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1.
Arch Phys Med Rehabil ; 105(3): 604-610, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37657530

RESUMEN

Psychologists have been applying neurorehabilitation models of care for many years. These practitioners come from different training backgrounds and use a variety of titles to refer to themselves despite considerable overlap in practice patterns, professional identification, and salary. Titles like 'neurorehabilitation psychologist' and 'rehabilitation neuropsychologist' are sometimes used by practitioners in the field to indicate their specialty area, but are not formally recognized by the American Psychological Association, the American Board of Professional Psychology, or by training councils in clinical neuropsychology (CN) or rehabilitation psychology (RP). Neither the CN or RP specialties alone fully address or define the competencies, skill sets, and clinical experiences required to provide high quality, comprehensive neurorehabilitation psychology services across settings. Therefore, irrespective of practice setting, we believe that both clinical neuropsychologists and rehabilitation psychologists should ideally have mastery of specific, overlapping competencies and a philosophical approach to care that we call neurorehabilitation psychology in this paper. Trainees and early career professionals who aspire to practice in this arena are often pressured to prioritize either CN or RP pathways over the other, with anxiety about perceived and real potential for falling short in their training goals. In the absence of an explicit training path or formal guidelines, these professionals emerge only after the opportunity, privilege, or frank luck of working with specific mentors or in exceptional patient care settings that lend themselves to obtaining integrated competencies in neurorehabilitation psychology. This paper reflects the efforts of 7 practitioners to preliminarily define the practice and philosophies of neurorehabilitation psychology, the skill sets and competencies deemed essential for best practice, and essential training pathway elements. We propose competencies designed to maximize the integrity of training and provide clear guideposts for professional development.


Asunto(s)
Rehabilitación Neurológica , Humanos , Ansiedad , Mentores , Presión , Salarios y Beneficios
2.
Elife ; 122023 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-37227428

RESUMEN

Background: Dog-mediated rabies is endemic across Africa causing thousands of human deaths annually. A One Health approach to rabies is advocated, comprising emergency post-exposure vaccination of bite victims and mass dog vaccination to break the transmission cycle. However, the impacts and cost-effectiveness of these components are difficult to disentangle. Methods: We combined contact tracing with whole-genome sequencing to track rabies transmission in the animal reservoir and spillover risk to humans from 2010 to 2020, investigating how the components of a One Health approach reduced the disease burden and eliminated rabies from Pemba Island, Tanzania. With the resulting high-resolution spatiotemporal and genomic data, we inferred transmission chains and estimated case detection. Using a decision tree model, we quantified the public health burden and evaluated the impact and cost-effectiveness of interventions over a 10-year time horizon. Results: We resolved five transmission chains co-circulating on Pemba from 2010 that were all eliminated by May 2014. During this period, rabid dogs, human rabies exposures and deaths all progressively declined following initiation and improved implementation of annual islandwide dog vaccination. We identified two introductions to Pemba in late 2016 that seeded re-emergence after dog vaccination had lapsed. The ensuing outbreak was eliminated in October 2018 through reinstated islandwide dog vaccination. While post-exposure vaccines were projected to be highly cost-effective ($256 per death averted), only dog vaccination interrupts transmission. A combined One Health approach of routine annual dog vaccination together with free post-exposure vaccines for bite victims, rapidly eliminates rabies, is highly cost-effective ($1657 per death averted) and by maintaining rabies freedom prevents over 30 families from suffering traumatic rabid dog bites annually on Pemba island. Conclusions: A One Health approach underpinned by dog vaccination is an efficient, cost-effective, equitable, and feasible approach to rabies elimination, but needs scaling up across connected populations to sustain the benefits of elimination, as seen on Pemba, and for similar progress to be achieved elsewhere. Funding: Wellcome [207569/Z/17/Z, 095787/Z/11/Z, 103270/Z/13/Z], the UBS Optimus Foundation, the Department of Health and Human Services of the National Institutes of Health [R01AI141712] and the DELTAS Africa Initiative [Afrique One-ASPIRE/DEL-15-008] comprising a donor consortium of the African Academy of Sciences (AAS), Alliance for Accelerating Excellence in Science in Africa (AESA), the New Partnership for Africa's Development Planning and Coordinating (NEPAD) Agency, Wellcome [107753/A/15/Z], Royal Society of Tropical Medicine and Hygiene Small Grant 2017 [GR000892] and the UK government. The rabies elimination demonstration project from 2010-2015 was supported by the Bill & Melinda Gates Foundation [OPP49679]. Whole-genome sequencing was partially supported from APHA by funding from the UK Department for Environment, Food and Rural Affairs (Defra), Scottish government and Welsh government under projects SEV3500 and SE0421.


