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1.
The photoacoustic spectroscopic studies of purple pigmented leaves revealed the occurrence of anthocyanins and betalains in
some local weed species growing on soils with low moisture levels. The pigmentation intensities were higher in C4 plants than in C3 plants. An inverse correlation was observed between pigmentation intensities and soil moisture levels.
This work is a part of the UNEP Research Project granted to Prof. D. O. Hall, UNEP Coordinator, Department of Plant Sciences,
King’s College; London. 相似文献
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Influence of duodenal secretions and its components on release and activities of human brush-border enzymes 总被引:1,自引:0,他引:1
The in vitro effects of human duodenal secretions and various combinations of its components on activity and release of enzymes from the human brush border were examined. Sucrase retained activity for 90 min in duodenal secretions, and maltase was almost as stable; lactase lost activity rapidly and alkaline phosphatase was of intermediate stability. Inactivation of lactase could only be partly (50%) attributed to luminal proteases, bile salts and phospholipids played no role. Rate of release of an enzyme from the brush border bore no relationship to its rate of inactivation. When individual proteases were studied, elastase was the most potent for releasing disaccharidases from the brush border; trypsin was ineffective alone but augmented the effect of elastase. Sucrase and maltase were activated by proteolytic release, but activation was abolished by simultaneous exposure of brush borders to bile salts. Lactase was released and rapidly inactivated by proteinases, while alkaline phosphatase appeared to be inactivated without significant release. These results show that there are significant interactions between luminal factors which have been inapparent when studying them in isolation. Loss of functionally useful enzyme does not follow release of sucrase or maltase from the brush border into the lumen but does follow release of lactase. Study of the susceptibility of lactase to inactivation by luminal factors in the various forms of lactose intolerance is warranted. 相似文献
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Identification of different protein functions facilitates a mechanistic understanding of Japanese encephalitis virus (JEV) infection and opens novel means for drug development. Support vector machines (SVM), useful
for predicting the functional class of distantly related proteins, is employed to ascribe a possible functional class to Japanese encephalitis virus protein. Our study from SVMProt and available JE virus sequences
suggests that structural and nonstructural proteins of JEV genome possibly belong to diverse protein functions, are expected to occur in the life cycle of JE virus. Protein functions common to both structural and
non-structural proteins are iron-binding, metal-binding, lipid-binding, copper-binding, transmembrane, outer membrane, channels/Pores - Pore-forming toxins (proteins and peptides) group of proteins. Non-structural
proteins perform functions like actin binding, zinc-binding, calcium-binding, hydrolases, Carbon-Oxygen Lyases, P-type ATPase, proteins belonging to major facilitator family (MFS), secreting main terminal branch (MTB)
family, phosphotransfer-driven group translocators and ATP-binding cassette (ABC) family group of proteins. Whereas structural proteins besides belonging to same structural group of proteins (capsid, structural, envelope),
they also perform functions like nuclear receptor, antibiotic resistance, RNA-binding, DNA-binding, magnesium-binding, isomerase (intra-molecular), oxidoreductase and participate in type II (general) secretory pathway (IISP). 相似文献
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Vijay Pal Singh Rangoli Aggarwal Suchita Singh Arpita Banik Tanveer Ahmad Bijay Ranjan Patnaik Giridharan Nappanveettil Kunal Pratap Singh Madan Lal Aggarwal Balaram Ghosh Anurag Agrawal 《PloS one》2015,10(6)
Epidemiological studies have shown an increased obesity-related risk of asthma. In support, obese mice develop airway hyperresponsiveness (AHR). However, it remains unclear whether the increased risk is a consequence of obesity, adipogenic diet, or the metabolic syndrome (MetS). Altered L-arginine and nitric oxide (NO) metabolism is a common feature between asthma and metabolic syndrome that appears independent of body mass. Increased asthma risk resulting from such metabolic changes would have important consequences in global health. Since high-sugar diets can induce MetS, without necessarily causing obesity, studies of their effect on arginine/NO metabolism and airway function could clarify this aspect. We investigated whether normal-weight mice with MetS, due to high-fructose diet, had dysfunctional arginine/NO metabolism and features of asthma. Mice were fed chow-diet, high-fat-diet, or high-fructose-diet for 18 weeks. Only the high-fat-diet group developed obesity or adiposity. Hyperinsulinemia, hyperglycaemia, and hyperlipidaemia were common to both high-fat-diet and high-fructose-diet groups and the high-fructose-diet group additionally developed hypertension. At 18 weeks, airway hyperresponsiveness (AHR) could be seen in obese high-fat-diet mice as well as non-obese high-fructose-diet mice, when compared to standard chow-diet mice. No inflammatory cell infiltrate or goblet cell metaplasia was seen in either high-fat-diet or high-fructose-diet mice. Exhaled NO was reduced in both these groups. This reduction in exhaled NO correlated with reduced arginine bioavailability in lungs. In summary, mice with normal weight but metabolic obesity show reduced arginine bioavailability, reduced NO production, and asthma-like features. Reduced NO related bronchodilation and increased oxo-nitrosative stress may contribute to the pathogenesis. 相似文献
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C M van der Loos P K Das H J Houthoff 《The journal of histochemistry and cytochemistry》1987,35(11):1199-1204
For immunohistological analysis, simultaneous detection of multiple cellular epitopes, as compared to single staining of serial sections, is sometimes needed. Therefore, immunoenzyme triple-staining protocols were tested with polyclonal and monoclonal antibodies on tissue sections and cytospin preparations. Various immunoconjugates were used in different combinations of methods, of which not all proved to be suitable. Of the tested protocols, one yielded superior results for both monoclonal and polyclonal antibodies, with optimal preservation of their original avidity. The method consists of a combination of indirect, direct, and avidin-biotin complex technique. The three antigens can be distinguished clearly and selectively by the reaction products of the enzyme activities of beta-galactosidase (green), alkaline phosphatase (blue), and horseradish peroxidase (red). 相似文献