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991.
Kumar A Tripathi VD Kumar P Gupta LP Akanksha Trivedi R Bid H Nayak VL Siddiqui JA Chakravarti B Saxena R Dwivedi A Siddiquee MI Siddiqui U Konwar R Chattopadhyay N 《Bioorganic & medicinal chemistry》2011,19(18):5409-5419
A new series of 1,3-biarylsulfanyl derivatives (homodibenzyl core motif) have been designed and synthesized as new estrogen receptor ligands by chopping benzothiophene core of raloxifene to engender seco-raloxifene scaffold. All the synthesized compounds were screened for anti-proliferative, anti-osteoporotic, and anti-implantation activity. Compounds (35, 36) having basic amino anti-estrogenic side chain were exhibiting potential anti-proliferative activity in MCF-7, MDA-MB-231 and ishikawa cell lines. Some of the synthesized compounds having homodibenzyl motif (5, 8, 10) have shown moderate anti-osteoporotic activity. 相似文献
992.
Chi Y Fan Y He L Liu W Wen X Zhou S Wang X Zhang C Kong H Sonoda L Tripathi P Li CJ Yu MS Su C Hu G 《Aging cell》2011,10(3):368-382
Aquaporin-4 (AQP4) is highly expressed in mammalian brains and is involved in the pathophysiology of cerebral disorders, including stroke, tumors, infections, hydrocephalus, epilepsy, and traumatic brain injury. We found that AQP4-deficient mice were hypersensitive to stimulations such as 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) or lipopolysaccharide compared to wild-type (WT) littermates. In a mouse model of MPTP-induced Parkinson's disease (PD), AQP4-deficient animals show more robust microglial inflammatory responses and more severe loss of dopaminergic neurons (DNs) compared with WT mice. However, a few studies have investigated the association of abnormal AQP4 levels with immune dysfunction. Here, for the first time, we report AQP4 expression in mouse thymus, spleen, and lymph nodes. Furthermore, the significantly lower numbers of CD4(+) CD25(+) regulatory T cells in AQP4-deficient mice compared to WT mice, perhaps resulting from impaired thymic generation, may be responsible for the uncontrolled microglial inflammatory responses and subsequent severe loss of DNs in the substantia nigra pars compacta in the MPTP-induced PD model. These novel findings suggest that AQP4 deficiency may disrupt immunosuppressive regulators, resulting in hyperactive immune responses and potentially contributing to the increased severity of PD or other immune-associated diseases. 相似文献
993.
Trivendra Tripathi Mohammad Shahid Haris M. Khan Rahat Ali Khan Mashiatullah Siddiqui Abbas Ali Mahdi 《Saudi Journal of Biological Sciences》2011,18(4):411-418
This study was designed to investigate the functional roles of histamine and histamine H1-receptor agonist and antagonist in the development of liver function impairment in immunized rabbits. The study comprised of six groups containing 18 rabbits each. Group III–VI received histamine (100 μg/kg, s.c.), H1R-agonist (HTMT, 10 μg/kg, s.c.), H1R-antagonist (pheniramine, 10 mg/kg, i.m.), and H1R-antagonist (pheniramine, 10 mg/kg, i.m.) plus histamine (100 μg/kg, s.c.), respectively, b.i.d. for 10 days. Group I (negative control) and group II (positive control) received sterile distilled water intramuscularly b.i.d. for 10 days. Groups II–VI were immunized on day 3 with intravenous injection of SRBC (1 × 109 cells/ml). Blood samples were collected on pre-immunization day 0, as well as on days 7-, 14-, 21-, 28-, and 58-post-immunization. Biochemical parameters AST, ALT, alkaline phosphatase and bilirubin [total bilirubin (TB), direct bilirubin (DB), and indirect bilirubin (IB)] were determined. On each experimental day, the mean values of serum enzymes and bilirubin in group I and group II showed no significant changes while in group III, IV, V, and VI, these enzymes and bilirubin levels showed significant changes (p < 0.05), when compared with their experimental values within the group. The levels of serum enzymes and bilirubin showed significant difference (p < 0.05) in group III, IV, V, and VI on each experimental day, when compared with the corresponding values of each other, and also compared with the corresponding values of group I and II. Histamine, HTMT, pheniramine, and combination of histamine + pheniramine cause hepatic function impairment in terms of altered serum enzymes and bilirubin levels. The present findings suggest that HTMT causes moderate liver function impairment while others show mild impairment. 相似文献
994.
995.
