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51.
Faramarzi MA Tabatabaei Yazdi M Amini M Zarrini G Shafiee A 《FEMS microbiology letters》2003,222(2):183-186
Microbial hydroxylation of progesterone occurred in the culture of Acremonium strictum PTCC 5282 to produce two hydroxylated pregnene-like steroids. The metabolites were purified and characterized using spectroscopic methods and identified as 15alpha-hydroxyprogesterone and 15alpha-hydroxydeoxycorticosterone. 相似文献
52.
McCulloch CC Kay DM Factor SA Samii A Nutt JG Higgins DS Griffith A Roberts JW Leis BC Montimurro JS Zabetian CP Payami H 《Human genetics》2008,123(3):257-265
The objective of this study was to explore combined effects of four candidate susceptibility genes and two exposures on Parkinson’s
disease (PD) risk; namely, α-synuclein (SNCA) promoter polymorphism REP1, microtubule-associated protein tau (MAPT) H1/H2 haplotypes, apolipoprotein E (APOE) ε2/ε3/ε4 polymorphism, ubiquitin carboxy-terminal esterase L1 (UCHL1) S18Y variant, cigarette smoking and caffeinated coffee consumption. 932 PD patients and 664 control subjects from the NeuroGenetics
Research Consortium, with complete data on all six factors, were studied. Uniform protocols were used for diagnosis, recruitment,
data collection and genotyping. A logistic regression model which included gene-exposure interactions was applied. Likelihood
ratio tests (LRTs) were used for significance testing and Bayesian inference was used to estimate odds ratios (ORs). MAPT (P = 0.007), SNCA REP1 (P = 0.012), smoking (P = 0.001), and coffee (P = 0.011) were associated with PD risk. Two novel interactions were detected: APOE with coffee (P = 0.005), and REP1 with smoking (P = 0.021). While the individual main effects were modest, each yielding OR < 1.6, the effects were cumulative, with some combinations
reaching OR = 12.6 (95% CI: 5.9–26.8). This study provides evidence for the long-held notion that PD risk is modulated by
cumulative and interactive effects of genes and exposures. Furthermore, the study demonstrates that while interaction studies
are useful for exploring risk relationships that might otherwise go undetected, results should be interpreted with caution
because of the inherent loss of power due to multiple testing. The novel findings of this study that warrant replication are
the evidence for interaction of coffee with APOE, and of smoking with REP1 on PD risk.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
53.
Ali Zohaib Muhammad Saqib Muhammad Ammar Athar Jing Chen Awais-ur-Rahman Sial Saeed Khan Zeeshan Taj Halima Sadia Usman Tahir Muhammad Haleem Tayyab Muhammad Asif Qureshi Muhammad Khalid Mansoor Muhammad Ahsan Naeem Bing-Jie Hu Bilal Ahmed Khan Ikram Din Ujjan Bei Li Wei Zhang Yun Luo Yan Zhu Cecilia Waruhiu Iahtasham Khan Xing-Lou Yang Muhammad Sohail Sajid Victor Max Corman Bing Yan Zheng-Li Shi 《中国病毒学》2018,33(5):410-417
Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is a zoonotic pathogen capable of causing severe respiratory disease in humans. Although dromedary camels are considered as a major reservoir host, the MERS-CoV infection dynamics in camels are not fully understood. Through surveillance in Pakistan, nasal (n = 776) and serum (n = 1050)samples were collected from camels between November 2015 and February 2018. Samples were collected from animal markets, free-roaming herds and abattoirs. An in-house ELISA was developed to detect IgG against MERS-CoV. A total of 794 camels were found seropositive for MERS-CoV. Prevalence increased with the age and the highest seroprevalence was recorded in camels aged [ 10 years (81.37%) followed by those aged 3.1–10 years (78.65%) and B 3 years (58.19%).Higher prevalence was observed in female (78.13%) as compared to male (70.70%). Of the camel nasal swabs, 22 were found to be positive by RT-qPCR though with high Ct values. Moreover, 2,409 human serum samples were also collected from four provinces of Pakistan during 2016–2017. Among the sampled population, 840 humans were camel herders.Although we found a high rate of MERS-CoV antibody positive dromedaries (75.62%) in Pakistan, no neutralizing antibodies were detected in humans with and without contact to camels. 相似文献
54.
