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1.
Dement Geriatr Cogn Disord ; 53(4): 180-189, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38663362

RESUMEN

INTRODUCTION: Neighborhood socioeconomic status (NSES) has been linked with overall health, and this study will evaluate whether NSES is cross-sectionally associated with cognition in non-Hispanic whites (NHWs) and Mexican Americans (MAs) from the Health and Aging Brain: Health Disparities Study (HABS-HD). METHODS: The HABS-HD is a longitudinal study conducted at the University of North Texas Health Science Center. The final sample analyzed (n = 1,312) were 50 years or older, with unimpaired cognition, and underwent an interview, neuropsychological examination, imaging, and blood draw. NSES was measured using the national area deprivation index (ADI) percentile ranking, which considered socioeconomic variables. Executive function and processing speed were assessed by the trail making tests (A and B) and the digit-symbol substitution test, respectively. Linear regression was used to assess the association of ADI and cognitive measures. RESULTS: MAs were younger, more likely to be female, less educated, had higher ADI scores, performed worse on trails B (all p < 0.05), and had lower prevalence of APOE4 + when compared to NHWs (p < 0.0001). A higher percentage of MAs lived in the most deprived neighborhoods than NHWs. For NHWs, ADI did not predict trails B or DSS scores, after adjusting for demographic variables and APOE4. For MAs, ADI predicted trails A, trails B, and DSS after adjusting for demographic covariates and APOE4 status. CONCLUSION: Our study revealed that living in an area of higher deprivation was associated with lower cognitive function in MAs but not in NHWs, which is important to consider in future interventions to slow cognitive decline.


Asunto(s)
Envejecimiento , Función Ejecutiva , Americanos Mexicanos , Pruebas Neuropsicológicas , Clase Social , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Envejecimiento/psicología , Cognición/fisiología , Estudios de Cohortes , Estudios Transversales , Disparidades en el Estado de Salud , Estudios Longitudinales , Americanos Mexicanos/psicología , Características del Vecindario , Velocidad de Procesamiento , Características de la Residencia , Texas/epidemiología , Blanco/psicología
2.
J Alzheimers Dis ; 90(2): 905-915, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36189588

RESUMEN

BACKGROUND: Despite tremendous advancements in the field, our understanding of mild cognitive impairment (MCI) and Alzheimer's disease (AD) among Mexican Americans remains limited. OBJECTIVE: The aim of this study was to characterize MCI and dementia among Mexican Americans and non-Hispanic whites. METHODS: Baseline data were analyzed from n = 1,705 (n = 890 Mexican American; n = 815 non-Hispanic white) participants enrolled in the Health and Aging Brain Study-Health Disparities (HABS-HD). RESULTS: Among Mexican Americans, age (OR = 1.07), depression (OR = 1.09), and MRI-based neurodegeneration (OR = 0.01) were associated with dementia, but none of these factors were associated with MCI. Among non-Hispanic whites, male gender (OR = 0.33), neighborhood deprivation (OR = 1.34), depression (OR = 1.09), and MRI-based neurodegeneration (OR = 0.03) were associated with MCI, while depression (OR = 1.09) and APOEɛ4 genotype (OR = 4.38) were associated with dementia. CONCLUSION: Findings from this study revealed that the demographic, clinical, sociocultural and biomarker characteristics of MCI and dementia are different among Mexican Americans as compared to non-Hispanic whites.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Masculino , Humanos , Americanos Mexicanos/psicología , Vida Independiente , Población Blanca , Factores de Riesgo , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/genética
3.
Front Psychiatry ; 13: 901403, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36081458

