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81.
Ngo T Hoa Tran TB Chieu Ho DT Nghia Nguyen TH Mai Pham H Anh Marcel Wolbers Stephen Baker James I Campbell Nguyen VV Chau Tran T Hien Jeremy Farrar Constance Schultsz 《BMC infectious diseases》2011,11(1):1-8
Background
Our objective was to determine the frequency and determinants of presentation to care with advanced HIV disease in patients who discover their HIV diagnosis at this stage as well as those with delayed presentation to care after HIV diagnosis in earlier stages.Methods
We collected data on 1,819 HIV-infected patients in Brussels (Belgium) and Northern France from January 1997 to December 2007. "Advanced HIV disease" was defined as CD4 count <200/mm3 or clinically-defined AIDS at study inclusion and was stratified into two groups: (a) late testing, defined as presentation to care with advanced HIV disease and HIV diagnosis ≤6 months before initiation of HIV care; and (b) delayed presentation to care, defined as presentation to care with advanced HIV disease and HIV diagnosis >6 months before initiation of HIV care. We used multinomial logistic regression to determine the factors associated with delayed presentation to care and late testing.Results
Of the 570 patients initiating care with advanced HIV disease, 475 (83.3%) were tested late and 95 (16.7%) had delayed presentation to care. Risk factors for delayed presentation to care were: age 30-50 years, injection drug use, and follow-up in Brussels. Risk factors for late testing were: sub-Saharan African origin, male gender, and older age. HIV transmission through heterosexual contact was associated with an increased risk of both delayed presentation to care and late testing. Patients who initiated HIV care in 2003-2007 were less likely to have been tested late or to have a delayed presentation to care than patients who initiated care before 2003.Conclusion
A considerable proportion of HIV-infected patients present to care with advanced HIV disease. Late testing, rather than a delay in initiating care after earlier HIV testing, is the main determinant of presentation to care with advanced HIV disease. The factors associated with delay presentation to care differ from those associated with late testing. Different strategies should be developed to optimize early access to care in these two groups. 相似文献82.
83.
Polycyclic aromatic hydrocarbon-DNA adducts in human placenta and modulation by CYP1A1 induction and genotype 总被引:6,自引:1,他引:5
Whyatt RM; Bell DA; Jedrychowski W; Santella RM; Garte SJ; Cosma G; Manchester DK; Young TL; Cooper TB; Ottman R; Perera FP 《Carcinogenesis》1998,19(8):1389-1392
This study investigated the relationship in human placenta between
polycyclic aromatic hydrocabon (PAH)-DNA adduct levels and two biomarkers
of cytochrome P4501A1 (CYP1A1): gene induction evidenced by CYP1A1 mRNA,
and a genetic polymorphism, the CYP1A1 MspI RFLP. CYP1A1 codes for an
inducible enzyme system that catalyzes the bioactivation of PAHs. Prior
research found a high correlation in human lung tissue between CYP1A1
activity and DNA damage from PAHs. The CYP1A1 Mspi RFLP has been linked in
some studies to risk of lung cancer. The relationships in human placenta
between DNA damage, CYP1A1 activity and genotype have not been well
characterized and may be relevant to risks from transplacental PAH
exposure. The study cohort consisted of 70 newborns from Krakow, Poland, a
city with elevated air pollution, and 90 newborns from nearby Limanowa, an
area with lower air pollution but greater indoor coal use. Contrary to
results seen previously in lung tissue, CYP1A1 mRNA was not significantly
correlated with PAH-DNA adduct levels in the placenta. Smoking
(self-reported maternal and infant plasma cotinine) was significantly
associated with CYP1A1 mRNA levels (P < 0.01), but not with PAH-DNA
adduct levels. Placental PAH- DNA adduct levels were significantly higher
in infants with the CYP1A1 MspI restriction site compared with infants
without the restriction site (P < 0.01), implicating a genetic factor in
inter-individual variation in DNA damage in human placenta. Further studies
are needed to determine the relevance of this finding to risk of
transplacental carcinogenesis.
相似文献
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86.
河南省肺结核流行趋势及病例发现方法分析 总被引:11,自引:0,他引:11
目的 以河南省第四次全国结核病流行病学抽样调查(流调)数据为依据,揭示河南省结核病疫情现状及变化趋势,并就病例发现方法进行分析。方法 应用痰检和X线、PPD等检查手段,从46个流调点的抽样人群中筛选活动性肺结核患。结果 活动性肺结核患病率497/10万,涂阳肺结核患病率132/10万,菌阳肺结核患病率为159/10万。与1990年流调结果相比,10年间涂阳患病率下降6.15%,年平均递降率仅为0.63%,下降极为缓慢。增加1次痰涂片检查,可提高6.6%的病例发现率。结论 河南省结核病疫情仍很严重,病例发现工作有待加强,加强肺结核可疑症状查痰有助于提高传染性肺结核患的发现率。 相似文献
87.
