Effect of toluene inhalation on astrocytes and neurotrophic factor in rat brain

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.     

Lectin-histochemical detection of degenerative glycoconjugate deposits in human brain

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.     

美国对缅甸的政策

美国巩固在缅甸的政治地位的企图 由于缅甸处于有利的地理位置、它在东南亚国家中所起的政治影响以及蕴藏有富饶的自然资源(主要是战略资源),因此,它在美帝国主义的蓄谋侵略的计划中占据着重要的地位。 美国对缅甸感兴趣的首先在于军事战略和政治方面。关于这点,美国统治集团代表人物的演说以及美国的报刊屡屡谈及。美国国家计划协会委员哈     

现代泰国的经济概况

农业 泰国是一个落后的農业国,農业是其国民經济的主導部門:国内从事農业的人口占独立谋生人口的85％。侭管農業起着如此重要的作用,然而,它的内部结构却僅由两种商品——大米和橡胶的生产     

十九世紀最后廿五年馬来亚人民反对英国殖民主义者的起义

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     

柬埔寨的外国援助

西哈努克亲王最近从法国返国,西哈努克在法国逗留了将近七个星期,进行手术并作短期休息,众所周知,柬埔寨首相的奇異的经历和突出的个性:1955年3月西哈努克采取了史无前例的决定,放弃了王位的继承。自此以后,西哈努克亲王或者作为柬埔寨政府的首脑或者暂时退居于在野地位,都促进着柬埔寨的政治生活,並在东南亚地区执行不同路线的各个国家(亲美的国家如泰国、南越、甚至以及近几个月以来的老撾;亲共产主义国家如北越)之间,扮演着微妙的中立主义的战士和技师     

印度尼西亚财政政策及其影响

序言印度尼西亚的财政金融形势向来没有朝着好的方向发展,相反的,最近是更恶化了。这种情况是早为公众和政府所理解和承认的事实。还需要认真加以探讨的则是政府对财政困难的基本原因及其出路的意见。某些负责的政府官员和社会上的某些人士,更偏重于从货币流通量的发展情况这个角度来观察财政形势。用这种方法,他们甚至得出结论说:向来就是政府方面造成通货膨涨,所以国家预算必须压     

南越土地改革的进展

自从1954年7月日内瓦协定订立之后,南越吴庭艶政府把土地改革存在关键性的问题,下了绝大的决心,付诸实施,特别是在土地转移和定居这两个方面。在实施土改计划上,美国的经济和技术援助起了重要的作用。土改计划的初步阶段,现在将近完成,減租和稳定佃期的计划,现在正在继续施行,并普及到全国佃农的3/4,而土地转移计划预     

馬来亚橡膠問題

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。     

泰国大米輸出之研究

英格兰姆在1951—52年,曾以“社会科学研究基金”名义,前往泰国进行調查工作。从泰国返美后,曾任美国北卡罗里那大学經济学教授。本文譯自著者:“1850年后泰国經济的变革”一書第三章,該章主要是分析1850至1950年以来泰国大米生产及輸出的情况。从文章內容可看出泰国經济,特別是农业生产的殖民地性和对外国資本的依賴性。