A new isolate of Streptomyces sp. from soil of state Chhattisgarh (India) having broad spectrum antibacterial and antifungal activity was obtained. The active strain was identified as Streptomyces rimosus subsp. rimosus with accession number MTCC 10792 based on physiological, biochemical characteristics and 16S rRNA sequence homology studies. Antimicrobial compound produced by S. rimosus was tested against the drug resistance pathogens by the Bauer and Kirby method. The crude active metabolite was extracted using solvent n-butanol and purified by silica column chromatography and HPLC method. The physicochemical characteristics of the one purified compound viz. color, melting point, solubility, elemental analysis, ESIMS, IR, UV, 1HNMR, 13CNMR and chemical reactions have been investigated. Purified antimicrobial compound produced by S. rimosus MTCC 10792 at concentration 25 μg/mL showed antitubercular activity against Mycobacterium tuberculosis H37Rv, Mycobacterium tuberculosis H37R as well as broad activity against all tested bacterial and fungal pathogens. 相似文献
996.
Ram Niwas Vineeta Singh Rajbir Singh Divya Tripathi C. K. M. Tripathi 《World journal of microbiology & biotechnology》2013,29(11):2077-2085
Cholesterol oxidase production (COD) by a new isolate characterized as Streptomyces sp. was studied in different production media and fermentation conditions. Individual supplementation of 1 % maltose, lactose, sucrose, peptone, soybean meal and yeast extract enhanced COD production by 80–110 % in comparison to the basal production medium (2.4 U/ml). Supplementation of 0.05 % cholesterol (inducer) enhanced COD production by 150 %. COD was purified 14.3-fold and its molecular weight was found to be 62 kDa. Vmax (21.93 μM/min mg) and substrate affinity Km (101.3 μM) suggested high affinity of the COD for cholesterol. In presence of Ba2+ and Hg2+ the enzyme activity was inhibited while Cu2+ enhanced the activity nearly threefold. Relative activity of the enzyme was found maximum in triton X-100 whereas sodium dodecyl sulfate inactivated the enzyme. The enzyme activity was also inhibited by the thiol-reducing reagents like Dithiothreitol and β-mercaptoethanol. The COD showed moderate stability towards all organic solvents except acetone, benzene and chloroform. The activity increased in presence of isopropanol and ethanol. The enzyme was most active at pH 7 and 37 °C temperature. This organism is not reported to produce COD. 相似文献
997.
Nidhi Bharti Purvi Agrawal Bishal Misra Arpita Tripathi Rakshpal Singh Deepamala Maji 《Biocontrol Science and Technology》2013,23(2):239-244
Application of Thiosalicylic acid+Bacillus cereus; O-Acetylsalicylic acid+Pseudomonas fluorescens reduced root rot severity by 85 and 88% and enhanced root yields by 358 and 419%, respectively, against Fusarium solani induced root rot disease in Withania somnifera. Reduction in disease severity was correlated with defence-related enzymes peroxidase, polyphenol oxidase and phenyl ammonium lyase. 相似文献
998.
999.
R. D. Tripathi S. C. Tripathi S. N. Dixit 《Bioscience, biotechnology, and biochemistry》2013,77(10):2483-2485
Rubusoside, the β-D-glucosyl ester of 13-O-D-glucosyl-steviol which was isolated from leaves of Rubus suavissimus collected in China as the major sweet principle (yield: 5.4%), was subjected to α-1 4 transglucosylation with the cyclodextrin glucosyltransferase produced by Bacillus megaterium Strain No. 5 using soluble starch as a donor. A significant improvement in the quality of sweetness was observed for the crude reaction mixture, which was separated into mono-, di-, tri-, tetra-, penta-, and hexa-glucosylated products. All isomers of the mono- and di-glucosylated products were further separated. Evaluation of the sweetness of these products compared with stevioside, rebaudioside A, etc. disclosed that the ratio of the number of glucose units at the 13-hydroxyl group to that at 19-carboxyl group seems to have a significant relationship with the sweetness as well as the quality of taste for glucosides of this type. 相似文献
1000.
Md Akhlaqur Rahman Navaneet Chaturvedi Sukrat Sinha Paras Nath Pandey Dwijendra Kumar Gupta Shanthy Sundaram Ashutosh Tripathi 《Bioinformation》2013,9(12):639-644
This study focuses on Ultra Violet stress (UVS) gene product which is a UV stress induced protein from cyanobacteria,
Synechocystis PCC 6803. Three dimensional structural modeling of target UVS protein was carried out by homology modeling
method. 3F2I pdb from Nostoc sp. PCC 7120 was selected as a suitable template protein structure. Ultimately, the detection of active
binding regions was carried out for characterization of functional sites in modeled UV-B stress protein. The top five probable
ligand binding sites were predicted and the common binding residues between target and template protein was analyzed. It has
been validated for the first time that modeled UVS protein structure from Synechocystis PCC 6803 was structurally and functionally
similar to well characterized UVS protein of another cyanobacterial species, Nostoc sp PCC 7120 because of having same structural
motif and fold with similar protein topology and function. Investigations revealed that UVS protein from Synechocystis sp. might
play significant role during ultraviolet resistance. Thus, it could be a potential biological source for remediation for UV induced
stress. 相似文献