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791.
Bioprocess and Biosystems Engineering - Bacillus pumilus, the thermophilic microorganism, was used to biosynthesise lipase of specific activity 5173 U. The purified lipase was highly stable in the...  相似文献   
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The synthesis of several analogues of ma’edamines A and B are reported. The synthesized compounds were tested on hormone receptor positive and HER2 positive breast cancer cell lines, by MTT assay. MED-114, 115, 117, 119, 120, 124, 128 and 131 were found to be equally active as Lapatinib on HER2 +ve cell line SKBR3.  相似文献   
795.
Biomineralization-inspired preparation of nanoparticles by marine microorganisms is in the limelight of modern nanotechnology. In recent years, the use of marine microorganisms for the synthesis of nanoparticles has been gaining importance due to the simplicity and eco-friendliness of the approach. Here we describe the synthesis of silver nanoparticles using halotolerant Bacillus sp. isolated from the southern coastal waters of India. Our selective and enriched isolation technique resulted in the isolation of a silver nitrate-resistant novel marine Bacillus sp. isolated from sediments collected at Ennore Port, Chennai, India. The strain was characterized by the polyphasic taxonomic approach, and phenotypic and phylogenetic analysis identified the strain as Bacillus sp. VITSSN01. The resistant strain was further assayed for the synthesis of silver nanoparticles and its biological activity evaluated. Nanoparticles were synthesized under optimized nutritional and cultural conditions with shaking and the production continuously monitored. The nanoparticles thus produced were then characterized by atomic force microscopy, X-ray diffraction, Fourier transform-infrared spectrophotometer and transmission electron microscopy. The mean particle size was 46 nm. Hemotological toxicity of nanoparticles is very severe form and less studied. We therefore checked the synthesized silver nanoparticles for toxicity against erythrocytes and found that the silver nanoparticles exhibited moderate hemolytic activity against human erythrocytes, with a half maximal effective concentration (EC50) value of 60 μg/ml. Microscopic studies of the treated erythrocytes showed slight structural perturbations. The results of our study strongly suggest that marine microorganisms could be a potential source for the rapid and eco-friendly synthesis of nanoparticles.  相似文献   
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Once considered to be predominantly a positive regulator of immune function, B cells are increasingly getting attributed with new and diversified functions. In recent years a number of reports indicate that a definite regulatory function of B cell exists. A number of B cell subsets that shares various developmental markers shown to have the ability to produce the suppressive cytokine IL-10. A particularly strong candidate with distinct IL-10 production profile is CD19hiCD1dhiCD5+ population, which constitutes about 1–2 % of splenic B cells. These B cells are also called B10 cells as they produce large amount of IL-10. Increasingly it is becoming clear that a variety of regulatory B cell population exists and expands during inflammatory condition and autoimmune disease. A detailed study of development and mechanism that governs B reg generation may provide us with valuable information for therapeutic intervention.  相似文献   
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Skin mucosal lymphoid tissues of fish are the first line of defence against pathogen invasion. We investigated the effects of Lactiplantibacillus plantarum subsp. plantarum L7, singularly or in combination with Limosilactobacillus reuteri P16, on mucosal immunity and diseases resistance of carp Cyprinus carpio. C. carpio (average weight: 26.28 ± 1.02 g) were divided into five experimental groups. Fish in each group were fed with one of the following potential probiotic-supplemented diets: control (0 – basal diet), D1 (107 CFU/g L7), D2 (108 CFU/g L7), D3 (109 CFU/g L7), and D4 (108 CFU/g L7 + 108 CFU/g P16). Eight weeks post-feeding, growth performance was higher in D4, with a final weight gain of 67.18 ± 1.47 g. Results showed a significantly higher skin mucosal lysozyme, alkaline phosphatase, mucus protein level, superoxide dismutase, and catalase activities in D2 and D4 compared to the control. However, potential probiotics had no significant effect on skin mucosal immunoglobulin level. Skin mucus of D4 exhibited stronger inhibition zones against pathogenic bacterial strains. Moreover, digestive enzyme activities (protease, lipase) were highest in D4. Intesinal lactic acid bacterial counts of fish fed combind probiotics (i.e. D4) was significantly higher than the control. Further, supplementation of potential probiotics altered the expression of IL-1β, TNF-α, and IL-10 cytokines. Fish from D4 exhibited significantly higher relative post-challenge survival (69.7%) against Aeromonas hydrophila, followed by D2 (66.67%). Therefore, the inclusion of L. plantarum subsp. plantarum L7 at 108 CFU/g or in combination with L. reuteri P16 could enhance the growth performance, mucosal immune responses, and disease resistance of C. carpio.

