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1.
J Nat Prod ; 85(8): 1893-1903, 2022 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-35881529

RESUMEN

The methyl-migrated bicyclic skeleton of the halimane diterpenes has been found in a wide range of organisms, including flowering plants, liverworts, marine animals, and bacteria. The discovery of halima-1(10),14-dien-13-ol (3) from the Aotearoa New Zealand endemic alpine daisy Celmisia viscosa is now reported. The full configuration was assigned for the first time by X-ray crystallography, enantiomeric to that of a liverwort isolate. The absolute configuration at C-5 of the halimane is opposite to that at C-5 of the labdane epimanool (1) found in some C. viscosa specimens. Two new 2,6-dideoxyhexopyran-3-uloside halimane derivatives (4 and 5) were also found, and the absolute configuration of 5 was determined by 1H NMR analysis of the Mosher esters. Line broadening in the 13C NMR spectra of these halim-1(10)-enes was due to conformational exchange in the decalin ring A, as shown by molecular modeling and DFT calculations. 1H NMR and GC analyses of leaf extracts of individual plants from across the full geographic range of C. viscosa revealed intraspecific variation of diterpenes: 37 samples had halimadienol as the main diterpene in large amounts and 2 specimens had predominantly epimanool, again in large amounts. Three other viscid (sticky leaved) Celmisia species also contained diterpenes, but none was detectable in four nonviscid Celmisia species.


Asunto(s)
Diterpenos , Animales , Cristalografía por Rayos X , Diterpenos/química , Conformación Molecular , Estructura Molecular
2.
BMC Public Health ; 19(1): 523, 2019 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-31064373

RESUMEN

BACKGROUND: This paper analyses the 2008 economic collapse in Spain with its long-lasting effects. Precisely, the ones associated with lifestyles. Thus, the aim of this paper is to examine to what extent economic downturns affect individual's drinking behavior when focusing on unemployed people. METHODS: We use discrete-choice models and matching techniques. Data from the National Health Survey for 2006 and 2011-2012 provides a clear picture before and after the 2008 breakdown in Spain. RESULTS: We find that drinking over the business cycle is a function of individual socio-demographic status. Besides, our empirical findings are consistent with the idea that following the crisis differences between unemployed and non-unemployed fell to at least in accordance with a lower overall consumption of alcoholic beverages. CONCLUSIONS: Public policy design for drinkers would require both prevention and recovery from alcohol use strategies to be met towards health and labour pillars.


Asunto(s)
Consumo de Bebidas Alcohólicas/epidemiología , Recesión Económica , Desempleo/psicología , Adolescente , Adulto , Consumo de Bebidas Alcohólicas/psicología , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad , Política Pública , Factores Socioeconómicos , España/epidemiología , Desempleo/estadística & datos numéricos
3.
Sensors (Basel) ; 18(2)2018 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-29470432

RESUMEN

This work introduces a new vision-based approach for estimating chlorophyll contents in a plant leaf using reflectance and transmittance as base parameters. Images of the top and underside of the leaf are captured. To estimate the base parameters (reflectance/transmittance), a novel optical arrangement is proposed. The chlorophyll content is then estimated by using linear regression where the inputs are the reflectance and transmittance of the leaf. Performance of the proposed method for chlorophyll content estimation was compared with a spectrophotometer and a Soil Plant Analysis Development (SPAD) meter. Chlorophyll content estimation was realized for Lactuca sativa L., Azadirachta indica, Canavalia ensiforme, and Lycopersicon esculentum. Experimental results showed that-in terms of accuracy and processing speed-the proposed algorithm outperformed many of the previous vision-based approach methods that have used SPAD as a reference device. On the other hand, the accuracy reached is 91% for crops such as Azadirachta indica, where the chlorophyll value was obtained using the spectrophotometer. Additionally, it was possible to achieve an estimation of the chlorophyll content in the leaf every 200 ms with a low-cost camera and a simple optical arrangement. This non-destructive method increased accuracy in the chlorophyll content estimation by using an optical arrangement that yielded both the reflectance and transmittance information, while the required hardware is cheap.


