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1.
Nicotine Tob Res ; 25(1): 43-49, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36103393

RESUMEN

INTRODUCTION: Proactive outreach offering tobacco treatment is a promising strategy outside of clinical settings, but little is known about factors for engagement. The study objective is to examine the impact of caller area code in a proactive, phone-based outreach strategy on consenting low-income smokers to a quitline e-referral. AIMS AND METHODS: This pragmatic randomized trial included unassisted adult smokers (n = 685), whose preferred language was English or Spanish, in a Los Angeles safety-net health system. Patients were randomized to receive a call from a local or generic toll-free area code. Log-binomial regression was used to examine the association between area code and consent to a quitline e-referral, adjusted for age, gender, language, and year. RESULTS: Overall, 52.1% of the patients were contacted and, among those contacted, 30% consented to a referral. The contact rate was higher for the local versus generic area code, although not statistically significant (55.6% vs. 48.7%, p = .07). The consent rate was higher in the local versus generic area code group (adjusted prevalence ratio 1.29, 95% CI 1.01-1.65) and also higher for patients under 61 years old than over (adjusted prevalence ratio 1.47, 95% CI 1.07-2.01), and Spanish-speaking than English-speaking patients (adjusted prevalence ratio 1.40, 95% CI 1.05-1.86). CONCLUSIONS: Proactive phone-based outreach to unassisted smokers in a safety net health system increased consent to a quitline referral when local (vs. generic) area codes were used to contact patients. While contact rate did not differ by area code, proactive phone-based outreach was effective for engaging younger and Spanish-speaking smokers. IMPLICATIONS: Population-based proactive phone-based outreach from a caller with a local area code to unassisted smokers in a safety net health system increases consent to an e-referral for quitline services. Findings suggest that a proactive phone-based outreach, a population-based strategy, is an effective strategy to build on the visit-based model and offer services to tobacco users, regardless of the motivational levels to quit.


Asunto(s)
Fumadores , Cese del Hábito de Fumar , Adulto , Humanos , Persona de Mediana Edad , Consejo , Dispositivos para Dejar de Fumar Tabaco , Teléfono
2.
J Gen Intern Med ; 37(6): 1400-1407, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34505234

RESUMEN

BACKGROUND: Since the advent of COVID-19, accelerated adoption of systems that reduce face-to-face encounters has outpaced training and best practices. Electronic consultations (eConsults), structured communications between PCPs and specialists regarding a case, have been effective in reducing face-to-face specialist encounters. As the health system rapidly adapts to multiple new practices and communication tools, new mechanisms to measure and improve performance in this context are needed. OBJECTIVE: To test whether feedback comparing physicians to top performing peers using co-specialists' ratings improves performance. DESIGN: Cluster-randomized controlled trial PARTICIPANTS: Eighty facility-specialty clusters and 214 clinicians INTERVENTION: Providers in the feedback arms were sent messages that announced their membership in an elite group of "Top Performers" or provided actionable recommendations with feedback for providers that were "Not Top Performers." MAIN MEASURES: The primary outcomes were changes in peer ratings in the following performance dimensions after feedback was received: (1) elicitation of information from primary care practitioners; (2) adherence to institutional clinical guidelines; (3) agreement with peer's medical decision-making; (4) educational value; (5) relationship building. KEY RESULTS: Specialists showed significant improvements on 3 of the 5 consultation performance dimensions: medical decision-making (odds ratio 1.52, 95% confidence interval 1.08-2.14, p<.05), educational value (1.86, 1.17-2.96) and relationship building (1.63, 1.13-2.35) (both p<.01). CONCLUSIONS: The pandemic has shed light on clinicians' commitment to professionalism and service as we rapidly adapt to changing paradigms. Interventions that appeal to professional norms can help improve the efficacy of new systems of practice. We show that specialists' performance can be measured and improved with feedback using aspirational norms. TRIAL REGISTRATION: clinicaltrials.gov NCT03784950.


