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991.
OX40 and OX40L, members of the tumor necrosis factor receptor superfamily, are costimulatory molecules involved in the activation and proliferation of T lymphocytes. OX40L plays an important role in the process of atherosclerosis, and variants of OX40/OX40L are associated with myocardial infarction in European populations. Our study examined 235 patients with acute coronary syndrome (ACS) and 220 controls and sought to establish whether polymorphisms in OX40/OX40L are associated with atherosclerosis or myocardial infarction in the Han Chinese population. OX40 rs17568A/G, rs2298212A/G, and OX40L rs3850641A/G polymorphisms were genotyped using the polymerase chain reaction-restriction fragment length polymorphism method. The results showed that carriers of the G allele of rs17568A/G had a significantly increased risk of ACS (p?=?0.023, adjusted odds ratio?=?1.72, 95% confidence interval?=?1.08-2.75) after adjusting for age, sex, diabetes, hypertension, and lipids. No significant association between rs2298212A/G or rs3850641A/G and the risk of ACS was found in this study. In conclusion, OX40 gene polymorphism may be associated with a risk of ACS in the Han Chinese population, although the association between OX40L polymorphisms and ACS requires further investigation. 相似文献
992.
Ding R Wu XC Qian CD Teng Y Li O Zhan ZJ Zhao YH 《Journal of microbiology (Seoul, Korea)》2011,49(6):942-949
Two lipopeptide antibiotics, pelgipeptins C and D, were isolated from Paenibacillus elgii B69 strain. The molecular masses of the two compounds were both determined to be 1,086 Da. Mass-spectrometry, amino acid
analysis and NMR spectroscopy indicated that pelgipeptin C was the same compound as BMY-28160, while pelgipeptin D was identified
as a new antibiotic of the polypeptin family. These two peptides were active against all the tested microorganisms, including
antibiotic-resistant pathogenic bacterial strains such as methicillin-resistant Staphylococcus aureus (MRSA). Time-kill assays demonstrated that pelgipeptin D exhibited rapid and effective bactericidal action against MRSA at
4×MIC. Based on acute toxicity test, the intraperitoneal LD50 value of pelgipeptin D was slightly higher than that of the
structurally related antimicrobial agent polymyxin B. Pelgipeptins are highly potent antibacterial and antifungal agents,
particularly against MRSA, and warrant further investigation as possible therapeutic agents for bacteria infections resistant
to currently available antibiotics. 相似文献
993.
Konaté AT Yaro JB Ouédraogo AZ Diarra A Gansané A Soulama I Kangoyé DT Kaboré Y Ouédraogo E Ouédraogo A Tiono AB Ouédraogo IN Chandramohan D Cousens S Milligan PJ Sirima SB Greenwood B Diallo DA 《PLoS medicine》2011,8(2):e1000408
Background
Intermittent preventive treatment of malaria in children (IPTc) is a promising new approach to the control of malaria in areas of seasonal malaria transmission but it is not known if IPTc adds to the protection provided by an insecticide-treated net (ITN).Methods and Findings
An individually randomised, double-blind, placebo-controlled trial of seasonal IPTc was conducted in Burkina Faso in children aged 3 to 59 months who were provided with a long-lasting insecticide-treated bednet (LLIN). Three rounds of treatment with sulphadoxine pyrimethamine plus amodiaquine or placebos were given at monthly intervals during the malaria transmission season. Passive surveillance for malaria episodes was established, a cross-sectional survey was conducted at the end of the malaria transmission season, and use of ITNs was monitored during the intervention period. Incidence rates of malaria were compared using a Cox regression model and generalized linear models were fitted to examine the effect of IPTc on the prevalence of malaria infection, anaemia, and on anthropometric indicators. 