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851.
Zhaoning Zhu Zhong-Yue Sun Yuanzan Ye Brian McKittrick William Greenlee Michael Czarniecki Ahmad Fawzi Hongtao Zhang Jean E. Lachowicz 《Bioorganic & medicinal chemistry letters》2009,19(17):5218-5221
A series of novel 1,3-benzodiazapine based D1 antagonists was designed according to the understanding of pharmacophore models derived from SCH 23390 (1b), a potent and selective D1 antagonist. The new design features an achiral cyclic-amidine that maintains desired basicity. Solid phase synthesis was developed for SAR development of the novel dopamine antagonists. 相似文献
852.
John P. Caldwell Julius J. Matasi Xiomara Fernandez Robbie L. McLeod Hongtao Zhang Ahmad Fawzi Deen B. Tulshian 《Bioorganic & medicinal chemistry letters》2009,19(4):1164-1167
A series of N-8 substituted analogs based upon the spiropiperidine core of the original lead compound 1 was synthesized. This lead has been elaborated to compounds to give compounds 2 and 3 (R = H) that exhibited high NOP binding affinity as well as selectivity against other known opioid receptors. These two series have been further functionalized at the amido nitrogen. The synthesis and structure–activity relationship (SAR) of these and related compounds are discussed. 相似文献
853.
The objectives of present study were (a) validation of annexin V/PI assay for estimation of sperm apoptosis in buffalo (Experiment 1) and (b) determining the effect of stages of cryopreservation on sperm apoptosis and its correlation with sperm motility and plasma membrane integrity (Experiment 2). In Experiment 1, different levels of apoptosis were artificially induced in buffalo semen (100 × 106 sperm/aliquot) through graded doses of camptothecin (5, 10 and 20 μM/aliquot). Higher concentrations of camptothecin (10 and 20 μM) successfully (P < 0.05) induced apoptosis as compared to the lower (5 μM) dose and/or control. In Experiment 2, semen samples (n = 9, three pooled semen samples from each of the three buffalo bulls separately) were cryopreserved using vapor freezing. The mean percentage of apoptotic, necrotic and viable sperm did not differ between fresh and before freezing stages. However, freezing and thawing increased (P < 0.05) the percentage of apoptotic sperm (25.4 ± 0.6 vs. 36.5 ± 1.9) while decreased (P < 0.05) the necrotic (35.1 ± 1.2 vs. 29.7 ± 0.7) and viable sperm (37.2 ± 1.3 vs. 32.8 ± 1.9, (P < 0.07). Likewise, the mean percent motility and plasma membrane integrity decreased (P < 0.05) (64 ± 2.1 vs. 49.4 ± 1.3) and (79.6 ± 0.5 vs. 38.7 ± 0.3) respectively, at post thaw compared to other stages. Coefficient of correlation, combined at all stages for each variable revealed that sperm apoptosis was inversely correlated with sperm motility and plasma membrane integrity. It is concluded that (a) the annexin V/PI assay can be used as a tool to determine the buffalo semen apoptosis and (b) freezing and thawing induces apoptosis in buffalo sperm. 相似文献
854.
Muhammad Sajid Aqeel Ahmad Qasim Ali Muhammad Ashraf Muhammad Zulqarnain Haider Qaswar Abbas 《Environmental and Experimental Botany》2009,66(3):409-417
A hydroponic experiment was conducted to assess the possible involvement of polyamines (PAs), abscisic acid (ABA) and anti-oxidative enzymes such as superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) in adaptation of six populations of Panicum antidotale Retz. to selection pressure (soil salinity) of a wide range of habitats. Plants of six populations were collected from six different habitats with ECe ranging from 3.39 to 19.23 dS m−1 and pH from 7.65 to 5.86. Young tillers from 6-month-old plants were transplanted in plastic containers each containing 10 l of half strength Hoagland's nutrient solution alone or with 150 mol m−3 NaCl. After 42 days growth, contents of polyamines (Put, Spd and Spm) and ABA, and the activities of anti-oxidative enzymes (SOD, POD and CAT) of all populations generally increased under salt stress. The populations collected from highly saline habitats showed a greater accumulation of polyamines and ABA and the activities of anti-oxidative enzymes as compared to those from mild or non-saline habitats. Moreover, Spm/Spd and Put/(Spd + Spm) ratios generally increased under salt stress. However, the populations from highly saline environments had significantly higher Spm/Spd and Put/(Spd + Spm) ratios as compared to those from mild or non-saline environments. Similarly, the populations adapted to high salinity accumulated less Na+ and Cl− in culm and leaves, and showed less decrease in leaf K+ and Ca2+ under salinity stress. Higher activities of anti-oxidative enzymes and accumulation of polyamines and ABA, and increased Spm/Spd and Put/(Spm + Spd) ratios were found to be highly correlated with the degree of adaptability of Panicum to saline environment. 相似文献
855.
