the skull through a relatively permeable part. ...
548 The specialized olfactory receptor neurons of the olfactory nerve are located in the olfactory mucosa of the upper parts of ... amoeba enter through the olfactory mucosa of the nasal tissues and follow the olfactory nerve fibers into the olfactory bulbs ... The olfactory nerve is sensory in nature and originates on the olfactory mucosa in the upper part of the nasal cavity. From the ... the olfactory information is transmitted into the brain via the olfactory tract. The fascicles of the olfactory nerve are not ...
After nasal administration of microcystin-LR, the epithelium of nasal mucosa of both the olfactory and respiratory zones were ...
In the olfactory mucosa it is believed to act similarly to other BPIFB proteins in the innate immune response to bacterial ... In a variety of mammals, BPIFB4 is generally expressed in very high levels in the olfactory epithelium (nasal mucosa), high ... BPIFB4 protein is normally expressed in olfactory epithelium, mononuclear cells and macrophage-like cells as well as a variety ... characterization of the RY gene cluster in 20q11.21 encoding olfactory transporters/antimicrobial-like peptides". Genomics. 82 ...
... to the olfactory mucosa. However, lidocaine treatment might lead to unspecific effects and not represent a direct interference ... When woodmice are removed from their home area and deprived of visual and olfactory cues, they orient towards their homes until ...
The resulting BPIFA1 is a secreted protein, expressed at very high levels in mucosa of the airways (olfactory and respiratory ... BPIFA1 has multiple functions but perhaps its most prominent ones are related to BPIFA1's localization in nasal, olfactory, ...
"Targeted Disruption of the Olfactory Mucosa-Specific Cyp2g1 Gene: Impact on Acetaminophen Toxicity in the Lateral Nasal Gland, ... Sustentacular cells of the olfactory epithelium (also called supporting cells or Sertoli cells) have been shown to be involved ... Suzuki, Yuko; Takeda, Masako; Farbman, Albert I. (1996). "Supporting cells as phagocytes in the olfactory epithelium after ... Implications in Olfactory Perireceptor Events: Odorant-Binding Proteins and Metabolizing Enzymes". The Anatomical Record. 296 ( ...
Moran, D. T.; Rowley, J. C.; Jafek, B. W.; Lovell, M. A. (1982-10-01). "The fine structure of the olfactory mucosa in man". ... the olfactory receptor cells in the olfactory epithelium, mitral cells, and olfactory pyramidal neurons. At the level of the ... The first stop in the olfactory system is the olfactory epithelium, or tissue resting on the roof of the nasal cavity which ... Each olfactory cell has a single type of receptor, but that receptor can be "broadly tuned" and odor molecules further interact ...
"Functional Morphology of the Olfactory Mucosa and Olfactory Bulb in Fossorial Rodents: The East African Root Rat ( Tachyoryctes ... Some researchers found that their olfactory systems have increased surface area and are highly complex, an evolved trait that ...
... s have an acute sense of smell, due in part to their well-developed olfactory bulb and a large surface of olfactory mucosa, ... Sommerville, B. A. (1998). "Olfactory Awareness". Applied Animal Behaviour Science. 57 (3-4): 269-286. doi:10.1016/S0168-1591( ...
Apart from the Bowman's capsule, other anatomical structures named after him include: Bowman's glands - in the olfactory mucosa ...
... , also known as Bowman's glands, are a type of nasal gland situated in the part of the olfactory mucosa beneath ... The olfactory glands are tubuloalveolar glands surrounded by olfactory receptors and sustentacular cells in the olfactory ... An olfactory gland consists of an acinus in the lamina propria and a secretory duct going out through the olfactory epithelium ... Electron microscopy studies show that olfactory glands contain cells with large secretory vesicles. Olfactory glands secrete ...
... made up of the axons from approximately ten million olfactory receptor neurons in the olfactory mucosa, a region of the nasal ... Additionally, top down input to the olfactory bulb differentially affects olfactory outputs. The olfactory bulb sends olfactory ... Therefore, the olfactory bulb plays this role for the olfactory system. In vertebrates, the accessory olfactory bulb (AOB), ... As a neural circuit, the olfactory bulb has one source of sensory input (axons from olfactory receptor neurons of the olfactory ...
