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1.
AIDS Behav ; 26(5): 1467-1476, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34982320

RESUMO

The goal of this paper is to determine the association between traveling to engage in sex work in another country and recent access to HIV testing among substance-using female sex workers (FSWs) in the Mexico-Guatemala border region. From 2012 to 2015, through modified time-location sampling and peer referral, 255 FSWs were recruited at Mexico's southern border. Participants completed questionnaires on sociodemographics, migration and mobility experiences, work environment factors, and substance use. A conceptual framework, as depicted by a directed acyclic graph (DAG), guided our analysis. Crude and adjusted logistic regression models were used to evaluate the relationships between mobility experiences and HIV testing in the past year. Overall HIV testing was low (41%); after considering relevant covariates (i.e., interaction with health services and organizations, and sex work characteristics) traveling to engage in sex work in another country was found to be positively associated with HIV testing in the past year. Future efforts need to consider voluntary and non-stigmatizing prevention HIV services and focus on reaching out to less mobile women.


RESUMEN: El objetivo de este artículo es determinar la asociación entre viajar a otro país para ejercer el comercio sexual y el acceso a una prueba reciente de VIH, en una población de mujeres trabajadoras sexuales en la frontera de México con Guatemala. Entre el 2012 y 2015, utilizando un muestreo por conveniencia y por referencia de pares, se invitó a 255 mujeres trabajadoras sexuales en la frontera sur de México a participar en este proyecto de investigación. Las participantes completaron una encuesta que comprendió preguntas sociodemográficas así como experiencias de migración y movilidad, características del trabajo sexual, y patrones de uso de sustancia. Utilizamos un marco conceptual que se ilustra en una Gráfica Acíclica Dirigida (DAG) el cual sirvió para guiar nuestro análisis. Realizamos análisis de regresión logística cruda y ajustada para evaluar la asociación entre experiencias de movilidad y haber recibido una prueba de VIH en el último año. En general, el porcentaje de haber recibido una prueba de VIH en el último año fue bajo (41%); después de considerar covariables relevantes; (ej., interacción con organizaciones y servicios de salud, características del trabajo sexual) encontramos que viajar a otro país para ejercer el comercio sexual está asociado con haber recibido una prueba de VIH en el último año. Es importante que, en el futuro, se concentren esfuerzos en servicios de prevención del VIH que sean voluntarios, no estigmatizantes, y que se enfoquen en mujeres trabajadoras sexuales menos móviles.


Assuntos
Infecções por HIV , Profissionais do Sexo , Feminino , Guatemala , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Teste de HIV , Humanos , México/epidemiologia
2.
Int J Toxicol ; 41(4): 291-296, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35656559

RESUMO

The IQ Consortium NHP Reuse Working Group (WG) comprises members from 15 pharmaceutical and biotechnology companies. In 2020, the WG developed and distributed a detailed questionnaire on protein non-naïve NHP reuse to the WG member companies. The WG received responses from key stakeholders including principal investigators, facility managers, animal welfare officers and research scientists. This paper's content reflects the consolidated opinion of the WG members and the questionnaire responses on the subject of NHP reuse within nonclinical programs at all stages of research and development. Many of the pharmaceutical companies represented in the working group or participating in the questionnaire have already achieved some level of NHP reuse in their nonclinical programs, but the survey results suggested that there is significant potential to increase NHP reuse further and a need to understand the considerations involved in reuse more clearly. The WG has also focused carefully on the inherent concerns and risks of implementing protein non-naive NHP reuse and has evaluated the best methods of risk assessment and decision-making. This paper presents a discussion on the challenges and opportunities surrounding protein non-naïve NHP reuse and aims to stimulate further industry dialogue on the subject and provide guidance for pharmaceutical companies to establish roadmaps and decision trees enabling increased protein non-naïve NHP reuse. In addition, this paper represents a solid basis for collaborative engagement between pharmaceutical and biotechnology companies with contract research organizations (CROs) to discuss how the availability of protein non-naïve NHP within CROs can be better leveraged for their use within nonclinical studies.


