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Data are presented from the Baltimore Young Men’s Survey, a cross-sectional, venue-based sample survey of risks associated with HIV and report of a prior HIV test, conducted between 1996 and 2000, and enrolling 843 young men who have sex with men (MSM) aged 15–29 years. HIV prevalence was 12.1% overall and racial disparities in HIV prevalence were pronounced (range, 2.9% among non-Hispanic whites to 27.1% among non-Hispanic blacks). Risks independently associated with being HIV-positive were: being between 26 and 29 years of age, being non-Hispanic black or of other/mixed race, having had 20 or more lifetime male sex partners, having been diagnosed with a sexually transmitted disease (STD), and not being currently enrolled in school. The majority of participants (78.9%) reported a prior HIV test. In multivariate analysis, being older, having had five or more lifetime male sex partners, having had anal intercourse with males, reporting an STD diagnosis, and reporting recent unprotected anal sex were associated with report of a prior HIV test. Prevention efforts must address high HIV prevalence among young non-Hispanic black MSM and must make testing and effective counseling for young MSM readily available.  相似文献   
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Systemic lupus erythematosus (SLE) is a multisystemic autoimmune disorder. Renal involvement has the worst prognosis. However, renal cortical necrosis is extremely unusual in SLE. In this case report, we describe the autopsy findings in a young female patient with SLE presenting with renal failure. At autopsy, there was Libmann–Sacks endocarditis with multiorgan infarcts and renal cortical necrosis. Secondary antiphospholipid antibodies contribute to the cardiac and renal manifestations in SLE. We discuss the incidence and pathogenesis of endocarditis with differential diagnosis for cortical necrosis in a patient of SLE.  相似文献   
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Porcine circovirus (PCV) appeared in 1974 as an unidentified, innocuous viral inhabitant of cell cultures and pigs. Today PCV1 is a contaminant of some human vaccines, and PCV2 is a major pathogen of swine. PCV1 is reportedly ubiquitous in swine but nonpathogenic. Since the interplay of PCV1 and PCV2 in swine might explain variable disease results and shed light on the potential for human exposure, we analyzed in depth the prevalence of PCV1 and PCV2 infection and exposure in the U.S. finishing swine herd. Over 82% of sera from 185 farms were positive for PCV2 by PCR, whereas only 2.4% were positive for PCV1. More than 80% of PCV2 DNA-positive swine were also positive for anti-PCV2 antibodies. PCV1 was only rarely present. Exposure of swine, and therefore humans via pigs, to PCV1 is negligible. We conclude that PCV2 causes a persistent infection in pigs and that PCV1 is absent or rare in swine.  相似文献   
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Background

Estrogen is the leading etiologic factor for endometrial cancer. Estrogen-induced proliferation of endometrial epithelial cells normally requires paracrine growth factors produced by stromal cells. Epidemiologic evidence indicates that dietary soy prevents endometrial cancer, and implicates the phytoestrogen genistein in this effect. However, results from previous studies are conflicting regarding the effects of genistein on hormone responsive cancers.

Methods

The effects of estrogen and genistein on proliferation of Ishikawa (IK) endometrial adenocarcinoma cells were examined in co-cultures of IK cells with endometrial stromal cells, recapitulating the heterotypic cell-to-cell interactions observed in vivo. The roles of estrogen receptor (ER)α and ERβ were evaluated using ERα and ERβ specific agonists. ER activation and cell proliferation in the IK epithelial cells were determined by alkaline phosphatase assay and Coulter counter enumeration, respectively.

Results

Both estrogen and genistein increased estrogen receptor-induced gene activity in IK cells over a range of concentrations. Estrogen alone but not genistein increased IK proliferation in co-cultures. When primed by estrogen treatment, increasing concentrations of genistein produced a biphasic effect on IK proliferation: nM concentrations inhibited estrogen-induced proliferation while μM concentrations increased proliferation. Studies with an ERβ-specific agonist produced similar results. Genistein did not influence the effects of estrogen on IK proliferation in monoculture.

