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排序方式: 共有114条查询结果,搜索用时 15 毫秒
31.
Demographic information and laboratory test results on 136 169 clinical serum specimens submitted to the public health laboratory in Manitoba, Canada, for hepatitis C virus (HCV) testing between January 1995 and December 2003 were analyzed. The difference in the clearance rates of HCV infection, without therapeutic intervention, and the HCV genotypes infecting First Nation and non-First Nation people were studied. The rates of co-infection of HCV-positive individuals with other hepatitis viruses were also compared between the two study groups. The results of the analyses of the data indicated that there was a 4.4-fold increase in the number of specimens tested and a 4.9-fold decrease in HCV antibody (anti-HCV) positive cases during the study period. The proportion of specimens submitted for testing from First Nation individuals was lower than their proportion in the Manitoba population. Our study also indicated that there was a significantly higher proportion of First Nation patients who had self-limiting infection (patients cleared the infection and became HCV RNA negative without anti-HCV treatment) in comparison to non-First Nation patients. The proportion of First Nation females who had self-limiting infection was significantly higher than non-First Nation females. HCV genotype 1 infection represented more than 60% of HCV infection in Manitoba. The rate of individuals positive for the hepatitis A virus antibody in the HCV-positive population was higher among First Nation than non-First Nation individuals. On the other hand, there were more HCV-infected First Nation patients than non-First Nation patients who were not immune to the hepatitis B virus. The data indicate that fewer First Nation patients seek anti-HCV therapy in comparison to non-First Nation. In conclusion, the differences in the rates of HCV self-limiting infection between First Nation and non-First Nation individuals in Manitoba may reflect the genetic differences between the two cohorts, which may consequently affect the immune response to the HCV infection. 相似文献
32.
Salaheddin M. Mahmud Marissa Becker Yoav Keynan Lawrence Elliott Laura H. Thompson Keith Fowke Lisa Avery Paul Van Caeseele Sande Harlos James Blanchard Magdy Dawood 《CMAJ》2010,182(14):1522-1524
Background
Hospitalization and lab confirmed cases of H1N1 have been reported during the first wave of the 2009 pandemic but these are not accurate measures of influenza incidence in the population. We estimated the cumulative incidence of pandemic (H1N1) influenza among pregnant women in the province of Manitoba during the first wave of the 2009 pandemic.Methods
Two panels of stored frozen serum specimens collected for routine prenatal screening were randomly selected for testing before (March 2009, n = 252) and after (August 2009, n = 296) the first wave of the pandemic. A standard hemagglutination inhibition assay was used to detect the presence of IgG antibodies against the pandemic (H1N1) 2009 virus. The cumulative incidence of pandemic (H1N1) influenza was calculated as the difference between the point prevalence rates in the first and second panels.Results
Of the specimens collected in March, 7.1% were positive for the IgG antibodies (serum antibody titre ≥ 1:40). The corresponding prevalence was 15.7% among the specimens collected in August. The difference indicated a cumulative incidence of 8.6% (95% confidence interval [CI] 3.2%–13.7%). The rate differed geographically, the highest being in the northern regions (20.8%, 95% CI 7.9%–31.8%), as compared with 4.0% (95% CI 0.0%–11.9%) in Winnipeg and 8.9% (95% CI 0.0%–18.8%) in the rest of the province.Interpretation
We estimated that the cumulative incidence of pandemic (H1N1) influenza among pregnant women in Manitoba during the first wave of the 2009 pandemic was 8.6%. It was 20.8% in the northern regions of the province.During the first wave of the pandemic (H1N1) 2009, the province of Manitoba was more severely affected than almost any other Canadian province.1 Pregnant women in particular had higher rates of laboratory-confirmed infection and of severe illness.2 However, the number of laboratory-confirmed cases is not an accurate measure of the incidence of influenza in the population. The number and geographic distribution of confirmed cases are influenced by differences in access to medical care, physicians’ practices and other factors.3We estimated the cumulative incidence of pandemic (H1N1) influenza among pregnant women in the province of Manitoba during the first wave of the 2009 pandemic. We did this by measuring the point seroprevalence in random samples of pregnant women presenting for routine prenatal screening before and after the first wave. 相似文献33.