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799.
Calcium/calmodulin-dependent protein kinase kinase 2 (CAMKK2) is a serine/threonine-protein kinase belonging to the Ca2+/calmodulin-dependent protein kinase subfamily. CAMKK2 has an autocatalytic site, which gets exposed when Ca2+/calmodulin (CAM) binds to it. This results in autophosphorylation and complete activation of CAMKK2. The three major known downstream targets of CAMKK2 are 5′-adenosine monophosphate (AMP)-activated protein kinase (AMPKα), calcium/calmodulin-dependent protein kinase 1 (CAMK1) and calcium/calmodulin-dependent protein kinase 4 (CAMK4). Activation of these targets by CAMKK2 is important for the maintenance of different cellular and physiological processes within the cell. CAMKK2 is found to be important in neuronal development, bone remodeling, adipogenesis, and systemic glucose homeostasis, osteoclastgensis and postnatal myogensis. CAMKK2 is reported to be involved in pathologies like Duchenne muscular dystrophy, inflammation, osteoporosis and bone remodeling and is also reported to be overexpressed in prostate cancer, hepatic cancer, ovarian and gastric cancer. CAMKK2 is involved in increased cell proliferation and migration through CAMKK2/AMPK pathway in prostate cancer and activation of AKT in ovarian cancer. Although CAMKK2 is a molecule of great importance, a public resource of the CAMKK2 signaling pathway is currently lacking. Therefore, we carried out detailed data mining and documentation of the signaling events associated with CAMKK2 from published literature and developed an integrated reaction map of CAMKK2 signaling. This resulted in the cataloging of 285 reactions belonging to the CAMKK2 signaling pathway, which includes 33 protein–protein interactions, 74 post-translational modifications, 7 protein translocation events, and 22 activation/inhibition events. Besides, 124 gene regulation events and 25 activator/inhibitors involved in CAMKK2 activation were also cataloged. The CAMKK2 signaling pathway map data is made freely accessible through WikiPathway database (https://www.wikipathways.org/index.php/Pathway:WP4874). We expect that data on a signaling map of CAMKK2 will provide the scientific community with an improved platform to facilitate further molecular as well as biomedical investigations on CAMKK2 and its utility in the development of biomarkers and therapeutic targets.Electronic supplementary materialThe online version of this article (10.1007/s12079-020-00592-1) contains supplementary material, which is available to authorized users.  相似文献   
800.
The effect of α-tocopherol on doxorubicin induced changes in intestinal brush border and basolateral membranes were studied in rats. Rats were treated with doxorubicin (2.5 mg/kg body wt.), intravenously, weekly for 8 weeks. α-Tocopherol (400 mg/kg body wt.) was given orally, daily for 2 months. Intestinal basolateral membrane bound ATPases and brush border membrane bound alkaline phosphatase activities were found to be decreased significantly in doxorubicin treated rats. The lipid peroxide level was found to be elevated with a significant depletion in membrane sulphydryl groups. In α-tocopherol coadministered animals, the enzyme activities were found to be restored with concomitant reduction in lipid peroxide levels and an increase in the membrane sulphydryl groups. The membrane cholesterol and phospholipid levels which were altered in doxorubicin treated animals were found to be maintained significantly. The results are discussed with reference to the effect of α-tocopherol on lipid peroxidation and membrane sulphydryl groups.  相似文献   
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