Asunto(s)
Clorofila/análisis , Algoritmos , Solanum lycopersicum , Hojas de la Planta , Espectrofotometría
4.
Artículo en Inglés | MEDLINE | ID: mdl-39477818

RESUMEN

STUDY DESIGN: A systematic review and meta-analysis. OBJECTIVE: To conduct a meta-analysis of studies that compared surgery with or without radiotherapy to radiotherapy alone for patients with malignant spinal cord compression, and a subgroup analysis of patients stratified by hematologic and solid malignancies. SUMMARY OF BACKGROUND DATA: Two previous meta-analyses showed that surgery with or without radiotherapy was better than radiotherapy alone in patients with malignant spinal cord compression. Nevertheless, there was no stratification by tumor type, leading to uncertainty regarding best approach for patients with hematologic malignancies. METHODS: We searched PubMed, Scopus, and Web of Science, for studies comparing surgery with or without radiotherapy to radiotherapy alone in patients with malignant spinal cord compression. The primary outcomes were improvement in ambulatory status and survival at 12 months. For neurological outcomes, we included studies involving both locally advanced primary malignancies of the spine and metastatic tumors. We restricted our analysis to studies on metastases for survival outcomes. RESULTS: We included 2536 patients from 18 studies. Surgery was performed in 890 (35%) patients. The pooled analysis of all studies revealed that improvement in ambulatory status (OR 2.65; 95% CI 1.60-4.39) and survival at 12 months (OR 1.66; 95% CI 1.10-2.52) were significantly higher in patients who underwent surgery with or without radiotherapy. Improvement in ambulatory status (OR 1.92; 95% CI 1.19-3.09) and survival at 12 months (OR 4.24; 95% CI 2.35-7.66) were significantly higher in patients with hematologic malignancies in the surgical arm. The primary outcomes were not significantly different between patients with solid malignancies. CONCLUSION: Surgical intervention demonstrates superior neurological outcomes and increased survival compared with radiotherapy alone. Subgroup analysis revealed that patients with hematologic malignancies on surgery group experienced superior primary outcomes; however, high risk of bias of the included studies preclude definitive changes in standard care based on this data. These findings underscore the need for further research regarding the efficacy of surgical versus radiotherapeutic approaches for specific tumor types. LEVEL OF EVIDENCE: 2.

5.
Animals (Basel) ; 14(13)2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38997962

RESUMEN

Aquaculture requires precise non-invasive methods for biomass estimation. This research validates a novel computer vision methodology that uses a signature function-based feature extraction algorithm combining statistical morphological analysis of the size and shape of fish and machine learning to improve the accuracy of biomass estimation in fishponds and is specifically applied to tilapia (Oreochromis niloticus). These features that are automatically extracted from images are put to the test against previously manually extracted features by comparing the results when applied to three common machine learning methods under two different lighting conditions. The dataset for this analysis encompasses 129 tilapia samples. The results give promising outcomes since the multilayer perceptron model shows robust performance, consistently demonstrating superior accuracy across different features and lighting conditions. The interpretable nature of the model, rooted in the statistical features of the signature function, could provide insights into the morphological and allometric changes at different developmental stages. A comparative analysis against existing literature underscores the competitiveness of the proposed methodology, pointing to advancements in precision, interpretability, and species versatility. This research contributes significantly to the field, accelerating the quest for non-invasive fish biometrics that can be generalized across various aquaculture species in different stages of development. In combination with detection, tracking, and posture recognition, deep learning methodologies such as the one provided in the latest studies could generate a powerful method for real-time fish morphology development, biomass estimation, and welfare monitoring, which are crucial for the effective management of fish farms.

6.
J Virol ; 86(10): 5931-6, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22398280

RESUMEN

TNPO3 is a nuclear importer required for HIV-1 infection. Here, we show that depletion of TNPO3 leads to an HIV-1 block after nuclear import but prior to integration. To investigate the mechanistic requirement of TNPO3 in HIV-1 infection, we tested the binding of TNPO3 to the HIV-1 core and found that TNPO3 binds to the HIV-1 core. Overall, this work suggests that TNPO3 interacts with the incoming HIV-1 core in the cytoplasm to assist a process that is important for HIV-1 infection after nuclear import.


