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131.
Shaik Mohammad Naushad Akella Radha Rama Devi Sriraman Nivetha Ganapathy Lakshmitha Alex Balraj Stanley Tajamul Hussain Vijay Kumar Kutala 《Journal of genetics》2017,96(6):919-926
In view of well-documented association of hyperhomocysteinaemia with a wide spectrum of diseases and higher incidence of vitamin deficiencies in Indians, we proposed a mathematical model to forecast the role of demographic and genetic variables in influencing homocysteine metabolism and investigated the influence of life style modulations in controlling homocysteine levels. Total plasma homocysteine levels were measured in fasting samples using reverse phase HPLC. Multiple linear regression (MLR) and neuro-fuzzy models were developed. The MLR model explained 64% variability in homocysteine, while the neuro-fuzzy model showed higher accuracy in predicting homocysteine with a mean absolute error of 0.00002 \(\mu \hbox {mol}/\hbox {L}\). Methylene tetrahydrofolate reductase (MTHFR) C677T, 5-methyltetrahydrofolate homocysteine methyltransferase (MTR) A2756G and 5-methyltetrahydrofolate homocysteine methyltransferase reductase (MTRR) A66G were shown to be positively associatiated with homocysteine, while nonvegetarian diet, serine hydroxymethyltransferase 1 (SHMT1) C1420T and TYMS \(5^\prime \)-UTR 28 bp tandem repeat exhibited negative association with homocysteine. The protective role of SHMT1 C1420T was attributed to more H-bonding interactions in the mutant modelled compared to the wild type, as shown through in silico analysis. To conclude, polymorphisms in genes regulating remethylation of homocysteine strongly influence homocysteine levels. The restoration of one-carbon homeostasis by SHMT1 C1420T or increased flux of folate towards remethylation due to TYMS \(5^\prime \)-UTR 28 bp tandem repeat or nonvegetarian diet can lower homocysteine levels. 相似文献
132.
Impact of Monovalent Cation Halide Additives on the Structural and Optoelectronic Properties of CH3NH3PbI3 Perovskite 下载免费PDF全文
Mojtaba Abdi‐Jalebi M. Ibrahim Dar Aditya Sadhanala Satyaprasad P. Senanayak Marius Franckevičius Neha Arora Yuanyuan Hu Mohammad Khaja Nazeeruddin Shaik M. Zakeeruddin Michael Grätzel Richard H. Friend 《Liver Transplantation》2016,6(10)
The influence of monovalent cation halide additives on the optical, excitonic, and electrical properties of CH3NH3PbI3 perovskite is reported. Monovalent cation halide with similar ionic radii to Pb2+, including Cu+, Na+, and Ag+, have been added to explore the possibility of doping. Significant reduction of sub‐bandgap optical absorption and lower energetic disorder along with a shift in the Fermi level of the perovskite in the presence of these cations has been observed. The bulk hole mobility of the additive‐based perovskites as estimated using the space charge limited current method exhibits an increase of up to an order of magnitude compared to the pristine perovskites with a significant decrease in the activation energy. Consequentially, enhancement in the photovoltaic parameters of additive‐based solar cells is achieved. An increase in open circuit voltage for AgI (≈1.02 vs 0.95 V for the pristine) and photocurrent density for NaI‐ and CuBr‐based solar cells (≈23 vs 21 mA cm?2 for the pristine) has been observed. This enhanced photovoltaic performance can be attributed to the formation of uniform and continuous perovskite film, better conversion, and loading of perovskite, as well as the enhancement in the bulk charge transport along with a minimization of disorder, pointing towards possible surface passivation. 相似文献
133.
