In tissue culture, hairlike projections of neurons stimulated by growth factors and other molecules. These projections may go on to form a branched tree of dendrites or a single axon or they may be reabsorbed at a later stage of development. "Neurite" may refer to any filamentous or pointed outgrowth of an embryonal or tissue-culture neural cell.
Nerve fibers that are capable of rapidly conducting impulses away from the neuron cell body.
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 CELL LINE derived from a PHEOCHROMOCYTOMA of the rat ADRENAL MEDULLA. PC12 cells stop dividing and undergo terminal differentiation when treated with NERVE GROWTH FACTOR, making the line a useful model system for NERVE CELL differentiation.
Factors which enhance the growth potentialities of sensory and sympathetic nerve cells.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
Sensory ganglia located on the dorsal spinal roots within the vertebral column. The spinal ganglion cells are pseudounipolar. The single primary branch bifurcates sending a peripheral process to carry sensory information from the periphery and a central branch which relays that information to the spinal cord or brain.
Bulbous enlargement of the growing tip of nerve axons and dendrites. They are crucial to neuronal development because of their pathfinding ability and their role in synaptogenesis.
The developmental entity of a fertilized chicken egg (ZYGOTE). The developmental process begins about 24 h before the egg is laid at the BLASTODISC, a small whitish spot on the surface of the EGG YOLK. After 21 days of incubation, the embryo is fully developed before hatching.
Renewal or physiological repair of damaged nerve tissue.
'Nerve tissue proteins' are specialized proteins found within the nervous system's biological tissue, including neurofilaments, neuronal cytoskeletal proteins, and neural cell adhesion molecules, which facilitate structural support, intracellular communication, and synaptic connectivity essential for proper neurological function.
A dense intricate feltwork of interwoven fine glial processes, fibrils, synaptic terminals, axons, and dendrites interspersed among the nerve cells in the gray matter of the central nervous system.
A usually benign, well-encapsulated, lobular, vascular tumor of chromaffin tissue of the ADRENAL MEDULLA or sympathetic paraganglia. The cardinal symptom, reflecting the increased secretion of EPINEPHRINE and NOREPINEPHRINE, is HYPERTENSION, which may be persistent or intermittent. During severe attacks, there may be HEADACHE; SWEATING, palpitation, apprehension, TREMOR; PALLOR or FLUSHING of the face, NAUSEA and VOMITING, pain in the CHEST and ABDOMEN, and paresthesias of the extremities. The incidence of malignancy is as low as 5% but the pathologic distinction between benign and malignant pheochromocytomas is not clear. (Dorland, 27th ed; DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1298)
Ganglia of the sympathetic nervous system including the paravertebral and the prevertebral ganglia. Among these are the sympathetic chain ganglia, the superior, middle, and inferior cervical ganglia, and the aorticorenal, celiac, and stellate ganglia.
Abnormal structures located in various parts of the brain and composed of dense arrays of paired helical filaments (neurofilaments and microtubules). These double helical stacks of transverse subunits are twisted into left-handed ribbon-like filaments that likely incorporate the following proteins: (1) the intermediate filaments: medium- and high-molecular-weight neurofilaments; (2) the microtubule-associated proteins map-2 and tau; (3) actin; and (4) UBIQUITINS. As one of the hallmarks of ALZHEIMER DISEASE, the neurofibrillary tangles eventually occupy the whole of the cytoplasm in certain classes of cell in the neocortex, hippocampus, brain stem, and diencephalon. The number of these tangles, as seen in post mortem histology, correlates with the degree of dementia during life. Some studies suggest that tangle antigens leak into the systemic circulation both in the course of normal aging and in cases of Alzheimer disease.
Intracytoplasmic, eosinophilic, round to elongated inclusions found in vacuoles of injured or fragmented neurons. The presence of Lewy bodies is the histological marker of the degenerative changes in LEWY BODY DISEASE and PARKINSON DISEASE but they may be seen in other neurological conditions. They are typically found in the substantia nigra and locus coeruleus but they are also seen in the basal forebrain, hypothalamic nuclei, and neocortex.
NERVE GROWTH FACTOR is the first of a series of neurotrophic factors that were found to influence the growth and differentiation of sympathetic and sensory neurons. It is comprised of alpha, beta, and gamma subunits. The beta subunit is responsible for its growth stimulating activity.
The delicate interlacing threads, formed by aggregations of neurofilaments and neurotubules, coursing through the CYTOPLASM of the body of a NEURON and extending from one DENDRITE into another or into the AXON.
Annelids of the class Hirudinea. Some species, the bloodsuckers, may become temporarily parasitic upon animals, including man. Medicinal leeches (HIRUDO MEDICINALIS) have been used therapeutically for drawing blood since ancient times.
Microtubule-associated proteins that are mainly expressed in neurons. Tau proteins constitute several isoforms and play an important role in the assembly of tubulin monomers into microtubules and in maintaining the cytoskeleton and axonal transport. Aggregation of specific sets of tau proteins in filamentous inclusions is the common feature of intraneuronal and glial fibrillar lesions (NEUROFIBRILLARY TANGLES; NEUROPIL THREADS) in numerous neurodegenerative disorders (ALZHEIMER DISEASE; TAUOPATHIES).
A common neoplasm of early childhood arising from neural crest cells in the sympathetic nervous system, and characterized by diverse clinical behavior, ranging from spontaneous remission to rapid metastatic progression and death. This tumor is the most common intraabdominal malignancy of childhood, but it may also arise from thorax, neck, or rarely occur in the central nervous system. Histologic features include uniform round cells with hyperchromatic nuclei arranged in nests and separated by fibrovascular septa. Neuroblastomas may be associated with the opsoclonus-myoclonus syndrome. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, pp2099-2101; Curr Opin Oncol 1998 Jan;10(1):43-51)
A curved elevation of GRAY MATTER extending the entire length of the floor of the TEMPORAL HORN of the LATERAL VENTRICLE (see also TEMPORAL LOBE). The hippocampus proper, subiculum, and DENTATE GYRUS constitute the hippocampal formation. Sometimes authors include the ENTORHINAL CORTEX in the hippocampal formation.
A synuclein that is a major component of LEWY BODIES that plays a role in neurodegeneration and neuroprotection.
Accumulations of extracellularly deposited AMYLOID FIBRILS within tissues.
Slender, cylindrical filaments found in the cytoskeleton of plant and animal cells. They are composed of the protein TUBULIN and are influenced by TUBULIN MODULATORS.
A microtubule subunit protein found in large quantities in mammalian brain. It has also been isolated from SPERM FLAGELLUM; CILIA; and other sources. Structurally, the protein is a dimer with a molecular weight of approximately 120,000 and a sedimentation coefficient of 5.8S. It binds to COLCHICINE; VINCRISTINE; and VINBLASTINE.
A degenerative disease of the BRAIN characterized by the insidious onset of DEMENTIA. Impairment of MEMORY, judgment, attention span, and problem solving skills are followed by severe APRAXIAS and a global loss of cognitive abilities. The condition primarily occurs after age 60, and is marked pathologically by severe cortical atrophy and the triad of SENILE PLAQUES; NEUROFIBRILLARY TANGLES; and NEUROPIL THREADS. (From Adams et al., Principles of Neurology, 6th ed, pp1049-57)
Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.
Type III intermediate filament proteins that assemble into neurofilaments, the major cytoskeletal element in nerve axons and dendrites. They consist of three distinct polypeptides, the neurofilament triplet. Types I, II, and IV intermediate filament proteins form other cytoskeletal elements such as keratins and lamins. It appears that the metabolism of neurofilaments is disturbed in Alzheimer's disease, as indicated by the presence of neurofilament epitopes in the neurofibrillary tangles, as well as by the severe reduction of the expression of the gene for the light neurofilament subunit of the neurofilament triplet in brains of Alzheimer's patients. (Can J Neurol Sci 1990 Aug;17(3):302)
Histochemical localization of immunoreactive substances using labeled antibodies as reagents.
Surface ligands that mediate cell-to-cell adhesion and function in the assembly and interconnection of the vertebrate nervous system. These molecules promote cell adhesion via a homophilic mechanism. These are not to be confused with NEURAL CELL ADHESION MOLECULES, now known to be expressed in a variety of tissues and cell types in addition to nervous tissue.
A form of interference microscopy in which variations of the refracting index in the object are converted into variations of intensity in the image. This is achieved by the action of a phase plate.
Large, noncollagenous glycoprotein with antigenic properties. It is localized in the basement membrane lamina lucida and functions to bind epithelial cells to the basement membrane. Evidence suggests that the protein plays a role in tumor invasion.
The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.
The directed transport of ORGANELLES and molecules along nerve cell AXONS. Transport can be anterograde (from the cell body) or retrograde (toward the cell body). (Alberts et al., Molecular Biology of the Cell, 3d ed, pG3)
The sensory ganglion of the COCHLEAR NERVE. The cells of the spiral ganglion send fibers peripherally to the cochlear hair cells and centrally to the COCHLEAR NUCLEI of the BRAIN STEM.
Neuroglial cells of the peripheral nervous system which form the insulating myelin sheaths of peripheral axons.
High molecular weight proteins found in the MICROTUBULES of the cytoskeletal system. Under certain conditions they are required for TUBULIN assembly into the microtubules and stabilize the assembled microtubules.
Loss of functional activity and trophic degeneration of nerve axons and their terminal arborizations following the destruction of their cells of origin or interruption of their continuity with these cells. The pathology is characteristic of neurodegenerative diseases. Often the process of nerve degeneration is studied in research on neuroanatomical localization and correlation of the neurophysiology of neural pathways.
Extensions of the nerve cell body. They are short and branched and receive stimuli from other NEURONS.
A family of homologous proteins of low MOLECULAR WEIGHT that are predominately expressed in the BRAIN and that have been implicated in a variety of human diseases. They were originally isolated from CHOLINERGIC FIBERS of TORPEDO.
The ten-layered nervous tissue membrane of the eye. It is continuous with the OPTIC NERVE and receives images of external objects and transmits visual impulses to the brain. Its outer surface is in contact with the CHOROID and the inner surface with the VITREOUS BODY. The outer-most layer is pigmented, whereas the inner nine layers are transparent.
Specialized junctions at which a neuron communicates with a target cell. At classical synapses, a neuron's presynaptic terminal releases a chemical transmitter stored in synaptic vesicles which diffuses across a narrow synaptic cleft and activates receptors on the postsynaptic membrane of the target cell. The target may be a dendrite, cell body, or axon of another neuron, or a specialized region of a muscle or secretory cell. Neurons may also communicate via direct electrical coupling with ELECTRICAL SYNAPSES. Several other non-synaptic chemical or electric signal transmitting processes occur via extracellular mediated interactions.
A nervous tissue specific protein which is highly expressed in NEURONS during development and NERVE REGENERATION. It has been implicated in neurite outgrowth, long-term potentiation, SIGNAL TRANSDUCTION, and NEUROTRANSMITTER release. (From Neurotoxicology 1994;15(1):41-7) It is also a substrate of PROTEIN KINASE C.
A single-pass type I membrane protein. It is cleaved by AMYLOID PRECURSOR PROTEIN SECRETASES to produce peptides of varying amino acid lengths. A 39-42 amino acid peptide, AMYLOID BETA-PEPTIDES is a principal component of the extracellular amyloid in SENILE PLAQUES.
Test for tissue antigen using either a direct method, by conjugation of antibody with fluorescent dye (FLUORESCENT ANTIBODY TECHNIQUE, DIRECT) or an indirect method, by formation of antigen-antibody complex which is then labeled with fluorescein-conjugated anti-immunoglobulin antibody (FLUORESCENT ANTIBODY TECHNIQUE, INDIRECT). The tissue is then examined by fluorescence microscopy.
The network of filaments, tubules, and interconnecting filamentous bridges which give shape, structure, and organization to the cytoplasm.
Ganglia of the parasympathetic nervous system, including the ciliary, pterygopalatine, submandibular, and otic ganglia in the cranial region and intrinsic (terminal) ganglia associated with target organs in the thorax and abdomen.
Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.
A cylindrical column of tissue that lies within the vertebral canal. It is composed of WHITE MATTER and GRAY MATTER.
A contactin subtype that plays a role in axon outgrowth, axon fasciculation, and neuronal migration.
Nocodazole is an antineoplastic agent which exerts its effect by depolymerizing microtubules.
Tumors or cancer of the ADRENAL GLANDS.
The thin layer of GRAY MATTER on the surface of the CEREBRAL HEMISPHERES that develops from the TELENCEPHALON and folds into gyri and sulchi. It reaches its highest development in humans and is responsible for intellectual faculties and higher mental functions.
Peptides generated from AMYLOID BETA-PEPTIDES PRECURSOR. An amyloid fibrillar form of these peptides is the major component of amyloid plaques found in individuals with Alzheimer's disease and in aged individuals with trisomy 21 (DOWN SYNDROME). The peptide is found predominantly in the nervous system, but there have been reports of its presence in non-neural tissue.
An opisthobranch mollusk of the order Anaspidea. It is used frequently in studies of nervous system development because of its large identifiable neurons. Aplysiatoxin and its derivatives are not biosynthesized by Aplysia, but acquired by ingestion of Lyngbya (seaweed) species.
Cytoplasmic filaments intermediate in diameter (about 10 nanometers) between the microfilaments and the microtubules. They may be composed of any of a number of different proteins and form a ring around the cell nucleus.
A light microscopic technique in which only a small spot is illuminated and observed at a time. An image is constructed through point-by-point scanning of the field in this manner. Light sources may be conventional or laser, and fluorescence or transmitted observations are possible.
Elements of limited time intervals, contributing to particular results or situations.
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.
Nerve fibers liberating catecholamines at a synapse after an impulse.
Refers to animals in the period of time just after birth.
Clusters of multipolar neurons surrounded by a capsule of loosely organized CONNECTIVE TISSUE located outside the CENTRAL NERVOUS SYSTEM.
The main information-processing organs of the nervous system, consisting of the brain, spinal cord, and meninges.
A technique of culturing mixed cell types in vitro to allow their synergistic or antagonistic interactions, such as on CELL DIFFERENTIATION or APOPTOSIS. Coculture can be of different types of cells, tissues, or organs from normal or disease states.
Sulfur compounds in which the sulfur atom is attached to three organic radicals and an electronegative element or radical.
Orientation of intracellular structures especially with respect to the apical and basolateral domains of the plasma membrane. Polarized cells must direct proteins from the Golgi apparatus to the appropriate domain since tight junctions prevent proteins from diffusing between the two domains.
A dynamic actin-rich extension of the surface of an animal cell used for locomotion or prehension of food.
A cyclic nucleotide derivative that mimics the action of endogenous CYCLIC AMP and is capable of permeating the cell membrane. It has vasodilator properties and is used as a cardiac stimulant. (From Merck Index, 11th ed)
A neurodegenerative disease characterized by dementia, mild parkinsonism, and fluctuations in attention and alertness. The neuropsychiatric manifestations tend to precede the onset of bradykinesia, MUSCLE RIGIDITY, and other extrapyramidal signs. DELUSIONS and visual HALLUCINATIONS are relatively frequent in this condition. Histologic examination reveals LEWY BODIES in the CEREBRAL CORTEX and BRAIN STEM. SENILE PLAQUES and other pathologic features characteristic of ALZHEIMER DISEASE may also be present. (From Neurology 1997;48:376-380; Neurology 1996;47:1113-1124)
Any of several ways in which living cells of an organism communicate with one another, whether by direct contact between cells or by means of chemical signals carried by neurotransmitter substances, hormones, and cyclic AMP.
Methods of maintaining or growing biological materials in controlled laboratory conditions. These include the cultures of CELLS; TISSUES; organs; or embryo in vitro. Both animal and plant tissues may be cultured by a variety of methods. Cultures may derive from normal or abnormal tissues, and consist of a single cell type or mixed cell types.
Transection or severing of an axon. This type of denervation is used often in experimental studies on neuronal physiology and neuronal death or survival, toward an understanding of nervous system disease.
11- to 14-membered macrocyclic lactones with a fused isoindolone. Members with INDOLES attached at the C10 position are called chaetoglobosins. They are produced by various fungi. Some members interact with ACTIN and inhibit CYTOKINESIS.
Filamentous proteins that are the main constituent of the thin filaments of muscle fibers. The filaments (known also as filamentous or F-actin) can be dissociated into their globular subunits; each subunit is composed of a single polypeptide 375 amino acids long. This is known as globular or G-actin. In conjunction with MYOSINS, actin is responsible for the contraction and relaxation of muscle.
The sensory ganglion of the facial (7th cranial) nerve. The geniculate ganglion cells send central processes to the brain stem and peripheral processes to the taste buds in the anterior tongue, the soft palate, and the skin of the external auditory meatus and the mastoid process.
The largest and uppermost of the paravertebral sympathetic ganglia.
Formation of NEURONS which involves the differentiation and division of STEM CELLS in which one or both of the daughter cells become neurons.
Extracellular protease inhibitors that are secreted from FIBROBLASTS. They form a covalent complex with SERINE PROTEASES and can mediate their cellular internalization and degradation.
Methods used to label and follow the course of NEURAL PATHWAYS by AXONAL TRANSPORT of injected NEURONAL TRACT-TRACERS.
The part of brain that lies behind the BRAIN STEM in the posterior base of skull (CRANIAL FOSSA, POSTERIOR). It is also known as the "little brain" with convolutions similar to those of CEREBRAL CORTEX, inner white matter, and deep cerebellar nuclei. Its function is to coordinate voluntary movements, maintain balance, and learn motor skills.
Neurons of the innermost layer of the retina, the internal plexiform layer. They are of variable sizes and shapes, and their axons project via the OPTIC NERVE to the brain. A small subset of these cells act as photoreceptors with projections to the SUPRACHIASMATIC NUCLEUS, the center for regulating CIRCADIAN RHYTHM.
A family of immunoglobulin-related cell adhesion molecules that are involved in NERVOUS SYSTEM patterning.
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.
Growth processes that result in an increase in CELL SIZE.
Established cell cultures that have the potential to propagate indefinitely.
The prototypical and most well-studied member of the semaphorin family. Semaphorin-3A is an axon-repulsive guidance cue for migrating neurons in the developing nervous system. It has so far been found only in vertebrates, and binds to NEUROPILIN-1/plexin complex receptors on growth cones. Like other class 3 semaphorins, it is a secreted protein.
A nerve which originates in the lumbar and sacral spinal cord (L4 to S3) and supplies motor and sensory innervation to the lower extremity. The sciatic nerve, which is the main continuation of the sacral plexus, is the largest nerve in the body. It has two major branches, the TIBIAL NERVE and the PERONEAL NERVE.
Neurons which activate MUSCLE CELLS.
The quality of surface form or outline of CELLS.
Protein analogs and derivatives of the Aequorea victoria green fluorescent protein that emit light (FLUORESCENCE) when excited with ULTRAVIOLET RAYS. They are used in REPORTER GENES in doing GENETIC TECHNIQUES. Numerous mutants have been made to emit other colors or be sensitive to pH.
A GLYCOINOSITOL PHOSPHOLIPID MEMBRANE ANCHOR containing ephrin found in developing tectum. It has been shown to mediate the bundling of cortical axons and repel the axonal growth of retinal ganglia axons. It is found in a variety of adult tissues of BRAIN; HEART; and KIDNEY.
A generic term for any circumscribed mass of foreign (e.g., lead or viruses) or metabolically inactive materials (e.g., ceroid or MALLORY BODIES), within the cytoplasm or nucleus of a cell. Inclusion bodies are in cells infected with certain filtrable viruses, observed especially in nerve, epithelial, or endothelial cells. (Stedman, 25th ed)
The entire nerve apparatus, composed of a central part, the brain and spinal cord, and a peripheral part, the cranial and spinal nerves, autonomic ganglia, and plexuses. (Stedman, 26th ed)
Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.
The process of moving proteins from one cellular compartment (including extracellular) to another by various sorting and transport mechanisms such as gated transport, protein translocation, and vesicular transport.
Laboratory mice that have been produced from a genetically manipulated EGG or EMBRYO, MAMMALIAN.
The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.
Differentiated tissue of the central nervous system composed of NERVE CELLS, fibers, DENDRITES, and specialized supporting cells.
Treatment of muscles and nerves under pressure as a result of crush injuries.
A class of large neuroglial (macroglial) cells in the central nervous system - the largest and most numerous neuroglial cells in the brain and spinal cord. Astrocytes (from "star" cells) are irregularly shaped with many long processes, including those with "end feet" which form the glial (limiting) membrane and directly and indirectly contribute to the BLOOD-BRAIN BARRIER. They regulate the extracellular ionic and chemical environment, and "reactive astrocytes" (along with MICROGLIA) respond to injury.
Clusters of neuronal cell bodies in invertebrates. Invertebrate ganglia may also contain neuronal processes and non-neuronal supporting cells. Many invertebrate ganglia are favorable subjects for research because they have small numbers of functional neuronal types which can be identified from one animal to another.

