3,152 research outputs found

    Enfermedad de Alzheimer y degeneración macular asociada a la edad

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    [Resumen] Objetivos: Analizar diferentes factores de riesgo implicados en la aparición de la enfermedad de Alzheimer y de la degeneración macular asociada a la edad, tratando de establecer una relación de asociación entre ambas entidades. Métodos: Sobre una muestra de 57 sujetos, de los que 33 presentan demencia (casos) y 24 no (controles) se realiza estudio analítico a fin de establecer el grado de asociación entre la enfermedad de Alzheimer (EA) y la degeneración macular asociada a la edad (DMAE). Para ello, tras realizar anamnesis a todos los sujetos, se estudia el fondo de ojo mediante cámara no midriática tipo Topcon TRV-50VT. Resultados: De acuerdo a la hipótesis de trabajo planteada, aplicada la razón de productos cruzados o de disparidad (odds ratio) se obtuvo un resultado positivo que determina relación causa efecto, ya que el porcentaje de casos con DMAE (42,4%) es superior al de controles con DMAE (25%). Por otro lado mediante la Chi cuadrado de Pearson, aunque no se establecieron diferencias significativas, los datos obtenidos muestran protección en el grupo control de acuerdo al estadístico exacto de Fisher (p=0,649). Conclusiones: Existen evidencias suficientes para pensar que la EA y la DMAE podrían tener factores etiológicos y patogénicos comunes, y aunque en nuestro estudio no hemos podido establecer la relación significativa entre ambas patologías, posiblemente en base al tamaño de la muestra o a las diferencias de edades entre ambos grupos, creemos establecida la posible asociación como para plantear un futuro trabajo que pueda confirmar estos hallazgos.[Abstract] Objectives: We analysed different risk factors involved in the onset of both Alzheimer’s disease (AD) and age-related macular degeneration (ARMD). The putative relation between both disorders was studied. Methods: We studied 57 subjects to determine the correlation between AD and ARMD. Thirty-three of the subjects suffered dementia (cases), whereas 24 of them (controls) did not. Firstly, anamnesis was performed for all individuals. We then examined the macular area of the eye using a non-midriatic TRV-50VT fundus camera. Significant odds ratio (OR) results were used as a statistical tool to survey the putative link between AD and ARMD. Results: The OR test results showed that ARMD was associated with Alzheimer’s disease. The occurrence of ARMD was significantly higher for cases (42.4%) than for controls (25%). On this basis, we inferred a cause-effect relation linking both variables. Our dataset suggested that the control group was more protected against ARMD than the case group, as revealed by Fisher’s exact test (P = 0.649). However, such a difference between both groups was not strongly supported. Conclusions: We suggest that AD and ARMD may have common factors concerning etiology and pathogenesis. Our dataset did not allow us to show a significant relation between both disorders, which is likely due to sample size and/or to age differences in the two studied groups. Even so, we feel that the possibility of such an association is justified, and future surveys to test this possibility are warranted

    Regional-scale vegetation heterogeneity in northeastern Patagonia: Environmental and spatial components

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    Our aim was to describe vegetation heterogeneity at a regional scale in northeastern Patagonia and to identify the environmental variables associated to it. The study area encompasses 13 144 km2 and is characterized by a mixture of species typical of Patagonian steppes and Monte Desert. We performed 48 vegetation relevés, which were randomly assigned to a training set and to a validation set (32 and 16 relevés, respectively). Training set was subjected to cluster analysis, which allowed the identification of two plant communities one related to Patagonian steppes and another to the Monte desert. We derived 3 attributes of the seasonal curve of the NDVI as indicators of ecosystem function: the seasonal amplitude (SA), the date of the maximum (DOM), and the large seasonal integral (LSI). We explored the relationship between NDVI attributes and communities by classification tree analysis. LSI was the strongest predictor among NDVI attributes, separating both communities without misclassification errors. Patagonian steppes occupy areas with higher LSI. The partial RDA analysis explained 38.1% of total data variation, of which 16.5% was ascribed to environment, 7.9% to space, and 13.7% to spatial component of environment. Patagonian steppes are closer to the coast, in areas exhibiting higher annual precipitation and lower annual temperature range than Monte deserts. Our results indicate the occurrence of two plant communities in the study area and highlight the significance of climatic variables to explain their spatial distribution. As most scenarios of future climate predict greater annual thermal amplitude in the study area, the limit between both communities could be displaced eastward

    Direct analysis of olive oil and other vegetable oils by mass spectrometry: a review

