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51.
Risk factors for incident HIV infection among anonymous HIV testing site clients in Santos,Brazil: 1996-1999 总被引:1,自引:0,他引:1
Alves K Shafer KP Caseiro M Rutherford G Falcao ME Sucupira MC Busch MP Rawal BD Diaz RS 《Journal of acquired immune deficiency syndromes (1999)》2003,32(5):551-559
OBJECTIVES: To determine temporal trends in HIV infection and risk factors among persons seeking anonymous HIV testing in Santos, Brazil. METHODS: Data and sera from persons testing for HIV from 1996 to 1999 were used. Exposures were abstracted from HIV testing risk assessments. Stored HIV-positive sera were tested to identify recently acquired HIV infection using a serologic testing algorithm for detecting recent HIV seroconversion (STARHS). Independent associations between exposures and recently acquired HIV infection were determined using multivariate analyses. RESULTS: Overall, estimated HIV incidence was 2.0% (95% CI: 1.1-3.5) for the 4-year period: 1.2% (95% CI: 0.5-2.6) in women and 2.7% (95% CI: 1.3-5.0) in men. Incidence increased among women but remained stable among men. Exposures independently associated with incident infection included a history of sex work (OR= 5.4, 95% CI: 1.5-18.7), concurrent syphilis infection (OR =4.1, 95% CI: 1.4-11.9), anal sex (OR = 3.0, 95% CI: 1.3-7.1), and having an HIV-positive sexual partner (OR= 1.4, 95% CI: 1.1-1.9). CONCLUSIONS: This study further demonstrates the public health utility of using the STARHS for the assessment of emerging trends in the HIV epidemic. Results from this study will help to target appropriate prevention strategies directed toward at-risk populations in Santos. 相似文献
52.
Bladder acellular matrix as a substrate for studying in vitro bladder smooth muscle-urothelial cell interactions 总被引:17,自引:0,他引:17
Brown AL Brook-Allred TT Waddell JE White J Werkmeister JA Ramshaw JA Bagli DJ Woodhouse KA 《Biomaterials》2005,26(5):529-543
The objective of this study was to evaluate the ability of bladder acellular matrix (BAM) to support the individual and combined growth of primary porcine bladder smooth muscle (SMC) and urothelial (UEC) cells. An in vitro co-culture system was devised to evaluate the effect of UEC on (i) SMC-mediated contraction of BAM discs, and (ii) SMC invasiveness into BAM. Cells were seeded onto BAM discs under 4 different culture conditions. Constructs were incubated for 1, 7, 14 and 28 days. Samples were then harvested for evaluation of matrix contraction. Immunohistochemistry (IHC) was utilized to examine cellular organization within the samples and conditioned media supernatants analyzed for net gelatinase activity. BAM contraction was significantly increased with co-culture. The same side co-culture configuration lead to a greater reduction in surface area than opposite side co-culture. IHC revealed enhanced SMC infiltration into BAM when co-culture was utilized. A significant increase in net gelatinase activity was also observed with the co-culture configuration. Enhanced infiltration and contractile ability of bladder SMCs with UEC co-culture may, in part, be due to an increase in gelatinase activity. The influence of bladder UECs on SMC behaviour in vitro indicates that BAM may contain some key inductive factors that serve to promote important bladder cell-cell and cell-matrix interactions. 相似文献
53.
Kimberly Mascia Larry Borish James Patrie John Hunt C Douglas Phillips John W Steinke 《Annals of allergy, asthma & immunology》2005,94(6):652-657
BACKGROUND: Aspirin-exacerbated respiratory disease (AERD) is a disease of intense eosinophilic inflammation that can produce fibrosis, hyperplasia, and remodeling. OBJECTIVE: To investigate the usefulness of quantifying severity of chronic hyperplastic eosinophilic sinusitis in predicting the presence of AERD. METHODS: Data were compared between asthmatic patients who reported exacerbations after aspirin ingestion and those who did not. The primary outcome measure was severity of sinusitis using a validated computed tomography (CT) scan-based scoring system. Indices of lower airway remodeling and other markers of inflammation were also evaluated. RESULTS: Twenty-one patients with AERD were compared with 19 patients with aspirin-tolerant asthma (ATA). Patients were well matched for asthma severity as shown by their similar lung function as measured by postbronchodilator forced expiratory volume in 1 second. Patients with AERD were distinguished by their sinus CT scores (AERD patients: 16.9; 95% confidence interval [CI], 13.4-21.3; ATA patients: 6.2; 95% CI, 4.2-9.1; P < .001), and they were considerably more likely to have nasal polyps (AERD patients: 90%; ATA patients: 26%; P < .001). In addition, AERD patients demonstrated increased total lung capacity (AERD patients: 107.9%; 95% CI, 99.9%-117.6%; ATA patients: 98.0%; 95% CI, 93.7%-102.5%; P = .05), reflecting a trend toward increased air trapping. No significant differences occurred in diffusing capacity, exhaled nitric oxide, eosinophilia, or exhaled breath condensate pH. CONCLUSIONS: AERD can be distinguished from ATA by the extent of hyperplasia on CT scan and the presence of nasal polyps. We hypothesize that AERD represents a remodeling process that affects both the upper and lower airways. 相似文献
54.
