Concentraciones séricas de 25-hidroxivitamina D y su relación con la resistencia a la insulina en muestras con valores conocidos de hemoglobina glicosilada en el Laboratorio Synlab - Sede Central, Lima 2020

El presente estudio es de tipo descriptivo-correlacional, las muestras fueron recuperadas de la seroteca del Laboratorio Synlab, determinándose niveles séricos de vitamina D, glucosa y péptido C en todas. Posteriormente se evaluó la correlación entre los niveles séricos de 25(OH)-vitamina D y HOMA-2 a través de la prueba de rango de Spearman; se consideró significativa una p < 0.05. Al evaluar la correlación entre los índices de HOMA2 en las muestras, se observó una correlación inversa (r= -0.995; p< 0.0001) entre la resistencia a la insulina (HOMA2-IR) y la sensibilidad a la insulina (HOMA2 %S), sin embargo no se observó correlación (r= 0.125; p= 0.217) entre la resistencia a la insulina y la función de células β (HOMA2 %β). Al realizar el análisis de correlación de Spearman entre los niveles de vitamina D según categoría de suficiencia y los componentes del HOMA2 (HOMA2-IR, HOMA2 %β, HOMA2 %S), no se encontró correlaciones significativas. Además, al estudiar la alteración de funcionalidad de células beta debido a la disminución de vitamina D, a través de la correlación de péptido C y HOMA2 %β, solo se encontró correlación positiva de estas variables en pacientes insuficientes y suficientes de vitamina D (p< 0.05), pero no se encontró correlación en el grupo de deficientes (p=0.462). No se encontró correlación significativa entre los niveles de vitamina D y la resistencia a la insulina

Determinación de fenoles totales y orto cresol en orina, evaluación de factores de riesgo en sujetos expuestos a benceno y tolueno de la Universidad Nacional “Diego Quispe Tito” del Cusco. Junio-diciembre 2017

En el presente trabajo se realizó la determinación de los niveles de fenoles totales y orto cresol en orina y los factores de riesgo químico asociados en sujetos expuestos de la Universidad Nacional Diego Quispe Tito a benceno y tolueno. La metodología de la investigación es diseño no experimental de tipo descriptivo, correlacional, transversal, prospectivo realizado entre Junio-Diciembre del 2017. La cuantificación de orto cresol y fenoles totales en orina fue realizado mediante la técnica de cromatografía de Líquidos de Alta Resolución y se buscó relación con los factores de riesgo químico por medio de una entrevista semiestructurada con preguntas cerradas y abiertas. La población total fue de 351 sujetos y por criterio de selección quedaron 110 para la realización del estudio, donde se encontró que el 10.9% del grupo expuesto a benceno presentó niveles de fenoles totales mayores a los permitidos según la Asociación española de toxicología (Índice de Exposición Biológica: menor a 20mg/L) y el 60% del grupo expuesto a tolueno presento niveles de orto cresol mayores a los permitidos según la Conferencia Americana de Higienistas Industriales Gubernamentales (Índice de Exposición Biológica: menor a 0.5mg/L); mientras que el grupo no expuesto presentó 85.5% niveles bajos y 3.6% no detectables de fenoles totales y 40% niveles bajos de orto cresol. Se asoció que el factor de riesgo que influye es: que a mayor duración de exposición (horas), mayor concentración de fenoles totales y orto cresol por parte de la población expuesta a benceno y tolueno de la Universidad Nacional Diego Quispe Tito

Cloning and expression analysis of the Ccrboh gene encoding respiratory burst oxidase in Citrullus colocynthis and grafting onto Citrullus lanatus (watermelon)