Glands of the olfactory mucosa secrete a mostly serous fluid. The olfactory mucosa consists of the olfactory epithelium and the ... The olfactory mucosa is the neuroepithelialial mucosa lining the roof and upper parts of the septum and lateral wall of the ... The olfactory mucosa is thicker and lighter in colour (yellowish-brown) in comparison to the (pinkish) respiratory mucosa ... The part of the nasal cavity that is lined with olfactory mucosa is known as the olfactory region (pars olfactoria tunicae ...
A unique type of MSC termed olfactory mucosa mesenchymal stem cell (OM-MSC) confers neuroprotection by promoting the secretion ... Hypoxia-preconditioned olfactory mucosa mesenchymal stem cells abolish cerebral ischemia/reperfusion-induced pyroptosis and ... Hypoxia-preconditioned olfactory mucosa mesenchymal stem cells abolish cerebral ischemia/reperfusion-induced pyroptosis and ... A unique type of MSC termed olfactory mucosa mesenchymal stem cell (OM-MSC) confers neuroprotection by promoting the secretion ...
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The olfactory mucosa (OM) is a distinctive way to obtain regenerative. The olfactory mucosa (OM) is a distinctive way to obtain ... This review targets another paradigm with an identical purpose with specific talents; the olfactory mucosa (OM) tissues ... function within the olfactory neurocircuitry. Furthermore we discuss different approaches to lifestyle of OM-derived cells and ... Neural tissue without genomic reprogramming could be captured via olfactory biopsy. OM tissue give and neuronal cells that ...
Dive into the research topics of Role of CYP2A5 and 2G1 in acetaminophen metabolism and toxicity in the olfactory mucosa of ... Role of CYP2A5 and 2G1 in acetaminophen metabolism and toxicity in the olfactory mucosa of the Cyp1A2(-/-)mouse. ...
... but elimination of main olfactory system function by ZnSO4 treatment of the olfactory mucosa did abolish such preferences. Thus ... These processes are mediated by the main olfactory system but not the vomeronasal accessory-olfactory system. ... Individual recognition of female hamsters by males: role of chemical cues and of the olfactory and vomeronasal systems Physiol ... olfactory cues are sufficient for individual discrimination of novel females by sexually satiated male hamsters, and such ...
... of the olfactory mucosa; see the image below), and nasopharyngeal carcinoma. ... Eleven pairs of cranial nerves and the olfactory nerves (CN I) pass through the inner table of the skull via 7 pairs of bony ... Esthesioneuroblastoma, also termed olfactory neuroblastoma, is a very rare tumor. Nasopharyngeal carcinoma is the most common ... in the olfactory groove. [15] Meningiomas of the floor of the middle fossa are uncommon and tend to grow quite large before ...
Surface of the olfactory mucosa (cm2). 60 to 200. 3 to 10 ... Comparison of Olfactory Performance in Dogs and Humans. (from ... The dog has 70 - 200 million olfactory receptors, compared with a humans 5 to 20 million receptors (Vadurel & Gogny, 1997). ... Olfactory acuity is at a maximum when the dog is hungry and falls when the dog is satiated. ...
... olfactory mucosa was mostly spared. The SARS-CoV-2 receptor ACE2 was extensively detected by IHC within turbinate epithelium, ... olfactory marker protein; RT-PCR; severe acute respiratory syndrome coronavirus 2 ...
Ni and V were present in a gradient from olfactory mucosa , olfactory bulb , frontal cortex. Exposed dogs had (a) nuclear ... Nasal respiratory and olfactory epithelium were found to be early pollutant targets. Olfactory bulb and hippocampal AP sites ... Respiratory tract inflammation and deteriorating olfactory and respiratory barriers may play a role in the observed ... and disruption of the nasal respiratory and olfactory barriers are likely in these populations. DNA damage is crucial in aging ...
... olfactory mucosa swabbing and/or skin biopsy.. *The Frequency of Visits: Study participants who are presymptomatic or ...
This epithelium lines most of the sinonasal tract with the exception of the olfactory mucosa. ... Nasal mucosa. The nasal vestibule, constituting the first 1-2 cm of the nasal cavity, is lined with keratinized, stratified ... In general, the nose is innervated by the olfactory nerve, branches of the ophthalmic and maxillary divisions of the trigeminal ... Apply topical decongestant to evaluate the response of the turbinate mucosa. This may assist in delineating mucosal versus bony ...