Ali Alsalme Nabil Al-Zaqri Rizwan Ullah Sidra Yaqub 《Saudi Journal of Biological Sciences》2021,28(3):1757-1762
Present study was designed to obtain estimation about ground water quality of Bhimber, Azad Jammu and Kashmir (AJK), Pakistan. A total of 12 water samples were collected from different localities of study area to analyze for various physicochemical and biological parameters i.e. namely temperature, pH, turbidity, color, odor, taste, electric conductivity (EC), total dissolved solids (TDS), total hardness (Calcium + Magnesium), chloride, arsenic, phosphate, lead, ammonium ion, nitrite, Fecal coliform and Escherichia coli. Results exposed that all ground water samples of study area were grossly contaminated with pathogenic microorganisms like E. coli and Fecal coliform except one water sample that was obtained from community filter plant Samahni Chowk site. Besides it, values of some physicochemical water quality determining parameters also deviated from recommended limits of World Health Organization (WHO). Chloride ion concentration was little below the prescribed limits in almost all water samples. It has been proven that consumption of un-safe drinking water is one of the major cause of prevalence of water borne diseases like diarrhea, gastroenteritis, typhoid fever and malaria etc. in study area. Community water supply and sanitation projects should be encouraged; government should provide filter plants in all regions of the country so that people could have easy approach to safe drinking water. 相似文献
55.
Xu Chang Hong; Nejidat Ali; Belkin Shimshon; Boussiba Sammy 《Plant & cell physiology》1994,35(5):737-741
Partition in aqueous dextran-polyethylene glycol two-phase systemwas used to isolate the plasma membranes from the alkalophiliccyanobacterium Spirulina platensis. The upper phase containeda colorless membranes obtained in relatively short time, 34h. This fraction had a different protein profile than that ofthe thylakoid fraction obtained in the lower phase. It did notcontain cytochrome c-oxidase activity, but retained characteristicMg2+-ATPase activity that is sensitive to vanadate, stimulatedby K+, and has a pH optimum near 8.5. These data support ourassumption that the upper phase of the gradient consist of theplasma membrane of S. platensis. (Received November 25, 1993; Accepted April 12, 1994) 相似文献
56.
Yavuz N Unal E Dogan M Kiziler AR Aydemir B Titiz I 《Biological trace element research》2005,106(3):205-209
Serum free prostate-specific antigen (fPSA) is the most useful tumor marker for prostatic cancer screening. However, recently,
fPSA has also been detected in sera from patients with pancreatic diseases. In addition, it has been shown that zinc (Zn)
concentration might change in both serum and tissues in pancreatic disease. In the present study, we measured serum concentrations
of fPSA and Zn as possible markers and prognostic factors in an experimental acute-pancreatitis model. Twenty-five female
Wistar albino rats were divided into two groups: the control group (n=10) and the experimental group (n=15). Acute pancreatitis was induced by injection of ethyl alcohol into the common biliary duct. The animals were sacrificed
24 h later to detect the concentrations of serum fPSA and Zn. fPSA values were detected to be significantly higher in the
experimental group p<0.001). There was also a significant decrease in the serum Zn level of the acute-pancreatitis group (p<0.001). In conclusion, these findings suggested that a combination of these parameters might represent a significant improvement
on the diagnostic value of each of them separately and provide a powerful tool for differential diagnosis and prognosis in
pancreatic diseases. 相似文献
57.