Ral-specific guanine nucleotide exchange factor activity opposes other Ras effectors in PC12 cells by inhibiting neurite outgrowth. (1/2773)

Ras proteins can activate at least three classes of downstream target proteins: Raf kinases, phosphatidylinositol-3 phosphate (PI3) kinase, and Ral-specific guanine nucleotide exchange factors (Ral-GEFs). In NIH 3T3 cells, activated Ral-GEFs contribute to Ras-induced cell proliferation and oncogenic transformation by complementing the activities of Raf and PI3 kinases. In PC12 cells, activated Raf and PI3 kinases mediate Ras-induced cell cycle arrest and differentiation into a neuronal phenotype. Here, we show that in PC12 cells, Ral-GEF activity acts opposite to other Ras effectors. Elevation of Ral-GEF activity induced by transfection of a mutant Ras protein that preferentially activates Ral-GEFs, or by transfection of the catalytic domain of the Ral-GEF Rgr, suppressed cell cycle arrest and neurite outgrowth induced by nerve growth factor (NGF) treatment. In addition, Rgr reduced neurite outgrowth induced by a mutant Ras protein that preferentially activates Raf kinases. Furthermore, inhibition of Ral-GEF activity by expression of a dominant negative Ral mutant accelerated cell cycle arrest and enhanced neurite outgrowth in response to NGF treatment. Ral-GEF activity may function, at least in part, through inhibition of the Rho family GTPases, CDC42 and Rac. In contrast to Ras, which was activated for hours by NGF treatment, Ral was activated for only approximately 20 min. These findings suggest that one function of Ral-GEF signaling induced by NGF is to delay the onset of cell cycle arrest and neurite outgrowth induced by other Ras effectors. They also demonstrate that Ras has the potential to promote both antidifferentiation and prodifferentiation signaling pathways through activation of distinct effector proteins. Thus, in some cell types the ratio of activities among Ras effectors and their temporal regulation may be important determinants for cell fate decisions between proliferation and differentiation.  (+info)

Hyperoxia induces the neuronal differentiated phenotype of PC12 cells via a sustained activity of mitogen-activated protein kinase induced by Bcl-2. (2/2773)

We previously reported that rat pheochromocytoma PC12 cells express the neuronal differentiated phenotype under hyperoxia through the production of reactive oxygen species (ROS). In the present study, we found that in this phenotype, Bcl-2, an apoptosis inhibitor, affects mitogen-activated protein (MAP)-kinase activity, which is known as a key enzyme of the signal-transduction cascade for differentiation. When PC12 cells were cultured under hyperoxia, a rapid increase in MAP-kinase activity, including that of both p42 and p44, was observed. Although the activity level then decreased quickly, activity higher than the control level was observed for 48 h. PD98059, an inhibitor of MAP kinase, suppressed the hyperoxia-induced neurite extensions, suggesting the involvement of MAP-kinase activity in the mechanism of differentiation induced by ROS. An elevation of Bcl-2 expression was observed after culturing PC12 cells for 24 h under hyperoxia. This Bcl-2 elevation was not affected by treatment with PD98059, suggesting that it did not directly induce neurite extension under hyperoxia. However, the blockade of the Bcl-2 elevation by an antisense oligonucleotide inhibited the sustained MAP-kinase activity and neurite extensions under hyperoxia. Further, in PC12 cells highly expressing Bcl-2, the sustained MAP-kinase activity and neurite extensions under hyperoxia were enhanced. These results suggested that MAP kinase is activated through the production of ROS, and the subsequent elevation of Bcl-2 expression sustains the MAP-kinase activity, resulting in the induction of the neuronal-differentiation phenotype of PC12 cells under hyperoxia.  (+info)

Characterization of elementary Ca2+ release signals in NGF-differentiated PC12 cells and hippocampal neurons. (3/2773)

Elementary Ca2+ release signals in nerve growth factor- (NGF-) differentiated PC12 cells and hippocampal neurons, functionally analogous to the "Ca2+ sparks" and "Ca2+ puffs" identified in other cell types, were characterized by confocal microscopy. They either occurred spontaneously or could be activated by caffeine and metabotropic agonists. The release events were dissimilar to the sparks and puffs described so far, as many arose from clusters of both ryanodine receptors (RyRs) and inositol 1,4,5-trisphosphate receptors (InsP3Rs). Increasing either the stimulus strength or loading of the intracellular stores enhanced the frequency of and coupling between elementary release sites and evoked global Ca2+ signals. In the PC12 cells, the elementary Ca2+ release preferentially occurred around the branch points. Spatio-temporal recruitment of such elementary release events may regulate neuronal activities.  (+info)

Neurite outgrowth-regulating properties of GABA and the effect of serum on mouse spinal cord neurons in culture. (4/2773)

Time-lapse photography was used to examine the effects of gamma-aminobutyric acid (GABA) on the outgrowth and motility of neurites in cultures from mouse spinal cord. GABA at concentrations of 100, 10 and 1 microM caused significant inhibition of neurite outgrowth and the motility of growth cones was significantly reduced by treatment with 100 and 10 microM GABA. This effect was mimicked by the GABA(B) receptor agonist baclofen, whereas the GABA(A) receptor agonist muscimol had no effect. The effect of GABA on outgrowth and motility seems to be dependent on the type of serum employed. The results reported here were obtained only when heat-inactivated serum was used and not when non heat-inactivated serum was added to the culture medium. They suggest that GABA has a role in the regulation of process outgrowth within the embryonic mouse spinal cord.  (+info)

Human nerve growth factor beta (hNGF-beta): mammary gland specific expression and production in transgenic rabbits. (5/2773)

Transgenic rabbits carrying gene constructs encoding human nerve growth factor beta (hNGF-beta) cDNA were generated. Expression of hNGF-beta mRNA was restricted to the mammary gland of lactating rabbits. Western Blot analysis revealed a polypeptide of 13.2 kDa in the milk of transgenic animals. hNGF-beta was purified from the milk by a two-step chromatographic procedure. Electrospray mass spectroscopy analysis of purified hNGF-beta depicted a molecular weight of 13,261 Da per subunit. The biological activity of the hNGF-beta was tested using PC12W2 cells and cultures of dorsal root ganglion neurons from chicken embryos. Crude defatted milk from transgenic animals and purified hNGF-beta demonstrated full biological activity when compared to commercial recombinant hNGF-beta.  (+info)

ELAV tumor antigen, Hel-N1, increases translation of neurofilament M mRNA and induces formation of neurites in human teratocarcinoma cells. (6/2773)

Human ELAV proteins are implicated in cell growth and differentiation via regulation of mRNA expression in the cytoplasm. In human embryonic teratocarcinoma (hNT2) cells transfected with the human neuronal ELAV-like protein, Hel-N1, neurites formed, yet cells were not terminally differentiated. Cells in which neurite formation was associated with Hel-N1 overexpression, also expressed increased levels of endogenous neurofilament M (NF-M) protein, which distributed along the neurites. However, steady-state levels of NF-M mRNA remained similar whether or not hNT2 cells were transfected with Hel-N1. These findings suggest that turnover of NF-M mRNA was not affected by Hel-N1 expression, despite the fact that Hel-N1 can bind to the 3' UTR of NF-M mRNA and was found directly associated with NF-M mRNA in transfected cells. Analysis of the association of NF-M mRNA with the translational apparatus in Hel-N1 transfectants showed nearly complete recruitment to heavy polysomes, indicating that Hel-N1 caused an increase in translational initiation. Our results suggest that the stability and/or translation of ARE-containing mRNAs can be regulated independently by the ELAV protein, Hel-N1, depending upon sequence elements in the 3' UTRs and upon the inherent turnover rates of the mRNAs that are bound to Hel-N1 in vivo.  (+info)

Myelin and collapsin-1 induce motor neuron growth cone collapse through different pathways: inhibition of collapse by opposing mutants of rac1. (7/2773)

Precise growth cone guidance is the consequence of a continuous reorganization of actin filament structures within filopodia and lamellipodia in response to inhibitory and promoting cues. The small GTPases rac1, cdc42, and rhoA are critical for regulating distinct actin structures in non-neuronal cells and presumably in growth cones. Collapse, a retraction of filopodia and lamellipodia, is a typical growth cone behavior on contact with inhibitory cues and is associated with depolymerization and redistribution of actin filaments. We examined whether small GTPases mediate the inhibitory properties of CNS myelin or collapsin-1, a soluble semaphorin, in chick embryonic motor neuron cultures. As demonstrated for collapsin-1, CNS myelin-evoked growth cone collapse was accompanied by a reduction of rhodamine-phalloidin staining most prominent in the growth cone periphery, suggesting actin filament disassembly. Specific mutants of small GTPases were capable of desensitizing growth cones to CNS myelin or collapsin-1. Adenoviral-mediated expression of constitutively active rac1 or rhoA abolished CNS myelin-induced collapse and allowed remarkable neurite extension on a CNS myelin substrate. In contrast, expression of dominant negative rac1 or cdc42 negated collapsin-1-induced growth cone collapse and promoted neurite outgrowth on a collapsin-1 substrate. These findings suggest that small GTPases can modulate the signaling pathways of inhibitory stimuli and, consequently, allow the manipulation of growth cone behavior. However, the fact that opposite mutants of rac1 were effective against different inhibitory stimuli speaks against a universal signaling pathway underlying growth cone collapse.  (+info)

Specification of distinct dopaminergic neural pathways: roles of the Eph family receptor EphB1 and ligand ephrin-B2. (8/2773)

Dopaminergic neurons in the substantia nigra and ventral tegmental area project to the caudate putamen and nucleus accumbens/olfactory tubercle, respectively, constituting mesostriatal and mesolimbic pathways. The molecular signals that confer target specificity of different dopaminergic neurons are not known. We now report that EphB1 and ephrin-B2, a receptor and ligand of the Eph family, are candidate guidance molecules for the development of these distinct pathways. EphB1 and ephrin-B2 are expressed in complementary patterns in the midbrain dopaminergic neurons and their targets, and the ligand specifically inhibits the growth of neurites and induces the cell loss of substantia nigra, but not ventral tegmental, dopaminergic neurons. These studies suggest that the ligand-receptor pair may contribute to the establishment of distinct neural pathways by selectively inhibiting the neurite outgrowth and cell survival of mistargeted neurons. In addition, we show that ephrin-B2 expression is upregulated by cocaine and amphetamine in adult mice, suggesting that ephrin-B2/EphB1 interaction may play a role in drug-induced plasticity in adults as well.  (+info)

Neurites are extensions of a neuron (a type of cell in the nervous system) that can be either an axon or a dendrite. An axon is a thin, cable-like extension that carries signals away from the cell body, while a dendrite is a branching extension that receives signals from other neurons. Neurites play a crucial role in the communication between neurons and the formation of neural networks. They are involved in the transmission of electrical and chemical signals, as well as in the growth and development of the nervous system.

An axon is a long, slender extension of a neuron (a type of nerve cell) that conducts electrical impulses (nerve impulses) away from the cell body to target cells, such as other neurons or muscle cells. Axons can vary in length from a few micrometers to over a meter long and are typically surrounded by a myelin sheath, which helps to insulate and protect the axon and allows for faster transmission of nerve impulses.

Axons play a critical role in the functioning of the nervous system, as they provide the means by which neurons communicate with one another and with other cells in the body. Damage to axons can result in serious neurological problems, such as those seen in spinal cord injuries or neurodegenerative diseases like multiple sclerosis.

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.

PC12 cells are a type of rat pheochromocytoma cell line, which are commonly used in scientific research. Pheochromocytomas are tumors that develop from the chromaffin cells of the adrenal gland, and PC12 cells are a subtype of these cells.

PC12 cells have several characteristics that make them useful for research purposes. They can be grown in culture and can be differentiated into a neuron-like phenotype when treated with nerve growth factor (NGF). This makes them a popular choice for studies involving neuroscience, neurotoxicity, and neurodegenerative disorders.

PC12 cells are also known to express various neurotransmitter receptors, ion channels, and other proteins that are relevant to neuronal function, making them useful for studying the mechanisms of drug action and toxicity. Additionally, PC12 cells can be used to study the regulation of cell growth and differentiation, as well as the molecular basis of cancer.

Nerve Growth Factors (NGFs) are a family of proteins that play an essential role in the growth, maintenance, and survival of certain neurons (nerve cells). They were first discovered by Rita Levi-Montalcini and Stanley Cohen in 1956. NGF is particularly crucial for the development and function of the peripheral nervous system, which connects the central nervous system to various organs and tissues throughout the body.

NGF supports the differentiation and survival of sympathetic and sensory neurons during embryonic development. In adults, NGF continues to regulate the maintenance and repair of these neurons, contributing to neuroplasticity – the brain's ability to adapt and change over time. Additionally, NGF has been implicated in pain transmission and modulation, as well as inflammatory responses.

Abnormal levels or dysfunctional NGF signaling have been associated with various medical conditions, including neurodegenerative diseases (e.g., Alzheimer's and Parkinson's), chronic pain disorders, and certain cancers (e.g., small cell lung cancer). Therefore, understanding the role of NGF in physiological and pathological processes may provide valuable insights into developing novel therapeutic strategies for these conditions.

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

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

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

Spinal ganglia, also known as dorsal root ganglia, are clusters of nerve cell bodies located in the peripheral nervous system. They are situated along the length of the spinal cord and are responsible for transmitting sensory information from the body to the brain. Each spinal ganglion contains numerous neurons, or nerve cells, with long processes called axons that extend into the periphery and innervate various tissues and organs. The cell bodies within the spinal ganglia receive sensory input from these axons and transmit this information to the central nervous system via the dorsal roots of the spinal nerves. This allows the brain to interpret and respond to a wide range of sensory stimuli, including touch, temperature, pain, and proprioception (the sense of the position and movement of one's body).

Growth cones are specialized structures found at the tips of growing neurites (axons and dendrites) during the development and regeneration of the nervous system. They were first described by Santiago Ramón y Cajal in the late 19th century. Growth cones play a crucial role in the process of neurogenesis, guiding the extension and pathfinding of axons to their appropriate targets through a dynamic interplay with environmental cues. These cues include various guidance molecules, such as netrins, semaphorins, ephrins, and slits, which bind to receptors on the growth cone membrane and trigger intracellular signaling cascades that ultimately determine the direction of axonal outgrowth.

Morphologically, a growth cone consists of three main parts: the central domain (or "C-domain"), the peripheral domain (or "P-domain"), and the transition zone connecting them. The C-domain contains microtubules and neurofilaments, which provide structural support and transport materials to the growing neurite. The P-domain is rich in actin filaments and contains numerous membrane protrusions called filopodia and lamellipodia, which explore the environment for guidance cues and facilitate motility.

The dynamic behavior of growth cones allows them to navigate complex environments, make decisions at choice points, and ultimately form precise neural circuits during development. Understanding the mechanisms that regulate growth cone function is essential for developing strategies to promote neural repair and regeneration in various neurological disorders and injuries.

A chick embryo refers to the developing organism that arises from a fertilized chicken egg. It is often used as a model system in biological research, particularly during the stages of development when many of its organs and systems are forming and can be easily observed and manipulated. The study of chick embryos has contributed significantly to our understanding of various aspects of developmental biology, including gastrulation, neurulation, organogenesis, and pattern formation. Researchers may use various techniques to observe and manipulate the chick embryo, such as surgical alterations, cell labeling, and exposure to drugs or other agents.

