Repositorio académico de acceso abierto (Univ. Autonóma de Chile)
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Efficacy of risdiplam in spinal muscular atrophy: A systematic review and meta-analysis
No full textThis systematic review and meta-analysis aimed to assess the efficacy and safety of risdiplam on motor and respiratory function in spinal muscular atrophy (SMA). We systematically searched Medline, Scopus, Web of Science, and the Cochrane Library from inception to March 2023. We included pre-post studies that determined the effect of risdiplam on the Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP-INTEND), the 32-item Motor Function Measure (MFM32), the Revised Upper Limb Module (RULM), the Hammersmith Functional Motor Scale – Expanded (HFMSE), respiratory function, and the proportion of risdiplam-related adverse events in a population with SMA (phenotypes 1 and 2/3). Meta-analyses were also performed where possible. Eleven studies were included. After 12 months of treatment, 57% of participants with SMA1 achieved a CHOP-INTEND score ≥ 40 points, and more than half were able to feed orally and had head control. In SMA2/3, MFM32, RULM, and HFMSE increased by 2.09 (1.17, 3.01), 1.73 (1.25, 2.20), and 1.00 (0.40, 1.59) points, respectively. Efficacy on respiratory function in SMA2/3 was inconsistent. Finally, 16% of participants experienced adverse events, but serious adverse events could not be quantified due to a lack of cases. The limited available evidence suggests that risdiplam is an effective and safe drug for the treatment of SMA. In addition, long-term clinical benefit may be partly determined by the stage of disease at which treatment is initiated. © 2023 The Authors. Pharmacotherapy: The Journal of Human Pharmacology and Drug Therapy published by Wiley Periodicals LLC on behalf of Pharmacotherapy Publications, Inc.Universidad de Castilla-La Mancha, UCLM, (2018‐CPUCLM‐7939)Universidad Autónoma de Chil
Sperm Conjugates (Association of Several Sperm in the Epididymis) Reach Zone Fertilization in Rats, but Fertilizes Only One Sperm
No full textMammalian sperm con jugation phenomenon occurs both in the epididymis or post ejaculation. Sperm conjugates consist of tens to hundreds of partner sperm. The combination of sperm is found in the ejaculate of some species but it is unknown if the female tract amount reaching the área of ??fertilization (distal third of the tubes) and if the dissociation before or during interaction with the oocyte cumulus. Various mechanisms have been proposed by which the formation of these structures favor fertilization: a. increased speed of scrolling synergies with individual sperm, particularly in cases of sperm, b competition. conjugated sperm protection against the hostile environment, c. prevention of early acrosome reaction, among others. Our group described this phenomenon in rat and mouse rosettes and proposed calling them a possible associative mechanism. These conjugates consist of groups of sperm joined at their heads and with their free scourges in no less than 10 cells. They were described within the lumen of the region of the cauda epididymis, but not in more proximal sites, suggesting that sperm join together must have matured and made contact with factors of epididymal fluid. To know what the final destination of the spermatic conjugates we studied the presence of male gametes conjugate or in the female genital tract after ejaculation rat. Samples of the contents of the tubes obtained different times allowed us to observe mating post near the complex conjugates cumulus - oocyte. But only individual sperm between the cumulus cells were observed. This suggests that the conjugates after reaching sperm fertilization area are separated into individual sperm
Planificación Estratégica en las Empresas de Construcción y Montaje Prestadoras de Servicios al Sector Petrolero
No full textLa investigación se planteó como objetivo analizar la planificación estratégica en las empresas de construcción y montaje prestadoras de servicios al sector petrolero. Sustentando en los autores: David (2013), D`Alessio (2013), Carucci (2011), entre otros. Metodológicamente se concibe dentro del paradigma cuantitativo, enfoque positivista, tipología analítica, diseño en fuente viva, perspectiva temporal transeccional contemporánea, amplitud asociada a dos eventos. La población se conformó por las 6 empresas del sector activas ante la Cámara Petrolera de Venezuela Capítulo Zulia; adquiriendo la característica de censo poblacional; como unidades informantes se seleccionaron los 8 principales gerentes de las organizaciones. Para colectar la información se recurrió al uso de la entrevista como técnica, como instrumento se diseñó un cuestionario estructurado bajo la escala Likert con 5 opciones de respuesta; para su elaboración se recurrió a la escala de actitud donde se hace presente el cero absoluto como opción de no presencia del atributo a medir. Para la validación se recurrió al arbitraje de 5 expertos, para determinar la confiabilidad se aplicó una prueba piloto a 3 empresas del mismo sector, pero no pertenecientes a la población con 5 unidades informantes, obteniendo un resultado de 0,80. La técnica de procesamiento y análisis de los datos fue la estadística descriptiva, aplicando el nivel de escala de razón a través de la determinación de: media armónica, coeficiente de asimetría Fisher y curtosis. Los resultados permitieron demostrar que en el actual escenario país, la planificación estratégica es una herramienta efectiva para armonizar los resultados organizacionales
La situación fiscal de las ciudades argentinas
No full textLas ciudades argentinas (y sus gobiernos locales) en las últimas décadas han sufrido profundas transformaciones en materia de funciones de gasto. Se han ampliado y complejizado sus actividades, y en muchas ocasiones, sin contar con los recursos financieros suficientes para hacer frente a las mismas.
