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171.
Toluene, an abused substance in Japan, is a neurotoxic chemical that has been shown to have neurobehavioral and electrophysiological effects. In previous work, both acute and chronic effects of toluene on cells have been studied extensively. However, although glial cells are thought to play an important role in the survival of neurons in the brain, the effect of toluene on glial cell function has not yet been characterized. To elucidate this, the effect of toluene inhalation on astrocytes in rat brain was examined. Toluene exposure (1500 ppm for 4 h on 4-10 days) augmented glial fibrillary acidic protein (GFAP) immunoreactivity, particularly in the hippocampus and cerebellum. Quantitative analysis showed that toluene inhalation markedly enhanced GFAP expression in the hippocampus and cerebellum. In both regions, proliferating cell nuclear antigen (PCNA) showed no obvious changes, but glutamine synthetase (GS)-immunoreactive cells were markedly increased by toluene exposure. Thus, the elevation of GFAP expression was induced by astrocyte activation rather than by cell proliferation. If toluene exposure activates astrocytes, astrocytes may play a role in the neurophysiological changes observed in toluene intoxication. A neurotrophic factor, basic fibroblast growth factor (b-FGF) was observed immunohistochemically in the capillary vessel walls in the hippocampus and the cerebellum of toluene-intoxicated rats. Basic-FGF may have induced GFAP expression both in the hippocampus and the cerebellum. So, other neurotrophic factors may affect the difference of GFAP elevation between the hippocampus and the cerebellum. These differences may relate to neurobehavioral function of each brain part after toluene exposure.  相似文献   
172.
Several lectins were used to study the localization of glycoconjugates in brain of elderly people and patients with Alzheimer type dementia (ATD) and Down's syndrome (DS). Five kinds of degenerated or deposited materials stained clearly by lectins specific to GalNAC, Gal, Fuc, and/or Man were recognized much in ATD and DS, less in elderly peoples, in addition to the binding of the lectins to neurons. (i) Round shape deposits called corpora amylacea (CA) which consisted of various sizes of round material, existed mainly on the surface of cerebral cortex and some in white matter of the brain. They were colored by Alcian blue (AB), Aldehyde fucsin (AF) and periodic acid shiff (PAS) and weakly by Hematoxylin (H), but not by Eosin (B). They showed clear reactivity with lectins specific to GalNAC, Gal, Fuc and Gal-GalNAC. (ii) Amorphous and variform amyloid deposits existed around blood vessels in the white matter were stained by thioflavin and lectins specific to GalNAC, Gal and Fuc, but not with Man specific lectins and PAS, AB, AF and HE. (iii) Another kind of amyloid deposits which showed a similar characteristic to the previous one and were recognized mainly in white matter and independent blood vessels. These deposits were stained by thioflavin but not by PAS, AB, AF and HE and showed good reactivity with lectins specific to GalNAC, Gal, Fuc, Gal-GalNAC, Gal-GIcNAc and Man. The reactivity with lectins specific to Gal, Fuc, and Man was seen in senile plaques (iv) and neurofibrillary tangles (v). Although at present we are unable to explain the origin of these deposits, it is clear from this study that the glycoconjugates form an integral part of the degeneration in the brain. The lectin staining with GS-I is useful in the forensic pathology to diagnose brain disorders at postmortem examination, since these lectin were able to detect five types of degeneration changes and/or deposits.  相似文献   
173.
A fast method using liquid-liquid extraction and HPLC/tandem-mass spectrometry (LC/MS/MS) was developed for the simultaneous detection of 11-Nor-Delta(9)-tetrahydrocannabinol-9-carboxylic acid beta-glucuronide (THC-COOH-glucuronide) and 11-Nor-Delta(9)-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) in urine samples. This highly specific method, which combines chromatographic separation and MS/MS analysis, can be used for the confirmation of positive immunoassay results even without hydrolysis of the sample or derivatisation of extracts. Liquid-liquid extraction was optimised: with ethylacetate/diethylether (1:1, v/v) THC-COOH-glucuronide and THC-COOH could be extracted in one step. Molecular ions of the glucuronide (MH(+), m/z 521) and THC-COOH (MH(+), m/z 345) were generated using a PE/SCIEX turboionspray source in positive ionisation mode; specific fragmentation was performed in the collision cell of an API 365 triple-quadrupole mass spectrometer and yielded major fragments at m/z 345 (for THC-COOH-glucuronide) and m/z 327 as well as m/z 299 for both cannabinoids. Chromatographic separation was performed using a reversed-phase C8 column and gradient elution with 0.1% formic acid/1 mM ammonium formate and acetonitrile/0.1% formic acid. Retention times were 22.2 min for the glucuronide and 26.8 min for THC-COOH. After enzymatic hydrolysis of urine samples with beta-glucuronidase/arylsulfatase (37 degrees C, 5 h), THC-COOH-glucuronide was no longer detectable by LC/MS/MS in urine samples. However, the THC-COOH concentration was increased. For quantitation of THC-COOH, THC-COOH-D(3) was added to the urine samples as internal standard prior to analysis. From the difference of THC-COOH in the native urine and urine after enzymatic hydrolysis, molar concentration ratios of THC-COOH-glucuronide/THC-COOH in urine samples of cannabis users were determined and found to be between 1.3 and 4.5.  相似文献   
174.