Nerve regeneration is the process of regrowth and restoration of functional nerve connections following damage or injury to the nervous system. This complex process involves various cellular and molecular events, such as the activation of support cells called glia, the sprouting of surviving nerve fibers (axons), and the reformation of neural circuits. The goal of nerve regeneration is to enable the restoration of normal sensory, motor, and autonomic functions impaired due to nerve damage or injury.

Nerve tissue proteins are specialized proteins found in the nervous system that provide structural and functional support to nerve cells, also known as neurons. These proteins include:

1. Neurofilaments: These are type IV intermediate filaments that provide structural support to neurons and help maintain their shape and size. They are composed of three subunits - NFL (light), NFM (medium), and NFH (heavy).

2. Neuronal Cytoskeletal Proteins: These include tubulins, actins, and spectrins that provide structural support to the neuronal cytoskeleton and help maintain its integrity.

3. Neurotransmitter Receptors: These are specialized proteins located on the postsynaptic membrane of neurons that bind neurotransmitters released by presynaptic neurons, triggering a response in the target cell.

4. Ion Channels: These are transmembrane proteins that regulate the flow of ions across the neuronal membrane and play a crucial role in generating and transmitting electrical signals in neurons.

5. Signaling Proteins: These include enzymes, receptors, and adaptor proteins that mediate intracellular signaling pathways involved in neuronal development, differentiation, survival, and death.

6. Adhesion Proteins: These are cell surface proteins that mediate cell-cell and cell-matrix interactions, playing a crucial role in the formation and maintenance of neural circuits.

7. Extracellular Matrix Proteins: These include proteoglycans, laminins, and collagens that provide structural support to nerve tissue and regulate neuronal migration, differentiation, and survival.

Neuropil refers to the complex network of interwoven nerve cell processes (dendrites, axons, and their synaptic connections) in the central nervous system that forms the basis for information processing and transmission. It is the part of the brain or spinal cord where the neuronal cell bodies are not present, and it mainly consists of unmyelinated axons, dendrites, and synapses. Neuropil plays a crucial role in neural communication and is often the site of various neurochemical interactions.

Pheochromocytoma is a rare type of tumor that develops in the adrenal glands, which are triangular-shaped glands located on top of each kidney. These tumors produce excessive amounts of hormones called catecholamines, including adrenaline and noradrenaline. This can lead to a variety of symptoms such as high blood pressure, sweating, headaches, rapid heartbeat, and anxiety.

Pheochromocytomas are typically slow-growing and can be benign or malignant (cancerous). While the exact cause of these tumors is not always known, some genetic factors have been identified that may increase a person's risk. Treatment usually involves surgical removal of the tumor, along with medications to manage symptoms and control blood pressure before and after surgery.

Sympathetic ganglia are part of the autonomic nervous system, which controls involuntary bodily functions. These ganglia are clusters of nerve cell bodies located outside the central nervous system, along the spinal cord. They serve as a relay station for signals sent from the central nervous system to the organs and glands. The sympathetic ganglia are responsible for the "fight or flight" response, releasing neurotransmitters such as norepinephrine that prepare the body for action in response to stress or danger.

Neurofibrillary tangles are a pathological hallmark of several neurodegenerative disorders, most notably Alzheimer's disease. They are intracellular inclusions composed of abnormally phosphorylated and aggregated tau protein, which forms paired helical filaments. These tangles accumulate within the neurons, leading to their dysfunction and eventual death. The presence and density of neurofibrillary tangles are strongly associated with cognitive decline and disease progression in Alzheimer's disease and other related dementias.

Lewy bodies are abnormal aggregates of alpha-synuclein protein that develop in nerve cells (neurons) in the brain. They are named after Frederick Lewy, a German-American neurologist who discovered them while working with Dr. Alois Alzheimer. The presence of Lewy bodies is a hallmark feature of Lewy body dementia, which includes both Parkinson's disease dementia and dementia with Lewy bodies.

Lewy bodies can lead to the dysfunction and death of neurons in areas of the brain that control movement, cognition, and behavior. This can result in a range of symptoms, including motor impairments, cognitive decline, visual hallucinations, and mood changes. The exact role of Lewy bodies in the development and progression of these disorders is not fully understood, but they are believed to contribute to the neurodegenerative process that underlies these conditions.

Nerve Growth Factor (NGF) is a small secreted protein that is involved in the growth, maintenance, and survival of certain neurons (nerve cells). It was the first neurotrophin to be discovered and is essential for the development and function of the nervous system. NGF binds to specific receptors on the surface of nerve cells and helps to promote their differentiation, axonal growth, and synaptic plasticity. Additionally, NGF has been implicated in various physiological processes such as inflammation, immune response, and wound healing. Deficiencies or excesses of NGF have been linked to several neurological disorders, including Alzheimer's disease, Parkinson's disease, and pain conditions.

Neurofibrils are thin, thread-like structures found within the cytoplasm of nerve cells (neurons). They are primarily composed of various proteins and are involved in maintaining the structure and function of neurons. Neurofibrils include two types: neurofilaments and microtubule-associated protein tau (TAU) proteins.

Neurofilaments are intermediate filaments that provide structural support to neurons, while TAU proteins are involved in microtubule assembly, stability, and intracellular transport. Abnormal accumulation and aggregation of these proteins can lead to neurodegenerative disorders, such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis (ALS).

Leeches are parasitic worms that belong to the family Hirudinidae and the phylum Annelida. They are typically cylindrical in shape, have a suction cup at both ends, and possess rows of sharp teeth that allow them to attach to a host and feed on their blood.

In a medical context, leeches have been used for therapeutic purposes in a practice known as hirudotherapy. This technique involves applying leeches to certain parts of the body to draw out blood and promote healing. The saliva of some leech species contains substances that act as anticoagulants, which can help improve circulation and reduce swelling in the affected area.

However, it's important to note that the use of leeches for medical purposes is not without risks, including infection and allergic reactions. Therefore, it should only be performed under the supervision of a trained healthcare professional.

Tau proteins are a type of microtubule-associated protein (MAP) found primarily in neurons of the central nervous system. They play a crucial role in maintaining the stability and structure of microtubules, which are essential components of the cell's cytoskeleton. Tau proteins bind to and stabilize microtubules, helping to regulate their assembly and disassembly.

In Alzheimer's disease and other neurodegenerative disorders known as tauopathies, tau proteins can become abnormally hyperphosphorylated, leading to the formation of insoluble aggregates called neurofibrillary tangles (NFTs) within neurons. These aggregates disrupt the normal function of microtubules and contribute to the degeneration and death of nerve cells, ultimately leading to cognitive decline and other symptoms associated with these disorders.

Neuroblastoma is defined as a type of cancer that develops from immature nerve cells found in the fetal or early postnatal period, called neuroblasts. It typically occurs in infants and young children, with around 90% of cases diagnosed before age five. The tumors often originate in the adrenal glands but can also arise in the neck, chest, abdomen, or spine. Neuroblastoma is characterized by its ability to spread (metastasize) to other parts of the body, including bones, bone marrow, lymph nodes, and skin. The severity and prognosis of neuroblastoma can vary widely, depending on factors such as the patient's age at diagnosis, stage of the disease, and specific genetic features of the tumor.

The hippocampus is a complex, curved formation in the brain that resembles a seahorse (hence its name, from the Greek word "hippos" meaning horse and "kampos" meaning sea monster). It's part of the limbic system and plays crucial roles in the formation of memories, particularly long-term ones.

This region is involved in spatial navigation and cognitive maps, allowing us to recognize locations and remember how to get to them. Additionally, it's one of the first areas affected by Alzheimer's disease, which often results in memory loss as an early symptom.

Anatomically, it consists of two main parts: the Ammon's horn (or cornu ammonis) and the dentate gyrus. These structures are made up of distinct types of neurons that contribute to different aspects of learning and memory.

Alpha-synuclein is a protein that is primarily found in neurons (nerve cells) in the brain. It is encoded by the SNCA gene and is abundantly expressed in presynaptic terminals, where it is believed to play a role in the regulation of neurotransmitter release.

In certain neurological disorders, including Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy, alpha-synuclein can form aggregates known as Lewy bodies and Lewy neurites. These aggregates are a pathological hallmark of these diseases and are believed to contribute to the death of nerve cells, leading to the symptoms associated with these disorders.

The precise function of alpha-synuclein is not fully understood, but it is thought to be involved in various cellular processes such as maintaining the structure of the presynaptic terminal, regulating synaptic vesicle trafficking and neurotransmitter release, and protecting neurons from stress.

Amyloid plaque is a pathological hallmark of several degenerative diseases, including Alzheimer's disease. It refers to extracellular deposits of misfolded proteins that accumulate in various tissues and organs, but are most commonly found in the brain. The main component of these plaques is an abnormally folded form of a protein called amyloid-beta (Aβ). This protein is produced through the normal processing of the amyloid precursor protein (APP), but in amyloid plaques, it aggregates into insoluble fibrils that form the core of the plaque.

The accumulation of amyloid plaques is thought to contribute to neurodegeneration and cognitive decline in Alzheimer's disease and other related disorders. The exact mechanisms by which this occurs are not fully understood, but it is believed that the aggregation of Aβ into plaques leads to the disruption of neuronal function and viability, as well as the activation of inflammatory responses that can further damage brain tissue.

It's important to note that while amyloid plaques are a key feature of Alzheimer's disease, they are not exclusive to this condition. Amyloid plaques have also been found in other neurodegenerative disorders, as well as in some normal aging brains, although their significance in these contexts is less clear.

Microtubules are hollow, cylindrical structures composed of tubulin proteins in the cytoskeleton of eukaryotic cells. They play crucial roles in various cellular processes such as maintaining cell shape, intracellular transport, and cell division (mitosis and meiosis). Microtubules are dynamic, undergoing continuous assembly and disassembly, which allows them to rapidly reorganize in response to cellular needs. They also form part of important cellular structures like centrioles, basal bodies, and cilia/flagella.

Tubulin is a type of protein that forms microtubules, which are hollow cylindrical structures involved in the cell's cytoskeleton. These structures play important roles in various cellular processes, including maintaining cell shape, cell division, and intracellular transport. There are two main types of tubulin proteins: alpha-tubulin and beta-tubulin. They polymerize to form heterodimers, which then assemble into microtubules. The assembly and disassembly of microtubules are dynamic processes that are regulated by various factors, including GTP hydrolysis, motor proteins, and microtubule-associated proteins (MAPs). Tubulin is an essential component of the eukaryotic cell and has been a target for anti-cancer drugs such as taxanes and vinca alkaloids.

Alzheimer's disease is a progressive disorder that causes brain cells to waste away (degenerate) and die. It's the most common cause of dementia — a continuous decline in thinking, behavioral and social skills that disrupts a person's ability to function independently.

The early signs of the disease include forgetting recent events or conversations. As the disease progresses, a person with Alzheimer's disease will develop severe memory impairment and lose the ability to carry out everyday tasks.

Currently, there's no cure for Alzheimer's disease. However, treatments can temporarily slow the worsening of dementia symptoms and improve quality of life.

Cell differentiation is the process by which a less specialized cell, or stem cell, becomes a more specialized cell type with specific functions and structures. This process involves changes in gene expression, which are regulated by various intracellular signaling pathways and transcription factors. Differentiation results in the development of distinct cell types that make up tissues and organs in multicellular organisms. It is a crucial aspect of embryonic development, tissue repair, and maintenance of homeostasis in the body.

Neurofilament proteins (NFs) are type IV intermediate filament proteins that are specific to neurons. They are the major structural components of the neuronal cytoskeleton and play crucial roles in maintaining the structural integrity, stability, and diameter of axons. Neurofilaments are composed of three subunits: light (NFL), medium (NFM), and heavy (NFH) neurofilament proteins, which differ in their molecular weights. These subunits assemble into heteropolymers to form the neurofilament core, while the C-terminal tails of NFH and NFM extend outward from the core, interacting with other cellular components and participating in various neuronal functions. Increased levels of neurofilament proteins, particularly NFL, in cerebrospinal fluid (CSF) and blood are considered biomarkers for axonal damage and neurodegeneration in several neurological disorders, such as Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis (ALS), and multiple sclerosis (MS).

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.

Cell adhesion molecules (CAMs) are a type of protein that mediates the attachment or binding of cells to their surrounding extracellular matrix or to other cells. Neuronal cell adhesion molecules (NCAMs) are a specific subtype of CAMs that are primarily expressed on neurons and play crucial roles in the development, maintenance, and function of the nervous system.

NCAMs are involved in various processes such as cell recognition, migration, differentiation, synaptic plasticity, and neural circuit formation. They can interact with other NCAMs or other types of CAMs to form homophilic or heterophilic bonds, respectively. The binding of NCAMs can activate intracellular signaling pathways that regulate various cellular responses.

NCAMs are classified into three major families based on their molecular structure: the immunoglobulin superfamily (Ig-CAMs), the cadherin family, and the integrin family. The Ig-CAMs include NCAM1 (also known as CD56), which is a glycoprotein with multiple extracellular Ig-like domains and intracellular signaling motifs. The cadherin family includes N-cadherin, which mediates calcium-dependent cell-cell adhesion. The integrin family includes integrins such as α5β1 and αVβ3, which mediate cell-matrix adhesion.

Abnormalities in NCAMs have been implicated in various neurological disorders, including schizophrenia, Alzheimer's disease, and autism spectrum disorder. Therefore, understanding the structure and function of NCAMs is essential for developing therapeutic strategies to treat these conditions.

Phase-contrast microscopy is a type of optical microscopy that allows visualization of transparent or translucent specimens, such as living cells and their organelles, by increasing the contrast between areas with different refractive indices within the sample. This technique works by converting phase shifts in light passing through the sample into changes in amplitude, which can then be observed as differences in brightness and contrast.

In a phase-contrast microscope, a special condenser and objective are used to create an optical path difference between the direct and diffracted light rays coming from the specimen. The condenser introduces a phase shift for the diffracted light, while the objective contains a phase ring that compensates for this shift in the direct light. This results in the direct light appearing brighter than the diffracted light, creating contrast between areas with different refractive indices within the sample.

Phase-contrast microscopy is particularly useful for observing unstained living cells and their dynamic processes, such as cell division, motility, and secretion, without the need for stains or dyes that might affect their viability or behavior.

Laminin is a family of proteins that are an essential component of the basement membrane, which is a specialized type of extracellular matrix. Laminins are large trimeric molecules composed of three different chains: α, β, and γ. There are five different α chains, three different β chains, and three different γ chains that can combine to form at least 15 different laminin isoforms.

Laminins play a crucial role in maintaining the structure and integrity of basement membranes by interacting with other components of the extracellular matrix, such as collagen IV, and cell surface receptors, such as integrins. They are involved in various biological processes, including cell adhesion, differentiation, migration, and survival.

Laminin dysfunction has been implicated in several human diseases, including cancer, diabetic nephropathy, and muscular dystrophy.

The brain is the central organ of the nervous system, responsible for receiving and processing sensory information, regulating vital functions, and controlling behavior, movement, and cognition. It is divided into several distinct regions, each with specific functions:

1. Cerebrum: The largest part of the brain, responsible for higher cognitive functions such as thinking, learning, memory, language, and perception. It is divided into two hemispheres, each controlling the opposite side of the body.
2. Cerebellum: Located at the back of the brain, it is responsible for coordinating muscle movements, maintaining balance, and fine-tuning motor skills.
3. Brainstem: Connects the cerebrum and cerebellum to the spinal cord, controlling vital functions such as breathing, heart rate, and blood pressure. It also serves as a relay center for sensory information and motor commands between the brain and the rest of the body.
4. Diencephalon: A region that includes the thalamus (a major sensory relay station) and hypothalamus (regulates hormones, temperature, hunger, thirst, and sleep).
5. Limbic system: A group of structures involved in emotional processing, memory formation, and motivation, including the hippocampus, amygdala, and cingulate gyrus.

The brain is composed of billions of interconnected neurons that communicate through electrical and chemical signals. It is protected by the skull and surrounded by three layers of membranes called meninges, as well as cerebrospinal fluid that provides cushioning and nutrients.

Axonal transport is the controlled movement of materials and organelles within axons, which are the nerve fibers of neurons (nerve cells). This intracellular transport system is essential for maintaining the structural and functional integrity of axons, particularly in neurons with long axonal processes. There are two types of axonal transport: anterograde transport, which moves materials from the cell body toward the synaptic terminals, and retrograde transport, which transports materials from the synaptic terminals back to the cell body. Anterograde transport is typically slower than retrograde transport and can be divided into fast and slow components based on velocity. Fast anterograde transport moves vesicles containing neurotransmitters and their receptors, as well as mitochondria and other organelles, at speeds of up to 400 mm/day. Slow anterograde transport moves cytoskeletal elements, proteins, and RNA at speeds of 1-10 mm/day. Retrograde transport is primarily responsible for recycling membrane components, removing damaged organelles, and transmitting signals from the axon terminal to the cell body. Dysfunctions in axonal transport have been implicated in various neurodegenerative disorders, such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis (ALS).

The spiral ganglion is a structure located in the inner ear, specifically within the cochlea. It consists of nerve cell bodies that form the sensory component of the auditory nervous system. The spiral ganglion's neurons are bipolar and have peripheral processes that form synapses with hair cells in the organ of Corti, which is responsible for converting sound vibrations into electrical signals.

The central processes of these neurons then coalesce to form the cochlear nerve, which transmits these electrical signals to the brainstem and ultimately to the auditory cortex for processing and interpretation as sound. Damage to the spiral ganglion or its associated neural structures can lead to hearing loss or deafness.

Schwann cells, also known as neurolemmocytes, are a type of glial cell that form the myelin sheath around peripheral nervous system (PNS) axons, allowing for the rapid and efficient transmission of nerve impulses. These cells play a crucial role in the maintenance and function of the PNS.

Schwann cells originate from the neural crest during embryonic development and migrate to the developing nerves. They wrap around the axons in a spiral fashion, forming multiple layers of myelin, which insulates the nerve fibers and increases the speed of electrical impulse transmission. Each Schwann cell is responsible for myelinating a single segment of an axon, with the gaps between these segments called nodes of Ranvier.

Schwann cells also provide structural support to the neurons and contribute to the regeneration of injured peripheral nerves by helping to guide the regrowth of axons to their targets. Additionally, Schwann cells can participate in immune responses within the PNS, such as releasing cytokines and chemokines to recruit immune cells during injury or infection.

