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61.
Manda Sathish Sabanis Chetan Dushantrao Shalini Nekkanti Ramya Tokala Soujanya Thatikonda Yellaiah Tangella Gunda Srinivas Shirisha Cherukommu Namballa Hari Krishna Nagula Shankaraiah Narayana Nagesh Ahmed Kamal 《Bioorganic & medicinal chemistry》2018,26(17):4916-4929
A series of new C3-trans-cinnamide linked β-carboline conjugates has been synthesized by coupling between various β-carboline amines and substituted cinnamic acids. Evaluation of their anti-proliferative activity against a panel of selected human cancer cell lines such as A549 (lung cancer), MCF-7 (breast cancer), B16 (melanoma), HeLa (cervical cancer) and a normal cell line NIH3T3 (mouse embryonic fibroblast cell line), suggested that the newly designed conjugates are considerably active against all the tested cancer cell lines with IC50 values 13–45?nM. Moreover, the conjugates 8v and 8x were the most active against MCF-7 cells (14.05?nM and 13.84?nM respectively) and also even potent on other cell lines tested. Further, detailed investigations such as cell cycle analysis, apoptosis induction study, topoisomerase I inhibition assay, DNA binding affinity and docking studies revealed that these new conjugates are DNA interactive topoisomerase I inhibitors. 相似文献
62.
Denson K. McLain Karamjit S. Rai P. Nagesh Rao 《Evolution; international journal of organic evolution》1985,39(5):998-1008
Ethological isolation among eight species of mosquitoes in the Aedes scutellaris subgroup of the south Pacific was investigated by offering females a simultaneous choice between males of their own species and males of another species. The degree of ethological isolation between these largely allopatric, island-dwelling mosquitoes was associated with time since the species had become geographically isolated by the fragmentation of the Outer Melanesian Arc 2–10 mya. The degree of ethological isolation between species pairs was observed to be significantly correlated with the degree of genetic isolation based on other published studies of allozyme variation and percentage egg hatch from interspecific hybridizations. However, ethological isolation was asymmetrical for some species pairs within the same island region. Asymmetrical isolation was especially prominent in Polynesia, where females of two older species discriminated against males of newer species, while females of the newer species failed to discriminate. 相似文献
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Nagesh Pulicherla Leah A. Pogorzala Heather C. O′Farrell Faik N. Musayev J. Neel Scarsdale Elaine A. Sia Jason P. Rife 《Journal of molecular biology》2009,391(5):884-474
The enzymes of the KsgA/Dim1 family are universally distributed throughout all phylogeny; however, structural and functional differences are known to exist. The well-characterized function of these enzymes is to dimethylate two adjacent adenosines of the small ribosomal subunit in the normal course of ribosome maturation, and the structures of KsgA from Escherichia coli and Dim1 from Homo sapiens and Plasmodium falciparum have been determined. To this point, no examples of archaeal structures have been reported. Here, we report the structure of Dim1 from the thermophilic archaeon Methanocaldococcus jannaschii. While it shares obvious similarities with the bacterial and eukaryotic orthologs, notable structural differences exist among the three members, particularly in the C-terminal domain. Previous work showed that eukaryotic and archaeal Dim1 were able to robustly complement for KsgA in E. coli. Here, we repeated similar experiments to test for complementarity of archaeal Dim1 and bacterial KsgA in Saccharomyces cerevisiae. However, neither the bacterial nor the archaeal ortholog could complement for the eukaryotic Dim1. This might be related to the secondary, non-methyltransferase function that Dim1 is known to play in eukaryotic ribosomal maturation. To further delineate regions of the eukaryotic Dim1 critical to its function, we created and tested KsgA/Dim1 chimeras. Of the chimeras, only one constructed with the N-terminal domain from eukaryotic Dim1 and the C-terminal domain from archaeal Dim1 was able to complement, suggesting that eukaryotic-specific Dim1 function resides in the N-terminal domain also, where few structural differences are observed between members of the KsgA/Dim1 family. Future work is required to identify those determinants directly responsible for Dim1 function in ribosome biogenesis. Finally, we have conclusively established that none of the methyl groups are critically important to growth in yeast under standard conditions at a variety of temperatures. 相似文献