A total of 36 ancient human remains from 12 individuals (three tooth/bone samples each) and one sample each of three individuals from the newest time was typed in a blind study using the amelogenin sex test. Prior to this molecular sex determination the sex of the individual was determined morphologically. The success rate of the amelogenin amplifications was >90%. For every individual an unambiguous molecular sex typing result was obtained. Furthermore, the morphological and molecular sex determinations were in accordance with each other, giving evidence for the authenticity and ancient origin of the polymerase chain reaction (PCR) amplifications.  相似文献   
175.
A number of DNA polymorphisms have been found to be associated with the pathophysiology of some common disease. If the LDLR polymorphism is directly or indirectly related to some fatal disease, the distribution of the polymorphism may vary with age. We therefore investigated the aging-associated distribution of the LDLR polymorphism. Blood samples were collected from Japanese cadavers (aged 0-91) at autopsy. The LDLR polymorphism was detected using a AmpliType PM PCR Typing kit. When the LDLR genotype was examined in cadavers divided according to age into 0-29 year group, 30-59 year group, and 60-91 year group, there were significant differences in genotype among the three age groups and between the 0-29 year group and 60-91 year group. The LDLR-A genotype tended to be lower in the older cadavers. The present study revealed that there were aging-dependent differences in the distribution of the LDLR polymorphism in autopsy samples, suggesting that a common mutation involved in the occurrence of fatal diseases may be present near the LDLR-A polymorphism locus.  相似文献   
176.
Papillary fibroelastoma is a rare benign tumor, occasionally causing angina or sudden death. We report an autopsy case of an aortic valve papillary fibroelastoma with coronary artery embolism. The patient was a 68-year-old Japanese man who had collapsed suddenly in his house. He was a heavy drinker and had a history of liver disease but no notable cardiac event. The autopsy revealed extensive transmural infarction of the inferior wall of the left and right cardiac ventricles. The distal portion of the right coronary artery (segment 4, NYHA) was completely occluded by tumor emboli of the fibroelastoma. At the site of closure of the aortic non-coronary cusp, there was a typical papillary fibroelastoma, which was considered to have originated the coronary embolization.  相似文献   
177.
178.
Household survey data on age at first use of alcohol, tobacco, marijuana,and hard drugs can be biased due to sample selection and inaccuraterecall. One potential concern is attrition, whereby individuals who getinvolved with substance use at an early age become increasingly less likelyto be surveyed in successive years. A comparison of data from the NationalHousehold Survey on Drug Abuse (NHSDA) with data from a longitudinal studysuggested that attrition might have caused substantially less bias thandid forward telescoping, the inflating of age at first useover time. The evidence of forward telescoping was particularly pronouncedwith respect to age at first use of alcohol. This paper presents a procedurefor correcting the distribution of age at first use for forward telescoping(but not attrition) by viewing a portion of the NHSDA data collected insuccessive years as constituting a cohort study. Results are presented fromapplying this procedure with NHSDA data collected from 1982 to 1995 forrespondents born 1968–1973. The findings suggest that preventionprograms need to be introduced at an earlier age than would be indicatedby uncorrected retrospective data. Other implications are alsohighlighted.  相似文献   
179.
不久以前,苏聯的研究工作者已經開始編篡一系列东南亚國家的近代史;其中對这些國家的民族解放運动史研究較少。本文則試图探討一下十九世纪70—90年代在馬來亚反對英国殖民主义者的起义。①內容广泛的英國歷史編篡学在關于英國佔领馬  相似文献   
180.
本文选譯自L.A.密尔斯著“馬来亚政治經济評述”一書第八章,標題为“天然橡胶和人造橡胶”。但全文主要內容是关于馬来亚天然橡胶的生产問題,因此改用現在標題。作者对于馬来亚战后以来天然橡胶的生产問題作了詳尽的論述,材料比較丰富,可供研究工作者参考。  相似文献   
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