Reham
H. Baaqeel Babajan Banaganapalli Hadiah
Bassam Al Mahdi Mohammed
A. Salama Bakr
H. Alhussaini Meshari
A. Alaifan Yagoub Bin-Taleb Noor
Ahmad Shaik Jumana
Yousuf Al-Aama Ramu Elango Omar
I. Saadah 《Bioscience reports》2021,41(6)
Background: Celiac disease (CD) is a genetically complex autoimmune disease which is triggered by dietary gluten. Human leukocyte antigen (HLA) class II genes are known to act as high-risk markers for CD, where >95% of CD patients carry (HLA), DQ2 and/or DQ8 alleles. Therefore, the present study was conducted to investigate the distribution of HLA haplotypes among Saudi CD patients and healthy controls by using the tag single nucleotide polymorphisms (SNP).Methods: HLA-tag SNPs showing strong linkage value (r2>0.99) were used to predict the HLA DQ2 and DQ8 genotypes in 101 Saudi CD patients and in 103 healthy controls by using real-time polymerase chain reaction technique. Genotype calls were further validated by Sanger sequencing method.Results: A total of 63.7% of CD cases and of 60.2% of controls were predicted to carry HLA-DQ2 and DQ8 heterodimers, either in the homozygous or heterozygous states. The prevalence of DQ8 in our CD patients was predicted to be higher than the patients from other ethnic populations (35.6%). More than 32% of the CD patients were found to be non-carriers of HLA risk haplotypes as predicted by the tag SNPs.Conclusion: The present study highlights that the Caucasian specific HLA-tag SNPs would be of limited value to accurately predict CD specific HLA haplotypes in Saudi population, when compared with the Caucasian groups. Prediction of risk haplotypes by tag SNPs in ethnic groups is a good alternate approach as long as the tag SNPs were identified from the local population genetic variant databases. 相似文献
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135.
Yaser Hassan Dewir Nisha Singh Shakira Shaik Ashley Nicholas 《In vitro cellular & developmental biology. Plant》2010,46(1):41-46
The present study reports a simple protocol for indirect shoot organogenesis and plant regeneration of Sutherlandia using rachis and stem segments. Different concentrations (0.0–68.08 μmol l−1) of thidiazuron (TDZ) were used for callus induction and shoot organogenesis. The highest percentage of callus formation
(97.5%) and the highest percentage of explants forming shoots (88.8%) were obtained from rachis explants cultured onto Murashige
and Skoog (MS) medium (Murashige and Skoog, Physiol. Plant. 15:473–495, 1962) supplemented with 45.41 μmol l−1 TDZ. Scanning electron microscopy demonstrated the early development of adventitious shoots derived from callus cultures.
Shoot clusters were further developed and grown in MS hormone-free medium. The presence of l-canavanine was determined by thin-layer chromatography and confirmed after column fractionation using silica gel and nuclear
magnetic resonance spectroscopy. Individual shoots were rooted on different concentrations and combinations of MS salt strength
and IBA. Half-strength MS salt medium supplemented with 24.6 μmol l−1 IBA was optimal for root induction in which 78% of shoots were rooted. The in vitro plants were successfully acclimatized in a growth chamber with a 90% survival rate. 相似文献
136.
Shaik Mohammad Naushad Tajamul Hussain Omar S. Al-Attas Aruna Prayaga Raghunadha Rao Digumarti Suryanarayana Raju Gottumukkala Vijay Kumar Kutala 《Molecular and cellular biochemistry》2014,392(1-2):273-280
Obesity, genetic polymorphisms of xenobiotic metabolic pathway, hypermethylation of tumor suppressor genes, and hypomethylation of proapoptotic genes are known to be independent risk factors for breast cancer. The objective of this study is to evaluate the combined effect of these environmental, genetic, and epigenetic risk factors on the susceptibility to breast cancer. PCR–RFLP and multiplex PCR were used for the genetic analysis of six variants of xenobiotic metabolic pathway. Methylation-specific PCR was used for the epigenetic analysis of four genetic loci. Multifactor dimensionality reduction analysis revealed a significant interaction between the body mass index (BMI) and catechol-O-methyl transferase H108L variant alone or in combination with cytochrome P450 (CYP) 1A1m1 variant. Women with “Luminal A” breast cancer phenotype had higher BMI compared to other phenotypes and healthy controls. There was no association between the BMI and tumor grade. The post-menopausal obese women exhibited lower glutathione levels. BMI showed a positive association with the methylation of extracellular superoxide dismutase (r = 0.21, p < 0.05), Ras-association (RalGDS/AF-6) domain family member 1 (RASSF1A) (r = 0.31, p < 0.001), and breast cancer type 1 susceptibility protein (r = 0.19, p < 0.05); and inverse association with methylation of BNIP3 (r = ?0.48, p < 0.0001). To conclude based on these results, obesity increases the breast cancer susceptibility by two possible mechanisms: (i) by interacting with xenobiotic genetic polymorphisms in inducing increased oxidative DNA damage and (ii) by altering the methylome of several tumor suppressor genes. 相似文献
137.
