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961.
Sanjay Kar Samiran Sona Gauri Arpan Das Arijit Jana Chiranjit Maity Asish Mandal Pradeep K. Das Mohapatra Bikash R. Pati Keshab C. Mondal 《Bioprocess and biosystems engineering》2013,36(1):57-68
This study aimed to assess the variability in respect of titer and properties of xylanase from Trichoderma reesei SAF3 under both solid-state and submerged fermentation. SSF was initially optimized with different agro-residues and among them wheat bran was found to be the best substrate that favored maximum xylanase production of 219 U (gws)?1 at 96 h of incubation. The mycelial stage of the fungi and intracellular accumulation of Ca++ and Mg++ induced maximum enzyme synthesis. Inoculum level of 10 × 106 spores 5 g?1 of dry solid substrate and water activity of 0.6 were found to be optimum for xylanase production under SSF. Further optimization was made using a Box-Behnken design under response surface methodology. The optimal cultivation conditions predicted from canonical analysis of this model were incubation time (A) = 96–99 h, inoculum concentration (B) = 10 × 106 spores 5 g?1 of dry substrate, solid substrate concentration (C) = 10–12 g flask?1, initial moisture level (D) = 10 mL flask?1 (equivalent to a w = 0.55) and the level of xylanase was 299.7 U (gws)?1. Subsequent verification of these levels agreed (97 % similar) with model predictions. Maximum amount of xylanase was recovered with water (6:1, v/w) and under shaking condition (125 rpm). Purified xylanase from SSF showed better stability in salt and pH, was catalytically and thermodynamically more efficient over enzyme from SmF, though molecular weight of both enzymes was identical (53.8 kDa). 相似文献
962.
963.
964.
Background
We, and others, have shown that experimenting with cigarettes is a function of both non-genetic and genetic factors. In this analysis we ask: how much of the total risk of experimenting with cigarettes, among those who had not experimented with cigarettes when they enrolled in a prospective cohort, is attributable to genetic factors and to non-genetic factors?Methods
Participants (N = 1,118 Mexican origin youth), recruited from a large population-based cohort study in Houston, Texas, provided prospective data on cigarette experimentation over three years. Non-genetic data were elicited twice – baseline and follow-up. Participants were genotyped for 672 functional and tagging variants in the dopamine, serotonin and opioid pathways.Results
In the overall model, the adjusted combined non-genetic PAF was 71.2% and the adjusted combined genetic PAF was 58.5%. Among committed never smokers the adjusted combined non-genetic PAF was 67.0% and the adjusted combined genetic PAF was 53.5%. However, among cognitively susceptible youth, the adjusted combined non-genetic PAF was 52.0% and the adjusted combined genetic PAF was 68.4%.Conclusions
Our results suggest there may be differences in genotypes between youth who think they will try cigarettes in the future compared to their peers who think they will not and underscore the possibility that the relative influence of genetic vs. non-genetic factors on the uptake of smoking may vary between these two groups of youth.Impact
A clearer understanding of the relative role of genetic vs. non-genetic factors in the uptake of smoking may have implications for the design of prevention programs. 相似文献965.