El nivel de dependencia financiera que poseen de los gobiernos de superior jerarquía (Nación y provincias) es muy elevado. Modificar este aspecto, junto a otros asuntos relativos al financiamiento municipal, es un aspecto clave para dotar a los gobiernos locales argentinos de un más amplio espacio de intervención fiscal que permita reducir su dependencia de las transferencias de otras jurisdicciones, para con todo ello, obtener una provisión pública local de bienes y servicios, con un piso de homogeneidad en términos de calidad, cantidad y accesibilidad, en todo el territorio nacional
Effects of alpha-tocopherol antioxidant on fracture strength and adhesion of endodontically treated teeth restored after dental bleaching
No full textThis study evaluated the effect of different concentrations of alpha-tocopherol in gel form on fracture strength, hybrid layer formation, and microtensile bond strength of endodontically treated teeth bleached with 40% hydrogen peroxide (H2O2). Sixty bovine incisors were randomized into one of six groups (n = 10 incisors per group) defined by the interventions carried out after endodontic treatment. In the control group, no additional intervention was carried out, while all teeth in the five intervention groups were bleached with 40% H2O2 and subsequently treated with alpha-tocopherol at concentrations of 15% (15AT), 20% (20AT), or 25% (25AT), with 10% sodium ascorbate (10SA), or with nothing (40HP). Fracture strength was evaluated in a mechanical testing machine, hybrid layer formation was assessed using scanning electron microscopy, and bond strength was determined using microtensile bond-strength testing. Data were analyzed using Kruskal–Wallis and Dunn's tests. No statistically significant difference regarding fracture strength was observed among groups. Hybrid layer formation was greater in the 15AT group than in groups 40HP and 10SA. Teeth in groups 15AT, 20AT, and 25AT demonstrated higher bond strength than teeth in groups 40HP and 10SA. Alpha-tocopherol, preferably at 15%, effectively reverses the deleterious effects, of bleaching, on hybrid layer formation and bond strength to dentin. © 2023 Scandinavian Division of the International Association for Dental Research. Published by John Wiley & Sons Ltd.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, CAPE
RESEÑA DEL LIBRO "FINANCIAMIENTO DE INFRAESTRUCTURA URBANA: CRITERIOS PARA UN MODELO DE GESTIÓN PÚBLICO- PRIVADO"
No full textEffectiveness of high-intensity interval training on peripheral brain-derived neurotrophic factor in adults: A systematic review and network meta-analysis
No full textBackground: High-intensity interval training (HIIT) has emerged as an alternative training method to increase brain-derived neurotrophic factor (BDNF) levels, a crucial molecule involved in plastic brain changes. Its effect compared to moderate-intensity continuous training (MICT) is controversial. We aimed to estimate, and to comparatively evaluate, the acute and chronic effects on peripheral BDNF levels after a HIIT, MICT intervention or a control condition in adults. Methods: The CINAHL, Cochrane, PubMed, PEDro, Scopus, SPORTDiscus, and Web of Science databases were searched for randomized controlled trials (RCTs) from inception to June 30, 2023. A network meta-analysis was performed to assess the acute and chronic effects of HIIT versus control condition, HIIT versus MICT and MICT versus control condition on BDNF levels. Pooled standardized mean differences (SMDs) and their 95% confidence intervals (95% CIs) were calculated for RCTs using a random-effects model. Results: A total of 22 RCTs were selected for the systematic review, with 656 participants (aged 20.4–79 years, 34.0% females) and 20 were selected for the network meta-analysis. Network SMD estimates were significant for HIIT versus control condition (1.49, 95% CI: 0.61, 2.38) and MICT versus control condition (1.08, 95% CI: 0.04, 2.12) for acutely BDNF increase. However, pairwise comparisons only resulted in a significant effect for HIIT versus control condition. Conclusions: HIIT is the best training modality for acutely increasing peripheral BDNF levels in adults. HIIT may effectively increase BDNF levels in the long term. © 2023 The Authors. Scandinavian Journal of Medicine & Science In Sports published by John Wiley & Sons Ltd.European Social Fund, ESF, (2020‐PREDUCLM‐16746); Universidad de Castilla-La Mancha, UCLMUniversidad Autónoma de Chil
Furfural adsorption on V2O5 surface: A combined experimental-theoretical study
