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1.
Shailesh Kumar Atma P. Dwivedi Vivek Kr. Kashyap A.K. Saxena A.K. Dwivedi Ranjana Srivastava Devi P. Sahu 《Bioorganic & medicinal chemistry letters》2013,23(8):2404-2407
Synthesis of a library of novel trans 6-methoxy-1,1-dimethyl-2-phenyl-3-aryl-2,3-dihydro-1H-inden-4-yloxy alkyl amines and their antimycobacterial activity against drug sensitive and multidrug resistant strains of Mycobacterium tuberculosis have been reported. All the new compounds in the series exhibited MIC between 1.56 and 6.25 μg/ml. Two compounds 1i and 1j with low MIC and low cytotoxicity showed significant reduction in CFU in infected mouse macrophages at 1× MIC concentration. The compound 1i inhibited the growth of M. tuberculosis in mice at 100 mg/kg dose with 1.35 log10 reduction of CFU in lungs tissue and was active against non-replicating Mycobacterium tuberculosis under anaerobic condition. 相似文献
2.
John A. Schneider Rakhi Dandona Shravani Pasupneti Vemu Lakshmi Chuanhong Liao Vijay Yeldandi Kenneth H. Mayer 《PloS one》2010,5(7)
Studies of HIV prevention interventions such as pre-exposure prophylaxis (PREP) and circumcision in India are limited. The present study sought to investigate Indian truck-drivers initial commitment to PREP and circumcision utilizing the AIDS Risk Reduction Model. Ninety truck-drivers completed an in-depth qualitative interview and provided a blood sample for HIV and HSV-2 testing. Truck-drivers exhibited low levels of initial commitment towards PREP and even lower for circumcision. However, potential leverage points for increasing commitment were realized in fear of infecting family rather than self, self-perceptions of risk, and for PREP focusing on cultural beliefs towards medication and physicians. Cost was a major barrier to both HIV prevention interventions. Despite these barriers, our findings suggest that the ARRM may be useful in identifying several leverage points that may be used by peers, health care providers and public health field workers to enhance initial commitment to novel HIV prevention interventions in India. 相似文献
3.
4.
Madeleine St Clair Yewers Devi Stuart‐Fox Claire Alice McLean 《Ecology and evolution》2019,9(1):295-306
Space use including territoriality and spatial arrangement within a population can reveal important information on the nature, dynamics, and evolutionary maintenance of alternative strategies in color polymorphic species. Despite the prevalence of color polymorphic species as model systems in evolutionary biology, the interaction between space use and genetic structuring of morphs within populations has rarely been examined. Here, we assess the spatial and genetic structure of male throat color morphs within a population of the tawny dragon lizard, Ctenophorus decresii. Male color morphs do not differ in morphology but differ in aggressive and antipredator behaviors as well as androgen levels. Despite these behavioral and endocrine differences, we find that color morphs do not differ in territory size, with their spatial arrangement being essentially random with respect to each other. There were no differences in genetic diversity or relatedness between morphs; however, there was significant, albeit weak, genetic differentiation between morphs, which was unrelated to geographic distance between individuals. Our results indicate potential weak barriers to gene flow between some morphs, potentially due to nonrandom pre‐ or postcopulatory mate choice or postzygotic genetic incompatibilities. However, space use, spatial structure, and nonrandom mating do not appear to be primary mechanisms maintaining color polymorphism in this system, highlighting the complexity and variation in alternative strategies associated with color polymorphism. 相似文献
5.
R. Sankar P. S. Devamanoharan G. Raghupathi M. Krishnasamy C. S. Shyamala Devi 《Journal of biosciences》1987,12(3):267-271
Plumbagin was administered to rats at a concentration of 1,2,4,8 and 16 mg per kg body weight. After 24 h lipid peroxide levels
were found to decrease in subcellular fractions of liver. Plumbagin inhibited ascorbate and nicotinafde adenine dinucleotide
phosphate (reduced) dependent lipid peroxidation but was without any effect on cumene hydroperoxide dependent lipid peroxidation.
Injection of 16 mg of plumbagin per kg body weight was found to decrease liver total reduced glutathione and also fcrosomal
glucose-6-phosphatase. The results are discussed with reference to the anti- and prooxidant properties of plumbagin. 相似文献
6.
