35 research outputs found

    Pregerminative treatments in Tillandsia ionantha seeds to obtain seedlings under in vitro culture

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    Objective: To search for an in vitro strategy to favor both germination and a greater number of seedlings in Tillandsia ionantha; also, to promote the development of future research on this species. Design/methodology/approach: Factor one: lighting conditions (light-dark), factor two: 13 preconditioning treatments, which included storage at room temperature and in refrigeration at 10° C, soaking (12 and 24 hours), with hydrogen peroxide (10 and 20 %), potassium nitrate (0.2 and 0.4 %), gibberellins (50 and 150 ml.l-1), three alternate incubation temperatures (28, 32 and 36 °C). They were sown in MS medium (Murashige and Skoog, 1962) at 25 %, adding 20 g.l-1 of sugar, 2 g.l-1 of activated carbon, and 5 .5 g.l-1 of agar. A flask with three seeds which coma removed was established as an experimental unit; 15 repetitions were established and placed in the incubation room at 24 °C with a photoperiod of 16:8. The germination process was recorded, and the seedlings were extracted two months after their establishment. Results: The treatment that resulted in the highest number of seeds that initiated the germination process and the highest number of plants was when the seeds were kept at room temperature. The highest contamination was observed in the treatment exposed to 32 °C. It was observed that 80% of the experimental units showed signs of imbibition within a few days, although the vast majority did not complete the process and the maximum yield was on average 1.4 seedlings. Conclusions: The best treatment is to use seeds stored at room temperature and if storage is necessary, to soak them for 12 h

    Human Immunodeficiency Virus/Hepatits C Virus Coinfection in Spain: Elimination Is Feasible, but the Burden of Residual Cirrhosis Will Be Significant

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    Background: We assessed the prevalence of antibodies against hepatitis C virus (HCV-Abs) and active HCV infection in patients infected with human immunodeficiency virus (HIV) in Spain in 2016 and compared the results with those of similar studies performed in 2002, 2009, and 2015. Methods: The study was performed in 43 centers during October-November 2016. The sample was estimated for an accuracy of 2% and selected by proportional allocation and simple random sampling. During 2016, criteria for therapy based on direct-acting antiviral agents (DAA) were at least significant liver fibrosis, severe extrahepatic manifestations of HCV, and high risk of HCV transmissibility. Results: The reference population and the sample size were 38904 and 1588 patients, respectively. The prevalence of HCV-Abs in 2002, 2009, 2015, and 2016 was 60.8%, 50.2%, 37.7%, and 34.6%, respectively (P trend <.001, from 2002 to 2015). The prevalence of active HCV in 2002, 2009, 2015, and 2016 was 54.0%, 34.0%, 22.1%, and 11.7%, respectively (P trend <.001). The anti-HCV treatment uptake in 2002, 2009, 2015, and 2016 was 23.0%, 48.0%, 59.3%, and 74.7%, respectively (P trend <.001). In 2016, HCV-related cirrhosis was present in 7.6% of all HIV-infected individuals, 15.0% of patients with active HCV, and 31.5% of patients who cleared HCV after anti-HCV therapy. Conclusions: Our findings suggest that with universal access to DAA-based therapy and continued efforts in prevention and screening, it will be possible to eliminate active HCV among HIV-infected individuals in Spain in the short term. However, the burden of HCV-related cirrhosis will continue to be significant among HIV-infected individuals.This work was funded by grant Ref. no. GLD14-00279 from the GILEAD Fellowship Programme (Spain) and by the Spanish AIDS Research Network (RD16/0025/0017, RD16/0025/0018) that is included in the Spanish I+D+I Plan and is co-financed by ISCIII-Subdirección General de Evaluacion and European Funding for Regional Development (FEDER).S

    Relationships between heavy metal concentrations in three different body fluids and male reproductive parameters: a pilot study

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    <p>Abstract</p> <p>Background</p> <p>Animal studies have shown the reproductive toxicity of a number of heavy metals. Very few human observational studies have analyzed the relationship between male reproductive function and heavy metal concentrations in diverse biological fluids.</p> <p>Methods</p> <p>The current study assessed the associations between seminal and hormonal parameters and the concentration of the 3 most frequent heavy metal toxicants (lead, cadmium and mercury) in three different body fluids. Sixty one men attending infertility clinics that participated in a case-control study to explore the role of environmental toxins and lifestyles on male infertility were analyzed. Concentration of lead, cadmium and mercury were measured in blood and seminal plasma and whole blood using anodic stripping voltammetry and atomic absorption spectrophotometry. Serum samples were analyzed for follicle-stimulating hormone, luteinizing hormone and testosterone. Semen analyses were performed according to World Health Organization criteria. Mann-Whitney test and Spearman's rank correlations were used for unadjusted analyses. Multiple linear regression models were performed controlling for age, body mass index and number of cigarettes per day.</p> <p>Results</p> <p>There were no significant differences between cases and controls in the concentrations of heavy metals in any of the three body fluids. In multivariate analyses using all subjects no significant associations were found between serum hormone levels and metal concentrations. However there was a significant positive association between the percentage of immotile sperms and seminal plasma levels of lead and cadmium.</p> <p>Conclusions</p> <p>Our results suggest that the presence of lead and cadmium in the reproductive tract of men may be related to a moderate alteration of their seminal parameters.</p

    Lo glocal y el turismo. Nuevos paradigmas de interpretación.

