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851.
Ali Nakhi Md. Shafiqur Rahman Ravada Kishore Chandana Lakshmi T. Meda Girdhar Singh Deora Kishore V.L. Parsa Manojit Pal 《Bioorganic & medicinal chemistry letters》2012,22(20):6433-6441
2-Substituted pyrrolo[2,3-b]quinoxalines having free NH were prepared directly from 3-alkynyl-2-chloroquinoxalines in a single pot by using readily available and inexpensive methane sulfonamide (or p-toluene sulfonamide) as an ammonia surrogate. The reaction proceeded in the presence of Cu(OAc)2 affording the desired product in moderate yield. The crystal structure analysis of a representative compound and its supramolecular interactions are presented. Some of the compounds synthesized exhibited inhibitory activities against luciferase that was supported by the predictive binding mode of these compounds with luciferase enzyme through molecular docking studies. The key observations disclosed here can alert users of luciferase reporter gene assays for possible false positive results due to the direct inhibition of luciferase. 相似文献
852.
P. Rama Chandra Prasad P. Mamtha Lakshmi K. S. Rajan Vijaya Bhole C. B. S. Dutt 《Biodiversity and Conservation》2012,21(2):309-322
Tropical islands are special and sensitive ecosystems which are subjected to various disturbances imposed by human activities and natural disasters. A detailed study about the changing landscape scenarios of these fragile island systems induced by various driving factors could be used for setting up measurements in support of conservation and sustainable development projects. The current research is a meta-analysis of the studies carried out in Andaman and Nicobar islands which analyzed the impact of tsunami of 2004 using geospatial tools. Based on the analysis, it was observed that the Nicobar islands were more affected compared to the Andaman islands. The majority of the researchers used pre- and post-tsunami satellite imagery and adopted visual interpretation method to delineate the changed classes. The study infers uplift of land in Andaman (exposing) and subsidence in Nicobar islands (inundation) with severe damage to the coastal elements like mangroves, coral reefs, plantations and in few cases interior forest. The analysis showed there were no records of the damage for some small islands. Finally, it is concluded that utility of microwave satellite data for change analysis will prove better in regions like Andaman and Nicobar where it is difficult to get cloud free optical data because of the high monsoon periods in these islands. It is also suggested that future work utilizing suitable temporal satellite imagery should focus on the extent of recovery of vegetation and other coastal elements which suffer the impact of disaster. 相似文献
853.
Thermosensitive genic male sterility (TGMS) in rice is a widely adopted technique for successful hybrid rice production in Asia. TGMS lines remain male sterile when daily mean temperature is above the critical sterility temperature and are therefore used as female parents. The same line will remain fertile when mean temperature is below the critical sterility temperature. Achievement of 100% male sterility in TGMS lines is important for the successful utilization of TGMS lines as female parents in hybrid rice production. This study examined the external application of some growth regulators and chemicals and their effect on pollen sterility. Among the various treatments, ethrel (800 ppm), salicylic acid (600 ppm) and maleic hydrazide (0.2%) induced a significantly higher percentage of male sterility in the TGMS lines. The sprayed plants also showed higher total phenol accumulation in their flag leaves. The results suggest that it is possible to achieve 100% male sterility in TGMS lines with the external application of growth regulators and chemicals. 相似文献
854.
Vijendra Prabhu Satish B. S. Rao Subhash Chandra Pramod Kumar Lakshmi Rao Vasudeva Guddattu Kapaettu Satyamoorthy Krishna K. Mahato 《Journal of biophotonics》2012,5(2):168-184
The present study focuses on the evaluation of the effect of He‐Ne laser on tissue regeneration by monitoring collagen synthesis in wound granulation tissues in Swiss albino mice using analysis of laser induced fluorescence (LIF) and light microscopy techniques. The spectral analyses of the wound granulation tissues have indicated a dose dependent increase in collagen levels during the post‐wounding days. The histological examinations on the other hand have also shown a significant increase in collagen deposition along with the reduced edema, leukocytes, increased granulation tissue, and fibroblast number in the optimal laser dose treated group compared to the non‐illuminated controls. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
855.
