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171.
Martin S Herder C Schloot NC Koenig W Heise T Heinemann L Kolb H;DIATOR Study Group 《PloS one》2011,6(3):e17554
Background
Recent evidence suggests that the lipid-lowering agent atorvastatin is also a potent immunomodulator. The aim of this study was to investigate the possible effect of atorvastatin on the decline of residual beta cell function in recent-onset type 1 diabetes.Methods and Findings
The randomised placebo-controlled Diabetes and Atorvastatin (DIATOR) Trial included 89 patients with newly diagnosed type 1 diabetes and islet autoantibodies (mean age 30 years, 40% females), in 12 centres in Germany. Patients received placebo or 80 mg/d atorvastatin for 18 months. As primary outcome stimulated serum C-peptide levels were determined 90 min after a standardized liquid mixed meal. An intent-to-treat analysis was performed. Fasting and stimulated C-peptide levels were not significantly different between groups at 18 months. However, median fasting serum C-peptide levels dropped from baseline to 12 and 18 months in the placebo group (from 0. 34 to 0.23 and 0.20 nmol/l, p<0.001) versus a nonsignificant decline in the atorvastatin group (from 0.34 to 0.27 and 0.30 nmol/l, ns). Median stimulated C-peptide concentrations declined between baseline and 12 months (placebo from 0.89 to 0.71 nmol/l, atorvastatin from 0.88 to 0.73 nmol/l, p<0.01 each) followed by a major loss by month 18 in the placebo group (to 0.48 nmol/l, p = 0.047) but not in the atorvastatin group (to 0.71 nmol/l, ns). Median levels of total cholesterol and C-reactive protein decreased in the atorvastatin group only (p<0.001 and p = 0.04). Metabolic control was similar between groups.Conclusions
Atorvastatin treatment did not significantly preserve beta cell function although there may have been a slower decline of beta-cell function which merits further study.Trial Registration
ClinicalTrials.gov NCT00974740相似文献172.
Kaiser R Bunnell R Hightower A Kim AA Cherutich P Mwangi M Oluoch T Dadabhai S Mureithi P Mugo N Mermin J;KAIS Study Group 《PloS one》2011,6(3):e17842
Background
In order to inform prevention programming, we analyzed HIV discordance and concordance within couples in the Kenya AIDS Indicator Survey (KAIS) 2007.Methods
KAIS was a nationally representative population-based sero-survey that examined demographic and behavioral indicators and serologic testing for HIV, HSV-2, syphilis, and CD4 cell counts in 15,853 consenting adults aged 15–64 years. We analyzed interview and blood testing data at the sexual partnership level from married or cohabitating couples. Multivariable regression models were used to identify factors independently associated with HIV discordant and concordant status.Results
Of 3256 couples identified in the survey, 2748 (84.4%) had interview and blood testing data. Overall, 3.8% of couples were concordantly infected with HIV, and in 5.8% one partner was infected, translating to 338,000 discordant couples in Kenya. In 83.6% of HIV-infected Kenyans living in married or cohabitating couples neither partner knew their HIV status. Factors independently associated with HIV-discordance included young age in women (AOR 1.5, 95% CI: 1.2–1.8; p<0.0001), increasing number of lifetime sexual partners in women (AOR 1.5, 95% CI: 1.3–1.8; p<0.0001), HSV-2 infection in either or both partners (AOR 4.1, 95% CI: 2.3–7.2; p<0.0001), and lack of male circumcision (AOR 1.6, 95% CI: 1.0–2.5; p = 0.032). Independent factors for HIV-concordance included HSV-2 infection in both partners (AOR 6.5, 95% CI: 2.3–18.7; p = 0.001) and lack of male circumcision (AOR 1.8, 95% CI: 1.0–3.3; p = 0.043).Conclusions
Couple prevention interventions should begin early in relationships and include mutual knowledge of HIV status, reduction of outside sexual partners, and promotion of male circumcision among HIV-uninfected men. Mechanisms for effective prevention or suppression of HSV-2 infection are also needed. 相似文献173.