Assuntos
Descoberta de Drogas , Primatas , Animais , Avaliação Pré-Clínica de Medicamentos/métodos , Indústria Farmacêutica/métodos , Preparações Farmacêuticas
3.
AIDS Behav ; 24(10): 2906-2917, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32277308

RESUMO

A dearth of empirical research exists on female sex workers in Central America who begin selling sex under age 18. Data were collected from adult female sex workers (N = 1216) sampled using census and modified time-location sampling in three urban centers of Guatemala. In adjusted analyses, female sex workers who entered the sex trade under age 16 years were more likely to be HIV positive (AOR = 4.6, 95% CI 1.6, 13.2), have not received HIV education in their first year of sex trade (AOR = 2.8, 95% CI 1.5, 5.5), have experienced violence to force commercial sex (AOR = 4.6, 95% CI 2.2, 9.8) and have not used condoms in their first month (AOR = 2.8, 95% CI 1.3, 6.1) , relative to those who entered as adults. An interaction between age at entry and foreign migration at entry was found for HIV risk. Efforts to prevent adolescent sex trade entry are needed and may also help to reduce HIV rates in Guatemala.


Assuntos
Preservativos/estatística & dados numéricos , Infecções por HIV/diagnóstico , Trabalho Sexual/estatística & dados numéricos , Profissionais do Sexo , Adolescente , Adulto , Estudos Transversais , Feminino , Guatemala/epidemiologia , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Humanos , Comportamento Sexual , Migrantes
4.
J Ethn Subst Abuse ; 19(4): 503-520, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30795721

RESUMO

We explored the association of international migration with substance use and HIV/STI risk factors among female sex workers (FSW). Using modified time-location sampling, we recruited 266 FSW at the Mexico-Guatemala border. Crude and adjusted logistic regression models were used to evaluate the relationships. HIV risks, such as frequent hard drug use and drug use in another country, were greater for migrant compared to nonmigrant FSW. However, more migrant versus nonmigrant FSW reported consistent condom use with clients and having a health card. Our study highlights regional patterns of substance use among FSW and risk or protective behaviors related to migration status.


Assuntos
Emigração e Imigração/estatística & dados numéricos , Infecções por HIV/epidemiologia , Trabalho Sexual/estatística & dados numéricos , Profissionais do Sexo/estatística & dados numéricos , Infecções Sexualmente Transmissíveis/epidemiologia , Migrantes/estatística & dados numéricos , Adulto , Feminino , Guatemala , Humanos , México , Prevalência , Fatores de Risco , Transtornos Relacionados ao Uso de Substâncias , Sexo sem Proteção/estatística & dados numéricos , Adulto Jovem
5.
Anthropol Med ; 27(4): 363-379, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31801356

RESUMO

The Mexico-Guatemala border is the site of significant movement of people whose principal destination is the USA. The first step, to cross Mexico, is considered as one of the most dangerous routes in the world for undocumented migrants. For some male migrants and displaced persons from Honduras, El Salvador and Guatemala, initiating sex work in the Mexican border city of Tapachula has become a way to earn money to survive during the trip northward - providing funds to keep traveling and decrease the danger of being killed or kidnaped by organized crime groups. Non-injected drug use during sex work with men and/or women is a common praxis for this purpose, and is linked to HIV risk activities such as unprotected sex. Our study is based on ethnographic fieldwork with observation and interviews and within a relational approach understanding the processes subject/structure, sociopolitical/cultural and global/local, not as oppositions, rather as linkages visible through actors' points of view and praxis. The productions of politics and cultures related to structural vulnerability to HIV infection are embedded in local and global borderization processes where legal and illegal transnational forces, states' frameworks and social groups play a linked role. The economies of structural, symbolic and direct violence affect migratory patterns, institutional interactions and social and cultural relations with the local population. In this context, social representations and praxis about unprotected sex and drug use are the locus of struggling bodies at the border.


Assuntos
Infecções por HIV/etnologia , Trabalho Sexual/etnologia , Migrantes , Violência/etnologia , Adolescente , Adulto , Antropologia Médica , Feminino , Guatemala/etnologia , Humanos , Masculino , México/etnologia , Refugiados , Transtornos Relacionados ao Uso de Substâncias/etnologia , Adulto Jovem
6.
AIDS Behav ; 23(4): 900-907, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30377979

RESUMO

We piloted a health navigation strategy to promote timely linkage to care among men who have sex with men (MSM) and transgender women (TW) recently diagnosed with HIV in Guatemala City. We used a mixed-methods approach, integrating quantitative data collected during clinic visits and qualitative data from in-depth interviews, to characterize acceptability of navigation and time to linkage, defined as having the first clinical care visit. Out of 54 participants who enrolled in the pilot (n = 52 MSM; n = 2 TW), 50 (92.6%) accepted navigation and all were linked to care. Median time to linkage was 3 days (Interquartile Range 2-5 days). In qualitative interviews, participants expressed feeling scared and alone following their diagnosis and appreciated the support of a navigator, especially when they did not feel they could access their existing support networks. Future research and evaluation should continue to assess how to best use health navigation to support key populations recently diagnosed with HIV.


