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331.
Sharma MK Jani D Thungapathra M Gautam JK Meena LS Singh Y Ghosh A Tyagi AK Sharma AK 《Journal of biotechnology》2008,135(1):22-27
332.
Abdul-Ghani MA Matsuda M Jani R Jenkinson CP Coletta DK Kaku K DeFronzo RA 《American journal of physiology. Endocrinology and metabolism》2008,295(2):E401-E406
To assess the relationship between the fasting plasma glucose (FPG) concentration and insulin secretion in normal glucose tolerance (NGT) and impaired glucose tolerance (IGT) subjects, 531 nondiabetic subjects with NGT (n = 293) and IGT (n = 238; 310 Japanese and 232 Mexican Americans) received an oral glucose tolerance test (OGTT) with measurement of plasma glucose, insulin, and C-peptide every 30 min. The insulin secretion rate was determined by plasma C-peptide deconvolution. Insulin sensitivity (Matsuda index) was measured from plasma insulin and glucose concentrations. The insulin secretion/insulin resistance (IS/IR) or disposition index was calculated as DeltaISR/DeltaG / IR. As FPG increased in NGT subjects, the IS/IR index declined exponentially over the range of FPG from 70 to 125 mg/dl. The relationship between the IS/IR index and FPG was best fit with the equation: 28.8 exp(-0.036 FPG). For every 28 mg/dl increase in FPG, the IS/IR index declined by 63%. A similar relationship between IS/IR index and FPG was observed in IGT. However, the decay constant was lower than in NGT. The IS/IR index for early-phase insulin secretion (0-30 min) was correlated with the increase in FPG in both NGT and IGT (r = -0.43, P < 0.0001 and r = -0.20, P = 0.001, respectively). However, the correlation between late-phase insulin secretion (60-120 min) and FPG was not significant. In conclusion, small increments in FPG, within the "normal" range, are associated with a marked decline in glucose-stimulated insulin secretion and the decrease in insulin secretion with increasing FPG is greater in subjects with NGT than IGT and primarily is due to a decline in early-phase insulin secretion. 相似文献
333.
We investigated the bacterial community structure of Soldhar hot spring with extreme high temperature 95°C located in Uttarakhand, India using high throughput sequencing. Bacterial phyla Proteobacteria (88.8%), Deinococcus-Thermus (7.5%), Actinobacteria (2.3%), and Firmicutes (1.07%) were predominated in the sequencing survey, whereas Bacteroidetes, Verrucomicrobia, Aquificae and Acidobacteria were detected in relatively lower abundance in Soldhar hot spring. At the family level, Comamonadaceae (52.5%), Alteromonadaceae (15.9%), and Thermaceae (7.5%) were mostly dominated in the ecosystem followed by Chromatiaceae, Microbacteriaceae, and Cyclobacteriaceae. Besides, members of Rhodobacteraceae, Moraxellaceae, Xanthomonadaceae, Aquificaceae, Enterobacteriaceae, Bacillaceae, Methylophilaceae, etc. were detected as a relatively lower abundance. In the present study we discuss the overall microbial community structure and their relevance to the ecology of the Soldhar hot spring environment. 相似文献
334.
335.
A higher‐level classification of the Pannonian and western Pontic steppe grasslands (Central and Eastern Europe) 下载免费PDF全文
Wolfgang Willner Anna Kuzemko Jürgen Dengler Milan Chytrý Norbert Bauer Thomas Becker Claudia Biţă‐Nicolae Zoltán Botta‐Dukát Andraž Čarni János Csiky Ruzica Igić Zygmunt Kącki Iryna Korotchenko Matthias Kropf Mirjana Krstivojević‐Ćuk Daniel Krstonošić Tamás Rédei Eszter Ruprecht Luise Schratt‐Ehrendorfer Yuri Semenishchenkov Zvjezdana Stančić Yulia Vashenyak Denys Vynokurov Monika Janišová 《应用植被学》2017,20(1):143-158
336.
Yvonne A Kwaffo Mabel Sarpong-Duah Kwabena Owusu-Boateng Winfred SK Gbewonyo Jonathan P Adjimani Lydia Mosi 《Experimental biology and medicine (Maywood, N.J.)》2021,246(17):1884
Mycobacterium ulcerans produces a macrolide exotoxin, mycolactone which suppresses immune cells activity, is toxic to most cells and the key virulence factor in the pathogenesis of Buruli ulcer disease. Mycolactone is reported to mediate the production of reactive oxygen species in keratinocytes; cells that play critical role in wound healing. Increased levels of reactive oxygen species have been shown to disrupt the well-ordered process of wound repair; hence, the function of wound-healing cells such as macrophages, keratinocytes, and fibroblast could be impaired in the presence of the reactive oxygen species mediator, mycolactone. To ensure regeneration of tissues in chronic ulcers, with proper and timely healing of the wounds, natural antioxidants that can combat the effects of induced reactive oxygen species in wound-healing cells ought to be investigated. Reactive oxygen species activity was determined in mycolactone-treated RAW 264.7 macrophages and the scavenging ability of the antioxidants (ascorbic acid, gallic acid, and green tea kombucha) against mycolactone-induced reactive oxygen species (superoxide anions) was assessed using fluorescein probe (DCF-DA) and nitroblue tetrazolium dye. Cytotoxicity of the antioxidants, mycolactone, and the protective effect of the antioxidants on the cells upon treatment with mycolactone were determined using the Alamar blue assay. The expression levels of endogenous antioxidant enzyme genes (superoxide dismutase, catalase, and glutathione peroxidase) in response to mycolactone-mediated reactive oxygen species were determined using RT-qPCR. Mycolactone induced the production of reactive oxygen species in RAW 264.7 macrophages, and the resulting superoxide anions were scavenged by some of the antioxidants. The selected endogenous antioxidant enzyme genes in the macrophages were upregulated in the presence of the antioxidants and mycolactone. The exogenously supplied ascorbic acid and green tea kombucha offered moderate protection to the macrophages against the toxicity of mycolactone. We conclude that the results provide insights into alternate and adjunct therapeutic approaches in Buruli ulcer treatment, which could significantly attenuate the toxicity of the pathogenic factor; mycolactone. 相似文献
337.
