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1.
J Ment Health Policy Econ ; 20(1): 21-36, 2017 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-28418835

RESUMEN

BACKGROUND: Between 1990 and 2006 in Birmingham, Alabama USA, 4 separate randomized controlled studies, called "Homeless 1" through "Homeless 4", treated cocaine substance abuse among chronically homeless adults, largely black men, many with non-psychotic mental health problems. The 4 studies had 9 treatment arms that used various counseling methods plus, in some arms, the provision of housing and work therapy usually with a contingent requirement of urine-test verified abstinence from substances. Participants in the abstinent-contingent arms who lapsed on abstinence were removed from housing and sent to an evening public shelter from which they were daily transported to day treatment until they returned to abstinence. AIMS OF THE STUDY: This paper compares the cost effectiveness of the treatment arms. METHODS: Societal cost per participant (in 2014 dollars) for each arm is defined as direct treatment cost plus cost of jail or hospital plus societal expense of public shelter use by lapsed participants. An untreated Base Case is defined as 5 percent abstinence with 95 percent usage of a public shelter. Incremental Cost Effectiveness Ratios (ICERs) for paired arms are defined as the change in cost per participant divided by the change in abstinence. Bootstrapping estimates confidence intervals. RESULTS: Average cost per participant at the end of 6 months of active treatment in 7 arms with comparable data ranged from USD 10,447 to USD 36,194 with corresponding average weeks abstinent ranging from 6.1 to 15.3 out of a possible 26 weeks. In contrast, the Base Case would cost USD 6,123 for 1.3 weeks of abstinence. Compared to the Base Case, the least expensive "DT2" treatment has an ICER of USD 901 (95% CI = USD 571 to USD 1,681) per additional week of abstinence and the most expensive "CMP4" has an ICER of USD 2,147 (95% CI = USD 1,701 to USD 2,848). Additionally, the Homeless 3 study found that the abstinent contingent housing (ACH3) treatment compared to the Non Abstinent Contingent Housing (NAC3), analogous to "Housing First", achieved better abstinence (12.1 v. 10 weeks) at higher average cost (USD 22,512 v. USD 17,541) yielding an ICER for this comparison of (USD 2,367, 95% CI=USD -10,587 to USD 12,467). Similar results are found at 12 months (6 months after active treatment). DISCUSSION: More intensive methods of counseling improved abstinence but 4 of the 7 treatments were inefficient ("dominated"). Bootstrapping shows that results are sensitive to which individuals were randomly assigned to each arm. A limitation of the analysis is that it does not consider the full societal cost of lost wages, crime costs beyond jail expenses and deterioration of neighborhood quality of life. Additionally, populations treated by Housing First programs may differ from the Birmingham Homeless studies in the severity of addiction or co-occuring psychological problems. IMPLICATIONS FOR TREATMENT: The Homeless studies show that abstinent contingent safe housing with counseling can substantially improve abstinence for homeless cocaine abusers. Incremental costs rise sharply with more intensive counseling; modest programs of counseling may be more cost effective in a stepped treatment strategy.


Asunto(s)
Trastornos Relacionados con Cocaína/economía , Trastornos Relacionados con Cocaína/terapia , Análisis Costo-Beneficio/economía , Consejo/economía , Personas con Mala Vivienda , Evaluación de Programas y Proyectos de Salud/economía , Adulto , Alabama , Análisis Costo-Beneficio/estadística & datos numéricos , Consejo/métodos , Consejo/estadística & datos numéricos , Empleo/economía , Empleo/métodos , Empleo/estadística & datos numéricos , Femenino , Vivienda/economía , Vivienda/estadística & datos numéricos , Humanos , Masculino , Evaluación de Programas y Proyectos de Salud/métodos , Evaluación de Programas y Proyectos de Salud/estadística & datos numéricos
2.
J Environ Sci (China) ; 43: 15-25, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27155405

RESUMEN

Switchgrass (Panicum virgatum L.) is a perennial C4 grass native to North America and successfully adapted to diverse environmental conditions. It offers the potential to reduce soil surface carbon dioxide (CO2) fluxes and mitigate climate change. However, information on how these CO2 fluxes respond to changing climate is still lacking. In this study, CO2 fluxes were monitored continuously from 2011 through 2014 using high frequency measurements from Switchgrass land seeded in 2008 on an experimental site that has been previously used for soybean (Glycine max L.) in South Dakota, USA. DAYCENT, a process-based model, was used to simulate CO2 fluxes. An improved methodology CPTE [Combining Parameter estimation (PEST) with "Trial and Error" method] was used to calibrate DAYCENT. The calibrated DAYCENT model was used for simulating future CO2 emissions based on different climate change scenarios. This study showed that: (i) the measured soil CO2 fluxes from Switchgrass land were higher for 2012 which was a drought year, and these fluxes when simulated using DAYCENT for long-term (2015-2070) provided a pattern of polynomial curve; (ii) the simulated CO2 fluxes provided different patterns with temperature and precipitation changes in a long-term, (iii) the future CO2 fluxes from Switchgrass land under different changing climate scenarios were not significantly different, therefore, it can be concluded that Switchgrass grown for longer durations could reduce changes in CO2 fluxes from soil as a result of temperature and precipitation changes to some extent.