Mohammad Iqbal Muhammad Dawood Shah Chau Ann Lie Chin Kim San 《Molecular and cellular biochemistry》2010,341(1-2):271-277
This study was aimed to evaluate the effect of Strobilanthes crispus extract for possible protection against lipid peroxidation and DNA damage induced by iron nitrilotriacetate (Fe-NTA) and hydrogen peroxide (H2O2). Fe-NTA is a potent nephrotoxic agent and induces acute and subacute renal proximal tubular necrosis by catalyzing the decomposition of H2O2-derived production of hydroxyl radicals, which are known to cause lipid peroxidation and DNA damage. Incubation of postmitochondrial supernatant and/or calf thymus DNA with H2O2 (40 mM) in the presence of Fe-NTA (0.1 mM) induces lipid peroxidation and DNA damage to about 2.3-fold and 2.9-fold, respectively, as compared to control (P < 0.05). In lipid peroxidation protection studies, S. crispus treatment showed a dose-dependent inhibition (45–53% inhibition, P < 0.05) of Fe-NTA and H2O2 induced lipid peroxidation. Similarly, in DNA damage protection studies, S. crispus treatment also showed a dose-dependent inhibition (18–30% inhibition, P < 0.05) of DNA damage. In addition, the protection was closely related to the content of phenolic compounds as evident by S. crispus extract showing the value of 124.48 mg/g total phenolics expressed as gallic acid equivalent (GAE, mg/g of extract). From these studies, it is concluded that S. crispus inhibits peroxidation of membrane lipids and DNA damage induced by Fe-NTA and H2O2 and possesses the potential to be used to treat or prevent degenerative diseases where oxidative stress is implicated. 相似文献
34.
Sharov AA Piao Y Matoba R Dudekula DB Qian Y VanBuren V Falco G Martin PR Stagg CA Bassey UC Wang Y Carter MG Hamatani T Aiba K Akutsu H Sharova L Tanaka TS Kimber WL Yoshikawa T Jaradat SA Pantano S Nagaraja R Boheler KR Taub D Hodes RJ Longo DL Schlessinger D Keller J Klotz E Kelsoe G Umezawa A Vescovi AL Rossant J Kunath T Hogan BL Curci A D'Urso M Kelso J Hide W Ko MS 《PLoS biology》2003,1(3):E74
35.
The tyrosine kinase p56lck is essential in coxsackievirus B3-mediated heart disease 总被引:11,自引:0,他引:11
Liu P Aitken K Kong YY Opavsky MA Martino T Dawood F Wen WH Kozieradzki I Bachmaier K Straus D Mak TW Penninger JM 《Nature medicine》2000,6(4):429-434
Infections are thought to be important in the pathogenesis of many heart diseases. Coxsackievirus B3 (CVB3) has been linked to chronic dilated cardiomyopathy, a common cause of progressive heart disease, heart failure and sudden death. We show here that the sarcoma (Src) family kinase Lck (p56lck) is required for efficient CVB3 replication in T-cell lines and for viral replication and persistence in vivo. Whereas infection of wild-type mice with human pathogenic CVB3 caused acute and very severe myocarditis, meningitis, hepatitis, pancreatitis and dilated cardiomyopathy, mice lacking the p56lck gene were completely protected from CVB3-induced acute pathogenicity and chronic heart disease. These data identify a previously unknown function of Src family kinases and indicate that p56lck is the essential host factor that controls the replication and pathogenicity of CVB3. 相似文献
36.
Eric Budgell Adam L. Cohen Jo McAnerney Sibongile Walaza Shabir A. Madhi Lucille Blumberg Halima Dawood Kathleen Kahn Stefano Tempia Marietjie Venter Cheryl Cohen 《PloS one》2015,10(3)
Background
The World Health Organisation recommends outpatient influenza-like illness (ILI) and inpatient severe acute respiratory illness (SARI) surveillance. We evaluated two influenza surveillance systems in South Africa: one for ILI and another for SARI.Methodology
The Viral Watch (VW) programme has collected virological influenza surveillance data voluntarily from patients with ILI since 1984 in private and public clinics in all 9 South African provinces. The SARI surveillance programme has collected epidemiological and virological influenza surveillance data since 2009 in public hospitals in 4 provinces by dedicated personnel. We compared nine surveillance system attributes from 2009–2012.Results
We analysed data from 18,293 SARI patients and 9,104 ILI patients. The annual proportion of samples testing positive for influenza was higher for VW (mean 41%) than SARI (mean 8%) and generally exceeded the seasonal threshold from May to September (VW: weeks 21–40; SARI: weeks 23–39). Data quality was a major strength of SARI (most data completion measures >90%; adherence to definitions: 88–89%) and a relative weakness of the VW programme (62% of forms complete, with limited epidemiologic data collected; adherence to definitions: 65–82%). Timeliness was a relative strength of both systems (e.g. both collected >93% of all respiratory specimens within 7 days of symptom onset). ILI surveillance was more nationally representative, financially sustainable and expandable than the SARI system. Though the SARI programme is not nationally representative, the high quality and detail of SARI data collection sheds light on the local burden and epidemiology of severe influenza-associated disease.Conclusions
To best monitor influenza in South Africa, we propose that both ILI and SARI should be under surveillance. Improving ILI surveillance will require better quality and more systematic data collection, and SARI surveillance should be expanded to be more nationally representative, even if this requires scaling back on information gathered. 相似文献37.
