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1.
Our aim in this study was to investigate the effect of moderate acute alcohol administration on cysteine protease mediated neuronal apoptosis and nitric oxide production in the traumatic brain injury. A total of 29 adult Sprague–Dawley male rats weighing 250–300 g were used. The rats were allocated into four groups. The first group was the control (sham-operated) group in which only a craniotomy was performed, the others were alcohol, trauma and trauma + alcohol groups. Caspase-3 enzyme activity in the trauma group increased significantly in comparison with the control group. The alcohol given group showed a decreased caspase-3 enzyme activity compared to the trauma group. The level of caspase-3 enzyme activity in the alcohol + trauma group decreased in comparison to the trauma group. SF/FEL ratio of cathepsin-L enzyme activity in the trauma group was significantly higher than in the control group. Our results indicate that moderate alcohol consumption may have protective effects on apoptotic cell death after traumatic brain injury. Protective effects of moderate ethanol consumption might be related to inhibition of lysosomal protease release and nitric oxide production.  相似文献   
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In regressive corpora lutea, apoptosis of luteal cells, expression of monocyte chemoattractant protein-1 (MCP-1), and accumulation of monocytes/macrophages occur. However, whether these three events are correlated and what cell type expresses MCP-1 have yet to be determined. To clarify these issues, we performed histochemical examinations to determine the localization and the numbers of MCP-1 mRNA-containing cells, apoptotic cells, and monocytes/macrophages in corpora lutea of normally cycling rats. We found that the Mcp-1 gene is expressed in nonapoptotic steroidogenic luteal cells. Corpora lutea that contained MCP-1 mRNA-expressing cells increased in number at estrus together with those containing apoptotic luteal cells. When individual corpora lutea at estrus were analyzed, those with many MCP-1-expressing cells contained few apoptotic cells, and vice versa. These results collectively suggest the following pathway for apoptosis- and MCP-1-dependent regression of the corpus luteum: 1) luteal cells are induced to undergo apoptosis at estrus, and the activation of Mcp-1 gene expression follows in nonapoptotic luteal cells; 2) monocytes/macrophages are chemoattracted by MCP-1 toward corpora lutea containing apoptotic luteal cells; and 3) monocytes/macrophages invade corpora lutea and eliminate apoptotic luteal cells by phagocytosis.  相似文献   
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A method is described for the molecular weight distribution of DNA which is determined from sedimentation-velocity analysis. Knowing the distribution of sedimentation coefficients for a single DNA concentration it is possible to extrapolate such a distribution to infinite dilution of the solute in a simple way. Two versions (using two or three terms of a series) of extrapolating equations are considered and discussed in detail. The sedimentation coefficients distribution calculated from these equations differs only insignificantly with that obtained in a conventional way.  相似文献   
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Barrett's esophagus (BE) is a metaplastic process whereby the normal stratified, squamous esophageal epithelium is replaced by specialized intestinal epithelium. Barrett's is the only accepted precursor lesion for esophageal adenocarcinoma (EAC), a solid tumor that is rapidly increasing in incidence in western countries. BE evolves into EAC through intermediate steps that involve increasing degrees of dysplasia. Current histologic criteria are quite subjective and the clinical behavior of BE is highly variable and difficult to predict using these standards. It is widely believed that molecular alterations present in BE and EAC will provide more precise prognostic and predictive markers for these conditions than the current clinical and histologic features in use. In order to further define molecular alterations that can classify unique groups of BE and EAC, we utilized methylation microarrays to compare the global gene methylation status of a collection of normal squamous, BE, BE + high-grade dysplasia (HGD), and EAC cases. We found distinct global methylation signatures, as well as differential methylation of specific genes, that discriminated these histological groups. We also noted high and low methylation epigenotypes among the BE and EAC cases. Additional validation of those CpG sites that distinguished BE from BE + HGD and EAC may lead to the discovery of useful biomarkers with potential clinical applications in the diagnosis and prognosis of BE and EAC.  相似文献   
