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981.
While public health remains the primary site of authority for preventing HIV transmission, recent shifts in the biopolitics of HIV have heightened tensions in the institutional and discursive relations through which the sexual lives of people living with HIV and broader HIV epidemics are regulated. Most notably, over the past decade, criminal justice responses to HIV have gained considerable traction. The growing use of the criminal law to regulate perceived HIV transmission risks has occasioned considerable controversy among people living with HIV, community-based AIDS organizations, health-care providers, public health authorities, prosecutors, judges, and the legal community. This article introduces a special section of Critical Public Health focused on the public health implications of HIV criminalization. The article reviews past and current work on the topic, situates the contributions made by the articles published in the special section, and outlines directions for future inquiry.  相似文献   
982.
983.
984.
ObjectiveTo evaluate the effect of a smoking ban in high schools on smoking behaviour among Chilean students.MethodsWe conducted an interrupted time-series analysis, using repeated cross-sectional data from Chile’s school population survey (2000–2011) for high-school students aged 12–18 years and a control group of persons aged 19–24 years. Poisson regression models were used to assess trends in smoking behaviour before and after the policy changes. The outcome measures were self-reported smoking prevalence (any smoking in the past month) and high frequency of smoking (smoking 15 days or more per month).FindingsFrom 2005 to 2011, the prevalence of smoking declined among high-school students by 6.8% per year compared with 3.6% decline per year in the control group. The decline in the target group was 2.9% (95% confidence interval, CI: 0.18 to 5.00) greater. We estimated that 5–6 years after enforcing the law, smoking prevalence among high-school students was 13.7% lower as a result of the ban. The impact of the smoking ban was primarily driven by declines in smoking prevalence among students in grades 8 to 10. The smoking ban did not significantly alter the frequency of smoking.ConclusionThe 2005 school smoking ban reduced smoking prevalence among younger high-school students in Chile. Further interventions targeting older individuals and frequent smokers may be needed.  相似文献   
985.

Objective

To propose two new indicators for monitoring access to antiretroviral treatment (ART) for human immunodeficiency virus (HIV); (i) the time from HIV seroconversion to ART initiation, and (ii) the time from ART eligibility to initiation, referred to as delay in ART initiation. To estimate values of these indicators in Cameroon.

Methods

We used linear regression to model the natural decline in CD4+ T-lymphocyte (CD4+ cell) numbers in HIV-infected individuals over time. The model was fitted using data from a cohort of 351 people in Côte d’Ivoire. We used the model to estimate the time from seroconversion to ART initiation and the delay in ART initiation in a representative sample of 4154 HIV-infected people who started ART in Cameroon between 2007 and 2010.

Findings

In Cameroon, the median CD4+ cell counts at ART initiation increased from 140 cells/μl (interquartile range, IQR: 66 to 210) in 2007–2009 to 163 cells/μl (IQR: 73 to 260) in 2010. The estimated average time from seroconversion to ART initiation decreased from 10.4 years (95% confidence interval, CI: 10.3 to 10.5) to 9.8 years (95% CI: 9.6 to 10.0). Delay in ART initiation increased from 3.4 years (95% CI: 3.1 to 3.7) to 5.8 years (95% CI: 5.6 to 6.2).

