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101.
Supriya Khedkar Sushma Prabhakara Ramya Malarini Loganathan Chandana S Malali Gowda Gayathri Arakere Aswin Sai Narain Seshasayee 《Journal of bacteriology》2012,194(24):6946-6947
We report the draft genome sequence of methicillin-resistant Staphylococcus aureus (MRSA) strain ST672, an emerging disease clone in India, from a septicemia patient. The genome size is about 2.82 Mb with 2,485 open reading frames (ORFs). The staphylococcal cassette chromosome mec (SCCmec) element (type V) and immune evasion cluster appear to be different from those of strain ST772 on preliminary examination. 相似文献
102.
A. Sai Ramesh Imran Khan Md. Farhan Padma Thiagarajan 《Cell biochemistry and biophysics》2013,67(3):1391-1396
CYP1A1 gene belongs to the cytochrome P450 family and is known better as smokers’ gene due to its hyperactivation as a consequence of long term smoking. The expression of CYP1A1 induces polycyclic aromatic hydrocarbon production in the lungs, which when over expressed, is known to cause smoking related diseases, such as cardiovascular pathologies, cancer, and diabetes. Single nucleotide polymorphisms (SNPs) are the simplest form of genetic variations that occur at a higher frequency, and are denoted as synonymous and non-synonymous SNPs on the basis of their effects on the amino acids. This study adopts a systematic in silico approach to predict the deleterious SNPs that are associated with disease conditions. It is inferred that four SNPs are highly deleterious, among which the SNP with rs17861094 is commonly predicted to be harmful by all tools. Hydrophobic (isoleucine) to hydrophilic (serine) amino acid variation was observed in the candidate gene. Hence, this investigation aims to characterize a candidate gene from 159 SNPs of CYP1A1. 相似文献
103.
Clostridium thermocellum SS8 produced both carboxymethylcellulase (CMCase) and Avicelase when grown on cellulose. CMCase activity was unaffected by Ca2+, Mg2+, dithionate or dithiothreitol (DTT). Avicelase activity increased 2-fold with 5 mM DTT and 10 mM Ca2+. Cellulase and amylase were produced when a celluloseadapted culture was grown on starch. The mould grew best on sucrose and was inhibited by NaCl above 10 g/l. 相似文献
104.
Levamisole suppresses adipogenesis of aplastic anaemia‐derived bone marrow mesenchymal stem cells through ZFP36L1‐PPARGC1B axis
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105.
Sai Sunil Kumar Mallineni Yongchang Dong Herbert Behlow Apparao M. Rao Ramakrishna Podila 《Liver Transplantation》2018,8(10)
A new “wireless” paradigm for harvesting mechanical energy via a 3D‐printed wireless triboelectric nanogenerator (W‐TENG) comprised of an ecofriendly graphene polylactic acid (gPLA) nanocomposite and Teflon is demonstrated. The W‐TENG generates very high output voltages >2 kV with a strong electric field that enables the wireless transmission of harvested energy over a distance of 3 m. The W‐TENG exhibited an instantaneous peak power up to 70 mW that could be wirelessly transmitted for storage into a capacitor obviating the need for hard‐wiring or additional circuitry. Furthermore, the use of W‐TENG for wireless and secure actuation of smart‐home applications such as smart tint windows, temperature sensors, liquid crystal displays, and security alarms either with a single or a specific user‐defined passcode of mechanical pulses (e.g., Fibonacci sequence) is demonstrated. The scalable additive manufacturing approach for gPLA‐based W‐TENGs, along with their high electrical output and unprecedented wireless applications, is poised for revolutionizing the present mechanical energy harvesting technologies. 相似文献
106.
Daniel C. Hannah Gopalakrishnan Sai Gautam Pieremanuele Canepa Gerbrand Ceder 《Liver Transplantation》2018,8(20)
A thermodynamic analysis of the driving forces is presented for intercalation and conversion reactions in battery cathodes across a range of possible working ion, transition metal, and anion chemistries. Using this body of results, the importance of polymorph selection as well as chemical composition on the ability of a host cathode to support intercalation reactions is analyzed. It is found that the accessibility of high energy charged polymorphs in oxides generally leads to larger intercalation voltages favoring intercalation reactions, whereas sulfides and selenides tend to favor conversion reactions. Furthermore, it is observed that Cr‐containing cathodes favor intercalation more strongly than those with other transition metals. Finally, it is concluded that two‐electron reduction of transition metals (as is possible with the intercalation of a 2 + ion) will favor conversion reactions in the compositions studied. 相似文献
107.