Asunto(s)
Dióxido de Carbono/análisis , Monitoreo del Ambiente/métodos , Panicum/fisiología , Contaminantes del Suelo/análisis , Suelo/química , Agricultura , Cambio Climático , Modelos Químicos , Lluvia , Temperatura
3.
J Gen Intern Med ; 29 Suppl 4: 835-44, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25355085

RESUMEN

BACKGROUND: While most organizational literature has focused on initiatives that transpire inside the hospital walls, the redesign of American health care increasingly asks that health care institutions address matters outside their walls, targeting the health of populations. The US Department of Veterans Affairs (VA)'s national effort to end Veteran homelessness represents an externally focused organizational endeavor. OBJECTIVE: Our aim was to evaluate the role of organizational practices in the implementation of Housing First (HF), an evidence-based homeless intervention for chronically homeless individuals. DESIGN: This was an interview-based comparative case study conducted across eight VA Medical Centers (VAMCs). PARTICIPANTS: Front line staff, mid-level managers, and senior leaders at VA Medical Centers were interviewed between February and December 2012. APPROACH: Using a structured narrative and numeric scoring, we assessed the correlation between successful HF implementation and organizational practices devised according to the organizational transformation model (OTM). KEY RESULTS: Scoring results suggested a strong association between HF implementation and OTM practice. Strong impetus to house Veterans came from national leadership, reinforced by Medical Center directors closely tracking results. More effective Medical Center leaders differentiated themselves by joining front-line staff in the work (at public events and in process improvement exercises), by elevating homeless-knowledgeable persons into senior leadership, and by exerting themselves to resolve logistic challenges. Vertical alignment and horizontal integration advanced at sites that fostered work groups cutting across service lines and hierarchical levels. By contrast, weak alignment from top to bottom typically also hindered cooperation across departments. Staff commitment to ending homelessness was high, though sustainability planning was limited in this baseline year of observation. CONCLUSION: Key organizational practices correlated with more successful implementation of HF for homeless Veterans. Medical Center directors substantively influenced the success of this endeavor through their actions to foster impetus, demonstrate commitment and support alignment and integration.


Asunto(s)
Vivienda , Personas con Mala Vivienda , Liderazgo , United States Department of Veterans Affairs/organización & administración , Conducta Cooperativa , Humanos , Modelos Organizacionales , Innovación Organizacional , Investigación Cualitativa , Estados Unidos , Veteranos/estadística & datos numéricos
4.
AIDS Care ; 26(5): 574-81, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24116662

RESUMEN

Declines in HIV care and treatment adherence among HIV-infected women from pregnancy to the postpartum period have significant implications for the clinical outcomes and overall well-being of HIV-infected women, especially due to immunosuppression during the postpartum period. While the overall increased risk for mortality associated with HIV care discontinuation is well established, the reasons for HIV care nonadherence among HIV-infected postpartum women are largely unknown. Eighteen HIV-infected women were recruited from four clinics in Alabama to participate in focus groups or individual interviews to discuss barriers and facilitators impacting postpartum HIV care adherence. Sessions were audio-recorded, transcribed, and coded; content analysis was used to analyze the verbatim transcripts. Mixed methods analysis procedures were used to triangulate data from three sources (focus group transcripts, individual rankings of barriers and facilitators according to the Nominal Group Technique, and individual questionnaires of sociodemographic and adherence data). The majority of participants were African-American (83.3%), single (66.7%), with more than half of the participants living on less than $1000 a month (55.6%). Barriers to retention in HIV care included access to and cost of transportation and fitting HIV care into work and childcare schedules. Facilitators to HIV care adherence included wanting to stay healthy for their own well-being as well as for the care of their children, receiving family support, and appointment reminders. The current study highlights contextual factors contributing to poor HIV care adherence among HIV-infected postpartum women. Intervention studies need to be cognizant of the specific needs of HIV-infected postpartum women to improve long-term clinical outcomes among this population, who have children.


Asunto(s)
Infecciones por VIH/tratamiento farmacológico , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Centros de Salud Materno-Infantil , Cumplimiento de la Medicación/estadística & datos numéricos , Aceptación de la Atención de Salud/estadística & datos numéricos , Periodo Posparto , Población Rural/estadística & datos numéricos , Adulto , Alabama/epidemiología , Instituciones de Atención Ambulatoria/estadística & datos numéricos , Citas y Horarios , Femenino , Infecciones por VIH/epidemiología , Infecciones por VIH/psicología , Necesidades y Demandas de Servicios de Salud , Humanos , Recién Nacido , Cumplimiento de la Medicación/psicología , Aceptación de la Atención de Salud/psicología , Periodo Posparto/psicología , Embarazo , Relaciones Profesional-Paciente , Investigación Cualitativa , Apoyo Social , Encuestas y Cuestionarios , Transportes
5.
Am J Public Health ; 103(8): 1457-67, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23763417