Medical Definition:
Microtubule-associated proteins (MAPs) are a diverse group of proteins that bind to microtubules, which are key components of the cytoskeleton in eukaryotic cells. MAPs play crucial roles in regulating microtubule dynamics and stability, as well as in mediating interactions between microtubules and other cellular structures. They can be classified into several categories based on their functions, including:

1. Microtubule stabilizers: These MAPs promote the assembly of microtubules and protect them from disassembly by enhancing their stability. Examples include tau proteins and MAP2.
2. Microtubule dynamics regulators: These MAPs modulate the rate of microtubule polymerization and depolymerization, allowing for dynamic reorganization of the cytoskeleton during cell division and other processes. Examples include stathmin and XMAP215.
3. Microtubule motor proteins: These MAPs use energy from ATP hydrolysis to move along microtubules, transporting various cargoes within the cell. Examples include kinesin and dynein.
4. Adapter proteins: These MAPs facilitate interactions between microtubules and other cellular structures, such as membranes, organelles, or signaling molecules. Examples include MAP4 and CLASPs.

Dysregulation of MAPs has been implicated in several diseases, including neurodegenerative disorders like Alzheimer's disease (where tau proteins form abnormal aggregates called neurofibrillary tangles) and cancer (where altered microtubule dynamics can contribute to uncontrolled cell division).

Nerve degeneration, also known as neurodegeneration, is the progressive loss of structure and function of neurons, which can lead to cognitive decline, motor impairment, and various other symptoms. This process occurs due to a variety of factors, including genetics, environmental influences, and aging. It is a key feature in several neurological disorders such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and multiple sclerosis. The degeneration can affect any part of the nervous system, leading to different symptoms depending on the location and extent of the damage.

Dendrites are the branched projections of a neuron that receive and process signals from other neurons. They are typically short and highly branching, increasing the surface area for receiving incoming signals. Dendrites are covered in small protrusions called dendritic spines, which can form connections with the axon terminals of other neurons through chemical synapses. The structure and function of dendrites play a critical role in the integration and processing of information in the nervous system.

Synucleins are a family of small, heat-stable, water-soluble proteins that are primarily expressed in neurons. They are involved in various cellular processes such as modulating synaptic plasticity, vesicle trafficking, and neurotransmitter release. The most well-known members of this family are alpha-synuclein, beta-synuclein, and gamma-synuclein.

Abnormal accumulation and aggregation of alpha-synuclein into insoluble fibrils called Lewy bodies and Lewy neurites are hallmark features of several neurodegenerative disorders, including Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy. These conditions are collectively referred to as synucleinopathies. The dysfunction and aggregation of alpha-synuclein are thought to contribute to the progressive loss of dopaminergic neurons in the substantia nigra pars compacta, a region of the brain involved in motor control, leading to the characteristic symptoms observed in these disorders.

Afferent neurons, also known as sensory neurons, are a type of nerve cell that conducts impulses or signals from peripheral receptors towards the central nervous system (CNS), which includes the brain and spinal cord. These neurons are responsible for transmitting sensory information such as touch, temperature, pain, sound, and light to the CNS for processing and interpretation. Afferent neurons have specialized receptor endings that detect changes in the environment and convert them into electrical signals, which are then transmitted to the CNS via synapses with other neurons. Once the signals reach the CNS, they are processed and integrated with other information to produce a response or reaction to the stimulus.

The retina is the innermost, light-sensitive layer of tissue in the eye of many vertebrates and some cephalopods. It receives light that has been focused by the cornea and lens, converts it into neural signals, and sends these to the brain via the optic nerve. The retina contains several types of photoreceptor cells including rods (which handle vision in low light) and cones (which are active in bright light and are capable of color vision).

In medical terms, any pathological changes or diseases affecting the retinal structure and function can lead to visual impairment or blindness. Examples include age-related macular degeneration, diabetic retinopathy, retinal detachment, and retinitis pigmentosa among others.

A synapse is a structure in the nervous system that allows for the transmission of signals from one neuron (nerve cell) to another. It is the point where the axon terminal of one neuron meets the dendrite or cell body of another, and it is here that neurotransmitters are released and received. The synapse includes both the presynaptic and postsynaptic elements, as well as the cleft between them.

At the presynaptic side, an action potential travels down the axon and triggers the release of neurotransmitters into the synaptic cleft through exocytosis. These neurotransmitters then bind to receptors on the postsynaptic side, which can either excite or inhibit the receiving neuron. The strength of the signal between two neurons is determined by the number and efficiency of these synapses.

Synapses play a crucial role in the functioning of the nervous system, allowing for the integration and processing of information from various sources. They are also dynamic structures that can undergo changes in response to experience or injury, which has important implications for learning, memory, and recovery from neurological disorders.

GAP-43 protein, also known as growth-associated protein 43 or B-50, is a neuronal protein that is highly expressed during development and axonal regeneration. It is involved in the regulation of synaptic plasticity, nerve impulse transmission, and neurite outgrowth. GAP-43 is localized to the growth cones of growing axons and is thought to play a role in the guidance and navigation of axonal growth during development and regeneration. It is a member of the calcium/calmodulin-dependent protein kinase substrate family and undergoes phosphorylation by several protein kinases, including PKC (protein kinase C), which regulates its function. GAP-43 has been implicated in various neurological disorders, such as Alzheimer's disease, Parkinson's disease, and schizophrenia.

The Amyloid Beta-Protein Precursor (AβPP) is a type of transmembrane protein that is widely expressed in various tissues and organs, including the brain. It plays a crucial role in normal physiological processes, such as neuronal development, synaptic plasticity, and repair.

AβPP undergoes proteolytic processing by enzymes called secretases, resulting in the production of several protein fragments, including the amyloid-beta (Aβ) peptide. Aβ is a small peptide that can aggregate and form insoluble fibrils, which are the main component of amyloid plaques found in the brains of patients with Alzheimer's disease (AD).

The accumulation of Aβ plaques is believed to contribute to the neurodegeneration and cognitive decline observed in AD. Therefore, AβPP and its proteolytic processing have been the focus of extensive research aimed at understanding the pathogenesis of AD and developing potential therapies.

The Fluorescent Antibody Technique (FAT) is a type of immunofluorescence assay used in laboratory medicine and pathology for the detection and localization of specific antigens or antibodies in tissues, cells, or microorganisms. In this technique, a fluorescein-labeled antibody is used to selectively bind to the target antigen or antibody, forming an immune complex. When excited by light of a specific wavelength, the fluorescein label emits light at a longer wavelength, typically visualized as green fluorescence under a fluorescence microscope.

The FAT is widely used in diagnostic microbiology for the identification and characterization of various bacteria, viruses, fungi, and parasites. It has also been applied in the diagnosis of autoimmune diseases and certain cancers by detecting specific antibodies or antigens in patient samples. The main advantage of FAT is its high sensitivity and specificity, allowing for accurate detection and differentiation of various pathogens and disease markers. However, it requires specialized equipment and trained personnel to perform and interpret the results.

The cytoskeleton is a complex network of various protein filaments that provides structural support, shape, and stability to the cell. It plays a crucial role in maintaining cellular integrity, intracellular organization, and enabling cell movement. The cytoskeleton is composed of three major types of protein fibers: microfilaments (actin filaments), intermediate filaments, and microtubules. These filaments work together to provide mechanical support, participate in cell division, intracellular transport, and help maintain the cell's architecture. The dynamic nature of the cytoskeleton allows cells to adapt to changing environmental conditions and respond to various stimuli.

Parasympathetic ganglia are collections of neurons located outside the central nervous system (CNS) that serve as relay stations for parasympathetic nerve impulses. The parasympathetic nervous system is one of the two subdivisions of the autonomic nervous system, which controls involuntary physiological responses.

The parasympathetic ganglia receive preganglionic fibers from the brainstem and sacral regions of the spinal cord. After synapsing in these ganglia, postganglionic fibers innervate target organs such as the heart, glands, and smooth muscles. The primary function of the parasympathetic nervous system is to promote rest, digestion, and energy conservation.

Parasympathetic ganglia are typically located close to or within the target organs they innervate. Examples include:

1. Ciliary ganglion: Innervates the ciliary muscle and iris sphincter in the eye, controlling accommodation and pupil constriction.
2. Pterygopalatine (sphenopalatine) ganglion: Supplies the lacrimal gland, mucous membranes of the nasal cavity, and palate, regulating tear production and nasal secretions.
3. Otic ganglion: Innervates the parotid gland, controlling salivary secretion.
4. Submandibular ganglion: Supplies the submandibular and sublingual salivary glands, regulating salivation.
5. Sacral parasympathetic ganglia: Located in the sacrum, they innervate the distal colon, rectum, and genitourinary organs, controlling defecation, urination, and sexual arousal.

These parasympathetic ganglia play crucial roles in maintaining homeostasis by regulating various bodily functions during rest and relaxation.

Electron microscopy (EM) is a type of microscopy that uses a beam of electrons to create an image of the sample being examined, resulting in much higher magnification and resolution than light microscopy. There are several types of electron microscopy, including transmission electron microscopy (TEM), scanning electron microscopy (SEM), and reflection electron microscopy (REM).

In TEM, a beam of electrons is transmitted through a thin slice of the sample, and the electrons that pass through the sample are focused to form an image. This technique can provide detailed information about the internal structure of cells, viruses, and other biological specimens, as well as the composition and structure of materials at the atomic level.

In SEM, a beam of electrons is scanned across the surface of the sample, and the electrons that are scattered back from the surface are detected to create an image. This technique can provide information about the topography and composition of surfaces, as well as the structure of materials at the microscopic level.

REM is a variation of SEM in which the beam of electrons is reflected off the surface of the sample, rather than scattered back from it. This technique can provide information about the surface chemistry and composition of materials.

Electron microscopy has a wide range of applications in biology, medicine, and materials science, including the study of cellular structure and function, disease diagnosis, and the development of new materials and technologies.

The spinal cord is a major part of the nervous system, extending from the brainstem and continuing down to the lower back. It is a slender, tubular bundle of nerve fibers (axons) and support cells (glial cells) that carries signals between the brain and the rest of the body. The spinal cord primarily serves as a conduit for motor information, which travels from the brain to the muscles, and sensory information, which travels from the body to the brain. It also contains neurons that can independently process and respond to information within the spinal cord without direct input from the brain.

The spinal cord is protected by the bony vertebral column (spine) and is divided into 31 segments: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal. Each segment corresponds to a specific region of the body and gives rise to pairs of spinal nerves that exit through the intervertebral foramina at each level.

The spinal cord is responsible for several vital functions, including:

1. Reflexes: Simple reflex actions, such as the withdrawal reflex when touching a hot surface, are mediated by the spinal cord without involving the brain.
2. Muscle control: The spinal cord carries motor signals from the brain to the muscles, enabling voluntary movement and muscle tone regulation.
3. Sensory perception: The spinal cord transmits sensory information, such as touch, temperature, pain, and vibration, from the body to the brain for processing and awareness.
4. Autonomic functions: The sympathetic and parasympathetic divisions of the autonomic nervous system originate in the thoracolumbar and sacral regions of the spinal cord, respectively, controlling involuntary physiological responses like heart rate, blood pressure, digestion, and respiration.

Damage to the spinal cord can result in various degrees of paralysis or loss of sensation below the level of injury, depending on the severity and location of the damage.

Contactin 2 is a gene that encodes for a protein involved in the nervous system. It belongs to the immunoglobulin superfamily and is a transmembrane protein that is primarily expressed in the brain. Contactin 2 plays a crucial role in the formation and maintenance of neural connections, also known as synapses.

The Contactin 2 protein is located on the surface of neurons and interacts with other proteins to help form and stabilize synapses. It is also involved in the development and function of the cerebellum, a part of the brain that controls motor coordination and balance. Mutations in the Contactin 2 gene have been associated with several neurological disorders, including epilepsy, intellectual disability, and autism spectrum disorder.

Nocodazole is not a medical condition or disease, but rather a pharmacological agent used in medical research and clinical settings. It's a synthetic chemical compound that belongs to the class of drugs known as microtubule inhibitors. Nocodazole works by binding to and disrupting the dynamic assembly and disassembly of microtubules, which are important components of the cell's cytoskeleton and play a critical role in cell division.

Nocodazole is primarily used in research settings as a tool for studying cell biology and mitosis, the process by which cells divide. It can be used to synchronize cells in the cell cycle or to induce mitotic arrest, making it useful for investigating various aspects of cell division and chromosome behavior.

In clinical settings, nocodazole has been used off-label as a component of some cancer treatment regimens, particularly in combination with other chemotherapeutic agents. Its ability to disrupt microtubules can interfere with the proliferation of cancer cells and enhance the effectiveness of certain anti-cancer drugs. However, its use is not widespread due to potential side effects and the availability of alternative treatments.

Adrenal gland neoplasms refer to abnormal growths or tumors in the adrenal glands. These glands are located on top of each kidney and are responsible for producing hormones that regulate various bodily functions such as metabolism, blood pressure, and stress response. Adrenal gland neoplasms can be benign (non-cancerous) or malignant (cancerous).

Benign adrenal tumors are called adenomas and are usually small and asymptomatic. However, some adenomas may produce excessive amounts of hormones, leading to symptoms such as high blood pressure, weight gain, and mood changes.

Malignant adrenal tumors are called adrenocortical carcinomas and are rare but aggressive cancers that can spread to other parts of the body. Symptoms of adrenocortical carcinoma may include abdominal pain, weight loss, and hormonal imbalances.

It is important to diagnose and treat adrenal gland neoplasms early to prevent complications and improve outcomes. Diagnostic tests may include imaging studies such as CT scans or MRIs, as well as hormone level testing and biopsy. Treatment options may include surgery, radiation therapy, chemotherapy, or a combination of these approaches.

The cerebral cortex is the outermost layer of the brain, characterized by its intricate folded structure and wrinkled appearance. It is a region of great importance as it plays a key role in higher cognitive functions such as perception, consciousness, thought, memory, language, and attention. The cerebral cortex is divided into two hemispheres, each containing four lobes: the frontal, parietal, temporal, and occipital lobes. These areas are responsible for different functions, with some regions specializing in sensory processing while others are involved in motor control or associative functions. The cerebral cortex is composed of gray matter, which contains neuronal cell bodies, and is covered by a layer of white matter that consists mainly of myelinated nerve fibers.

Amyloid beta-peptides (Aβ) are small protein fragments that are crucially involved in the pathogenesis of Alzheimer's disease. They are derived from a larger transmembrane protein called the amyloid precursor protein (APP) through a series of proteolytic cleavage events.

The two primary forms of Aβ peptides are Aβ40 and Aβ42, which differ in length by two amino acids. While both forms can be harmful, Aβ42 is more prone to aggregation and is considered to be the more pathogenic form. These peptides have the tendency to misfold and accumulate into oligomers, fibrils, and eventually insoluble plaques that deposit in various areas of the brain, most notably the cerebral cortex and hippocampus.

The accumulation of Aβ peptides is believed to initiate a cascade of events leading to neuroinflammation, oxidative stress, synaptic dysfunction, and neuronal death, which are all hallmarks of Alzheimer's disease. Although the exact role of Aβ in the onset and progression of Alzheimer's is still under investigation, it is widely accepted that they play a central part in the development of this debilitating neurodegenerative disorder.

'Aplysia' is a genus of marine mollusks belonging to the family Aplysiidae, also known as sea hares. These are large, slow-moving herbivores that inhabit temperate and tropical coastal waters worldwide. They have a unique appearance with a soft, ear-like parapodia on either side of their body and a rhinophore at the front end, which they use to detect chemical cues in their environment.

One of the reasons 'Aplysia' is well-known in the medical and scientific community is because of its use as a model organism in neuroscience research. The simple nervous system of 'Aplysia' has made it an ideal subject for studying the basic principles of learning and memory at the cellular level.

In particular, the work of Nobel laureate Eric Kandel and his colleagues on 'Aplysia' helped to establish important concepts in synaptic plasticity, a key mechanism underlying learning and memory. By investigating how sensory stimulation can modify the strength of connections between neurons in 'Aplysia', researchers have gained valuable insights into the molecular and cellular mechanisms that underlie learning and memory processes in all animals, including humans.

Intermediate filaments (IFs) are a type of cytoskeletal filament found in the cytoplasm of eukaryotic cells, including animal cells. They are called "intermediate" because they are smaller in diameter than microfilaments and larger than microtubules, two other types of cytoskeletal structures.

Intermediate filaments are composed of fibrous proteins that form long, unbranched, and flexible filaments. These filaments provide structural support to the cell and help maintain its shape. They also play a role in cell-to-cell adhesion, intracellular transport, and protection against mechanical stress.

Intermediate filaments are classified into six types based on their protein composition: Type I (acidic keratins), Type II (neutral/basic keratins), Type III (vimentin, desmin, peripherin), Type IV (neurofilaments), Type V (lamins), and Type VI (nestin). Each type of intermediate filament has a specific function and is expressed in different cell types. For example, Type I and II keratins are found in epithelial cells, while vimentin is expressed in mesenchymal cells.

Overall, intermediate filaments play an essential role in maintaining the structural integrity of cells and tissues, and their dysfunction has been implicated in various human diseases, including cancer, neurodegenerative disorders, and genetic disorders.

Confocal microscopy is a powerful imaging technique used in medical and biological research to obtain high-resolution, contrast-rich images of thick samples. This super-resolution technology provides detailed visualization of cellular structures and processes at various depths within a specimen.

In confocal microscopy, a laser beam focused through a pinhole illuminates a small spot within the sample. The emitted fluorescence or reflected light from this spot is then collected by a detector, passing through a second pinhole that ensures only light from the focal plane reaches the detector. This process eliminates out-of-focus light, resulting in sharp images with improved contrast compared to conventional widefield microscopy.

By scanning the laser beam across the sample in a raster pattern and collecting fluorescence at each point, confocal microscopy generates optical sections of the specimen. These sections can be combined to create three-dimensional reconstructions, allowing researchers to study cellular architecture and interactions within complex tissues.

Confocal microscopy has numerous applications in medical research, including studying protein localization, tracking intracellular dynamics, analyzing cell morphology, and investigating disease mechanisms at the cellular level. Additionally, it is widely used in clinical settings for diagnostic purposes, such as analyzing skin lesions or detecting pathogens in patient samples.