Asunto(s)
Benchmarking , COVID-19 , COVID-19/epidemiología , Electrónica , Humanos , Los Angeles , Derivación y Consulta
4.
Mol Biol Rep ; 43(12): 1359-1369, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27752939

RESUMEN

There is scarce information about the link between specific single-nucleotide polymorphisms (SNPs) and risk of liver disease among Latinos, despite the disproportionate burden of disease among this population. Our aim was to investigate nine SNPs in or near the following genes: PNPLA3, LYPLAL1, PPP1R3B, GCKR, NCAN, IRS1, PPARG, and ADIPOR2 and examine their association with persistently elevated alanine aminotransferase (ALT) or aspartate aminotransferase (AST) levels in Mexican adults. Data and samples were collected from 741 participants in the Mexican Health Worker Cohort Study, in Cuernavaca, Mexico. We identified 207 cases who had persistently elevated levels of ALT or AST (≥40 U/L) and 534 controls with at least two consecutive normal ALT or AST results in a 6 month period, during 2004-2006 and 2011-2013. TaqMan assays were used to genotype the SNPs. The risk allele of PNPLA3 rs738409 was found to be associated with persistently elevated levels of ALT or AST, adjusting for age, sex, BMI, type 2 diabetes, and ancestry: (OR 2.28, 95 % CI 1.13, 4.58). A significant association was found between the LYPLAL1, PPP1R3B, and GCKR risk alleles and elevated ALT or AST levels among overweight/obese adults. These results suggest that among Mexicans, the PNPLA3 (rs738409), LYPLAL1 (rs12137855), PPP1R3B (rs4240624), and GCKR (rs780094) polymorphisms may be associated with a greater risk of chronic liver disease among overweight adults. This study is the first to examine these nine SNPs in a sample of adults in Mexico.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Alanina Transaminasa/sangre , Aspartato Aminotransferasas/sangre , Lipasa/genética , Lisofosfolipasa/genética , Proteínas de la Membrana/genética , Obesidad/genética , Proteína Fosfatasa 1/genética , Adulto , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Humanos , Masculino , México , Persona de Mediana Edad , Obesidad/sangre , Obesidad/enzimología , Sobrepeso/sangre , Sobrepeso/enzimología , Sobrepeso/genética , Polimorfismo de Nucleótido Simple
5.
BMC Gastroenterol ; 15: 91, 2015 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-26215250

RESUMEN

BACKGROUND: Autoimmune hepatitis causes chronic hepatitis and often leads to cirrhosis and death without treatment. We wanted to see if having access to primary care or insurance prior to diagnosis is associated with better outcomes for patients in an urban, public hospital with mostly socioeconomically disadvantaged Hispanic patients. METHODS: We did a retrospective study at our institution. Kaplan Meier survival analysis was done looking at transplant-free overall survival for patients diagnosed at our institution. The log-rank test was done to compare survival between patients with and without prior access to primary care, and between patients with and without insurance at diagnosis. RESULTS: Overall 5- and 10-year transplant-free overall survival was 91% (95% CI, 83-100%) and 75% (95% CI, 50-99%), respectively. Patients with primary care prior to diagnosis had significantly better transplant-free overall survival than those without (log rank test p = 0.019). Patients with primary care also had better clinical markers at diagnosis. Having insurance at diagnosis was not associated with better outcomes. CONCLUSIONS: Outcomes of autoimmune hepatitis are poor in our setting but access to primary care prior to diagnosis was associated with better outcomes. This is likely due to the important role that primary care plays in detecting disease and initiating treatment earlier. With the expansion of access to healthcare that the Affordable Care Act provides, future patients are likely to do better with even rare diseases like autoimmune hepatitis.