RESUMEN

Introduction: Despite tremendous advancements in the research of Alzheimer's disease (AD), Mexican Americans, who reflect 65% of the US Hispanic community, remain severely underrepresented in research. Our data demonstrate that risk factors for, and biomarkers of, AD are different among Mexican Americans as compared with non-Hispanic whites. Here, we examined the impact of depressive symptoms on cognitive and AD-relevant biomarker outcomes among the Mexican Americans. Methods: Data were examined from 1,633 (852 Mexican Americans and 781 non-Hispanic whites) of the Health and Aging Brain Study-Health Disparities (HABS-HD). Depression was assessed using the Geriatric Depression Scale while cognition was measured using detailed neuropsychological testing. Plasma biomarkers of Aß40, Aß42, total tau, and NfL were examined in addition to MRI-based neurodegeneration. PET amyloid data were available in a subset of participants. Results: Depressive symptoms were significantly associated with cognitive testing results among both Mexican Americans and non-Hispanic whites. However, depression was only significantly associated with cognitive outcomes and plasma biomarkers among the Mexican American APOEε4 non-carriers. Discussion: Depressive symptoms are more commonly endorsed by Mexican Americans and these symptoms are more strongly associated with cognitive and AD-biomarker outcomes among this ethnic group. However, depression scores were only related to AD outcomes among APOEε4 non-carriers within the Mexican American group. These findings can aid in the development of a population-informed precision medicine for treating and preventing cognitive loss among the Mexican Americans.

4.
Alzheimers Dement (Amst) ; 14(1): e12263, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35229016

RESUMEN

INTRODUCTION: Among vascular risk factors we hypothesized that an increased prevalence of diabetes in Hispanics would be associated with greater white matter hyperintensity (WMH) volume, which may contribute to cognitive decline. METHODS: A total of 1318 participants (60% female; 49% Hispanic, 51% non-Hispanic White; age 66.2 ± 8.9 years) underwent clinical evaluation and brain magnetic resonance imaging (MRI). WMH volume associations were assessed with age, sex, and ethnicity and then with vascular risk factors in a selective regression model. RESULTS: WMH volume was greater with older age (P < .0001), Hispanic ethnicity (P = .02), and female sex (P = .049). WMH volume was best predicted by age, diastolic blood pressure, hypertension history, hemoglobin A1c (HbA1c), white blood cell count, and hematocrit (P < .01 for all). Elevated HbA1c was associated with greater WMH volume among Hispanics (parameter estimate 0.08 ± 0.02, P < .0001) but not non-Hispanic Whites (parameter estimate 0.02 ± 0.04, P = .5). DISCUSSION: WMH volume was greater in Hispanics, which may be partly explained by increased WMH volume related to elevated HbA1c among Hispanics but not non-Hispanic Whites.

5.
Dement Geriatr Cogn Disord ; 51(1): 26-31, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35226898

RESUMEN

INTRODUCTION: The APOEε4 allele is the single strongest genetic risk for late-onset Alzheimer's disease (AD). Prior work demonstrates that not only the APOEε4 allele varies by race/ethnicity but also the risk for AD and cognitive impairment conveyed by the APOEε4 allele varies by the racial/ethnic group as well as genetic ancestry. Here, we sought to examine the link between the APOEε4 and neuropsychological functioning among Mexican Americans (MAs). METHODS: Data were examined from 1,633 (852 MAs and 781 non-Hispanic Whites [NHWs]) participants of the Health & Aging Brain Study - Health Disparities (HABS-HD) and were enrolled with all requisite data to be included into the current analyses. RESULTS: The frequency of both ε4 and ε2 alleles was significantly lower among MAs as compared to NHWs. Among MAs, APOEε4 allele presence was associated specifically with poorer immediate and delayed memory (Wechsler Memory Scale - Third Edition [WMS-III] Logical Memory and Spanish-English Verbal Learning Test [SEVLT]). Among NHWs, APOEε4 allele presence was associated with poorer immediate and delayed memory as well as worse executive functioning (Trials B) and verbal fluency (Animal naming). DISCUSSION/CONCLUSION: The APOEε4 allele was associated with poorer cognition across multiple domains among NHWs; however, allele presence was specifically associated with poorer memory performance among MAs. When combined with prior work, the current findings demonstrate that the risk factors associated with cognitive dysfunction differ among MAs as compared to NHWs and require additional investigation.


