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41.
Bio-catalyzer alpha.rho No.11 (Bio-normalyzer) and its by-product are natural health products made by yeast fermentation of glucose, Carica papaya Linn., Pennisetum pupureum Schum., and Sechium edule Swartz. Their effects on free radicals were examined by electron spin resonance spectrometry using spin trapping agent 5,5-dimethyl-1-pyrroline-1-oxide (DMPO). It was observed that both Bio-catalyzer and its by-product scavenged 95% of DMPO-OH spin adducts (89 x 10(15) spins/ml) generated by FeSO4-H2O2-diethylene triamine pentaacetic acid system at 45.45 mg/ml each. Five percent of DMPO-O2- spin adducts (27 x 10(15) spins/ml) generated by hypoxanthine-xanthine oxidase system and 11% of 1,1-diphenyl-2-picrylhydrazyl radicals (7 x 10(15) spins/ml) were quenched using 25 mg/ml of Bio-catalyzer while 5% of superoxide and nil DPPH radicals were scavenged by its by-product. Vivo tests showed that oral administration of 1-g/kg body weight of Bio-catalyzer significantly inhibited thiobarbituric acid reactive substances formation, which is an index of lipid peroxidation, in the FeCl3-induced epileptic focus of rats. These findings suggest that Bio-catalyzer or its by-product may be useful health foods against neural lipid peroxidation, traumatic epilepsy and aging.  相似文献   
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The induction of granulocyte and macrophage colony formation by the granulocyte-macrophage colony stimulating factor (GM-CSF) on bone marrow cells (BMC) was evaluated as a function of time in agar cultures. We found that while macrophage cell clusters were very abundant on the first two days of culture, granulocytic cell clusters did not appear until the third day. We also found that macrophage colonies were present from the fourth day of culture, while granulocyte colonies did not appear until the fifth day. When two day cell clusters were transferred to cultures with GM-CSF we observed that only macrophage-colonies developed. On the other hand, when four day clusters were transferred, both granulocyte and macrophage colony formation was obtained in a similar way as the one obtained when using GM-CSF with fresh BMC. Two day clusters did not respond to granulocyte colony stimulating factor (G-CSF) while fourth day clusters generated granulocytic colonies in a similar way as when G-CSF was used with fresh BMC. In order to test the hypothesis that granulocyte colony formation in these assays could be a result of the secretion of G-CSF by the macrophages previously induced by GM-CSF, lysates from macrophage colonies were used to induce colony formation on BMC. We observed that colonies, mainly granulocytic, were induced in a similar way as when G-CSF was used. Finally, the possibility that GM-CSF is just a macrophage inducer with the property to produce cells that secrete G-CSF is discussed.  相似文献   
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Neuro-2a cells incubated for 1 hour with 0.1 mM vanadate showed an increase in cell membrane permeability. This effect is dose dependent, e.g. with 0.01 mM, 0.1 mM and 1 mM vanadate, there was {20, 30 and 40% increase. In contrast, no alteration in permeability was observed in HEp-2 cells under the same conditions.Ethanol (3%, 1 h incubation) also enhanced membrane permeability. The increase was also greater with Neuro-2a cells ({80%) than with HEp-2 cells (~30%). When the cells were incubated with ethanol plus vanadate (0.1 mM), there was a marked potentiation ({200%) in cell membrane permeability in Neuro-2a cells, and again a lesser increase in permeability ({50%) with HEp-2 cells.These results seem to be due to a preferential effect of vanadate on passive permeability of Neuro-2a cells because parallel measurements demonstrate equal inhibition of (Na+K) ATPase with both Neuro-2a and HEp-2 cells.  相似文献   
44.
The hydrolytic activity of F1-ATPase isolated from rat liver was enhanced in the presence of NADH, FADH2, QH2 or reduced cyt c. The extent of this activation depended largely on substrate concentration. F1-ATPase sensitivity to bicarbonate or dinitrophenol activators decreased in the presence of any of those electron donors, which originated as well a slight sensitivity to oligomycin and a sensitivity increase to the inhibitory anion OCN-. In the presence of oxidized carriers the sensitivity to bicarbonate, dinitrophenol, or OCN- was not modified, and the enzyme remained oligomycin insensitive.  相似文献   
45.
Rat liver glutamate dehydrogenase (L-glutamate: NAD(P) oxidoreductase, deaminating) E.C. 1.4.1.3.) is inactivated by the mitochondrial matrix in combination with lysosomal preparations. Neither lysosomal or mitochondrial matrix extracts per se inactivate the enzyme appreciably under the conditions used. Fractionation of the matrix indicates that a low molecular weight factor is responsible for the potentiation of inactivation of glutamate dehydrogenase by lysosomes. Its absorption spectrum and chromatographic behaviour suggest that this factor is NADP.  相似文献   
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PARP inhibition can induce anti-neoplastic effects when used as monotherapy or in combination with chemo- or radiotherapy in various tumor settings; however, the basis for the anti-metastasic activities resulting from PARP inhibition remains unknown. PARP inhibitors may also act as modulators of tumor angiogenesis. Proteomic analysis of endothelial cells revealed that vimentin, an intermediary filament involved in angiogenesis and a specific hallmark of EndoMT (endothelial to mesenchymal transition) transformation, was down-regulated following loss of PARP-1 function in endothelial cells. VE-cadherin, an endothelial marker of vascular normalization, was up-regulated in HUVEC treated with PARP inhibitors or following PARP-1 silencing; vimentin over-expression was sufficient to drive to an EndoMT phenotype. In melanoma cells, PARP inhibition reduced pro-metastatic markers, including vasculogenic mimicry. We also demonstrated that vimentin expression was sufficient to induce increased mesenchymal/pro-metastasic phenotypic changes in melanoma cells, including ILK/GSK3-β-dependent E-cadherin down-regulation, Snail1 activation and increased cell motility and migration. In a murine model of metastatic melanoma, PARP inhibition counteracted the ability of melanoma cells to metastasize to the lung. These results suggest that inhibition of PARP interferes with key metastasis-promoting processes, leading to suppression of invasion and colonization of distal organs by aggressive metastatic cells.  相似文献   
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The understanding of global diversity patterns has benefitted from a focus on functional traits and how they relate to variation in environmental conditions among assemblages. Distant communities in similar environments often share characteristics, and for tropical forest mammals, this functional trait convergence has been demonstrated at coarse scales (110–200 km resolution), but less is known about how these patterns manifest at fine scales, where local processes (e.g. habitat features and anthropogenic activities) and biotic interactions occur. Here, we used standardized camera trapping data and a novel analytical method that accounts for imperfect detection to assess how the functional composition of terrestrial mammal communities for two traits – trophic guild and body mass – varies across 16 protected areas in tropical forests and three continents, in relation to the extent of protected habitat and anthropogenic pressures. We found that despite their taxonomic differences, communities generally have a consistent trophic guild composition, and respond similarly to these factors. Insectivores were found to be sensitive to the size of protected habitat and surrounding human population density. Body mass distribution varied little among communities both in terms of central tendency and spread, and interestingly, community average body mass declined with proximity to human settlements. Results indicate predicted trait convergence among assemblages at the coarse scale reflects consistent functional composition among communities at the local scale, suggesting that broadly similar habitats and selective pressures shaped communities with similar trophic strategies and responses to drivers of change. These similarities provide a foundation for assessing assemblages under anthropogenic threats and sharing conservation measures.  相似文献   
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