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11.
ObjectivesBisphenol A (BPA) is used in the electrical, mechanical, medical, and food industries. Previous studies have suggested that BPA is an endocrine disruptor. Regulation of BPA has led to increased use of bisphenol F (BPF) and bisphenol S (BPS). However, few studies have investigated the associations of BPF and BPS with thyroid dysfunction in children. Our study investigated the associations of prenatal BPA and early childhood BPA, BPF, and BPS exposure with thyroid function in 6-year-old children.MethodsPrenatal BPA concentrations were measured during the second trimester of pregnancy in an established prospective birth cohort. We measured urinary BPA, BPF, and BPS concentrations and thyroid hormone levels (thyroid-stimulating hormone, total T3, and free T4) in 6-year-old children (n=574). We examined the associations between urinary bisphenol concentrations and percentage change of thyroid hormone concentrations using multivariate linear regression. We also compared thyroid hormone levels by dividing the cohort according to BPA, BPF, and BPS concentrations.ResultsThe associations between prenatal BPA and total T3 levels were statistically significant in all models, except for girls when using a crude model. The associations between urinary BPA and BPS concentrations and levels of all thyroid hormones were not statistically significant. However, we observed that lower free T4 levels (−1.94%; 95% confidence interval, −3.82 to −0.03) were associated with higher urinary BPF concentrations in girls only.ConclusionsOur findings identified significant associations between prenatal BPA exposure and total T3 levels in all children and between BPF exposure and free T4 levels in girls only.  相似文献   
12.
PurposeThis study explored the association of maternal age at menarche (AAM) with pubertal timing among girls and boys in Chongqing, China.MethodsPubertal development of 1,237 children (542 girls and 695 boys) were examined half-yearly through inspection and palpation from April 2014 to June 2019. Characteristics of parents and maternal AAM were collected by a parental questionnaire at baseline. Maternal AAM was used both as a continuous and a categorical variable in Cox regression models.ResultsA total of 1,198 children (528 girls and 670 boys) were included in the study. In the simple Cox model, earlier maternal AAM was associated with girls' earlier menarche, breast and pubic hair development, and boys' first ejaculation, testicular development, and genital development. When adjusting for children's body mass index z-scores (BMIz) and socioeconomic covariates, we found that girls whose mothers had early AAM had a higher risk of earlier onset of menarche (hazard ratio [HR]: .922, 95% confidence interval [CI]: .852–.998 for continuous maternal AAM, HR: 1.297, 95% CI: 1.041–1.616 for maternal AAM ≤13 years), and boys whose mother achieved menarche earlier experienced a higher risk of earlier onset of first ejaculation (HR: .896, 95% CI: .830–.968). Children's BMIz were related to all nine pubertal milestones. Parental education and relationship, birth weight, parity, and family type were also associated with pubertal timing.ConclusionsEarlier maternal AAM was related to earlier pubertal timing in both girls and boys in Chongqing, especially girls' age at menarche and boys' first ejaculation. Children's BMIz was the most consistent factor for pubertal timing. Children's BMIz and socioeconomic conditions had greater influence on most pubertal milestones than maternal AAM.  相似文献   
13.