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Narayana B Ashalatha BV Vijaya Raj KK Fernandes J Sarojini BK 《Bioorganic & medicinal chemistry》2005,13(15):4638-4644
An efficient and modified synthesis of ethyl-4-nitro/5-nitro/6-nitro and 7-nitroindole-2-carboxylates is described. Carbohydrazides of corresponding ethyl nitroindole-2-carboxylates underwent smooth one-step transformation to 1,3,4-oxadiazolyl nitroindoles (4a-l) on reaction with aromatic carboxylic acids in the presence of phosphorus oxychloride. An alternate method to synthesize 1,3,4-oxadiazolyl nitroindoles is also described. Among the newly synthesized 1,3,4-oxadiazolyl nitroindoles, a few compounds are studied for anti-inflammatory activity. 相似文献
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Maria Pratheepa Sushil Kumar Jalali Robinson Silvester Arokiaraj Thiruvengadam Venkatesan Mandadi Nagesh Madhusmita Panda Sharath Pattar 《Bioinformation》2014,10(2):98-100
Insect Barcode Information System called as Insect Barcode Informática (IBIn) is an online database resource developed by the
National Bureau of Agriculturally Important Insects, Bangalore. This database provides acquisition, storage, analysis and
publication of DNA barcode records of agriculturally important insects, for researchers specifically in India and other countries. It
bridges a gap in bioinformatics by integrating molecular, morphological and distribution details of agriculturally important insects.
IBIn was developed using PHP/My SQL by using relational database management concept. This database is based on the client–
server architecture, where many clients can access data simultaneously. IBIn is freely available on-line and is user-friendly. IBIn
allows the registered users to input new information, search and view information related to DNA barcode of agriculturally
important insects.This paper provides a current status of insect barcode in India and brief introduction about the database IBIn.
Availability
http://www.nabg-nbaii.res.in/barcode 相似文献70.
Olanzapine is the one of first line antipsychotic drug for schizophrenia and other serious mental illness. However, it is associated with troublesome metabolic side-effects, particularly body weight gain and obesity. The antagonistic affinity to histamine H1 receptors (H1R) of antipsychotic drugs has been identified as one of the main contributors to weight gain/obesity side-effects. Our previous study showed that a short term (2 weeks) combination treatment of betahistine (an H1R agonist and H3R antagonist) and olanzapine (O+B) reduced (−45%) body weight gain induced by olanzapine in drug-naïve rats. A key issue is that clinical patients suffering with schizophrenia, bipolar disease and other mental disorders often face chronic, even life-time, antipsychotic treatment, in which they have often had previous antipsychotic exposure. Therefore, we investigated the effects of chronic O+B co-treatment in controlling body weight in female rats with chronic and repeated exposure of olanzapine. The results showed that co-administration of olanzapine (3 mg/kg, t.i.d.) and betahistine (9.6 mg/kg, t.i.d.) significantly reduced (−51.4%) weight gain induced by olanzapine. Co-treatment of O+B also led to a decrease in feeding efficiency, liver and fat mass. Consistently, the olanzapine-only treatment increased hypothalamic H1R protein levels, as well as hypothalamic pAMPKα, AMPKα and NPY protein levels, while reducing the hypothalamic POMC, and UCP1 and PGC-1α protein levels in brown adipose tissue (BAT). The olanzapine induced changes in hypothalamic H1R, pAMPKα, BAT UCP1 and PGC-1α could be reversed by co-treatment of O+B. These results supported further clinical trials to test the effectiveness of co-treatment of O+B for controlling weight gain/obesity side-effects in schizophrenia with chronic antipsychotic treatment. 相似文献