Cooper C Thorne A Klein M Conway B Boivin G Haase D Shafran S Zubyk W Singer J Halperin S Walmsley S;CIHR Canadian HIV Trials Network Influenza Vaccine Research Group 《PloS one》2011,6(3):e17758
Introduction
The risk of poor vaccine immunogenicity and more severe influenza disease in HIV necessitate strategies to improve vaccine efficacy.Methods
A randomized, multi-centered, controlled, vaccine trial with three parallel groups was conducted at 12 CIHR Canadian HIV Trials Network sites. Three dosing strategies were used in HIV infected adults (18 to 60 years): two standard doses over 28 days, two double doses over 28 days and a single standard dose of influenza vaccine, administered prior to the 2008 influenza season. A trivalent killed split non-adjuvanted influenza vaccine (Fluviral™) was used. Serum hemagglutinin inhibition (HAI) activity for the three influenza strains in the vaccine was measured to assess immunogenicity.Results
297 of 298 participants received at least one injection. Baseline CD4 (median 470 cells/µL) and HIV RNA (76% of patients with viral load <50 copies/mL) were similar between groups. 89% were on HAART. The overall immunogenicity of influenza vaccine across time points and the three influenza strains assessed was poor (Range HAI ≥40 = 31–58%). Double dose plus double dose booster slightly increased the proportion achieving HAI titre doubling from baseline for A/Brisbane and B/Florida at weeks 4, 8 and 20 compared to standard vaccine dose. Increased immunogenicity with increased antigen dose and booster dosing was most apparent in participants with unsuppressed HIV RNA at baseline. None of 8 serious adverse events were thought to be immunization-related.Conclusion
Even with increased antigen dose and booster dosing, non-adjuvanted influenza vaccine immunogenicity is poor in HIV infected individuals. Alternative influenza vaccines are required in this hyporesponsive population.Trial Registration
ClinicalTrials.gov NCT00764998相似文献174.
175.
Background
Women testing positive for human papillomavirus (HPV) infection experience increased levels of anxiety that have been attributed to fears of stigmatization and developing cervical cancer. The objective of this study was to investigate the association between HPV infection and anxiety in women who were unaware they had been tested specifically for HPV, to determine if any anxiety experienced by HPV-positive women could be due to causes other than learning of test results.Methods
This study was nested within a randomised controlled trial of management of women with abnormal cervical cytology conducted in the United Kingdom with recruitment between 1999 and 2002. At baseline, prior to having a sample taken for HPV testing, the results of which were not disclosed, women were assessed for anxiety using the Hospital Anxiety and Depression Scale and asked about fears of developing cervical cancer (“cancer worries”); this assessment was repeated at 12, 18, 24, and 30 months of follow-up. Logistic regression and generalized estimating equations were used for the cross-sectional (baseline) and longitudinal analyses, respectively.Results
Among the 2842 participants, there was no association between HPV status and anxiety among white women. Among non-white women, however, anxiety was less common among HPV-positive than HPV-negative women (adjusted odds ratio 0.41, 95% confidence interval 0.22 to 0.77). Among non-smokers, cancer worry was more common in HPV-positive than HPV-negative women; the opposite association was observed among ex-smokers.Conclusions
Associations between HPV status and anxiety may be explained by factors other than learning of test results and may vary by ethnicity and lifestyle factors. 相似文献176.
刘博苏文静马力潘蕾连建奇黄长形白雪帆 《现代生物医学进展》2011,11(5):812-814
目的:研究大剂量HBsAg对HBV转基因小鼠其T细胞免疫效果的影响。方法:用大剂量血源性HBsAg免疫HBV转基因小鼠,采用ELISA方法观察转基因小鼠所诱生的HBsAg特异性Th1类细胞因子的水平,ELISPOT方法检测不同免疫方案对小鼠HBsAg特异性分泌IFN-γT细胞数量的影响,同时检测对小鼠淋巴细胞增殖的影响。结果:HBsAg组免疫后脾细胞产生的Th1类细胞因子(IFN-γ、IL-2)、HBsAg特异性分泌IFN-γT细胞及T细胞增殖水平较对照组显著增加(P<0.05)。结论:大剂量的HBs-Ag可以诱导乙肝转基因小鼠产生高水平Th1类细胞因子并打破免疫耐受。 相似文献
177.