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    El estudio del turismo se realiza desde múltiples escalas y enfoques, este libro aborda muchos temas que es necesario discutir desde diversas perspectivas; es el caso de la reflexión sobre la propia disciplina y sus conceptos, así como los asuntos específicos referidos al impacto territorial, los tipos de turismo, las cuestiones ambientales, el tema de la pobreza, la competitividad, las políticas públicas, el papel de las universidades, las áreas naturales protegidas, la sustentabilidad, la cultura, el desarrollo, la seguridad, todos temas centrales documentados y expuestos con originalidad y dominio del asunto. Lo multiescalar es básico para la comprensión del sistema turístico, sistema formado de procesos globales, regionales y locales. El eje de discusión del libro es lo glocal, esa interacción entre lo nacional y local con lo global

    Epidemiological trends of HIV/HCV coinfection in Spain, 2015-2019

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    Altres ajuts: Spanish AIDS Research Network; European Funding for Regional Development (FEDER).Objectives: We assessed the prevalence of anti-hepatitis C virus (HCV) antibodies and active HCV infection (HCV-RNA-positive) in people living with HIV (PLWH) in Spain in 2019 and compared the results with those of four similar studies performed during 2015-2018. Methods: The study was performed in 41 centres. Sample size was estimated for an accuracy of 1%. Patients were selected by random sampling with proportional allocation. Results: The reference population comprised 41 973 PLWH, and the sample size was 1325. HCV serostatus was known in 1316 PLWH (99.3%), of whom 376 (28.6%) were HCV antibody (Ab)-positive (78.7% were prior injection drug users); 29 were HCV-RNA-positive (2.2%). Of the 29 HCV-RNA-positive PLWH, infection was chronic in 24, it was acute/recent in one, and it was of unknown duration in four. Cirrhosis was present in 71 (5.4%) PLWH overall, three (10.3%) HCV-RNA-positive patients and 68 (23.4%) of those who cleared HCV after anti-HCV therapy (p = 0.04). The prevalence of anti-HCV antibodies decreased steadily from 37.7% in 2015 to 28.6% in 2019 (p < 0.001); the prevalence of active HCV infection decreased from 22.1% in 2015 to 2.2% in 2019 (p < 0.001). Uptake of anti-HCV treatment increased from 53.9% in 2015 to 95.0% in 2019 (p < 0.001). Conclusions: In Spain, the prevalence of active HCV infection among PLWH at the end of 2019 was 2.2%, i.e. 90.0% lower than in 2015. Increased exposure to DAAs was probably the main reason for this sharp reduction. Despite the high coverage of treatment with direct-acting antiviral agents, HCV-related cirrhosis remains significant in this population

    Tissue culture of ornamental cacti

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    Determinación de la edad de transición de madera juvenil a madura en Pinus patula SCHL. et CHAM.

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    Con el propósito de comparar diferentes criterios para estimar la edad de transición en la formación de madera juvenil a madura en una plantación de 16 años de edad de Pinus patula, se identificó el patrón radial de la proporción de madera tardía, de la densidad de la madera y de la longitud de traqueidas en una muestra de 100 árboles. De cada árbol se obtuvo una muestra de madera con un taladro de incremento a 50 cm de altura del tronco. La proporción de madera tardía presentó un aumento gradual hasta los 14 años y después se apreció un aumento más rápido; la densidad de la madera presentó un decremento en los primeros años y posteriormente mostró un incremento gradual, estabilizándose a los 12-14 años de edad. La longitud de traqueidas mostró un patrón más estable, aumentando progresivamente desde el centro hasta estabilizarse a los 8-10 años de edad. Un análisis de regresión segmentada utilizando los valores anuales promedio de la longitud de traqueidas y densidad de la madera mostraron que la edad de transición de madera juvenil a madura ocurrió a los 10 años en esta plantación. El criterio basado en la longitud de traqueidas fue más útil, ya que presentó un cambio de pendiente más evidente. Con base en este criterio se encontró una amplia variación entre árboles en la edad de transición (de 6 a 16 años), que podría estar asociada a efectos genéticos; sin embargo, se requiere un mayor tamaño de muestra para estimar la variación genética en esta característica. Palabras clave: Calidad de la madera, densidad de la madera, formación de madera, longitud de traqueidas, patrón radial, proporción de madera tardía, regresión segmentada
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