Asunto(s)
Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Hepatitis Autoinmune/terapia , Hispánicos o Latinos/estadística & datos numéricos , Seguro de Salud/estadística & datos numéricos , Atención Primaria de Salud/estadística & datos numéricos , Adulto , Femenino , Hepatitis Autoinmune/mortalidad , Hospitales de Condado , Hospitales Urbanos , Humanos , Trasplante de Hígado , Los Angeles/epidemiología , Masculino , Área sin Atención Médica , Persona de Mediana Edad , Estudios Retrospectivos , Factores Socioeconómicos , Tasa de Supervivencia
7.
Hepatology ; 57(1): 339-50, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22961591

RESUMEN

UNLABELLED: We have developed a novel model for depleting mouse hepatic stellate cells (HSCs) that has allowed us to clarify their contributions to hepatic injury and fibrosis. Transgenic (Tg) mice expressing the herpes simplex virus thymidine kinase gene (HSV-Tk) driven by the mouse GFAP promoter were used to render proliferating HSCs susceptible to killing in response to ganciclovir (GCV). Effects of GCV were explored in primary HSCs and in vivo. Panlobular damage was provoked to maximize HSC depletion by combining CCl(4) (centrilobular injury) with allyl alcohol (AA) (periportal injury), as well as in a bile duct ligation (BDL) model. Cell depletion in situ was quantified using dual immunofluorescence (IF) for desmin and GFAP. In primary HSCs isolated from both untreated wild-type (WT) and Tg mice, GCV induced cell death in ≈ 50% of HSCs from Tg, but not WT, mice. In TG mice treated with CCl(4) +AA+GCV, there was a significant decrease in GFAP and desmin-positive cells, compared to WT mice (≈ 65% reduction; P < 0.01), which was accompanied by a decrease in the expression of HSC-activation markers (alpha smooth muscle actin, beta platelet-derived growth factor receptor, and collagen I). Similar results were observed after BDL. Associated with HSC depletion in both fibrosis models, there was marked attenuation of fibrosis and liver injury, as indicated by Sirius Red/Fast Green, hematoxylin and eosin quantification, and serum alanine/aspartate aminotransferase. Hepatic expression of interleukin-10 and interferon-gamma was increased after HSC depletion. No toxicity of GCV in either WT or Tg mice accounted for the differences in injury. CONCLUSION: Activated HSCs significantly amplify the response to liver injury, further expanding this cell type's repertoire in orchestrating hepatic injury and repair.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Células Estrelladas Hepáticas/fisiología , Animales , Apoptosis , Tetracloruro de Carbono , Línea Celular , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Citocinas/metabolismo , Fibrosis , Ganciclovir , Proteína Ácida Fibrilar de la Glía , Hígado/inmunología , Hígado/patología , Masculino , Ratones , Ratones Transgénicos , Proteínas del Tejido Nervioso/genética , Regiones Promotoras Genéticas , Propanoles , Timidina Quinasa/genética , Proteínas Virales/genética
8.
Endosc Int Open ; 12(5): E642-E648, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38707596

RESUMEN

Background and study aims The Plan-Do-Study Act (PDSA) ramp is a framework that uses initial small changes to build consensus and momentum for subsequent, iterative process improvement. Our aim was to study its impact on endoscopy unit efficiency and throughput. Methods Following a granular time-and-motion analysis to evaluate baseline performance (phase 1) we instituted successive interventions and measured their impact on core efficiency metrics including procedure volume and turnover time (phases 2-3). Results We identified that inefficiency in turnover of anesthesia-supported endoscopy was the most crucial issue. Implementation of a pre-procedure anesthesia visit in phase 2 reduced turnover time by 15.5 minutes (95% confidence interval 3.9-27.1 minutes). Subsequent changes (phase 3) including front-loaded procedure scheduling and parallel in-room preparation resulted in an 18% increase in procedure volume. Conclusions The PDSA ramp model is an effective means of assessing operational processes, developing novel interventions, and building consensus to improve the real-world productivity in a resource-conscious manner.

9.
Learn Health Syst ; 8(3): e10442, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39036535

RESUMEN

Introduction: This article provides an overview of presentations and discussions from the inaugural Healthcare Delivery Science: Innovation and Partnerships for Health Equity Research (DESCIPHER) Symposium. Methods: The symposium brought together esteemed experts from various disciplines to explore models for translating evidence-based interventions into practice. Results: The symposium highlighted the importance of disruptive innovation in healthcare, the need for multi-stakeholder engagement, and the significance of family and community involvement in healthcare interventions. Conclusions: The article concluded with a call to action for advancing healthcare delivery science to achieve health equity.