Conclusion

The estimated time to initiate ART and the delay in ART initiation indicate that progress in Cameroon is insufficient. These indicators should help monitor whether public health interventions to accelerate ART initiation are successful.  相似文献   
986.
Archives of Sexual Behavior - Online partner seeking is associated with sexual risk behavior among young adults (specifically men who have sex with men), but this association has yet to be explored...  相似文献   
987.
ObjectivesPatient-physician language concordance among limited English proficient (LEP) patients is associated with better outcomes for specific clinical conditions. Whether or not language concordance contributes to use of specific preventive care services is unclear.MethodsWe pooled data from the 2007 and 2009 California Health Interview Surveys to examine mammography, colorectal cancer (CRC) screening, and influenza vaccination use among self-identified LEP Latino and Asian (i.e., Chinese, Korean, and Vietnamese) immigrants. We defined language concordance by respondents reporting that their physician spoke their non-English language. Analyses were completed in 2013–2014.ResultsLanguage concordance did not appear to facilitate mammography use among Latinas (adjusted odds ratio [AOR] = 1.02, 95% confidence interval [CI] 0.72, 1.45). Among Asian women, we could not definitively exclude a negative association of language concordance with mammography (AOR=0.55, 95% CI 0.27, 1.09). Patient-physician language concordance was associated with lower odds of CRC screening among Asians but not Latinos (Asian AOR=0.50, 95% CI 0.29, 0.86; Latino AOR=0.85, 95% CI 0.56, 1.28). Influenza vaccination did not differ by physician language use among either Latinos or Asians.ConclusionsPatient-physician language concordance was not associated with higher use of mammography, CRC screening, or influenza vaccination. Language concordance was negatively associated with CRC screening among Asians for reasons that require further research. Future research should isolate the impact of language concordance on the use of preventive care services from health system factors.Language barriers in health care may reduce the quality of care received by limited English proficient (LEP) patients, serve as a hurdle to the receipt of preventive care services, and contribute to health disparities.13 Patient-physician communication is enhanced by language concordance (i.e., when the physician is fluent in the patient''s non-English language). Language concordant care is associated with patient trust in physicians and greater satisfaction,4,5 increased medication adherence,6 and higher rates of glycemic control among diabetic patients.7 In contrast, language barriers are not associated with other conditions, such as mortality or length of stay in patients with myocardial infarction.8Latinos and Asians are the fastest-growing racial/ethnic minority groups in the United States.9 Preventive care services use, such as mammography for breast cancer screening, colorectal cancer (CRC) screening, and influenza vaccination, are suboptimal in both populations.1016 Studies of the association between patient-physician language concordance and completion of preventive care practices report inconsistent findings. Prior work, while limited in scope, suggests that language concordance may be negatively associated with receipt of CRC screening and positively associated in some groups with mammography and influenza vaccination.1720 However, this work has been limited by sampling selection and by significant variation in key definitions such as LEP or language concordance itself.1820The California Health Interview Survey (CHIS) includes representative samples of major racial/ethnic minority groups and is conducted in multiple languages including English, Spanish, Mandarin, Cantonese, Korean, and Vietnamese. We used CHIS to examine the associations between patient report of patient-physician language concordance and patient report of use of mammography, CRC screening, and influenza vaccination among LEP Latino and Asian Americans in California.  相似文献   
988.
Objectives. We examined correlations between gender, race, sexual identity, and technology use, and patterns of cyberbullying experiences and behaviors among middle-school students.Methods. We collected a probability sample of 1285 students alongside the 2012 Youth Risk Behavior Survey in Los Angeles Unified School District middle schools. We used logistic regressions to assess the correlates of being a cyberbully perpetrator, victim, and perpetrator–victim (i.e., bidirectional cyberbullying behavior).Results. In this sample, 6.6% reported being a cyberbully victim, 5.0% reported being a perpetrator, and 4.3% reported being a perpetrator–victim. Cyberbullying behavior frequently occurred on Facebook or via text messaging. Cyberbully perpetrators, victims, and perpetrators–victims all were more likely to report using the Internet for at least 3 hours per day. Sexual-minority students and students who texted at least 50 times per day were more likely to report cyberbullying victimization. Girls were more likely to report being perpetrators–victims.Conclusions. Cyberbullying interventions should account for gender and sexual identity, as well as the possible benefits of educational interventions for intensive Internet users and frequent texters.Cyberbullying is the “willful and repeated harm inflicted [on another] through the use of computers, cell phones, or other electronic devices.”1(p5) Among 6th- through 10th-grade students nationally, 4% reported being cyberbullying perpetrators, 5% reported being a victim of cyberbullying, and 5% reported being perpetrators–victims (meaning that they have both perpetrated and been victimized by cyberbullying) during the previous 2 months.2 Among middle-school students in the southeastern and northwestern United States, a nonprobability sample of 3767 students by Kowalski and Limber3 found that 11% reported being a victim of cyberbullying, 4% were cyberbullying perpetrators, and 7% were perpetrators–victims during the previous 2 months. Cyberbullying may be more insidious than traditional bullying, because cyberbullying can quickly reach wide audiences (e.g., e-mails sent to an entire school), can be perpetrated anonymously, and is not bound to in-person interactions.4,5 Although cyberbullying has garnered widespread media attention, to our knowledge, no previous study has explored correlates of cyberbullying with a representative probability sample in an urban middle-school sample.Cyberbullying is associated with a host of health and behavioral health consequences. Research has suggested that cyberbullying may have a greater effect on depression and suicidal ideation than traditional offline bullying.6 Both perpetration and victimization are associated with mental health consequences, including lower self-esteem,7 recent depressive symptoms,5,8,9 and suicidal ideation.5,8,10 Cyberbullying perpetrators are more likely to have problems with their behavior, peer relationships, and emotions, and are less likely to be prosocial than their peers who are neither cyberbullying perpetrators nor victims of cyberbullying.11 Specifically, female cyberbullying perpetrators express greater anxiety and depression than their female peers who are not cyberbullying perpetrators.12 Cyberbullying victimization is also strongly associated with substance use, violent behavior, and risky sexual behavior among high-school students.10Cyberbullying disproportionately affects youths who are already vulnerable to mental health and behavioral health disparities, including members of sexual minorities (i.e., gay, lesbian, bisexual), girls, and racial and ethnic minorities. More than half of sexual-minority middle- and high-school students nationally report being a cyberbully victim during the previous year, with almost one fifth reporting often or frequent victimization.13 Female students are significantly more likely to be cyberbully perpetrators–victims than their male peers.9,14 Studies have reported that male students are significantly more likely to be cyberbullying perpetrators2,15 and significantly less likely to be cyberbully victims.2,6,9 Middle-school boys are more likely to cyberbully others because of their race, sexual identity, or both.16 African American students are more likely to be cyberbully perpetrators and Hispanic students are more likely to be cyberbully perpetrators–victims than their White peers.2Cyberbullying may occur across a variety of technology platforms, and the specific qualities of each platform may affect how cyberbullying is perpetrated and experienced. Earlier studies suggested that instant messaging, chat rooms, and message boards were the most common mediums for middle-school students who experienced cyberbullying.3,17 More recently, youths have migrated to social media platforms such as Facebook,18–20 necessitating an examination of cyberbullying across more contemporary and emerging platforms for youth interaction.More frequent use of technology has also been associated with cyberbullying. Students who use the Internet for at least 3 hours per day and those who use instant messaging and Web cams are significantly more likely to have been cyberbully victims at least 7 times during the previous year.17 Frequent Internet users are significantly more likely to be cyberbully perpetrators, victims, and perpetrators–victims.14Research has shown that even though cyberbullying takes place in a virtual space, most cyberbullying perpetrators know their victims and vice versa. Moreover, 73% of victims reported being “pretty sure” or “totally sure” about the identity of their cyberbully, with 51% of cyberbullying perpetrators identified as a classmate, 43% as someone who they only knew online, and 20% as an in-person, nonclassmate relation.17 Cyberbullying perpetrators of middle-school victims were most often a classmate or a stranger; cyberbullying perpetrators most often reported that they cyberbullied classmates, friends, and strangers.3This study expanded previous work with high-school samples2 and nonprobability samples of middle-school students3,17 to explore the role of sexual identity, gender, race, and technology use patterns in a random sample of urban middle-school students in Los Angeles County, California. The study focused on demographic characteristics including sexual identity, patterns of technology use (i.e., frequency of Internet use, texting, parental rules regarding Internet use), and platforms on which middle-school students experience cyberbullying (i.e., Facebook, Twitter, e-mail, text messaging) to inform interventions to disrupt this maladaptive behavior and help protect early adolescents from the consequences of cyberbullying.  相似文献   
989.