BackgroundHyperinsulinemia and inflammation are inter-related pathways that link diet with the risk of several chronic diseases. Evidence suggests that these pathways may also increase prostate cancer risk.ObjectiveTo determine whether hyperinsulinemic diet and inflammatory diet are associated with prostate cancer incidence and mortality.Design, setting, and participantsWe prospectively followed 41 209 men in the Health Professionals Follow-up Study (1986–2014). Scores for two validated dietary patterns were calculated from food frequency questionnaires at baseline and updated every 4 yr.Outcome measurements and statistical analysisTotal, advanced, and lethal prostate cancer outcomes were assessed. Multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were determined for associations between two empirical hypothesis-oriented dietary patterns—empirical dietary index for hyperinsulinemia and empirical dietary inflammatory pattern—and prostate cancer risk estimated using Cox proportional hazard regression.Results and limitationsDuring 28 yr of follow-up, 5929 incident cases of total prostate cancer, including 1019 advanced and 667 fatal, were documented. In multivariable-adjusted models, there was a 7% higher risk of advanced prostate cancer (HR: 1.07; 95% CI: 1.01–1.15) and a 9% higher risk of fatal prostate cancer (HR: 1.09; 95% CI: 1.00–1.18) per standard deviation (SD) increase in the hyperinsulinemic diet. When stratified by age, the hyperinsulinemic diet was associated with only earlier-onset aggressive prostate cancer (men under 65 yr), with per SD HRs of 1.20 (95% CI: 1.06–1.35) for advanced, 1.22 (1.04–1.42) for fatal, and 1.20 (1.04–1.38) for lethal. The inflammatory diet was not associated with prostate cancer risk in the overall study population, but was associated with earlier-onset lethal prostate cancer (per SD increase HR: 1.16; 95% CI: 1.00–1.35).ConclusionsHyperinsulinemia and inflammation may be potential mechanisms linking dietary patterns with the risk of aggressive prostate cancer, particularly earlier-onset disease.Patient summaryAvoiding inflammatory and hyperinsulinemic dietary patterns may be beneficial for the prevention of clinically relevant prostate cancer, especially among younger men.  相似文献   
14.
15.
ObjectiveUveitis is a frequent extra rheumatological manifestation in axial Spondyloarthritis (SpA). The aim of study was to evaluate the prevalence and incidence of uveitis over the first five years of a prospective nationwide cohort of patients with high suspicion of early axial SpA, and to evaluate its associated factors.MethodsDESIR is a prospective observational cohort of patients with recent onset inflammatory back pain (more than 3 months, less than 3 years), suggestive of axial SpA, All available factors in the database were compared between patients with and without uveitis at 5 years, by uni and then multivariate analysis. Baseline factors associated with new cases of uveitis occurrence over the 5 years were also analyzed. Significance: P less than 0.05.ResultsAfter 5 years, 91 patients (out of 480 with complete follow-up) had at least one uveitis episode, giving an estimated prevalence of 18.9% [95% CI: 15.4–22.4]. In multivariate analysis, uveitis was significantly associated with dactylitis, and elevated ESR. New incident uveitis occurred in 31 cases over 5 years, giving an estimated incidence rate of 1.29 [0.84–1.74]/100 patient-years. Incidence of new uveitis was associated in multivariate analysis with baseline factors: diagnosis of SpA, sacro iliac MRI inflammatory SPARCC score, dactylitis, syndesmophyte score. No significant association was found with HLA-B27, DMARDs, BASDAI, ASDAS, BASFI.ConclusionFive-years data of the DESIR cohort allowed an estimation of incidence rate of uveitis of 1.3/100p-y; over five years, uveitis was associated with dactylitis, biologic and sacro iliac MRI inflammation.  相似文献   
16.
17.
To assess the effect of smoking on bone mineral density (BMD) at different life stages, to examine whether the effect of smoking differs between men and women, and to discover whether its effect in women differs according to history of estrogen use, a cohort study was carried out with single cross-section measurement of BMD by single and dual photon absorptiometry. The setting was the Framingham Study, a population-based cohort study with over 40 years prospectively collected data on smoking. Subjects (n=1164) consisted of cohort members participating in the 20th biennial Framingham examination (1988–1989). The measurements included in the study were BMD measured at the hip, spine and radius, smoking history ascertained at all Framingham Study examinations since 1948, and other factors affecting BMD (age, weight, estrogen use, caffeine use, alcohol use and physical activity). Neither current smoking, recent (last 10 years) smoking, nor early adulthood smoking resulted in significantly lower BMD at any skeletal site among women who had not taken estrogen. Among women who had taken estrogen, BMD at most sites was lower among current or recent smokers, although the small numbers of smokers made it difficult to find significant differences at all skeletal sites. Among men, a consistently lower BMD at all skeletal sites was observed for smokers regardless of when in their life they smoked (4–15.3% lower), although the effect of smoking during early adulthood was of a lesser magnitude (4–8% lower). Former male smokers who had quit <10 years ago had lower BMD than men who had quit 10 years ago. In conclusion, in women who had used estrogen, BMD was lower in current or recent smokers than it was in non-smokers. In men, smoking at any stage of life had adverse effects on the skeleton that was independent of weight, alcohol or caffeine use, implying other mechanisms for smoking's effect on bone.  相似文献   
18.