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

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

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

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

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.

Adrenergic fibers are a type of nerve fiber that releases neurotransmitters known as catecholamines, such as norepinephrine (noradrenaline) and epinephrine (adrenaline). These neurotransmitters bind to adrenergic receptors in various target organs, including the heart, blood vessels, lungs, glands, and other tissues, and mediate the "fight or flight" response to stress.

Adrenergic fibers can be classified into two types based on their neurotransmitter content:

1. Noradrenergic fibers: These fibers release norepinephrine as their primary neurotransmitter and are widely distributed throughout the autonomic nervous system, including the sympathetic and some parasympathetic ganglia. They play a crucial role in regulating cardiovascular function, respiration, metabolism, and other physiological processes.
2. Adrenergic fibers with dual innervation: These fibers contain both norepinephrine and epinephrine as neurotransmitters and are primarily located in the adrenal medulla. They release epinephrine into the bloodstream, which acts on distant target organs to produce a more widespread and intense "fight or flight" response than norepinephrine alone.

Overall, adrenergic fibers play a critical role in maintaining homeostasis and responding to stress by modulating various physiological functions through the release of catecholamines.

"Newborn animals" refers to the very young offspring of animals that have recently been born. In medical terminology, newborns are often referred to as "neonates," and they are classified as such from birth until about 28 days of age. During this time period, newborn animals are particularly vulnerable and require close monitoring and care to ensure their survival and healthy development.

The specific needs of newborn animals can vary widely depending on the species, but generally, they require warmth, nutrition, hydration, and protection from harm. In many cases, newborns are unable to regulate their own body temperature or feed themselves, so they rely heavily on their mothers for care and support.

In medical settings, newborn animals may be examined and treated by veterinarians to ensure that they are healthy and receiving the care they need. This can include providing medical interventions such as feeding tubes, antibiotics, or other treatments as needed to address any health issues that arise. Overall, the care and support of newborn animals is an important aspect of animal medicine and conservation efforts.

A ganglion is a cluster of neuron cell bodies in the peripheral nervous system. Ganglia are typically associated with nerves and serve as sites for sensory processing, integration, and relay of information between the periphery and the central nervous system (CNS). The two main types of ganglia are sensory ganglia, which contain pseudounipolar neurons that transmit sensory information to the CNS, and autonomic ganglia, which contain multipolar neurons that control involuntary physiological functions.

Examples of sensory ganglia include dorsal root ganglia (DRG), which are associated with spinal nerves, and cranial nerve ganglia, such as the trigeminal ganglion. Autonomic ganglia can be further divided into sympathetic and parasympathetic ganglia, which regulate different aspects of the autonomic nervous system.

It's worth noting that in anatomy, "ganglion" refers to a group of nerve cell bodies, while in clinical contexts, "ganglion" is often used to describe a specific type of cystic structure that forms near joints or tendons, typically in the wrist or foot. These ganglia are not related to the peripheral nervous system's ganglia but rather are fluid-filled sacs that may cause discomfort or pain due to their size or location.

The Central Nervous System (CNS) is the part of the nervous system that consists of the brain and spinal cord. It is called the "central" system because it receives information from, and sends information to, the rest of the body through peripheral nerves, which make up the Peripheral Nervous System (PNS).

The CNS is responsible for processing sensory information, controlling motor functions, and regulating various autonomic processes like heart rate, respiration, and digestion. The brain, as the command center of the CNS, interprets sensory stimuli, formulates thoughts, and initiates actions. The spinal cord serves as a conduit for nerve impulses traveling to and from the brain and the rest of the body.

The CNS is protected by several structures, including the skull (which houses the brain) and the vertebral column (which surrounds and protects the spinal cord). Despite these protective measures, the CNS remains vulnerable to injury and disease, which can have severe consequences due to its crucial role in controlling essential bodily functions.

Coculture techniques refer to a type of experimental setup in which two or more different types of cells or organisms are grown and studied together in a shared culture medium. This method allows researchers to examine the interactions between different cell types or species under controlled conditions, and to study how these interactions may influence various biological processes such as growth, gene expression, metabolism, and signal transduction.

Coculture techniques can be used to investigate a wide range of biological phenomena, including the effects of host-microbe interactions on human health and disease, the impact of different cell types on tissue development and homeostasis, and the role of microbial communities in shaping ecosystems. These techniques can also be used to test the efficacy and safety of new drugs or therapies by examining their effects on cells grown in coculture with other relevant cell types.

There are several different ways to establish cocultures, depending on the specific research question and experimental goals. Some common methods include:

1. Mixed cultures: In this approach, two or more cell types are simply mixed together in a culture dish or flask and allowed to grow and interact freely.
2. Cell-layer cultures: Here, one cell type is grown on a porous membrane or other support structure, while the second cell type is grown on top of it, forming a layered coculture.
3. Conditioned media cultures: In this case, one cell type is grown to confluence and its culture medium is collected and then used to grow a second cell type. This allows the second cell type to be exposed to any factors secreted by the first cell type into the medium.
4. Microfluidic cocultures: These involve growing cells in microfabricated channels or chambers, which allow for precise control over the spatial arrangement and flow of nutrients, waste products, and signaling molecules between different cell types.

Overall, coculture techniques provide a powerful tool for studying complex biological systems and gaining insights into the mechanisms that underlie various physiological and pathological processes.

Sulfonium compounds are organosulfur molecules that contain a central sulfur atom bonded to three alkyl or aryl groups and have the general formula (R-S-R'-R'')+X-, where R, R', and R'' are organic groups and X is an anion. These compounds are widely used in chemical synthesis as phase-transfer catalysts, alkylating agents, and in the production of detergents, pharmaceuticals, and agrochemicals. Sulfonium compounds can also be found in some natural sources, such as certain antibiotics and marine toxins.

Cell polarity refers to the asymmetric distribution of membrane components, cytoskeleton, and organelles in a cell. This asymmetry is crucial for various cellular functions such as directed transport, cell division, and signal transduction. The plasma membrane of polarized cells exhibits distinct domains with unique protein and lipid compositions that define apical, basal, and lateral surfaces of the cell.

In epithelial cells, for example, the apical surface faces the lumen or external environment, while the basolateral surface interacts with other cells or the extracellular matrix. The establishment and maintenance of cell polarity are regulated by various factors including protein complexes, lipids, and small GTPases. Loss of cell polarity has been implicated in several diseases, including cancer and neurological disorders.

Pseudopodia are temporary projections or extensions of the cytoplasm in certain types of cells, such as white blood cells (leukocytes) and some amoebas. They are used for locomotion and engulfing particles or other cells through a process called phagocytosis.

In simpler terms, pseudopodia are like "false feet" that some cells use to move around and interact with their environment. The term comes from the Greek words "pseudes," meaning false, and "podos," meaning foot.

I apologize for the confusion, but "Bucladesine" is not a recognized medical term or a medication in current use in medicine. It's possible that there may be some mistake or typo in the spelling. If you have any more context about where you encountered this term, I might be able to provide a more accurate and helpful response.

Lewy body disease, also known as dementia with Lewy bodies, is a type of progressive degenerative dementia that affects thinking, behavior, and movement. It's named after Dr. Friedrich Lewy, the scientist who discovered the abnormal protein deposits, called Lewy bodies, that are characteristic of this disease.

Lewy bodies are made up of a protein called alpha-synuclein and are found in the brain cells of individuals with Lewy body disease. These abnormal protein deposits are also found in people with Parkinson's disease, but they are more widespread in Lewy body disease, affecting multiple areas of the brain.

The symptoms of Lewy body disease can vary from person to person, but they often include:

* Cognitive decline, such as memory loss, confusion, and difficulty with problem-solving
* Visual hallucinations and delusions
* Parkinsonian symptoms, such as stiffness, tremors, and difficulty walking or moving
* Fluctuations in alertness and attention
* REM sleep behavior disorder, where a person acts out their dreams during sleep

Lewy body disease is a progressive condition, which means that the symptoms get worse over time. Currently, there is no cure for Lewy body disease, but medications can help manage some of the symptoms.

Cell communication, also known as cell signaling, is the process by which cells exchange and transmit signals between each other and their environment. This complex system allows cells to coordinate their functions and maintain tissue homeostasis. Cell communication can occur through various mechanisms including:

1. Autocrine signaling: When a cell releases a signal that binds to receptors on the same cell, leading to changes in its behavior or function.
2. Paracrine signaling: When a cell releases a signal that binds to receptors on nearby cells, influencing their behavior or function.
3. Endocrine signaling: When a cell releases a hormone into the bloodstream, which then travels to distant target cells and binds to specific receptors, triggering a response.
4. Synaptic signaling: In neurons, communication occurs through the release of neurotransmitters that cross the synapse and bind to receptors on the postsynaptic cell, transmitting electrical or chemical signals.
5. Contact-dependent signaling: When cells physically interact with each other, allowing for the direct exchange of signals and information.

Cell communication is essential for various physiological processes such as growth, development, differentiation, metabolism, immune response, and tissue repair. Dysregulation in cell communication can contribute to diseases, including cancer, diabetes, and neurological disorders.

Culture techniques are methods used in microbiology to grow and multiply microorganisms, such as bacteria, fungi, or viruses, in a controlled laboratory environment. These techniques allow for the isolation, identification, and study of specific microorganisms, which is essential for diagnostic purposes, research, and development of medical treatments.

The most common culture technique involves inoculating a sterile growth medium with a sample suspected to contain microorganisms. The growth medium can be solid or liquid and contains nutrients that support the growth of the microorganisms. Common solid growth media include agar plates, while liquid growth media are used for broth cultures.

Once inoculated, the growth medium is incubated at a temperature that favors the growth of the microorganisms being studied. During incubation, the microorganisms multiply and form visible colonies on the solid growth medium or turbid growth in the liquid growth medium. The size, shape, color, and other characteristics of the colonies can provide important clues about the identity of the microorganism.

Other culture techniques include selective and differential media, which are designed to inhibit the growth of certain types of microorganisms while promoting the growth of others, allowing for the isolation and identification of specific pathogens. Enrichment cultures involve adding specific nutrients or factors to a sample to promote the growth of a particular type of microorganism.

Overall, culture techniques are essential tools in microbiology and play a critical role in medical diagnostics, research, and public health.

Axotomy is a medical term that refers to the surgical cutting or severing of an axon, which is the long, slender projection of a neuron (nerve cell) that conducts electrical impulses away from the cell body and toward other cells. Axons are a critical component of the nervous system, allowing for communication between different parts of the body.

Axotomy is often used in research settings to study the effects of axonal injury on neuronal function and regeneration. This procedure can provide valuable insights into the mechanisms underlying neurodegenerative disorders and potential therapies for nerve injuries. However, it is important to note that axotomy can also have significant consequences for the affected neuron, including changes in gene expression, metabolism, and overall survival.

Cytochalasins are a group of fungal metabolites that have the ability to disrupt the organization and dynamics of the cytoskeleton in eukaryotic cells. They bind to the barbed end of actin filaments, preventing the addition or loss of actin subunits, which results in the inhibition of actin polymerization and depolymerization. This can lead to changes in cell shape, motility, and cytokinesis (the process by which a cell divides into two daughter cells).

There are several different types of cytochalasins, including cytochalasin A, B, C, D, and E, among others. Each type has slightly different effects on the actin cytoskeleton and may also have other cellular targets. Cytochalasins have been widely used in research to study the role of the actin cytoskeleton in various cellular processes.

In addition to their use in research, cytochalasins have also been investigated for their potential therapeutic applications. For example, some studies have suggested that cytochalasins may have anti-cancer properties by inhibiting the proliferation and migration of cancer cells. However, more research is needed before these compounds can be developed into effective treatments for human diseases.

Actin is a type of protein that forms part of the contractile apparatus in muscle cells, and is also found in various other cell types. It is a globular protein that polymerizes to form long filaments, which are important for many cellular processes such as cell division, cell motility, and the maintenance of cell shape. In muscle cells, actin filaments interact with another type of protein called myosin to enable muscle contraction. Actins can be further divided into different subtypes, including alpha-actin, beta-actin, and gamma-actin, which have distinct functions and expression patterns in the body.

The geniculate ganglion is a sensory ganglion (a cluster of nerve cell bodies) located in the facial nerve (cranial nerve VII). It is responsible for the special sense of taste for the anterior two-thirds of the tongue and the sensation of skin over the external ear and parts of the face. The term "geniculate" means "knee-shaped," which describes the appearance of this part of the facial nerve.

The superior cervical ganglion is a part of the autonomic nervous system, specifically the sympathetic division. It is a collection of nerve cell bodies (ganglion) that are located in the neck region (cervical) and is formed by the fusion of several smaller ganglia.

This ganglion is responsible for providing innervation to various structures in the head and neck, including the eyes, scalp, face muscles, meninges (membranes surrounding the brain and spinal cord), and certain glands such as the salivary and sweat glands. It does this through the postganglionic fibers that branch off from the ganglion and synapse with target organs or tissues.

The superior cervical ganglion is an essential component of the autonomic nervous system, which controls involuntary physiological functions such as heart rate, blood pressure, digestion, and respiration.

Neurogenesis is the process by which new neurons (nerve cells) are generated in the brain. It occurs throughout life in certain areas of the brain, such as the hippocampus and subventricular zone, although the rate of neurogenesis decreases with age. Neurogenesis involves the proliferation, differentiation, and integration of new neurons into existing neural circuits. This process plays a crucial role in learning, memory, and recovery from brain injury or disease.

Protease nexins are a group of proteins that regulate the activity of proteases, which are enzymes that break down other proteins. Proteases play important roles in various biological processes, including blood clotting, immune response, and cell death. However, uncontrolled or excessive protease activity can lead to harmful effects, such as tissue damage and disease progression.

Protease nexins function by forming stable complexes with specific proteases, thereby inhibiting their activity. These complexes also serve as a reservoir of inactive proteases that can be rapidly activated when needed. Protease nexins are involved in various physiological and pathological processes, such as inflammation, neurodegeneration, and cancer.

One well-known example of a protease nexin is the tissue plasminogen activator (tPA) - neuroserpin complex. Neuroserpin is a serine protease inhibitor that forms a complex with tPA, an enzyme that plays a critical role in breaking down blood clots. By forming this complex, neuroserpin regulates the activity of tPA and prevents excessive fibrinolysis, which can lead to bleeding disorders. Mutations in the gene encoding neuroserpin have been associated with familial dementia with Lewy bodies, a form of neurodegenerative disorder.

Neuroanatomical tract-tracing techniques are a set of neuroanatomical methods used to map the connections and pathways between different neurons, neural nuclei, or brain regions. These techniques involve introducing a tracer substance into a specific population of neurons, which is then transported through the axons and dendrites to other connected cells. The distribution of the tracer can be visualized and analyzed to determine the pattern of connectivity between different brain areas.

There are two main types of neuroanatomical tract-tracing techniques: anterograde and retrograde. Anterograde tracing involves introducing a tracer into the cell body or dendrites of a neuron, which is then transported to the axon terminals in target areas. Retrograde tracing, on the other hand, involves introducing a tracer into the axon terminals of a neuron, which is then transported back to the cell body and dendrites.

Examples of neuroanatomical tract-tracing techniques include the use of horseradish peroxidase (HRP), fluorescent tracers, radioactive tracers, and viral vectors. These techniques have been instrumental in advancing our understanding of brain circuitry and function, and continue to be an important tool in neuroscience research.

The cerebellum is a part of the brain that lies behind the brainstem and is involved in the regulation of motor movements, balance, and coordination. It contains two hemispheres and a central portion called the vermis. The cerebellum receives input from sensory systems and other areas of the brain and spinal cord and sends output to motor areas of the brain. Damage to the cerebellum can result in problems with movement, balance, and coordination.

Retinal Ganglion Cells (RGCs) are a type of neuron located in the innermost layer of the retina, the light-sensitive tissue at the back of the eye. These cells receive visual information from photoreceptors (rods and cones) via intermediate cells called bipolar cells. RGCs then send this visual information through their long axons to form the optic nerve, which transmits the signals to the brain for processing and interpretation as vision.

There are several types of RGCs, each with distinct morphological and functional characteristics. Some RGCs are specialized in detecting specific features of the visual scene, such as motion, contrast, color, or brightness. The diversity of RGCs allows for a rich and complex representation of the visual world in the brain.

Damage to RGCs can lead to various visual impairments, including loss of vision, reduced visual acuity, and altered visual fields. Conditions associated with RGC damage or degeneration include glaucoma, optic neuritis, ischemic optic neuropathy, and some inherited retinal diseases.

Contactins are a family of glycosylphosphatidylinositol (GPI)-anchored neuronal cell adhesion molecules that play important roles in the nervous system. They are involved in the formation and maintenance of neural connections, including axon guidance, fasciculation, and synaptogenesis. Contactins have immunoglobulin-like domains and fibronectin type III repeats, which mediate their homophilic or heterophilic interactions with other molecules on the cell surface. There are six known members of the contactin family: contactin-1 (also known as F3), contactin-2 (TAG-1), contactin-3 (BIG-1), contactin-4 (BIG-2), contactin-5, and contactin-6. Mutations in some contactin genes have been associated with neurological disorders such as X-linked mental retardation and epilepsy.

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.

Cell enlargement is a process in which the size of a cell increases due to various reasons. This can occur through an increase in the amount of cytoplasm, organelles, or both within the cell. Cell enlargement can be a normal physiological response to stimuli such as growth and development, or it can be a pathological change associated with certain medical conditions.

There are several mechanisms by which cells can enlarge. One way is through the process of hypertrophy, in which individual cells increase in size due to an increase in the size of their component parts, such as organelles and cytoplasm. This type of cell enlargement is often seen in response to increased functional demands on the cell, such as in the case of muscle cells that enlarge in response to exercise.

Another mechanism by which cells can enlarge is through the process of hyperplasia, in which the number of cells in a tissue or organ increases due to an increase in the rate of cell division. While this does not result in individual cells becoming larger, it can lead to an overall increase in the size of the tissue or organ.