Background

Lead (Pb) exposure and obesity are co-occurring risk factors for decreased bone mass in the young, particularly in low socioeconomic communities.

Objectives

The goal of this study was to determine whether the comorbidities of Pb exposure and high-fat diet–induced obesity amplify skeletal deficits independently associated with each of these risk factors, and to explore associated mechanisms of the observed deficiencies.

Methods

Five-week-old male C57BL/6J mice were placed on low-fat (10% kcal, LFD) or high-fat (60% kcal, HFD) diets for 12 weeks. Mice were exposed to lifetime Pb (50 ppm) through drinking water.

Results

HFD was associated with increased body mass and glucose intolerance. Both HFD and Pb increased fasting glucose and serum leptin levels. Pb and HFD each reduced trabecular bone quality and together had a further detrimental effect on these bone parameters. Mechanical bone properties of strength were depressed in Pb-exposed bones, but HFD had no significant effect. Both Pb and HFD altered progenitor cell differentiation, promoting osteoclastogenesis and increasing adipogenesis while suppressing osteoblastogenesis. In support of this lineage shift being mediated through altered Wnt signaling, Pb and non-esterified fatty acids in MC3T3 cells increased in vitro PPAR-γ activity and inhibited β-catenin activity. Combining Pb and non-esterified fatty acids enhanced these effects.

Conclusions

Pb and HFD produced selective deficits in bone accrual that were associated with alterations in progenitor cell activity that may involve reduced Wnt signaling. This study emphasizes the need to assess toxicants together with other risk factors relevant to human health and disease.

Citation

Beier EE, Inzana JA, Sheu TJ, Shu L, Puzas JE, Mooney RA. 2015. Effects of combined exposure to lead and high-fat diet on bone quality in juvenile male mice. Environ Health Perspect 123:935–943; http://dx.doi.org/10.1289/ehp.1408581  相似文献   
990.
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