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2.
Glob Public Health ; 13(2): 144-158, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27169632

RESUMEN

The House Ball Community (HBC) is an understudied network of African American men who have sex with men and transgender women, who join family-like houses that compete in elaborate balls in cities across the United States. From 2011 to 2012, we surveyed 274 recent attendees of balls in the San Francisco Bay Area, focusing on social networks, social support, and HIV-related behaviours. Participants with a high percentage of alters who were supportive of HIV testing were significantly more likely to have tested in the past six months (p = .02), and less likely to have engaged in unprotected anal intercourse (UAI) in the past three months (p = .003). Multivariate regression analyses of social network characteristics, and social support, revealed that testing in the past six months was significantly associated with social support for safer sex, instrumental social support, and age. Similarly, UAI in the past three months was significantly associated with social support for safer sex, homophily based on sexual identity and HIV status. HIV-related social support provided through the HBC networks was correlated with recent HIV testing and reduced UAI. Approaches utilising networks within alternative kinship systems, may increase HIV-related social support and improve HIV-related outcomes.


Asunto(s)
Negro o Afroamericano/psicología , Infecciones por VIH/etnología , Homosexualidad Masculina/etnología , Apoyo Social , Personas Transgénero/psicología , Adolescente , Adulto , Negro o Afroamericano/estadística & datos numéricos , Estudios Transversales , Femenino , Infecciones por VIH/prevención & control , Homosexualidad Masculina/psicología , Homosexualidad Masculina/estadística & datos numéricos , Humanos , Masculino , Tamizaje Masivo/estadística & datos numéricos , Personas Transgénero/estadística & datos numéricos , Estados Unidos/epidemiología , Sexo Inseguro/etnología , Sexo Inseguro/estadística & datos numéricos , Adulto Joven
3.
AIDS Behav ; 21(10): 2924-2934, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28097618

RESUMEN

HIV prevention programs often focus on the physical social venues where men who have sex with men (MSM) frequent as sites where sex behaviors are assumed to be practiced and risk is conferred. But, how exactly these behaviors influence venue patronage is not well understood. In this study, we present a two-mode network analysis that determines the extent that three types of sex behaviors-condomless sex, sex-drug use, and group sex-influence the patronage of different types of social venues among a population sample of young Black MSM (YBMSM) (N = 623). A network analytic technique called exponential random graph modeling was used in a proof of concept analysis to verify how each sex behavior increases the likelihood of a venue patronage tie when estimated as either: (1) an attribute of an individual only and/or (2) a shared attribute between an individual and his peers. Findings reveal that sex behaviors, when modeled only as attributes possessed by focal individuals, were no more or less likely to affect choices to visit social venues. However, when the sex behaviors of peers were also taken into consideration, we learn that individuals were statistically more likely in all three behavioral conditions to go places that attracted other MSM who practiced the same behaviors. This demonstrates that social venues can function as intermediary contexts in which relationships can form between individuals that have greater risk potential given the venues attraction to people who share the same risk tendencies. As such, structuring interventions around these settings can be an effective way to capture the attention of YBMSM and engage them in HIV prevention.


Asunto(s)
Negro o Afroamericano/psicología , Señales (Psicología) , Infecciones por VIH/prevención & control , Homosexualidad Masculina/psicología , Conducta Sexual/psicología , Red Social , Trastornos Relacionados con Sustancias/psicología , Sexo Inseguro/estadística & datos numéricos , Adolescente , Adulto , Homosexualidad Masculina/etnología , Homosexualidad Masculina/estadística & datos numéricos , Humanos , Masculino , Motivación , Asunción de Riesgos , Conducta Sexual/estadística & datos numéricos , Trastornos Relacionados con Sustancias/epidemiología , Sexo Inseguro/psicología , Adulto Joven
4.
Soc Sci Med ; 174: 26-34, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27987435

RESUMEN

The endogenous social support systems of young Black men who have sex with men (YBMSM), like surrogate families and social networks, are considered crucial assets for HIV prevention in this population. Yet, the extent to which these social systems foster sexual health protections or risks remains unclear. We examine the networked patterns of membership in ballroom houses and independent gay families, both Black gay subcultures in the United States, and how these memberships are related to HIV protective and risk traits of members. Drawing from a population-based sample of 618 YBMSM living in Chicago between June 2013 and July 2014, we observe a suite of protective and risk traits and perform bivariate analyses to assess each of their associations with being a member of a house or family. We then present an analysis of the homophilous and heterophilous mixing on these traits that structures the patterns of house and family affiliations among members. The bivariate analyses show that members of the house and family communities were more likely than non-members to report protective traits like being aware of PrEP, having health coverage, having a primary care doctor, and discouraging sex drug use among peers. However, members were also more likely to engage in the use of sex drugs. With respect to how these traits inform specific house/family affiliations, results show that members who had a recent HIV test, who were PrEP aware, or who engaged in exchange sex were more likely to belong to the same house or family, while HIV positive individuals were less likely to cluster within houses or families. These findings provide insights regarding the strengths and vulnerabilities of the house and gay family communities that can inform more culturally specific interventions that build on the existing human and social capital in this milieu.