10.
J Cell Physiol ; 228(3): 572-80, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22833357

RESUMEN

Inflammatory bowel disease (IBD) patients display elevated levels of intraluminal nitric oxide (NO). NO can react with other molecules to form toxic compounds, which has led to the idea that NO may be an important mediator of IBD. However, the cellular source of NO and how its production is regulated in the intestine are unclear. In this study we aimed to determine if intestinal myofibroblasts produce NO in response to the IBD-associated cytokines IL-1ß, TNFα, and IFNγ. Intestinal myofibroblasts were isolated from mice and found to express inducible nitric oxide synthase (iNOS) mRNA, but not endothelial NOS or neuronal NOS. Individual treatment of myofibroblasts with IL-1ß, TNFα, or IFNγ had no effect on NO production, but stimulation with combinations of these cytokines synergistically increased iNOS mRNA and protein expression. Treatment with TNFα or IFNγ increased cell surface expression of IFNγRI or TNFRII, respectively, suggesting that these cytokines act in concert to prime NO production by myofibroblasts. Impairment of NF-κB activity with a small molecule inhibitor was sufficient to prevent increased expression of IFNγRI or TNFRII, and inhibition of Akt, JAK/STAT, or NF-κB blocked nearly all NO production induced by combinatorial cytokine treatment. These data indicate that intestinal myofibroblasts require stimulation by multiple cytokines to produce NO and that these cytokines act through a novel pathway involving reciprocal cytokine receptor regulation and signaling by Akt, JAK/STAT, and NF-κB.


Asunto(s)
Citocinas/administración & dosificación , Miofibroblastos/efectos de los fármacos , Miofibroblastos/metabolismo , Óxido Nítrico/biosíntesis , Animales , Secuencia de Bases , Células Cultivadas , Humanos , Interferón gamma/administración & dosificación , Interleucina-1beta/administración & dosificación , Intestino Delgado/citología , Intestino Delgado/efectos de los fármacos , Intestino Delgado/metabolismo , Quinasas Janus/metabolismo , Ratones , FN-kappa B/metabolismo , Óxido Nítrico Sintasa de Tipo II/genética , Óxido Nítrico Sintasa de Tipo II/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores de Interferón/genética , Receptores de Interferón/metabolismo , Receptores Tipo II del Factor de Necrosis Tumoral/genética , Receptores Tipo II del Factor de Necrosis Tumoral/metabolismo , Factores de Transcripción STAT/metabolismo , Transducción de Señal/efectos de los fármacos , Factor de Necrosis Tumoral alfa/administración & dosificación , Receptor de Interferón gamma
11.
Am J Physiol Gastrointest Liver Physiol ; 304(7): G673-9, 2013 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-23348803

RESUMEN

Contraction of intestinal myofibroblasts (IMF) contributes to the development of strictures and fistulas seen in inflammatory bowel disease, but the mechanisms that regulate tension within these cells are poorly understood. In this study we investigated the role of nitric oxide (NO) signaling in C-type natriuretic peptide (CNP)-induced relaxation of IMF. We found that treatment with ODQ, a soluble guanylyl cyclase (sGC) inhibitor, or N(G)-nitro-L-arginine (L-NNA) or N(G)-monomethyl-L-arginine (L-NMMA), inhibitors of NO production, all impaired the relaxation of human and mouse IMF in response to CNP. ODQ, L-NNA, and L-NMMA also prevented CNP-induced elevations in cGMP concentrations, and L-NNA or L-NMMA blocked CNP-induced decreases in myosin light phosphorylation. IMF isolated from transgenic mice deficient in inducible nitric oxide synthase (iNOS) had reduced relaxation responses to CNP compared with IMF from control mice and were insensitive to the effects of ODQ, L-NNA, and L-NMMA on CNP treatment. Together these data indicate that stimulation of sGC though NO produced by iNOS activation is required for maximal CNP-induced relaxation in IMF.


