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排序方式: 共有592条查询结果,搜索用时 31 毫秒
1.
Venkatesan Chakrapani Thilakavathi Subramanian Pandara Purayil Vijin Ruban Nelson Murali Shunmugam Trace Kershaw 《Global public health》2020,15(3):438-451
ABSTRACTHIV-positive men who have sex with men (HIV+MSM) in India need culturally-relevant interventions to promote safer sex. We tested a multi-level intervention among HIV+MSM that targeted individual, interpersonal, and community factors, based on the Social-Personal and Social Ecological Models. We conducted a 2?×?2 factorial RCT with 119 HIV+MSM randomised to receive either an individual-level intervention (ILI) using motivational interviewing to promote safer sex, a community-level intervention (CLI) to strengthen community norms toward safer sex and reduce stigma among MSM communities, a multi-level intervention combining the individual- and community-level interventions (ILI?+?CLI), or standard-of-care control. Participants completed pre- and post-intervention assessments of a composite sexual risk score and a process evaluation to assess fidelity and satisfaction. Out of the 119 HIV+MSM, 106 (89.0%) completed pre- and post-intervention assessments. Generalised Estimating Equation models showed that both CLI (Incidence Rate Ratio [IRR]?=?.67, 95% CI .47 to .96) and ILI?+?CLI (IRR?=?.66, 95% CI .48 to .91) groups had a statistically significant decrease in sexual risk compared to the standard-of-care. The interventions had high levels of fidelity and satisfaction. This pilot RCT demonstrated feasibility and potential effectiveness of a multi-level intervention that addresses individual, interpersonal and community-level contributors of sexual risk among HIV+MSM. 相似文献
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W C Kershaw L D Lehman-McKeeman C D Klaassen 《Toxicology and applied pharmacology》1990,104(2):267-275
The purpose of this study was to quantitate hepatic metallothionein-I (MT-I) and metallothionein-II (MT-II) in adult mice pretreated with various dosages of selected inorganic and organic compounds and in nonchemically treated neonatal mice. Male CF-1 mice received Zn (0.38-6.0 mmol/kg, sc), Cd (5-80 mumol/kg, sc), dexamethasone (10-1000 mumol/kg, sc), or ethanol (60-180 mmol/kg, po). Liver cytosol was prepared 24 hr after the administration of each compound. In another experiment, liver cytosols were prepared from male and female neonates 1 to 35 days after parturition. MT-I and MT-II in liver cytosols were isolated by high-performance anion-exchange chromatography and quantitated by atomic absorption spectrometry. Hepatic MT-I and MT-II concentrations in adult controls were 5.1 +/- 1.3 and 3.7 +/- 1.0 micrograms/g liver, respectively. All compounds increased hepatic MT levels in a dose-dependent manner over a narrow range of dosages. The lowest dosages of Zn, Cd, dexamethasone, and ethanol that produced a significant increase in total MT content (MT-I plus MT-II) were 0.38, 0.005, 0.3, and 90 mmol/kg, respectively. Maximal induction of total MT following the highest dosages of Zn, Cd, ethanol, and dexamethasone was 58, 34, 24, and 13 times the control value (8.8 +/- 2.4 micrograms total MT/g liver), respectively. The relationship between dose and hepatic MT content was linear following ethanol administration and log-linear following Zn, Cd, and dexamethasone administration. The ratio of MT-I/MT-II was approximately 2.4 following all dosages of metals. Following low and high dosages of organic compounds, the ratio of MT-I/MT-II was approximately 1.0 and 1.5, respectively. Total MT concentration in livers of 1- to 14-day-old mice was approximately 40 times that observed in adult liver (5.5 +/- 1.6 micrograms total MT/g liver) and returned toward adult levels 21 days after parturition. The ratio of MT-I/MT-II was approximately 1.8 during Postpartum Days 1 through 14 and thereafter decreased to approximately 1.0. These results indicate that MT-I is more abundant than MT-II in mouse liver following chemical exposure and during neonatal development. 相似文献
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Liefeldt L Plentz A Klempa B Kershaw O Endres AS Raab U Neumayer HH Meisel H Modrow S 《Journal of medical virology》2005,75(1):161-169
Organ transplant recipients infected with parvovirus B19 frequently develop persistent viremia associated with chronic anemia and pure red cell aplasia. In this study, a male renal transplant recipient who had been infected with parvovirus B19/genotype 2 after renal transplantation at the age of 34 years is described. The patient was repeatedly treated with high dose intravenous immunoglobulin (IVIG) that resulted in the resolvement of symptoms but not in virus eradication. During an observation period of 33 months after transplantation three phases associated with high parvovirus B19 viremia were observed. Both the first and the second viremic phases were combined with severe anemia. Parvovirus B19 specific IgM-antibodies were initially detected at the beginning of the second phase in continually rising concentrations. Initially eradication of the virus by immunoglobulin therapy was reported after the first viremic phase [Liefeldt et al. (2002): Nephrol Dial Transplant 