Asunto(s)
Infecciones por VIH/prevención & control , Homosexualidad Masculina/psicología , Conducta Sexual/psicología , Minorías Sexuales y de Género/psicología , Adolescente , Adulto , Negro o Afroamericano/etnología , Negro o Afroamericano/psicología , Negro o Afroamericano/estadística & datos numéricos , Chicago/etnología , Estudios de Cohortes , Familia/etnología , Familia/psicología , Infecciones por VIH/etnología , Homosexualidad Masculina/estadística & datos numéricos , Humanos , Masculino , Factores de Riesgo , Asunción de Riesgos , Conducta Sexual/estadística & datos numéricos , Minorías Sexuales y de Género/estadística & datos numéricos , Red Social
5.
Water Res ; 104: 473-484, 2016 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-27585427

RESUMEN

Bioassays are particularly useful tools to link the chemical and ecological assessments in water quality monitoring. Different methods cover a broad range of toxicity mechanisms in diverse organisms, and account for risks posed by non-target compounds and mixtures. Many tests are already applied in chemical and waste assessments, and stakeholders from the science-police interface have recommended their integration in regulatory water quality monitoring. Still, there is a need to address bioassay suitability to evaluate water samples containing emerging pollutants, which are a current priority in water quality monitoring. The presented interlaboratory study (ILS) verified whether a battery of miniaturized bioassays, conducted in 11 different laboratories following their own protocols, would produce comparable results when applied to evaluate blinded samples consisting of a pristine water extract spiked with four emerging pollutants as single chemicals or mixtures, i.e. triclosan, acridine, 17α-ethinylestradiol (EE2) and 3-nitrobenzanthrone (3-NBA). Assays evaluated effects on aquatic organisms from three different trophic levels (algae, daphnids, zebrafish embryos) and mechanism-specific effects using in vitro estrogenicity (ER-Luc, YES) and mutagenicity (Ames fluctuation) assays. The test battery presented complementary sensitivity and specificity to evaluate the different blinded water extract spikes. Aquatic organisms differed in terms of sensitivity to triclosan (algae > daphnids > fish) and acridine (fish > daphnids > algae) spikes, confirming the complementary role of the three taxa for water quality assessment. Estrogenicity and mutagenicity assays identified with high precision the respective mechanism-specific effects of spikes even when non-specific toxicity occurred in mixture. For estrogenicity, although differences were observed between assays and models, EE2 spike relative induction EC50 values were comparable to the literature, and E2/EE2 equivalency factors reliably reflected the sample content. In the Ames, strong revertant induction occurred following 3-NBA spike incubation with the TA98 strain, which was of lower magnitude after metabolic transformation and when compared to TA100. Differences in experimental protocols, model organisms, and data analysis can be sources of variation, indicating that respective harmonized standard procedures should be followed when implementing bioassays in water monitoring. Together with other ongoing activities for the validation of a basic bioassay battery, the present study is an important step towards the implementation of bioanalytical monitoring tools in water quality assessment and monitoring.


Asunto(s)
Calidad del Agua , Agua , Animales , Bioensayo , Monitoreo del Ambiente , Contaminantes Químicos del Agua , Purificación del Agua
6.
Artículo en Inglés | MEDLINE | ID: mdl-26905402

RESUMEN

Social networks influence health behavior and health status. Within social networks, "key players" often influence those around them, particularly in traditionally underserved areas like the Appalachian region in the USA. From a total sample of 787 Appalachian residents, we identified and interviewed 10 key players in complex networks, asking them what comprises a key player, their role in their network and community, and ideas to overcome and increase colorectal cancer (CRC) screening. Key players emphasized their communication skills, resourcefulness, and special occupational and educational status in the community. Barriers to CRC screening included negative perceptions of the colonoscopy screening procedure, discomfort with the medical system, and misinformed perspectives on screening. Ideas to improve screening focused on increasing awareness of women's susceptibility to CRC, providing information on different screening tests, improving access, and the key role of health-care providers and key players themselves. We provide recommendations to leverage these vital community resources.