A method has been developed for immobilisation of antisera on fresh plastic tubes through an immunochemical bridge. This type
of immobilisation has been shown to be more consistent than direct adsorption on plastic. Such immunochemically coated antisera
on plastic tube has been used in the development of a noncentrifugation radioimmunoassay. This assay system has been found
to be technically as sound as the conventional method. 相似文献
7.
Significant differences were observed in GAG metabolism of S. digitata and one of its intermediate vectors, C. quinquefasciatus. Distribution of different components such as hyaluronic acid, heparin-sulphate, chondroitin-4-sulphate, chondroitin-6-sulphate, dermatan sulphate and heparin was comparable in both. However, there were quantitative differences; the difference was marked in the activity of enzymes of GAG metabolism in presence and absence of diethylcarbamazine (DEC) a known antifilarial drug. While the activities of beta-galactosidase and beta-N-acetyl glucosaminidase of S. digitata systems showed an inhibition of 96.5 and 92.6% respectively, in the Culex systems they showed an inhibition of 93.3% and an activation of 18% respectively. The differences clearly indicate the existence of basic differences in GAG metabolism of vector and parasite. 相似文献
8.
G Y Lakshmi 《Indian journal of experimental biology》1989,27(10):903-906
Effects of lithium in vivo and in vitro on the two molecular forms of Na+,K(+)-ATPase in rat brain were investigated. Inhibition by strophanthidin, affinity to monovalent cations and cellular localization of the enzyme were used to differentiate the two molecular forms. K+ dependent p-nitrophenylphosphatase activity and strophanthidin inhibition studies revealed selective increase in the activity of low affinity form but not high affinity form of the enzyme following lithium treatment. Na+ sensitivity of neither forms of Na+,K(+)-ATPase was changed but K+ sensitivity of low affinity form was increased due to lithium. Lithium showed biphasic effects on low affinity form of the enzyme; activation at low concentration and inhibition at high concentration. The results suggest that lithium in vivo regulates the concentration of extra cellular potassium by selectively acting at K+ site of low affinity form of the enzyme (astroglial) but not on high affinity form (neuronal enzyme) and leading to changes in neuronal depolarization. 相似文献
9.
Summary The influence of trace elements (Co2+, Ni2+ and Fe3+) in varying concentrations and combination, was studied in 1.5 m3 Khadi & Village Industries Commission (KVIC) digesters for biogas generation from mangopeel. Addition of these trace metals enhanced the biogas yield and methane content moderately, the maximum being with the iron fed digester. The digesters were always found to be stable without much variation in total volatile fatty acids (VFA), pH, total alkalinity and other parameters. A methane content of 62% and biogas yield of 0.49 m3/kg VS added was obtained with 4000 mg/L FeCl3 supplemented mangopeel fed digester as compared to control having biogas yield of 0.22 m3/kg VS added with a methane content of about 48–50%. 相似文献
10.
Lionel Sibold Dominique Pariot Lakshmi Bhatnagar Marc Henriquet Jean-Paul Aubert 《Molecular & general genetics : MGG》1985,200(1):40-46
Summary Using the Southern hybridization technique, homologies were examined between restricted DNA of four methanogenic bacteria (Methanobacterium ivanovi, Methanobacterium thermoautotrophicum, Methanococcus voltae, Methanosarcina barkeri) and the nif (nitrogen fixation) genes of Klebsiella pneumoniae and Anabaena strain 7120. With K. pneumoniae probes, no hybridization was observed with nifA, nifNE, and nifJ but positive results were obtained with the nifHDK genes coding for nitrogenase. Homology was detected, in the four strains, with K. pneumoniae and Anabaena nifH probes. In M. voltae and M. ivanovi, the homology found with nifH was estimated to be about 70% and a weaker hybridization was observed also with nifD and nifK. In M. voltae, the sequence homologous to nifH was found on a 3.0 kbp HindIII fragment and sequences homologous to nifD and nifK on a 3.8 kbp HindIII fragment. The 3.0 kbp fragment was cloned and the region homologous to nifH was localized more precisely. When this fragment was used as a probe against other DNAs, it behaved as a K. pneumoniae and Anabaena nifH probe. The results suggest that the structural genes for nitrogenase may be present in archaebacteria and raise interesting questions regarding their evolution. 相似文献