Asunto(s)
Enfermedad de Alzheimer , Apolipoproteína E4 , Envejecimiento/genética , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/psicología , Apolipoproteína E4/genética , Encéfalo , Etnicidad , Humanos , Americanos Mexicanos/genética , Pruebas Neuropsicológicas
6.
J Alzheimers Dis ; 86(3): 1243-1254, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35180110

RESUMEN

BACKGROUND: Hispanics are expected to experience the largest increase in Alzheimer's disease (AD) and AD related dementias over the next several decades. However, few studies have examined biomarkers of AD among Mexican Americans, the largest segment of the U.S. Hispanic population. OBJECTIVE: We sought to examine proteomic profiles of an MRI-based marker of neurodegeneration from the AT(N) framework among a multi-ethnic, community-dwelling cohort. METHODS: Community-dwelling Mexican Americans and non-Hispanic white adults and elders were recruited. All participants underwent comprehensive assessments including an interview, functional exam, clinical labs, informant interview, neuropsychological testing, and 3T MRI of the brain. A neurodegeneration MRI meta-ROI biomarker for the AT(N) framework was calculated. RESULTS: Data was examined from n = 1,291 participants. Proteomic profiles were highly accurate for detecting neurodegeneration (i.e., N+) among both Mexican Americans (AUC = 1.0) and non-Hispanic whites (AUC = 0.98). The proteomic profile of N + was different between ethnic groups. Further analyses revealed that the proteomic profiles of N + varied by diagnostic status (control, MCI, dementia) and ethnicity (Mexican American versus non-Hispanic whites) though diagnostic accuracy was high for all classifications. CONCLUSION: A proteomic profile of neurodegeneration has tremendous value and point towards novel diagnostic and intervention opportunities. The current findings demonstrate that the underlying biological factors associated with neurodegeneration are different between Mexican Americans versus non-Hispanic whites as well as at different levels of disease progression.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Anciano , Enfermedad de Alzheimer/diagnóstico , Biomarcadores , Disfunción Cognitiva/diagnóstico , Humanos , Americanos Mexicanos , Pruebas Neuropsicológicas , Proteómica
7.
Alzheimers Dement (Amst) ; 14(1): e12267, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35155729

RESUMEN

INTRODUCTION: We sought to examine a magnetic resonance imaging (MRI)-based marker of neurodegeneration from the AT(N) (amyloid/tau/neurodegeneration) framework among a multi-ethnic, community-dwelling cohort. METHODS: Community-dwelling Mexican Americans and non-Hispanic White adults and elders were recruited. All participants underwent comprehensive assessments including an interview, functional exam, clinical labs, informant interview, neuropsychological testing and 3T MRI of the brain. A neurodegeneration MRI meta-region of interest (ROI) biomarker for the AT(N) framework was calculated. RESULTS: Data were examined from n = 1305 participants. Mexican Americans experienced N at significantly younger ages. The N biomarker was significantly associated with cognitive outcomes. N was significantly impacted by cardiovascular factors (e.g., total cholesterol, low-density lipoprotein) among non-Hispanic Whites whereas diabetes (glucose, HbA1c, duration of diabetes) and sociocultural (household income, acculturation) factors were strongly associated with N among Mexican Americans. DISCUSSION: The prevalence, progression, timing, and sequence of the AT(N) biomarkers must be examined across diverse populations.

8.
Alzheimers Dement ; 18(1): 77-87, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34057802

RESUMEN

INTRODUCTION: Representation of Mexican Americans in Alzheimer's disease (AD) clinical research has been extremely poor. METHODS: Data were examined from the ongoing community-based, multi-ethnic Health & Aging Brain among Latino Elders (HABLE) study. Participants underwent functional exams, clinical labs, neuropsychological testing, and 3T magnetic resonance imaging of the brain. Fasting proteomic markers were examined for predicting mild cognitive impairment (MCI) and AD using support vector machine models. RESULTS: Data were examined from n = 1649 participants (Mexican American n = 866; non-Hispanic White n = 783). Proteomic profiles were highly accurate in detecting MCI (area under the curve [AUC] = 0.91) and dementia (AUC = 0.95). The proteomic profiles varied significantly between ethnic groups and disease state. Negative predictive value was excellent for ruling out MCI and dementia across ethnic groups. DISCUSSION: A blood-based screening tool can serve as a method for increasing access to state-of-the-art AD clinical research by bridging between community-based and clinic-based settings.


