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281.
Pawandeep Kaur Jitendra Gaikwad Birgitta König-Ries 《Biodiversity and Conservation》2016,25(9):1801-1803
To address the critical challenges of biodiversity conservation and study its impact on the ecosystem, over the last decade, scientists have been producing a large amount of highly heterogeneous and distributed data. For managing, processing, and visualizing this data, requires informatics skills. While many biologists lack these skills, informaticians are limited in their understanding of biological domain requirements and the context of the data. The focus of our research study is to assist scientists with the suggestion of possible visualizations for exploring and understanding their data. To be useful, such suggestions need to be based on the visualization knowledge of domain experts. We intend to gather such knowledge and use in the development of a visualization recommendation framework serving the biodiversity research community. Therefore, the authors want to encourage readers to share their domain knowledge on the biodiversity data visualization usage by participating in an online survey. 相似文献
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Vijay K. Sharma Pradeep K. Jain Satish C. Maheshwari Jitendra P. Khurana 《Journal of plant biochemistry and biotechnology.》1995,4(2):91-95
Mitochondria isolated from 4-day-old dark-grown wheat seedlings were purified by self-generating Percoll gradient. Phosphorylation reaction was carried out in vitro with the addition of [ c-32P]ATP and polypeptides resolved by 50S-PAGE were subjected to autoradiography. Amongst endogenous polypeptides phosphorylated, four polypeptides of 120, 66, 43 and 21 kD were prominent. Addition of Mg2+ (5 mM) caused dephosphorylation of 120 and 66 kO polypeptides but, simultaneously, induced/enhanced the phosphorylation of some polypeptides, with the effect being more pronounced on a 67 kD species. The phosphorylation of 120 kD species and a few other polypeptides was also down-regulated and that of a 18 kD polypeptide was up-regulated by Ca2+. The present study provides evidence that phosphorylation status of mitochondrial proteins is regulated by Mg2+ and/or Ca2+-dependent phosphatase(s) and protein kinase(s). 相似文献
284.
The objectives of this study were to determine (i) if the age-related changes in 125I-labeled ovine prolactin specific binding of rat ventral prostate was correlated with changes in membrane lipid microviscosity and (ii) if membrane fluidizers produced age-dependent effects on prolactin binding of prostatic membranes. The degree of fluidization was monitored by a fluorescence polarization method using 1,6-diphenylhexatriene. Membrane preparations of ventral prostate glands obtained from immature (24–25 days old), young-adult (80–90 days old) and aged (550–610 days old) male rats were used for prolactin binding and membrane lipid microviscosity measurements. Relative to immature rats, prostatic prolactin binding decreased approximately 50% in young-adult rats and 75% in aged rats. Membrane lipid microviscosity, relative to immature rats, was increased 72% in young-adult rats and 140% in aged rats. Prostatic membranes obtained from immature animals exhibited no significant effects of in vitro alcohol treatment on prolactin binding, whereas, those obtained from aged animals exhibited maximal increase in prolactin binding. The value of the microviscosity parameter, after in vitro alcohol exposure, exhibited no significant changes in immature animals, whereas, this parameter was decreased approximately 15% in young-adults and approximately 30% in aged animals. These data suggest that in vitro fluidization of prostatic membrane exhibits an age-dependent modification of prolactin binding. 相似文献
285.
6,7-Dinitroquinoxaline-2,3-Dione Blocks the Cytotoxicity of N-Methyl-D-Aspartate and Kainate, but Not Quisqualate, in Cortical Cultures 总被引:1,自引:0,他引:1
Jitendra Patel William C. Zinkand rea B. Klika Thomas J. Mangano Richard A. Keith re I. Salama 《Journal of neurochemistry》1990,55(1):114-121
Based on radioligand binding and electrophysiological studies, quinoxalinediones such as 6,7-dinitroquinoxaline-2,3-dione (DNQX) have been shown to be potent competitive antagonists at the quisqualate and kainate subtypes of the glutamate receptor. In this report we have examined the effects of DNQX on excitatory amino acid neurotoxicity and evoked neurotransmitter release. DNQX was found to be a potent neuroprotective agent against glutamate and N-methyl-D-aspartate (NMDA) neurotoxicity. The data suggest that this neuroprotective activity of DNQX is due to its antagonism of the coagonist activity of glycine at the NMDA receptor-channel complex. The specificity of DNQX for the glycine site associated with the NMDA receptor-channel complex was confirmed in radioligand binding and neurotransmitter release studies. DNQX also prevented kainate neurotoxicity and kainate-evoked neurotransmitter release, presumably by direct competition for the kainate receptor. DNQX, however, did not prevent quisqualate neurotoxicity, suggesting that a novel quisqualate-preferring receptor insensitive to DNQX may mediate quisqualate toxicity. 相似文献
286.