Kirchhofer D; Sakariassen KS; Clozel M; Tschopp TB; Hadvary P; Nemerson Y; Baumgartner HR 《Blood》1993,81(8):2050-2058
Endothelial cell-mediated coagulation and leukocyte adhesion are processes that might be connected by the generation of thrombin. To examine the interaction of procoagulant and proadhesive activity, cultures of endothelial cells were stimulated with tumor necrosis factor-alpha, which resulted in the surface expression of tissue factor. Subsequent exposure to human nonanticoagulated blood at a shear rate of 100 s-1 in a parallel plate perfusion device led to the deposition of polymerized fibrin, which covered 63% of the endothelial surface. In addition, numerous platelet aggregates (71 per 10 mm cross- section) and leukocytes (53 +/- 6/mm2) were deposited on stimulated endothelial cells, whereas no fibrin and only a few platelet aggregates (4 +/- 1 per 10 mm cross-section) and leukocytes (6 +/- 1/mm2) were detected on control cells. A significant portion of the adherent leukocytes bound to fibrin and platelets. However, when the deposition of fibrin and platelet aggregates was inhibited with the anti-tissue factor antibody HTFI-7B8 by 100% and 86%, respectively, leukocyte adherence remained unchanged (68 +/- 6/mm2). This indicated that leukocytes could efficiently adhere to endothelial cells through direct cell-cell contact independent of both thrombin and deposited fibrin. Moreover, this direct adhesion of leukocytes to the endothelial surface was reduced twofold to threefold when fibrin deposition occurred. These data suggest a relationship between endothelial procoagulant and proadhesive properties in that tissue factor-initiated coagulation may contribute to leukocyte adhesion through the formation of an adhesive fibrin/platelet meshwork but concurrently prevents the adhesive endothelial surface to bind leukocytes at its full capacity. 相似文献
88.
P. de Colombani A. Hovhannesyan Wolfheze Working Group on Social Determinants of TB Drug Resistant TB 《Public Health Action》2015,5(3):194-201
Setting: National tuberculosis programmes (NTPs) of the 53 Member States of the World Health Organization (WHO) European Region.Objectives: To identify the social determinants and underlying risk factors for tuberculosis (TB) as routinely monitored by NTPs and to identify those feasible and appropriate to be included in the annual reporting to the joint European Centre for Disease Prevention and Control (ECDC) WHO reporting platform.Design: A semi-structured questionnaire sent to 53 national TB surveillance correspondents.Results: A total of 47 countries submitted questionnaires; most of the countries collect a number of social determinants and risk factors that are not requested for reporting to the Joint ECDC-WHO Reporting Platform. Occupation/employment, homelessness, diabetes mellitus and use of alcohol are collected by the majority of countries, but without standardised definitions.Conclusions: Four social determinants/risk factors are already included in the national TB surveillance systems of the majority of countries and could be incorporated in the annual reporting to the Joint ECDC/WHO Reporting Platform. Standardised epidemiological case definitions need to be adopted. 相似文献
89.
MA Eluwa II Inyangmme AO Akpantah TB Ekanem MB Ekong OR Asuquo AA Nwakanma 《African health sciences》2013,13(3):541-545
Background
Carbonated drinks are widely consumed because of their taste and their ability to refresh and quench thirst. These carbonated drinks also exist in the form of diet drinks, for example Diet Coke®, Pepsi®, extra.Objectives
A comparative effect of the diet and regular soda carbonated drinks on the histology of the cerebellum of female albino Wistar rats was investigated.Methods
Fifteen adult female Wistar rats weighing between 180–200g were divided into 3 groups; designated as groups A, B and C, and each group consisted of five rats. Group A was the Control group and received distilled water, while groups B and C were the experimental groups. Group B was administered 50 ml of regular soda (RS), and group C was administered 50 ml of diet soda (DS) each per day for 21 days, and the rats were sacrificed on Day 22, and their cerebellums excised and preserved.Results
Histological result of the sections of the cerebellum showed shrunken and degenerated Purkinje cells with hypertrophied dendrites, especially in the DS group, which was less in the RS group compared to the control group.Conclusion
These results suggest that diet soda has adverse effect on the cerebellum of adult female albino Wistar rats. 相似文献90.
Division of Viral Hepatitis National Center for HIV/AIDS Viral Hepatitis STD TB Prevention 《MMWR Recomm Rep》2012,61(RR-4):1-32
Hepatitis C virus (HCV) is an increasing cause of morbidity and mortality in the United States. Many of the 2.7-3.9 million persons living with HCV infection are unaware they are infected and do not receive care (e.g., education, counseling, and medical monitoring) and treatment. CDC estimates that although persons born during 1945-1965 comprise an estimated 27% of the population, they account for approximately three fourths of all HCV infections in the United States, 73% of HCV-associated mortality, and are at greatest risk for hepatocellular carcinoma and other HCV-related liver disease. With the advent of new therapies that can halt disease progression and provide a virologic cure (i.e., sustained viral clearance following completion of treatment) in most persons, targeted testing and linkage to care for infected persons in this birth cohort is expected to reduce HCV-related morbidity and mortality. CDC is augmenting previous recommendations for HCV testing (CDC. Recommendations for prevention and control of hepatitis C virus (HCV) infection and HCV-related chronic disease. MMWR 1998;47[No. RR-19]) to recommend one-time testing without prior ascertainment of HCV risk for persons born during 1945-1965, a population with a disproportionately high prevalence of HCV infection and related disease. Persons identified as having HCV infection should receive a brief screening for alcohol use and intervention as clinically indicated, followed by referral to appropriate care for HCV infection and related conditions. These recommendations do not replace previous guidelines for HCV testing that are based on known risk factors and clinical indications. Rather, they define an additional target population for testing: persons born during 1945-1965. CDC developed these recommendations with the assistance of a work group representing diverse expertise and perspectives. The recommendations are informed by the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) framework, an approach that provides guidance and tools to define the research questions, conduct the systematic review, assess the overall quality of the evidence, and determine strength of the recommendations. This report is intended to serve as a resource for health-care professionals, public health officials, and organizations involved in the development, implementation, and evaluation of prevention and clinical services. These recommendations will be reviewed every 5 years and updated to include advances in the published evidence. 相似文献