No full textThe adsorption of furfural on the V2O5 surface was investigated using experimental and theoretical methods. In situ Diffuse Reflectance Infrared Fourier-Transform Spectroscopy results show the presence of physi- and chemi-sorption phenomena, where trans-furfural is mostly chemisorbed at the beginning of the adsorption process. These results are in agreement with theoretical DFT results, as the most thermodynamically favored configurations corresponds to the chemisorbed trans-furfural (T1) and cis-furfural (C1) with binding energies of −1.83 and −2.05 eV. © 2024 Elsevier B.V.Fondo Nacional de Desarrollo Científico y Tecnológico, FONDECYT, (1231194, ANID/FONDAP/ 1523A0006, 1241917, ACT210057, 3230141); Fondo Nacional de Desarrollo Científico y Tecnológico, FONDECY
Biomass-derived graphene and nanostructured carbons: A review for electrochemical applications
No full textCarbon is the most promising material today. Biomass-residues are carbon-rich and have the possibility to replace obsolete, expensive and pollutant raw sources. For instance, graphene-like materials have attracted a powerful attention since its discovery. The varied textural properties, porosity, surface chemical functionality and conductivity make these biomass-derived materials ubiquitous to be used in solar cells, supercapacitors, and electrochemical sensors, among many other applications. The objective of the review is to summarize the advances in energy conversion, storage, and electrochemical sensing technologies using nanocarbons prepared from biomass. In this work we intend to correlate the nature of the graphene- or carbon-like material and its use in the different electrochemical applications mentioned. A discussion on the properties that define the effectiveness of a supercapacitor in energy storage is also proposed. The projections and future challenges in solar cells, supercapacitors and electrochemical sensors technology are also presented. © 2023 Elsevier B.V.ANID-FONDECYT, (1220228, ANID-FONDEF ID23I10085
Autocontrol y Agresión Reactiva en Adolescentes Mexicanos
No full textReactive and proactive aggression are two of the main types of aggression identified in bullying. Some research suggests that self-control contributes to a decrease in proactive and reactive aggression. However, studies that have investigated the relationships of these variables with self-control in the Mexican context are scarce. The aim of this study was to explore the relationships between self-control with reactive and proactive aggression in Mexican adolescents. The sample was selected in a non-probabilistic way, the participants in this study were 300 adolescents with ages between 12 and 18 (M age = 14, SD = 1.55), 147 (49 %) were male, while 153 (51 %) were female. Self-control was measured with the subscale Values in Action Inventory of Strengths (VIA-Youth; Park & Peterson, 2006), for reactive and proactive aggression we use the Reactive and Proactive Aggression Questionnaire (QRP; Raine et al., 2006). Results indicate that self-control was negatively and significantly related to reactive and proactive aggression. This may indicate that adolescents with a higher level of self-control have a lower frequency of proactive aggression. this study contributes to understand the different types of aggression in school bullying in adolescents. In addition, the results suggest that self-control may decrease peer aggression.La agresión reactiva y proactiva son dos de los principales tipos de agresión que se identifican en el acoso escolar. Algunas investigaciones sugieren que el autocontrol contribuye a la disminución de la agresión proactiva y reactiva; sin embargo, son escasos los estudios que han indagado en las relaciones de estas variables con el autocontrol en el contexto mexicano.El presente estudio tuvo como objetivo explorar las relaciones entre el autocontrol con la agresión reactiva y proactiva en adolescentes mexicanos. La muestra se seleccionó de forma no probabilística, participaron 300 adolescentes con edades entre 12 y 18 años (M edad = 14 años, DE = 1.55), 147 (49 %) del sexo masculino y 153 (51 %) del femenino. El autocontrol se midió con la subescala del instrumento Values in Action Inventory of Strengths (VIA-Youth; Park & Peterson, 2006), para la agresión reactiva y proactiva se utilizó el Cuestionario de Agresión Reactiva y proactiva (QRP; Raine et al., 2006). Se encontró que el autocontrol se relacionó de manera negativa y significativa con la agresión reactiva y proactiva. Estos resultados podrían indicar que, los adolescentes que tienen un mayor nivel de autocontrol, presentan menor frecuencia de agresión proactiva. El presente contribuye a la compresión de los distintos tipos de agresión en el acoso escolar en adolescentes. Además, los resultados sugieren que el autocontrol pudiera disminuir la agresión entre pare