Asunto(s)
Guanilato Ciclasa/metabolismo , Miofibroblastos/fisiología , Óxido Nítrico Sintasa de Tipo II/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Animales , GMP Cíclico/metabolismo , Guanilato Ciclasa/antagonistas & inhibidores , Humanos , Ratones , Relajación Muscular/efectos de los fármacos , Miofibroblastos/efectos de los fármacos , Péptido Natriurético Tipo-C/farmacología , Nitroarginina/farmacología , Oxadiazoles/farmacología , Quinoxalinas/farmacología , Receptores Citoplasmáticos y Nucleares/antagonistas & inhibidores , Guanilil Ciclasa Soluble , omega-N-Metilarginina/farmacología
12.
Am J Gastroenterol ; 108(4): 466-70, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23552303

RESUMEN

OBJECTIVES: We examined colorectal cancer (CRC) stage at presentation and mortality in a vulnerable population compared with nationally representative data. METHODS: CRC cases were identified from San Francisco General Hospital (SFGH) and the Surveillance Epidemiology and End Results (SEER) database. RESULTS: Fifty-five percent of the SFGH cohort presented with advanced disease, compared with 44% of the SEER cohort. Increased risk of advanced stage at presentation at SFGH compared with SEER was most evident among blacks and Asians. There was weak evidence for worse survival at SFGH compared with SEER overall. This varied by race with poorer survival at SFGH among whites and possibly blacks but some evidence for better survival among Asians. Among CRC patients at SFGH, Asians and Hispanics had better survival than whites and blacks. At SFGH, 44% had a diagnosis of CRC within 1 year of establishing care there. Of those who had established care at SFGH for at least 1 year, only 22% had exposure to CRC screening tests. CONCLUSIONS: These findings allow examination of CRC presentation by ethnicity in vulnerable populations and identify areas where access and utilization of CRC screening can be improved.


Asunto(s)
Neoplasias Colorrectales/diagnóstico , Anciano , Estudios de Cohortes , Neoplasias Colorrectales/etnología , Neoplasias Colorrectales/mortalidad , Detección Precoz del Cáncer , Etnicidad/estadística & datos numéricos , Femenino , Servicios de Salud/estadística & datos numéricos , Humanos , Estimación de Kaplan-Meier , Masculino , Pacientes no Asegurados/estadística & datos numéricos , Persona de Mediana Edad , Estadificación de Neoplasias , Modelos de Riesgos Proporcionales , Programa de VERF , San Francisco , Tasa de Supervivencia , Poblaciones Vulnerables
13.
BMC Gastroenterol ; 12: 79, 2012 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-22734919

RESUMEN

BACKGROUND: Studies document increasing rates of hospitalization among patients with inflammatory bowel disease, but temporal trends for in-hospital mortality among patients with inflammatory bowel disease are not characterized. We sought to determine whether in-hospital mortality changed over a 13-year period among nationwide hospitalizations associated with inflammatory bowel disease. We additionally sought to identify factors correlated with mortality. METHODS: We used the National Hospital Discharge Survey, a large nationally representative database, for the years 1994 through 2006. Age- and mortality-adjusted rates of in-hospital mortality and standardized mortality ratios were calculated for four time periods. Logistic regression analysis was used to assess associations between advancing time and mortality in adjusted analyses. RESULTS: 150 (0.9%) of 17,393 hospitalizations for patients with inflammatory bowel disease ended in death. Age-adjusted in-hospital mortality decreased from 3.6 deaths per 1,000 hospital days in 1994-96 to 2.4 per 1,000 in 2003-06; standardized mortality ratio decreased from 0.33 to 0.27. Similar trends were seen for patients with ulcerative colitis, but mortality did not change over time among patients with Crohn's disease. Multivariable logistic regression analysis confirmed the significance of these changes in mortality, with 17% decreased odds of in-hospital death per three-year period (P=0.012). Subject age (OR 1.06 per year, P<0.001), Charlson comorbidity index (OR 1.29 per 1-point increase, P<0.001), and diagnosis of ulcerative colitis (versus Crohn's disease, OR 1.41, P= .042) were also associated with in-hospital mortality. CONCLUSIONS: The odds of in-hospital mortality among hospitalized patients with inflammatory bowel disease decreased by 17% per 3-year period from 1994 to 2006 in analysis adjusted for age and comorbidity status, in this large, nationally representative database. Multiple factors likely contribute to these trends.


