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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
2.
Brain neurons and glial cells express Neu differentiation factor/heregulin: a survival factor for astrocytes. 总被引:8,自引:1,他引:7
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R Pinkas-Kramarski R Eilam O Spiegler S Lavi N Liu D Chang D Wen M Schwartz Y Yarden 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(20):9387-9391
Neu differentiation factor (NDF, also called heregulin) was isolated from mesenchymal cells on the basis of its ability to elevate phosphorylation of ErbB proteins. Earlier in situ hybridization analysis showed that NDF was transcribed predominantly in the central nervous system during embryonic development. To gain insights into the role of NDF in brain we analyzed its distribution by immunohistochemistry and in situ hybridization. Late-gestation (day 17) rat embryos displayed high NDF immunoreactivity in both motor (e.g., putamen) and limbic (e.g., septum) regions. Lower levels of the factor were exhibited by adult brain, except for the cerebellum, where NDF expression was increased postnatally. Both neurons and glial cells were identified by immunohistochemistry as NDF-producing cells (e.g., pyramidal neurons in the cerebral cortex and glial cells in the corpus callosum). By establishment of primary cultures of rat brain cells we confirmed that NDF was expressed in neurons as well as in astrocytes. In addition, by using such primary cultures we observed that NDF treatment exerted only a limited mitogenic effect, which was accompanied by significant acceleration of astrocyte maturation. Furthermore, long-term incubation with the factor specifically protected astrocytes from apoptosis, implying that NDF functions in brain as a survival and maturation factor for astrocytes. 相似文献
3.
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
4.
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
5.
Monoclonal antibodies against receptor for epidermal growth factor induce early and delayed effects of epidermal growth factor. 总被引:18,自引:7,他引:18
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A B Schreiber I Lax Y Yarden Z Eshhar J Schlessinger 《Proceedings of the National Academy of Sciences of the United States of America》1981,78(12):7535-7539
Mice were immunized with human epidermoid carcinoma cells (A-431 cell line) that possess an unusually high number of membrane receptors for epidermal growth factor (EGF). Spleen cells from these mice were fused with NSI cells, a nonsecreting murine myeloma. The immunoglobulins secreted by the obtained hybridomas were screened for specific binding to A-431 cells and selected according to their ability to inhibit the binding of radiolabeled EGF to the membrane of A-431 cells. Several antibodies secreted by cloned hybrid lines were found to inhibit the binding of radiolabeled EGF to membrane receptors of living A-431 cells, human foreskin fibroblasts, and mouse 3T3 fibroblasts and also to membrane preparations from A-431 cells. These monoclonal antibodies induced the early and delayed biological effects mediated by EGF. Like EGF, the antibodies induced morphological changes in A-431 cells and enhanced the phosphorylation of endogenous membrane proteins in membranes from these cells. They also stimulated DNA synthesis in human foreskin fibroblasts. These observations support the notion that the biological information of the EGF-receptor complex resides in the membrane receptor. Furthermore, the antibodies offer a powerful tool to study the structure, processing, and mode of action of EGF receptors. 相似文献
6.
Calabrese Sarah K. Kalwicz David A. Modrakovic Djordje Earnshaw Valerie A. Edelman E. Jennifer Bunting Samuel R. del Río-González Ana María Magnus Manya Mayer Kenneth H. Hansen Nathan B. Kershaw Trace S. Rosenberger Joshua G. Krakower Douglas S. Dovidio John F. 《AIDS and behavior》2022,26(5):1393-1421
AIDS and Behavior - Social biases may influence providers’ judgments related to pre-exposure prophylaxis (PrEP) and patients’ consequent PrEP access. US primary and HIV care providers... 相似文献
7.
The prevention of mother-to-child HIV transmission (PMTCT) is a complex challenge in heavily affected and resource-limited settings such as South Africa. Management of PMTCT requires a cascade of interventions that need to be addressed to effectively decrease the risk of HIV transmission to infants. This PMTCT cascade includes incremental components that can be shaped and influenced by the patient-provider relationship. The relationship that a pregnant woman has with her care providers may possibly affect decisions that she makes concerning her antenatal care and may, in turn, influence the quality of the care provided. A patient-provider relationship scale (PPRS) was developed in Pretoria, South Africa with two aims: first, to quantify the patient-provider relationship in an antenatal population in a resource-limited setting and provide preliminary evidence of its reliability and validity; and second, to determine whether the patient-provider relationship has an effect on PMTCT. The instrument was administrated in a cross-sectional pilot study to a group of women at discharge after delivery (n=192) at two major hospitals in South West Tshwane. Statistical analysis of the instrument showed high reliability (α=0.91) and preliminary evidence of its validity including significant associations with participants' attitudes regarding the functioning of the clinics and a single statement (the clinic staff "know me as a person," R=0.47, p<0.001) that has been shown previously to have a significant association with adherence to antiretroviral treatment. For HIV-positive participants, the PPRS was significantly associated with statements related to important components of the PMTCT cascade. In addition, those with substantially inadequate antenatal care (≤2 visits) and those who did not initiate highly active antiretroviral therapy, although eligible, had significantly poorer PPRS scores. The PPRS is a potentially useful, context-appropriate instrument that could have an important role in future research focused on improving PMTCT and decreasing the risk of HIV infection in children. 相似文献
8.
Few studies examine how relationship factors influence sexual risk. We investigated gender differences of the influence of relationship functioning on sexual risk behavior and sexually transmitted infections (STIs) among 296 young pregnant couples. Compared to women, men were twice as likely to have a concurrent partner, were less likely to intend to be monogamous in the future, had less HIV/STI knowledge and more perceived risk for HIV/STI, negative attitudes and efficacy toward condom use (all P < 0.05). For men, poor relationship functioning related to less intentions to be monogamous, more partner concurrency, worse sexual communication, and more condom use. For women, poor relationship functioning related to worse sexual communication and less condom use. In addition, women who had good relationship functioning and women who had partners with poor relationship functioning were more likely to have an STI. These results demonstrate the need to include heterosexual men and relationship factors in HIV prevention. 相似文献
9.
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