The last international consensus conference about hepatitis C virus (HCV) treatment emphasized the importance of treatment for persons coinfected with HCV and human immunodeficiency virus (HIV). As liver biopsy precedes treatment, we aimed to identify factors associated with the performance of liver biopsy among HIV-HCV coinfected drug users during a 5-year follow-up to study their access to HCV treatment. Of the 296 patients followed in the HIV hospital departments of Nice and Marseilles and with retrievable records about HCV diagnosis and care, 166 were eligible for analysis having had detectable HCV RNA at least once during the study period. Overall, 45.2% of patients underwent liver biopsy during follow-up. Using proportional hazard models, predictors of having had a liver biopsy were high social support, complete abstinence from drug injection, and lack of immunosuppression as well as male gender, no history of multiple incarcerations, more recent onset of drug use, and an increase of liver enzyme levels. These results suggest that specific efforts should be devoted to HIV-HCV coinfected drug users to assist with stabilizing these patients to optimize their access to HCV care whenever possible. The MANIF 2000 study group includes C. Boirot, A. D. Bouhnik, M. P. Carrieri, J. P. Cassuto, M. Chesney, P. Dellamonica, P. Dujardin, S. Duran, J. G. Fuzibet, H. Gallais, J. A. Gastaut, G. Lepeu, D. A. Loundou, C. Marimoutou, D. Mechali, J. P. Moatti, J. Moreau, M. Nègre, Y. Obadia, I. Poizot-Martin, C. Pradier, D. Rey, C. Rouzioux, A. Sobel, B. Spire, F. Trémolières, and D. Vlahov.  相似文献   
19.
目的 比较接尘、吸烟对呼吸系统疾病死亡的影响.方法 在1989年至1992年广州建立职业健康监护档案的基础上对30岁以上、职业接触粉尘和无粉尘接触的80 987名工人进行前瞻性队列研究.结果 (1)队列平均年龄43.5岁,职业性粉尘接触率16.3%,吸烟率43.7%,饮酒率33.5%.(2)队列平均随访8年,35人失访,失访率0.04%,总死亡1 593人中,219人死于肺癌,90人死于非恶性肿瘤性呼吸系统疾病.(3)调整相关因素后,相对于不吸烟者,吸烟者肺癌死亡相对危险度(RR)为3.32,是粉尘接触者相对于无粉尘接触者肺癌死亡RR(1.53)的2.2倍.粉尘接触者非恶性肿瘤性呼吸系统疾病死亡RR为2.41,是吸烟者(1.89)的1.28倍.尤其是矽尘接触者,其非恶性肿瘤性呼吸系统疾病死亡RR为5.72,是吸烟者的3.03倍.既接触粉尘又吸烟,呼吸系统疾病死亡RR增加更明显.(4)男性吸烟者呼吸系统疾病死亡危险分别随日吸烟量、烟龄的增加而增加.结论 职业接触粉尘和吸烟均可引致超额的呼吸系统疾病死亡,两者存在协同作用.吸烟致肺癌死亡RR高于接尘,而致非恶性肿瘤性呼吸系统疾病死亡RR则低于接尘.吸烟与呼吸系统疾病死亡危险存在明显的剂量-效应关系.  相似文献   
20.
目的探讨红点黄本对小学生远视力的保护作用,为学生用簿本标准的制订提供依据。方法整群抽取大连市某小学二年级学生131名为试验组6、35名为对照组,追踪观察3 a。观察指标为受试者的双眼远视力。结果试验组远视力以保持“不变”为主(43.9%),比对照组(21.2%)多1倍;远视力下降3~5行的,对照组(合计20.3%)各分别比试验组约多1倍;下降6行及以上者,试验组为0,而对照组占4.5%。试验组的右眼远视力3 a间平均下降0.034 4,而对照组下降0.095 1(t=3.731,P=0.000);试验组的左眼远视力平均下降0.044 3,而对照组下降0.081 1(t=2.247,P=0.025)。结论红点黄本对城市小学生的远视力有保护作用。  相似文献   
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