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《Vaccine》2020,38(32):4940-4943
To determine the duration of immunity provided by the Hepatitis A vaccination (HepA), we evaluated a cohort of participants in Alaska 20 years after being immunized as infants. At recruitment, participants received two doses of inactivated HepA vaccine on one of three schedules. We conducted hepatitis A antibody (anti-HAV) testing for participants at the 20-year time-point. Seventy-five of the original 183 participants (41%) were available for follow-up. The overall anti-HAV geometric mean concentration was 29.9 mIU/mL (95% CI 22.4 mIU/mL, 39.7 mIU/mL) and 50 participants (68%) remained seropositive (titer ≥ 20 mIU/mL). Using a fractional polynomial model, the predicted percent seropositive at 25 years was 55.3%, 49.8% at 30 years and 45.7% at 35 years, suggesting that the percent sero-positive could drop below 50% earlier than previously expected. Further research is necessary to understand if protection continues after seropositivity diminishes or if a HepA booster dose may become necessary.  相似文献   
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The chemokine receptors CCR5 and CXCR4 are an obvious target for HIV therapies. Two compounds, T-22 and AMD-3100, have been shown to inhibit infection of CXCR4-using HIV-1 isolates. The specificity of T-22 and AMD-3100 was further confirmed by their ability to block entry of HIV-1 in GHOST-CXCR4 transfected cells with no effect on viral entry in the GHOST-CCR5 cells. The ability of T-22 to block replication of diverse HIV-1 isolates (group M, subtypes A, B, D, E, and F as well as group O) and HIV-2 primary isolates with varying coreceptor specificities ranging from exclusive CCR5 usage to multiple coreceptor usage was examined in detail. T-22 was found to be highly effective (>90%) at blocking infection of diverse HIV-1 (subtypes A-F, and group O) and HIV-2 isolates that use multiple coreceptors in human PBMCs homozygous for a 32-bp deletion in CCR5 (CCR5-/-), but less effective in CCR5 +/+ PBMCs. Additionally, sequential primary HIV-1 isolates obtained from a longitudinal cohort who had switched from single coreceptor usage to a broad range of multiple receptors could be blocked effectively by both T-22 and AMD-3100 in CCR5-/- PBMCs. Our data suggest that CXCR4 antagonistic compounds are highly effective in blocking the entry of X4-tropic HIV-1, and that these compounds could be a useful additive to current anti-retroviral therapy for clinical management of HIV disease.  相似文献   
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目的 分析2005—2020年盐城市丙肝病例报告资料,总结丙肝流行特征,为盐城市丙肝防制工作提供参考依据。方法 收集各年度丙肝报告病例和人口学资料,采用Excel 2016软件汇总并作描述性统计分析。采用Joinpoint regression program(JRP)4.9.0.0软件对丙肝年发病率进行趋势检验,采用SPSS 25.0软件和ArcGIS 10.6软件对病例数据进行统计分析。结果 2005—2020年盐城市累计报告丙肝病例2 555例,年报告发病率整体呈平缓增长趋势,最低为2005年的0.42/10万,最高为2019年的5.84/10万。年度变化百分比(annual percent change,APC)为14.5% (95% CI: 11.5%~17.6%),P<0.01。除2019年外,其余各年丙肝疫情呈散发状态,无明显季节特征。报告病例数位居前三位的地区是亭湖区、滨海县以及东台市,分别占比19.77% (505/2 555)、14.01%(358/2 555)以及12.92%(330/2 555)。男女报告病例数比为1.33[DK]∶1,发病率最高的年龄组为70~79岁年龄组(56.94/10万)。农民为报告病例数最多的人群,占比59.33%(1 516/2 555)。确诊病例2 204例,临床诊断病例332例。结论 盐城市丙肝疫情呈上升趋势。全市应进一步扩大丙型肝炎病毒检测,加强丙肝防治宣传教育和完善社会医疗保障政策来提高丙肝治疗的可及性和可负担性,同时应进一步加强对于丙肝疫情的监测以及规范丙肝的诊疗,并对重点地区、重点人群开展精准的综合干预工作。  相似文献   
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目的 分析浙江省MSM网络临时性伴的HIV感染状况知情交友(知情交友)状况及相关因素,为干预措施制定提供参考依据。方法 2018年6-12月在杭州市、宁波市、温州市、台州市和绍兴市,由社会组织和自愿咨询与检测门诊招募符合研究对象标准的MSM,招募样本量为793人。采用自行设计问卷,采用面对面方式问卷调查,收集社会人口学特征、艾滋病知识、性行为、知情交友行为等信息。采用SPSS 20.0软件进行统计学分析。结果 在MSM 767人中,最近6个月发生网络临时性行为302人,发生网络型临时性行为、网络/场所混合型临时性行为者分别占62.6%(189/302)和37.4%(113/302)。在网络临时性伴的知情交友中,已告知、已询问和已知晓者分别占54.6%(165/302)、49.2%(146/297)和42.9%(82/191),知晓网络临时性伴HIV阴性状况后坚持使用安全套者占75.8%(113/149)。多因素logistic回归分析结果显示,最近6个月网络临时性伴的知情交友中未询问的相关因素包括年龄25~34岁(aOR=2.17,95%CI:1.20~3.91)、最近6个月网络临时性伴数>2个(aOR=2.13,95%CI:1.27~3.57)、不认为网络临时性伴HIV感染风险较高(aOR=1.96,95%CI:1.14~3.35)、既往HIV检测数>1次(aOR=0.38,95%CI:0.22~0.66)。结论 浙江省MSM网络临时性伴的知情交友的意愿较高,但知情交友行为及知晓对方HIV检测结果的比例较低,针对MSM的网络临时性伴较多、认为网络临时性伴感染风险低和HIV检测次数较少者,需加强健康教育和促进知情交友的行为干预。  相似文献   
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Kevin M. De Cock, MD; Mary Glenn Fowler, MD, MPH; Eric Mercier, MD, MPH; Isabelle de Vincenzi, MD, PhD; Joseph Saba, MD; Elizabeth Hoff, MSc; David J. Alnwick, MSc; Martha Rogers, MD; Nathan Shaffer, MD