RESUMEN

OBJECTIVES: The purpose of this study was to better understand substance use behaviors and deleterious health consequences among individuals with HIV. METHODS: We examined a multicenter cohort of HIV-infected patients (n = 3,413) receiving care in 4 US cities (Seattle, Birmingham, San Diego, Boston) between December 2005 and April 2010 in the Centers for AIDS Research Network of Integrated Clinical Systems (CNICS). We used generalized estimating equations to model specific substance use outcomes. RESULTS: Overall, 24% of patients reported recent use of marijuana; 9% reported amphetamine use, 9% reported crack-cocaine use, 2% reported opiate use, 3.8% reported injection drug use, and 10.3% reported polydrug use. In adjusted multivariable models, those who reported unprotected anal sex had higher odds of marijuana, amphetamine, injection drug, and polydrug use. An increased number of distinct vaginal sexual partners was associated with polydrug and crack-cocaine use. Nonadherence to antiretroviral therapy was associated with the use of all substances other than marijuana. CONCLUSIONS: The co-occurrence of substance use, unprotected intercourse, and medication nonadherence could attenuate the public health benefits of test, treat, and link to care strategies. Prevention programs are needed that address these coprevalent conditions.


Asunto(s)
Infecciones por VIH/epidemiología , Atención Primaria de Salud , Trastornos Relacionados con Sustancias/epidemiología , Adulto , Alabama/epidemiología , California/epidemiología , Estudios de Cohortes , Femenino , Infecciones por VIH/tratamiento farmacológico , Humanos , Masculino , Massachusetts/epidemiología , Persona de Mediana Edad , Análisis Multivariante , Cooperación del Paciente/estadística & datos numéricos , Conducta Sexual , Parejas Sexuales , Estados Unidos/epidemiología , Washingtón/epidemiología
6.
AIDS Behav ; 17(8): 2781-91, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23086427

RESUMEN

This study described characteristics, psychiatric diagnoses and response to treatment among patients in an outpatient HIV clinic who screened positive for depression. Depressed (25 %) were less likely to have private insurance, less likely to have suppressed HIV viral loads, had more anxiety symptoms, and were more likely to report current substance abuse than not depressed. Among depressed, 81.2 % met diagnostic criteria for a depressive disorder; 78 % for an anxiety disorder; 61 % for a substance use disorder; and 30 % for co-morbid anxiety, depression, and substance use disorders. Depressed received significantly more treatment for depression and less HIV primary care than not depressed patients. PHQ-9 total depression scores decreased by 0.63 from baseline to 6-month follow-up for every additional attended depression treatment visit. HIV clinics can routinely screen and treat depressive symptoms, but should consider accurate psychiatric diagnosis as well as co-occurring mental disorders.


Asunto(s)
Ansiedad/epidemiología , Depresión/epidemiología , Infecciones por VIH/epidemiología , Infecciones por VIH/psicología , Tamizaje Masivo , Atención Primaria de Salud , Aislamiento Social/psicología , Trastornos Relacionados con Sustancias/epidemiología , Adulto , Alabama/epidemiología , Ansiedad/diagnóstico , Recuento de Linfocito CD4 , Comorbilidad , Depresión/diagnóstico , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estigma Social , Trastornos Relacionados con Sustancias/diagnóstico , Encuestas y Cuestionarios , Población Urbana , Carga Viral
7.
J Neurosci ; 31(10): 3828-42, 2011 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-21389238

RESUMEN

Birdsong is comprised of rich spectral and temporal organization, which might be used for vocal perception. To quantify how this structure could be used, we have reconstructed birdsong spectrograms by combining the spike trains of zebra finch auditory midbrain neurons with information about the correlations present in song. We calculated maximum a posteriori estimates of song spectrograms using a generalized linear model of neuronal responses and a series of prior distributions, each carrying different amounts of statistical information about zebra finch song. We found that spike trains from a population of mesencephalicus lateral dorsalis (MLd) neurons combined with an uncorrelated Gaussian prior can estimate the amplitude envelope of song spectrograms. The same set of responses can be combined with Gaussian priors that have correlations matched to those found across multiple zebra finch songs to yield song spectrograms similar to those presented to the animal. The fidelity of spectrogram reconstructions from MLd responses relies more heavily on prior knowledge of spectral correlations than temporal correlations. However, the best reconstructions combine MLd responses with both spectral and temporal correlations.