Asunto(s)
Mordeduras y Picaduras , Enfermedades de los Perros , Vacunas Antirrábicas , Rabia , Perros , Animales , Humanos , Rabia/epidemiología , Rabia/prevención & control , Rabia/veterinaria , Trazado de Contacto , Análisis Costo-Beneficio , Vacunas Antirrábicas/genética , Tanzanía/epidemiología , Genómica , Mordeduras y Picaduras/epidemiología , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/prevención & control
3.
PLoS One ; 17(10): e0274237, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36201473

RESUMEN

OBJECTIVE: To assess baseline characteristics and antithrombotic treatment (ATT) prescription patterns in patients enrolled in the third phase of the GLORIA-AF Registry Program, evaluate predictors of treatment prescription, and compare results with phase II. METHODS: GLORIA-AF is a large, global, prospective registry program, enrolling patients with newly diagnosed nonvalvular atrial fibrillation (AF) at risk of stroke. Patients receiving dabigatran were followed for two years in phase II, and all patients were followed for 3 years in phase III. Phase II started when dabigatran became available; phase III started when the characteristics of patients receiving dabigatran became roughly comparable with those receiving vitamin K antagonists (VKAs). RESULTS: Between 2014 and 2016, 21,241 patients were enrolled in phase III. In total, 82% of patients were prescribed oral anticoagulation ([OAC]; 59.5% novel/nonvitamin K oral anticoagulants [NOACs], 22.7% VKAs). A further 11% of patients were prescribed antiplatelets without OAC and 7% were prescribed no ATT. A high stroke risk was the main driver of OAC prescription. Factors associated with prescription of VKA over NOAC included type of site, region, physician specialty, and impaired kidney function. CONCLUSION: Over the past few years, data from phase III of GLORIA-AF show that OACs have become the standard treatment option, with most newly diagnosed AF patients prescribed a NOAC. However, in some regions a remarkable proportion of patients remain undertreated. In comparison with phase II, more patients received NOACs in phase III while the prescription of VKA decreased. VKAs were preferred over NOACs in patients with impaired kidney function.


Asunto(s)
Fibrilación Atrial , Accidente Cerebrovascular , Administración Oral , Anticoagulantes/efectos adversos , Fibrilación Atrial/inducido químicamente , Fibrilación Atrial/complicaciones , Fibrilación Atrial/tratamiento farmacológico , Dabigatrán/efectos adversos , Fibrinolíticos/efectos adversos , Humanos , Sistema de Registros , Accidente Cerebrovascular/inducido químicamente , Accidente Cerebrovascular/prevención & control , Vitamina K
4.
F1000Res ; 11: 770, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36016994

RESUMEN

Spatial and spatio-temporal data are used in a wide range of fields including environmental, health and social disciplines. Several packages in the statistical software R have been recently developed as clients for various databases to meet the growing demands for easily accessible and reliable spatial data. While documentation on how to use many of these packages exist, there is an increasing need for a one stop repository for tutorials on this information. In this paper, we present  rspatialdata a website that provides a collection of data sources and tutorials on downloading and visualising spatial data using R. The website includes a wide range of datasets including administrative boundaries of countries, Open Street Map data, population, temperature, vegetation, air pollution, and malaria data. The goal of the website is to equip researchers and communities with the tools to engage in spatial data analysis and visualisation so that they can address important local issues, such as estimating air pollution, quantifying disease burdens, and evaluating and monitoring the United Nation's sustainable development goals.


Asunto(s)
Almacenamiento y Recuperación de la Información , Programas Informáticos , Humanos
5.
Rehabil Psychol ; 67(2): 111-119, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35041443

RESUMEN

PURPOSE/OBJECTIVE: To date, there are no published formal surveys of the "state of the field" of Rehabilitation Psychology in terms of education, training, practice patterns, professional identity, and relative salary and income structures for those who identify as Rehabilitation Psychologists. RESEARCH METHOD/DESIGN: In an effort to gather this information, the Practice Committee of APA Division 22 (Rehabilitation Psychology) conducted a convenience-sample survey of its listserv subscribers to obtain a representation of Rehabilitation Psychologists across the United States, and a depiction of the fields in which they work. RESULTS: There were 282 respondents to the survey. Most respondents were female (69%) and worked in hospital/medical facilities (70%). Most worked in urban/suburban areas (96%), with adults (57%), and had a straight salary income structure (78%). Salary was found to be associated with age (p < .001), gender (p < .001), degree (p = .001), board certification status (p < .001), years licensed (p < .001), and Manager/Director position status (p < .001). Salary was not significantly different by region. CONCLUSIONS: Implications regarding the need for advocacy for the roles of Rehabilitation Psychology in health care, promotion of the specialty with consumers, and the development of future professionals are discussed. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Asunto(s)
Renta , Salarios y Beneficios , Adulto , Escolaridad , Femenino , Humanos , Masculino , Psicología , Encuestas y Cuestionarios , Estados Unidos
6.
PLoS One ; 15(5): e0220592, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32469961