... and exhaust after-treatment systems with an examination of their effects in a human-derived cell model of the olfactory mucosa. ... Exposure to ultrafine particles from traffic alters the expression of many genes in human olfactory mucosa cells, a new study ... olfactory signalling and olfactory mucosa integrity. However, renewable diesel caused less adverse effects than fossil diesel. ... The human olfactory mucosa is a tissue directly exposed to the environment and in direct contact with the brain. ...
... indicating that NPY is required for reading olfactory circuits during behavioural expression rather than writing olfactory ... Together, these findings show that food-odour-responsive neurons comprise an olfactory subcircuit that listens to hunger state ... Here we identify a neuronal mechanism by which hunger selectively promotes attraction to food odours over other olfactory cues ... Neuropeptide Y enhances olfactory mucosa responses to odorant in hungry rats. PLoS ONE 7, e45266 (2012). ...
Different odorants stimulate different places in the olfactory mucosa. Correct Answer. A. Different odorants attach to ...
Odor-evoked responses are conducted from olfactory receptor neurons at the nasal mucosa toward the olfactory bulb. Second-order ... 1996) Olfactory neuronal responses in the primate orbitofrontal cortex: analysis in an olfactory discrimination task. J ... Our principal objective was to define regions responsive to olfactory stimulation and odor valence. Olfactory perception is ... 1991) Olfactory evoked potentials in humans. in Smell and taste in health and disease, eds Getchell TV, Doty RL, Bartoshuk LM, ...
Again, RT-QuIC has high diagnostic accuracy for cerebrospinal fluid, olfactory mucosa, and skin samples of sporadic Creutzfeldt ...
Breathlessness, Inspiratory neural drive, Nasal mucosa, Olfactory nerve, Trigeminal nerve, TRPM8 channels. in Respiratory ... Nasal mucosa; Olfactory nerve; Trigeminal nerve; TRPM8 channels}}, language = {{eng}}, publisher = {{Elsevier}}, series = {{ ... Impact of trigeminal and/or olfactory nerve stimulation on measures of inspiratory neural drive : Implications for ... Respiratory Physiology and Neurobiology}}, title = {{Impact of trigeminal and/or olfactory nerve stimulation on measures of ...
A spatially-resolved, single-cell analysis of human olfactory cleft mucosa highlights the transcriptional dysregulation in ... A spatially-resolved, single-cell analysis of human olfactory cleft mucosa highlights the transcriptional dysregulation in ...
... olfactory loss, and response to viral infection. Ongoing work explores how epithelial cells of the sinuses and olfactory mucosa ... as well as inflammation on the olfactory epithelium. Diverse techniques in molecular biology, immunology, and physiology are ...
... and could penetrate through the olfactory mucosa and then the receptors and olfactory nerves as entry points (1, 8, 9). ... Damage to the olfactory nerve, thalamus and brain stem was demonstrated in a mouse model with intranasal injection of the virus ...
Olfactory Mucosa, Paired Box Transcription Factors, Phenotype, Pregnancy, Repressor Proteins, Retina",. author = "Collinson, {J ... Collinson, J. M., Quinn, J. C., Hill, R. E., & West, J. D. (2003). The roles of Pax6 in the cornea, retina, and olfactory ... The roles of Pax6 in the cornea, retina, and olfactory epithelium of the developing mouse embryo. In: Developmental Biology. ... Collinson, JM, Quinn, JC, Hill, RE & West, JD 2003, The roles of Pax6 in the cornea, retina, and olfactory epithelium of the ...
", "olfactory", "manducatory" and even, "paludal mucosae" fall from the lips of storytellers of every condition. In French this ...
Background: The olfactory mucosa (OM) is crucial for odorant perception in the main olfactory system. The terminal ... Lectin histochemistry of the olfactory mucosa of Korean native cattle, Bos taurus coreanae Jang S, Kim B, Lee J, Kang S, Kim JS ... carbohydrates of glycoconjugates influence chemoreception in the olfactory epithelium (OE). Objectives: The histological ...
It also enters the brain predominantly through the olfactory mucosa (the first feature is the development of anosmia) and could ... gastric mucosa, and cancer. Recently, experimental and clinical pieces of evidence suggested that Ang (1-7) or Mas analogs ...