Assuntos
Continuidade da Assistência ao Paciente , Infecções por HIV/tratamento farmacológico , Acessibilidade aos Serviços de Saúde , Homossexualidade Masculina/psicologia , Navegação de Pacientes , Transexualidade/psicologia , Adulto , Feminino , Guatemala/epidemiologia , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Humanos , Entrevistas como Assunto , Masculino , Projetos Piloto , Pesquisa Qualitativa , Minorias Sexuais e de Gênero , Pessoas Transgênero/psicologia
7.
BMC Int Health Hum Rights ; 18(1): 9, 2018 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-29394893

RESUMO

BACKGROUND: Migrant women are over-represented in the sex industry, and migrant sex workers experience disproportionate health inequities, including those related to health access, HIV and sexually transmitted infections (STIs), and violence. Despite calls for occupational sex work interventions situated in labour rights frameworks, there remains a paucity of evidence pertaining to migrant sex workers' needs and realities, particularly within Mexico and Central America. This study investigated migrant sex workers' narratives regarding the ways in which structural features of work environments shape vulnerability and agency related to HIV/STI prevention and violence at the Guatemala-Mexico border. METHODS: Drawing on theoretical perspectives on risk environments and structural determinants of HIV in sex work, we analyzed in-depth interviews, focus groups, and ethnographic fieldwork conducted with 39 migrant sex workers in indoor work environments between 2012 and 2015 in Tecún Umán, Guatemala. RESULTS: Participant narratives revealed the following intersecting themes to be most closely linked to safety and agency to engage in HIV/STI prevention: physical features of indoor work environments (e.g., physical layout of venue, proximity to peers and third parties); social norms and practices for alcohol use within the workplace; the existence and nature of management practices and policies on health and safety practices; and economic influences relating to control over earnings and clients. Across work environments, health and safety were greatly shaped by human rights concerns stemming from workplace interactions with police, immigration authorities, and health authorities. CONCLUSIONS: Physical isolation, establishment norms promoting alcohol use, restricted economic agency, and human rights violations related to sex work policies and immigration enforcement were found to exacerbate risks. However, some establishment policies and practices promoted 'enabling environments' for health and safety, supporting HIV/STI prevention, economic agency, and protection from violence and exploitation; these practices and policies were especially crucial for recent migrants. Policy reforms and structural workplace interventions tailored to migrant sex workers' needs are recommended to promote improved working conditions and migrant sex workers' health, safety, and human rights.


Assuntos
Infecções por HIV/prevenção & controle , Direitos Humanos/legislação & jurisprudência , Saúde Ocupacional/normas , Profissionais do Sexo , Migrantes , Adulto , Antropologia Cultural , América Central/etnologia , Feminino , Grupos Focais , Guatemala , Humanos , Entrevistas como Assunto , Pesquisa Qualitativa , Local de Trabalho/psicologia
8.
Bioorg Med Chem Lett ; 27(12): 2689-2694, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28454672

RESUMO

A new class of betulin-derived α-keto amides was identified as HIV-1 maturation inhibitors. Through lead optimization, GSK8999 was identified with IC50 values of 17nM, 23nM, 25nM, and 8nM for wild type, Q369H, V370A, and T371A respectively. When tested in a panel of 62 HIV-1 isolates covering a diversity of CA-SP1 genotypes including A, AE, B, C, and G using a PBMC based assay, GSK8999 was potent against 57 of 62 isolates demonstrating an improvement over the first generation maturation inhibitor BVM. The data disclosed here also demonstrated that the new α-keto amide GSK8999 has a mechanism of action consistent with inhibition of the proteolytic cleavage of CA-SP1.