Cell enlargement can also occur as a result of abnormal accumulations of fluids or other materials within the cell. For example, cells may become enlarged due to the accumulation of lipids, glycogen, or other storage products, or due to the accumulation of waste products that are not properly cleared from the cell.

In some cases, cell enlargement can be a sign of a medical condition or disease process. For example, certain types of cancer cells may exhibit abnormal growth and enlargement, as can cells affected by certain genetic disorders or infections. In these cases, cell enlargement may be accompanied by other symptoms or signs that can help to diagnose the underlying condition.

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

Semaphorin-3A is a protein that belongs to the larger family of semaphorins, which are signaling molecules involved in various biological processes including axon guidance during neural development. Specifically, Semaphorin-3A is known as a chemorepellent, meaning it repels growing nerve cells (neurons) and regulates their migration, growth, and pathfinding. It plays crucial roles in the formation of the nervous system by controlling the navigation and fasciculation (the clustering together) of axons during development. Additionally, Semaphorin-3A has been implicated in immune responses and cancer progression, acting as a tumor suppressor or promoter depending on the context.

The sciatic nerve is the largest and longest nerve in the human body, running from the lower back through the buttocks and down the legs to the feet. It is formed by the union of the ventral rami (branches) of the L4 to S3 spinal nerves. The sciatic nerve provides motor and sensory innervation to various muscles and skin areas in the lower limbs, including the hamstrings, calf muscles, and the sole of the foot. Sciatic nerve disorders or injuries can result in symptoms such as pain, numbness, tingling, or weakness in the lower back, hips, legs, and feet, known as sciatica.

Motor neurons are specialized nerve cells in the brain and spinal cord that play a crucial role in controlling voluntary muscle movements. They transmit electrical signals from the brain to the muscles, enabling us to perform actions such as walking, talking, and swallowing. There are two types of motor neurons: upper motor neurons, which originate in the brain's motor cortex and travel down to the brainstem and spinal cord; and lower motor neurons, which extend from the brainstem and spinal cord to the muscles. Damage or degeneration of these motor neurons can lead to various neurological disorders, such as amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA).

Cell shape refers to the physical form or configuration of a cell, which is determined by the cytoskeleton (the internal framework of the cell) and the extracellular matrix (the external environment surrounding the cell). The shape of a cell can vary widely depending on its type and function. For example, some cells are spherical, such as red blood cells, while others are elongated or irregularly shaped. Changes in cell shape can be indicative of various physiological or pathological processes, including development, differentiation, migration, and disease.

Green Fluorescent Protein (GFP) is not a medical term per se, but a scientific term used in the field of molecular biology. GFP is a protein that exhibits bright green fluorescence when exposed to light, particularly blue or ultraviolet light. It was originally discovered in the jellyfish Aequorea victoria.

In medical and biological research, scientists often use recombinant DNA technology to introduce the gene for GFP into other organisms, including bacteria, plants, and animals, including humans. This allows them to track the expression and localization of specific genes or proteins of interest in living cells, tissues, or even whole organisms.

The ability to visualize specific cellular structures or processes in real-time has proven invaluable for a wide range of research areas, from studying the development and function of organs and organ systems to understanding the mechanisms of diseases and the effects of therapeutic interventions.

Ephrin-A5 is a type of protein that belongs to the ephrin family. Ephrins are membrane-bound proteins that interact with Eph receptors, which are tyrosine kinase receptors found on the surface of cells. The interaction between ephrins and Eph receptors plays a crucial role in the development and function of the nervous system, including axon guidance, cell migration, and synaptic plasticity.

Ephrin-A5 is specifically classified as a glycosylphosphatidylinositol (GPI)-anchored protein, which means it is attached to the outer layer of the cell membrane through a GPI anchor. It is primarily expressed in various tissues, including the brain, heart, and lungs.

In the nervous system, Ephrin-A5 and its receptor, EphA4, are involved in repulsive guidance cues that help to establish proper neuronal connections during development. Dysregulation of this interaction has been implicated in several neurological disorders, such as spinal cord injuries, Alzheimer's disease, and schizophrenia.

Inclusion bodies are abnormal, intracellular accumulations or aggregations of various misfolded proteins, protein complexes, or other materials within the cells of an organism. They can be found in various tissues and cell types and are often associated with several pathological conditions, including infectious diseases, neurodegenerative disorders, and genetic diseases.

Inclusion bodies can vary in size, shape, and location depending on the specific disease or condition. Some inclusion bodies have a characteristic appearance under the microscope, such as eosinophilic (pink) staining with hematoxylin and eosin (H&E) histological stain, while others may require specialized stains or immunohistochemical techniques to identify the specific misfolded proteins involved.

Examples of diseases associated with inclusion bodies include:

1. Infectious diseases: Some viral infections, such as HIV, hepatitis B and C, and herpes simplex virus, can lead to the formation of inclusion bodies within infected cells.
2. Neurodegenerative disorders: Several neurodegenerative diseases are characterized by the presence of inclusion bodies, including Alzheimer's disease (amyloid-beta plaques and tau tangles), Parkinson's disease (Lewy bodies), Huntington's disease (Huntingtin aggregates), and amyotrophic lateral sclerosis (TDP-43 and SOD1 inclusions).
3. Genetic diseases: Certain genetic disorders, such as Danon disease, neuronal intranuclear inclusion disease, and some lysosomal storage disorders, can also present with inclusion bodies due to the accumulation of abnormal proteins or metabolic products within cells.

The exact role of inclusion bodies in disease pathogenesis remains unclear; however, they are often associated with cellular dysfunction, oxidative stress, and increased inflammation, which can contribute to disease progression and neurodegeneration.

The nervous system is a complex, highly organized network of specialized cells called neurons and glial cells that communicate with each other via electrical and chemical signals to coordinate various functions and activities in the body. It consists of two main parts: the central nervous system (CNS), including the brain and spinal cord, and the peripheral nervous system (PNS), which includes all the nerves and ganglia outside the CNS.

The primary function of the nervous system is to receive, process, and integrate information from both internal and external environments and then respond by generating appropriate motor outputs or behaviors. This involves sensing various stimuli through specialized receptors, transmitting this information through afferent neurons to the CNS for processing, integrating this information with other inputs and memories, making decisions based on this processed information, and finally executing responses through efferent neurons that control effector organs such as muscles and glands.

The nervous system can be further divided into subsystems based on their functions, including the somatic nervous system, which controls voluntary movements and reflexes; the autonomic nervous system, which regulates involuntary physiological processes like heart rate, digestion, and respiration; and the enteric nervous system, which is a specialized subset of the autonomic nervous system that controls gut functions. Overall, the nervous system plays a critical role in maintaining homeostasis, regulating behavior, and enabling cognition and consciousness.

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

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

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

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

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

Protein transport, in the context of cellular biology, refers to the process by which proteins are actively moved from one location to another within or between cells. This is a crucial mechanism for maintaining proper cell function and regulation.

Intracellular protein transport involves the movement of proteins within a single cell. Proteins can be transported across membranes (such as the nuclear envelope, endoplasmic reticulum, Golgi apparatus, or plasma membrane) via specialized transport systems like vesicles and transport channels.

Intercellular protein transport refers to the movement of proteins from one cell to another, often facilitated by exocytosis (release of proteins in vesicles) and endocytosis (uptake of extracellular substances via membrane-bound vesicles). This is essential for communication between cells, immune response, and other physiological processes.

It's important to note that any disruption in protein transport can lead to various diseases, including neurological disorders, cancer, and metabolic conditions.

Transgenic mice are genetically modified rodents that have incorporated foreign DNA (exogenous DNA) into their own genome. This is typically done through the use of recombinant DNA technology, where a specific gene or genetic sequence of interest is isolated and then introduced into the mouse embryo. The resulting transgenic mice can then express the protein encoded by the foreign gene, allowing researchers to study its function in a living organism.

The process of creating transgenic mice usually involves microinjecting the exogenous DNA into the pronucleus of a fertilized egg, which is then implanted into a surrogate mother. The offspring that result from this procedure are screened for the presence of the foreign DNA, and those that carry the desired genetic modification are used to establish a transgenic mouse line.

Transgenic mice have been widely used in biomedical research to model human diseases, study gene function, and test new therapies. They provide a valuable tool for understanding complex biological processes and developing new treatments for a variety of medical conditions.

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

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

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

Nerve tissue, also known as neural tissue, is a type of specialized tissue that is responsible for the transmission of electrical signals and the processing of information in the body. It is a key component of the nervous system, which includes the brain, spinal cord, and peripheral nerves. Nerve tissue is composed of two main types of cells: neurons and glial cells.

Neurons are the primary functional units of nerve tissue. They are specialized cells that are capable of generating and transmitting electrical signals, known as action potentials. Neurons have a unique structure, with a cell body (also called the soma) that contains the nucleus and other organelles, and processes (dendrites and axons) that extend from the cell body and are used to receive and transmit signals.

Glial cells, also known as neuroglia or glia, are non-neuronal cells that provide support and protection for neurons. There are several different types of glial cells, including astrocytes, oligodendrocytes, microglia, and Schwann cells. These cells play a variety of roles in the nervous system, such as providing structural support, maintaining the proper environment for neurons, and helping to repair and regenerate nerve tissue after injury.

Nerve tissue is found throughout the body, but it is most highly concentrated in the brain and spinal cord, which make up the central nervous system (CNS). The peripheral nerves, which are the nerves that extend from the CNS to the rest of the body, also contain nerve tissue. Nerve tissue is responsible for transmitting sensory information from the body to the brain, controlling muscle movements, and regulating various bodily functions such as heart rate, digestion, and respiration.

A nerve crush injury is a type of peripheral nerve injury that occurs when there is excessive pressure or compression applied to a nerve, causing it to become damaged or dysfunctional. This can happen due to various reasons such as trauma from accidents, surgical errors, or prolonged pressure on the nerve from tight casts, clothing, or positions.

The compression disrupts the normal functioning of the nerve, leading to symptoms such as numbness, tingling, weakness, or pain in the affected area. In severe cases, a nerve crush injury can cause permanent damage to the nerve, leading to long-term disability or loss of function. Treatment for nerve crush injuries typically involves relieving the pressure on the nerve, providing supportive care, and in some cases, surgical intervention may be necessary to repair the damaged nerve.

Astrocytes are a type of star-shaped glial cell found in the central nervous system (CNS), including the brain and spinal cord. They play crucial roles in supporting and maintaining the health and function of neurons, which are the primary cells responsible for transmitting information in the CNS.

Some of the essential functions of astrocytes include:

1. Supporting neuronal structure and function: Astrocytes provide structural support to neurons by ensheathing them and maintaining the integrity of the blood-brain barrier, which helps regulate the entry and exit of substances into the CNS.
2. Regulating neurotransmitter levels: Astrocytes help control the levels of neurotransmitters in the synaptic cleft (the space between two neurons) by taking up excess neurotransmitters and breaking them down, thus preventing excessive or prolonged activation of neuronal receptors.
3. Providing nutrients to neurons: Astrocytes help supply energy metabolites, such as lactate, to neurons, which are essential for their survival and function.
4. Modulating synaptic activity: Through the release of various signaling molecules, astrocytes can modulate synaptic strength and plasticity, contributing to learning and memory processes.
5. Participating in immune responses: Astrocytes can respond to CNS injuries or infections by releasing pro-inflammatory cytokines and chemokines, which help recruit immune cells to the site of injury or infection.
6. Promoting neuronal survival and repair: In response to injury or disease, astrocytes can become reactive and undergo morphological changes that aid in forming a glial scar, which helps contain damage and promote tissue repair. Additionally, they release growth factors and other molecules that support the survival and regeneration of injured neurons.

Dysfunction or damage to astrocytes has been implicated in several neurological disorders, including Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis (ALS), and multiple sclerosis (MS).

In invertebrate biology, ganglia are clusters of neurons that function as a centralized nervous system. They can be considered as the equivalent to a vertebrate's spinal cord and brain. Ganglia serve to process sensory information, coordinate motor functions, and integrate various neural activities within an invertebrate organism.

Invertebrate ganglia are typically found in animals such as arthropods (insects, crustaceans), annelids (earthworms), mollusks (snails, squids), and cnidarians (jellyfish). The structure of the ganglia varies among different invertebrate groups.

For example, in arthropods, the central nervous system consists of a pair of connected ganglia called the supraesophageal ganglion or brain, and the subesophageal ganglion, located near the esophagus. The ventral nerve cord runs along the length of the body, containing pairs of ganglia that control specific regions of the body.

In mollusks, the central nervous system is composed of several ganglia, which can be fused or dispersed, depending on the species. In cephalopods (such as squids and octopuses), the brain is highly developed and consists of several lobes that perform various functions, including learning and memory.

Overall, invertebrate ganglia are essential components of the nervous system that allow these animals to respond to environmental stimuli, move, and interact with their surroundings.