RESUMEN

Infectious diseases are often transmitted through local interactions. Yet, both surveillance and control measures are implemented within administrative units. Capturing local transmission processes and spatial coupling between regions from aggregate level data is therefore a technical challenge that can shed light on both theoretical questions and practical decisions. Fox rabies has been eliminated from much of Europe through oral rabies vaccination (ORV) programmes. The European Union (EU) co-finances ORV to maintain rabies freedom in EU member and border states via a cordon sanitaire. Models to capture local transmission dynamics and spatial coupling have immediate application to the planning of these ORV campaigns and to other parts of the world considering oral vaccination. We fitted a hierarchical Bayesian state-space model to data on three decades of fox rabies cases and ORV campaigns from Eastern Germany. Specifically, we find that (i) combining regional spatial coupling and heterogeneous local transmission allows us to capture regional rabies dynamics; (ii) incursions from other regions account for less than 1% of cases, but allow for re-emergence of disease; (iii) herd immunity achieved through bi-annual vaccination campaigns is short-lived due to population turnover. Together, these findings highlight the need for regular and sustained vaccination efforts and our modelling approach can be used to provide strategic guidance for ORV delivery. Moreover, we show that biological understanding can be gained from inference from partially observed data on wildlife disease.


Asunto(s)
Zorros/virología , Programas de Inmunización , Rabia/prevención & control , Animales , Animales Salvajes/virología , Teorema de Bayes , Europa (Continente)/epidemiología , Unión Europea , Alemania/epidemiología , Humanos , Rabia/transmisión , Rabia/virología , Vacunas Antirrábicas/farmacología , Virus de la Rabia/efectos de los fármacos , Virus de la Rabia/patogenicidad
7.
Philos Trans R Soc Lond B Biol Sci ; 374(1776): 20180280, 2019 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-31104608

RESUMEN

Understanding how the spatial deployment of interventions affects elimination time horizons and potential for disease re-emergence has broad application to control programmes targeting human, animal and plant pathogens. We previously developed an epidemiological model that captures the main features of rabies spread and the impacts of vaccination based on detailed records of fox rabies in eastern Germany during the implementation of an oral rabies vaccination (ORV) programme. Here, we use simulations from this fitted model to determine the best vaccination strategy, in terms of spatial placement and timing of ORV efforts, for three epidemiological scenarios representative of current situations in Europe. We found that consecutive and comprehensive twice-yearly vaccinations across all regions rapidly controlled and eliminated rabies and that the autumn campaigns had the greater impact on increasing the probability of elimination. This appears to result from the need to maintain sufficient herd immunity in the face of large birth pulses, as autumn vaccinations reach susceptible juveniles and therefore a larger proportion of the population than spring vaccinations. Incomplete vaccination compromised time to elimination requiring the same or more vaccination effort to meet similar timelines. Our results have important practical implications that could inform policies for rabies containment and elimination in Europe and elsewhere. This article is part of the theme issue 'Modelling infectious disease outbreaks in humans, animals and plants: epidemic forecasting and control'. This theme issue is linked with the earlier issue 'Modelling infectious disease outbreaks in humans, animals and plants: approaches and important themes'.


Asunto(s)
Simulación por Computador , Modelos Biológicos , Vacunas Antirrábicas/inmunología , Rabia/veterinaria , Estaciones del Año , Vacunación/veterinaria , Animales , Animales Salvajes , Rabia/prevención & control , Vacunas Antirrábicas/administración & dosificación , Vacunación/métodos
8.
Brain Imaging Behav ; 12(5): 1229-1238, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29110194

RESUMEN

This study examines white matter microstructure using quantitative tractography diffusion magnetic resonance imaging (qtdMRI) in HIV+ individuals from South Africa who were naïve or early in the initiation of antiretroviral therapy. Fiber bundle length (FBL) metrics, generated from qtdMRI, for whole brain and six white matter tracts of interest (TOI) were assessed for 135 HIV+ and 21 HIV- individuals. The association between FBL metrics, measures of disease burden, and neuropsychological performance were also investigated. Results indicate significantly reduced sum of whole brain fiber bundle lengths (FBL, p < 0.001), but not average whole brain FBL in the HIV+ group compared to the HIV- controls. The HIV+ group exhibited significantly shorter sum of FBL in all six TOIs examined: the anterior thalamic radiation, cingulum bundle, inferior and superior longitudinal fasciculi, inferior frontal occipital fasciculus, and the uncinate fasciculus. Additionally, average FBLs were significantly shorter select TOIs including the inferior longitudinal fasciculus, cingulum bundle, and the anterior thalamic radiation. Shorter whole brain FBL sum metrics were associated with poorer neuropsychological performance, but were not associated with markers of disease burden. Taken together these findings suggest HIV affects white matter architecture primarily through reductions in white matter fiber numbers and, to a lesser degree, the shortening of fibers along a bundle path.