Asunto(s)
Colonoscopía/estadística & datos numéricos , Neoplasias Colorrectales/prevención & control , Conocimientos, Actitudes y Práctica en Salud , Pobreza , Población Rural/estadística & datos numéricos , Apoyo Social , Región de los Apalaches , Neoplasias Colorrectales/diagnóstico , Detección Precoz del Cáncer/estadística & datos numéricos , Femenino , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Humanos , Entrevistas como Asunto , Kentucky , Masculino , Tamizaje Masivo/estadística & datos numéricos , Persona de Mediana Edad , Ohio , Aceptación de la Atención de Salud/estadística & datos numéricos
7.
Chemosphere ; 120: 321-7, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25170595

RESUMEN

Cyanobacteria contain various types of bioactive compounds, which could cause adverse effects on organisms. They are released into surface waters during cyanobacterial blooms, but there is little information on their potential relevance for effects in vivo. In this study presence of bioactive compounds was characterized in cyanobacteria Microcystis aeruginosa (Chroococcales), Planktothrix agardhii (Oscillatoriales) and Aphanizomenon gracile (Nostocales) with selected in vitro assays. The in vivo relevance of detected bioactivities was analysed using transgenic zebrafish embryos tg(cyp19a1b-GFP). Teratogenic potency was assessed by analysis of developmental disorders and effects on functions of the neuromuscular system by video tracking of locomotion. Estrogenicity in vitro corresponded to 0.95-54.6 ng estradiol equivalent(g dry weight (dw))(-1). In zebrafish embryos, estrogenic effects could not be detected potentially because they were masked by high toxicity. There was no detectable (anti)androgenic/glucocorticoid activity in any sample. Retinoid-like activity was determined at 1-1.3 µg all-trans-retinoic acid equivalent(g dw)(-1). Corresponding to the retinoid-like activity A. gracile extract also caused teratogenic effects in zebrafish embryos. Furthermore, exposure to biomass extracts at 0.3 gd wL(-1) caused increase of body length in embryos. There were minor effects on locomotion caused by 0.3 gd wL(-1)M. aeruginosa and P. agardhii extracts. The traditionally measured cyanotoxins microcystins did not seem to play significant role in observed effects. This indicates importance of other cyanobacterial compounds at least towards some species or their developmental phases. More attention should be paid to activity of retinoids, estrogens and other bioactive substances in phytoplankton using in vitro and in vivo bioassays.


Asunto(s)
Cianobacterias/química , Disruptores Endocrinos/toxicidad , Neurotoxinas/toxicidad , Teratógenos/toxicidad , Pez Cebra/metabolismo , Animales , Animales Modificados Genéticamente/embriología , Animales Modificados Genéticamente/genética , Animales Modificados Genéticamente/metabolismo , Aphanizomenon/química , Bioensayo , Embrión no Mamífero/efectos de los fármacos , Microcystis/química , Pez Cebra/embriología , Pez Cebra/genética
8.
Aquat Toxicol ; 155: 283-90, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25103898

RESUMEN

Retinoic acids and their derivatives have been recently identified by chemical analyses in cyanobacteria and algae. Given the essential role of retinoids for vertebrate development this has raised concerns about a potential risk for vertebrates exposed to retinoids during cyanobacterial blooms. Our study focuses on extracellular compounds produced by phytoplankton cells (exudates). In order to address the capacity for the production of retinoids or compounds with retinoid-like activity we compared the exudates of ten cyanobacteria and algae using in vitro reporter gene assay. Exudates of three cyanobacterial species showed retinoid-like activity in the range of 269-2,265 ng retinoid equivalents (REQ)/L, while there was no detectable activity in exudates of the investigated algal species. The exudates of one green alga (Desmodesmus quadricaudus) and the two cyanobacterial species with greatest REQ levels, Microcystis aeruginosa and Cylindrospermopsis raciborskii, were selected for testing of the potential relation of retinoid-like activity to developmental toxicity in zebrafish embryos. The exudates of both cyanobacteria were indeed provoking diverse teratogenic effects (e.g. tail, spine and mouth deformation) and interference with growth in zebrafish embryos, while such effects were not observed for the alga. Fish embryos were also exposed to all-trans retinoic acid (ATRA) in a range equivalent to the REQ concentrations detected in exudates by in vitro bioassays. Both the phenotypes and effective concentrations of exudates corresponded to ATRA equivalents, supporting the hypothesis that the teratogenic effects of cyanobacterial exudates are likely to be associated with retinoid-like activity. The study documents that some cyanobacteria are able to produce and release retinoid-like compounds into the environment at concentrations equivalent to those causing teratogenicity in zebrafish. Hence, the characterization of retinoid-like and teratogenic potency should be included in the assessment of the potential adverse effects caused by the release of toxic and bioactive compounds during cyanobacterial blooms.


