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排序方式: 共有444条查询结果,搜索用时 15 毫秒
41.
Pandey GN Dwivedi Y Ren X Rizavi HS Faludi G Sarosi A Palkovits M 《Neurochemical research》2006,31(2):167-176
Abnormalities in serotonin receptor subtypes have been observed in the postmortem brain of suicide victims. We examined the regional distribution of serotonin (5HT)(2C) receptor mRNA in several areas of the human brain and also compared its protein and mRNA expression in the prefrontal cortex (PFC), hippocampus, and choroid plexus between suicide victims and normal control subjects. 5HT(2C) receptors were found to be distributed in several areas of the human brain (in order of abundance): highly concentrated and richest in choroid plexus; hypothalamus; nucleus accumbens; with the lowest abundance in PFC and cerebellum. Comparison of 5HT(2C) receptors between suicide victims and control subjects showed higher protein levels in the PFC but not the hippocampus or choroid plexus of suicide victims. However, there were no significant differences in mRNA levels between suicide victims and control subjects in these brain areas. These results suggest that 5HT(2C) receptors are richly distributed throughout the brain with the highest level in the choroid plexus and that abnormalities in protein expression of 5HT(2C) receptors in the PFC may be associated with suicide. 相似文献
42.
DBU catalyzed condensation of 3-O-benzyl(methyl)-5,6-dideoxy-1,2-O-isopropylidene-beta-L-threo-hept-4-enofuranuronates with different aldehydes produces the corresponding 3-O-benzyl(methyl)-6-carbethoxy-5,6-dideoxy-1,2-O-isopropylidene-7-phenyl-beta-L-threo-hept-4-enofuranoses. The latter on treatment with methanesulfonyl chloride followed by DBU catalyzed E2 reaction of the methanesulfonyloxy intermediates gave the respective 3-O-benzyl(methyl)-6-carbethoxy-5,6,7-trideoxy-1,2-O-isopropylidene-7-phenyl-beta-L-threo-hept-4,6-dienofuranose in moderate to good yields. 相似文献
43.
Dwivedi VP Tousif S Bhattacharya D Prasad DV Van Kaer L Das J Das G 《The Journal of biological chemistry》2012,287(5):2943-2947
TGF-β is a pleiotropic cytokine that predominantly exerts inhibitory functions in the immune system. Unexpectedly, the in vitro differentiation of both Th17 and Tc17 cells requires TGF-β. However, animals that are impaired in TGF-β signaling (TGF-βRIIDN mice) display multiorgan autoimmune disorders. Here we show that CD4(+) T cells from TGF-βRIIDN mice are resistant to Th17 cell differentiation and, paradoxically, that CD8(+) T cells from these animals spontaneously acquire an IL-17-producing phenotype. Neutralization of IL-17 or depletion of CD8(+) T cells dramatically inhibited inflammation in TGF-βRIIDN mice. Therefore, the absence of TGF-β triggers spontaneous differentiation of IL-17-producing CD8(+) T cells, suggesting that the in vivo and in vitro conditions that promote the differentiation of IL-17-producing CD8(+) T cells are distinct. 相似文献
44.
RR Pandey A Srivastava R Malasoni A Naqvi A Jain JP Maikhuri S Paliwal G Gupta AK Dwivedi 《Bioorganic & medicinal chemistry letters》2012,22(17):5735-5738
A series of twenty two derivatives of 3-(1-alkyl/aminoalkyl-3-vinyl-piperidin-4-yl)-1-(quinolin-4-yl)-propan-1-one and their 2-methylene derivatives were synthesized from naturally abundant cinchonine (I). Tartarate salts of these compounds were prepared and evaluated for spermicidal activity. The most active compounds (24, 27, 34, 36, and 38) showing potent spermicidal activity were further evaluated against different strains of Trichomonas vaginalis, for antimicrobial activity, in HeLa cell lines for cytotoxicity and against Lactobacillus jensenii for eco-safety. The tartarate of 3-(1-pentyl-3-vinyl-piperidin-4-yl)-1-(quinolin-4-yl)-propan-1-one (27) was found to be more active than N-9 in spermicidal activity. 相似文献
45.
This study estimates global warming impact (GWI) of E85 fuel needed to run a small passenger car for its average lifetime, i.e., 241,402 km (150,000 miles). The ethanol needed for the production of E85 fuel was derived from an intensively managed slash pine (Pinus elliottii) plantation in the southern USA. We assumed that only pulpwood and harvesting residues obtained at the time of harvesting were used for ethanol production. A suitable system boundary was defined and a detailed life-cycle assessment was undertaken to determine GWI of all the steps present within the system boundary. Results indicate that the overall GWI of the E85 fuel was about 76% less than an equivalent amount of gasoline needed to run a small passenger car for its average lifetime. Within the system boundary, the GWI of the ethanol production stage was highest followed by the stage of E85 fuel consumption in a small passenger car. A need exists to evaluate impacts of utilizing forest biomass for E85 fuel production on forest ecology and traditional forest biomass-based industries. 相似文献
46.