Asunto(s)
Enfermedad de Alzheimer/sangre , Enfermedad de Alzheimer/diagnóstico , Disfunción Cognitiva/diagnóstico , Vida Independiente , Tamizaje Masivo , Americanos Mexicanos/estadística & datos numéricos , Población Blanca/estadística & datos numéricos , Anciano , Enfermedad de Alzheimer/etnología , Biomarcadores/sangre , Disfunción Cognitiva/sangre , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas , Selección de Paciente , Proteómica
9.
Dement Geriatr Cogn Disord ; 50(3): 266-273, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34569492

RESUMEN

INTRODUCTION: Alzheimer's disease (AD) is the most frequently occurring neurodegenerative disease; however, little work has been conducted examining biomarkers of AD among Mexican Americans. Here, we examined diffusion tensor MRI marker profiles for detecting mild cognitive impairment (MCI) and dementia in a multi-ethnic cohort. METHODS: 3T MRI measures of fractional anisotropy (FA) were examined among 1,636 participants of the ongoing community-based Health & Aging Brain among Latino Elders (HABLE) community-based study (Mexican American n = 851; non-Hispanic white n = 785). RESULTS: The FA profile was highly accurate in detecting both MCI (area under the receiver operating characteristic curve [AUC] = 0.99) and dementia (AUC = 0.98). However, the FA profile varied significantly not only between diagnostic groups but also between Mexican Americans and non-Hispanic whites. CONCLUSION: Findings suggest that diffusion tensor imaging markers may have a role in the neurodiagnostic process for detecting MCI and dementia among diverse populations.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Enfermedades Neurodegenerativas , Anciano , Envejecimiento , Enfermedad de Alzheimer/diagnóstico por imagen , Anisotropía , Encéfalo/diagnóstico por imagen , Disfunción Cognitiva/diagnóstico por imagen , Imagen de Difusión Tensora , Humanos , Americanos Mexicanos
10.
Curr Alzheimer Res ; 17(13): 1214-1220, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33605860

RESUMEN

INTRODUCTION: This study characterized the relationship between plasma NfL and cognition in a community-based sample of older Mexican Americans. METHODS: 544 participants completed a battery of neuropsychological tests and were diagnosed using clinical criteria. NfL was assayed using Simoa. NfL levels across groups and tests were analyzed. RESULTS: Difference in NfL was found between normal and impaired groups and was related to global cognition, processing speed, executive functions and a list of learning tasks with a significant negative effect for all diagnostic groups. NfL had a negative impact on processing speed, attention, executive functions and delayed and recognition memory for both normal and MCI groups. CONCLUSION: The research supports plasma NfL as a marker of cognitive impairment related to neurodegenerative processes in Mexican Americans and may be a marker of early changes in cognition in those with normal cognition and at risk for developing MCI.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/fisiopatología , Biomarcadores/sangre , Cognición/fisiología , Disfunción Cognitiva/metabolismo , Disfunción Cognitiva/fisiopatología , Americanos Mexicanos/estadística & datos numéricos , Proteínas de Neurofilamentos/metabolismo , Factores de Edad , Anciano , Enfermedad de Alzheimer/sangre , Disfunción Cognitiva/sangre , Función Ejecutiva , Femenino , Voluntarios Sanos , Humanos , Vida Independiente , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas/estadística & datos numéricos
11.
Curr Neurobiol ; 10(1): 22-25, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31061568

RESUMEN

BACKGROUND: The presence of Subjective Cognitive Decline (SCD) in the absence of objective change and the inflammatory biomarker Alpha 2 Macroglobulin (A2M) have both been implicated in preclinical Alzheimer's disease. Mexican Americans are population with high rates of cardiovascular and inflammatory disorders. OBJECTIVES: The current study investigated the levels of A2M in cognitively normal Mexican Americans with and without complaints of cognitive decline. METHOD: 293 (243 females, 50 males) community-based cognitively normal older Mexican Americans from the ongoing Health and Aging Brain among Latino Elders (HABLE) study were grouped based on subjective cognitive decline and blood samples were assayed by electrochemiluminescence to determine levels of A2M. RESULTS: Participants with SCD had significantly higher levels of A2M than those without SCD. Females with SCD had a significantly higher level of A2M. CONCLUSIONS: Results suggest that higher levels of A2M, a marker of neuronal injury, may be involved in subtle changes in cognitive functioning recognizable to persons reporting SCD but too subtle to be objectively measured. Longitudinal research is needed to assess the impact of SDC and A2M in progression to MCI and dementia in Mexican Americans.