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A local isolate of Bacillus thuringiensis Mm2 had insecticidal activity against the larvae of Melolontha melolontha, Agelastica alni, Leptinotarsa decemlineata and Amphimallon solstitiale and produced a 65 kDa protein. SDS-PAGE profile of B. thuringiensis Mm2 was compared with those of 29 different Cry3Aa producers which verified Cry3Aa biosynthesis by the isolate. The cry3Aa gene of Mm2 was cloned, sequenced and the deduced amino acid sequence was compared with the cry3Aa sequences of ten different quaternary ranks. Its identity to these sequences ranged between 97.4% and 99.2%. The gene was next cloned into E. coli-Bacillus shuttle vector pNW33N and expressed at a low level in B. subtilis 168.  相似文献   
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Class B scavenger receptor type I (SR-BI), a multiligand membrane protein, exists in various organs and cell types. In the testis, SR-BI is expressed in two somatic cell types: Leydig cells and Sertoli cells. Unlike interstitially localized Leydig cells, Sertoli cells present within the seminiferous tubules keep contact with spermatogenic cells and form the tight junction to divide the seminiferous epithelium into the basal and adluminal compartments. In this study, the expression and function of SR-BI in rat Sertoli cells were examined with respect to dependency on the spermatogenic cycle, the plasma membrane polarity, and the pituitary hormone follicle-stimulating hormone (FSH). When the expression of SR-BI was histochemically examined with testis sections, both protein and mRNA were already present in Sertoli cells during the first-round spermatogenesis and continued to be detectable thereafter. The level of SR-BI mRNA expression in Sertoli cells was lower at spermatogenic stages I-VI than at other stages. SR-BI was present and functional (in mediating cellular incorporation of lipids of high density lipoprotein) at both the apical and basolateral surfaces of polarized Sertoli cells. Finally, SR-BI expression at both the protein and mRNA levels was stimulated by FSH in cultured Sertoli cells. These results indicate that SR-BI functions on both the apical and basolateral plasma membranes of Sertoli cells, and that SR-BI expression in Sertoli cells changes during the spermatogenic cycle and is stimulated, at least in cultures, by FSH.  相似文献   
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The alder leaf beetle (Agelastica alni L., Coleoptera: Chrysomelidae) causes approximately 10% of total economic damage to hazelnut product per year in Turkey. A. alni larvae are susceptible to several pathogens indigenous to the area in which these insects occur in Turkey. In the present study, in order to find a more effective and safer biological control agent against this common pest, we evaluated the various biological agents’ insecticidal activity during the four hazelnut seasons from 2002 to 2005 on the larvae of the alder leaf beetle collected from the vicinity of Trabzon, Turkey. The tested agents are 25 insect-originating bacteria, 2 bacterial toxins and 1 viral preparation. The results showed that the highest insecticidal activity was obtained by bacterial isolates at 1.8 × 109 bacteria/mL dose, within ten days on the larvae of A. alni. These are 90% for Bacillus thuringiensis biovar tenebrionis (4AA1), Bacillus sphaericus (Ar4, isolated from Anoplus roboris L., Col.: Curculionidae), and Bacillus thuringiensis (Mm2, isolated from Melolontha melolontha L., Col.: Scarabaeidae). Our results indicate that these isolates may be valuable as biological control agent.  相似文献   
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We hypothesized that dexanabinol can prevent neuronal death by protecting neuronal lysosomes from nitric oxide (NO)-mediated toxicity, and in turn, by suppressing the release of cathepsins during cerebral ischemia. Focal cerebral ischemia was induced in two sets of animals by permanent middle cerebral artery occlusion. The first set was used to monitor NO concentration and cathepsin activity, while the second was used for histological examination with hematoxylin and eosin, and TUNEL staining. In post-ischemic brain tissue, NO content and cathepsin B and L activity increased (p < 0.05). Dexanabinol treatment reduced NO concentration and cathepsin activity to the control level (p > 0.05). The number of eosinophilic and apoptotic neurons increased in the post-ischemic cerebral cortex (p < 0.05). However, dexanabinol treatment lowered both of these (p < 0.05). We conclude that dexanabinol might be a useful agent for the treatment of stroke patients.  相似文献   
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