Asunto(s)
Imagen de Difusión Tensora , Infecciones por VIH/diagnóstico por imagen , Sustancia Blanca/diagnóstico por imagen , Adulto , Femenino , Infecciones por VIH/patología , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Fibras Nerviosas Mielínicas/patología , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/patología , Tamaño de los Órganos , Sudáfrica , Sustancia Blanca/patología , Adulto Joven
9.
J Neurovirol ; 23(5): 725-733, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28895090

RESUMEN

The expression of cognitive symptoms associated with HIV varies over time and across individuals. This pattern may reflect transient contextual factors, including the degree of effort exerted by individuals undergoing cognitive testing. The present study examined whether effort corresponds to the expression of persistent HIV-related cognitive impairment among individuals receiving combination antiretroviral therapy (cART). HIV+ individuals (n = 111) averaged 48.2 (14.9) years of age and 13.0 (2.7) years of education and HIV- individuals (n = 92) averaged 34.9 (17.2) years of age and 13.5 (1.9) years of education. Participants completed a neuropsychological battery and a clinically validated measure of effort (Test of Memory Malingering, trial 1). Results revealed that the vast majority of HIV+ (85%) and HIV- (89%) individuals performed above published guidelines for adequate effort. Furthermore, the expression of cognitive impairment in HIV was not related to effort performance. The results were unchanged when examining HIV+ individuals with and without viral suppression. Finally, disability and disability-seeking status, and a proxy measure of apathy did not correspond to effort levels in HIV+ individuals. These findings suggest that variability in the expression of cognitive impairment in the cART era is unlikely to represent overt effort failures or other confounds unrelated to the disease. Persistent cognitive impairment in HIV likely represents historical and/or ongoing disease mechanisms despite otherwise successful treatment.


Asunto(s)
Complejo SIDA Demencia/diagnóstico , Simulación de Enfermedad/psicología , Motivación , Complejo SIDA Demencia/tratamiento farmacológico , Complejo SIDA Demencia/psicología , Adulto , Terapia Antirretroviral Altamente Activa , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas
10.
J Acquir Immune Defic Syndr ; 76(4): 423-430, 2017 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-28796748

RESUMEN

Inflammation occurs after HIV infection and persists, despite highly active antiretroviral therapy (HAART). Diffusion tensor imaging (DTI) measures HIV-associated white matter changes, but can be confounded by inflammation. Currently, the influence of inflammation on white matter integrity in well-controlled HIV+ patients remains unknown. We used diffusion basis spectral imaging (DBSI)-derived cellularity to isolate restricted water diffusion associated with inflammation separated from the anisotropic diffusion associated with axonal integrity. Ninety-two virologically suppressed HIV+ patients on HAART and 66 HIV uninfected (HIV-) controls underwent neuropsychological performance (NP) testing and neuroimaging. NP tests assessed multiple domains (memory, psychomotor speed, and executive functioning). DTI- and DBSI-derived fractional anisotropy (FA) maps were processed with tract-based spatial statistics for comparison between both groups. Cellularity was assessed regarding age, HIV status, and NP. Within the HIV+ cohort, cellularity was compared with clinical (HAART duration) and laboratory measures of disease (eg, CD4 cell current and nadir). NP was similar for both groups. DTI-derived FA was lower in HIV+ compared with HIV- individuals. By contrast, DBSI-derived FA was similar for both groups. Instead, diffuse increases in cellularity were present in HIV+ individuals. Observed changes in cellularity were significantly associated with age, but not NP, in HIV+ individuals. A trend level association was seen between cellularity and HAART duration. Elevated inflammation, measured by cellularity, persists in virologically well-controlled HIV+ individuals. Widespread cellularity changes occur in younger HIV+ individuals and diminish with aging and duration of HAART.