Asunto(s)
Núcleo Celular/metabolismo , Infecciones por VIH/metabolismo , Infecciones por VIH/virología , VIH-1/fisiología , Integración Viral , Replicación Viral , beta Carioferinas/metabolismo , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/metabolismo , Transporte Activo de Núcleo Celular , Núcleo Celular/genética , Núcleo Celular/virología , Citoplasma/genética , Citoplasma/metabolismo , Citoplasma/virología , Infecciones por VIH/genética , VIH-1/genética , Humanos , Unión Proteica , beta Carioferinas/genética , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/genética
7.
Psychol Rep ; 126(1): 265-287, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34772304

RESUMEN

Neuroticism has been linked to an increased likelihood of cognitive failures, including episodes of inattentiveness, forgetfulness, or accidents causing difficulties in successfully executing everyday tasks and impacting health and quality of life. Cognitive failures associated with trait neuroticism can prompt some negative psychological outcomes and risky behaviors. Accumulating evidence shows that augmenting mindfulness can benefit cognitive health and general well-being. However, little is known regarding potential cognitive-behavioral pathways through which individual differences in trait neuroticism could influence the propensity to cognitive failures. Using a sample of 1003 undergraduate college students (females: n = 779) consisting of self-reported questionnaire data, we conducted correlational and mediational analyses to investigate the interrelationship between neuroticism, mindfulness, and cognitive failures. Higher neuroticism scores (females: r = -0.388, males: r = -0.390) and higher cognitive failures scores (females: r = -0.339, males: r = -0.407, p < .001) were significantly correlated with lower self-reported mindfulness scores. Mindfulness significantly mediated the relationship between neuroticism and cognitive failures (ß = 0.50, 95%, CI: 0.37, 0.65). These findings indicate that higher mindfulness may help ameliorate negative effects of neuroticism on everyday cognitive failures. Future research will determine how college students may benefit from positive impact of mindfulness to improve their psychological and physical health.


Asunto(s)
Atención Plena , Masculino , Femenino , Humanos , Neuroticismo , Autoinforme , Calidad de Vida , Estudiantes/psicología , Cognición
8.
Addict Behav ; 135: 107458, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35998541

RESUMEN

BACKGROUND: Adolescent electronic cigarette (e-cigarette) use remains high. Elucidating contributing factors may enhance prevention strategies. Neurobiologically, amygdala-insula resting-state functional connectivity (rsFC) has been linked with aspects of sleep, affect, and substance use (SU). As such, we hypothesized that amygdala's rsFC with the insula would be associated with e-cigarette use via sleep problems and/or depression levels. METHODS: An adolescent sample (N = 146) completed a rs-fMRI scan at time 1 and self-reports at time 2 (∼15 months later). Given consistent associations between mental health outcomes and the rsFC of the laterobasal amygdala (lbAMY) with the anterior insula, we utilized a seed region (lbAMY) to region of interest (ROI) analysis approach to characterize brain-behavior relationships. Two serial mediation models tested the interrelations between amygdala's rsFC with distinct anterior insula subregions (i.e., ventral insula [vI], dorsal insula [dI]), sleep problems, depression levels, and days of e-cigarette use. RESULTS: An indirect effect was observed when considering the lbAMY's rsFC with the vI. Greater rsFC predicted more sleep problems, more sleep problems were linked with greater depressive symptoms, and greater depressive symptoms were associated with more e-cigarette use (indirect effect = 0.08, CI [0.01,0.21]). Indicative of a neurobiological dissociation, a similar indirect effect linking these variables was not observed when considering the lbAMY's rsFC with the dI (indirect effect = 0.03, CI [-0.001,0.10]). CONCLUSIONS: These outcomes highlight functional interactions between the amygdala and insula as a neurobiological contributor to sleep problems, depressive symptoms, and ultimately SU thereby suggesting potential intervention points to reduce teen e-cigarette use.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Trastornos del Sueño-Vigilia , Vapeo , Adolescente , Amígdala del Cerebelo/diagnóstico por imagen , Corteza Cerebral/diagnóstico por imagen , Depresión , Humanos , Imagen por Resonancia Magnética , Trastornos del Sueño-Vigilia/diagnóstico por imagen
9.
Transbound Emerg Dis ; 69(6): e3462-e3468, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36327129