Assuntos
Amidas/farmacologia , Fármacos Anti-HIV/farmacologia , Descoberta de Drogas , HIV-1/efeitos dos fármacos , Polimorfismo Genético/efeitos dos fármacos , Triterpenos/farmacologia , Produtos do Gene gag do Vírus da Imunodeficiência Humana/antagonistas & inibidores , Amidas/síntese química , Amidas/química , Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/química , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Estrutura Molecular , Polimorfismo Genético/genética , Relação Estrutura-Atividade , Triterpenos/química , Produtos do Gene gag do Vírus da Imunodeficiência Humana/genética
9.
AIDS Behav ; 21(7): 2033-2045, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28238120

RESUMO

This study assessed correlates of inconsistent condom use with casual partners and the prevalence of sexual risk behaviors and STIs in the Mexico/Guatemala border region using a sample of 392 migrants (303 men, 85 women) who reported current substance use or problem drinking. We ran separate univariate logistic regression models for men and women, and multivariate logistic regression models for men only. Prevalence of syphilis was 1.2% among women and 2.3% among men; HIV prevalence was 2.4% among women and 1.3% among men. Inconsistent condom use with casual partners was higher in women with greater education and lower among women who sold sex. In men, less access to free condoms, drug use with sexual partners, and drug use before sex were independently associated with inconsistent condom use with casual partners. Sexual and substance use risk behaviors were common, and HIV/STI prevention efforts should target both genders and expand beyond most-at risk populations.


Assuntos
Preservativos/estatística & dados numéricos , Infecções por HIV/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Sífilis/epidemiologia , Migrantes/estatística & dados numéricos , Sexo sem Proteção/estatística & dados numéricos , Adulto , Estudos Transversais , Feminino , Guatemala/epidemiologia , Infecções por HIV/prevenção & controle , Humanos , Modelos Logísticos , Masculino , México/epidemiologia , Prevalência , Fatores de Risco , Assunção de Riscos , Sexo Seguro/estatística & dados numéricos , Comportamento Sexual/estatística & dados numéricos , Parceiros Sexuais , Infecções Sexualmente Transmissíveis/epidemiologia , Adulto Jovem
10.
Molecules ; 22(1)2017 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-28098838

RESUMO

Silymarin is the most commonly used herbal medicine by patients with chronic liver disease. Silymarin flavonolignans undergo rapid first-pass metabolism primarily by glucuronidation. The aims of this investigation were: (1) to determine the association of UGT1A1*28 polymorphism with the area under the plasma concentration-time curves (AUCs) for silybin A (SA) and silybin B (SB); (2) to evaluate the effect of UGT1A1*28 polymorphism on the profile of flavonolignan glucuronide conjugates found in the plasma; and (3) to investigate the role of UGT1A1 enzyme kinetics on the pharmacokinetics of SA and SB. AUCs and metabolic ratios for thirty-three patients with chronic liver disease administered oral doses of silymarin were compared between different UGT1A1*28 genotypes. The AUCs, metabolic ratios, and the profiles of major SA and SB glucuronides did not differ significantly among the three UGT1A1 genotypes. In contrast, an increase in the proportion of sulfated flavonolignan conjugates in plasma was observed in subjects with UGT1A1*28/*28 genotype compared to subjects carrying wild type alleles. Differences in SA and SB in vitro intrinsic clearance estimates for UGTIA1 correlated inversely with SA and SB exposures observed in vivo indicating a major role for UGT1A1 in silymarin metabolism. In addition, a significant difference in the metabolic ratio observed between patients with NAFLD and HCV suggests that any effect of UGT1A1 polymorphism may be obscured by a greater effect of liver disease on the pharmacokinetics of silymarin. Taken together, these results suggest the presence of the UGT1A1*28 allele does not contribute significantly to a large inter-subject variability in the pharmacokinetics of silybin A and silybin B which may obscure the ability to detect beneficial effects of silymarin in patients with liver disease.


Assuntos
Flavonolignanos/metabolismo , Glucuronosiltransferase/genética , Hepatite C/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Silimarina/metabolismo , Adulto , Alelos , Feminino , Flavonolignanos/administração & dosagem , Flavonolignanos/farmacocinética , Genótipo , Hepatite C/sangue , Hepatite C/genética , Humanos , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/genética , Testes Farmacogenômicos , Polimorfismo Genético , Silimarina/administração & dosagem , Silimarina/farmacocinética
11.
Am J Physiol Gastrointest Liver Physiol ; 311(5): G903-G919, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27659423