Bin Zhang Ronne Wee Yeh Yeo Ruenn Chai Lai Eugene Wei Kian Sim Keh Chuang Chin Sai Kiang Lim 《Cytotherapy》2018,20(5):687-696
Background aims
The immunomodulatory property of mesenchymal stromal cell (MSC) exosomes is well documented. On the basis of our previous report that MSC exosomes increased regulatory T-cell (Treg) production in mice with allogenic skin graft but not in ungrafted mice, we hypothesize that an activated immune system is key to exosome-mediated Treg production.Methods
To test our hypothesis, MSC exosomes were incubated with mouse spleen CD4+ T cells that were activated with either anti-CD3/CD28 mAbs or allogenic antigen-presenting cell (APC)-enriched spleen CD11c+ cells to determine whether production of mouse CD4+CD25+ T cells or CD4+CD25+Foxp3+ Tregs could be induced. MSC exosomes were also administered to the lethal chimeric human-SCID mouse model of graft-versus-host disease (GVHD) in which human peripheral blood mononuclear cells were infused into irradiated NSG mice to induce GVHD.Results
We report here that MSC exosome–induced production of CD4+CD25+ T cells or CD4+CD25+Foxp3+ Tregs from CD4+ T cells activated by allogeneic APC-enriched CD11C+ cells but not those activated by anti-CD3/CD28 mAbs. This induction was exosome- and APC dose–dependent. In the mouse GVHD model in which GVHD was induced by transplanted human APC-stimulated human anti-mouse CD4+ T cell effectors, MSC exosome alleviated GVHD symptoms and increased survival. Surviving exosome-treated mice had a significantly higher level of human CD4+CD25+CD127low/– Tregs than surviving mice treated with Etanercept, a tumor necrosis factor inhibitor.Conclusions
MSC exosome enhanced Treg production in vitro and in vivo through an APC-mediated pathway. 相似文献108.
采用二代测序(next-generation sequencing,NGS)技术,对上海生物制品研究所有限责任公司(简称SIBP)2015-2017这3个年度生产的Oka株水痘疫苗进行深度测序,从分子水平分析疫苗质量的一致性,并与不同厂家疫苗/毒种进行比较,分析它们之间的遗传特征相关性。结果显示,3个年度生产的水痘疫苗中平均有77个位点的疫苗型位点检出频率(proportion of vaccine-type allele,Pv)≥10%,至少在两批疫苗中出现Pv≥10%的位点数共76个,两两之间Pv最大差值<10%,与平均值的最大差值为<5%。共有40个位点的Pv均值≥30%,其中19个位点导致氨基酸残基变异;15个位于ORF62区域。筛选出35个位点,比较5个公司水痘疫苗/毒种的Oka株病毒基因序列,结果显示它们之间存在相关性,同时存在一定的差异。研究表明,SIBP不同年度生产的水痘疫苗Oka株病毒具有良好的分子水平上的一致性,为疫苗质量管理与市场监督提供了方法和基础数据。 相似文献
109.
Convolutional neural network‐based malaria diagnosis from focus stack of blood smear images acquired using custom‐built slide scanner
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The present paper introduces a focus stacking‐based approach for automated quantitative detection of Plasmodium falciparum malaria from blood smear. For the detection, a custom designed convolutional neural network (CNN) operating on focus stack of images is used. The cell counting problem is addressed as the segmentation problem and we propose a 2‐level segmentation strategy. Use of CNN operating on focus stack for the detection of malaria is first of its kind, and it not only improved the detection accuracy (both in terms of sensitivity [97.06%] and specificity [98.50%]) but also favored the processing on cell patches and avoided the need for hand‐engineered features. The slide images are acquired with a custom‐built portable slide scanner made from low‐cost, off‐the‐shelf components and is suitable for point‐of‐care diagnostics. The proposed approach of employing sophisticated algorithmic processing together with inexpensive instrumentation can potentially benefit clinicians to enable malaria diagnosis. 相似文献
110.
Zaira Aversa Thomas A. White Amanda A. Heeren Cassondra A. Hulshizer Dominik Saul Xu Zhang Anthony J. A. Molina Leanne M. Redman Corby K. Martin Susan B. Racette Kim M. Huffman Manjushri Bhapkar Sundeep Khosla Sai Krupa Das Roger A. Fielding Elizabeth J. Atkinson Nathan K. LeBrasseur 《Aging cell》2024,23(2):e14038
Calorie restriction (CR) with adequate nutrient intake is a potential geroprotective intervention. To advance this concept in humans, we tested the hypothesis that moderate CR in healthy young-to-middle-aged individuals would reduce circulating biomarkers of cellular senescence, a fundamental mechanism of aging and aging-related conditions. Using plasma specimens from the Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy (CALERIE™) phase 2 study, we found that CR significantly reduced the concentrations of several senescence biomarkers at 12 and 24 months compared to an ad libitum diet. Using machine learning, changes in biomarker concentrations emerged as important predictors of the change in HOMA-IR and insulin sensitivity index at 12 and 24 months, and the change in resting metabolic rate residual at 12 months. Finally, using adipose tissue RNA-sequencing data from a subset of participants, we observed a significant reduction in a senescence-focused gene set in response to CR at both 12 and 24 months compared to baseline. Our results advance the understanding of the effects of CR in humans and further support a link between cellular senescence and metabolic health. 相似文献