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951.
Bharti AC Aggarwal BB 《Apoptosis : an international journal on programmed cell death》2004,9(6):677-690
Many members of tumor necrosis factor (TNF) superfamily are characterized by their ability to induce apoptosis once they bind in a homotrimeric manner to their cognate receptors. The receptor activator of nuclear factor-kappaB ligand (RANKL), a member of the TNF superfamily identified seven years ago, was originally described as a factor that induced osteoclastogenesis and dendritic cell survival. Recent observations indicate that a growth inhibitory and apoptosis-inducing activity is associated with RANKL, as is the case for other members of TNF superfamily. This review describes the possible mechanisms of induction of RANKL-induced growth inhibition/apoptosis and discusses the role of various components in RANKL-signaling in this phenomenon, including TNF receptor-associated factor (TRAF)-6, nuclear factor-kappaB (NF-kappaB), c-jun N-terminal kinase JNK), phosphatidylinositol-3 kinase (PI3K). 相似文献
952.
Toxicity to o-sec-butylphenyl methylcarbamate compound (BPMC) was analyzed in the rice brown planthopper, Nilaparvata lugens, using a differential proteomics approach of identifying proteins on two dimensional-polyacrylamide gel electrophoresis (2D-PAGE). Proteome analysis from BPMC-treated brown planthopper resulted in the modulation of 22 proteins at the expression level as compared to control samples on coomassie brilliant blue (CBB) stained gels. Out of total 22 proteins, 10 proteins showed elevated expression, eight proteins showed decreased expression and four proteins showed specific expression after insecticide treatment. The N-terminal sequences of seven out of 22 proteins were determined by a gas-phase protein sequencer. The internal amino acid sequences of the 15 proteins were determined by the sequence analyses of peptides obtained by Cleveland peptide mapping method and were compared with those of the known proteins available in public databases and the EST database of the brown planthopper in our laboratory to understand the nature of the proteins. Sequence analyses revealed that the expression of putative serine/threonine protein kinase, paramyosin, HSP 90, beta-tubulin, calreticulin, ATP synthase, actin and tropomyosin was elevated, and that of beta-mitochondrial processing peptidase, dihydrolipoamide dehydrogenase, enolase and acyl-coA dehydrogenase was reduced due to the exposure of BPMC. The differential expression of these proteins reflects the overall change in cellular structure and metabolism after insecticide treatment. 相似文献
953.
Trincao J Johnson RE Wolfle WT Escalante CR Prakash S Prakash L Aggarwal AK 《Nature structural & molecular biology》2004,11(5):457-462
The ability or inability of a DNA polymerase to extend a mispair directly affects the establishment of genomic mutations. We report here kinetic analyses of the ability of Dpo4, a Y-family polymerase from Sulfolobus solfataricus, to extend from all mispairs opposite a template G or T. Dpo4 is equally inefficient at extending these mispairs, which include, surprisingly, a G.T mispair expected to conform closely to Watson-Crick geometry. To elucidate the basis of this, we solved the structure of Dpo4 bound to G.T-mispaired primer template in the presence of an incoming nucleotide. As a control, we also determined the structure of Dpo4 bound to a matched A-T base pair at the primer terminus. The structures offer a basis for the low efficiency of Dpo4 in extending a G.T mispair: a reverse wobble that deflects the primer 3'-OH away from the incoming nucleotide. 相似文献
954.
Chemical modification of rubber wood (Hevea Brasiliensis) was carried out by impregnating the wood with styrene and in combination with a crosslinker Glycidyl Methacrylate (GMA). Polymerization was carried out by catalyst heat treatment. The dimensional stability in terms of % volumetric swelling and anti-shrink efficiency was determined and found to be improved on treatment. Water absorption was also found to be decreased considerably for treated wood samples. Mechanical strength of the treated samples in terms of modulus of rupture and modulus of elasticity were also found to be improved. The wood polymer interaction was confirmed by FT-IR spectroscopy. Biodegradability of the wood/polymer composites was determined and found to be improved on treatment with styrene/styrene-GMA. 相似文献
955.
956.
Plants of Ipomoea genus are widely distributed in India as wild vegetation and are reported source for the seed gums. Seed gums from Ipomoea dasysperma, Ipomoea hederacea, and Ipomoea palmata plants were grafted with polyacrylonitrile (PAN) using potassium persulfate/ascorbic acid redox initiator for modifying their properties for potential industrial applications. Under identical grafting conditions, the extent of the grafting was observed to be dependent on the galactose-to-mannose ratio and the degree of the branching in the galactomannans. Viscosity, gel formation, film formation, and the shelf life of the grafted gum solutions and water and saline retention capacity of the grafted seed gums were determined and compared with the parent gums. Water retention of the alkalie hydrolyzed grafted seed gums were also studied. Grafted gums were characterized using FTIR, NMR, and XRD analysis. 相似文献
957.
beta-Glucuronidase from bovine liver is able to catalyze transfer of several carbohydrates to furfuryl alcohol, an acid-sensitive diene, with transfer yields as high as 84%. Carbohydrates that were transferred in yields of 30% or higher include gluco-, galacto-, xylo-, and fucopyranose. Small variations in the configuration of the substrate hydroxyls lead to large variations in the catalytic behavior of the enzyme in terms of both the initial reaction velocities and the final ratios of transfer-to-hydrolysis. The high transfer yields and surprising nonspecificity towards carbohydrate suggest that the enzyme may be a versatile tool for the general O-glycosylation of dienic alcohols. 相似文献
958.
Identification of mtDNA mutation in a pedigree with gestational diabetes, deafness, Wolff-Parkinson-White syndrome and placenta accreta 总被引:2,自引:0,他引:2
Aggarwal P Gill-Randall R Wheatley T Buchalter MB Metcalfe J Alcolado JC 《Human heredity》2001,51(1-2):114-116
Mitochondrial DNA (mtDNA) defects are associated with a number of human disorders. Although many occur sporadically, maternal transmission is the hallmark of diseases due to mtDNA point mutations. The same mutation may manifest strikingly different phenotypes; for example, the A to G substitution at np 3243 was first reported in patients with mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (the MELAS syndrome), but is also found in patients with diabetes and deafness. Here we present a case of gestational diabetes, deafness, premature greying, placenta accreta and Wolff-Parkinson-White (WPW) syndrome associated with a mtDNA mutation. Although this is the first report of such an association, study of 27 other patients with WPW syndrome failed to confirm that this mtDNA mutation is a common cause of such pre-excitation disorders. 相似文献
959.
960.