Héctor M. Conesa Ahmad B. Moradi Brett H. Robinson Guido Kühne Eberhard Lehmann Rainer Schulin 《Environmental and Experimental Botany》2009,65(2-3):198-204
Mine tailings are an environmental problem in Southern Spain because wind and water erosion of bare surfaces results in the dispersal of toxic metals over nearby urban or agricultural areas. Revegetation with tolerant native species may reduce this risk. We grew two grasses, Lygeum spartum and Piptatherum miliaceum, and the crop species Cicer arietinum (chickpea) under controlled conditions in pots containing a mine tailings mixed into non-polluted soil to give treatments of 0%, 25%, 50%, 75% and 100% mine tailings. We tested a neutral (pH 7.4) mine tailings which contained high concentrations of Cd, Cu, Pb and Zn. Water-extractable metal concentrations increased in proportion to the amount of tailings added. The biomass of the two grasses decreased in proportion to the rate of neutral mine-tailing addition, while the biomass of C. arietinum only decreased in relation to the control treatment. Neutron radiography revealed that root development of C. arietinum was perturbed in soil amended with the neutral tailings compared to those of the control treatment, despite a lack of toxicity symptoms in the shoots. In all treatments and for all metals, the plants accumulated higher concentrations in the roots than in shoots. The highest concentrations occurred in the roots of P. miliaceum (2500 mg kg?1 Pb, 146 mg kg?1 Cd, 185 mg kg?1 Cu, 2700 mg kg?1 Zn). C. arietinum seeds had normal concentrations of Zn (70–90 mg kg?1) and Cu (6–9 mg kg?1). However, the Cd concentration in this species was ~1 mg kg?1 in the seeds and 14.5 mg kg?1 in shoots. Consumption of these plant species by cattle and wild fauna may present a risk of toxic metals entering the food chain. 相似文献
856.
Jay Epstein Rainer Seitz Neelam Dhingra Peter R. Ganz Ahmad Gharehbaghian Renato Spindel Diana Teo Ravi Reddy 《Biologicals》2009,37(2):94-102
In this paper the authors discuss the role of regulation in assuring blood safety. After an overview of the subject by a leading expert, examples are provided of regulatory systems for blood transfusion services in several countries and regions. Additionally, the perspective of WHO is given on the essential role of national regulatory authorities in assuring the quality of national blood programmes.Collectively, the sections of this paper afford an opportunity for readers to make comparisons among different regulatory frameworks and to "benchmark" among the existing systems. Despite many differences in approach, a clear pattern emerges of worldwide efforts to strengthen blood regulatory systems. 相似文献
857.
Stem cell capability enhanced with cytokine administration is a promising treatment for myocardial infarction. Bone marrow stem cells (BMSCs) were isolated from C57BL/6 mice (8-12 weeks old) expressing GFP and characterized with c-kit and CD34. Infarcted heart tissue fragments were placed into dishes with BMSCs and medium supplemented with G-CSF, SCF, IGF-1 or combinations thereof were given to the BMSC-infarcted myocardium in vitro model. The IGF-1-G-CSF group showed significantly higher migration (67.7% ± 2.6) of c-kit+ BMSCs towards the ischemic tissue and expressed MEF-2 (43.7% ± 1.7). Of the single treatment groups, the G-CSF group demonstrated significantly higher migration of c-kit+ BMSCs (60.5 ± 2.7) with MEF-2 expression (38.7 ± 1.4). IGF-1 complements G-CSF and was relatively more significant in its effects on BMSC migration and cardiac lineage commitment towards ischemic heart tissue. 相似文献
858.
859.
Ahmed Kamal M. Shaheer Malik Ahmad Ali Shaik Shaik Azeeza 《Journal of Molecular Catalysis .B, Enzymatic》2009,58(1-4):132-137
A simple and efficient method for the synthesis of optically active γ-azidoalcohols is described. The lipase catalyzed kinetic resolutions of acetates of γ-azidoalcohols in aqueous as well as organic media have been studied. The enantiomerically pure γ-azidoalcohols obtained by the kinetic resolution in high enantiopurity have been utilized towards the synthesis of enantiomeric pairs of anti-depressant drugs, fluoxetine and duloxetine. 相似文献
860.