17:1840-1842]. Retrospectively this statement has to be corrected. It was based on the use of a qualitative PCR assay specific for parvovirus B19 genotype 1 associated with reduced sensitivity for detection of genotype 2. After sequence analysis of the viral DNA and adjustment of a real-time PCR assay (TaqMan) for quantitative detection of all three B19 virus genotypes analysis of consecutive serum samples allowed the demonstration of long lasting phases with reduced viral loads following IVIG-treatment. These results demonstrate that IVIG treatment of parvovirus B19-triggered anemia in transplant recipients offers an opportunity to resolve symptoms, but does not guarantee eradication of the virus. Since reactivation of parvovirus B19 infection can result in high virus load associated with the recurrence of symptoms repeated screening for viral DNA is recommended using the TaqMan system established for quantitative detection of all three genotypes of parvovirus B19. 相似文献
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Charles Varnell Jr Lyndsay A. Harshman Laurie Smith Chunyan Liu Shiran Chen Samhar Al-Akash Gina-Marie Barletta Craig Belsha Paul Brakeman Abanti Chaudhuri Paul Fadakar Rouba Garro Caroline Gluck Jens Goebel David Kershaw Debora Matossian Corina Nailescu Hiren P. Patel Cozumel Pruette Saritha Ranabothu Nancy Rodig Jodi Smith Judith Sebestyen VanSickle Patricia Weng Lara Danziger-Isakov David K. Hooper Michael Seifert 《American journal of transplantation》2021,21(8):2740-2748
There are limited data on the impact of COVID-19 in children with a kidney transplant (KT). We conducted a prospective cohort study through the Improving Renal Outcomes Collaborative (IROC) to collect clinical outcome data about COVID-19 in pediatric KT patients. Twenty-two IROC centers that care for 2732 patients submitted testing and outcomes data for 281 patients tested for SARS-CoV-2 by PCR. Testing indications included symptoms and/or potential exposures to COVID-19 (N = 134, 47.7%) and/or testing per hospital policy (N = 154, 54.8%). Overall, 24 (8.5%) patients tested positive, of which 15 (63%) were symptomatic. Of the COVID-19-positive patients, 16 were managed as outpatients, six received non-ICU inpatient care and two were admitted to the ICU. There were no episodes of respiratory failure, allograft loss, or death associated with COVID-19. To estimate incidence, subanalysis was performed for 13 centers that care for 1686 patients that submitted all negative and positive COVID-19 results. Of the 229 tested patients at these 13 centers, 10 (5 asymptomatic) patients tested positive, yielding an overall incidence of 0.6% and an incidence among tested patients of 4.4%. Pediatric KT patients in the United States had a low estimated incidence of COVID-19 disease and excellent short-term outcomes. 相似文献
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This study examined the influence of parental, school, and peer bonding for rural youth making the transition into middle school. Survey data were collected from 225 adolescents and their mothers answering parallel items on family cohesion, school attachment, and attitudes toward substance use by minors. Adolescents also reported on social support from friends, and mothers reported on the family's involvement in religious activities. Using structural equation modeling, greater family cohesion at the start of middle school / junior high was directly and indirectly related to negative attitudes toward substance use by the adolescent one year later. Factors that mediated family cohesion were school and peer attachment, the family's involvement in religious activities, and the mothers' attitudes toward substance use by minors. Implications for prevention and recommendations for parents are discussed. 相似文献
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Sarah K. Calabrese Valerie A. Earnshaw Douglas S. Krakower Kristen Underhill Wilson Vincent Manya Magnus Nathan B. Hansen Trace S. Kershaw Kenneth H. Mayer Joseph R. Betancourt John F. Dovidio 《AIDS and behavior》2018,22(4):1122-1138
Social biases among healthcare providers could limit PrEP access. In this survey study of 115 US medical students, we examined associations between biases (racism and heterosexism) and PrEP clinical decision-making and explored prior PrEP education as a potential buffer. After viewing a vignette about a PrEP-seeking MSM patient, participants reported anticipated patient behavior (condomless sex, extra-relational sex, and adherence), intention to prescribe PrEP to the patient, biases, and background characteristics. Minimal evidence for racism affecting clinical decision-making emerged. In unadjusted analyses, heterosexism indirectly affected prescribing intention via all anticipated behaviors, tested as parallel mediators. Participants expressing greater heterosexism more strongly anticipated increased risk behavior and adherence problems, which were associated with lower prescribing intention. The indirect effect via condomless sex remained significant adjusting for background characteristics. Prior PrEP education did not buffer any indirect effects. Heterosexism may compromise PrEP provision to MSM and should be addressed in PrEP-related medical education. 相似文献