Asunto(s)
Chlorophyta/metabolismo , Cylindrospermopsis/metabolismo , Microcystis/metabolismo , Retinoides/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Bioensayo , Regulación del Desarrollo de la Expresión Génica , Genes Reporteros , Retinoides/química , Retinoides/metabolismo , Teratógenos , Tretinoina/toxicidad , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/metabolismo , Pez Cebra/embriología
9.
Toxicol Sci ; 141(1): 218-33, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24958932

RESUMEN

The risk posed by complex chemical mixtures in the environment to wildlife and humans is increasingly debated, but has been rarely tested under environmentally relevant scenarios. To address this issue, two mixtures of 14 or 19 substances of concern (pesticides, pharmaceuticals, heavy metals, polyaromatic hydrocarbons, a surfactant, and a plasticizer), each present at its safety limit concentration imposed by the European legislation, were prepared and tested for their toxic effects. The effects of the mixtures were assessed in 35 bioassays, based on 11 organisms representing different trophic levels. A consortium of 16 laboratories was involved in performing the bioassays. The mixtures elicited quantifiable toxic effects on some of the test systems employed, including i) changes in marine microbial composition, ii) microalgae toxicity, iii) immobilization in the crustacean Daphnia magna, iv) fish embryo toxicity, v) impaired frog embryo development, and vi) increased expression on oxidative stress-linked reporter genes. Estrogenic activity close to regulatory safety limit concentrations was uncovered by receptor-binding assays. The results highlight the need of precautionary actions on the assessment of chemical mixtures even in cases where individual toxicants are present at seemingly harmless concentrations.


Asunto(s)
Bioensayo/métodos , Conservación de los Recursos Naturales/legislación & jurisprudencia , Monitoreo del Ambiente , Pruebas de Toxicidad/métodos , Contaminantes Químicos del Agua/toxicidad , Animales , Monitoreo del Ambiente/legislación & jurisprudencia , Monitoreo del Ambiente/métodos , Unión Europea , Regulación Gubernamental , Humanos , Contaminantes Químicos del Agua/química
10.
Environ Sci Pollut Res Int ; 21(17): 10419-31, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24838126

RESUMEN

Organobromines of natural and artificial origin are omnipresent in aquatic and terrestrial environments. Although it is well established that exposure to high concentrations of organobromines are harmful to vertebrates, few studies have investigated the effect of environmentally realistic concentrations on invertebrates. Here, the nematode Caenorhabditis elegans was challenged with two organobromines, namely dibromoacetic acid (DBAA) and tetrabromobisphenol-A (TBBP), and monitored for changes in different life trait variables and global gene expression patterns. Fifty micromolar DBAA stimulated the growth and lifespan of the nematodes; however, the onset of reproduction was delayed. In contrast, TBBP changed the lifespan in a hormetic fashion, namely it was stimulated at 0.1 µM but impaired at 50 µM. The reproductive performance was even impaired at 2 µM TBBP. Moreover, DBAA could not reduce the toxic effect of TBBP when applied as a mixture. A whole-genome DNA microarray revealed that both organobromines curtailed signalling and neurological processes. Furthermore on the transcription level, 50 µM TBBP induced proteolysis and DBAA up-regulated biosynthesis and metabolism. To conclude, even naturally occurring concentrations of organobromines can influence the biomolecular responses and life cycle traits in C. elegans. The life extension is accompanied by negative changes in the reproductive behaviour, which is crucial for the stability of populations. Thus, this paper highlights that the effects of exposure to moderate, environmentally realistic concentrations of organobromines should not be ignored.