RESUMO

Knockout technology has proven useful for delineating functional roles of specific genes. Here we describe and provide an explanation for striking pathology that occurs in a subset of genetically engineered mice expressing a rat CaVß2a transgene under control of the cardiac α-myosin heavy chain promoter. Lesions were limited to mice homozygous for transgene and independent of native Cacnb2 genomic copy number. Gross findings included an atrophied pancreas; decreased adipose tissue; thickened, orange intestines; and enlarged liver, spleen, and abdominal lymph nodes. Immune cell infiltration and cell engulfment by macrophages were associated with loss of pancreatic acinar cells. Foamy macrophages diffusely infiltrated the small intestine's lamina propria, while similar macrophage aggregates packed liver and splenic red pulp sinusoids. Periodic acid-Schiff-positive, diastase-resistant, iron-negative, Oil Red O-positive, and autofluorescent cytoplasm was indicative of a lipid storage disorder. Electron microscopic analysis revealed liver sinusoids distended by clusters of macrophages containing intracellular myelin "swirls" and hepatocytes with enlarged lysosomes. Additionally, build up of cholesterol, cholesterol esters, and triglycerides, along with changes in liver metabolic enzyme levels, were consistent with a lipid processing defect. Because of this complex pathology, we examined the transgene insertion site. Multiple transgene copies inserted into chromosome 19; at this same site, an approximate 180,000 base pair deletion occurred, ablating cholesterol 25-hydroxylase and partially deleting lysosomal acid lipase and CD95 Loss of gene function can account for the altered lipid processing, along with hypertrophy of the immune system, which define this phenotype, and serendipitously provides a novel mouse model of lysosomal storage disorder.


Assuntos
Canais de Cálcio Tipo L/genética , Colesterol/metabolismo , Doenças por Armazenamento dos Lisossomos/genética , Triglicerídeos/metabolismo , Animais , Modelos Animais de Doenças , Hepatócitos/metabolismo , Hepatócitos/patologia , Fígado/metabolismo , Fígado/patologia , Doenças por Armazenamento dos Lisossomos/metabolismo , Doenças por Armazenamento dos Lisossomos/patologia , Lisossomos/metabolismo , Lisossomos/patologia , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , Camundongos Transgênicos , Regiões Promotoras Genéticas , Baço/metabolismo , Baço/patologia
12.
Cult Health Sex ; 18(9): 965-79, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27439656

RESUMO

Despite reports of high levels of violence among women migrants in Central America, limited evidence exists regarding the health and safety of migrant sex workers in Central America. This study is based on 16 months of field research (November 2012-February 2014), including ethnographic fieldwork, in-depth interviews, and focus groups conducted with 52 internal and international migrant female sex workers in Tecún Umán and Quetzaltenango, Guatemala, key transit and destination communities for both international and internal migrants. The analysis explored migration-related determinants of susceptibility to violence experienced by migrant sex workers across different phases of migration. Violence in home communities and economic considerations were key drivers of migration. Unsafe transit experiences (eg undocumented border crossings) and negative interactions with authorities in destination settings (eg extortion) contributed to migrant sex workers' susceptibility to violence, while enhanced access to information on immigration policies and greater migration and sex work experience were found to enhance agency and resilience. Findings suggest the urgent need for actions that promote migrant sex workers' safety in communities of origin, transit, and destination, and programmes aimed at preventing and addressing human rights violations within the context of migration and sex work.


Assuntos
Segurança , Profissionais do Sexo/psicologia , Migrantes , Violência , Adulto , Antropologia Cultural , Emigração e Imigração , Feminino , Grupos Focais , Guatemala , Direitos Humanos , Humanos , Pesquisa Qualitativa
13.
J Neurosci ; 34(10): 3733-42, 2014 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-24599471

RESUMO

µ-Opioid agonists have no effect on calcium currents (I(Ca)) in neurohypophysial terminals when recorded using the classic whole-cell patch-clamp configuration. However, µ-opioid receptor (MOR)-mediated inhibition of I(Ca) is reliably demonstrated using the perforated-patch configuration. This suggests that the MOR-signaling pathway is sensitive to intraterminal dialysis and is therefore mediated by a readily diffusible second messenger. Using the perforated patch-clamp technique and ratio-calcium-imaging methods, we describe a diffusible second messenger pathway stimulated by the MOR that inhibits voltage-gated calcium channels in isolated terminals from the rat neurohypophysis (NH). Our results show a rise in basal intracellular calcium ([Ca(2+)]i) in response to application of [D-Ala(2)-N-Me-Phe(4),Gly5-ol]-Enkephalin (DAMGO), a MOR agonist, that is blocked by D-Phe-Cys-Tyr-D-Trp-Orn-Thr-Pen-Thr-NH2 (CTOP), a MOR antagonist. Buffering DAMGO-induced changes in [Ca(2+)]i with BAPTA-AM completely blocked the inhibition of both I(Ca) and high-K(+)-induced rises in [Ca(2+)]i due to MOR activation, but had no effect on κ-opioid receptor (KOR)-mediated inhibition. Given the presence of ryanodine-sensitive stores in isolated terminals, we tested 8-bromo-cyclic adenosine diphosphate ribose (8Br-cADPr), a competitive inhibitor of cyclic ADP-ribose (cADPr) signaling that partially relieves DAMGO inhibition of I(Ca) and completely relieves MOR-mediated inhibition of high-K(+)-induced and DAMGO-induced rises in [Ca(2+)]i. Furthermore, antagonist concentrations of ryanodine completely blocked MOR-induced increases in [Ca(2+)]i and inhibition of I(Ca) and high-K(+)-induced rises in [Ca(2+)]i while not affecting KOR-mediated inhibition. Antagonist concentrations of ryanodine also blocked MOR-mediated inhibition of electrically-evoked increases in capacitance. These results strongly suggest that a key diffusible second messenger mediating the MOR-signaling pathway in NH terminals is [Ca(2+)]i released by cADPr from ryanodine-sensitive stores.