RESUMEN

Seneca Valley virus (SVV) is a non-enveloped RNA virus and the only member of the Senecavirus A (SVA) species, in the Senecavirus genus, Picornaviridae family. SVV infection causes vesicular lesions in the oral cavity, snout and hooves of pigs. This infection is clinically indistinguishable from trade-restrictions-related diseases such as foot-and-mouth disease. Other clinical manifestations include diarrhoea, anorexia, lethargy, neurological signs and mortality in piglets during their first week of age. Before this study, Chile was considered free of vesicular diseases of swine, including SVV. In April 2022, a suspected case of vesicular disease in a swine farm was reported in Chile. The SVV was confirmed and other vesicular diseases were ruled out. An epidemiological investigation and phylogenetic analyses were performed to identify the origin and extent of the outbreak. Three hundred ninety-five samples from 44 swine farms were collected, including faeces (208), oral fluid (28), processing fluid (14), fresh semen (61), environmental samples (80) and tissue from lesions (4) for real-time RT-PCR detection. Until June 2022, the SVV has been detected in 16 out of 44 farms, all epidemiologically related to the index farm. The closest phylogenetic relationship of the Chilean SVV strain is with viruses collected from swine in California in 2017. The direct cause of the SVV introduction has not yet been identified; however, the phylogenetic analyses suggest the USA as the most likely source. Since the virus remains active in the environment, transmission by fomites such as contaminated feed cannot be discarded. Further studies are needed to determine the risk of the introduction of novel SVV and other transboundary swine pathogens to Chile.


Asunto(s)
Infecciones por Picornaviridae , Picornaviridae , Enfermedades de los Porcinos , Animales , Porcinos , Infecciones por Picornaviridae/epidemiología , Infecciones por Picornaviridae/veterinaria , Infecciones por Picornaviridae/diagnóstico , Chile/epidemiología , Filogenia , Picornaviridae/genética , ARN Viral
10.
Physiother Theory Pract ; 38(13): 2368-2377, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34074220

RESUMEN

BACKGROUND: The effectiveness of Manual Therapy (MT) in thumb carpometacarpal osteoarthritis (OA) is unclear. OBJECTIVE: This study aimed to determine the effectiveness of MT for functional outcomes in patients with thumb carpometacarpal OA. DESIGN: Systematic review and meta-analysis of randomized clinical trials. METHODS: An electronic search was performed in the Medline, Central, Embase, PEDro, Lilacs, Cinahl, SPORTDiscus, and Web of Science databases. The eligibility criteria for selecting studies included randomized clinical trials that compared MT versus other interventions in functional outcomes, such as thumb and/or hand function questionnaires, pinch and/or grip strength, thumb and/or hand range of motion, and pain intensity or pressure pain threshold in patients with thumb carpometacarpal OA. RESULTS: Five clinical trials met the eligibility criteria; for the quantitative synthesis, four studies were included. The mean difference (MD) for grip strength was 0.87kg (95% CI = 0.29-1.44, p = .003), for pinch strength was 0.10kg (95% CI = -0.01-0.20, p = .06), and for the pressure pain threshold was 0.64kg/cm2 (95% CI = 0.07-1.20, p = .03). All differences were in favor of the MT group. CONCLUSIONS: In the short-term, there was moderate to high evidence, with statistically significant differences in the functional outcomes, in favor of MT versus sham interventions in patients with thumb carpometacarpal OA. However, these differences are not clinically important.


Asunto(s)
Articulaciones Carpometacarpianas , Manipulaciones Musculoesqueléticas , Osteoartritis , Humanos , Pulgar , Osteoartritis/terapia , Fuerza de Pellizco , Fuerza de la Mano , Dolor
11.
Micromachines (Basel) ; 13(11)2022 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-36363850

RESUMEN

A solar cell structure with a graded bandgap absorber layer based on InGaN has been proposed to overcome early predicted efficiency. Technological issues such as carrier concentration in the p- and n-type are based on the data available in the literature. The influence of carrier concentration-dependent mobility on the absorber layer has been studied, obtaining considerable improvements in efficiency and photocurrent density. Efficiency over the tandem solar cell theoretical limit has been reached. A current density of 52.95 mA/cm2, with an efficiency of over 85%, is determined for a PiN structure with an InGaN step-graded bandgap absorption layer and 65.44% of power conversion efficiency for the same structure considering piezoelectric polarization of fully-strained layers and interfaces with electron and hole surface recombination velocities of 10-3 cm/s.