12.
Curr Aging Sci ; 11(4): 236-241, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30767759

RESUMEN

BACKGROUND: Falls are common among elderly adults, and are predictors of hospitalization, institutionalization and mortality. OBJECTIVE: The objective of the present study was to examine the relationship between blood-based markers of inflammation and fall events in a sample of elderly Hispanic adults. METHOD: Data were collected from 190 participants enrolled in the Panama Aging Research Initiative study who completed baseline clinical and cognitive assessments. A non-fasting blood sample was obtained. Self-reported falls were classified as no falls, single falls or recurrent (two or more) falls reported in the 12 months prior to baseline evaluations. Serum levels of C Reactive Protein (CRP), T-lymphocyte secreting protein (I-309), interleukin 10 (IL-10), interleukin 6 (IL-6) and interleukin 7 (IL-7) were measured. Global cognition was assessed with the Mini Mental State Examination and depressive symptoms were assessed with the Geriatric Depression Scale (GDS-30). Multinomial logistic regression was used to assess the link between inflammation and fall events. RESULTS: Depressive symptoms, limitations in Instrumental Activities of Daily Living (IADL), IL-7 and I-309 were significantly related to fall events. Elevated levels of IL-7 increased the likelihood of single and recurrent falls, while increased levels of I-309 were associated only with recurrent falls. Greater IADL limitations and depressive symptoms were associated with an increased likelihood of recurrent falls. CONCLUSION: There is a lack of research investigating the relationship between inflammatory biomarkers and fall events. These results provide evidence of risk factors for falls in Hispanic older adults, and could serve to guide public health professionals to establish clinical guidelines to reduce fall risks.


Asunto(s)
Accidentes por Caídas , Envejecimiento/sangre , Envejecimiento/psicología , Depresión/sangre , Mediadores de Inflamación/sangre , Accidentes por Caídas/prevención & control , Accidentes por Caídas/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Proteína C-Reactiva/metabolismo , Quimiocina CCL1/sangre , Depresión/complicaciones , Femenino , Hispánicos o Latinos , Humanos , Incidencia , Interleucina-10/sangre , Interleucina-6/sangre , Interleucina-7/sangre , Masculino , Panamá/epidemiología , Factores de Riesgo
13.
Dement Geriatr Cogn Dis Extra ; 8(1): 151-157, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29805381

RESUMEN

BACKGROUND: Recent evidence suggests that increasing dietary intake of minerals reduces the risk of dementia. This study aimed to examine the relationship between potassium and diagnosis of mild cognitive impairment (MCI) in a sample of older Mexican-Americans from rural and urban populations. METHODS: The sample was formed of a total of 139 participants with MCI and 371 normal controls from two independent cohorts: a rural cohort (Facing Rural Obstacles to Healthcare Now through Intervention, Education and Research [Project FRONTIER]) and an urban cohort (the Health and Aging Brain among Latino Elders [HABLE] study). Serum electrolytes examined were sodium and potassium. Age and education were entered in the model as covariates. RESULTS: Across both cohorts, the Project FRONTIER (OR = 3.1; p = 0.01) and the HABLE Project (OR = 2.0; p = 0.04), the results indicated that serum potassium levels significantly increased the risk of diagnosis of MCI. CONCLUSION: Our finding suggested a link between serum potassium levels and a diagnosis of MCI in Mexican-Americans. The results of this study support a previous research which has suggested that the risk factors for MCI may vary by ethnicity.

14.
J Alzheimers Dis ; 61(4): 1485-1492, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29376872

RESUMEN

BACKGROUND: Subjective cognitive complaints in cognitively normal adults have been linked to later cognitive decline and dementia. Research on the characteristics of this group has been conducted on a variety of clinical and community-based populations. The current study focuses on the rapidly expanding population of Mexican-American elders. OBJECTIVE: The objective of the study is the determination of characteristics of cognitively normal Mexican-Americans with cognitive complaints. METHODS: Data on 319 cognitively normal participants in a large-scale community-based study of elderly Mexican-Americans (HABLE) were analyzed comparing those with cognitive complaints with those without on clinical characteristics, affective status, neuropsychological functioning, and proteomic markers. RESULTS: Those expressing concern about cognitive decline scored lower on the MMSE, were more likely to have significantly more affective symptoms, higher levels of diabetic markers, poorer performance on attention and executive functioning, and a different pattern of inflammatory markers. CONCLUSION: Although longitudinal research is needed to determine the impact of these differences on later cognition, possible targets for early intervention with Mexican-Americans were identified.