Assuntos
Cálcio/metabolismo , Neuro-Hipófise/metabolismo , Terminações Pré-Sinápticas/metabolismo , Receptores Opioides mu/antagonistas & inibidores , Rianodina/farmacologia , Analgésicos Opioides/metabolismo , Analgésicos Opioides/farmacologia , Animais , Ala(2)-MePhe(4)-Gly(5)-Encefalina/metabolismo , Ala(2)-MePhe(4)-Gly(5)-Encefalina/farmacologia , Masculino , Neuro-Hipófise/efeitos dos fármacos , Terminações Pré-Sinápticas/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Receptores Opioides mu/fisiologia , Rianodina/metabolismo
14.
AIDS Behav ; 19(9): 1609-18, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25432875

RESUMO

We assessed HIV and STI prevalence, risk behaviors and factors associated with HIV infection in men who have sex with men (MSM) in Guayaquil, Ecuador. Respondent-driven sampling was used to recruit 400 MSM in 2011-2012. Participants completed a computer-assisted self-interview and provided blood samples. Statistical analysis accounted for differential probability of selection and for recruitment patterns. HIV prevalence was 11.3 %, HSV-2 30.2 %, active syphilis 6.9 % and hepatitis B 1.2 %. In the previous 12 months, 84 % of MSM reported casual male sex partners and 25 % sex work. Only 48 % of MSM consistently used condoms with male partners and 54 % had ever been tested for HIV. Of 17 % of MSM reporting a female partner, consistent condom use was 6 %. HIV infection was associated with age 25 or older, active syphilis and homosexual self-identification. Findings suggest continuing HIV risk and a need to strengthen prevention and testing among MSM.


Assuntos
Infecções por HIV/prevenção & controle , Homossexualidade Masculina/psicologia , Assunção de Riscos , Infecções Sexualmente Transmissíveis/prevenção & controle , Adolescente , Adulto , Equador/epidemiologia , Infecções por HIV/epidemiologia , Hepatite B/epidemiologia , Herpes Genital/epidemiologia , Homossexualidade Masculina/estatística & dados numéricos , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prevalência , Trabalho Sexual , Parceiros Sexuais , Infecções Sexualmente Transmissíveis/epidemiologia , Fatores Socioeconômicos , Sífilis/epidemiologia , Adulto Jovem
15.
J Virol ; 87(13): 7463-70, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23616665

RESUMO

Human immunodeficiency virus type 1 (HIV-1) variants show considerable geographical separation across the world, but there is limited information from Central America. We provide the first detailed investigation of the genetic diversity and molecular epidemiology of HIV-1 in six Central American countries. Phylogenetic analysis was performed on 625 HIV-1 pol gene sequences collected between 2002 and 2010 in Honduras, El Salvador, Nicaragua, Costa Rica, Panama, and Belize. Published sequences from neighboring countries (n = 57) and the rest of the world (n = 740) were included as controls. Maximum likelihood methods were used to explore phylogenetic relationships. Bayesian coalescence-based methods were used to time HIV-1 introductions. Nearly all (98.9%) Central American sequences were of subtype B. Phylogenetic analysis revealed that 437 (70%) sequences clustered within five significantly supported monophyletic clades formed essentially by Central American sequences. One clade contained 386 (62%) sequences from all six countries; the other four clades were smaller and more country specific, suggesting discrete subepidemics. The existence of one large well-supported Central American clade provides evidence that a single introduction of HIV-1 subtype B in Central America accounts for most current cases. An introduction during the early phase of the HIV-1 pandemic may explain its epidemiological success. Moreover, the smaller clades suggest a subsequent regional spread related to specific transmission networks within each country.