Jesse F. Gregory III Youngja Park Yvonne Lamers Nirmalya Bandyopadhyay Yueh-Yun Chi Kichen Lee Steven Kim Vanessa da Silva Nikolas Hove Sanjay Ranka Tamer Kahveci Keith E. Muller Robert D. Stevens Christopher B. Newgard Peter W. Stacpoole Dean P. Jones 《PloS one》2013,8(6)
Marginal deficiency of vitamin B-6 is common among segments of the population worldwide. Because pyridoxal 5′-phosphate (PLP) serves as a coenzyme in the metabolism of amino acids, carbohydrates, organic acids, and neurotransmitters, as well as in aspects of one-carbon metabolism, vitamin B-6 deficiency could have many effects. Healthy men and women (age: 20-40 y; n = 23) were fed a 2-day controlled, nutritionally adequate diet followed by a 28-day low-vitamin B-6 diet (<0.5 mg/d) to induce marginal deficiency, as reflected by a decline of plasma PLP from 52.6±14.1 (mean ± SD) to 21.5±4.6 nmol/L (P<0.0001) and increased cystathionine from 131±65 to 199±56 nmol/L (P<0.001). Fasting plasma samples obtained before and after vitamin B6 restriction were analyzed by 1H-NMR with and without filtration and by targeted quantitative analysis by mass spectrometry (MS). Multilevel partial least squares-discriminant analysis and S-plots of NMR spectra showed that NMR is effective in classifying samples according to vitamin B-6 status and identified discriminating features. NMR spectral features of selected metabolites indicated that vitamin B-6 restriction significantly increased the ratios of glutamine/glutamate and 2-oxoglutarate/glutamate (P<0.001) and tended to increase concentrations of acetate, pyruvate, and trimethylamine-N-oxide (adjusted P<0.05). Tandem MS showed significantly greater plasma proline after vitamin B-6 restriction (adjusted P<0.05), but there were no effects on the profile of 14 other amino acids and 45 acylcarnitines. These findings demonstrate that marginal vitamin B-6 deficiency has widespread metabolic perturbations and illustrate the utility of metabolomics in evaluating complex effects of altered vitamin B-6 intake. 相似文献
966.
Rajshekhar Chatterjee Mary Hoffman Paul Cliften Surya Seshan Helen Liapis Sanjay Jain 《PloS one》2013,8(10)
We applied customized targeted next-generation exome sequencing (NGS) to determine if mutations in genes associated with renal malformations, Alport syndrome (AS) or nephrotic syndrome are a potential cause of renal abnormalities in patients with equivocal or atypical presentation. We first sequenced 4,041 exons representing 292 kidney disease genes in a Caucasian woman with a history of congenital vesicoureteral reflux (VUR), recurrent urinary tract infections and hydronephrosis who presented with nephrotic range proteinuria at the age of 45. Her biopsy was remarkable for focal segmental glomerulosclerosis (FSGS), a potential complication of longstanding VUR. She had no family history of renal disease. Her proteinuria improved initially, however, several years later she presented with worsening proteinuria and microhematuria. NGS analysis revealed two deleterious COL4A3 mutations, one novel and the other previously reported in AS, and a novel deleterious SALL2 mutation, a gene linked to renal malformations. Pedigree analysis confirmed that COL4A3 mutations were nonallelic and compound heterozygous. The genomic results in conjunction with subsequent abnormal electron microscopy, Collagen IV minor chain immunohistochemistry and progressive sensorineural hearing loss confirmed AS. We then modified our NGS approach to enable more efficient discovery of variants associated with AS or a subset of FSGS by multiplexing targeted exome sequencing of 19 genes associated with AS or FSGS in 14 patients. Using this approach, we found novel or known COL4A3 or COL4A5 mutations in a subset of patients with clinically diagnosed or suspected AS, APOL1 variants associated with FSGS in African Americans and novel mutations in genes associated with nephrotic syndrome. These studies demonstrate the successful application of targeted capture-based exome sequencing to simultaneously evaluate genetic variations in many genes in patients with complex renal phenotypes and provide insights into etiology of conditions with equivocal clinical and pathologic presentations. 相似文献
967.