Ricardo Salomon-Torres Lakshmi K. Matukumalli Curtis P. Van Tassell Carlos Villa-Angulo Víctor M. Gonzalez-Vizcarra Rafael Villa-Angulo 《PloS one》2014,9(7)
Genomic structural variations represent an important source of genetic variation in mammal genomes, thus, they are commonly related to phenotypic expressions. In this work, ∼770,000 single nucleotide polymorphism genotypes from 506 animals from 19 cattle breeds were analyzed. A simple LD-based structural variation was defined, and a genome-wide analysis was performed. After applying some quality control filters, for each breed and each chromosome we calculated the linkage disequilibrium (r2) of short range (≤100 Kb). We sorted SNP pairs by distance and obtained a set of LD means (called the expected means) using bins of 5 Kb. We identified 15,246 segments of at least 1 Kb, among the 19 breeds, consisting of sets of at least 3 adjacent SNPs so that, for each SNP, r2 within its neighbors in a 100 Kb range, to the right side of that SNP, were all bigger than, or all smaller than, the corresponding expected mean, and their P-value were significant after a Benjamini-Hochberg multiple testing correction. In addition, to account just for homogeneously distributed regions we considered only SNPs having at least 15 SNP neighbors within 100 Kb. We defined such segments as structural variations. By grouping all variations across all animals in the sample we defined 9,146 regions, involving a total of 53,137 SNPs; representing the 6.40% (160.98 Mb) from the bovine genome. The identified structural variations covered 3,109 genes. Clustering analysis showed the relatedness of breeds given the geographic region in which they are evolving. In summary, we present an analysis of structural variations based on the deviation of the expected short range LD between SNPs in the bovine genome. With an intuitive and simple definition based only on SNPs data it was possible to discern closeness of breeds due to grouping by geographic region in which they are evolving. 相似文献
856.
Charlton JJ Allen PB Psifogeorgou K Chakravarty S Gomes I Neve RL Devi LA Greengard P Nestler EJ Zachariou V 《Neuron》2008,58(2):238-247
Spinophilin, a dendritic spine-enriched scaffold protein, modulates synaptic transmission via multiple functions mediated by distinct domains of the protein. Here, we show that spinophilin is a key modulator of opiate action. Knockout of the spinophilin gene causes reduced sensitivity to the analgesic effects of morphine and early development of tolerance but a higher degree of physical dependence and increased sensitivity to the rewarding actions of the drug. At the cellular level, spinophilin associates with the mu opioid receptor (MOR) in striatum and modulates MOR signaling and endocytosis. Activation of MOR by opiate agonists such as fentanyl and morphine promotes these events, which feedback to suppress MOR responsiveness. Our findings support a potent physiological role of spinophilin in regulating MOR function and provide a potential new target for the treatment of opiate addiction. 相似文献
857.
Members of several metalloprotease families have been proposed to be involved in non-classical processing of neuroendocrine precursors. Among them, endothelin converting enzyme-2 (ECE-2) is a good candidate since it exhibits a neuroendocrine distribution, intracellular subcellular localization, and an acidic pH optimum. The enzyme is able to generate a number of biologically active peptides from peptide intermediates, suggesting an important role for this enzyme in the biosynthesis of regulatory peptides. These results are consistent with an important role for ECE-2 in the processing of regulatory peptides at non-classical sites. 相似文献
858.
Isaac Bekhor Lakshmi Anne Jung Kim Jean-Numa Lapeyre Roger Stambaugh 《Archives of biochemistry and biophysics》1974,161(1):11-19
Prefractionation of chromosomal proteins in 5 m urea with stepwise increase in NaCl molarity has been used to facilitate the examination of nonhistone chromosomal proteins isolated from various rabbit tissues. Electrophoretic analysis on polyacrylamide gels under denaturing conditions of the protein fractions derived from brain, liver, heart, and submandibular salivary gland chromatins displays reproducible compositional differences in nonhistone chromosomal proteins. The enzymatic removal of 48% of protein-bound phosphate with alkaline phosphatase does not significantly alter the electrophoretic mobility of these proteins. With the present technique, it is estimated that chromatin polypeptides (of average Mr 100,000) occurring in greater than 3 × 104 copies per genome can be detected. At this level of sensitivity, a significant fraction of total nonhistone chromosomal proteins manifests organ specificity. 相似文献
859.
Selection for citrate synthase deficiency in icd mutants of Escherichia coli. 总被引:7,自引:4,他引:3 下载免费PDF全文
Cultures of isocitrate dehydrogenase-deficient (icd) mutants were overgrown by double mutants (icd glt) lacking citrate synthase activity also. The icd mutants grew more slowly than wild-type cells or the double mutants because they accumulated an inhibitory metabolite (possibly citrate). Intracellular citrate levels were several hundred-fold higher in icd cells than in wild-type or icd glt cells. Final growth yields of the wild type and the icd mutant on limiting glucose were equivalent and greater than the growth yield of icd glt double mutants. The icd gene mapped between 60 and 74 min. icd mutants were resistant to nalidixic acid, but glt and icd glt mutants and wild-type cells were sensitive, indicating that resistance results from accumulation of isocitrate, citrate, or a derivative of these compounds. 相似文献
860.
The investigation of three Leucanthemum species afforded, in addition to known compounds, two new C17-acetylenes, a new isovalerate, two phenolic acetylenes, a C12-isobutylamide and a new farnesol derivative. Chrysanthemum ferulaceum contains deacetyllaurenobiolide (spiciformin) which is identical with a lactone from Inula britannica previously assumed to be a cis, cis-germacranolide. 相似文献