Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.1.7 (acetylcholinesterase)
28,390 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Tegu lizards (Tupinambis teguixin) were studied to determine the presence of a homologue of the mammalian corticospinal tract. The sources of telencephalic efferent projections to the spinal cord were determined by evaluating the localization of retrogradely transported horseradish peroxidase applied in the cervical spinal cord. Labeled cells were present in subtelencephalic sites reported previously by other authors and, in addition, were found in the principal sensory and motor nuclei of the trigeminal nerve and in the nucleus of the posterior commissure. A telencephalospinal projection was identified, originating in the ventral caudal telencephalon. Histochemical staining revealed a high concentration of acetylcholinesterase in cells and neuropil in the same area. This tract is suggested to be homologous to the mammalian amygdalospinal tract. No reptilian homologue of the corticospinal tract was identified.
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PMID:A telencephalospinal projection in the Tegu lizard (Tupinambis teguixin). 280 55

The acetylcholinesterase (EC 3.1.1.7) in 50 microL of a 61-fold dilution of erythrocytes in water hydrolyzes acetylcholine during a timed 20-min reaction at 37 degrees C. The resulting choline is measured by use of choline oxidase coupled to peroxidase, with phenol and aminoantipyrene to give a pink product that absorbs maximally at 500 nm. For calibration, a choline iodide standard is included in each batch of up to 19 samples. Accuracy was assessed by using specific inhibitors and measuring choline in the presence of excess erythrocyte solution. The standard curve for the assay is linear to threefold the normal enzyme activity. Between-batch precision was 0.40 kU/L at a mean of 11.5 kU/L (CV 3.5%), and comparison with an acetylthiocholine procedure (x) gave a good correlation: y = 1.02x - 0.27 kU/L (r = 0.991). Long-term precision (10 months), assessed from three sets of assays of samples from 17 individuals, was 0.71 kU/L at a mean of 11.7 kU/L (CV 6.1%).
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PMID:An enzymatic method for erythrocyte acetylcholinesterase. 283 47

Murine embryonic cells including yolk sac prepared from 8-day embryos were co-infected with Abelson murine leukemia virus (A-MuLV) and/or a recombinant retrovirus containing large T and small t antigens, and early region of simian virus 40 (M-SV40). By coinfection with A-MuLV and M-SV40, megakaryoblastic cells were obtained in addition to mast cells and fibroblastic cells. However, following infection with A-MuLV or M-SV40 alone, no megakaryoblastic cells were detected, although mast cells and/or fibroblastic cells developed. The same results were obtained in several experiments. By single-cell transfer, 6 acetyl-cholinesterase (AchE)-positive clonal cell lines were established. Characteristics of megakaryocytes, such as AchE, glycoproteins IIb and IIIa, and platelet peroxidase were detected in two representative cells (C1 and C8). More significant changes expressing differentiation were observed following treatment with phorbol myristate acetate or pokeweed mitogen-stimulated murine spleen cell conditioned medium, although release of platelets was not observed. This is the first report showing development of megakaryocytic cells as the result of coinfection with retroviruses.
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PMID:Establishment of megakaryoblastic cell lines by coinfection of Abelson murine leukemia virus and recombinant SV40-retrovirus. 284 81

Embryonic neocortical tissue survives and differentiates when grafted to injured adult neocortex. While these transplants are readily innervated by the host cholinergic fibers, specific thalamic fibers fail to innervate them. The present study was designed to test whether changing the activity levels of the thalamic ventrobasal projection neurons would promote sprouting of their axons into the embryonic cortical implants placed in the barrel field cortex. To achieve this the main input to these thalamic neurons was eliminated two synapses away, by blocking the peripheral sensory input to the barrel field cortex. Adult hosts underwent unilateral transection of the infraorbital nerve and two days later the contralateral barrel field cortex was lesioned enough to insert an embryonic neocortical graft. Following a one month post-transplantation period we examined the amount of specific thalamic axon ingrowth into the transplants by injecting the ventrobasal nucleus with horseradish peroxidase. The control cases without prior nerve damage confirmed previous observations that ventrobasal nucleus neurons fail to innervate the implanted neocortex. Transection of the infraorbital nerve prior to transplantation resulted in an unprecedented ingrowth of specific thalamic axons into the transplants. There was no significant difference in the amount of thalamic fiber ingrowth into the transplants when the peripheral nerve was (transection) or was not (cautery) allowed to regenerate. However, transection of the infraorbital nerve permits the nerve to regenerate and at least partially reconnect the sensory periphery, thus leading to the possibility of functional integration of the neocortical transplants into the host trigeminal system. The morphology and distribution of host acetylcholinesterase-positive fibers that grow into the transplants under both experimental and control conditions were distinctly different from those of thalamic axons. These results provide the first demonstration of peripheral sensory nerve induction of regenerative propensity in specific thalamocortical projection neurons. The thalamic fiber ingrowth should lead to enhanced functional innervation of the neocortical implants and better incorporation of the graft into the adult host brain circuitry.
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PMID:Peripheral nerve transection induces innervation of embryonic neocortical transplants by specific thalamic fibers in adult mice. 284 83