3,052 children were screened and 3,014 were enrolled in the trial; 1,505 in the control arm and 1,509 in the intervention arm. Similar proportions of children in the two treatment arms were reported to sleep under an LLIN during the intervention period (93%). The incidence of malaria, defined as fever or history of fever with parasitaemia ≥5,000/µl, was 2.88 (95% confidence interval [CI] 2.70–3.06) per child during the intervention period in the control arm versus 0.87 (95% CI 0.78–0.97) in the intervention arm, a protective efficacy (PE) of 70% (95% CI 66%–74%) (p<0.001). There was a 69% (95% CI 6%–90%) reduction in incidence of severe malaria (p = 0.04) and a 46% (95% CI 7%–69%) (p = 0.03) reduction in the incidence of all-cause hospital admissions. IPTc reduced the prevalence of malaria infection at the end of the malaria transmission season by 73% (95% CI 68%–77%) (p<0.001) and that of moderately severe anaemia by 56% (95% CI 36%–70%) (p<0.001). IPTc reduced the risks of wasting (risk ratio [RR] = 0.79; 95% CI 0.65–1.00) (p = 0.05) and of being underweight (RR = 0.84; 95% CI 0.72–0.99) (p = 0.03). Children who received IPTc were 2.8 (95% CI 2.3–3.5) (p<0.001) times more likely to vomit than children who received placebo but no drug-related serious adverse event was recorded.Conclusions
IPT of malaria provides substantial protection against malaria in children who sleep under an ITN. There is now strong evidence to support the integration of IPTc into malaria control strategies in areas of seasonal malaria transmission.Trial Registration
ClinicalTrials.gov Please see later in the article for the Editors'' Summary NCT00738946相似文献994.
Cellitti SE Ou W Chiu HP Grünewald J Jones DH Hao X Fan Q Quinn LL Ng K Anfora AT Lesley SA Uno T Brock A Geierstanger BH 《Nature chemical biology》2011,7(8):528-530
D-ornithine has previously been suggested to enhance the expression of pyrrolysine-containing proteins. We unexpectedly discovered that uptake of D-ornithine results in the insertion of a new amino acid, pyrroline-carboxy-lysine (Pcl) instead of the anticipated pyrrolysine (Pyl). Our feeding and biochemical studies point to specific roles of the poorly understood Pyl biosynthetic enzymes PylC and PylD in converting L-lysine and D-ornithine to Pcl and confirm intermediates in the biosynthesis of Pyl. 相似文献
995.
Wang Y Fisher JC Mathew R Ou L Otieno S Sublet J Xiao L Chen J Roussel MF Kriwacki RW 《Nature chemical biology》2011,7(4):214-221
Traditionally, well-defined three-dimensional structure has been thought to be essential for protein function. However, myriad biological functions are performed by highly dynamic, intrinsically disordered proteins (IDPs). IDPs often fold upon binding their biological targets and frequently show 'binding diversity' by targeting multiple ligands. We sought to understand the physical basis of IDP binding diversity and report here that the cyclin-dependent kinase (Cdk) inhibitor p21(Cip1) adaptively binds to and inhibits the various Cdk-cyclin complexes that regulate eukaryotic cell division. Using results from NMR spectroscopy and biochemical and cellular assays, we show that structural adaptability of a helical subdomain within p21, termed LH, enables two other subdomains, D1 and D2, to specifically bind conserved surface features of the cyclin and Cdk subunits, respectively, within otherwise structurally distinct Cdk-cyclin complexes. Adaptive folding upon binding is likely to mediate the diverse biological functions of the thousands of IDPs present in eukaryotes. 相似文献
996.
997.