12.
Rev. chil. infectol ; Rev. chil. infectol;41(2): 259-281, abr. 2024. tab
Artículo en Español | LILACS | ID: biblio-1559681

RESUMEN

El enfrentamiento de las personas que viven con VIH es amplio y requiere dedicación en múltiples dimensiones, más allá de la terapia antirretroviral. Estas recomendaciones abordan el manejo desde el diagnóstico, primera visita, seguimiento, manejo de comorbilidades infecciosas y no infecciosas, tamizaje de neoplasias, profilaxis antimicrobiana y vacunas, entre otras.


Management of people living with HIV is broad and multiple dimensions must be considered, beyond antiretroviral therapy. These recommendations include management from diagnosis, first visit, patient follow-up, infectious and non-infectious comorbidities, malignancies screening, antimicrobial and immunizations prophylaxis, among others.


Asunto(s)
Humanos , Infecciones por VIH/diagnóstico , Infecciones por VIH/terapia , Atención Ambulatoria/normas , Chile
13.
Rev. chil. infectol ; Rev. chil. infectol;39(5): 517-524, oct. 2022. tab, graf
Artículo en Español | LILACS | ID: biblio-1431689

RESUMEN

INTRODUCCIÓN: El uso de antimicrobianos se asocia a efectos laterales como alergias, reacciones adversas específicas y emergencia de resistencia antimicrobiana. Resulta fundamental una comunicación de riesgo efectiva a la población general sobre su utilidad y potenciales problemas. Experiencias internacionales revelan un bajo grado de conocimiento en la comunidad en países sin políticas educativas dirigidas, lo que mejora tras su implementación; a nivel regional y nacional existen escasas publicaciones al respecto. OBJETIVO: Describir el grado de conocimiento y conductas sobre el uso de antimicrobianos en adultos de Santiago de Chile. MÉTODOS: Estudio transversal realizado mediante una encuesta a adultos en Santiago de Chile, evaluando cuatro aspectos sobre antimicrobianos: conocimiento, uso reciente, conductas sobre su uso y nociones sobre resistencia antimicrobiana. RESULTADOS: Se encuestaron 300 personas entre 18 y 81 años (tres fueron descartadas posteriormente), siendo 75% de ellas menores de 45 años. Un 65% de los encuestados cree que los antibióticos antimicrobianos son activos frente a virus, 51% cree que sirven para tratar el resfrío común y 32% los ha utilizado sin receta. Un 51% ha escuchado el término resistencia antimicrobiana y 33% conoce su definición correcta. CONCLUSIÓN: El conocimiento sobre la utilidad y problemas de los antimicrobianos en población chilena es deficiente, lo que podría favorecer su uso inapropiado.


BACKGROUND: Antimicrobials use is associated with diverse secondary effects, as allergies, specific adverse drug reactions and emergence of antimicrobial resistance. Effective risk communication to the general public about their uses and potential issues is critical. International experience reveals deficient knowledge in countries without educational policies regarding this issue, but their implementation can reverse such deficit. There are scarce publications at regional and national level about these topics. AIM: To describe the knowledge and behaviors regarding antimicrobial use in adults in Santiago de Chile. METHODS: We conducted a cross-sectional study through a survey in 300 people in Santiago de Chile, evaluating 4 areas about antimicrobials: knowledge, use, behaviors, and antimicrobial resistance knowledge. RESULTS: 297 people were surveyed with ages between 18 and 81 years old. Seventy-five percent of them were younger than 45 years old. 65% of the surveyed thinks antimicrobials works against viruses, 51% believes they work against the common cold and 32% of the population has used them without a prescription. Fifty-one percent of the sample has heard about antimicrobial resistance and 33% knows its correct definition. CONCLUSIONS: The Chilean population has an important deficit in antimicrobial knowledge and use.


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Adulto Joven , Farmacorresistencia Microbiana , Conocimientos, Actitudes y Práctica en Salud , Antiinfecciosos/uso terapéutico , Chile , Educación en Salud , Estudios Transversales , Encuestas y Cuestionarios , Conocimiento de la Medicación por el Paciente , Antibacterianos/uso terapéutico
14.
PLoS One ; 12(7): e0181569, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28742879