Asunto(s)
Imagen de Difusión Tensora , Encefalitis/diagnóstico por imagen , Encefalitis/virología , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Leucoencefalopatías/diagnóstico por imagen , Carga Viral/efectos de los fármacos , Adulto , Terapia Antirretroviral Altamente Activa , Disfunción Cognitiva/fisiopatología , Disfunción Cognitiva/virología , Femenino , Infecciones por VIH/diagnóstico por imagen , Infecciones por VIH/virología , Humanos , Leucoencefalopatías/virología , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas
11.
Brain Connect ; 7(2): 115-122, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28076974

RESUMEN

Infection with human immunodeficiency virus (HIV) is associated with neuroimaging alterations. However, little is known about the topological organization of whole-brain networks and the corresponding association with cognition. As such, we examined structural whole-brain white matter connectivity patterns and cognitive performance in 29 HIV+ young adults (mean age = 25.9) with limited or no HIV treatment history. HIV+ participants and demographically similar HIV- controls (n = 16) residing in South Africa underwent magnetic resonance imaging (MRI) and neuropsychological testing. Structural network models were constructed using diffusion MRI-based multifiber tractography and T1-weighted MRI-based regional gray matter segmentation. Global network measures included whole-brain structural integration, connection strength, and structural segregation. Cognition was measured using a neuropsychological global deficit score (GDS) as well as individual cognitive domains. Results revealed that HIV+ participants exhibited significant disruptions to whole-brain networks, characterized by weaker structural integration (characteristic path length and efficiency), connection strength, and structural segregation (clustering coefficient) than HIV- controls (p < 0.05). GDSs and performance on learning/recall tasks were negatively correlated with the clustering coefficient (p < 0.05) in HIV+ participants. Results from this study indicate disruption to brain network integrity in treatment-limited HIV+ young adults with corresponding abnormalities in cognitive performance.


Asunto(s)
Mapeo Encefálico , Encéfalo/diagnóstico por imagen , Imagen de Difusión Tensora , Infecciones por VIH/patología , Vías Nerviosas/diagnóstico por imagen , Sustancia Blanca/diagnóstico por imagen , Adulto , Análisis de Varianza , Linfocitos T CD4-Positivos/patología , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Fibras Nerviosas Mielínicas/patología , Vías Nerviosas/patología , Vías Nerviosas/virología , Pruebas Neuropsicológicas , Sustancia Blanca/virología , Adulto Joven
12.
Brain Imaging Behav ; 11(3): 632-639, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26961092

RESUMEN

Recent work using novel neuroimaging methods has revealed shorter white matter fiber bundle length (FBL) in older compared to younger adults. Shorter FBL also corresponds to poorer performance on cognitive measures sensitive to advanced age. However, it is unclear if individual factors such as cognitive reserve (CR) effectively moderate the relationship between FBL and cognitive performance. This study examined CR as a potential moderator of cognitive performance and brain integrity as defined by FBL. Sixty-three healthy adults underwent neuropsychological evaluation and 3T brain magnetic resonance imaging. Cognitive performance was measured using the Repeatable Battery of Assessment of Neuropsychological Status (RBANS). FBL was quantified from tractography tracings of white matter fiber bundles, derived from the diffusion tensor imaging. CR was determined by estimated premorbid IQ. Analyses revealed that lower scores on the RBANS were associated with shorter whole brain FBL (p = 0.04) and lower CR (p = 0.01) CR moderated the relationship between whole brain FBL and RBANS score (p < 0.01). Tract-specific analyses revealed that CR also moderated the association between FBL in the hippocampal segment of the cingulum and RBANS performance (p = 0.03). These results demonstrate that lower cognitive performance on the RBANS is more common with low CR and short FBL. On the contrary, when individuals have high CR, the relationship between FBL and cognitive performance is attenuated. Overall, CR protects older adults against lower cognitive performance despite age-associated reductions in FBL.


Asunto(s)
Encéfalo/patología , Reserva Cognitiva , Envejecimiento Saludable/patología , Envejecimiento Saludable/psicología , Sustancia Blanca/patología , Encéfalo/diagnóstico por imagen , Imagen de Difusión Tensora , Femenino , Humanos , Inteligencia , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Fibras Nerviosas Mielínicas/patología , Pruebas Neuropsicológicas , Análisis de Regresión , Factores Sexuales , Sustancia Blanca/diagnóstico por imagen
13.
J Neurovirol ; 23(2): 319-328, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27913960