Sometime between day 1.5 and day 3, one of the minor neurites begins to outgrow the other neurites significantly. This neurite ... E Meijering's article on the state of neurite detection NeuronJ neurite tracing program Synd synapse and neurite detection ... The developing neurite sums together all of these growth signals in order to determine which direction the neurite will ... 30% of the time, a neurite not destined to become the axon protrudes from the cell body first. 10% of the time, the neurite ...
... p-tau dot-like neurites. Purely astrocytic perivascular p-tau pathology represents ARTAG and does not meet the criteria for CTE ...
Ju, Yo-El; Janmey, Paul A.; McCormick, Margaret E.; Sawyer, Evelyn S.; Flanagan, Lisa A. (April 1, 2007). "Enhanced neurite ... Ju, Yo-El; Janmey, Paul A.; McCormick, Margaret E.; Sawyer, Evelyn S.; Flanagan, Lisa A. (April 1, 2007). "Enhanced neurite ... Flanagan, Lisa A.; Ju, Yo-El; Marg, Beatrice; Osterfield, Miriam; Janmey, Paul A. (December 20, 2002). "Neurite branching on ...
Neurites are thin extensions from a neuronal cell body, consisting of dendrites (specialized to receive synaptic inputs from ... These questions include how signals are processed by neurites and somas and how neurotransmitters and electrical signals are ... Flynn, Kevin C (July 2013). "The cytoskeleton and neurite initiation". BioArchitecture. 3 (4): 86-109. doi:10.4161/bioa.26259. ...
Neurites extend in all directions in thick bundles on the carbon fiber; however with the other three fibers, neurites extended ... developing neurites demonstrated contact guidance with features as small as 70 nm and greater than 90% of the neurites were ... there was less decrease as the range of angles over which the neurites emerged was increased. Also, the neurites were on ... the neurons on the stripe-patterned films had less neurites per cell and longer neurites compared to the neurons on non- ...
Lewy neurites, thread-like alpha-synuclein aggregates, are more prevalent than globular Lewy bodies in this stage. In addition ... Similar to Stage 1, Lewy neurites outnumber Lewy bodies. At the beginning of Stage 3, the disease has entered the substantia ...
2019) "Three-dimensional alteration of neurites in schizophrenia", Transl. Psychiatry 9, 85 DOI:10.1038/s41398-019-0427-4. ...
"Multiple transmitter systems contribute neurites to individual senile plaques". Journal of Neuropathology and Experimental ...
A mechanism for neurite outgrowth inhibition". The Journal of Biological Chemistry. 276 (23): 20280-5. doi:10.1074/jbc. ... The activation of the rho kinase pathway leads to the phosphorylation of proteins which inhibit neurite outgrowth. Myelin ... "Myelin-associated glycoprotein interacts with neurons via a sialic acid binding site at ARG118 and a distinct neurite ... "Identification of myelin-associated glycoprotein as a major myelin-derived inhibitor of neurite growth". Neuron. 13 (4): 805-11 ...
... , also known as Neurite outgrowth inhibitor or Nogo, is a protein that in humans is encoded by the RTN4 gene that ... The product of this gene is a potent neurite outgrowth inhibitor that may also help block the regeneration of the central ... July 2004). "The neurite outgrowth inhibitor Nogo A is involved in autoimmune-mediated demyelination". Nature Neuroscience. 7 ( ... Both amino-Nogo and Nogo-66 are involved in inhibitory responses, where amino-Nogo is a strong inhibitor of neurite outgrowth, ...
One of these neurites eventually becomes the axon and grows longer than the dendritic neurites. CRMP-2 helps facilitate the ... Extensions of early neurons called lamellipodia form the early neurites. The neurites are indistinguishable between dendrites ... involvement in axonal guidance has been proposed by localization of CRMPs in neurites and axonal growth cones. CRMPs ... of CRMP-2 in people with Alzheimer's disease promotes the expression of neurofibrillary tangles and plaque neurites which are ...
... "miR-375 inhibits differentiation of neurites by lowering HuD levels". Mol Cell Biol. 30 (17): 4197-4210. doi:10.1128/MCB.00316- ...
Abnormal neurites in amyloid plaques are tortuous, often swollen axons and dendrites. The neurites contain a variety of ... Abnormal neurites and activated glial cells are not typical of most diffuse plaques, and it has been suggested that diffuse ... Proteopathy Cras P; Kawai M; Lowery D; Gonzalez-DeWhitt P; Greenberg B; Perry G (September 1991). "Senile plaque neurites in ... Classical plaques also include abnormal, swollen neuronal processes (neurites) deriving from many different types of neurons, ...
... s promote neurite outgrowth and cell adhesion. The intracellular domain interacts with the DNA-binding transcriptional ...
Deister, C.; Schmidt, C. E. (2006). "Optimizing neurotrophic factor combinations for neurite outgrowth". Journal of Neural ...
Li ZY, Kljavin IJ, Milam AH (1995). "Rod photoreceptor neurite sprouting in retinitis pigmentosa". J. Neurosci. 15 (8): 5429-38 ...
Li ZY, Kljavin IJ, Milam AH (1995). "Rod photoreceptor neurite sprouting in retinitis pigmentosa". J. Neurosci. 15 (8): 5429-38 ...
Pearson AG, Gray CW, Pearson JF, Greenwood JM, During MJ, Dragunow M (December 2003). "ATF3 enhances c-Jun-mediated neurite ...
"Optimizing neurotrophic factor combinations for neurite outgrowth". Journal of Neural Engineering. 3 (2): 172-179. doi:10.1088/ ...
Pearson AG, Gray CW, Pearson JF, Greenwood JM, During MJ, Dragunow M (December 2003). "ATF3 enhances c-Jun-mediated neurite ...
Oral administration in AD mice models reduces degeneration of cholinergic neurites. Furthermore, by a direct activation of ... Recent studies demonstrated the neurotrophic activity of carvacrol by inducing neurite outgrowth and phosphorylation of TrkA in ... promoting neurite outgrowth in PC12 cells. Furthermore, the peptidomimetic cerebrolysin is known for its protective role in ... Reverses Cholinergic Neurite Dystrophy in Alzheimer's Disease Mouse Models with Mid- to Late-Stage Disease Progression". PLOS ...
"Oxidative stress reveals heterogeneity of FMRP granules in PC12 cell neurites". Brain Research. 1112 (1): 56-64. doi:10.1016/j. ...
Synapse formation and neurite growth are also impaired. A second group of researchers generated another neural specific ... Wiemerslage L, Lee D (March 2016). "Quantification of mitochondrial morphology in neurites of dopaminergic neurons using ...
The encoded protein appears to promote Neurite formation. A mutation in this gene has been reported to be associated with ... Saita S, Shirane M, Natume T, Iemura S, Nakayama KI (May 2009). "Promotion of neurite extension by protrudin requires its ... Shirane M, Nakayama KI (November 2006). "Protrudin induces neurite formation by directional membrane trafficking". Science. 314 ... "Role of spastin and protrudin in neurite outgrowth". Journal of Cellular Biochemistry. 113 (7): 2296-307. doi:10.1002/jcb.24100 ...
Chada, S; Lamoureux, P; Buxbaum, RE; Heidemann, SR (May 1997). "Cytomechanics of neurite outgrowth from chick brain neurons". ... Willits, Rebecca Kuntz; Skornia, Stacy L. (January 2004). "Effect of collagen gel stiffness on neurite extension". Journal of ...
Bryan B, Cai Y, Wrighton K, Wu G, Feng XH, Liu M (February 2005). "Ubiquitination of RhoA by Smurf1 promotes neurite outgrowth ...
... , or neuron reconstruction is a technique used in neuroscience to determine the pathway of the neurites or ... Helmstaedter M, Briggman KL, Denk W (2011). "High-accuracy neurite reconstruction for high-throughput neuroanatomy". Nat ...
"TMEM230 Accumulation in Granulovacuolar Degeneration Bodies and Dystrophic Neurites of Alzheimer's Disease". J. Alzheimer's Dis ...
Wiemerslage L, Lee D (March 2016). "Quantification of mitochondrial morphology in neurites of dopaminergic neurons using ...
"Tropomyosin localization reveals distinct populations of microfilaments in neurites and growth cones". Mol Cell Neurosci. 8 (6 ...
Sometime between day 1.5 and day 3, one of the minor neurites begins to outgrow the other neurites significantly. This neurite ... E Meijerings article on the state of neurite detection NeuronJ neurite tracing program Synd synapse and neurite detection ... The developing neurite sums together all of these growth signals in order to determine which direction the neurite will ... 30% of the time, a neurite not destined to become the axon protrudes from the cell body first. 10% of the time, the neurite ...
This review examines the use of neuronal cell cultures as an in vitro model of neurite outgrowth. Examples of the cell culture ... Developmental neurotoxicity testing in vitro: models for assessing chemical effects on neurite outgrowth Neurotoxicology. 2008 ... Issues relating to the relevance of the methods and models currently used to assess neurite outgrowth are discussed in the ... To demonstrate the utility of in vitro models of neurite outgrowth for the evaluation of large numbers of chemicals, efforts ...
Availability: Simple Neurite Tracer is open source software, licensed under the GNU General Public Licence (GPL) and based on ... Simple Neurite Tracer: open source software for reconstruction, visualization and analysis of neuronal processes Bioinformatics ... The software and further documentation are available via as part of the package Fiji, and ... which we call the Simple Neurite Tracer. ...
2012) The effect of glial fibrillary acidic protein expression on neurite outgrowth from retinal explants in a permissive ...
Neurite initiation is the first step in neuronal development and occurs spontaneously in soft tissue environments. Although the ... Paxillin facilitates timely neurite initiation on soft-substrate environments by interacting with the endocytic machinery. ... Paxillin facilitates timely neurite initiation on soft-substrate environments by interacting with the endocytic machinery ... Paxillin facilitates timely neurite initiation on soft-substrate environments by interacting with the endocytic machinery ...
Neurites turn at the edge of LN1 (red), but crossover without myosin II (right).BRIDGMAN/MACMILLANMyosin II pulls growth cones ... Normally, growing neurites rapidly retreat from polyornithine and turn back into the laminin surface. But when myosin II ... As this motor generates force on the cytoskeleton, he figured it might be involved in turning neurites in response to guidance ... Such was the case for LN1, as shown by the growth of neurites at borders between LN1 and polyornithine substrates. ...
First-in-Man Intrathecal Application of Neurite Growth-Promoting Anti-Nogo-A Antibodies in Acute Spinal Cord Injury ... BACKGROUND Neutralization of central nervous system neurite growth inhibitory factors, for example, Nogo-A, is a promising ... BACKGROUND Neutralization of central nervous system neurite growth inhibitory factors, for example, Nogo-A, is a promising ... First-in-Man Intrathecal Application of Neurite Growth-Promoting Anti-Nogo-A Antibodies in Acute Spinal Cord Injury. ...
Our findings suggest that Akt signaling regulates neurite outgrowth by stabilizing radixin interactions with F-actin, thus ... Our findings suggest that Akt signaling regulates neurite outgrowth by stabilizing radixin interactions with F-actin, thus ... Our findings suggest that Akt signaling regulates neurite outgrowth by stabilizing radixin interactions with F-actin, thus ... Our findings suggest that Akt signaling regulates neurite outgrowth by stabilizing radixin interactions with F-actin, thus ...
Yan, R. Reticulon 3 aggregation and its role in the formation of dystrophic neurites. Mol Neurodegeneration 7 (Suppl 1), L23 ( ... Reticulon 3 aggregation and its role in the formation of dystrophic neurites. *Riqiang Yan1 ... Reticulon 3 aggregation and its role in the formation of dystrophic neurites ... forming what are known as dystrophic neurites (DNs). However, the mechanisms by which DNs affect cognitive function in AD ...
Neurite tension following experimentally induced neurite slackening. An axonal neurite of a cell after approx. 2 days in ... Neurite tension following experimentally induced neurite slackening. An axonal neurite of a cell after approx. 2 days in ... De novo neurite initiation by application of tension distal to the neurite. (A) Approx. 8 hours following plating, tension is ... De novo neurite initiation by application of tension distal to the neurite. (A) Approx. 8 hours following plating, tension is ...
Dystrophic neurites express C9orf72 in Alzheimers disease brains Chromosome 9 open reading frame 72 (C9orf72) is an ...
The cost function has two terms: the neurite cost, which penalises pixels less likely to belong to neurites, and the ... Myatt, D.R., Nasuto, S.J. Improved automatic midline tracing of neurites with Neuromantic. BMC Neurosci 9 (Suppl 1), P81 (2008 ... Meijering E, Jacob M, Sarria JCF, Steiner P, Hirling H, Unser M: Design and Validation of a Tool for Neurite Tracing and ... It was found that by increasing the exponent of the neurite cost term, the midline tracking and length estimation of the ...
Measurement of neurite outgrowth using an automated image-based assay can be of use in the research, screening and validation ... Moreover, a neurite outgrowth assay can also be used for testing toxic neuropathies. Recombinant SH-SY5Y cells stably ... These cells constitutively express the TagGFP2-tubulin fusion protein.Assay Details: The growth of neurites in human neurons is ... designed to assay for compounds that positively affect neuritogenesis quantifying the number and length of neurites. ...
RGD ligands on coated surfaces while maintaining uniform protein surface coverage results in enhanced neurite extension of PC- ... RGD ligands on coated surfaces while maintaining uniform protein surface coverage results in enhanced neurite extension of PC- ... neurite length , 1 cell body diameter) and neurite length (neurite length , 2 cell body diameters) with increasing RGD surface ... For each image, cells with neurites greater than one cell diameter and cells with neurites greater than two cell diameters were ...
... failed to rescue neurite length. I, Quantification of neurite length. The average neurite length of wild-type control ... 1M,N, insets). In wild-type neurites, filaments were bundled (Fig. 1C,D,K,L, arrows), whereas in Srf mutants, the neurite shaft ... For neurite length the largest distance between neurites of one neuron was measured using Axiovision software. For growth-cone ... G15S actin enhanced neurite outgrowth and filopodia number. In contrast, R62D reduced neurite length and impaired growth-cone ...
now reveal a role for SORLA in promoting neurite growth.. SORLA-overexpressing hippocampal neurons grew longer neurites than ... Soluble SORLA promotes neurite regeneration in cultured cortical neurons after wound injury. Neurons were stained for tubulin ( ... Increases in neurite extension were accompanied by increased phosphorylation of the epidermal growth factor receptor (EGFR) and ... Alzheimers-Linked SORLA Protein and Neurite Growth. Jessica Stupack, Xiao-Peng Xiong,Lu-Lin Jiang, Tongmei Zhang,Lisa Zhou, et ...
Since neurites frequently crossed and fasiculated, tracing individual neurites to measure length was not possible. Instead we ... Growing neurites are guided to their destinations by combinations of soluble and immobilized chemical guidance cues1,2,3. ... Laminin, a ubiquitous component of basement membranes33, is known to promote neurite outgrowth in many contexts2,34,35,36. We ... Lectins from Aplysia hemolymph have been characterized30,31 and a lectin from Aplysia gonad promotes neurite outgrowth52. ...
6a-c) could also drive neurite outgrowth. Indeed, neurite outgrowth increased on laminin and myelin by PCAF overexpression in ... average neurite length analysis (h) and western blot and intensity analyses (i). (j,k) In addition, neurite outgrowth in ex ... Figure 6: ERK kinase inhibition blocks neurite outgrowth after conditioning lesion.. (a-c) PD98059 when applied at the nerve ... average neurite length analysis (k). Error bars, s.e. (b,c,e,h,i,k) P,0.0001, ANOVA, Bonferroni post hoc tests, *P,0.05, **P, ...
Myelin associated glycoprotein (MAG) - modulation of neurite outgrowth Another example where NMR spectroscopy plays a key role ... Mailänder) in Lübeck we have succeeded to establish neurite outgrowth assays to test the activity of potential inhibitors of ... Myelin associated glycoprotein (MAG) - modulation of neurite outgrowth. *Glycosyltransferases as key players in ... The overall goal in this project is the design of inhibitors of MAG that would eventually allow to promote neurite outgrowth ...
Neurite outgrowth gene-set analysis. Based on our finding that SEMA6D - a gene with a prominent role in neuronal migration and ... We found a significant association between a pre-defined gene-set of 45 neurite outgrowth genes24 and the meta-analytic data ... This finding is consistent with prior research implicating neurite outgrowth dysregulation in ADHD24,32, and highlighting it as ... Gene-set analysis in the ADHD-ICV meta-analytic data showed significant association with variation in neurite outgrowth-related ...
Deletion of exon L in Neuro2A or embryonic stem cells inhibited neurite outgrowth. Our results suggest that SRRM4 controls ... Deletion of exon L in Neuro2A or embryonic stem cells inhibited neurite outgrowth. Our results suggest that SRRM4 controls ... Deletion of exon L in Neuro2A or embryonic stem cells inhibited neurite outgrowth. Our results suggest that SRRM4 controls ... Deletion of exon L in Neuro2A or embryonic stem cells inhibited neurite outgrowth. Our results suggest that SRRM4 controls ...
Altogether, our results show for the first time that GPM6a is expressed in the PNS and participates in neurite extension. These ... Furthermore, blocking GPM6a using a structural monoclonal anti-GPM6a antibody significantly decreased neurite outgrowth in ... 031 , Neuronal Glycoprotein GPM6a Promotes Neurite Outgrowth in Dorsal Root Ganglion (DRG) Neurons ...
Here we show that FANCC and UNC5A are localized to regions of neurite outgrowth during neuronal cell differentiation. We also ... show that absence of FANCC is required for neurite outgrowth. In addition, FANCC seems required for UNC5A expression. Results ... Huang, F., Ben Aissa, M., Lévesque, G. et al. FANCC localizes with UNC5A at neurite outgrowth and promotes neuritogenesis. BMC ... FANCC and UNC5A co-localize to neurite outgrowth. a, b Representative microscopic images of SH-SY5Y cells incubated with RA (10 ...
... confirming the role of TopIIβ in neurite outgrowth. Together, these results demonstrate a critical role of TopIIβ in neurite ... confirming the role of TopIIβ in neurite outgrowth. Together, these results demonstrate a critical role of TopIIβ in neurite ... confirming the role of TopIIβ in neurite outgrowth. Together, these results demonstrate a critical role of TopIIβ in neurite ... confirming the role of TopIIβ in neurite outgrowth. Together, these results demonstrate a critical role of TopIIβ in neurite ...
Developmental switch in NF-κB signalling required for neurite growth Núria Gavaldà, Núria Gavaldà ... 2B,E) in the neurite arbors of E17 nodose neurons cultured with BDNF, and caused clear shifts in the Sholl profiles(Fig. 2C,F ... NF-κB activation in late foetal neurons is required for BDNF-promoted neurite growth. We have previously shown that NF-κB ... NF-κB activation is required for BDNF-promoted neurite growth from E17 nodose neurons. (A-C) Length (A), branch point number (B ...
The total length of neurites (B), the mean length of neurites (C) and the number of branches of neurites (D) were measured. n= ... The number of branches of neurites (B), the total length of neurites (C) and the mean length of neurites (D) were measured. n=7 ... G-I), Neurite branch length density: total length of neurite branches in the block/the volume of the block. n=10/group. **p, ... Additionally, the velocity of the neurites branches density increased was calculated by dividing the changes of neurite branch ...
... lactate treatment or overexpression of the active form of AMPK decreased α-syn turnover and neurite outgrowth; and (5) Lewy ... lactate treatment or overexpression of the active form of AMPK decreased α-syn turnover and neurite outgrowth; and (5) Lewy ... lactate treatment or overexpression of the active form of AMPK decreased α-syn turnover and neurite outgrowth; and (5) Lewy ... lactate treatment or overexpression of the active form of AMPK decreased α-syn turnover and neurite outgrowth; and (5) Lewy ...
Dive into the research topics of Vascular endothelial growth factor stimulates neurite outgrowth from cerebral cortical ... Vascular endothelial growth factor stimulates neurite outgrowth from cerebral cortical neurons via Rho kinase signaling. ...
BDNF and NT4/5 promote survival and neurite outgrowth of pontocerebellar mossy fiber neurons. In: Journal of Neurobiology. 1999 ... BDNF and NT4/5 promote survival and neurite outgrowth of pontocerebellar mossy fiber neurons. Journal of Neurobiology. 1999;40( ... BDNF and NT4/5 increased BPN neuron survival, neurite outgrowth, growth cone size, and elongation rate, while neither NT3 nor ... In addition, BDNF and NT4/5 reduced the size of neurite bundles. Consistent with these effects, in situ hybridization on ...
Aggregation of huntingtin in neuronal intranuclear inclusions and dystrophic neurites in brain. Science. 1997. 277:1990-1993. ... and that cortical and striatal neurites contain numerous aggregates (11, 27). Postmortem studies of HD brains also show ... Aggregates also develop in neurites. The aggregates are ubiquitinated, although antibodies against huntingtin appear to stain ...
  • Co-culture of neurons with electrically aligned glial tissue also directs neurite outgrowth, as it is rich in neurotrophins that promote nerve growth[citation needed]. (
  • We present an application for semi-automated tracing of neurons to quickly annotate noisy datasets and construct complex neuronal topologies, which we call the Simple Neurite Tracer. (
  • Myosin II pulls growth cones in the right direction, as shown by Stephen Turney and Paul Bridgman (Washington University, St. Louis, MO).Growing neurons in the developing embryo are directed by guidance cues such as laminin-1 (LN1), which steer the extension of neurite growth cones. (
  • Mechanical tension is a direct and immediate stimulus for neurite initiation and elongation from peripheral neurons. (
  • We report here that the relationship between tension and neurite outgrowth is equally initimate for embryonic chick forebrain neurons. (
  • Neurite outgrowth can be initiated de novo by experimental application of tension to the cell margin of forebrain neurons placed into culture 8-12 hours earlier, prior to spontaneous neurite outgrowth. (