Biometal Dyshomeostasis in Olfactory Mucosa of Alzheimers Disease Patients.. Department of Genetic Toxicology and Epigenetics ... Emissions from modern engines induce distinct effects in human olfactory mucosa cells, depending on fuel and aftertreatment ...
Youve got different receptors and different volatile substances, and various parts of the olfactory mucosa signal various ... Youve got the olfactory epithelium sitting right there rather than the receptors buried in the skin. But still, I mean, ... but in terms of what theyre doing with genes and the molecular biology of the olfactory system, its astounding. ...
Metabolic Basis of Tissue-Selective Toxicity in Olfactory Mucosa of Rats and Mice Xiaoliang Zhuo, Jun Gu, Qing-Yu Zhang, David ...
  • CB1 receptors and obesity Type 1 cannabinoid receptors (CB1 receptors) are present in the sustentacular cells of the olfactory mucosa, in the periglomerular cells of the olfactory bulb, and in the anterior olfactory nucleus and olfactory cortices. (
  • Olfactory bulb and hippocampal AP sites were significantly higher in exposed than in control age matched animals. (
  • Odor-evoked responses are conducted from olfactory receptor neurons at the nasal mucosa toward the olfactory bulb. (
  • We assessed olfactory bulb (OB) volume with magnetic resonance imaging in 67 healthy participants with a body mass index (BMI) from 18.9 to 45.4 kg/m 2 (mean = 28.58 ± 6.64). (
  • In the nostrils there is the olfactory mucosa which is responsible for receiving the "odorific message" (the smell or aroma), which will be transported by the olfactory nerve fibers to the olfactory bulb. (
  • Objectives: This study demonstrates histopathologic and immunocytochemical changes in the olfactory bulb of a patient with post-traumatic olfactory dysfunction. (
  • Results: Pathological analysis of the olfactory bulb revealed a marked reduction in the number of nerve processes with few intact olfactory glomeruli compared with an age-matched control. (
  • Specific immunohistochemical staining for the olfactory neuron-specific protein OMP, however, demonstrated the presence of intact axonal projections between the olfactory mucosa and the bulb. (
  • Conclusions: These results support the hypothesis that post-traumatic anosmia involves, at least in part, damage to peripheral olfactory nerve fibers with histological changes in the olfactory bulb. (
  • mAb 5B4 intensely stains a variable proportion of olfactory axons in the mucosa as well as in the olfactory bulb. (
  • These neurons are arranged with dendrites positioned in the inferior space of the nasal cavity and an axon that projects through the cribriform plate to the olfactory nerve, and subsequently the olfactory bulb. (
  • The axons of these OSNs that express the same olfactory receptors come together to form glomeruli in the olfactory bulb. (
  • tein, and neuronal cell adhesion molecule mRNA were also increased in olfactory bulb. (
  • right nostril occluded for a 2-day exposure, Mn accumulated only in the left olfactory bulb. (
  • Methimazole toxicity in rodents: covalent binding in the olfactory mucosa and detection of glial fibrillary acidic protein in the olfactory bulb. (
  • It is feasible to argue the hypothesis of the involvement of the foetus' olfactory bulb as one of the indelible pathophysiological manifestations to the clinical diagnosis of COVID-19 with neurosensory olfactory deficit in foetuses and newborns affected by intrauterine infection. (
  • The olfactory mucosa consists of the olfactory epithelium and the underlying lamina propria, connective tissue containing fibroblasts, blood vessels, Bowman's glands and bundles of fine axons from the olfactory neurons. (
  • The mucus protects the olfactory epithelium and allows odors to dissolve so that they can be detected by olfactory receptor neurons. (
  • Nasal respiratory and olfactory epithelium were found to be early pollutant targets. (
  • The Lane laboratory is focused on understanding molecular mechanisms underlying chronic rhinosinusitis, particularly the pathogenesis of nasal polyps, as well as inflammation on the olfactory epithelium. (
  • In addition to the olfactory neurons, the epithelium is composed of supporting cells, Bowman glands and ducts unique to the olfactory epithelium, and basal cells that allow for the regeneration of the epithelium, including the olfactory sensory neurons. (
  • OSNs are located in the olfactory epithelium in the nose, where its cell bodies are distributed among all three of its stratified layers. (
  • The olfactory epithelium has a thin layer of mucus covering its surface. (
  • In this activation process, an odorant molecule will dissolve into the mucous membrane of the olfactory epithelium and subsequently bind to an olfactory receptor. (
