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981.
The gene encoding the glycine oxidase from Bacillus subtilis strain R5 (goxR) was cloned and expressed in Escherichia coli. The gene consisted of 1,110 nucleotides that encoded a protein (GoxR) of 369 amino acid residues with a molecular mass of
40,761 Da. The GoxR exhibited 98.6% identity with glycine oxidase from B. subtilis strain 168. Gene expression and purification of the recombinant GoxR were performed. The recombinant GoxR existed in a homotetramer
form. The recombinant protein effectively catalyzed the oxidation of glycine and d-alanine. The specific activity of the purified recombinant GoxR was 0.96 U/mg when glycine was used as a substrate and 1.0
U/mg when d-alanine was substrate. The enzyme displayed its highest activity at pH 8.0 and at a temperature of 50°C. The activation energy
of the reaction catalyzed by the enzyme was calculated to be 26 kJ/mol. The enzyme activity was significantly inhibited in
the presence of organic solvents. No enhancement of enzyme activity was observed in the presence of metal cations. The experimental
results presented in this study demonstrate that the enzyme was a bonafide glycine oxidase. 相似文献
982.
A gene encoding the xylanase from Bacillus subtilis strain R5 containing the native signal sequence was cloned and expressed in Escherichia coli. The heterologous expression of the gene resulted in the production of the recombinant protein in the cytoplasm as well as
its secretion into the culture medium. The xylanase activity in the culture medium increased with time after induction up
to 90% of the total activity in 14 h. Molecular mass and N-terminal amino acid sequence determinations of the purified recombinant
xylanase revealed that the native signal peptide was cleaved off by E. coli signal peptidases between Ala28 and Ala29. 相似文献
983.
Human papillomavirus (HPV) is the most common sexually transmitted viral infection worldwide. HPV tumorigenesis genotypes are the causative agents of cervical cancer and genital malignancies. The scientific literature has demonstrated that life style, environmental, epigenetic accompanied with HR-HPV genotypes are potential risk factors for cervical cancer progression. The frequencies of the Cyp2C9*2, Cyp2C9*3, and vitamin K epoxide reductase complex subunit 1 (VKORC1) genotypes as potential molecular biomarkers have been investigated on Iranian women with cervical malignancy related to HPV genotypes. As a case-control study, the mutations were appraised using a polymerase chain reaction-restriction fragment length polymorphism procedure on women suffering from HPV infection (60 cases), CC (46 cases), and 40 subjects of as healthy control. The outcomes demonstrated that Cyp2C9*3 showed a meaningful relationship between women diagnosed with cervical cancer and the healthy population (AA vs. AC; OR, 7.15; 95% CI, 1.94-26.3; p = .003). It was also observed that the Cyp2C9*3 mutation in women with cervical cancer and VKORC1 in healthy population with HPV (+), did not follow the Hardy–Weinberg equilibrium. Our findings aid understanding the genetic polymorphism distribution of Cyp2C9*2, Cyp2C9*3, and VKORC1 in women with genital malignancies. This can also be useful in predicting the susceptibility risk factors for developing cervical cancer. However, allelic discrimination as a molecular biomarker requires further research. 相似文献
984.
Atapour Amir Negahdaripour Manica Ghasemi Younes Razmjuee Dorna Savardashtaki Amir Mousavi Seyyed Mojtaba Hashemi Seyyed Alireza Aliabadi Ali Nezafat Navid 《International journal of peptide research and therapeutics》2020,26(1):369-380
International Journal of Peptide Research and Therapeutics - Breast cancer (BC) is the most common type of women’s cancer with a prevalence of about 25%, although it is rare in men... 相似文献
985.
Yi Zhang Min Chen Yuanyuan Zhou Wenhao Li Yonghui Lee Hiroyuki Kanda Xiao‐Xin Gao Ruiyuan Hu Keith Gregory Brooks Rashid Zia Sachin Kinge Nitin P. Padture Mohammad Khaja Nazeeruddin 《Liver Transplantation》2020,10(29)
Composition and film quality of perovskite are crucial for the further improvement of perovskite solar cells (PSCs), including efficiency, reproducibility, and stability. Here, it is demonstrated that by simply mixing 50% of formamidinium (FA+) into methylammonium lead iodide (MAPbI3), a highly crystalline, stable phase, and compact, polycrystalline grain morphology perovskite is formed by using a solvent‐mediated phase transformation process via the synergism of dimethyl sulfoxide and diethyl ether, which shows long carrier lifetime, low trap state density, and a record certified 21.8% power conversion efficiency (PCE) in pure‐iodide, alkaline‐metal‐free MA0.5FA0.5PbI3 perovskite‐based PSCs. These PSCs show very high operational stability, with 85% PCE retention upon 1000 h 1 Sun intensity illumination. A 17.33% PCE module (6.5 × 7 cm2) is also demonstrated, attesting to the scalability of such devices. 相似文献
986.