RESUMEN

Porcine reproductive and respiratory syndrome (PRRS) is endemic in most pork producing countries. In Chile, eradication of PRRS virus (PRRSV) was successfully achieved in 2009 as a result of the combined efforts of producers and the animal health authorities. In October 2013, after several years without detecting PRRSV under surveillance activities, suspected cases were confirmed on a commercial swine farm. Here, we describe the PRRS epidemic in Chile between October 2013 and April 2015, and we studied the origins and spread of PRRSV throughout the country using official surveillance data and Bayesian phylogenetic analysis. Our results indicate that the outbreaks were caused by a PRRSV closely related to viruses present in swine farms in North America, and different from the strain that circulated in the country before 2009. Using divergence time estimation analysis, we found that the 2013-2015 PRRSV may have been circulating in Chile for at least one month before the first detection. A single strain of PRRSV spread into a limited number of commercial and backyard swine farms. New infections in commercial systems have not been reported since October 2014, and eradication is underway by clearing the disease from the few commercial and backyard farms that remain positive. This is one of the few documented experiences of PRRSV introduction into a disease-free country.


Asunto(s)
Síndrome Respiratorio y de la Reproducción Porcina/epidemiología , Virus del Síndrome Respiratorio y Reproductivo Porcino/aislamiento & purificación , Crianza de Animales Domésticos , Animales , Teorema de Bayes , Chile/epidemiología , Brotes de Enfermedades , Variación Genética , Filogenia , Virus del Síndrome Respiratorio y Reproductivo Porcino/genética , Porcinos/virología
15.
Enferm Infecc Microbiol Clin ; 28(1): 66-7, 2010 Jan.
Artículo en Español | MEDLINE | ID: mdl-19419799
16.
J Air Waste Manag Assoc ; 54(8): 908-13, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15373358

RESUMEN

In the city of Santiago, Chile, air quality is defined in terms of particulate matter with an aerodynamic diameter < or = 10 microm (PM10) concentrations. An air quality forecasting model based on past concentrations of PM10 and meteorological conditions currently is used by the metropolitan agency for the environment, which allows restrictions to emissions to be imposed in advance. This model, however, fails to forecast between 40 and 50% of the days considered to be harmful for the inhabitants every year. Given that a high correlation between particulate matter and carbon monoxide (CO) concentrations is observed at monitoring stations in the city, a model for CO concentration forecasting would be a useful tool to complement information about expected air quality in the city. Here, the results of a neural network-based model aimed to forecast maximum values of the 8-hr moving average of CO concentrations for the next day are presented. Forecasts from the neural network model are compared with those produced with linear regressions. The neural network model seems to leave more room to adjust free parameters with 1-yr data to predict the following year's values. We have worked with 3 yr of data measured at the monitoring station located in the zone with the worst air quality in the city of Santiago, Chile.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monóxido de Carbono/análisis , Modelos Teóricos , Chile , Ciudades , Predicción , Tamaño de la Partícula
17.
Virology ; 440(1): 8-18, 2013 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-23523133

RESUMEN

The early steps of HIV-1 replication involve the entry of HIV-1 into the nucleus, which is characterized by viral interactions with nuclear pore components. HIV-1 developed an evolutionary strategy to usurp the nuclear pore machinery and chromatin in order to integrate and efficiently express viral genes. In the current work, we studied the role of nucleoporins 153 and 98 (Nup153 and Nup98) in infection of human Jurkat lymphocytes by HIV-1. We showed that Nup153-depleted cells exhibited a defect in nuclear import, while depletion of Nup 98 caused a slight defect in HIV integration. To explore the biochemical viral determinants for the requirement of Nup153 and Nup98 during HIV-1 infection, we tested the ability of these nucleoporins to interact with HIV-1 cores. Our findings showed that both nucleoporins bind HIV-1 cores suggesting that this interaction is important for HIV-1 nuclear import and/or integration. Distribution analysis of integration sites in Nup153-depleted cells revealed a reduced tendency of HIV-1 to integrate in intragenic sites, which in part could account for the large infectivity defect observed in Nup153-depleted cells. Our work strongly supports a role for Nup153 in HIV-1 nuclear import and integration.