Asunto(s)
Biomarcadores/sangre , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/etnología , Americanos Mexicanos , Anciano , Cognición , Función Ejecutiva , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Factores de Riesgo , Texas/epidemiología
15.
Dev Neuropsychol ; 43(1): 27-35, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29185823

RESUMEN

The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) is an assessment of neuropsychological functioning commonly used in clinical and research settings. To our knowledge, normative data for the RBANS is not available for Hispanic, Mexican Americans, which the current study sought to establish. Data from 136 Hispanic, Mexican Americans from Project FRONTIER were analyzed. Approximately half of the sample was administered testing in Spanish. Normative tables were created for English and Spanish speaking Mexican Americans. Generated RBANS normative references are provided for unadjusted raw scores as well as output adjusted by education level.


Asunto(s)
Pruebas Neuropsicológicas , Adulto , Anciano , Femenino , Humanos , Lenguaje , Masculino , Americanos Mexicanos , Persona de Mediana Edad , Texas
16.
Am J Bot ; 104(11): 1729-1744, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-29158342

RESUMEN

PREMISE OF THE STUDY: Following establishment after long-distance dispersal, species may experience stasis, accumulate changes leading to new species identity, diversify into multiple species, interact with related species to form novel species, and even become extirpated. We examined each species of temperate Polemoniaceae in South America via the literature and new analyses to better understand the fates of species in this family after their dispersal from North America. METHODS: We reviewed literature for the 15 species of Polemoniaceae in South America amphitropically disjunct from their relatives in North America. We conducted DNA sequence analyses to infer relationships, timing of dispersal, and processes involved since dispersal in Microsteris gracilis, three Gilia, two Giliastrum, and three Collomia. Analyses included construction of haplotype networks and phylogenetic trees using maximum likelihood and Bayesian inference. KEY RESULTS: For all species examined in detail, origins in South America are compatible with dispersal via epizoochory from ca. 0.092-19.46 million years ago. Most species in South America are unique relative to their North American congeners, yet few have radiated into two or more species. Relative stasis, divergence, and hybridization with, and without, allopolyploid formation have occurred postdispersal in Polemoniaceae, as well as extirpation following at least brief establishment. CONCLUSIONS: Polemoniaceae that have established in South America share many features likely inherited from their North American progenitors, but some traits may have arisen in situ in specific taxa, such as cleistogamy, self-incompatibility, and the annual habit, evidencing the rich nature of diversification processes.


Asunto(s)
Magnoliopsida/fisiología , Dispersión de las Plantas , Teorema de Bayes , Hibridación Genética , Magnoliopsida/genética , América del Norte , Fenotipo , Filogenia , Semillas/genética , Semillas/fisiología , Análisis de Secuencia de ADN , América del Sur
17.
PLoS One ; 12(6): e0178827, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28582433

RESUMEN

Effects of Pleistocene climatic oscillations on plant phylogeographic patterns are relatively well studied in forest, savanna and grassland biomes, but such impacts remain less explored on desert regions of the world, especially in South America. Here, we performed a phylogeographical study of Monttea aphylla, an endemic species of the Monte Desert, to understand the evolutionary history of vegetation communities inhabiting the South American Arid Diagonal. We obtained sequences of three chloroplast (trnS-trnfM, trnH-psbA and trnQ-rps16) and one nuclear (ITS) intergenic spacers from 272 individuals of 34 localities throughout the range of the species. Population genetic and Bayesian coalescent analyses were performed to infer genealogical relationships among haplotypes, population genetic structure, and demographic history of the study species. Timing of demographic events was inferred using Bayesian Skyline Plot and the spatio-temporal patterns of lineage diversification was reconstructed using Bayesian relaxed diffusion models. Palaeo-distribution models (PDM) were performed through three different timescales to validate phylogeographical patterns. Twenty-five and 22 haplotypes were identified in the cpDNA and nDNA data, respectively. that clustered into two main genealogical lineages following a latitudinal pattern, the northern and the southern Monte (south of 35° S). The northern Monte showed two lineages of high genetic structure, and more relative stable demography than the southern Monte that retrieved three groups with little phylogenetic structure and a strong signal of demographic expansion that would have started during the Last Interglacial period (ca. 120 Ka). The PDM and diffusion models analyses agreed in the southeast direction of the range expansion. Differential effect of climatic oscillations across the Monte phytogeographic province was observed in Monttea aphylla lineages. In northern Monte, greater genetic structure and more relative stable demography resulted from a more stable climate than in the southern Monte. Pleistocene glaciations drastically decreased the species area in the southern Monte, which expanded in a southeastern direction to the new available areas during the interglacial periods.