RESUMEN

Controversy remains regarding the neurotoxicity of clade C human immunodeficiency virus (HIV-C). When examined in preclinical studies, a cysteine to serine substitution in the C31 dicysteine motif of the HIV-C Tat protein (C31S) results in less severe brain injury compared to other viral clades. By contrast, patient cohort studies identify significant neuropsychological impairment among HIV-C individuals independent of Tat variability. The present study clarified this discrepancy by examining neuroimaging markers of brain integrity among HIV-C individuals with and without the Tat substitution. Thirty-seven HIV-C individuals with the Tat C31S substitution, 109 HIV-C individuals without the Tat substitution (C31C), and 34 HIV- controls underwent 3T structural magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI). Volumes were determined for the caudate, putamen, thalamus, corpus callosum, total gray matter, and total white matter. DTI metrics included fractional anisotropy (FA), radial diffusivity (RD), and axial diffusivity (AD). Tracts of interest included the anterior thalamic radiation (ATR), cingulum bundle (CING), uncinate fasciculus (UNC), and corpus callosum (CC). HIV+ individuals exhibited smaller volumes in subcortical gray matter, total gray matter and total white matter compared to HIV- controls. HIV+ individuals also exhibited DTI abnormalities across multiple tracts compared to HIV- controls. By contrast, neither volumetric nor diffusion indices differed significantly between the Tat C31S and C31C groups. Tat C31S status is not a sufficient biomarker of HIV-related brain integrity in patient populations. Clinical attention directed at brain health is warranted for all HIV+ individuals, independent of Tat C31S or clade C status.


Asunto(s)
Sustitución de Aminoácidos , Imagen de Difusión Tensora/métodos , Infecciones por VIH/diagnóstico por imagen , VIH/genética , Productos del Gen tat del Virus de la Inmunodeficiencia Humana/genética , Adulto , Mapeo Encefálico , Estudios de Casos y Controles , Núcleo Caudado/diagnóstico por imagen , Núcleo Caudado/patología , Núcleo Caudado/virología , Cuerpo Calloso/diagnóstico por imagen , Cuerpo Calloso/patología , Cuerpo Calloso/virología , Imagen de Difusión Tensora/instrumentación , Femenino , Expresión Génica , Variación Genética , Genotipo , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/patología , Sustancia Gris/virología , VIH/patogenicidad , Infecciones por VIH/patología , Infecciones por VIH/virología , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Putamen/diagnóstico por imagen , Putamen/patología , Putamen/virología , Tálamo/diagnóstico por imagen , Tálamo/patología , Tálamo/virología , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Sustancia Blanca/virología
14.
Technol Innov ; 18(1): 21-29, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27721932

RESUMEN

This paper reviews basic methods and recent applications of length-based fiber bundle analysis of cerebral white matter using diffusion magnetic resonance imaging (dMRI). Diffusion weighted imaging (DWI) is a dMRI technique that uses the random motion of water to probe tissue microstructure in the brain. Diffusion tensor imaging (DTI) is an extension of DWI that measures the magnitude and direction of water diffusion in cerebral white matter, using either voxel-based scalar metrics or tractography-based analyses. More recently, quantitative tractography based on diffusion tensor imaging (qtDTI) technology has been developed to help quantify aggregate structural anatomical properties of white matter fiber bundles, including both scalar metrics of bundle diffusion and more complex morphometric properties, such as fiber bundle length (FBL). Unlike traditional scalar diffusion metrics, FBL reflects the direction and curvature of white matter pathways coursing through the brain and is sensitive to changes within the entire tractography model. In this paper, we discuss applications of this approach to date that have provided new insights into brain organization and function. We also discuss opportunities for improving the methodology through more complex anatomical models and potential areas of new application for qtDTI.

15.
J Neurovirol ; 22(1): 93-103, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26306688

RESUMEN

Most studies that have examined neuropsychological impairments associated with human immunodeficiency virus (HIV) have focused on males, yet females represent one of the largest groups of newly infected patients. Further, few studies have examined neuropsychological performance and neuroimaging outcomes among females compared to males in the modern era of highly active anti-retroviral therapy (HAART). The present study investigated neuropsychological performance and brain volumetrics among HIV+ males (n = 93) and females (n = 44) on stable HAART compared to HIV seronegative (HIV-) males (n = 42) and females (n = 49). Results revealed a significant effect of HIV on neuropsychological performance and neuroimaging measures. An effect of gender, independent of HIV status, was also observed for neuroimaging measures but not neuropsychological performance. Additionally, no significant differences in neuropsychological performance or brain volumetrics were seen between HIV+ males and females. No significant interaction was observed between HIV and gender on either neuropsychological or neuroimaging indices. Our results suggest that both HIV+ males and females treated with HAART experience similar outcomes in terms of brain integrity.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Encéfalo/fisiopatología , Trastornos del Conocimiento/fisiopatología , Infecciones por VIH/fisiopatología , ARN Viral/sangre , Anciano , Terapia Antirretroviral Altamente Activa , Encéfalo/virología , Recuento de Linfocito CD4 , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/patología , Linfocitos T CD4-Positivos/virología , Estudios de Casos y Controles , Trastornos del Conocimiento/complicaciones , Trastornos del Conocimiento/tratamiento farmacológico , Trastornos del Conocimiento/virología , Femenino , Neuroimagen Funcional , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , ARN Viral/antagonistas & inhibidores , Carga Viral/efectos de los fármacos
16.
Brain Imaging Behav ; 10(1): 203-11, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25864197

