Peripheral nervous system structure

The neuropathological analysis of HIV-associated neuropathies should include the different central and peripheral nervous system structures associated with sensory pathways, including spinal cord, dorsal root ganglia (DRG), peripheral nerve, and cutaneous nerve fibers (Pardo et al. 2001) (Fig. 4.1). The majority of studies have focused on the evaluation of the peripheral nerve, often from sural nerve biopsies and the DRG. Few studies have examined the pathology of sensory pathways in the... 

The primary target of carbon disulfide appears to be the nervous system. Neurophysiological and behavioral effects as well as pathomorphology of peripheral nervous system structures have been reported in humans as well as animals. Acute exposure to high concentrations of carbon disulfide can result in fainting and loss of consciousness. These effects were observed in 36-39% of 123 persons exposed to carbon disulfide following an accidental release of carbon disulfide, hydrogen sulfide, and sulfuric acid from a viscose rayon factory in India (Kamat 1994). 

There is a second family of small lipid-binding proteins, the P2 family, which include among others cellular retinol- and fatty acid-binding proteins as well as a protein, P2, from myelin in the peripheral nervous system. However, members of this second family have ten antiparallel p strands in their barrels compared with the eight strands found in the barrels of the RBP superfamily. Members of the P2 family show no amino acid sequence homology to members of the RBP superfamily. Nevertheless, their three-dimensional structures have similar architecture and topology, being up-and-down P barrels. 

High amounts of somatostatin are found in the CNS, the peripheral nervous system, the gut and the endocrine pancreas whereas the kidneys, adrenals, thyroid, submandibular glands, prostate and placenta produce rather low amounts. In particular, the hypothalamus, all limbic structures, the deeper layers of the cerebral cortex, the striatum, the periaqueductal central grey and all levels of the major sensoty pathway are brain areas that are especially rich in somatostatin. Eighty percent of the somatostatin immunoreactivity in the hypothalamus is found in cells of the anterior periventricular nucleus (Fig. 1, [1]). The gut 5 cells of the mucosa and neurons, which are intrinsic to the submucous and... 

The neuropeptide Y (NPY) belongs to a family of peptides that includes peptide YY and pancreatic polypeptide, and it is associated with several diseases such as asthma, immune system disorders, inflammatory diseases, anxiety, depression and diabetes mellitus. NPY is found in the central and peripheral nervous system, and its biological functions are mediated by interactions with five receptor sub-types, i.e. Yl, Y2, Y4, Y5 and Y6. Several studies indicate that the feeding behavior is influenced by interactions between NPY and Yl and Y5. Deswal and Roy used Cerius descriptors and genetic function approximation QSAR to investigate the structural determinants for the inhibition potency of 24 compounds with the general structure 4 for the NPY Y5 receptor [31]. The best QSAR (H = 0.720,... 

FIGURE 4-10 Myelin formation in the peripheral nervous system. (A) The Schwann cell has surrounded the axon but the external surfaces of the plasma membrane have not yet fused in the mesaxon. (B) The mesaxon has fused into a five-layered structure and spiraled once around the axon. (C) A few layers of myelin have formed but are not completely compacted. Note the cytoplasm trapped in zones where the cytoplasmic membrane surfaces have not yet fused. (D) Compact myelin showing only a few layers for the sake of clarity. Note that Schwann cell cytoplasm forms a ring both inside and outside of the sheath. (Adapted with permission from Norton, W. T. The myelin sheath. In E. S. Goldensohn and S. H. Appel (eds), Scientific Approaches to Clinical Neurology. Philadelphia Lea Febiger, 1977, pp. 259-298.)... 

Zanetta, J. P. Structure and functions of lectins in the central and peripheral nervous system. ActaAnat. (Basel) 161 ISO-195, 1998. 

Since OPC block ChE selectively in every cholinergic structure (bland N-cholinoreceptive systems), practically all physiological systems and organs can be involved in a pathological process. At that, changes in activity of the central and peripheral nervous systems as well as the resulting impairments in respiratory and cardiac activities have a critical influence on an outcome of the poisoning. 

Lead (soft, Pb2+) Injuries to peripheral nervous system, disturbs heme synthesis and affects kidneys Pb2+ may replace Ca2+ with loss of functional and structural integrity. Reacts with sulfhydryl groups, replaces Zn2+ in 8-aminolevulinic acid dehydratase. 

Type XXVIII collagen belongs to the class of VWA domain-containing proteins. The primary structure is similar to type VI collagen. It is mainly a component of the basement membranes around Schwann cells in the peripheral nervous system. ... 

It is time to build a little more on the structure that we have established. To provide a concrete example, we shall consider one aspect of the peripheral nervous system, PNS. As discussed above, the efferent PNS carries information from the CNS to the muscles movement results. 

The fats also have a plastic function as they are included in cell membranes and other cell structures. The central and peripheral nervous systems are rich in lipids. PNFA are included in cell membranes, with their most significant function being the synthesis of cell hormones — prostaglandins. The properties of cell membranes as well as their interaction with external factors depend on the relation of PNFA concentration in cell components. In humans, prostaglandins are created not only in tissues but also in thrombocytes (thromboxanes) and in leucocytes (leukotrienes). The biological action of thrombocytes is extremely variant and depends on PNFA type which are the basis for fatty acid creation. 

Neurotoxicity can be defined as any adverse effect on the structure or function of the nervous system related to exposure to a chemical substance (US-EPA 1998, OECD 2004c). According to the TGD (EC 2003), neurotoxicity can be defined as the induction by a chemical of adverse effects in the central or peripheral nervous system, or in sense organs and a substance is neurotoxic if it induces a reproducible lesion in the nervous system or a reproducible pattern of neural dysfunction. ... 

Morphological (structural) changes in the central or peripheral nervous system or in special sense organs... 

Occasionally the nervous system becomes involved in myelomatosis, and a number of cases have been reported. The lesions in these patients include compression of neural structures by myeloma tissue or collapsed vertebra, herpes zoster, and amyloid infiltration of the peripheral nervous system. Although uncommon, a peripheral neuromyopathy in which there is no direct involvement of nerves or nerve roots has been reported, but the association of multiple myeloma with neuropathy and osteosclerotic lesion is rarer and even more unusual. Osuntokun et al. (05) has reported such a patient in Africa whose outstanding clinical features were widespread neuromyopathy associated with multiple myeloma, and general-... 

A variety of responses in the body to different adrenergic drugs are based on their relative selectivity when binding with various receptors, which are exclusively found in and unevenly distributed in effector structures (heart, cardiovascular system, lungs, brain, peripheral nervous system, etc.). 

Tetrodotoxin, an extremely poisonous heterocycle present in Japanese puffer fish (various species of Spheroides), exerts its action by blocking the sodium ion channels in the peripheral nervous system. Chemically it has an adamantane-like structure, namely octahydro-12 - (hydroxymethyl) - 2 - imino-5,7,9,1 Oa-dimethano- 10aH-[ 1,3] -dioxo-cino-[6,5-d]pyrimidine-4,7,10,11,12-pentol. When chemically dehydrated, it rehydrates in dilute acid.73 Methanol, and ammonia, can add similarly. Because 2-amino-1,6-dihydropyrimidine forms the central part... 

For more than 10 years, researchers have investigated different concepts of utilizing microsystems to contact single neurons or whole structures in the central and peripheral nervous system. 

Myelin Structure in the Central and Peripheral Nervous System. 540... 

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