Gary?L?Argraves Saurin?Jani Jeremy?L?Barth W?Scott?ArgravesEmail author 《BMC bioinformatics》2005,6(1):287
Background
Numerous microarray analysis programs have been created through the efforts of Open Source software development projects. Providing browser-based interfaces that allow these programs to be executed over the Internet enhances the applicability and utility of these analytic software tools. 相似文献338.
BACKGROUND: Measuring CD4 T-cell counts at low cost is relevant in dealing with the human immunodeficiency virus (HIV) epidemic throughout the developing world. The recently introduced novel concepts in gating strategies and sample stabilization facilitate affordable immunophenotyping by flow cytometry. However, the impact of these developments is still limited by the high cost of currently available flow cytometers. METHODS: Diode lasers emitting 10-15 mW at 635 nm are one-tenth the size and cost and require one thousandth the power of an equivalent 488-nm argon ion laser. We used the available 635-nm diode-based flow cytometers, including PA-II, Luminex 100, SuperMot, and FACSCalibur, to investigate whether these instruments can generate reliable CD4 counts when used with allophycocyanin (APC) and cyanin-5 (Cy5)-labeled CD4 antibodies. RESULTS: We document the feasibility of obtaining leucocyte differential counts using orthogonal side scatter (SSC) without the need for forward scatter (FSC). Accurate CD4% values among lymphocytes and leucocytes can be obtained by primary CD4 gating using a single CD4 monoclonal antibody conjugated to APC or Cy5. Double immunofluorescence (IF) staining with CD4-APC (FL1) and CD45-APC-Cy7 (FL2) introduces pan-leucogating for a convenient assessment of absolute CD4 counts on double platforms. We demonstrate that small flow cytometers with laser diodes are capable of delivering absolute CD4 T-cell counts with a precision similar to the performance of the current state-of-the-art single-platform instruments (e.g., the CytoronAbsolute; R(2) = 0.961). In this respect, they appear to be superior to the nonflow CD4 counting techniques. CONCLUSIONS: Accurate CD4 counts can be generated at minimal cost on red diode laser-operated flow cytometers, retaining the potential for high throughput capacity without compromising precision. With further improvements in volumetric technology and clinical software, these cytometers may develop into a new generation of inexpensive battery-operated laboratory hardware that combines cellular phenotyping with bead-based multiplexing immunoassays for (HIV) serology. 相似文献
339.
A.?GraffEmail author D.?Tropel SK.?Raman G.?Machaidze U.?Aebi P.?BurkhardEmail author 《NanoBioTechnology》2005,1(3):293-294
A challenging topic in cancer research is to create drug delivery system that can bring in a specific and noncytotoxic manner
a therapeutic compound. Usually, tumor targeting requires very specific compounds. Currently, peptide analogues like somatostatin,
neurotensin, or bombesin are used to target G-coupled receptors, which are overexpressed on tumor cells. However, many of
those analogues are rapidly degraded in the plasma and are cytotoxic [1–2]. Due to the limited efficiency and high toxicity
of conventional chemotherapy different strategies have been developed for non-cytotoxic cancer treatment and cancer localization
[3–5].
The recent development in bio-nanotechnology offers new avenues for cancer therapy. A lot of studies have been devoted to
nanoparticulate delivery systems (10–100nm) like lipid or polymer particles [6–8]. Due to the nanometer sized of such cargos,
the transportation of therapeutic compounds in the blood stream is increased in terms of time circulation. But their surface
functionalization to improve drug-targeting properties is usually complicated and rather uneffective.
We have recently designed a novel type of functional nanoparticles with regular icosahedral symmetry, mimicking small, rigid
viral capsids (Fig. 1 (A)) and a diameter of about 17 nm (Fig. 1 (C)) which self-assemble from single polypeptide chains (Fig.
1 (B)). 相似文献
340.
AM Moilanen J Rysä R Serpi E Mustonen Z Szabò J Aro J Näpänkangas O Tenhunen M Sutinen T Salo H Ruskoaho 《PloS one》2012,7(7):e41404