Lee Kozakiewicz Yong Chen Jiayong Xu Yanhua Wang Kyri Dunussi-Joannopoulos Qinglin Ou Joanne L. Flynn Steven A. Porcelli William R. Jacobs Jr John Chan 《PLoS pathogens》2013,9(7)
We have previously demonstrated that B cells can shape the immune response to Mycobacterium tuberculosis, including the level of neutrophil infiltration and granulomatous inflammation at the site of infection. The present study examined the mechanisms by which B cells regulate the host neutrophilic response upon exposure to mycobacteria and how neutrophilia may influence vaccine efficacy. To address these questions, a murine aerosol infection tuberculosis (TB) model and an intradermal (ID) ear BCG immunization mouse model, involving both the μMT strain and B cell-depleted C57BL/6 mice, were used. IL (interleukin)-17 neutralization and neutrophil depletion experiments using these systems provide evidence that B cells can regulate neutrophilia by modulating the IL-17 response during M. tuberculosis infection and BCG immunization. Exuberant neutrophilia at the site of immunization in B cell-deficient mice adversely affects dendritic cell (DC) migration to the draining lymph nodes and attenuates the development of the vaccine-induced Th1 response. The results suggest that B cells are required for the development of optimal protective anti-TB immunity upon BCG vaccination by regulating the IL-17/neutrophilic response. Administration of sera derived from M. tuberculosis-infected C57BL/6 wild-type mice reverses the lung neutrophilia phenotype in tuberculous μMT mice. Together, these observations provide insight into the mechanisms by which B cells and humoral immunity modulate vaccine-induced Th1 response and regulate neutrophila during M. tuberculosis infection and BCG immunization. 相似文献
998.
Noëllie W. Kpoda Herman Sorgho Jean-Noël Poda Jean Bosco Ouédraogo Gustave B. Kabré 《Comptes rendus biologies》2013,336(5-6):284-288
Schistosomiasis is one of the waterborne diseases which benefit from environmental and behavioral changes induced by the mobilization of surface water resources in Sahelian countries, such as Burkina Faso. Studies have established the existence of human schistosomiasis in the Kou valley, one of the oldest hydro-agricultural zones in the country. However, the role of population behavior in the transmission pattern of this disease and its socioeconomic impact in this valley are poorly understood. It is in response to these questions that this study was undertaken. The objectives of this study were to identify activities that exposed most of the Valley's population to infection by schistosomiasis, and to contribute knowledge on the consequences of this disease. The study was conducted in the cold dry season at the Kou Valley, located in the South Sudanese area of Burkina Faso. It has adopted the strategy of direct observation to examine host–parasites interactions. The study of the socioeconomic consequences of the infection has been first to identify subjects that actually carry the parasite by screening the population by the Kato–Katz method. These were then subjected to a questionnaire. Data were analyzed using Epi Info 6.4. This work has revealed six activities at risk of infection for the residents of the Valley with an increased risk of factor for rice farming, household activities and swimming. In view of these activities, women and young people seem to be most vulnerable to infection. This disease causes significant economic losses as a function of socio-professional categories of infected persons. 相似文献
999.
Background
Cellular respiration is the process by which cells obtain energy from glucose and is a very important biological process in living cell. As cells do cellular respiration, they need a pathway to store and transport electrons, the electron transport chain. The function of the electron transport chain is to produce a trans-membrane proton electrochemical gradient as a result of oxidation–reduction reactions. In these oxidation–reduction reactions in electron transport chains, metal ions play very important role as electron donor and acceptor. For example, Fe ions are in complex I and complex II, and Cu ions are in complex IV. Therefore, to identify metal-binding sites in electron transporters is an important issue in helping biologists better understand the workings of the electron transport chain.Methods
We propose a method based on Position Specific Scoring Matrix (PSSM) profiles and significant amino acid pairs to identify metal-binding residues in electron transport proteins.Results
We have selected a non-redundant set of 55 metal-binding electron transport proteins as our dataset. The proposed method can predict metal-binding sites in electron transport proteins with an average 10-fold cross-validation accuracy of 93.2% and 93.1% for metal-binding cysteine and histidine, respectively. Compared with the general metal-binding predictor from A. Passerini et al., the proposed method can improve over 9% of sensitivity, and 14% specificity on the independent dataset in identifying metal-binding cysteines. The proposed method can also improve almost 76% sensitivity with same specificity in metal-binding histidine, and MCC is also improved from 0.28 to 0.88.Conclusions
We have developed a novel approach based on PSSM profiles and significant amino acid pairs for identifying metal-binding sites from electron transport proteins. The proposed approach achieved a significant improvement with independent test set of metal-binding electron transport proteins. 相似文献1000.