JAMA. 2000;283:1175-1182.

Each year, an estimated 590,000 infants acquire human immunodeficiency virus type 1 (HIV) infection from their mothers, mostly in developing countries that are unable to implement interventions now standard in the industrialized world. In resource-poor settings, the HIV pandemic has eroded hard-won gains in infant and child survival. Recent clinical trial results from international settings suggest that short-course antiretroviral regimens could significantly reduce perinatal HIV transmission worldwide if research findings could be translated into practice. This article reviews current knowledge of mother-to-child HIV transmission in developing countries, summarizes key findings from the trials, outlines future research requirements, and describes public health challenges of implementing perinatal HIV prevention interventions in resource-poor settings. Public health efforts must also emphasize primary prevention strategies to reduce incident HIV infections among adolescents and women of childbearing age. Successful implementation of available perinatal HIV interventions could substantially improve global child survival.

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PurposeFarm youth continue to experience high rates of injury and deaths as a result of agricultural activities. Farm machinery, especially tractors, is the most common cause of casualties to youth. A Roll-Over Protection Structure (ROPS) along with a fastened seatbelt can prevent almost all injuries and fatalities from tractor overturns. Despite this knowledge, the use of seatbelts by farmers on ROPS tractors remains low. This study treats farm safety as a family issue and builds on the central role of parents as teachers and role models of farm safety for youth.MethodsThis research study used a longitudinal, repeated-measures, randomized-control design in which youth 10–19 years of age were randomly assigned to either of two intervention groups (parent-led group and staff-led group) or the control group.ResultsFathers in the parent-led group were less likely to operate ROPS tractors without a seatbelt compared with other groups. They were more likely to have communicated with youth about the importance of wearing seatbelts on ROPS tractors. Consequently, youth in the parent-led group were less likely to operate a ROPS tractor without a seatbelt than the control group at post-test.ConclusionsThis randomized control trial supports the effectiveness of a home-based, father-led farm safety intervention as a promising strategy for reducing youth as well as father-unsafe behaviors (related to tractor seatbelts) on the farm. This intervention appealed to fathers' strong motivation to practice tractor safety for the sake of their youth. Involving fathers helped change both father as well as youth unsafe tractor-seatbelt behaviors.  相似文献   
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