Asunto(s)
Mesencéfalo/fisiología , Neuronas/fisiología , Espectrografía del Sonido/métodos , Vocalización Animal/fisiología , Estimulación Acústica , Potenciales de Acción/fisiología , Animales , Electrofisiología , Pinzones , Procesamiento de Señales Asistido por Computador
8.
Clin Infect Dis ; 54(1): 141-7, 2012 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-22042879

RESUMEN

INTRODUCTION: Computerized collection of standardized measures of patient reported outcomes (PROs) provides a novel paradigm for data capture at the point of clinical care. Comparisons between data from PROs and Electronic Health Records (EHR) are lacking. We compare EHR and PRO for capture of depression and substance abuse and their relationship to adherence to antiretroviral therapy (ART). METHODS: This retrospective study includes HIV-positive patients at an HIV clinic who completed an initial PRO assessment April 2008-July 2009. The questionnaire includes measures of depression (PHQ-9) and substance abuse (ASSIST). Self-reported ART adherence was modeled using separate logistic regression analyses (EHR vs PRO). RESULTS: The study included 782 participants. EHR vs PRO diagnosis of current substance abuse was 13% (n = 99) vs 6% (n = 45) (P < .0001), and current depression was 41% (n = 317) vs 12% (n = 97) (P < .0001). In the EHR model, neither substance abuse (OR = 1.25; 95% CI = 0.70-2.21) nor depression (OR = 0.93; 95% CI = 0.62-1.40) was significantly associated with poor ART adherence. Conversely, in the PRO model, current substance abuse (OR = 2.78; 95% CI = 1.33-5.81) and current depression (OR = 1.93; 95% CI = 1.12-3.33) were associated with poor ART adherence. DISCUSSIONS: The explanatory characteristics of the PRO model correlated best with factors known to be associated with poor ART adherence (substance abuse; depression). The computerized capture of PROs as a part of routine clinical care may prove to be a complementary and potentially transformative health informatics technology for research and patient care.


Asunto(s)
Fármacos Anti-VIH/administración & dosificación , Recolección de Datos/métodos , Infecciones por VIH/tratamiento farmacológico , Adulto , Estudios de Cohortes , Estudios Transversales , Depresión/epidemiología , Femenino , Humanos , Masculino , Cumplimiento de la Medicación , Persona de Mediana Edad , Estudios Retrospectivos , Trastornos Relacionados con Sustancias/epidemiología , Encuestas y Cuestionarios , Resultado del Tratamiento
9.
PLoS Pathog ; 6(5): e1000890, 2010 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-20485520

RESUMEN

Elucidating virus-host interactions responsible for HIV-1 transmission is important for advancing HIV-1 prevention strategies. To this end, single genome amplification (SGA) and sequencing of HIV-1 within the context of a model of random virus evolution has made possible for the first time an unambiguous identification of transmitted/founder viruses and a precise estimation of their numbers. Here, we applied this approach to HIV-1 env analyses in a cohort of acutely infected men who have sex with men (MSM) and found that a high proportion (10 of 28; 36%) had been productively infected by more than one virus. In subjects with multivariant transmission, the minimum number of transmitted viruses ranged from 2 to 10 with viral recombination leading to rapid and extensive genetic shuffling among virus lineages. A combined analysis of these results, together with recently published findings based on identical SGA methods in largely heterosexual (HSX) cohorts, revealed a significantly higher frequency of multivariant transmission in MSM than in HSX [19 of 50 subjects (38%) versus 34 of 175 subjects (19%); Fisher's exact p = 0.008]. To further evaluate the SGA strategy for identifying transmitted/founder viruses, we analyzed 239 overlapping 5' and 3' half genome or env-only sequences from plasma viral RNA (vRNA) and blood mononuclear cell DNA in an MSM subject who had a particularly well-documented virus exposure history 3-6 days before symptom onset and 14-17 days before peak plasma viremia (47,600,000 vRNA molecules/ml). All 239 sequences coalesced to a single transmitted/founder virus genome in a time frame consistent with the clinical history, and a molecular clone of this genome encoded replication competent virus in accord with model predictions. Higher multiplicity of HIV-1 infection in MSM compared with HSX is consistent with the demonstrably higher epidemiological risk of virus acquisition in MSM and could indicate a greater challenge for HIV-1 vaccines than previously recognized.


Asunto(s)
Infecciones por VIH , VIH-1/crecimiento & desarrollo , VIH-1/genética , Homosexualidad Masculina/estadística & datos numéricos , Conducta Sexual/estadística & datos numéricos , Brotes de Enfermedades/estadística & datos numéricos , Evolución Molecular , Variación Genética , Genoma Viral , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Infecciones por VIH/transmisión , VIH-1/patogenicidad , Heterosexualidad/estadística & datos numéricos , Humanos , Masculino , Modelos Genéticos , Recombinación Genética/genética , Factores de Riesgo , Virulencia , Productos del Gen env del Virus de la Inmunodeficiencia Humana/genética
10.
J Gen Intern Med ; 27(7): 808-16, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22274889