Asunto(s)
ADN de Cloroplastos/genética , ADN Mitocondrial/genética , Modelos Estadísticos , Filogenia , Dispersión de las Plantas/fisiología , Plantaginaceae/genética , Argentina , Teorema de Bayes , Clima Desértico , Variación Genética , Haplotipos , Historia del Siglo XXI , Historia Antigua , Filogeografía , Plantaginaceae/clasificación , Análisis Espacio-Temporal
18.
Int Psychogeriatr ; 29(10): 1693-1699, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28629481

RESUMEN

BACKGROUND: This study explored the combined impact of depression and inflammation on memory functioning among Mexican-American adults and elders. METHODS: Data were analyzed from 381 participants of the Health and Aging Brain study among Latino Elders (HABLE). Fasting serum samples were collected and assayed in duplicate using electrochemiluminesce on the SECTOR Imager 2400A from Meso Scale Discovery. Positive DepE (depression endophenotype) was codified as any score >1 on a five-point scale based on the GDS-30. Inflammation was determined by TNFα levels and categorized by tertiles (1st, 2nd, 3rd). WMS-III LMI and LMII as well as CERAD were utilized as measures of memory. ANOVAs examined group differences between positive DepE and inflammation tertiles with neuropsychological scale scores as outcome variables. Logistic regressions were used to examine level of inflammation and DepE positive status on the risk for MCI. RESULTS: Positive DepE as well as higher inflammation were both independently found to be associated with lower memory scores. Among DepE positive, those who were high in inflammation (3rd tertile) were found to perform significantly worse on WMS-III LM I (F = 4.75, p = 0.003), WMS-III LM II (F = 8.18, p < 0.001), and CERAD List Learning (F = 17.37, p < 0.001) when compared to those low on inflammation (1st tertile). The combination of DepE positive and highest tertile of inflammation was associated with increased risk for MCI diagnosis (OR = 6.06; 95% CI = 3.9-11.2, p < 0.001). CONCLUSION: Presence of elevated inflammation and positive DepE scores increased risk for worse memory among Mexican-American older adults. Additionally, the combination of DepE and high inflammation was associated with increased risk for MCI diagnosis. This work suggests that depression and inflammation are independently associated with worse memory among Mexican-American adults and elders; however, the combination of both increases risk for poorer memory beyond either alone.


Asunto(s)
Disfunción Cognitiva/etnología , Depresión/etnología , Inflamación/etnología , Trastornos de la Memoria/etnología , Americanos Mexicanos , Anciano , Disfunción Cognitiva/complicaciones , Estudios de Cohortes , Depresión/complicaciones , Femenino , Humanos , Inflamación/complicaciones , Modelos Logísticos , Masculino , Trastornos de la Memoria/complicaciones , Persona de Mediana Edad , Pruebas Neuropsicológicas , Factores de Riesgo , Estados Unidos/epidemiología
19.
J Alzheimers Dis ; 54(1): 201-6, 2016 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-27472872