  • Experimentally induced neurite elongation from these neurons shows the same robust linear relationship between elongation rate and magnitude of applied tension as peripheral neurons, i.e. both show a fluid-like growth response to tension. (
  • Although forebrain and sensory neurons manifest a similar distribution of growth sensitivity to tension (growth rate/unit tension), chick forebrain neurons initiated and elongated neurites at substantially lower net tensions than peripheral neurons. (
  • Neurites that were slackened showed only transient elastic behavior and never actively produced tension, as do chick sensory neurons after slackening. (
  • These cells constitutively express the TagGFP2-tubulin fusion protein.Assay Details: The growth of neurites in human neurons is a critical event in neuronal development, formation and remodeling of synapses, response to injury, and regeneration. (
  • Overexpressing these mutant actins in mouse hippocampal neurons not only modulated growth-cone function but also neurite elongation, which was ambiguous by traditional pharmacological interference. (
  • During brain development, neurons pass through various phases of morphological differentiation encompassing neurite elongation, neurite differentiation in axon and dendrites, and directional navigation of growth cones toward postsynaptic targets. (
  • Isolated Aplysia neurons have also become valuable tools for investigating the basic biology of neurite growth and regeneration. (
  • SORLA-overexpressing hippocampal neurons grew longer neurites than wild-type neurons in culture, and after a pipette tip was used to mechanically wound cultured cortical neurons, neurites from SORLA-overexpressing neurons grew more quickly into the wound area. (
  • Indeed, purified soluble SORLA produced by transfected HEK cells enhanced neurite growth in wild-type hippocampal and cortical neurons. (
  • Soluble SORLA promotes neurite regeneration in cultured cortical neurons after wound injury. (
  • We showed that the TopII inhibitor ICRF-193 significantly blocked neurite outgrowth and growth cone formation in cultured cerebellar granule neurons (CGNs), dorsal root ganglions (DRGs) and cortical neurons (CNs). (
  • Isolated cortical neurons from top2β knockout embryos elaborated shorter neurites than did those from their wild type counterparts, confirming the role of TopIIβ in neurite outgrowth. (
  • Together, these results demonstrate a critical role of TopIIβ in neurite outgrowth in cultured neurons. (
  • We show that although NF-κB signalling is required for BDNF-promoted neurite growth from both foetal and postnatal mouse sensory neurons, there is a developmental switch between these stages in the NF-κB activation mechanism and the phosphorylation status of the p65 NF-κB subunit required for neurite growth. (
  • In this thesis, I initially investigated whether attachment to permissive culture substrates is sufficient to promote neurite outgrowth from DRG neurons, and whether this interaction is able to enhance the response of neurons to added neurotrophic factors, such as NGF. (
  • Adult Dorsal Root Ganglion (DRG) neurons plated on surfaces coated with a thin film of laminin exhibited increased neurite outgrowth, this growth was correlated with increased expression of laminin binding integrin subunits. (
  • In performing these experiments it was observed that not all DRG neurons were responding to laminin and NGF with increased neurite growth. (
  • As neurons in the adult rat DRG can be classified into at least three separate subpopulations based on morphologic and phenotypic differences, a cell selection approach was utilized to show that laminin-induced neurite growth occurs in the absence of added trophic factors only in heavy chain neurofilament positive and calcitonin gene related peptide positive DRG neurons (NGF-responsive population). (
  • In contrast, laminin alone is not sufficient to stimulate significant neurite growth from lectin Griffonia simplicifolia 1B4 positive neurons (IB4+ve), although it is still required to elicit a growth response from these cells in the presence of Glial Cell Line Derived Neurotrophic Factor (GDNF) (e.g., neurite growth occurred only when cells were plated on laminin in the presence of GDNF). (
  • Further analysis indicated that Src was potentially a key point of collaboration between NGF and laminin induced neurite growth in NGF-responsive adult DRG neurons. (
  • In this series of studies we have identified specific signalling events and environmental requirements associated with neurite growth for different subpopulations of adult DRG neurons, pointing to potential therapeutic targets while identifying why any one treatment alone maybe insufficient to totally repair peripheral nerve damage. (
  • FLIP-L overexpression significantly enhances neurotrophin-induced neurite outgrowth in motoneurons, superior cervical ganglion neurons, and PC12 cells. (
  • Altogether, we uncover a new role for FLIP-L as an unexpected critical player in neurotrophin-induced mitogen-activated protein kinase/ERK- and NF-kappaB-mediated control of neurite growth in developing neurons. (
  • The focus of the present study was to develop a high-throughput 3D neurite outgrowth assay using iPSCderived neurons developed in the microfluidic OrganoPlate ® platform, with the goal of establishing 3D models for neurodegenerative diseases and neurotoxicology screens 3 . (
  • A glycoprotein called laminin promotes neurite extension in cultured neurons. (
  • This photomicrograph of a neural tissue specimen, harvested from a scrapie affected mouse, revealed the presence of prion protein stained in red, which was in the process of being trafficked between neurons, by way of their interneuronal connections, known as neurites. (
  • The 2 major neuropathologic findings in Parkinson disease are loss of pigmented dopaminergic neurons of the substantia nigra pars compacta and the presence of Lewy bodies and Lewy neurites. (
  • Sub-cytotoxic concentrations of CPF and its metabolite CPF-oxon (CPO) were known to inhibit neurite outgrowth in differentiating neural cells but little was known about their ability to cause neurite retraction. (
  • To evaluate the feasibility of the OrganoPlate platform for testing neurotoxicity and neuronal development, these neuronal cultures were treated with a selection of compounds known to inhibit neurite outgrowth 7 . (
  • By using chemical inhibitors we demonstrated that only the PI3-K/Akt pathway was required for neurite growth from the NGF-responsive cell population. (
  • However, both the PI3-K/Akt and MEK/MAPK signalling pathways were required for neurite growth from the IB4+ve cell population. (
  • Weak endogenous electric fields may be used to both facilitate and direct the growth of projections from cell soma neurites, EFs of moderate strength have been used to direct and enhance neurite outgrowth in both murine, or mouse, and xenopus models. (
  • The overall goal in this project is the design of inhibitors of MAG that would eventually allow to promote neurite outgrowth and to finally heal pathological conditions such as quadriplegia. (
  • As confirmation that ligand density in these engineered systems impacts neuronal cell behavior, we demonstrate that increasing the density of fibronectin-derived RGD ligands on coated surfaces while maintaining uniform protein surface coverage results in enhanced neurite extension of PC-12 cells. (
  • The mechanism by which SRRM4 regulates neurite outgrowth has remained poorly understood, however. (
  • all positive tensions stimulate neurite outgrowth. (
  • Vitamin C has been demonstrated to stimulate neurite outgrowth, fibroblast adhesion during wound healing, and diminish xenobiotic-induced leukocyte hyperactivity and inflammation. (
  • Moreover, αSyn accumulates in the Lewy bodies and dystrophic neurites of all patients with idiopathic PD [ 63 , 88 ], implicating the protein in sporadic as well as familial forms of the disease. (
  • Alpha-synuclein immunostaining performed on 225 brains was used to identify Lewy bodies and Lewy neurites. (
  • Moreover these actin mutants affect neurite elongation, an actin function which by pharmacological actin interference was ambiguous. (
  • BDNF and NT4/5 increased BPN neuron survival, neurite outgrowth, growth cone size, and elongation rate, while neither NT3 nor NGF increased survival or outgrowth. (
  • The direction of neurite elongation is controlled by various environmental cues. (
  • Furthermore, we provide evidence that the unidirectional rotation of filopodia causes deflected neurite elongation, most likely via asymmetric positioning of the filopodia onto the substrate. (
  • Because previous work had shown that SORLA can be cleaved at the plasma membrane to release a soluble fragment extracellularly, the authors asked whether this soluble fragment was responsible for the effects on neurite growth. (
  • Moreover, a neurite outgrowth assay can also be used for testing toxic neuropathies. (
  • Dendrites and axons in the region surrounding the plaques may become damaged and swollen, forming what are known as dystrophic neurites (DNs). (
  • While characterizing the reticulon (RTN)/Nogo family of proteins, which have been shown to negatively regulate BACE1 activity, we found that RTN3, which is primarily neuronally expressed, accumulates in a distinct population of DNs called RTN3 Immunoreactive Dystrophic Neurites (RIDNs) in the brains of AD patients and in APP transgenic mice, an animal model for AD. (
  • Yan, R. Reticulon 3 aggregation and its role in the formation of dystrophic neurites. (
  • Sometime between day 1.5 and day 3, one of the minor neurites begins to outgrow the other neurites significantly. (
  • Furthermore, blocking GPM6a using a structural monoclonal anti-GPM6a antibody significantly decreased neurite outgrowth in dissociated DRG neuron cultures. (
  • We found that the neurite outgrowth velocity and motor functional recovery in the ICH plus HHcy group were significantly slower than that in the control group, indicating that homocysteine (Hcy) significantly impedes the neurite outgrowth recovery after ICH. (
  • Additionally, upregulation of pCAMK2A significantly increased neurite outgrowth recovery in ICH with HHcy. (
  • Then, our findings further indicate that Hcy significantly downregulates the phosphorylation level of calmodulin-dependent protein kinases 2 (CAMK2A) after ICH, which is associated with neurite outgrowth. (
  • Conversely, the downregulation of FLIP-L protein levels by specific RNA interference significantly reduces neurite outgrowth, even in the presence of the appropriate neurotrophin stimulus. (
  • It has been suggested that global inhibition is achieved by a long-range negative feedback signal released from the developed axon and taken up by the other neurite. (
  • Using hydrogel cultures, pharmacologic inhibition, and genetic approaches, we reveal that paxillin-linked endocytosis and adhesion are components of a bistable switch controlling neurite initiation in a substrate modulus-dependent manner. (
  • This project focuses on the investigation of the interaction of gangliosides with a glycoprotein called myelin associated glycoprotein (MAG) that is responsible for the inhibition of neurite outgrowth upon injuries of the central nervous system (CNS). (
  • Microtubule-associated Ser/Thre kinase 2 (MAST2), inhibits neurite outgrowth, and its inhibition therefore represents a potential therapeutic strategy. (
  • Acetylcholinesterase assays suggested that inhibition was not required for neurite retraction but could affect the severity of such effects. (
  • In collaboration with the plastic surgeons (Prof. Mailänder) in Lübeck we have succeeded to establish neurite outgrowth assays to test the activity of potential inhibitors of MAG before they are tested in animal models. (
  • Hagemann, PhD, T. L., and A. Messing, VMD, PhD. The Effect of Glial Fibrillary Acidic Protein Expression on Neurite Outgrowth from Retinal Explants in a Permissive Environment . (
  • The same concentrations of CPF and CPO also caused retraction of neurites in differentiating neuronal and glial populations of human ReNcells. (
  • At every given point along a developing neurite, there are receptors detecting both positive and negative growth cues from every direction in the surrounding space. (
  • As this motor generates force on the cytoskeleton, he figured it might be involved in turning neurites in response to guidance cues. (
  • Elongating neurites, tipped by growth cones, explore guidance cues in their environment for appropriate paths ( Tessier-Lavigne and Goodman, 1996 ). (
  • Although the mechanisms regulating the morphology of migratory cells on rigid substrates in cell culture are widely known, how soft environments modulate neurite initiation remains elusive. (
  • By contrast, on rigid substrates, cells develop extensive adhesions, increase RhoA activity and sequester paxillin from the endocytic machinery, thereby delaying neurite initiation. (
  • This cell line expresses green fluorescent tubulin marking the cell cytoskeleton and it can be easily differentiated using standardized protocols to promote the neurite outgrowth.Cells were then grown in the presence of G418. (
  • Recombinant SH-SY5Y cells stably expressing human tubulin TagGFP2 are intended to be use as in vitro model for neuronal differentiation studies, designed to assay for compounds that positively affect neuritogenesis quantifying the number and length of neurites. (
  • Depletion of SRRM4 in Neuro2A cells impaired inclusion of exon L in protrudin mRNA, resulting in the generation of a shorter protein isoform (protrudin-S) that is less effective at promoting neurite extension. (
  • Deletion of exon L in Neuro2A or embryonic stem cells inhibited neurite outgrowth. (
  • In addition, ICRF-193 also blocked neurite outgrowth and growth cone formation of PC12 cells undergoing NGF-induced differentiation. (
  • We found that R-Ras GAP is down-regulated during neurite formation in rat pheochromocytoma PC12 cells by nerve growth factor (NGF), which is blocked by the transient expression of R-Ras gap or dominant negative R-ras cDNA. (
  • These results show essential roles of R-Ras GAP in development and differentiation: its expression is needed for embryonic development of blood vessel barriers, whereas its down-regulation facilitates NGF-induced neurite formation of PC12 cells via maintaining activated R-Ras. (
  • The main aims of this study were to investigate the effects of CPF and CPO on the stability of neurites in pre-differentiated mouse N2a neuroblastoma and human ReNcell CX neural stem cells, and to relate toxicity to the regulation of cytoskeletal proteins involved in neural differentiation. (
  • Increased levels of phosphatase activity were observed following 8 h treatment, suggesting that organophosphate-induced neurite retraction in N2a cells is associated with early transient increases in NFH phosphorylation and ERK1/2 activation. (
  • High content analysis of immunofluorescently stained N2a cells showed that the induction of neurite retraction by both compounds was concentration-dependent. (
  • In the present study, plasma from rats undergoing intracranial self-stimulation (ICSS) produced neurite outgrowth in PC12-variant cells (PC12m3). (
  • The resulting protein (protrudin-L) promotes neurite outgrowth during neurogenesis. (
  • This β-tubulin protein plays a role in the growth of specialized nerve cell extensions called axons and dendrites (collectively called neurites). (
  • Studies show this protein is particularly important for the regrowth of neurites after injury. (
  • Also, probing neurites in gray matter assumes high microscopic diffusion anisotropy in both axons and dendrites, which is not supported by evidence. (
  • Among the known extracellular growth signals are netrin, a midline chemoattractant, and semaphorin, ephrin and collapsin, all inhibitors of neurite growth. (
  • In addition, soluble SORLA increased nuclear levels of the immediate early gene Fos, which promotes neurite outgrowth. (
  • Neurite initiation is the first step in neuronal development and occurs spontaneously in soft tissue environments. (
  • Collectively, we clarify the mechanism of HHcy-hindered neurite outgrowth recovery, and pCAMK2A may serve as a therapeutic strategy for promoting neurological recovery after ICH. (
  • Recently, it has been suggested that in vitro models could be used to screen for chemical effects on critical cellular events of neurodevelopment, including differentiation and neurite growth. (
  • This review examines the use of neuronal cell cultures as an in vitro model of neurite outgrowth. (
  • Examples of the cell culture systems that are commonly used to examine the effects of chemicals on neurite outgrowth are provided, along with a description of the methods used to quantify this neurodevelopmental process in vitro. (
  • Here, we evaluated neurite outgrowth and neurological functional recovery using simulated models of ICH with HHcy in vitro and in vivo. (
  • The neural cell adhesion molecule N-CAM simultaneously combines with another N-CAM and a fibroblast growth factor receptor to stimulate the tyrosine kinase activity of that receptor to induce the growth of neurites. (
  • Notably, inhibiting EGFR and/or a MAP kinase kinase inhibited the effects of soluble SORLA on neurite outgrowth and Fos translocation. (
  • A neurite growing in vivo is surrounded by thousands of extracellular signals which in turn can be modulated by hundreds of intracellular pathways, and the mechanisms for how these competing chemical signals effect the ultimate differentiation of neurites in vivo is not precisely understood. (
  • Moreover, NGF-dependent activation of two main intracellular pathways involved in the regulation of neurite outgrowth, extracellular signal-regulated kinases (ERKs) and nuclear factor kappaB (NF-kappaB), is impaired when endogenous FLIP-L is downregulated, although TrkA remains activated. (
  • Such was the case for LN1, as shown by the growth of neurites at borders between LN1 and polyornithine substrates. (
  • Myosin placement in relation to adhesion sites might pull neurites toward more LN1 and away from unwanted substrates. (
  • However, it has been reported that even in the absence of any extrinsic directional signals, neurites turn clockwise on two-dimensional substrates. (
  • Alternatively, it has been suggested that the buildup of axonal growth factors in the neurite destined to become the axon means there is a depletion of axonal growth factors by default, as they must compete for the same proteins. (
  • This causes the other neurites to develop into dendrites as they lack sufficient concentrations of axonal growth factors to become axons. (
  • On days 4 to 7, the remaining minor neurites will begin differentiating into dendrites. (
  • Actin filaments retain their dynamic properties in the neurite that will become the axon in order to push the microtubules bundles outward to extend the axon. (
  • In all other neurites however, the actin filaments are stabilized by myosin. (
  • G15S actin enhanced neurite outgrowth and filopodia number. (
  • Normally, growing neurites rapidly retreat from polyornithine and turn back into the laminin surface. (
  • Laminin-induced neurite growth was integrin-dependent as it was attenuated by treatment with either a cyclic Arg-Gly-Asp (RGD) peptide or a β1 integrin-blocking antibody (β1i). (
  • Src appeared to be located upstream of the PI3-K/Akt signalling pathway and was responsible for increased neurite growth induced by the addition of laminin and NGF together. (
  • The development of a neurite requires a complex interplay of both extracellular and intracellular signals. (
  • By morphological and behavioural tests, we suggest that Hcy impedes neurite outgrowth and neurological recovery after ICH. (
  • Vitamin C supplementation can boost neurite outgrowth, boost fibroblast adhesion, and diminish xenobiotic-induced immunocytes aggregation, according to these findings. (
  • Our results suggest that SRRM4 controls neurite outgrowth through regulation of alternative splicing of protrudin transcripts. (
  • In contrast, R62D reduced neurite length and impaired growth-cone filopodia formation. (
  • Formation of neurite networks was monitored over time using transmitted light imaging. (
  • Consequently, objectives of this study were to explore whether FANCC is required for neurite outgrowth processes. (
  • But when myosin II activity was inhibited, the neurites ignored the change in substrate and grew over polyornithine. (
  • In animal SCI models, intrathecal delivery of anti-Nogo-A antibodies promoted regenerative neurite growth and functional recovery. (
  • Immediately after birth, BDNF-independent constitutive activation of NF-κB signalling by serine phosphorylation of IκBα and constitutive dephosphorylation of p65 at serine 536 are required for BDNF-promoted neurite growth. (
  • In addition, BDNF and NT4/5 reduced the size of neurite bundles. (
  • Mitogen-inducible gene 6 is an endogenous inhibitor of HGF/Met-induced cell migration and neurite growth. (
  • Among such factors, SRRM4 is an important regulator of aspects of neural differentiation including neurite outgrowth. (
  • Microtubules made with altered β-tubulin proteins do not grow and shrink as they should, which prevents neurite growth. (
  • Young neurites are often packed with microtubule bundles, the growth of which is stimulated by neurotrophic factors, such as nerve growth factor (NGF). (
  • Increases in neurite extension were accompanied by increased phosphorylation of the epidermal growth factor receptor (EGFR) and several kinases downstream of this receptor, including ERK and MAP kinases. (
  • Altogether, our results show for the first time that GPM6a is expressed in the PNS and participates in neurite extension. (
  • A neurite or neuronal process refers to any projection from the cell body of a neuron. (
  • 0.5 to 1.5 days after being plated in culture, several minor neurites will begin to protrude out from the cell body. (
  • It is known that 60% of the time the first neurite that protrudes from the cell body will become the axon. (
  • 30% of the time, a neurite not destined to become the axon protrudes from the cell body first. (
  • 10% of the time, the neurite that will become the axon protrudes from the cell body simultaneously with one or more other neurites. (
  • Here we show that FANCC and UNC5A are localized to regions of neurite outgrowth during neuronal cell differentiation. (
  • Retraction of neurites was observed within 2 h of exposure by live cell imaging. (
  • Researchers suspect that abnormal growth of neurites within the brain leads to brain abnormalities that underlie intellectual disability and other neurological problems in some people with CFEOM3. (