RESUMEN

BACKGROUND: For adults in general population community settings, data regarding long-term course and outcomes of illicit drug use are sparse, limiting the formulation of evidence-based recommendations for drug use screening of adults in primary care. OBJECTIVE: To describe trajectories of three illicit drugs (cocaine, opioids, amphetamines) among adults in community settings, and to assess their relation to all-cause mortality. DESIGN: Longitudinal cohort, 1987/88-2005/06. SETTING: Community-based recruitment from four cities (Birmingham, Chicago, Oakland, Minneapolis). PARTICIPANTS: Healthy adults, balanced for race (black and white) and gender were assessed for drug use from 1987/88-2005/06, and for mortality through 12/31/2008 (n = 4301) MEASUREMENTS: Use of cocaine, amphetamines, and opioids (last 30 days) was queried in the following years: 1987/88, 1990/91, 1992/93, 1995/96, 2000/01, 2005/06. Survey-based assessment of demographics and psychosocial characteristics. Mortality over 18 years. RESULTS: Trajectory analysis identified four groups: Nonusers (n = 3691, 85.8%), Early Occasional Users (n = 340, 7.9%), Persistent Occasional Users (n = 160, 3.7%), and Early Frequent/Later Occasional Users (n = 110, 2.6%). Trajectories conformed to expected patterns regarding demographics, other substance use, family background and education. Adjusting for demographics, baseline health status, health behaviors (alcohol, tobacco), and psychosocial characteristics, Early Frequent/Later Occasional Users had greater all-cause mortality (Hazard Ratio, HR = 4.94, 95% CI = 1.58-15.51, p = 0.006). LIMITATIONS: Study is restricted to three common drugs, and trajectory analyses represent statistical approximations rather than identifiable "types". Causal inferences are tentative. CONCLUSIONS: Four trajectories describe illicit drug use from young adulthood to middle age. Two trajectories, representing over one third of adult users, continued use into middle age. These persons were more likely to continue harmful risk behaviors such as smoking, and more likely to die.


Asunto(s)
Trastornos Relacionados con Sustancias/mortalidad , Adolescente , Adulto , Factores de Edad , Alcoholismo/mortalidad , Trastornos Relacionados con Anfetaminas/mortalidad , Trastornos Relacionados con Cocaína/mortalidad , Diagnóstico Dual (Psiquiatría) , Femenino , Humanos , Estudios Longitudinales , Masculino , Abuso de Marihuana/mortalidad , Trastornos Mentales/mortalidad , Persona de Mediana Edad , Trastornos Relacionados con Opioides/mortalidad , Pronóstico , Fumar/mortalidad , Estados Unidos/epidemiología , Salud Urbana/estadística & datos numéricos , Adulto Joven
11.
AANA J ; 80(2): 120-8, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22586881

RESUMEN

Abuse and dependency on potent opioids have long been recognized as problems among nurse anesthetists and anesthesiologists. Research has provided insight into the incidence of abuse, risk factors associated with this type of dependency, identification of an impaired provider, treatment for abuse and dependency, and prevention strategies. Although several factors influence the development of abuse and dependency, access to potent opioids likely has a large role. This access also makes returning to practice while in recovery extremely difficult because the temptation for relapse continually surrounds a recovering anesthesia provider. There is research supporting successful reentry of anesthesia providers into the practice of anesthesia; however, research also reveals high relapse rates among anesthesia providers who return to the practice of anesthesia. This article reviews the literature regarding opioid abuse and dependency among nurse anesthetists and anesthesiologists and offers implications for future research.


Asunto(s)
Anestesiología/estadística & datos numéricos , Enfermeras Anestesistas/estadística & datos numéricos , Trastornos Relacionados con Opioides/epidemiología , Inhabilitación Profesional/estadística & datos numéricos , Humanos , Trastornos Relacionados con Opioides/prevención & control , Trastornos Relacionados con Opioides/psicología , Inhabilitación Profesional/psicología , Factores de Riesgo
12.
Curr Biol ; 32(15): 3245-3260.e5, 2022 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-35767997

RESUMEN

Visual discrimination improves with training, a phenomenon that is thought to reflect plastic changes in the responses of neurons in primary visual cortex (V1). However, the identity of the neurons that undergo change, the nature of the changes, and the consequences of these changes for other visual behaviors remain unclear. We used chronic in vivo 2-photon calcium imaging to monitor the responses of neurons in the V1 of tree shrews learning a Go/No-Go fine orientation discrimination task. We observed increases in neural population measures of discriminability for task-relevant stimuli that correlate with performance and depend on a select subset of neurons with preferred orientations that include the rewarded stimulus and nearby orientations biased away from the non-rewarded stimulus. Learning is accompanied by selective enhancement in the response of these neurons to the rewarded stimulus that further increases their ability to discriminate the task stimuli. These changes persist outside of the trained task and predict observed enhancement and impairment in performance of other discriminations, providing evidence for selective and persistent learning-induced plasticity in the V1, with significant consequences for perception.