RESUMEN

Aging is associated with microstructural changes in brain tissue that can be visualized using diffusion tensor imaging (DTI). While previous studies have established age-related changes in white matter (WM) diffusion using DTI, the impact of age on gray matter (GM) diffusion remains unclear. The present study utilized DTI metrics of mean diffusivity (MD) to identify age differences in GM/WM microstructure in a sample of healthy older adults (N = 60). A secondary aim was to determine the functional significance of whole-brain GM/WM MD on global cognitive function using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). Participants were divided into three age brackets (ages 50-59, 60-69, and 70+) to examine differences in MD and cognition by decade. MD was examined bilaterally in the frontal, temporal, parietal, and occipital lobes for the primary analyses and an aggregate measure of whole-brain MD was used to test relationships with cognition. Significantly higher MD was observed in bilateral GM of the temporal and parietal lobes, and in right hemisphere WM of the frontal and temporal lobes of older individuals. The most robust differences in MD were between the 50-59 and 70+ age groups. Higher whole-brain GM MD was associated with poorer RBANS performance in the 60-69 age group. Results suggest that aging has a significant and differential impact on GM/WM diffusion in healthy older adults, which may explain a modest degree of cognitive variability at specific time points during older adulthood.


Asunto(s)
Envejecimiento/patología , Encéfalo/diagnóstico por imagen , Sustancia Gris/diagnóstico por imagen , Anciano , Envejecimiento/psicología , Encéfalo/patología , Cognición , Imagen de Difusión por Resonancia Magnética , Imagen de Difusión Tensora , Femenino , Sustancia Gris/patología , Humanos , Masculino , Persona de Mediana Edad , Pruebas Psicológicas
17.
Behav Brain Res ; 296: 85-93, 2016 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-26318936

RESUMEN

The common angiotensinogen (AGT) M268T polymorphism (rs699; historically referred to as M235T) has been identified as a significant risk factor for cerebrovascular pathologies, yet it is unclear if healthy older adults carrying the threonine amino acid variant have a greater risk for white matter damage in specific fiber tracts. Further, the impact of the threonine variant on cognitive function remains unknown. The present study utilized multiple indices of diffusion tensor imaging (DTI) and neuropsychological assessment to examine the integrity of specific white matter tracts and cognition between individuals with homozygous genotypes of M268T (MetMet n=27, ThrThr n=27). Differences in subcortical hyperintensity (SH) volume were also examined between groups. Results indicated that the threonine variant was associated with significantly reduced integrity in the superior longitudinal fasciculus (SLF) and the cingulate gyrus segment of the cingulum bundle (cingulum CG) compared to those with the methionine variant, and poorer cognitive performance on tests of attention/processing speed and language. Despite these associations, integrity of these tracts did not significantly mediate relationships between cognition and genetic status, and SH did not differ significantly between groups. Collectively our results suggest that the threonine variant of M268T is a significant risk factor for abnormalities in specific white matter tracts and cognitive domains in healthy older adults, independent of SH burden.


Asunto(s)
Angiotensinógeno/genética , Atención/fisiología , Cognición/fisiología , Lenguaje , Desempeño Psicomotor/fisiología , Sustancia Blanca/anatomía & histología , Anciano , Biomarcadores , Imagen de Difusión Tensora , Femenino , Humanos , Masculino , Persona de Mediana Edad , Vías Nerviosas/anatomía & histología , Vías Nerviosas/patología , Pruebas Neuropsicológicas , Polimorfismo de Nucleótido Simple , Factores de Riesgo , Treonina , Sustancia Blanca/patología
18.
J Int Neuropsychol Soc ; 21(10): 880-9, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26581799