Campylobacter jejuni adenosine triphosphate phosphoribosyltransferase is an active hexamer that is allosterically controlled by the twisting of a regulatory tail 下载免费PDF全文
Gerd Mittelstädt Gert‐Jan Moggré Santosh Panjikar Ali Reza Nazmi Emily J. Parker 《Protein science : a publication of the Protein Society》2016,25(8):1492-1506
Adenosine triphosphate phosphoribosyltransferase (ATP‐PRT) catalyzes the first committed step of the histidine biosynthesis in plants and microorganisms. Here, we present the functional and structural characterization of the ATP‐PRT from the pathogenic ε‐proteobacteria Campylobacter jejuni (CjeATP‐PRT). This enzyme is a member of the long form (HisGL) ATP‐PRT and is allosterically inhibited by histidine, which binds to a remote regulatory domain, and competitively inhibited by AMP. In the crystalline form, CjeATP‐PRT was found to adopt two distinctly different hexameric conformations, with an open homohexameric structure observed in the presence of substrate ATP, and a more compact closed form present when inhibitor histidine is bound. CjeATP‐PRT was observed to adopt only a hexameric quaternary structure in solution, contradicting previous hypotheses favoring an allosteric mechanism driven by an oligomer equilibrium. Instead, this study supports the conclusion that the ATP‐PRT long form hexamer is the active species; the tightening of this structure in response to remote histidine binding results in an inhibited enzyme. 相似文献
58.
K. Sapna P. P. Manzur Ali K. R. Rekha Mol Sarita G. Bhat M. Chandrasekaran K. K. Elyas 《Biotechnology letters》2017,39(12):1911-1916
Objectives
An extracellular protease inhibitor (BTPI-301) of trypsin was purified and characterized from an isolate of Pseudomonas mendocina.Results
BTPI-301was purified to homogeneity by (NH4)2SO4, precipitation, DEAE Sepharose and CNBr-activated Sepharose chromatography. Homogeneity was proved by native PAGE and SDS-PAGE. The intact molecular mass was 11567 Da by MALDI-TOF analysis. BTPI-301was a competitive inhibitor with a Ki of 3.5 × 10?10 M. It was stable and active at pH 4–12 and also at 4–90 °C for 1 h. Peptide mass fingerprinting by MALDI revealed that the BTPI-301 is a new inhibitor not reported so far with protease inhibitory activity. The pI of the inhibitor was 3.8. The stoichiometry of trypsin-BTPI-301 interaction is 1:1. The inhibitor was specific towards trypsin.Conclusion
A pH tolerant and thermostable protease inhibitor BTPI-301 active against trypsin was purified and characterized from P. mendocina that could be developed and used as biopreservative as well as biocontrol agent.59.
Ali NA Gaughan AA Orosz CG Baran CP McMaken S Wang Y Eubank TD Hunter M Lichtenberger FJ Flavahan NA Lawler J Marsh CB 《PloS one》2008,3(4):e1914
Latency Associated Peptide (LAP) binds TGF-beta1, forming a latent complex. Currently, LAP is presumed to function only as a sequestering agent for active TGF-beta1. Previous work shows that LAP can induce epithelial cell migration, but effects on leukocytes have not been reported. Because of the multiplicity of immunologic processes in which TGF-beta1 plays a role, we hypothesized that LAP could function independently to modulate immune responses. In separate experiments we found that LAP promoted chemotaxis of human monocytes and blocked inflammation in vivo in a murine model of the delayed-type hypersensitivity response (DTHR). These effects did not involve TGF-beta1 activity. Further studies revealed that disruption of specific LAP-thrombospondin-1 (TSP-1) interactions prevented LAP-induced responses. The effect of LAP on DTH inhibition depended on IL-10. These data support a novel role for LAP in regulating monocyte trafficking and immune modulation. 相似文献
60.
Shah HN Rajakaruna L Ball G Misra R Al-Shahib A Fang M Gharbia SE 《Systematic and applied microbiology》2011,34(1):81-86
Strains (n = 99) of Staphylococcus aureus isolated from a large number of clinical sources and tested for methicillin sensitivity were analysed by MALDI-TOF-MS using the Weak Cation Exchange (CM10) ProteinChip Array (designated SELDI-TOF-MS). The profile data generated was analysed using Artificial Neural Network (ANN) Analysis modelling techniques. Seven key ions identified by the ANNs that were predictive of MRSA and MSSA were validated by incorporation into a model. This model exhibited an area under the ROC curve value of 0.9147 indicating the potential application of this approach for rapidly characterising MRSA and MSSA isolates. Nearly all strains (n = 97) were correctly assigned to the correct group, with only two aberrant MSSA strains being misclassified. However, approximately 21% of the strains appeared to be in a process of transition as resistance to methicillin was being acquired. 相似文献