Asunto(s)
Mortalidad Hospitalaria/tendencias , Enfermedades Inflamatorias del Intestino/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Colitis Ulcerosa/mortalidad , Enfermedad de Crohn/mortalidad , Recolección de Datos , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad
14.
Ann Intern Med ; 154(1): 63-4, 2011 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-21200042

RESUMEN

To achieve the benefits of the patient-centered medical home (PCMH) model, the American College of Physicians has issued a policy paper addressing the relationship between specialist and subspecialist physicians and PCMH practices. This paper represents a significant step toward improving care coordination and quality by demonstrating that this model is supported by numerous specialties and subspecialties, recognizing the importance of building a strong medical neighborhood, and providing a framework that will foster improvements in care at the interface of PCMHs and PCMH neighbors (PCMH-Ns). Construction of a well-functioning medical neighborhood will, however, require some refinements. First, the proposed interaction typology between PCMHs and PCMH-Ns must be expanded to include innovative forms of interaction that do not depend on traditional office visits, but for which there are clear incentives. Second, the recommended care coordination agreements must be better standardized for the sake of practicality. Finally, genuine dialogue between PCMH and PCMH-N practices needs to be realized.


Asunto(s)
Actitud del Personal de Salud , Atención a la Salud/organización & administración , Atención Dirigida al Paciente/organización & administración , Atención Primaria de Salud/organización & administración , Especialización , Manejo de Caso/organización & administración , Manejo de Caso/normas , Atención a la Salud/normas , Humanos , Comunicación Interdisciplinaria , Atención Dirigida al Paciente/normas , Atención Primaria de Salud/normas , Estados Unidos
15.
J Am Med Inform Assoc ; 29(4): 694-700, 2022 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-35289368

RESUMEN

While much is known about governance models for research informatics programs in academic medical centers and similarly situated cancer centers, community and public health systems have been less well-characterized. As part of implementing an enterprise research governance framework, leaders in the Los Angeles County Department of Health Services established a research informatics program, including research data warehousing. The strategy is focused on high-priority, patient-centered research that leverages the investment in health IT and an efficient, sustained contribution from 2 affiliated Clinical Translational Sciences Institutes. This case study describes the foundational governance framework and policies that were developed. We share the results of several years of planning, implementation, and operations of an academically funded research informatics service core embedded in a large, multicenter county health system. We include herein a Supplementary Appendix of governance documents that may serve as pragmatic models for similar initiatives.


Asunto(s)
Atención a la Salud , Informática , Centros Médicos Académicos , Data Warehousing , Humanos
17.
J Virol ; 84(21): 11020-9, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20719952