Jitendra Patel William C. Zinkand Carolann Thompson Richard Keith re Salama 《Journal of neurochemistry》1990,54(3):849-854
Current evidence indicates that glutamate acting via the N-methyl-D-aspartate (NMDA) receptor/ion channel complex plays a major role in the neuronal degeneration associated with a variety of neurological disorders. In this report the role of glycine in NMDA neurotoxicity was examined. We demonstrate that NMDA-mediated neurotoxicity is markedly potentiated by glycine and other amino acids, e.g., D-serine. Putative glycine antagonists HA-966 and 7-chlorokynurenic acid were highly effective in preventing NMDA neurotoxicity, even in the absence of added glycine. The neuroprotective action of HA-966 and 7-chlorokynurenic acid, but not that of NMDA antagonists 3-(2-carboxypiperazine-4-yl)propylphosphonate and MK-801, could be reversed by glycine. These results indicate that glycine, operating through a strychinine-insensitive glycine site, plays a central permissive role in NMDA-mediated neurotoxicity. 相似文献
287.
Asher M. Siddiqui Jitendra A. Sattigeri Kalim Javed Syed Shafi M. Shamim Smita Singhal Zubbair M. Malik 《Bioorganic & medicinal chemistry letters》2018,28(7):1198-1206
Gram-positive bacteria are among the most common human pathogens associated with clinical infections which range from mild skin infections to sepsis. Resistance towards existing class of drugs by Gram-positive bacteria including methicillin resistant Staphylococcus aureus (MRSA), Staphylococcus epidermidis (MRSE) and vancomycin resistant enterococci (VRE) is a growing concern. There is an urgent need to discover new antibiotics which are active against resistant strains of Gram positive bacteria. We report herein a novel class of spiropyrimidinetrione oxazolidinone derivatives as novel antibacterial agents. Key step towards the synthesis of title compounds involved the use of tert-amino reaction with [1,5]-hydride shift leading to the new CC bond formation. Compound 30n has demonstrated potent antibacterial activity against a panel of Gram-positive microbial strains including MRSA, MRSE, and LNZ and vancomycin resistant strains of E. faecalis. Further, molecular docking studies suggest that 30n has binding mode similar to that of LNZ in 50S RNA ribosome. 相似文献
288.
Highly Efficient Oxygen Reduction Reaction Activity of Graphitic Tube Encapsulating Nitrided CoxFey Alloy 下载免费PDF全文
Siraj Sultan Jitendra N. Tiwari Jue‐Hyuk Jang Ahmad M. Harzandi Foad Salehnia Sung Jong Yoo Kwang S. Kim 《Liver Transplantation》2018,8(25)
Nonprecious metals are promising catalysts to avoid the sluggish oxygen reduction reaction (ORR) in next‐generation regenerative fuel cells or metal–air batteries. Therefore, development of nonprecious metal catalysts for ORR is highly desirable. Herein, precise tuning of the atomic ratio of Fe and Co encapsulated in melamine‐derived nitrogen‐rich graphitic tube (NGT) is reported. The Co1.08Fe3.34 hybrid with metal? nitrogen bonds ( 1 : Co1.08Fe3.34@NGT) shows remarkable ORR catalytic activities (80 mV higher in onset potential and 50 mV higher in half‐wave potential than those of state‐of‐the‐art commercial Pt/C catalysts), high current density, and stability. In acidic solution, 1 also shows compatible performance to commercial Pt/C in terms of ORR activity, current density, stability, and methanol tolerance. The high ORR activity is ascribed to the co‐existence of Fe? N, Co? N, and sufficient metallic FeCo alloys which favor faster electron movement and better adsorption of oxygen molecules on the catalyst surface. In the alkaline anion exchange membrane fuel cell setup, this cell delivers the power density of 117 mW cm?2, demonstrating its potential use for energy conversion and storage applications. 相似文献
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