RESUMEN

BACKGROUND: Late life depression is a prodromal feature and a risk factor for Alzheimer's disease (AD) and mild cognitive impairment (MCI). We identified five items in the Geriatric Depression scale (DepE) that are important as a risk for MCI and AD: memory problems, feeling blue, crying, feeling worthless, and trouble concentrating. OBJECTIVE: Our goal was to examine the relationship between DepE and cognition in a cohort of Mexican Americans. METHODS: Data from 317 Mexican Americans from the HABLE study were analyzed. DepE scores were dichotomized into two groups: endorsement of 1 item or less, and endorsement of 2 or more items. Cognition was assessed via neuropsychological tests, and diagnosis was based on consensus review. We utilized linear regression to examine the association between DepE and cognitive performance, and logistic regression to examine the utility of DepE in predicting MCI. To examine the impact of DepE on memory over 12 months, we performed ANOVA analysis. RESULTS: Elevated DepE scores were associated with poorer performance on various measures of memory and cognition, but not executive or visual spatial skills. Over 12 months, we found a decline in immediate memory among women but not men. Those with high scores were 4 times more likely to have MCI. ANOVA of total scores revealed differences between groups on immediate memory (p < 0.05) in women, with no significant differences on delay recall in either gender. CONCLUSION: DepE can be utilized in Mexican Americans to identify those at risk of memory related cognitive decline.


Asunto(s)
Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/etnología , Depresión/diagnóstico , Depresión/etnología , Americanos Mexicanos/psicología , Anciano , Anciano de 80 o más Años , Cognición , Envejecimiento Cognitivo , Endofenotipos , Función Ejecutiva , Femenino , Humanos , Estudios Longitudinales , Masculino , Memoria , Persona de Mediana Edad , Pruebas Neuropsicológicas , Escalas de Valoración Psiquiátrica , Factores Sexuales , Percepción Espacial , Percepción Visual
20.
J Am Geriatr Soc ; 63(10): 2023-8, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26456700

RESUMEN

OBJECTIVES: To analyze the association between chronic kidney disease (CKD) and mild cognitive impairment (MCI) in Mexican Americans and to determine whether there is a blood-based proteomic profile linking CKD to MCI. DESIGN: Retrospective analysis of cohort study. SETTING: Health and Aging Brain among Latino Elders study. PARTICIPANTS: Mexican Americans (N = 437, 105 men, 332 women). MEASUREMENTS: Data were analyzed to examine the link between estimated glomerular filtration rate (eGFR) and detailed neuropsychological functioning. Serum proteomic markers were also examined. RESULTS: Lower eGFR levels were associated with significantly poorer neuropsychological functioning across multiple domains. After adjusting for age, sex, education, and diabetes mellitus, participants with an eGFR less than 45 mL/min per 1.73 m(2) performed significantly worse than those with an eGFR from 45 to 59 mL/min per 1.73 m(2) or 60 mL/min per 1.73 m(2) and higher in processing speed (F = 14.1, P < .001), executive functioning (F = 4.5, P = .01), visuospatial skills (F = 4.8, P = .009), and global cognitive functioning (F = 6.2, P = .002). Participants with an eGFR less than 45 mL/min per 1.73 m(2) also performed significantly worse than those with an eGFR of 60 mL/min per 1.73 m(2) or greater on delayed memory (F = 3.8, P = .02). There was a trend toward lower eGFR levels being associated with greater risk of MCI (odds ratio (OR) = 2.4, 95% confidence interval (CI) = 0.91-6.1, P = .07), which was stronger for men (OR = 9.6, 95% CI = 1.3-74.3, P = .03). A serum proteomic profile consisting of Factor VII, interleukin-10, C-reactive protein, and fatty acid binding protein was 93% accurate in detecting CKD-related MCI. CONCLUSION: Lower eGFR was associated with significantly poorer neuropsychological functioning in Mexican Americans. A blood-based profile was generated that was highly accurate in detecting CKD-related MCI. A blood profile capable of predicting CKD-related cognitive impairment would be of benefit for the design of clinical interventions.


Asunto(s)
Disfunción Cognitiva/diagnóstico , Tasa de Filtración Glomerular , Americanos Mexicanos , Insuficiencia Renal Crónica/epidemiología , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Proteína C-Reactiva/análisis , Disfunción Cognitiva/epidemiología , Estudios de Cohortes , Factor VII/análisis , Proteínas de Unión a Ácidos Grasos/sangre , Femenino , Humanos , Interleucina-10/sangre , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Estudios Retrospectivos , Factores Sexuales , Estados Unidos/epidemiología
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