Asunto(s)
Aprendizaje Discriminativo , Corteza Visual , Animales , Aprendizaje Discriminativo/fisiología , Estimulación Luminosa , Tupaia , Tupaiidae , Corteza Visual/fisiología , Percepción Visual/fisiología
13.
J Neurophysiol ; 106(2): 500-14, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21543752

RESUMEN

The majority of sensory physiology experiments have used anesthesia to facilitate the recording of neural activity. Current techniques allow researchers to study sensory function in the context of varying behavioral states. To reconcile results across multiple behavioral and anesthetic states, it is important to consider how and to what extent anesthesia plays a role in shaping neural response properties. The role of anesthesia has been the subject of much debate, but the extent to which sensory coding properties are altered by anesthesia has yet to be fully defined. In this study we asked how urethane, an anesthetic commonly used for avian and mammalian sensory physiology, affects the coding of complex communication vocalizations (songs) and simple artificial stimuli in the songbird auditory midbrain. We measured spontaneous and song-driven spike rates, spectrotemporal receptive fields, and neural discriminability from responses to songs in single auditory midbrain neurons. In the same neurons, we recorded responses to pure tone stimuli ranging in frequency and intensity. Finally, we assessed the effect of urethane on population-level representations of birdsong. Results showed that intrinsic neural excitability is significantly depressed by urethane but that spectral tuning, single neuron discriminability, and population representations of song do not differ significantly between unanesthetized and anesthetized animals.


Asunto(s)
Anestésicos/farmacología , Percepción Auditiva/fisiología , Discriminación en Psicología/fisiología , Mesencéfalo/fisiología , Neuronas/fisiología , Vocalización Animal/fisiología , Estimulación Acústica/métodos , Potenciales de Acción/efectos de los fármacos , Potenciales de Acción/fisiología , Animales , Percepción Auditiva/efectos de los fármacos , Hidrato de Cloral/farmacología , Discriminación en Psicología/efectos de los fármacos , Pinzones , Sulfato de Magnesio/farmacología , Masculino , Mesencéfalo/efectos de los fármacos , Neuronas/efectos de los fármacos , Pentobarbital/farmacología , Vocalización Animal/efectos de los fármacos
14.
J Virol ; 84(12): 6241-7, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20375173

RESUMEN

Recent studies indicate that sexual transmission of human immunodeficiency virus type 1 (HIV-1) generally results from productive infection by only one virus, a finding attributable to the mucosal barrier. Surprisingly, a recent study of injection drug users (IDUs) from St. Petersburg, Russia, also found most subjects to be acutely infected by a single virus. Here, we show by single-genome amplification and sequencing in a different IDU cohort that 60% of IDU subjects were infected by more than one virus, including one subject who was acutely infected by at least 16 viruses. Multivariant transmission was more common in IDUs than in heterosexuals (60% versus 19%; odds ratio, 6.14; 95% confidence interval [CI], 1.37 to 31.27; P = 0.008). These findings highlight the diversity in HIV-1 infection risks among different IDU cohorts and the challenges faced by vaccines in protecting against this mode of infection.


Asunto(s)
Consumidores de Drogas/estadística & datos numéricos , Variación Genética , Infecciones por VIH/virología , VIH-1/genética , Adolescente , Adulto , Secuencia de Bases , Estudios de Cohortes , Femenino , Genoma Viral , Proteínas gp160 de Envoltorio del VIH/genética , Infecciones por VIH/epidemiología , VIH-1/clasificación , VIH-1/aislamiento & purificación , VIH-1/fisiología , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Federación de Rusia/epidemiología , Análisis de Secuencia de ADN , Adulto Joven
15.
J Gen Intern Med ; 26(7): 745-50, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21465301

RESUMEN

BACKGROUND: Many newly diagnosed patients present to outpatient care with advanced HIV infection. More timely HIV diagnosis and initiation of care has the potential to improve individual health outcomes and has public health implications. OBJECTIVE: To assess temporal trends in late presentation for outpatient HIV medial care as measured by CD4 count <200 cells/mm(3) and the implications on short-term (1-year) mortality. DESIGN: We conducted a cohort study nested in a prospective HIV clinical cohort including patients establishing initial outpatient HIV treatment between 2000-2010. Time series regression analysis evaluated temporal trends in late presentation for care measured by the proportion of patients with a CD4 count <200 cells/mm(3) or an opportunistic infection at enrollment, and also evaluated trends in short-term mortality. PARTICIPANTS: Patients establishing initial outpatient HIV treatment between 2000-2010 at an academic HIV clinic. MAIN MEASURES: The proportion of patients with a CD4 count <200 cells/mm(3) or an opportunistic infection at initial presentation and short-term (1-year) mortality following clinic enrollment. KEY RESULTS: Among 1121 patients, 41% had an initial CD4 count <200 cells/mm(3), 25% had an opportunistic infection and 2.4% died within 1-year of their initial visit. Time series regression analysis demonstrated significant reductions in late presentation for HIV care and decreases in short-term mortality with temporal improvement preceding updated CDC HIV testing recommendations. CONCLUSION: We observed a significant decline in the number of patients presenting for outpatient HIV care with advanced disease, particularly in 2006-2010. A significant trend in improved short-term survival among patients establishing HIV care was also observed, likely related to more timely presentation for outpatient care in more recent years.