Assuntos
Evolução Molecular , Variação Genética , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , HIV-1/genética , Filogenia , Sequência de Bases , Teorema de Bayes , América Central/epidemiologia , Infecções por HIV/transmissão , HIV-1/classificação , Humanos , Funções Verossimilhança , Modelos Genéticos , Epidemiologia Molecular , Dados de Sequência Molecular , Prevalência , Alinhamento de Sequência , Análise de Sequência de DNA , Produtos do Gene pol do Vírus da Imunodeficiência Humana/genética
16.
AIDS Behav ; 18(1): 88-98, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23620242

RESUMO

This study characterized the HIV epidemic among men who have sex with men (MSM) in Quito, Ecuador and contrasted risk patterns with other STI's. 416 MSM ages 15 years and older were recruited using respondent-driven sampling in 2010-2011. Biological testing and a self-interview survey assessed HIV and STI infections and risk behaviors. Analysis incorporated recruiter-level variables and clustering adjustments to control for recruitment patterns. We identify high levels of HIV (11 %), HSV-2 (14 %) and active syphilis (5.5 %) infections, low levels of lifetime HIV testing (57 %), limited knowledge of HIV and STI's (<48 %) and limited consistent condom use independent of partner type (<40 %). Sex work was associated with all infections while associations with residential location, how casual partners are met and other variables, varied. Scale-up of behavioral prevention and HIV testing is urgently needed. Interventions should target male sex workers and exploit differential patterns of HIV-STI risk to stay ahead of the epidemic.


Assuntos
Infecções por HIV/epidemiologia , Necessidades e Demandas de Serviços de Saúde , Homossexualidade Masculina/estatística & dados numéricos , Prevenção Primária/organização & administração , Infecções Sexualmente Transmissíveis/epidemiologia , Adolescente , Adulto , Equador/epidemiologia , Infecções por HIV/diagnóstico , Infecções por HIV/psicologia , Hepatite B/epidemiologia , Herpes Genital/epidemiologia , Herpes Simples/epidemiologia , Herpesvirus Humano 2 , Humanos , Masculino , Prevenção Primária/normas , Assunção de Riscos , Infecções Sexualmente Transmissíveis/diagnóstico , Infecções Sexualmente Transmissíveis/prevenção & controle , Infecções Sexualmente Transmissíveis/psicologia , Sífilis/epidemiologia , Adulto Jovem
17.
Foods ; 13(3)2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38338609

RESUMO

In this work, alpha-tocopherol (α-TOC) was encapsulated in poly(lactic acid) nanoparticles (PLA NPs) and added to low-density polyethylene (LDPE) films with the aim of producing an active film for food packaging applications. PLA NPs loaded with α-TOC were produced through nanoprecipitation and dried using two methods (freeze-dryer and oven). LDPE-based films with final polymeric matrix concentrations of 10 and 20 g/kg were then produced through blow extrusion. The results showed that LDPE-based films loaded with α-TOC can be produced using blow extrusion, and a good distribution of PLA NPs can be obtained within the LDPE matrix as observed using scanning electron microscopy (SEM). The mechanical properties were affected by the incorporation of α-TOC and PLA NPs loaded with α-TOC, with the observation of a decrease in tensile strength and Young's Modulus values and an increase in elongation at break. Regarding water vapor permeability, the films showed a reduction in the values with the addition of α-TOC and PLA NPs loaded with α-TOC compared to the LDPE film (control). Films with α-TOC in the free state and loaded in PLA NPs showed antioxidant activity, but their behavior was affected by the encapsulation process.