  • The olfactory mucosa is the neuroepithelialial mucosa lining the roof and upper parts of the septum and lateral wall of the nasal cavity which contains bipolar neurons of the primary receptor neurons of the olfactory pathway, as well as supporting cells. (
  • The neurons' dendrites project towards the nasal cavity while their axons ascend through the cribriform plate as the olfactory nerves. (
  • and basal cells, the stem cells that continuously give rise to new olfactory receptor neurons and sustentacular cells. (
  • Together, these findings show that food-odour-responsive neurons comprise an olfactory subcircuit that listens to hunger state through thalamic NPY release, and more generally, provide mechanistic insights into how internal state regulates behaviour. (
  • The present paper reports on the localization by immunofluorescence of 5B4 antigen in cultured cortical neurons, developing spinal cord, and the mature olfactory system. (
  • As humans age, the number of olfactory neurons steadily decreases. (
  • Olfactory sensory neurons are transduction cells that total about six million in humans (Moran et al. (
  • Individual odors are characterized by patterns of activated neurons in an olfactory region. (
  • Eleven pairs of cranial nerves and the olfactory nerves (CN I) pass through the inner table of the skull via 7 pairs of bony foramina and the cribriform plate (CN I). The skull base also has multiple foramina that provide passage for vascular and other neural elements. (
  • and could penetrate through the olfactory mucosa and then the receptors and olfactory nerves as entry points ( 1 , 8 , 9 ). (
  • via the olfactory nerves causing primary amebic meningoencephalitis (PAM). (
  • It is a specialized pseudostratified neuroepithelium containing the primary olfactory receptors. (
  • To stimulate the olfactory receptors, airborne molecules must pass through the nasal cavity with relatively turbulent air currents and contact the receptors. (
  • The surface of these hair-like cilia is blanketed with olfactory receptors. (
  • These olfactory receptors are a type of G protein-coupled receptor, which means the receptors are inherently metabotropic. (
  • 2004). Olfactory receptors on different OSNs can detect new odors from background environmental odors. (
  • Activated olfactory receptors then activate intracellular G protein, guanine nucleotide-binding protein (GNAL), adenylate cyclase, and the production of cyclic adenosine monophosphate (cAMP). (
  • Olfactory receptors are the largest gene family. (
  • It is estimated that there are 1,000 different genes that code for olfactory receptors. (
  • That being said, there are many separate OSNs that express olfactory receptors, which bind to the same set of odors. (
  • Piriform cortex is the major recipient of bulbar afferents, but additional targets comprise olfactory tubercle, anterior olfactory nucleus, periamygdaloid cortex, and entorhinal area. (
  • Mitral cells innervate the following brain areas: the medial amygdala, anterior olfactory nucleus, entorhinal cortex, olfactory tubercle, and piriform cortex. (
  • Because distinct flavors depend on aromas to stimulate the olfactory chemoreceptors, smell and taste are physiologically interdependent. (
  • A study in 2008 in mice has shown that the level of CB1 expression in various brain regions, including the olfactory nucleus, is modulated by diet-induced obesity. (
  • Respiratory tract inflammation, production of mediators of inflammation capable of reaching the brain, systemic circulation of PM, and disruption of the nasal respiratory and olfactory barriers are likely in these populations. (
  • The human olfactory mucosa is a tissue directly exposed to the environment and in direct contact with the brain. (
  • The olfactory system has been found to mediate the effects of environmental pollutants on the brain, thus contributing to the pathogenesis of brain diseases. (
  • The findings back earlier studies suggesting that PAHs may disturb the inflammatory response and xenobiotic metabolism in human olfactory mucosa cells, and that ultrafine particles may mediate adverse effects to the brain via the olfactory pathway. (
  • They also show that brain regions mediating emotional processing are differentially activated by odor valence, providing evidence for a close anatomical coupling between olfactory and emotional processes. (
  • Nevertheless, one way in which SARS-CoV-2 might be accessing the brain, experts have said, is by passing through the olfactory mucosa, the lining of the nasal cavity, which borders the brain. (
  • CONCLUSIONS: We conclude that the olfactory neuronal pathway is efficient for translocating in the brain. (