Asunto(s)
Atención a la Salud/tendencias , Infecciones por VIH/mortalidad , Pacientes Ambulatorios/estadística & datos numéricos , Adolescente , Adulto , Recuento de Linfocito CD4 , Estudios de Cohortes , Femenino , Infecciones por VIH/diagnóstico , Política de Salud , Humanos , Masculino , Aceptación de la Atención de Salud , Estudios Prospectivos , Sudeste de Estados Unidos , Tasa de Supervivencia , Factores de Tiempo
16.
Qual Life Res ; 20(9): 1349-57, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21409516

RESUMEN

PURPOSE: We provide detailed instructions for analyzing patient-reported outcome (PRO) data collected with an existing (legacy) instrument so that scores can be calibrated to the PRO Measurement Information System (PROMIS) metric. This calibration facilitates migration to computerized adaptive test (CAT) PROMIS data collection, while facilitating research using historical legacy data alongside new PROMIS data. METHODS: A cross-sectional convenience sample (n = 2,178) from the Universities of Washington and Alabama at Birmingham HIV clinics completed the PROMIS short form and Patient Health Questionnaire (PHQ-9) depression symptom measures between August 2008 and December 2009. We calibrated the tests using item response theory. We compared measurement precision of the PHQ-9, the PROMIS short form, and simulated PROMIS CAT. RESULTS: Dimensionality analyses confirmed the PHQ-9 could be calibrated to the PROMIS metric. We provide code used to score the PHQ-9 on the PROMIS metric. The mean standard errors of measurement were 0.49 for the PHQ-9, 0.35 for the PROMIS short form, and 0.37, 0.28, and 0.27 for 3-, 8-, and 9-item-simulated CATs. CONCLUSIONS: The strategy described here facilitated migration from a fixed-format legacy scale to PROMIS CAT administration and may be useful in other settings.


Asunto(s)
Depresión/diagnóstico , Diagnóstico por Computador , Evaluación de la Discapacidad , Encuestas y Cuestionarios , Adulto , Anciano , Alabama , Automatización , Calibración , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida , Washingtón , Pesos y Medidas , Adulto Joven
17.
Clin Infect Dis ; 50(8): 1165-73, 2010 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-20210646

RESUMEN

BACKGROUND: Human immunodeficiency virus (HIV) and AIDS continue to be associated with an underrecognized risk for suicidal ideation, attempted suicide, and completed suicide. Suicidal ideation represents an important predictor for subsequent attempted and completed suicide. We sought to implement routine screening of suicidal ideation and associated conditions using computerized patient-reported outcome (PRO) assessments. METHODS: Two geographically distinct academic HIV primary care clinics enrolled patients who attended scheduled visits from December 2005 through February 2009. Touch-screen, computer-based PRO assessments were implemented into routine clinical care. Substance abuse, alcohol consumption, depression, and anxiety were assessed. The 9-item Patient Health Questionnaire assesses the frequency of suicidal ideation in the preceding 2 weeks. A response of "nearly every day" triggered an automated page to predetermined clinic personnel, who completed more detailed self-harm assessments. RESULTS: Overall, 1216 patients (740 from the University of Alabama at Birmingham and 476 from the University of Washington) completed the initial PRO assessment during the study period. Patients were predominantly white (646 [53%]) and male (959 [79%]), with a mean age (+/- standard deviation) of 44 +/- 10 years. Among surveyed patients, 170 (14%) endorsed some level of suicidal ideation, whereas 33 (3%) admitted suicidal ideation nearly every day. In multivariable analysis, suicidal ideation risk was lower with advancing age (odds ratio [OR], 0.74 per 10 years; 95% confidence interval [CI], 0.58-0.96) and was increased with current substance abuse (OR, 1.88; 95% CI, 1.03-3.44) and more-severe depression (OR, 3.91 for moderate depression [95% CI, 2.12-7.22] and 25.55 for severe depression [95% CI, 12.73-51.30]). DISCUSSION: Suicidal ideation was associated with current substance abuse and depression. The use of novel technologies to incorporate routine self-reported screening for suicidal ideation and other health domains allows for timely detection and intervention for this life-threatening condition.


Asunto(s)
Automatización/métodos , Computadores , Trastorno Depresivo/diagnóstico , Infecciones por VIH/psicología , Prevención del Suicidio , Encuestas y Cuestionarios , Telemedicina/métodos , Adulto , Alabama , Animales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Washingtón
18.
Am J Public Health ; 100(5): 913-8, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19833998

RESUMEN

OBJECTIVES: We examined whether cocaine-dependent homeless persons had stable housing and were employed 6, 12, and 18 months after they entered a randomized controlled trial comparing 2 treatments. METHODS: One group (n = 103) received abstinence-contingent housing, vocational training, and work; another group (n = 103) received the same intervention plus cognitive behavioral day treatment. We examined baseline and early treatment variables for association with long-term housing and employment. RESULTS: Although the enhanced-treatment group achieved better abstinence rates, the groups did not differ in long-term housing and employment stability. However, consecutive weeks of abstinence during treatment (and to a lesser extent, older age and male gender) predicted long-term housing and employment stability after adjustment for baseline differences in employment, housing, and treatment. CONCLUSIONS: Our data showed a relationship of abstinence with housing stability. Contrasting these results with the increasingly popular Housing First interventions reveals important gaps in our knowledge to be addressed in future research.