Rini Joshi Ajit Kumar Sushma Manral Rajesh Sinha Shvetambri Arora Anju Sharma Sanjay Goel Namita Kalra Suvro Chatterji Bilikere S. Dwarakanath Diwan S. Rawat Anthony L. DePass Vishwajeet Rohil Daman Saluja Virinder S. Parmar Ashok K. Prasad Hanumantharao G. Raj 《Chemico-biological interactions》2013
Extensive research carried out in our group on polyphenolic acetates (PAs) substantiated the potential role of PAs in causing diverse biological and pharmacological actions. Our earlier investigations firmly established the calreticulin transacetylase (CRTAase) catalyzed activation of nitric oxide synthase (NOS) by PAs. In this report, we have studied the effect of 7,8-diacetoxy-4-methylcoumarin (DAMC, a model PA) and other acetoxy coumarins on the thioredoxin and VEGF expression in human peripheral blood mononuclear cells (PBMCs), with a view to substantiate our earlier observation that DAMC was a superb inducer of angiogenesis. Real time RT-PCR analysis revealed the enhanced expression of thioredoxin reductase (TRXR) and diminished expression of thioredoxin interacting protein (TRXIP) leading to the increased expression and activity of thioredoxin (TRX) in PBMCs due to the the action of DAMC. The fact that TRX activity of PBMCs was enhanced by various acetoxy coumarins in tune with their affinity to CRTAase as substrate, suggested the possible activation of TRX due to acetylation. The overexpression of thioredoxin was found to correlate with that of VEGF as proved by real time RT-PCR and VEGF -ELISA results, apart from the DAMC-caused enhanced production of NO acting as an inducer of VEGF. Moreover, the intracellular ROS levels were also found to be reduced drastically, by DAMC thus reducing the oxidative stress in cells. These observations strongly evidenced the crucial role of TRX in DAMC-induced tissue angiogenesis with the involvement of VEGF. 相似文献
968.
Sharad S. Singhal James Figarola Jyotsana Singhal Marpadga A. Reddy Xueli Liu David Berz Rama Natarajan Sanjay Awasthi 《The Journal of biological chemistry》2013,288(32):23394-23406
Feeding a Western high-fat diet (HFD) to C57BL/6 mice induces obesity, associated with a chronic inflammatory state, lipid transport, and metabolic derangements, and organ system effects that particularly prominent in the kidneys. Here, we report that RLIP76 homozygous knock-out (RLIP76−/−) mice are highly resistant to obesity as well as these other features of metabolic syndrome caused by HFD. The normal increase in pro-inflammatory and fibrotic markers associated with HFD induced obesity in wild-type C57B mice was broadly and nearly completely abrogated in RLIP76−/− mice. This is a particularly striking finding because chemical markers of oxidative stress including lipid hydroperoxides and alkenals were significantly higher in RLIP76−/− mice. Whereas HFD caused marked suppression of AMPK in wild-type C57B mice, RLIP76−/− mice had baseline activation of AMP-activated protein kinase, which was not further affected by HFD. The baseline renal function was reduced in RLIP76−/− mice as compared with wild-type, but was unaffected by HFD, in marked contrast to severe renal impairment and glomerulopathy in the wild-type mice given HFD. Our findings confirm a fundamental role of RLIP76 in regulating the function of obesity-promoting pro-inflammatory cytokines, and provide a novel mechanism for targeted therapy of obesity and metabolic syndrome. 相似文献
969.
970.
Ruchi Singh Sanjay Ranjan Sanjeeva Nayaka Uday V. Pathre Pramod A. Shirke 《Acta Physiologiae Plantarum》2013,35(5):1605-1615
Stereocaulon foliolosum a fruticose type of lichen under its natural habitat is subjected to low temperature, high light conditions and frequent moisture stress due its rocky substratum. To understand as to how this lichen copes up with these stresses, we studied the reflectance properties, light utilization capacity and the desiccation tolerance under laboratory conditions. S. foliolosum showed light saturation point for photosynthesis at 390 μmol CO2 m?2 s?1 and the light compensation point for photosynthesis at 64 μmol CO2 m?2 s?1. Our experiments show that S. foliolosum has a low absorptivity (30–35 %) towards the incident light. The maximum rates of net photosynthesis and apparent electron transport observed were 1.9 μmol CO2 m?2 s?1 and 45 μmol e? m?2 s?1, respectively. The lichen recovers immediately after photoinhibition under low light conditions. S. foliolosum on subjecting to desiccation results in the decrease of light absorptivity and the reflectance properties associated with water status of the thalli show a change. During desiccation, a simultaneous decrease in photosynthesis, dark respiration and quenching in the fluorescence properties was observed. However, all the observed changes show a rapid recovery on rewetting the lichen. Our study shows that desiccation does not have a severe or long-term impact on S. foliolosum and the lichen is also well adapted to confront high light intensities. 相似文献