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    Virgin olive oil (VOO) is a highly valued vegetable oil often subjected to fraud practices such as adulteration with lower prized oils such as seed oils and refined olive oil. Thus, there is a need to provide rapid tools that allow high-throughput authentication and quality control of VOO as well as other valued oils. Mass spectrometry offers unique features -such as specificity, sensitivity and speed of analysis-that map well against this challenge, either those based on atmospheric pressure ionization methods (ESI and APCI) or those occurring under vacuum conditions such as MALDI for nonvolatile species or headspace sampling-mass spectrometry using electron impact ionization (HS-MS) or chemical ionization (proton transfer reaction mass spectrometry (PTR-MS) and selected ion flow tube mass spectrometry (SIFT-MS)) for volatile fraction analysis. In addition, more recent atmospheric pressure methods (Ambient MS) enable direct analysis with minor or even no sample manipulation. The aim of this article is to provide a critical overview on all these methods and their potential use for vegetable oil characterization, highlighting the strengths and weaknesses of the differentMarie Sklodowska-Curie (MSCA) grant agreement number 840743, EU FEDER funds and the Research Programme of the University of Jaen (Plan 2019–2020, Research programme “Acción 10”) and Regional Government of Andalucía, Spain (Project Ref. PY2018-1211)

    Therapeutic Drug Monitoring of Antifungal Drugs: Another Tool to Improve Patient Outcome?

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    Introduction: This study aimed to examine the relationship among adequate dose, serum concentration and clinical outcome in a non-selected group of hospitalized patients receiving antifungals. Methods: Prospective cross-sectional study performed between March 2015 and June 2015. Dosage of antifungals was considered adequate according to the IDSA guidelines, whereas trough serum concentrations (determined with HPLC) were considered adequate as follows: fluconazole > 11\ua0\ub5g/ml, echinocandins > 1\ua0\ub5g/ml, voriconazole 1\u20135.5\ua0\ub5g/ml and posaconazole > 0.7\ua0\ub5g/ml. Results: During the study period, 84 patients (65.4% male, 59.6\ua0years) received antifungals for prophylaxis (40.4%), targeted (31.0%) and empirical therapy (28.6%). The most frequent drug was micafungin (28/84; 33.3%) followed by fluconazole (23/84; 27.4%), voriconazole (15/84; 17.9%), anidulafungin (8/84; 9.5%), posaconazole (7/84; 8.3%) and caspofungin (3/84; 3.6%). Considerable interindividual variability was observed for all antifungals with a large proportion of the patients (64.3%) not attaining adequate trough serum concentrations, despite receiving an adequate antifungal dose. Attaining the on-target serum antifungal level was significantly associated with a favorable clinical outcome (OR = 0.02; 95% CI 0.01\u20130.64; p = 0.03), whereas the administration of an adequate antifungal dosage was not. Conclusions: With the standard antifungal dosage, a considerable proportion of patients have low drug concentrations, which are associated with poor clinical outcome

    Differences in the robustness of clusters involving the Mycobacterium tuberculosis strains most frequently isolated from immigrant cases in Madrid

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    AbstractTuberculosis cases infected by the same Mycobacterium tuberculosis (MTB) strain are considered to be clustered and involved in a transmission chain. Large clusters are assumed to represent active transmission chains in a population. In the present study, we focused on the analysis of large clusters defined by IS6110-restriction fragment length polymorphism (RFLP) typing in the immigrant population in Madrid. We identified 12 large clusters (involving 43% of the isolates) comprising 4–23 representatives. We proposed a gradient of epidemiological certainty for these large clusters. For a cluster to be considered robust and a good indicator of recent transmission, the MTB strain involved should not have been identified in a geographically and epidemiologically unrelated population and the cluster had to be re-confirmed by another highly discriminative molecular marker (MIRU-VNTR). The clusters that we discovered were classified into three categories: high, intermediate and low expected epidemiological value. In the largest cluster in the study (cluster M6; 23 representatives), failures by both criteria were identified: the representative seven-band RFLP pattern was also the most prevalent in the unrelated population (25 cases) and the cluster was fully split by MIRU-15, suggesting a lack of epidemiological value. The RFLP pattern representative of this cluster was also identified in 64 isolates from five countries in the Latin American genotype database, and again proved to be heterogeneous according to the MIRU-15 analysis. Specific analysis of large clusters, combined with the application of criteria for evaluating their robustness, could help identify uninformative clusters and target epidemiological resources towards those clusters with higher expected epidemiological value
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