Asunto(s)
Acetatos/toxicidad , Caenorhabditis elegans/efectos de los fármacos , Expresión Génica/efectos de los fármacos , Bifenilos Polibrominados/toxicidad , Reproducción/efectos de los fármacos , Animales , Caenorhabditis elegans/crecimiento & desarrollo , Hormesis/efectos de los fármacos
11.
Soc Sci Med ; 74(10): 1602-9, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22465379

RESUMEN

Studies have shown that position within networks of social relations can have direct implications on the health behaviors of individuals. The present study examines connections between drug use and individual social capital within social networks of drug users (n = 503) from rural Appalachian Kentucky, U.S.A. Respondent driven sampling was used to recruit individuals age 18 and older who had used one of the following drugs to get high: cocaine, crack, heroin, methamphetamine, or prescription opioids. Substance use was measured via self-report and social network analysis of participants' drug use network was used to compute effective size, a measure of social capital. Drug network ties were based on sociometric data on recent (past 6 month) drug co-usage. Multivariate multi-level ordinal regression was used to model the independent effect of socio-demographic and drug use characteristics on social capital. Adjusting for gender, income, and education, daily OxyContin(®) use was found to be significantly associated with greater social capital, and daily marijuana use was associated with less social capital. These results suggest that in regions with marked economic disparities such as rural Appalachia, OxyContin(®) may serve as a form of currency that is associated with increased social capital among drug users. Interventions focusing on increasing alternate pathways to acquiring social capital may be one way in which to alleviate the burden of drug use in this high-risk population.


Asunto(s)
Consumidores de Drogas/psicología , Drogas Ilícitas , Apoyo Social , Trastornos Relacionados con Sustancias/psicología , Adulto , Analgésicos Opioides , Consumidores de Drogas/estadística & datos numéricos , Femenino , Humanos , Hidrocodona , Relaciones Interpersonales , Kentucky/epidemiología , Masculino , Análisis Multinivel , Trastornos Relacionados con Opioides/epidemiología , Trastornos Relacionados con Opioides/psicología , Oxicodona , Población Rural/estadística & datos numéricos , Distribución por Sexo , Factores Socioeconómicos , Trastornos Relacionados con Sustancias/epidemiología
12.
Am J Med Genet A ; 152A(5): 1264-7, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20425833

RESUMEN

Hereditary multiple exostosis (HME) is an autosomal dominant disorder characterized by multiple osteochondromas. We describe a case of acute cervical spinal cord compression arising from an exostosis at the lamina of C7 and T1 in a 4-year-old Mexican-American boy with HME. His affected sibling also displayed spinal cord compression because of a bony exostosis. Acute cervical spinal cord compression resulting from osteochondroma is a serious complication of HME. (c) 2010 Wiley-Liss, Inc.


Asunto(s)
Exostosis Múltiple Hereditaria/diagnóstico , Columna Vertebral/anomalías , Preescolar , Exostosis Múltiple Hereditaria/diagnóstico por imagen , Femenino , Humanos , Recién Nacido , Imagen por Resonancia Magnética , Masculino , Embarazo , Columna Vertebral/diagnóstico por imagen , Tomografía Computarizada por Rayos X
13.
J Pediatr ; 155(6): 924-7, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19914430

RESUMEN

A symptom-free woman gave birth to a girl with a low carnitine level on newborn screening. The baby was unaffected, but the mother had biochemical abnormalities and mutations characteristic of the cblC defect of vitamin B(12) metabolism (late-onset form). This patient with cblC was detected through her infant's newborn screening.


Asunto(s)
Carnitina/metabolismo , Homocistinuria/diagnóstico , Tamizaje Neonatal , Trastornos Puerperales/diagnóstico , Adulto , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Femenino , Homocistinuria/genética , Homocistinuria/metabolismo , Humanos , Recién Nacido , Oxidorreductasas , Trastornos Puerperales/genética , Trastornos Puerperales/metabolismo
14.
Am J Med Genet A ; 130A(4): 402-5, 2004 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-15384101

RESUMEN

A 3-month-old boy with Costello syndrome (CS) developed respiratory distress and fatal arrhythmias. An autopsy showed cardiac hypertrophy, mild coarctation of the aorta, and pancreatic islet cell hyperplasia. To our knowledge, this is the first report of a pancreatic abnormality in CS. Islet cell hyperplasia has also been observed in leprechaunism, Beckwith-Wiedemann (BWS), and Simpson-Golabi-Behmel syndromes. The syndromes are thought to involve abnormal insulin or insulin-like growth factor (IGF) pathways. Clinical similarities among these disorders and CS, together with the finding of islet cell hyperplasia, suggest that they may be related.


Asunto(s)
Trastornos del Crecimiento/genética , Islotes Pancreáticos/patología , Anomalías Múltiples/genética , Aorta/anomalías , Autopsia , Cardiomegalia/genética , Humanos , Hiperplasia , Lactante , Masculino , Síndrome
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