Background
Sepsis causes extensive morbidity and mortality in children worldwide. Prompt recognition and timely treatment of sepsis is critical in reducing morbidity and mortality. Genomic approaches are used to discover novel pathways, therapeutic targets and biomarkers. These may facilitate diagnosis and risk stratification to tailor treatment strategies.Objective
To investigate the temporal gene expression during the evolution of sepsis induced multi-organ failure in response to a single organism, Neisseria meningitidis, in previously healthy children.Method
RNA was extracted from serial blood samples (6 time points over 48 hours from presentation) from five critically ill children with meningococcal sepsis. Extracted RNA was hybridized to Affymetrix arrays. The RNA underwent strict quality control and standardized quantitation. Gene expression results were analyzed using GeneSpring software and Ingenuity Pathway Analysis.Result
A marked variability in differential gene expression was observed between time points and between patients revealing dynamic expression changes during the evolution of sepsis. While there was evidence of time-dependent changes in expected gene networks including those involving immune responses and inflammatory pathways, temporal variation was also evident in specific “biomarkers” that have been proposed for diagnostic and risk stratification functions. The extent and nature of this variability was not readily explained by clinical phenotype.Conclusion
This is the first study of its kind detailing extensive expression changes in children during the evolution of sepsis. This highlights a limitation of static or single time point biomarker estimation. Serial estimations or more comprehensive network approaches may be required to optimize risk stratification in complex, time-critical conditions such as evolving sepsis. 相似文献987.
Background
The tolerogenic peptide, hCDR1, ameliorated manifestations of systemic lupus erythematosus (SLE) via the immunomodulation of pro-inflammatory and immunosuppressive cytokines and the induction of regulatory T cells. Because type I interferon (IFN-α) has been implicated to play a role in SLE pathogenesis, we investigated the effects of hCDR1 on IFN-α in a murine model of SLE and in human lupus.Methodology/Principal Findings
(NZBxNZW)F1 mice with established SLE were treated with hCDR1 (10 weekly injections). Splenocytes were obtained for gene expression studies by real-time RT-PCR. hCDR1 down-regulated significantly IFN-α gene expression (73% inhibition compared to vehicle treated mice, p = 0.002) in association with diminished clinical manifestations. Further, hCDR1 reduced, in vitro, IFN-α gene expression in peripheral blood mononuclear cells (PBMC) of 10 lupus patients (74% inhibition compared to medium, p = 0.002) but had no significant effects on the expression levels of IFN-α in PBMC of primary anti-phospholipid syndrome patients or of healthy controls. Lupus patients were treated for 24 weeks with hCDR1 (5) or placebo (4) by weekly subcutaneous injections. Blood samples collected, before and after treatment, were frozen until mRNA isolation. A significant reduction in IFN-α was determined in hCDR1 treated patients (64.4% inhibition compared to pretreatment expression levels, p = 0.015). No inhibition was observed in the placebo treated patients. In agreement, treatment with hCDR1 resulted in a significant decrease of disease activity. IFN-α appears to play a role in the mechanism of action of hCDR1 since recombinant IFN-α diminished the immunomodulating effects of hCDR1 on IL-1β, TGFβ and FoxP3 gene expression.Conclusions/Significance
We reported previously that hCDR1 affected various cell types and immune pathways in correlation to disease amelioration. The present studies demonstrate that hCDR1 is also capable of down-regulating significantly (and specifically to lupus) IFN-α gene expression. Thus, hCDR1 has a potential role as a novel, disease specific treatment for lupus. 相似文献988.
Alexander Frizell Santillo Johanna M?rtensson Olof Lindberg Markus Nilsson Amir Manzouri Maria Landqvist Wald? Danielle van Westen Lars-Olof Wahlund Jimmy L?tt Christer Nilsson 《PloS one》2013,8(7)
MRI diffusion tensor imaging (DTI) studies of white matter integrity in behavioral variant frontotemporal dementia have consistently shown involvement of frontal and temporal white matter, corresponding to regional loss of cortical volume. Volumetric imaging has a suboptimal sensitivity as a diagnostic tool and thus we wanted to explore if DTI is a better method to discriminate patients and controls than volumetric imaging. We examined the anterior cingulum bundle in 14 patients with behavioral variant frontotemporal dementia and 22 healthy controls using deterministic manual diffusion tensor tractography, and compared DTI parameters with two measures of cortical atrophy, VBM and cortical thickness, of the anterior cingulate cortex (ACC). Statistically significant changes between patients and controls were detected in all DTI parameters, with large effect sizes. ROC-AUC was for the best DTI parameters: 0.92 (fractional anisotropy) to 0.97 (radial diffusivity), 0.82 for the best cortical parameter, VBM of the ACC. Results from the AUC were confirmed with binary logistic regression analysis including demographic variables, but only for fractional anisotropy and mean diffusivity. Ability to classify patient/nonpatient status was significantly better for mean diffusivity vs. VBM (p=0.031), and borderline significant for fractional anisotropy vs. VBM (p=0.062). The results indicate that DTI could offer advantages in comparison with the assessment of cortical volume in differentiating patients with behavioral variant frontotemporal dementia and controls. 相似文献
989.
990.
Overfishing threatens coral reefs worldwide, yet there is no reliable estimate on the number of reef fishers globally. We address this data gap by quantifying the number of reef fishers on a global scale, using two approaches - the first estimates reef fishers as a proportion of the total number of marine fishers in a country, based on the ratio of reef-related to total marine fish landed values. The second estimates reef fishers as a function of coral reef area, rural coastal population, and fishing pressure. In total, we find that there are 6 million reef fishers in 99 reef countries and territories worldwide, of which at least 25% are reef gleaners. Our estimates are an improvement over most existing fisher population statistics, which tend to omit accounting for gleaners and reef fishers. Our results suggest that slightly over a quarter of the world’s small-scale fishers fish on coral reefs, and half of all coral reef fishers are in Southeast Asia. Coral reefs evidently support the socio-economic well-being of numerous coastal communities. By quantifying the number of people who are employed as reef fishers, we provide decision-makers with an important input into planning for sustainable coral reef fisheries at the appropriate scale. 相似文献