18.
Alcohol Clin Exp Res ; 37(6): 933-40, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23421938

RESUMO

BACKGROUND: Voltage-gated calcium channels (VGCCs) in rat neurohypophysial terminals exhibit molecular tolerance to alcohol, including desensitization to the drug and increased current density, after 3 weeks of alcohol drinking. Moreover, after this time, terminals from drinking rats exhibit diminished alcohol inhibition of vasopressin (AVP) release. METHODS: We took advantage of organotypic cultures (explants) of the hypothalamo-neurohypophysial system (HNS) to extend our analysis of molecular tolerance to 2 classes of the VGCC. The isolated HNS explant allows much finer temporal resolution of molecular tolerance than do voluntary drinking paradigms. After exposure of the HNS explant to alcohol, terminals are isolated by mechanical treatment and plated in a dish. Patch clamp recording techniques are used to obtain VGCC currents, and immunohistochemistry is used to determine VGCC distribution. A release assay is used to provide functional readout of AVP release. RESULTS: We show that even a brief, 1-hour exposure to a clinically relevant concentration of alcohol is sufficient to evoke similar changes to those observed after several weeks of exposure. Acute ethanol (EtOH) exposure inhibits high K(+) -induced AVP release from naïve terminals. However, terminals pre-exposed to 20 mM EtOH for 1 hour become tolerant to EtOH, and subsequent exposure has significantly less effect on high K(+) -induced AVP release. Electrophysiological recordings indicate that among different types of VGCCs present in the neuronal terminal, the L-type is the most affected by alcohol. The current density of L-type current is significantly increased (approximately 50%), while its responsiveness to alcohol is significantly diminished (approximately 50%), after brief alcohol exposure. Fluorescent imaging results were consistent with the electrophysiology and suggest that the increased current density of VGCCs after brief exposure is attributable to combined synthesis of 1.2 and 1.3 subtypes of the L-type VGCC and redistribution of channel protein into terminal plasma membrane. CONCLUSIONS: These data indicate that a brief alcohol exposure affects subsequent alcohol sensitivity of VGCCs and neuropeptide release from presynaptic terminals.


Assuntos
Arginina Vasopressina/metabolismo , Canais de Cálcio Tipo L/efeitos dos fármacos , Depressores do Sistema Nervoso Central/farmacologia , Tolerância a Medicamentos/fisiologia , Etanol/farmacologia , Neuro-Hipófise/efeitos dos fármacos , Terminações Pré-Sinápticas/efeitos dos fármacos , Animais , Canais de Cálcio Tipo L/fisiologia , Eletrofisiologia , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/fisiologia , Técnicas In Vitro , Masculino , Técnicas de Patch-Clamp , Neuro-Hipófise/fisiologia , Terminações Pré-Sinápticas/fisiologia , Ratos , Ratos Sprague-Dawley
19.
Salud Publica Mex ; 55 Suppl 1: S65-78, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23918059

RESUMO

OBJECTIVE: This systematic review aims to synthesize articles, abstracts and reports of HIV prevalence studies conducted among men who have sex with men (MSM) and female sex workers (FSW) in Latin America and the Caribbean (LAC). MATERIALS AND METHODS: Authors searched online databases and collected gray literature on HIV prevalence among MSM and FSW from LAC. Year, location, sampling methodology, study design, sample size, HIV prevalence and confidence intervals were abstracted. RESULTS: A total of 73 studies, dating from 1986 to 2010 were included.The median prevalences for MSM and FSW were 10.6% (interquartile range: 7.4- 17.4) and 2.6% (IQR: 0.6 -4.2), respectively. Variability was high, especially for MSM. The majority of studies recruited participants using convenience methods. CONCLUSION: HIV prevalence among MSM was higher than that among FSW. Sampling techniques should be standardized for future studies, prioritizing probability methods.


Assuntos
Infecções por HIV/epidemiologia , Região do Caribe/epidemiologia , Humanos , América Latina/epidemiologia , Prevalência
20.
Front Cell Infect Microbiol ; 13: 1195803, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37284501

RESUMO

Biofilms are complex structures with an intricate relationship between the resident microorganisms, the extracellular matrix, and the surrounding environment. Interest in biofilms is growing exponentially given its ubiquity in so diverse fields such as healthcare, environmental and industry. Molecular techniques (e.g., next-generation sequencing, RNA-seq) have been used to study biofilm properties. However, these techniques disrupt the spatial structure of biofilms; therefore, they do not allow to observe the location/position of biofilm components (e.g., cells, genes, metabolites), which is particularly relevant to explore and study the interactions and functions of microorganisms. Fluorescence in situ hybridization (FISH) has been arguably the most widely used method for an in situ analysis of spatial distribution of biofilms. In this review, an overview on different FISH variants already applied on biofilm studies (e.g., CLASI-FISH, BONCAT-FISH, HiPR-FISH, seq-FISH) will be explored. In combination with confocal laser scanning microscopy, these variants emerged as a powerful approach to visualize, quantify and locate microorganisms, genes, and metabolites inside biofilms. Finally, we discuss new possible research directions for the development of robust and accurate FISH-based approaches that will allow to dig deeper into the biofilm structure and function.


Assuntos
Biofilmes , Hibridização in Situ Fluorescente/métodos , Microscopia Confocal/métodos
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