Using a monoclonal antibody to bromodeoxyuridine, we studied the cell kinetics of human hepatocellular carcinoma, liver cirrhosis, chronic active hepatitis and alcoholic liver fibrosis. Specimens were taken either by biopsy or surgery and immediately incubated with 0.1% bromodeoxyuridine solution at 37 degrees C for 45 min. After in vitro labeling, the bromodeoxyuridine taken up by the nuclei of S-phase cells was determined by the avidin-biotin-peroxidase complex method, using an anti-bromodeoxyuridine monoclonal antibody as the first antibody. The number of positive nuclei in 1,000 hepatic cells was counted, and the bromodeoxyuridine labeling index was expressed per thousand. The mean bromodeoxyuridine labeling index +/- S.D. of the cancerous portion of hepatocellular carcinoma, the noncancerous portion of hepatocellular carcinoma, liver cirrhosis, chronic active hepatitis and alcoholic liver fibrosis were 64.1 +/- 31.3, 33.6 +/- 14.4, 23.2 +/- 20.8, 9.1 +/- 6.1 and 21.6 +/- 13.0, respectively. The mean bromodeoxyuridine labeling index of the hepatocellular carcinoma cancerous portion was statistically higher than that of any other group. There was no statistical difference by the t test or the Wilcoxon test between the noncancerous portion of hepatocellular carcinoma and liver cirrhosis, and these two groups were proved interdependent by chi 2 test (Fisher's exact test), whether they were subdivided by bromodeoxyuridine labeling index greater than or equal to 10 or not. Bromodeoxyuridine labeling index was not significantly correlated with the usual biochemical parameters such as serum AST, ALT, gamma-GTP, alkaline phosphatase, lactate dehydrogenase, cholinesterase, albumin, and alpha-fetoprotein.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:S-phase cells in diseased human liver determined by an in vitro BrdU-anti-BrdU method. 284 68

The dispositions of galactosyl-containing glycoconjugates were studied during postnatal development of the caudate putamen in mice. The binding of the lectin peanut agglutinin, which has an affinity for galactosyl B-1,3 N-acetylgalactosamine residues, was compared to acetylcholinesterase staining and tyrosine hydroxylase immunoreactivity in the immature and adult neostriatum. The binding of peanut agglutinin conjugated to horseradish peroxidase, in sections that were processed for peroxidase histochemistry, was extremely pronounced in the neostriatum through the first postnatal week and constituted ringlike or polygonally shaped structures, which, overall, produced a variegated mosaic. These structures consist of outer rims of dense lectin-associated reaction product surrounding lightly labeled centers. Lectin delineations of the neostriatal mosaic are no longer visible in the second postnatal week. When adjacent sections were processed for lectin binding or acetylcholinesterase histochemistry, the dense lectin binding sites represented borders of acetylcholinesterase-rich and -poor zones. The distribution of dense patches of tyrosine hydroxylase immunoreactive fibers and terminals also coincides with the acetylcholinesterase-rich zones during the same times, and thus the glycoconjugate-delineated boundaries can also be directly compared with the distribution of nigrostriatal dopaminergic projections. The findings presented here represent the first demonstration of a probe that recognizes apparent borders of neostriatal compartments during a limited period of development. They are consistent with previous observations made on transient glycoconjugate "hidden boundaries" during development of other central nervous system structures, including the somatosensory cortical barrel field, and thalamic and brainstem nuclei (Cooper and Steindler, '86a,b; Steindler and Cooper, in press). In those studies, glia were shown to be the major source of glycoconjugate-associated patterns, and thus, glia and glycoconjugates that they synthesize during pattern formation events may be involved in the formation and stabilization of neurochemically distinct components of the neostriatal mosaic.
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PMID:Glycoconjugate boundaries during early postnatal development of the neostriatal mosaic. 289 17