A full-length drought-responsive gene Ccrboh, encoding the respiratory burst oxidase homologue (rboh), was cloned in Citrullus colocynthis, a very drought-tolerant cucurbit species. The robh protein, also named NADPH oxidase, is conserved in plants and animals, and functions in the production of reactive oxygen species (ROS). The Ccrboh gene accumulated in a tissue-specific pattern when C. colocynthis was treated with PEG, abscisic acid (ABA), salicylic acid (SA), jasmonic acid (JA), or NaCl, while the homologous rboh gene did not show any change in C. lanatus var. lanatus, cultivated watermelon, during drought. Grafting experiments were conducted using C. colocynthis or C. lanatus as the rootstock or scion. Results showed that the rootstock significantly affects gene expression in the scion, and some signals might be transported from the root to the shoot. Ccrboh in C. colocynthis was found to function early during plant development, reaching high mRNA transcript levels 3 d after germination. The subcellular location of Ccrboh was investigated by transient expression of the 35S::Ccrboh::GFP fusion construct in protoplasts. The result confirmed that Ccrboh is a transmembrane protein. Our data suggest that Ccrboh might be functionally important during the acclimation of plants to stress and also in plant development. It holds great promise for improving drought tolerance of other cucurbit species

Análisis de la responsabilidad social universitaria

196 Páginas.El Global Reporting Initiative y la Guía ISO 26000, que orientan la discusión sobre responsabilidad social a nivel mundial, sostienen que sus principios son aplicables a cualquier tipo de organización. El objetivo es evidenciar si las universidades acreditadas en Colombia (PEI) se están apropiando de los conceptos organizacionales para definir sus lineamientos de responsabilidad social universitaria. Fue una investigación de tipo documental, donde se establecieron categorías a partir del marco teórico que incluían definiciones propias de la universidad, como institución social y organización. En los resultados se observó que la mayoría de universidades mantienen criterios propios como institución educativa, solo el 8,5% de las categorías relacionadas con los fines necesarios sociales tienen afinidad con las categorías de responsabilidad social organizacional

Effects of pH and vanadium concentration during the impregnation of Na-SiO2 supported catalysts for the oxidation of propane

SiO2 supported NaVOx catalysts have raised interest due to reports showing an increase in the selectivity to propene in propane oxidation; a process that may become an alternative to conventional petrochemical routes for producing this valuable olefin. In this work, the effects of pH, the concentration of vanadium in solution, [V]Sol, and of their interaction; i.e., non-additive effect, over the properties of Na-SiO2 used for the oxidation of propane under oxygen rich conditions were studied. In general, the studied experimental factors had no net effects over the difference between the nominal and final loadings of vanadium in the catalysts, the surface area, and porosity. However, all catalysts presented a ~50% decrease in surface area due to partial mesopore blocking reflected by a ~30% increase in the average pore diameter. On the other hand, NaVO3 microcrystals and particles constituted -NaVO3 and -NaVO3 were formed at acidic pH, whereas Na metavanadate nanoparticles were formed at pH=9.0. These nanoparticles transformed into an -NaVO3 type phase upon dehydration. The reducibility of the catalysts was a function of the impregnation pH, where the catalysts synthesized at pH=3.8 and 9.0 displayed similar reduction patterns but lower reducibility than those synthesized at pH=1.5. The produced patterns were correlated to the existence of a mixture of V5+ and V4+ species among which V4+ was prevalent for the catalysts synthesized at pH=3.8 and 9.0. Consequently, the basicity of the catalysts decreased with the increase in pH. The surface concentration of vanadium increased with the increase in the concentration of vanadium in solution, while the pH had a weak negative effect over the former. On the other hand, it was established that chemical surface state of oxygen in the synthesized catalysts was influenced weakly by the synthesis pH and, more importantly, by non-additive effects between the pH and the concentration of vanadium in solution. The latter was coherent with the detection of surface oxygen species related to the partial dissolution of the Na-SiO2 support; a phenomenon that seemed to be favored at acidic pH. The latter properties were correlated to changes in basicity. Concerning the catalytic performance, the catalysts synthesized at pH=9.0 displayed the best steady state performance in terms of the selectivity to propene and oxygen consumption. The collected evidence allowed corroborating that both the oxidative dehydrogenation of propane to propene and its combustion to CO and CO2 are kinetically controlled by the initial activation of one of the C-H bonds of propane. But, the production of CO2 depended on the level of consumption of O2; where, a surplus of the latter compared to the conversion of propane combusted the hydrocarbon into CO2. Such a finding agreed with what has already been established for supported vanadium oxides for hydrocarbon oxidation. An analysis of the Raman spectra of the spent catalysts suggested that under the applied reaction conditions, all catalysts were provided of an active phase mostly constituted by -NaVO3 type structures. Therefore, the observed differences in catalytic behavior were rather associated to changes in particle size, reducibility, and acidity