RESUMEN

A small percentage of human immunodeficiency virus (HIV)-infected individuals, termed elite controllers, are able to spontaneously control HIV replication in blood. As the gastrointestinal mucosa is an important site of HIV transmission and replication as well as CD4+ T-cell depletion, it is important to understand the nature of the immune responses occurring in this compartment. Although the role of the HIV-specific CD8+ T-cell responses in mucosal tissues has been described, few studies have investigated the role of mucosal HIV-specific CD4+ T cells. In this study, we assessed HIV-specific CD4+ T-cell responses in the rectal mucosa of 28 "controllers" (viral load [VL] of <2,000 copies/ml), 14 "noncontrollers" (VL of >10,000 copies/ml), and 10 individuals on highly active antiretroviral therapy (HAART) (VL of <75 copies/ml). Controllers had higher-magnitude Gag-specific mucosal CD4+ T-cell responses than individuals on HAART (P<0.05), as measured by their ability to produce gamma interferon (IFN-γ), interleukin-2 (IL-2), tumor necrosis factor alpha (TNF-α), and macrophage inflammatory protein 1ß (MIP-1ß). The frequency of polyfunctional mucosal CD4+ T cells was also higher in controllers than in noncontrollers or individuals on HAART (P<0.05). Controllers with the strongest HIV-specific CD4+ T-cell responses possessed class II HLA alleles, HLA-DRB1*13 and/or HLA-DQB1*06, previously associated with a nonprogression phenotype. Strikingly, individuals with both HLA-DRB1*13 and HLA-DQB1*06 had highly polyfunctional mucosal CD4+ T cells compared to individuals with HLA-DQB1*06 alone or other class II alleles. The frequency of polyfunctional CD4+ T cells in rectal mucosa positively correlated with the magnitude of the mucosal CD8+ T-cell response (Spearman's r=0.43, P=0.005), suggesting that increased CD4+ T-cell "help" may be important in maintaining strong CD8+ T-cell responses in the gut of HIV controllers.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Sobrevivientes de VIH a Largo Plazo , VIH/inmunología , Antígenos HLA-DQ/inmunología , Mucosa Intestinal/inmunología , Terapia Antirretroviral Altamente Activa , Linfocitos T CD4-Positivos/virología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/virología , Citocinas/biosíntesis , Productos del Gen gag/inmunología , Cadenas beta de HLA-DQ , Antígenos HLA-DR , Cadenas HLA-DRB1 , Mucosa Intestinal/virología , Fenotipo
18.
J Virol ; 84(19): 10354-65, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20668079

RESUMEN

Previous studies have suggested that polyfunctional mucosal CD8(+) T-cell responses may be a correlate of protection in HIV controllers. Mucosal T-cell breadth and/or specificity may also contribute to defining protective responses. In this study, rectal CD8(+) T-cell responses to HIV Gag, Env, and Nef were mapped at the peptide level in four subject groups: elite controllers (n = 16; viral load [VL], <75 copies/ml), viremic controllers (n = 14; VL, 75 to 2,000 copies/ml), noncontrollers (n = 14; VL, >10,000 copies/ml), and antiretroviral-drug-treated subjects (n = 8; VL, <75 copies/ml). In all subject groups, immunodominant CD8(+) T-cell responses were generally shared by blood and mucosa, although there were exceptions. In HIV controllers, responses to HLA-B27- and HLA-B57-restricted epitopes were common to both tissues, and their magnitude (in spot-forming cells [SFC] per million) was significantly greater than those of responses restricted by other alleles. Furthermore, peptides recognized by T cells in both blood and rectal mucosa, termed "concordant," elicited higher median numbers of SFC than discordant responses. In magnitude as well as breadth, HIV Gag-specific responses, particularly those targeting p24 and p7, dominated in controllers. Responses in noncontrollers were more evenly distributed among epitopes in Gag, Env, and Nef. Viremic controllers showed significantly broader mucosal Gag-specific responses than other groups. Taken together, these findings demonstrate that (i) Gag-specific responses dominate in mucosal tissues of HIV controllers; (ii) there is extensive overlap between CD8(+) T cells in blood and mucosal tissues, with responses to immunodominant epitopes generally shared by both sites; and (iii) mucosal T-cell response breadth alone cannot account for immune control.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Sobrevivientes de VIH a Largo Plazo , VIH-1 , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/inmunología , Terapia Antirretroviral Altamente Activa , Femenino , Antígenos VIH , Infecciones por VIH/sangre , Infecciones por VIH/tratamiento farmacológico , VIH-1/inmunología , Antígenos HLA-B , Antígeno HLA-B27 , Interacciones Huésped-Patógeno/inmunología , Humanos , Inmunidad Mucosa , Epítopos Inmunodominantes , Mucosa Intestinal/inmunología , Mucosa Intestinal/virología , Masculino , Recto/inmunología , Recto/virología , Carga Viral , Productos del Gen env del Virus de la Inmunodeficiencia Humana/inmunología , Productos del Gen nef del Virus de la Inmunodeficiencia Humana/inmunología
19.
Blood ; 113(17): 3978-89, 2009 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-19109229