Asunto(s)
VIH-1/fisiología , Proteínas de Complejo Poro Nuclear/metabolismo , Replicación Viral/fisiología , Silenciador del Gen , VIH-1/metabolismo , Humanos , Integrasas/genética , Integrasas/metabolismo , Células Jurkat , Proteínas de Complejo Poro Nuclear/genética
18.
J Alzheimers Dis ; 31(1): 65-9, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22495344

RESUMEN

Platelets are major reservoirs of circulating amyloid-ß and amyloid-ß protein precursor (AßPP) and have been postulated as a reliable source for biological markers of Alzheimer's disease (AD). We have recently demonstrated that tau is also present in platelets, and that there are differences in the electrophoretic patterns of platelet tau forms in AD subjects with respect to controls. Here, we demonstrate that modifications in platelet tau forms occur independently of age in a broad population of 104 neurologically healthy individuals. More interesting, a strong correlation of platelet markers with the degree of cognitive impairment was evidenced in a group of 47 AD patients in comparison with 19 cognitive healthy subjects. In our series, platelet tau forms ratio had a sensitivity of 75.7% and specificity of 73.7%, respectively. We also found that platelet tau displays a significantly higher correlation with the presence of AD than the analyses of platelet AßPP.


Asunto(s)
Enfermedad de Alzheimer/sangre , Enfermedad de Alzheimer/complicaciones , Trastornos del Conocimiento/sangre , Trastornos del Conocimiento/etiología , Estadística como Asunto , Proteínas tau/sangre , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Femenino , Humanos , Masculino , Escala del Estado Mental , Persona de Mediana Edad , Curva ROC
19.
PLoS One ; 7(9): e46037, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23049930

RESUMEN

The nuclear pore complex (NPC) mediates nucleo-cytoplasmic transport of macromolecules and is an obligatory point of passage and functional bottleneck in the replication of some viruses. The Human Immunodeficiency Virus (HIV) has evolved the required mechanisms for active nuclear import of its genome through the NPC. However the mechanisms by which the NPC allows or even assists HIV translocation are still unknown. We investigated the involvement of four key nucleoporins in HIV-1 docking, translocation, and integration: Nup358/RanBP2, Nup214/CAN, Nup98 and Nup153. Although all induce defects in infectivity when depleted, only Nup153 actually showed any evidence of participating in HIV-1 translocation through the nuclear pore. We show that Nup358/RanBP2 mediates docking of HIV-1 cores on NPC cytoplasmic filaments by interacting with the cores and that the C-terminus of Nup358/RanBP2 comprising a cyclophilin-homology domain contributes to binding. We also show that Nup214/CAN and Nup98 play no role in HIV-1 nuclear import per se: Nup214/CAN plays an indirect role in infectivity read-outs through its effect on mRNA export, while the reduction of expression of Nup98 shows a slight reduction in proviral integration. Our work shows the involvement of nucleoporins in diverse and functionally separable steps of HIV infection and nuclear import.


Asunto(s)
VIH-1/metabolismo , Proteínas de Complejo Poro Nuclear/metabolismo , Poro Nuclear/metabolismo , Transporte Activo de Núcleo Celular/genética , Transporte Activo de Núcleo Celular/fisiología , Infecciones por VIH/virología , VIH-1/fisiología , Células HeLa , Humanos , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Proteínas de Complejo Poro Nuclear/genética , Unión Proteica/genética , Unión Proteica/fisiología
20.
J Alzheimers Dis ; 25(1): 103-9, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21368381

RESUMEN

Platelets are a major peripheral reservoir of the amyloid-ß protein precursor, so they have been considered as a potential biological marker of Alzheimer's disease (AD). Here, it is demonstrated that tau protein is also present in platelets and that the levels of oligomeric species of this protein could serve as a novel and reliable biological marker for AD. Blood samples were obtained from 15 AD patients and 10 paired-age controls and platelets were separated via differential centrifugation. The purity of platelets was determined by flow cytometry and microscopy and the presence of tau was determined by immunofluorescence and immunoblots with tau specific antibodies. Immunofuorescence and immunoblot patterns of platelets were positive for tau. Immunoblots also showed the presence of high molecular weight (HMW) variants of tau that appeared to correspond to oligomeric forms of the protein. The ratio of HMW tau respect to tau monomeric species was significantly higher in AD patients than controls. The present is the first description of the presence of tau in platelets. The analysis of different tau fractions in platelets could serve as a new biological marker for AD.


Asunto(s)
Enfermedad de Alzheimer/sangre , Enfermedad de Alzheimer/diagnóstico , Plaquetas/metabolismo , Proteínas tau/sangre , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recuento de Plaquetas/métodos
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