This investigation was carried out on the distribution of enkephalin-containing nerve fibres and terminals in the region of the nucleus basalis magnocellularis (NBM) of the rat. At the light microscope (LM) level, enkephalin-immunoreactive sites and endogenous choline acetyltransferase (ChAT) were demonstrated by employing the two-colour immunoperoxidase staining technique, using highly specific monoclonal antibodies against enkephalin and ChAT. A pharmacohistochemical procedure to reveal acetylcholinesterase (AChE)-synthesizing neurons combined with the peroxidase-antiperoxidase (PAP) immunocytochemical technique to detect endogenous enkephalins, provided ultrastructural data on the relationships of neuronal elements containing AChE and enkephalins in the region of the NBM. At the LM level, cholinergic neurons of the NBM were surrounded by a dense network of enkephalin-immunoreactive nerve fibres. Electron microscopic (EM) observations of histochemically characterized structures, that were first identified in the LM, revealed that intensely AChE-stained structures in the region of the NBM received sparse synaptic inputs from enkephalin immunoreactive terminals. Synaptic inputs of immunoreactive terminals onto intensely AChE-stained neuron cell bodies were not detected. Synaptic contacts onto proximal AChE-positive dendrites were sparse, but the density increased on more distal regions of the dendrites. All immunoreactive boutons studied established symmetrical synaptic contacts with AChE-positive post-synaptic structures. The pattern of the synaptic input to these cells differs strikingly from that onto typical globus pallidus neurons. The perikarya and dendrites of the latter neurons were characteristically ensheathed in immunoreactive synaptic boutons. Results are consistent with the view that enkephalin-like substances in the rat might be synaptic transmitters or neuromodulators in the area of the NBM and that cholinergic neurons of the NBM (Ch4) are integrated into the circuitry of the basal ganglia. Enkephalins may play an important role regulating the extrinsic cholinergic innervation of the neocortex.
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PMID:Distribution of enkephalin-immunoreactive nerve fibres and terminals in the region of the nucleus basalis magnocellularis of the rat: a light and electron microscopic study. 304 47

The activities of various enzymes present in brain homogenates were assayed biochemically (a) with no pretreatment, (b) following a standard microwave treatment in saline and (c) after a standard microwave treatment in formalin. All enzyme activity was lost after the microwave - formalin in treatment. Following microwave - saline treatment, the activities of alkaline phosphatase, 5'-nucleotidase, isocitrate and succinate dehydrogenases were reduced. In contrast, the activities of lactate and malate dehydrogenases were unchanged, and that of acetylcholinesterase apparently increased. Analogous outcomes were seen following attempted histochemical demonstrations of these enzymes. Thus satisfactory histochemical demonstration of all enzymes was achieved (except with alkaline phosphatase, lactate and malate dehydrogenases) following the microwave-saline pretreatment. Since acid phosphatase, catalase and peroxidase were also successfully demonstrated, it seems that microwave-saline pretreatments permit both retention of sufficient enzyme activity for histochemical demonstration to occur and retention of sufficient structural integrity for critical morphological investigations. Since the failure to stain the sites of lactate and malate dehydrogenases is not due to microwave inactivation of these enzymes, their demonstration may be possible by varying the staining procedures.
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PMID:Brain enzyme histochemistry following stabilization by microwave irradiation. 306 7

The labelling of olfactory bulb glomeruli following horseradish peroxidase lavage of the nasal cavity has been studied in the rat. In such conditions, atypical glomeruli, previously described according to their high acetylcholinesterase content, display a strong tracer accumulation. The course of afferent olfactory fibres could be followed along the lateral and dorsal surface of the olfactory bulbs. The primary olfactory axons ending in atypical glomeruli have been identified with horseradish peroxidase in electron microscopy. They differ significantly from classical olfactory terminals owing to the presence of large dense-cored vesicles accompanying small clear ones. Moreover, the olfactory terminals do not gather in dark nodules as they do classically in olfactory glomeruli. The study demonstrates that a subset of olfactory neuroreceptors displaying original ultrastructural characteristics projects selectively into atypical olfactory glomeruli. Ultrastructural features indicate that olfactory information processing taking place in the neuropil might be similar to that which occurs in typical glomeruli. Considered together, the atypical olfactory neuroreceptors, glomeruli and acetylcholinesterase-containing centrifugal fibres could constitute a new olfactory subsystem. This hypothesis is discussed by taking into account previous demonstration of other olfactory subsystems devoted to the processing of olfactory cues of fundamental biological importance.
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PMID:Atypical olfactory glomeruli contain original olfactory axon terminals: an ultrastructural horseradish peroxidase study in the rat. 317 81

A two-step colorimetric method that overcomes the difficulties of the classic 240 nm benzoylcholine assay for plasma cholinesterase has been adapted to a Cobas-Fara centrifugal analyser, using choline oxidase coupled with peroxidase/phenol/aminoantipyrine for detection of the choline produced. Reaction conditions of the main reaction are identical to those of the classical benzoylcholine assay. The described method was applied to 105 selected serum samples, previously classified by the Danish Cholinesterase Research Unit as homo- or heterozygous for the usual (U), atypical (A), fluoride-resistant (F), or silent (S) allelic variants. The method showed a distinct separation of the various phenotypes, with catalytic activity concentrations, dibucaine numbers, and fluoride numbers directly comparable to established reference values of the manual 240 nm benzoylcholine method.
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PMID:Plasma cholinesterase genetic variants phenotyped using a Cobas-Fara centrifugal analyser. 323 60


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