RESUMEN

Prior research has suggested benefits of aerobic physical activity (PA) on cognition and brain volumes in HIV uninfected (HIV-) individuals, however, few studies have explored the relationships between PA and brain integrity (cognition and structural brain volumes) in HIV-infected (HIV+) individuals. Seventy HIV+ individuals underwent neuropsychological testing, structural neuroimaging, laboratory tests, and completed a PA questionnaire, recalling participation in walking, running, and jogging activities over the last year. A PA engagement score of weekly metabolic equivalent (MET) hr of activity was calculated using a compendium of PAs. HIV+ individuals were classified as physically active (any energy expended above resting expenditure, n=22) or sedentary (n=48). Comparisons of neuropsychological performance, grouped by executive and motor domains, and brain volumes were completed between groups. Physically active and sedentary HIV+ individuals had similar demographic and laboratory values, but the active group had higher education (14.0 vs. 12.6 years, p=.034). Physically active HIV+ individuals performed better on executive (p=.040, unadjusted; p=.043, adjusted) but not motor function (p=.17). In addition, among the physically active group the amount of physical activity (METs) positively correlated with executive (Pearson's r=0.45, p=0.035) but not motor (r=0.21; p=.35) performance. In adjusted analyses the physically active HIV+ individuals had larger putamen volumes (p=.019). A positive relationship exists between PA and brain integrity in HIV+ individuals. Results from the present study emphasize the importance to conduct longitudinal interventional investigation to determine if PA improves brain integrity in HIV+ individuals.


Asunto(s)
Encéfalo/patología , Infecciones por VIH/patología , Infecciones por VIH/fisiopatología , Actividad Motora/fisiología , Adulto , Encéfalo/virología , Función Ejecutiva , Femenino , Humanos , Imagenología Tridimensional , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Análisis de Regresión , Autoinforme , Trastornos Relacionados con Sustancias/patología , Trastornos Relacionados con Sustancias/fisiopatología
19.
Clin Neuropsychol ; 29(6): 824-35, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26373627

RESUMEN

OBJECTIVE: The Montreal Cognitive Assessment (MoCA) is a brief screening measure commonly used to determine cognitive status among older adults. Despite the popularity of the MoCA, there has been little research into how performance on the MoCA changes over time in healthy older adults. METHODS: The present study examined a sample of older adults (n = 53) recruited for a longitudinal study of healthy aging. Change in total MoCA score at three time points (baseline, 12 months, and 48 months) and scores from the Repeatable Battery for the Assessment of Neuropsychological Status at five time points (RBANS; baseline 12 months, 24 months, 36 months, and 48 months) were assessed using repeated measures analyses. RESULTS: Total MoCA score significantly increased across time, particularly between the first and second administrations. Scores did not significantly differ between the second (12 month) and third (48 month) administrations. When grouped by baseline performance, individuals who scored low at baseline significantly improved performance at 12-month testing, but had little change between 12- and 48-month testing. Conversely, individuals who scored high at baseline did not significantly change between baseline and 12-month testing, but improved between 12- and 48-month testing. RBANS scores did not significantly change over time. CONCLUSIONS: These results suggest that the MoCA may be susceptible to practice effects, particularly between the first and second administrations. These practice effects should be taken into consideration when repeatedly employing the MoCA to screen for cognitive status in healthy older adults.


Asunto(s)
Cognición/fisiología , Pruebas Neuropsicológicas/normas , Anciano , Anciano de 80 o más Años , Envejecimiento , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Proyectos de Investigación
20.
J Neural Transm (Vienna) ; 122(11): 1581-92, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26253899

RESUMEN

Variations of the cholesteryl ester transfer protein polymorphism (CETP I405V/rs5882) have been associated with an increased risk for neurodegeneration, particularly when examined in conjunction with the epsilon 4 isoform of apolipoprotein E (ApoE4). Despite these identified relationships, the impact of I405V on gray matter microstructure remains unknown. The present study examined the impact of the CETP I405V polymorphism on gray matter integrity among 52 healthy adults between ages 51 and 85. Gray matter was measured bilaterally using diffusion tensor imaging (DTI) metrics of fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD). Participants were grouped according to a dominant statistical model (II genotype vs. IV/VV genotypes) and secondary analyses were completed to examine the interactive effects of CETP and ApoE4 on DTI metrics. Compared to individuals with the IV/VV genotypes, II homozygotes demonstrated significantly higher MD in bilateral temporal, parietal, and occipital gray matter. Secondary analyses revealed higher FA and AD in the left temporal lobe of IV/VV genotypes with an ApoE4 allele. Our results provide preliminary evidence that CETP II homozygosity is a predisposing risk factor for gray matter abnormalities in posterior brain regions in healthy older adults, independent of an ApoE4 allele.


Asunto(s)
Transporte Biológico/genética , Encéfalo/metabolismo , Proteínas de Transferencia de Ésteres de Colesterol/genética , Colesterol/metabolismo , Sustancia Gris/metabolismo , Polimorfismo Genético , Anciano , Anciano de 80 o más Años , Anisotropía , Apolipoproteínas E/genética , Encéfalo/patología , Imagen de Difusión por Resonancia Magnética , Imagen de Difusión Tensora , Femenino , Genotipo , Técnicas de Genotipaje , Sustancia Gris/patología , Humanos , Masculino , Persona de Mediana Edad , Modelos Genéticos , Modelos Estadísticos
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