  • The part of the nasal cavity that is lined with olfactory mucosa is known as the olfactory region (pars olfactoria tunicae mucosae nasi), while the rest of the nasal cavity that is lined by ordinary respiratory mucosa is known as the respiratory region. (
  • Parts of the nasal cavity lined by olfactory mucosa include: parts of the roof of the nasal cavity, the superior nasal concha and some upper parts of the middle nasal concha, parts of the nasal septum, and the sphenoethmoidal recess. (
  • The olfactory mucosa is thicker and lighter in colour (yellowish-brown) in comparison to the (pinkish) respiratory mucosa lining the rest of the nasal cavity. (
  • The enlarged nasal cavity resulting from turbinate resection was believed to increase nasal airflow and reduce the humidifying capabilities of the nasal mucosa, resulting in drying, crusting, and mucosal atrophy. (
  • In primary olfactory (piriform) cortex, spatially and temporally dissociable responses were identified along a rostrocaudal axis. (
  • Second-order projections transmit via the lateral olfactory tract and terminate in adjacent structures collectively labeled "primary olfactory cortex. (
  • Irreversible binding and toxicity of the herbicide dichlobenil (2,6-dichlorobenzonitrile) in the olfactory mucosa of mice. (
  • Bahrami F, Brittebo EB, Bergman A, Larsson C, Brandt I. Localization and comparative toxicity of methylsulfonyl-2,5- and 2,6-dichlorobenzene in the olfactory mucosa of mice. (
  • Exposure to ultrafine particles from traffic alters the expression of many genes in human olfactory mucosa cells, a new study shows. (
  • Exposure to ultrafine particles altered human olfactory mucosa cell function, and different fuels and engines caused different adverse effects. (
  • The study offers important insight into the adverse effects of ultrafine particles in a human-derived cell model of the olfactory mucosa, providing a basis for possible measures to mitigate and prevent toxicological hazards. (
  • Respiratory tract inflammation and deteriorating olfactory and respiratory barriers may play a role in the observed neuropathology. (
  • In neonates, this area is a dense neural sheet, but, in children and adults, the respiratory and olfactory tissues interdigitate. (
  • An olfactory sensory neuron (OSN) is a component within the olfactory system used to detect airborne chemicals that are inhaled, which gives rise to the sense of olfaction or smell. (
  • There are many cilia that project into this mucus layer from the olfactory sensory neuron's dendrites. (
  • The olfactory sensory neuron is equipped with a rapid negative feedback mechanism upon depolarization. (
  • This study aims to investigate if newborn children of women infected with COVID-19 during pregnancy have olfactory sensory changes. (
  • The few studies that have evaluated this alteration in the paediatric range have shown that children have less olfactory sensory loss than adults. (
  • The authors propose to evaluate the action of SARS-CoV-2 at the intrauterine level regarding the foetus' olfactory sensory impairment. (
  • This study aims to assess the olfactory sensory perception of newborns of women who previously tested positive for COVID-19 during pregnancy compared to newborns of women who did not test positive for COVID-19 during pregnancy. (
  • It also aims to develop and validate a behavioural evaluation scale of olfactory sensory-perceptual perception in newborns. (
  • The olfactory neuroepithelium is located at the upper area of each nasal chamber adjacent to the cribriform plate, superior nasal septum, and superior-lateral nasal wall. (
  • In the center of this region is the cribriform plate, through which the olfactory tracts pass. (
  • Here we identify a neuronal mechanism by which hunger selectively promotes attraction to food odours over other olfactory cues. (
  • The olfactory mucosa (OM) is a distinctive way to obtain regenerative neural tissue that's readily obtainable from living human subjects and therefore affords opportunities for the analysis of psychiatric illnesses. (
  • Neural tissue without genomic reprogramming could be captured via olfactory biopsy. (
  • We sought to define the neural substrates of human olfactory information processing and determine how these are modulated by affective properties of odors. (
  • Neuroimaging studies have begun to identify important olfactory structures, but one notable feature is the inconsistent activation of piriform cortex ( Zald and Pardo, 2000 ). (
  • Huang Y , Tan F , Zhuo Y , Liu J , He J , Duan D , Lu M , Hu Z , . Hypoxia-preconditioned olfactory mucosa mesenchymal stem cells abolish cerebral ischemia/reperfusion-induced pyroptosis and apoptotic death of microglial cells by activating HIF-1α. (