Asunto(s)
Trastornos Relacionados con Cocaína/terapia , Empleo , Vivienda , Personas con Mala Vivienda , Cooperación del Paciente , Adulto , Alabama , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo , Resultado del Tratamiento
19.
AIDS Care ; 22(3): 348-54, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20390515

RESUMEN

Substance abuse treatment (SAT) is important for HIV medical care. Characteristics of those who choose SAT and effects of SAT on HIV clinical outcomes are not understood. We compared patients who enrolled and did not enroll in a SAT program offered within an HIV clinic, and evaluated the effect of SAT on CD4 T-cell counts and HIV plasma viral load (VL). Subjects were assessed and invited to enroll in SAT. Enrollees chose to receive psychological and psychiatric treatment, or motivational enhancement and relapse prevention, or residential SAT. We used logistic regressions to determine factors associated with enrollment (age, race, sex, HIV transmission risk factors, CD4 T-cell counts, and VL at assessment). A two-period (assessment and six months after SAT) data analysis was used to analyze the effect of SAT on CD4 T-cell count and log VL controlling for changes in HIV therapy. We find that, compared to Decliners (N=76), Enrollees (N=78) were more likely to be females (29.5% vs. 6.6%, OR=5.32, 95% CI 1.61-17.6), and to report injection drug use (IDU) as the HIV transmission risk factor (23.1% vs. 9.2%, OR=3.92, CI 1.38-11.1). Age (37.2 vs. 38.4), CD4 T-cell count (377.3 vs. 409.2), and log VL (3.21 vs. 2.99) at assessment were similar across the two groups (p>0.05). After six months, Enrollees and Decliners' CD4 T-cell counts increased and log VL decreased. SAT did not affect the change in CD4 T-cell count (p=0.51) or log VL (p=0.73). Similar results were found for patients with CD4 T-cell count < or =350 at assessment. In this small sample of HIV-infected patients with a limited follow-up period, women were more likely to enroll in SAT than men, and SAT reached those who needed it, e.g., IDUs. We did not find an effect of SAT on HIV clinical outcomes.


Asunto(s)
Centros Comunitarios de Salud/estadística & datos numéricos , Infecciones por VIH/tratamiento farmacológico , Aceptación de la Atención de Salud/estadística & datos numéricos , Trastornos Relacionados con Sustancias/terapia , Servicios Urbanos de Salud/estadística & datos numéricos , Adulto , Negro o Afroamericano , Antirretrovirales/uso terapéutico , Recuento de Linfocito CD4 , Comorbilidad , Femenino , Infecciones por VIH/epidemiología , Infecciones por VIH/transmisión , Homosexualidad Masculina , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Aceptación de la Atención de Salud/psicología , Factores de Riesgo , Factores Sexuales , Abuso de Sustancias por Vía Intravenosa/terapia , Abuso de Sustancias por Vía Intravenosa/virología , Trastornos Relacionados con Sustancias/epidemiología , Resultado del Tratamiento , Carga Viral , Adulto Joven
20.
Milbank Q ; 87(2): 495-534, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19523126

RESUMEN

CONTEXT: More than 350 communities in the United States have committed to ending chronic homelessness. One nationally prominent approach, Housing First, offers early access to permanent housing without requiring completion of treatment or, for clients with addiction, proof of sobriety. METHODS: This article reviews studies of Housing First and more traditional rehabilitative (e.g., "linear") recovery interventions, focusing on the outcomes obtained by both approaches for homeless individuals with addictive disorders. FINDINGS: According to reviews of comparative trials and case series reports, Housing First reports document excellent housing retention, despite the limited amount of data pertaining to homeless clients with active and severe addiction. Several linear programs cite reductions in addiction severity but have shortcomings in long-term housing success and retention. CONCLUSIONS: This article suggests that the current research data are not sufficient to identify an optimal housing and rehabilitation approach for an important homeless subgroup. The research regarding Housing First and linear approaches can be strengthened in several ways, and policymakers should be cautious about generalizing the results of available Housing First studies to persons with active addiction when they enter housing programs.


Asunto(s)
Personas con Mala Vivienda/estadística & datos numéricos , Vivienda Popular/estadística & datos numéricos , Rehabilitación Vocacional/estadística & datos numéricos , Tratamiento Domiciliario/organización & administración , Trastornos Relacionados con Sustancias/terapia , Conducta Cooperativa , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Necesidades y Demandas de Servicios de Salud/estadística & datos numéricos , Humanos , Relaciones Interinstitucionales , Evaluación de Resultado en la Atención de Salud , Medio Social , Estados Unidos
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