Differential T cell trafficking through the blood compartment towards infected foci may be occurring in different stages of tuberculosis disease and infection. The aim of the present study was to identify cytokine signatures in the blood compartment in tuberculosis patients with pulmonary disease (PTB=19), recently exposed household contacts (HC=27) and nonexposed community controls (EC=37). Diluted (1:10) whole blood was cultured for 2 days and cytokine secretion was assessed using Cytometric Bead Array (Th1/Th2 kit II; BD Biosciences) which included IL-2, TNF-α, IFN-γ (Type1/T1), IL-4, IL-6 and IL-10 (Type2/T2). All T1/T2 cytokines were elevated in PTB (AUROC>0.9) while HC showed selective elevation of IL-6 (AUROC>0.7) compared to EC. Principal component analysis (PCA) extracted two groupings with Eigen values >1; IL-6 separated into the second component for PTB, HC and EC. After rotation, IFN-γ was correlated with the first component for PTB and EC and the second component for HC indicating an absence of T1/T2 dichotomy. Therefore endogenous cytokine signatures may indicate differential T cell trafficking in different stages of tuberculosis infection and disease. 相似文献
38.
39.
A.E. Ismail Mona G. Dawood Wafaa M.A. El-Nagdi 《Archives Of Phytopathology And Plant Protection》2013,46(18):2155-2164
The effects of four waste residues from castor (Ricinus communis L.), rocket (Eruca sativa Mill.), linseed (Linum usitatissimum L.) and wheat germ (Triticum aestivum L.) crops oil extraction as soil amendments at three rates (on base lower rate, recommended rate and higher rate), in comparison with the nematicide Nemacur 10% G were evaluated in greenhouse conditions (25 ± 5°C) at the National Research Center, Egypt, during two successive seasons on the physiological influence on the eggplant and on the infection by the root-knot nematode Meloidogyne incognita. All the tested treatments significantly reduced the numbers of juveniles in soil or in roots, number of galls, egg-masses, gall and egg-mass indices and the rate of nematode build-up. Significant differences in the nematode stages were found within and between treatments. The percentage reduction in the nematode stages was greater with the use of wheat germ mill residues (WGMR) compound followed by castor seed mill residues (CAMR) compound, rocket seed mill residues (RSMR) and Nemacur 10% G. The application of linseed mill residues (LSMR) was the least effective in reducing the nematode stages. Regarding infected plants, all the evaluated amendments achieved significant increases in the almost shoot and root growth variables, total contents of photosynthetic pigments, phenolics and carbohydrates when compared with nematode inoculated and untreated plants. As for healthy plants, it is clear that all the doses of WGMR compound and the highest doses (3.75%, w/w) of the other additives had pronounced effect on the growth parameters and phenolic content of dry leaves of the eggplant. In addition, all the treatments increased photosynthetic pigments and carbohydrates content of the eggplant. These results indicate that some seed mill residues may be used as natural nematicides in controlling M. incognita nematode and improving the growth and some chemical composition of the eggplant. 相似文献
40.
Edmund Carl February Nicky Allsopp Tirello Shabane Dawood Hattas 《Plant and Soil》2011,349(1-2):253-260
Here we aim to demonstrate that in arid environments the competitive balance between species can be determined by niche separation with either nitrogen or water as the relevant niche axis. To do this we sampled roots <2 mm in diameter for 5 soil pits equidistant between two coexisting species, a shrub and a grass. Using stable carbon and nitrogen isotope ratios of fine roots we determine both photosynthetic pathway and rooting depth. We also examine the distribution of soil moisture and nitrogen relative to root biomass. Our results for root biomass and stable isotope ratios of fine roots demonstrate both niche separation and competition for resources. Root biomass is highest at the top of the profile where soil nitrogen is highest and soil moisture is lowest. We conclude that while there is competition for resources in the middle of the profile, competition is mitigated by photosynthetic pathway. The facultative CAM shrub grows whenever the soil at the surface is wet enough. The C4 photosynthetic pathway of the grass is more nitrogen and water use efficient making it better adapted to the low nitrogen in the middle of the profile and low summer rainfall. 相似文献