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We examined the neuroprotective effects of oren-gedoku-to (TJ15), a herbal medicine, after transient forebrain ischemia. Transient forebrain ischemia was induced by occlusion of both common carotid arteries for 15 min in C57BL/6 mice treated with TJ15. In the control ischemic group without TJ15 treatment, histologic examination of brain tissue collected seven days after reperfusion showed death of pyramidal cells in CA2-3 area of the hippocampus, unilaterally or bilaterally. In mice treated with oral TJ15 (845 mg/kg/day) for five weeks, the frequency of ischemic neuronal death was significantly lower. Immunohistochemistry for Cu/Zn-superoxide dismutase (Cu/Zn-SOD) showed strongly reactive astrocytes in the hippocampus of ischemic mice treated with TJ15. Damage to nerve cells by free radicals plays an important role in the induction of neuronal death by ischemia-reperfusion injury. Our results suggest that TJ15 protects against ischemic neuronal death by increasing the expression of Cu/Zn-SOD and suggest that oren-gedoku-to reduces the exposure of hippocampal neurons to oxidative stress.  相似文献   
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GABA is synthesized by glutamate decarboxylase (GAD), which has two forms, GAD65 and GAD67. To elucidate the molecular mechanisms of mouse GAD65 (mGAD65) gene expression, we isolated and characterized the mGAD65 gene. The mGAD65 gene was found to be divided into 16 exons and spread over 75 kb. The sequence of the first exon and the 5'-flanking region indicated the presence of potential neuron-specific cis-regulatory elements. We used transgenic mice to examine the expression pattern conferred by a 9.2-kb promoter-proximal DNA fragment of the mGAD65 gene fused to the bacterial lacZ reporter gene. Transgenic mice showed high beta-galactosidase activity specifically in brain and testis. They also showed characteristic patterns of transgene expression in olfactory bulb, cerebellar cortex, and spinal cord, a similar expression pattern to that of endogenous mGAD65. However, no transgene expression was observed in the ventral thalamus or hypothalamus, in which high mGAD65 gene expression levels have been observed. These results suggest that the 9.2-kb DNA fragment of the mGAD65 gene is associated with its tissue-specific expression and its targeted expression in GABAergic neurons of specific brain regions but that additional regulatory elements are necessary to obtain fully correct expression.  相似文献   
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Mucin-type core 1-derived O-glycans, one of the major types of O-glycans, are highly expressed in mammary gland epithelium. Abnormal O-glycans such as Tn antigen are found in over 90% of breast cancers; however, the in vivo role of these aberrant O-glycans in the etiology of breast cancer is unclear. We generated mice with mammary epithelial specific deletion of core 1-derived O-glycans. By crossing with two spontaneous mouse breast cancer models, we determined that loss of core 1-derived O-glycans delays the onset and progression of breast cancer development. Deficiency of core 1 O-glycosylation impaired the localization of Muc1, a major O-glycoprotein, on the apical surfaces of mammary epithelium. Signaling mediated by Muc1, which is critical for breast cancer development, was also defective in the absence of core 1 O-glycans. This study reveals an unexpected role of core 1-derived O-glycans in breast cancer development in mice.  相似文献   
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Landscape and Ecological Engineering - Investigating factors underlying human-wildlife conflicts in agricultural landscapes is important for both preventing crop damage and wildlife conservation....  相似文献   
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Journal of Microbiology - The widespread use of the organochlorine insecticide lindane in the world has caused serious environmental problems. The main purpose of this paper is to investigate the...  相似文献   
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