  • Lesions of or removal of the vomeronasal organ did not disrupt the preferences of sexually satiated males for a novel female, but elimination of main olfactory system function by ZnSO4 treatment of the olfactory mucosa did abolish such preferences. (
  • Neuropeptide Y enhances olfactory mucosa responses to odorant in hungry rats. (
  • Thus olfactory cues are sufficient for individual discrimination of novel females by sexually satiated male hamsters, and such recognition leads to increased sexual arousal. (
  • Ongoing work explores how epithelial cells of the sinuses and olfactory mucosa participate in the immune response and contribute to chronic inflammation. (
  • Comparison of Olfactory Performance in Dogs and Humans. (
  • Ghrelin enhances olfactory sensitivity and exploratory sniffing in rodents and humans. (
  • Dysosmia (disagreeable or distorted sense of smell) may occur in patients with infection of the nasal sinuses, partial damage to the olfactory bulbs, or mental depression. (
  • The sense of smell is mediated through stimulation of the olfactory receptor cells by volatile chemicals. (
  • [ 3 ] A 2002 study showed that the prevalence of objective olfactory impairment in adults older than 53 years is 24.5% and grows more prevalent with age, reaching 62.5 % in those aged 80-97 years. (
  • We used event-related functional magnetic resonance imaging (fMRI) in an olfactory version of a classical conditioning paradigm, whereby neutral faces were paired with pleasant, neutral, or unpleasant odors, under 50% reinforcement. (
  • Neurosurgical treatment, including removal of the olfactory bulbs and tracts, resulted in permanent resolution of dysosmia. (
  • Odorants can also be perceived by entering the nose posteriorly through the nasopharynx to reach the olfactory receptor via retronasal olfaction. (
  • Methods: Histopathologic and immunocytochemical analysis of the olfactory bulbs was undertaken and compared with age-matched control tissue. (
  • The only known structure of the adult mammalian nervous system where axonal growth normally occurs is the olfactory nerve. (
  • Glands of the olfactory mucosa secrete a mostly serous fluid. (
  • Moreover, we obtained psychophysiological data on olfactory ability (Sniffin' Sticks, Food associated odor test) and self-report measurements on eating behavior. (
  • Since a body of literature implies that olfactory perception and function is hampered in obesity, we here investigate neuroanatomical correlates of this phenomenon. (
  • Hence, changes in olfactory perception might be involved in unhealthy eating and potentially lead to weight gain. (
  • Extrapolating from these values, there are currently 14 million older adults with some degree of olfactory impairment. (
  • Furthermore, acute NPY injection immediately rescues food-odour preference without additional training, indicating that NPY is required for reading olfactory circuits during behavioural expression rather than writing olfactory circuits during odour learning. (
  • Exposure to emissions from both renewable and fossil diesel significantly altered the expression of genes associated with inflammatory response, xenobiotic metabolism, olfactory signalling and olfactory mucosa integrity. (
  • verification needed] Adult stem cell harvesting Cells in the olfactory mucosa have been used in clinical trials for adult stem cell therapeutic treatments and successfully harvested for future applications. (
  • The study explored molecular-level changes occurring in human olfactory mucosa cells when exposed to different emissions derived from traffic. (
  • The olfactory mucosa cells used in the study were obtained from voluntary donors, collected in collaboration with Kuopio University Hospital. (
  • These processes are mediated by the main olfactory system but not the vomeronasal accessory-olfactory system. (
  • On this notion, it has been shown that individuals with obesity show several alterations in the olfactory system. (
  • The study is the first to combine an analysis of emissions from different diesel fuels and exhaust after-treatment systems with an examination of their effects in a human-derived cell model of the olfactory mucosa. (
  • The study, led by the University of Eastern Finland, is the first to combine an analysis of emissions from different diesel fuels and exhaust after-treatment systems with an examination of their effects in a human-derived cell model of the olfactory mucosa. (
  • One possible explanation would be the lesser expression of ACE2 in the nasal mucosa compared to adults with consequently less binding of SARS-CoV2. (
  • Odorants diffuse into the mucous and are transported to the olfactory receptor. (