Inoue M Sawada N Shimazu T Yamaji T Iwasaki M Sasazuki S Tsugane S;Japan Public Health Center-based Prospective Study Group 《Cancer epidemiology》2011,35(3):250-253
The recent tendency of Japanese towards greater acceptance of being informed that they have cancer, along with the growing understanding and use of informed consent, appears to have improved the accuracy of self-reported cancer. To clarify the recent validity of self-reports, we measured the sensitivity and positive predictive value of self-reported cancer among a Japanese population. Using a 10-year follow-up questionnaire conducted in 2000-2004 and the cancer registry of the JPHC Study cohort (n=93,680), we calculated the sensitivity and positive predictive value of self-reported cancer diagnoses over 10 years. Sensitivity and positive predictive value of total self-reported cancer diagnoses were 53% and 60%, respectively, but varied by site, at 62% and 52% for stomach, 38% and 47% for colorectum, 57% and 46% for lung, 34% and 31% for liver, 82% and 58% for breast, and 59% and 22% for uterus, respectively. Sensitivity was considerably improved from that in the previous report (36%), which tested for 1990-1995, but was still not considered satisfactory. Self-reported diagnoses of cancer do not provide sufficient accuracy for the detection and classification of incident cancers. Our findings may be extrapolated to other Japanese populations. 相似文献
178.
SEA-ORCHID Study Group Lumbiganon P McDonald SJ Laopaiboon M Turner T Green S Crowther CA 《PloS one》2011,6(9):e23994
Background
Maternal and neonatal mortality and morbidity remain unacceptably high in many low and middle income countries. SEA-ORCHID was a five year international collaborative project in South East Asia which aimed to determine whether health care and health outcomes for mothers and babies could be improved by developing capacity for research generation, synthesis and use.Methods
Nine hospitals in Indonesia, Malaysia, the Philippines and Thailand participated in SEA-ORCHID. These hospitals were supported by researchers from three Australian centres. Health care practices and outcomes were assessed for 1000 women at each hospital both before and after the intervention. The capacity development intervention was tailored to the needs and context of each hospital and delivered over an 18 month period. Main outcomes included adherence to forms of care likely to be beneficial and avoidance of forms of care likely to be ineffective or harmful.Results
We observed substantial variation in clinical practice change between sites. The capacity development intervention had a positive impact on some care practices across all countries, including increased family support during labour and decreased perineal shaving before birth, but in some areas there was no significant change in practice and a few beneficial practices were followed less often.Conclusion
The results of SEA-ORCHID demonstrate that investing in developing capacity for research use, synthesis and generation can lead to improvements in maternal and neonatal health practice and highlight the difficulty of implementing evidence-based practice change. 相似文献179.
Avila-Ríos S García-Morales C Garrido-Rodríguez D Ormsby CE Hernández-Juan R Andrade-Villanueva J González-Hernández LA Torres-Escobar I Navarro-Álvarez S Reyes-Terán G;Mexican HIV Molecular Epidemiology Project Group 《PloS one》2011,6(11):e27812
Background
Transmitted drug resistance (TDR) remains an important concern for the management of HIV infection, especially in countries that have recently scaled-up antiretroviral treatment (ART) access.Methodology/Principal Findings
We designed a study to assess HIV diversity and transmitted drug resistance (TDR) prevalence and trends in Mexico. 1655 ART-naïve patients from 12 Mexican states were enrolled from 2005 to 2010. TDR was assessed from plasma HIV pol sequences using Stanford scores and the WHO TDR surveillance mutation list. TDR prevalence fluctuations over back-projected dates of infection were tested. HIV subtype B was highly prevalent in Mexico (99.9%). TDR prevalence (Stanford score>15) in the country for the study period was 7.4% (95% CI, 6.2∶8.8) and 6.8% (95% CI, 5.7∶8.2) based on the WHO TDR surveillance mutation list. NRTI TDR was the highest (4.2%), followed by NNRTI (2.5%) and PI (1.7%) TDR. Increasing trends for NNRTI (p = 0.0456) and PI (p = 0.0061) major TDR mutations were observed at the national level. Clustering of viruses containing minor TDR mutations was observed with some apparent transmission pairs and geographical effects.Conclusions
TDR prevalence in Mexico remains at the intermediate level and is slightly lower than that observed in industrialized countries. Whether regional variations in TDR trends are associated with differences in antiretroviral drug usage/ART efficacy or with local features of viral evolution remains to be further addressed. 相似文献180.
Jongen PJ Sindic C Sanders E Hawkins S Linssen W van Munster E Frequin S Borm G;Functional Composite Quality of Life in Avonex-treated Relapsing Multiple Sclerosis Patients Study Group 《PloS one》2011,6(10):e26568