RESUMEN

There exists a unique group of persons who are able to durably control HIV in the absence of therapy. The mechanisms of control in these persons remain poorly defined. In this study, we examined CD8(+) T-cell responses in blood and rectal mucosa from 17 "elite controllers" (viral load < 75 copies/mL), 11 "viremic controllers" (75-2000 copies/mL), 14 noncontrollers (> 10,000 copies/mL), and 10 antiretroviral-treated persons (< 75 copies/mL). Production of interferon-gamma, interleukin-2, tumor necrosis factor-alpha, macrophage inflammatory protein-1 beta, and CD107a by CD8(+) T cells in response to HIV-1 Gag stimulation was measured using flow cytometry. Our hypothesis was that "polyfunctional" T cells producing multiple antiviral factors would be most abundant in mucosal tissues of HIV controllers. Mucosal CD8(+) T-cell responses were significantly stronger and more complex in controllers than in antiretroviral-suppressed persons (P = .0004). The frequency of 4-function responses in rectal mucosa was higher in controllers than in noncontrollers and patients on therapy (P < .0001). Mucosal responses in controllers were frequently stronger and more complex than blood responses. These findings demonstrate that many controllers mount strong, complex HIV-specific T-cell responses in rectal mucosa. These responses may play an important role in mucosal immune surveillance, as suggested by their relative enrichment among persons who control HIV in the absence of therapy.


Asunto(s)
Infecciones por VIH/inmunología , VIH-1/inmunología , Biopsia , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/patología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Estudios de Casos y Controles , Recuento de Células , Quimiocina CCL4/biosíntesis , Quimiocina CCL4/inmunología , Femenino , Productos del Gen gag/inmunología , Genotipo , Infecciones por VIH/patología , Infecciones por VIH/cirugía , Salud , Antígenos de Histocompatibilidad Clase I/genética , Antígenos de Histocompatibilidad Clase I/inmunología , Humanos , Inmunidad Mucosa/inmunología , Interferón gamma/inmunología , Masculino , Recto/inmunología , Factor de Necrosis Tumoral alfa/inmunología
20.
Dig Dis Sci ; 56(1): 213-9, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20972850

RESUMEN

BACKGROUND: Hepatitis C (HCV) knowledge is limited in injection drug users (IDU). Vulnerable populations including IDUs are disproportionally affected by HCV. Effective HCV education can potentially reduce disparity in HCV prevalence and its outcome in this population. AIM: This study aimed to assess the impact of formal HCV education and factors associated with improved HCV knowledge in the vulnerable population. METHODS: Over 18 months, 201 HCV-infected patients underwent a 2-h standardized education and completed demographic and pre- and post-education questionnaires. RESULTS: Patient characteristics were: 69% male, mean age 49±10, 49% White (26% AA, 10% Latino), 75% unemployed, 83% high school education and above, 64% were IDU, and 7% were HIV co-infected. On multivariate analysis, baseline knowledge scores were higher in patients with at least a high school education (coef 7.1, p=0.045). Baseline knowledge scores were lower in African Americans (coef -12.3, p=0.004) and older patients (coef -0.7, p=0.03). Following HCV education, the overall test scores improved significantly by 14% (p=0.0001) specifically in the areas of HCV transmission (p=0.003), general knowledge (p=0.02), and health care maintenance (p=0.004). There was a high compliance with liver specialty clinic attendance following education. CONCLUSIONS: Formal HCV education is effective in improving HCV knowledge. Although White race, younger age, and higher education were predictors of having more HCV knowledge prior to education, all patients independent of racial background had a significant improvement in their knowledge after education. Therefore, promoting effective HCV education among vulnerable populations may be an important factor in reducing the disparities in HCV disease.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Hepatitis C/epidemiología , Hepatitis C/prevención & control , Educación del Paciente como Asunto , Adulto , Negro o Afroamericano/etnología , Femenino , Hepatitis C/etnología , Hispánicos o Latinos/etnología , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Prevalencia , Estudios Prospectivos , Encuestas y Cuestionarios , Población Blanca/etnología
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