Kyung-Bin Cho Wenzhen Lai Mats Hamberg C.S. Raman Sason Shaik 《Archives of biochemistry and biophysics》2011,507(1):81
A combined theoretical and experimental study highlights the reaction mechanism of allene oxide synthase (AOS) and its possible link to hydroperoxide lyase (HPL) pathway. A previously published study (Lee et al., Nature 455 (2008) 363) has shown that the F137 residue is of central importance in differentiating between the AOS and HPL pathways after initial identical steps. In the experimental part of this study, we show that wild-type AOS from Arabidopsis or rice in fact produces both AOS and HPL products in a ratio of about 80:15, something that was found only in trace amounts before. Theoretical calculations successfully map the whole AOS pathway with 13(S)-hydroperoxy linolenic and linoleic acid as substrates. Subsequent calculations investigated the effects of in silico F137L mutation at the suggested diverging point of the two pathways. The results show that QM/MM calculations can reasonably reproduce three out of four experimentally available cases, and confirm that the pathways are energetically very close to each other, thus making a switch from one path to other plausible under different circumstances. 相似文献
138.
Background and Aims
Nonalcoholic fatty liver disease (NALFD) is a leading cause of liver disease. Weight loss improves clinical features of NAFLD; however, maintenance of weight loss outside of investigational protocols is poor. The goals of this study were to characterize patterns and clinical predictors of long-term weight loss in ambulatory patients with NAFLD.Methods
We retrospectively reviewed 924 non-cirrhotic patients with NAFLD presenting to a liver clinic from May 1st 2007 to April 30th 2013. Overweight and obese patients were counseled on lifestyle modifications for weight loss as per USPSTF guidelines. The primary outcome was percent weight change between the first and last recorded visits: % weight change = (weightinitial – weightfinal)/(weightinitial). Baseline BMI and percent BMI change were secondary measures. Predictors of weight loss were determined using logistic regression.Results
The mean baseline BMI was 33.3±6.6 kg/m2, and the mean follow-up duration was 17.3±17.6 months. Most patients with NAFLD were in either overweight (26.1%) or class I obesity (30.5%) categories at baseline, while the prevalence of underweight and class III obesity was lower (0.2% and 15.4%, respectively). Overall, there was no change in mean weight or BMI during the follow-up period, and only 183 patients (19.8%) lost at least 5% body weight during the follow up period. Independent predictors of weight loss included number of clinic visits and baseline BMI, and patients with higher baseline BMI required more clinic visits to lose weight.Conclusions
Weight loss is largely unsuccessful in NAFLD patients in the ambulatory care setting. Frequent clinical encounters are associated with weight reduction, especially among individuals with high baseline BMI. Future studies are required to define effective weight loss strategies in NAFLD patients. 相似文献139.
Shaik S de Visser SP Ogliaro F Schwarz H Schröder D 《Current opinion in chemical biology》2002,6(5):556-567
Recent computational studies of alkane hydroxylation and alkene epoxidation by a model active species of the enzyme cytochrome P-450 reveal a two-state reactivity (TSR) scenario in which the information content of the product distribution is determined jointly by two states. TSR is used to reconcile the dilemma of the consensus 'rebound mechanism' of alkane hydroxylation, which emerged from experimental studies of ultra-fast radical clocks. The dilemma, stated succinctly as 'radicals are both present and absent and the rebound mechanism is both right and wrong', is simply understood once one is cognizant that the mechanism operates by two states, one low-spin (LS) the other high-spin (HS). In both states, bond activation proceeds in a manner akin to the rebound mechanism, but the LS mechanism is effectively concerted, whereas the HS is stepwise with incursion of radical intermediates. 相似文献
140.
Lavanya Nagamalla J.V. Shanmukha Kumar Chintakindi Sanjay Ali M Alsamhan Mohammed Rafi Shaik 《Saudi Journal of Biological Sciences》2022,29(2):689-701
AXL kinase is an attractive cancer target for drug design and it is involved in different cancers. A set of molecule databases with 1072 secondary metabolites from seaweeds were screened against the AXL kinase active site and eight molecules were shortlisted for further studies. From the docking analysis of the complexes, four molecules GA011, BE005, BC010, and BC005 are showing prominent binging. From the 100 ns of molecular dynamics simulations and ligand-bound complex MM-PBSA free energy analysis, two molecules BC010 (ΔG = −135.38 kJ/mol) and BE005 (ΔG = −141.72 kJ/mol) are showing molecule stability in the active site also showing very strong binding free energies. It suggests these molecules could be the potent molecules for AXL kinase. 相似文献