Factor structure and validity of the parenting scale. 总被引:1,自引:0,他引:1
Kimberly A Rhoades Susan G O'Leary 《Journal of clinical child and adolescent psychology》2007,36(2):137-146
Confirmatory factor analyses based on the scoring derived from 5 prior studies of the Parenting Scale were conducted using a representatively recruited sample of 453 couples parenting 3-to 7-year-old children. Comparative analyses favored the Reitman et al. (2001) 2-factor scoring system as well as a 3-factor solution, including Lax, Overreactive, and Hostile discipline. This 3-factor solution demonstrated good fit across parent gender and child age and gender. Mothers rated themselves as more overreactive than fathers. The factor scores correlated significantly with several validity measures, including child behavior problems. The Hostile factor contributed significantly to the prediction of child behavior problems after controlling for Lax and Overreactive discipline. Both parents reported using more dysfunctional discipline than they thought they should. 相似文献
55.
There continues to be no consensus definition of executive functions. One way to understand different executive function components is to study abilities at their emergence, that is, early in development, and use advanced statistical methods to understand the interrelations among executive processes. However, to fully determine the constructs of interest, these methods often require complete data on a large battery of tasks, which are difficult to obtain with young children. Path analysis is an alternative statistical technique that requires only a single measure of each construct, yet still allows researchers to investigate complex relations among measures, to compare nested models, and to compare model fit across groups. Therefore, 117 preschool children (ages 2 years 8 months to 6 years 0 months) completed several executive function tasks. Path analysis was used to determine the relations between complex problem solving and working memory, inhibition, and set shifting processes. The best-fitting model included paths from working memory and inhibition to problem solving, and a correlation between working memory and inhibition. Interestingly, in younger children, inhibition was the strongest predictor of problem solving, whereas working memory contributed more strongly in older children. Suggestions for useful statistical methods to investigate the relations among executive functions in children are discussed. 相似文献
56.
Recombinant Helicobacter bilis Protein P167 for Mouse Serodiagnosis in a Multiplex Microbead Assay
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Sunlian Feng Lon V. Kendall Emir Hodzic Scott Wong Edward Lorenzana Kimberly Freet Karin S. Ku Paul A. Luciw Stephen W. Barthold Imran H. Khan 《Clinical and Vaccine Immunology : CVI》2004,11(6):1094-1099
Infection of mice with Helicobacter bilis is widespread in research and commercial mouse colonies. Therefore, sensitive, specific, and high-throughput assays are needed for rapid and accurate testing of mice in large numbers. This report describes a novel multiplex assay, based on fluorescent microbeads, for serodetection of H. bilis infection. The assay requires only a few microliters of serum to perform and is amenable to a high-throughput format. Individual microbead sets were conjugated to purified, H. bilis-specific, recombinant proteins P167C and P167D and bacterial membrane extracts from H. bilis and Helicobacter hepaticus. For detecting H. bilis infection in the microbead multiplex assay, P167C and P167D provided significantly higher sensitivities (94 and 100%, respectively) and specificities (100 and 95%, respectively) than membrane extract (78% sensitivity and 65% specificity). Microbead multiplex assay results were validated by enzyme-linked immunosorbent assay. Purified recombinant proteins showed low batch-to-batch variation; this feature allows for ease of quality control, assay robustness, and affordability. Thus, recombinant antigens are highly suitable in the multiplex microbead assay format for serodetection of H. bilis infection. 相似文献
57.
Malone FD Canick JA Ball RH Nyberg DA Comstock CH Bukowski R Berkowitz RL Gross SJ Dugoff L Craigo SD Timor-Tritsch IE Carr SR Wolfe HM Dukes K Bianchi DW Rudnicka AR Hackshaw AK Lambert-Messerlian G Wald NJ D'Alton ME;First- Second-Trimester Evaluation of Risk 《The New England journal of medicine》2005,353(19):2001-2011
58.
59.
Bidwell J Keen L Gallagher G Kimberly R Huizinga T McDermott MF Oksenberg J McNicholl J Pociot F Hardt C D'Alfonso S 《Genes and immunity》1999,1(1):3-19
The pathologies of many infectious, autoimmune and malignant diseases are influenced by the profiles of cytokine production in pro-inflammatory (TH1) and anti-inflammatory (TH2) T cells. Interindividual differences in cytokine profiles appear to be due, at least in part, to allelic polymorphism within regulatory regions of cytokine gene. Many studies have examined the relationship between cytokine gene polymorphism, cytokine gene expression in vitro, and the susceptibility to and clinical severity of diseases. A review of the findings of these studies is presented. An on-line version featuring appropriate updates is accessible from the World Wide Web site, http://www.pam.bris.ac.uk/services/GAI/cytokine4.htm. 相似文献
60.
Neurons isolated from the lateral vestibular nucleus of young adult and senescent Fischer-344 rats were incubated with fluorescamine-labelled Concanavalin A (fl-Con A) alone, or following incubation in trypsin or Vibrio cholerae neuraminidase. They were then observed and photographed. Microdensitometric analysis of fluorescence micrographs showed that senescent rat neurons were significantly more fluorescent than those from young adult rats. Additionally, either patches or caps of fl-Con A were seen on the surface of neurons from senescent rats, while most young adult rat neurons bound fl-Con A uniformly. Pretreatment with trypsin or neuraminidase had no effect on the amount of fluorescence on the surface of senescent rat neurons, and only a slight effect on the surface distribution. Trypsin and neuraminidase treatments caused a significant increase in fluorescence on the neuronal plasma membranes of young adult rats and a rearrangement of the binding pattern in the majority of neurons observed. 相似文献