Conclusions

Our study indicates that nutritionally relevant concentrations (nM) of genistein inhibit the proliferative effects of estrogen on endometrial adenocarcinoma cells presumably through activation of stromal cell ERβ. We believe that sub-micromolar concentrations of genistein may represent a novel adjuvant for endometrial cancer treatment and prevention.  相似文献   
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IntroductionDaily and event‐driven PrEP are both efficacious in reducing the risk for HIV infection. However, the practice of event‐driven PrEP (edPrEP) is less well studied, in particular when provided as an alternative to daily PrEP. We studied regimen preferences and switches, and sexually transmitted infection (STI) incidence.MethodsWe analysed pooled data from two prospective cohort studies among MSM: Be‐PrEP‐ared, Belgium and AMPrEP, the Netherlands. In both projects, participants could choose between daily and edPrEP at three‐monthly study visits, when they were also screened for sexually transmitted infections including hepatitis C (HCV). We assessed the proportion choosing each regimen, and the determinants of choosing edPrEP at baseline. Additionally, we compared the incidence rates (IRs) of HCV, syphilis and chlamydia or gonorrhoea between regimens using Poisson regression. The study period was from 3 August 2015 until 24 September 2018.Results and discussionWe included 571 MSM, of whom 148 (25.9%) chose edPrEP at baseline. 31.7% of participants switched regimen at least once. After 28 months, 23.5% used edPrEP. Older participants (adjusted odds ratio (aOR) = 1.38 per 10 years, 95% confidence interval (CI) = 1.15 to 1.64) and those unemployed (aOR = 1.68, 95% CI = 1.03 to 1.75) were more likely to initially choose edPrEP. IR of HCV and syphilis did not differ between regimens, but the IR of chlamydia/gonorrhoea was higher among daily users (adjusted incidence rate ratio = 1.61, 95% CI = 1.35 to 1.94).ConclusionsA quarter of participants chose edPrEP at baseline and at 28 months this proportion was similar. Although the IR of HCV and syphilis were similar in the two regimens, the lower incidence of chlamydia and gonorrhoea among edPrEP users may suggest that less frequent STI testing of this group could be considered.  相似文献   
90.
Chow WS  Cheung BM  Tso AW  Xu A  Wat NM  Fong CH  Ong LH  Tam S  Tan KC  Janus ED  Lam TH  Lam KS 《Hypertension》2007,49(6):1455-1461
Low circulating levels of adiponectin, an adipokine with insulin-sensitizing, antiatherogenic, and anti-inflammatory properties, are found in hypertensive patients. Adiponectin replenishment ameliorated hypertension in adiponectin-deficient mice or obese, hypertensive mice with hypoadiponectinemia, suggesting an etiologic role of adiponectin in hypertension. We aimed to determine, in this 5-year prospective study, whether hypoadiponectinemia could predict the development of hypertension in a nondiabetic Chinese cohort. A total of 577 subjects (249 men and 328 women) were recruited from the population-based Hong Kong Cardiovascular Risk Factor Prevalence Study and prospectively followed up for 5 years. The relationship of serum adiponectin with the development of hypertension (sitting blood pressure >or=140/90 mm Hg) was investigated in a nested case-control study consisting of 70 subjects who had developed hypertension on follow-up and 140 age- and sex-matched control subjects who were normotensive both at baseline and at year 5. At baseline, serum adiponectin level in the lowest sex-specific tertile was more likely to be associated with hypertension (P=0.003 versus the highest tertile, after adjusting for age, body mass index, fasting insulin, and high-sensitivity C-reactive protein). At year 5, baseline serum adiponectin was a significant independent predictor of incident hypertension in the nested case-control study (P=0.015; age adjusted), together with mean arterial pressure (P<0.001), high-sensitivity C-reactive protein (P=0.018), and body mass index (P=0.004). Normotensive subjects with baseline serum adiponectin levels in the lowest sex-specific tertile had an increased risk of becoming hypertensive (adjusted odds ratio: 2.76; 95% CIs: 1.06 to 7.16; P=0.037 versus highest tertile). Our data suggest that hypoadiponectinaemia may be involved in the pathogenesis of hypertension in humans.  相似文献   
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