Genetics, Morphometrics and Health Characterization of Green Turtle Foraging Grounds in Mainland and Insular Chile

Two divergent genetic lineages have been described for the endangered green turtle in the Pacific Ocean, occurring sympatrically in some foraging grounds. Chile has seven known green turtle foraging grounds, hosting mainly juveniles of different lineages. Unfortunately, anthropic factors have led to the decline or disappearance of most foraging aggregations. We investigated age-class/sex structure, morphological variation, genetic diversity and structure, and health status of turtles from two mainland (Bahia Salado and Playa Chinchorro) and one insular (Easter Island) Chilean foraging grounds. Bahia Salado is composed of juveniles, and with Playa Chinchorro, exclusively harbors individuals of the north-central/eastern Pacific lineage, with Galapagos as the major genetic contributor. Conversely, Easter Island hosts juveniles and adults from both the eastern Pacific and French Polynesia. Morphological variation was found between lineages and foraging grounds, suggesting an underlying genetic component but also an environmental influence. Turtles from Easter Island, unlike Bahia Salado, exhibited injuries/alterations probably related to anthropic threats. Our findings point to establishing legal protection for mainland Chile’s foraging grounds, and to ensure that the administrative plan for Easter Island’s marine protected area maintains ecosystem health, turtle population viability, and related cultural and touristic activities

Comparación de dos métodos isotérmicos para la detección de SARS-COV-2 en Callao, Perú

Objetivo: Comparar las técnicas de cribado molecular isotérmico CPA y RT-LAMP, frente a la prueba de referencia, la reacción en cadena de la polimerasa cuantitativa de transcripción inversa (RT-qPCR), y determinar su concordancia. Materiales y métodos: Estudio comparativo de casos y controles emparejados. Para la evaluación del método CPA se utilizaron 70 casos y 130 controles, mientras que para la RT-LAMP se utilizaron 30 casos y 70 controles. Se calcularon la sensibilidad y la especificidad de ambas pruebas. Posteriormente, se calculó el índice Kappa corregido por sesgo mediante un nuevo muestreo. Resultados: Ambas técnicas presentan valores adecuados y equivalentes de sensibilidad (RT-LAMP: 82,8 %, CPA: 83 %) y especificidad (RT-LAMP y CPA: 91,5 %), así como una alta concordancia (88 %), y un índice Kappa (0,72). Conclusiones: Ambas técnicas de cribado molecular isotérmico son adecuadas para el cribado del SARS-CoV-2, con una sensibilidad y especificidad similares

Shifting the mindset culture to address global educational disparities

Abstract Educational outcomes remain highly unequal within and across nations. Students’ mindsets—their beliefs about whether intellectual abilities can be developed—have been identified as a potential lever for making adolescents’ academic outcomes more equitable. Recent research, however, suggests that intervention programs aimed at changing students’ mindsets should be supplemented by programs aimed at the changing the mindset culture, which is defined as the shared set of beliefs about learning in a school or classroom. This paper reviews the theoretical and empirical origin of the mindset culture and examines its potential to reduce group-based inequalities in education. In particular, experiments have identified two broad ways the mindset culture is communicated by teachers: via informal messages about growth (e.g., that all students will be helped to learn and succeed), and formal opportunities to improve (e.g., learning-focused grading policies and opportunities to revise and earn credit). New field experiments, applying techniques from behavioral science, have also revealed effective ways to influence teachers’ culture-creating behaviors. This paper describes recent breakthroughs in the U.S. educational context and discusses how lessons from these studies might be applied in future, global collaborations with researchers and practitioners