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151.
Rice long repetitive DNA (9–20 kbp) reassociating at Cot 50 M.s was cloned in pBR325. Out of several recombinants (Camr Ampr Tets), only a few were selected randomly for further characterization. The insert size in all these clones was 3–4 kbp. Restriction enzyme analysis showed the absence ofEcoRI andBclI sites, presence of a singlePstI andPvuII site and multiple sites forAluI in 3 clones namely pRLl, pRL7 and pRL10. TheBamHI-PstI fragment of about 0.4 kbp in the pRL7 insert DNA (pRL7-0.4 kbp) was subcloned in M13mpl8 and partially sequenced using Sanger’s dideoxynucleotide chain termination method. Dot matrix comparison of this sequence with rice rDNA sequences revealed low homology with the 25 S rDNA sequence of rice, however, hybridisation did not indicate any homology.  相似文献   
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In an effort to discover potent antibacterials based on the entropically favored 'bioactive conformation' approach, a series of novel tricyclic molecules mimicking the conformationally constrained structure of Linezolid is reported. Based on the initial tricyclic molecule 1, the benzazepine derivative 2 was designed where the tricyclic structure had more flexibility around C-N bond compared to 1. While, the molecule 2 was less active, the molecule 3 showed promising antibacterial activity presumably after having obtained rigidity due to pyrrole ring. The syntheses, SAR studies, and evaluation of 3 as a lead compound are reported.  相似文献   
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Insulin stimulates endothelial NO synthesis, at least in part mediated by phosphorylation and activation of endothelial NO synthase at Ser1177 and Ser615 by Akt. We have previously demonstrated that insulin-stimulated NO synthesis is inhibited under high culture glucose conditions, without altering Ca2+-stimulated NO synthesis or insulin-stimulated phosphorylation of eNOS. This indicates that stimulation of endothelial NO synthase phosphorylation may be required, yet not sufficient, for insulin-stimulated nitric oxide synthesis. In the current study we investigated the role of supply of the eNOS substrate, l-arginine as a candidate parallel mechanism underlying insulin-stimulated NO synthesis in cultured human aortic endothelial cells. Insulin rapidly stimulated l-arginine transport, an effect abrogated by incubation with inhibitors of phosphatidylinositol-3′-kinase or infection with adenoviruses expressing a dominant negative mutant Akt. Furthermore, supplementation of endothelial cells with extracellular l-arginine enhanced insulin-stimulated NO synthesis, an effect reversed by co-incubation with the l-arginine transport inhibitor, l-lysine. Basal l-arginine transport was significantly increased under high glucose culture conditions, yet insulin-stimulated l-arginine transport remained unaltered. The increase in l-arginine transport elicited by high glucose was independent of the expression of the cationic amino acid transporters, hCAT1 and hCAT2 and not associated with any changes in the activity of ERK1/2, Akt or protein kinase C (PKC). We propose that rapid stimulation of L-arginine transport contributes to insulin-stimulated NO synthesis in human endothelial cells, yet attenuation of this is unlikely to underlie the inhibition of insulin-stimulated NO synthesis under high glucose conditions.  相似文献   
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Many structural and functional properties possessed by plants have great potentials to stimulate new concepts and inno-vative ideas in the field of biomimetic engineering. The key inputs from biology can be used for creation of efficient and op-timized structures. The study of the geometry and folding pattern of leaves of Mimosa pudica,referred as Sensitive Plant,reveals some of the peculiar characteristics during folding and unfolding. When the leaf is touched,it quickly folds its leaflets and pinnae and droops downward at the petiole attachment. With the help of experiments on simulation model,the variations in angle of leaflets and degree of compaction after folding are investigated.  相似文献   
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Microalgae are photosynthetic eukaryotes which are primary producers in the food chain and also excellent sources for bioactive compounds such as alkaloids, flavonoids, phenols, saponins and other fine chemicals. In the present study, the microalga Scenedesmus bajacalifornicus BBKLP-07 was subjected to soxhlet extraction using solvents like chloroform, acetone, ethanol, methanol and aqueous solvents. All the solvents were tested for the presence of phytochemical constituents such as alkaloids, flavonoids, glycosides, phenols, lignin’s, saponins, sterols, tannins, anthraquinone and reducing sugar using the standard procedures. Furthermore, all the crude extracts were subjected to antidiabetic, antioxidant, anti-inflammatory and antimicrobial activities. Antidiabetic activity of the microalgal extracts was observed maximum in Aqueous extract. Methanolic extracts have shown maximum antioxidant activity and chloroform extracts have exhibited highest anti-inflammatory effects. Antimicrobial activities were tested against E.coli, S, typhi, C.perfringens and B.subtilis bacteria and fungi A.niger, and C. albicans. Therefore, the green microalga Scenedesmus bajacalifornicus BBKLP-07 is a rich source of biological active compounds and nutraceuticals and can be exploited for commercial applications.

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Probiotics and Antimicrobial Proteins - Hylak® forte is a postbiotic that inhibits the growth of pathogenic bacteria by reducing intestinal pH. It is assumed the potential presence of...  相似文献   
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Interleukin-17A (IL-17A) is one of the member of IL-17 family consisting of other five members (IL-17B to IL-17F). The Gamma delta (γδ) T cells and T helper 17 (Th17) cells are the major producers of IL-17A. Aberrant signaling by IL-17A has been implicated in the pathogenesis of several autoimmune diseases including idiopathic pulmonary fibrosis, acute lung injury, chronic airway diseases, and cancer. Activation of the IL-17A/IL-17 receptor A (IL-17RA) system regulates phosphoinositide 3-kinase/AKT serine/threonine kinase/mammalian target of rapamycin (PI3K/AKT/mTOR), mitogen-activated protein kinases (MAPKs) and activation of nuclear factor-κB (NF-κB) mediated signaling pathways. The IL-17RA activation orchestrates multiple downstream signaling cascades resulting in the release of pro-inflammatory cytokines such as interleukins (IL)-1β, IL-6, and IL-8, chemokines (C-X-C motif) and promotes neutrophil-mediated immune response. Considering the biomedical importance of IL-17A, we developed a pathway resource of signaling events mediated by IL-17A/IL-17RA in this study. The curation of literature data pertaining to the IL-17A system was performed manually by the NetPath criteria. Using data mined from the published literature, we describe an integrated pathway reaction map of IL-17A/IL-17RA consisting of 114 proteins and 68 reactions. That includes detailed information on IL-17A/IL-17RA mediated signaling events of 9 activation/inhibition events, 17 catalysis events, 3 molecular association events, 68 gene regulation events, 109 protein expression events, and 6 protein translocation events. The IL-17A signaling pathway map data is made freely accessible through the WikiPathways Database (https://www.wikipathways.org/index.php/Pathway: WP5242).Supplementary InformationThe online version contains supplementary material available at 10.1007/s12079-022-00686-y.  相似文献   
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