Genetically modified (GM) mustard line (V4) with increased carotenoid content was compared with native mustard to find the difference in allergenic potential, if any. Simulated gastric fluid (SGF) digestibility of crude protein extract from GM as well as its native counterpart mustard crop was envisaged to understand the intended or unintended changes in GM crop along with IgE immunoblotting. BALB/c mice were used as model for allergenicity studies for monitoring total and specific IgE, specific IgG1, histamine level, histopathology, and systemic anaphylaxis score. Allergenicity of mustard was checked in humans by clinical history, skin prick test and IgE levels. Similar results were evident by significant increase in total IgE, specific IgE, IgG1, histamine levels, in GM and native mustard in comparison to control group. Prominent anaphylactic symptoms (score 2: 60%; score 3: 20%; score 4: 20% in native mustard and score 2: 40%; score 3: 40%; score 4: 20% in GM mustard) and eruptive histopathological changes were observed in both GM and native mustard when compared with controls. One protein of approximately 16 kDa was found stable up to 1 h in both GM as well as non GM mustard. IgE immunoblotting detected three protein components of approximately 29, 24 and 16 kDa in both GM and non GM varieties. Collectively, our data demonstrate substantially equivalent allergic responses against GM as well as its native counterpart. Therefore, the GM mustard may be as safe as its native counterpart with reference to allergenic responses. 相似文献
47.
48.
Xianqiang Song Jun Yang Jamila Hirbawi Sheng Ye H Dhanuja Perera Esen Goksoy Pallavi Dwivedi Edward F Plow Rongguang Zhang Jun Qin 《Cell research》2012,22(11):1533-1545
The activation of heterodimeric (α/β) integrin transmembrane receptors by
cytosolic protein talin is crucial for regulating diverse cell-adhesion-dependent
processes, including blood coagulation, tissue remodeling, and cancer metastasis. This
process is triggered by the coincident binding of N-terminal FERM
(four-point-one-protein/ezrin/radixin/moesin) domain of talin (talin-FERM) to the inner
membrane surface and integrin β cytoplasmic tail, but how these binding events are
spatiotemporally regulated remains obscure. Here we report the crystal structure of a
dormant talin, revealing how a C-terminal talin rod segment (talin-RS) self-masks a key
integrin-binding site on talin-FERM via a large interface. Unexpectedly, the structure
also reveals a distinct negatively charged surface on talin-RS that electrostatically
hinders the talin-FERM binding to the membrane. Such a dual inhibitory topology for talin
is consistent with the biochemical and functional data, but differs significantly from a
previous model. We show that upon enrichment with phosphotidylinositol-4,5-bisphosphate
(PIP2) – a known talin activator, membrane strongly attracts a positively charged
surface on talin-FERM and simultaneously repels the negatively charged surface on
talin-RS. Such an electrostatic “pull-push” process promotes the relief of the
dual inhibition of talin-FERM, which differs from the classic “steric clash”
model for conventional PIP2-induced FERM domain activation. These data therefore unravel a
new type of membrane-dependent FERM domain regulation and illustrate how it mediates the
talin on/off switches to regulate integrin transmembrane signaling and cell adhesion. 相似文献
49.
Dwivedi AP Kumar S Varshney V Singh AB Srivastava AK Sahu DP 《Bioorganic & medicinal chemistry letters》2008,18(7):2301-2305
A series of novel N-acyl-2-arylethylamines and N-acyl-3-coumarylamines were synthesized and evaluated for their antihyperglycemic activity. Compounds 3g and 6d exhibited lowering of postprandial plasma glucose by 30.7%, 23.3% in SLM and 25.6%, 25.4% in STZ models respectively which is significant compared to metformin and glybenclamide. Other compounds exhibited moderate to good activity ranging from 19.5% to 32.8% in SLM and 3.26% to 25.4% in STZ models. 相似文献
50.
Thangaraj K Chaubey G Kivisild T Selvi Rani D Singh VK Ismail T Carvalho-Silva D Metspalu M Bhaskar LV Reddy AG Chandra S Pande V Prathap Naidu B Adarsh N Verma A Jyothi IA Mallick CB Shrivastava N Devasena R Kumari B Singh AK Dwivedi SK Singh S Rao G Gupta P Sonvane V Kumari K Basha A Bhargavi KR Lalremruata A Gupta AK Kaur G Reddy KK Rao AP Villems R Tyler-Smith C Singh L 《Human heredity》2008,66(1):1-9
We have analyzed 7,137 samples from 125 different caste, tribal and religious groups of India and 99 samples from three populations of Nepal for the length variation in the COII/tRNA(Lys) region of mtDNA. Samples showing length variation were subjected to detailed phylogenetic analysis based on HVS-I and informative coding region sequence variation. The overall frequencies of the 9-bp deletion and insertion variants in South Asia were 1.9 and 0.6%, respectively. We have also defined a novel deep-rooting haplogroup M43 and identified the rare haplogroup H14 in Indian populations carrying the 9-bp deletion by complete mtDNA sequencing. Moreover, we redefined haplogroup M6 and dissected it into two well-defined subclades. The presence of haplogroups F1 and B5a in Uttar Pradesh suggests minor maternal contribution from Southeast Asia to Northern India. The occurrence of haplogroup F1 in the Nepalese sample implies that Nepal might have served as a bridge for the flow of eastern lineages to India. The presence of R6 in the Nepalese, on the other hand, suggests that the gene flow between India and Nepal has been reciprocal. 相似文献