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2.
JACS Au ; 4(7): 2630-2639, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39055146

RESUMEN

The development of transition metal-based catalytic platforms that promote bioorthogonal reactions inside living cells remains a major challenge in chemical biology. This is particularly true for palladium-based catalysts, which are very powerful in organic synthesis but perform poorly in the cellular environment, mainly due to their rapid deactivation. We now demonstrate that grafting Pd(II) complexes into engineered ß-sheets of a model WW domain results in cell-compatible palladominiproteins that effectively catalyze depropargylation reactions inside HeLa cells. The concave shape of the WW domain ß-sheet proved particularly suitable for accommodating the metal center and protecting it from rapid deactivation in the cellular environment. A thorough NMR and computational study confirmed the formation of the metal-stapled peptides and allowed us to propose a three-dimensional structure for this novel metalloprotein motif.

3.
Sci Total Environ ; 666: 662-671, 2019 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-30812000

RESUMEN

Large quantities of contaminants of emerging concern (CECs) are susceptible of entering the terrestrial environments through the application of recycled wastewater, manures, and biosolids, resulting in their progressive contamination and possible long-term effects over terrestrial species. Many studies on the environmental fate of CECs focus on aquatic environments and/or wastewater treatment plants, but little is still known about their behavior at environmentally relevant concentrations in agricultural soils. In this study, we evaluated the adsorption and degradation of nine different pharmaceuticals (nadolol, sulfamethizole, sulfamethoxazole, sulfamethopyridazone, carbamazepine, ibuprofen, diclofenac, hydrochlorothiazide, and gemfibrozil) and four artificial sweeteners (acesulfame, saccharin, cyclamate, and sucralose) in two soils under aerobic and anaerobic conditions. The sorption of target compounds in soils fitted well to a Freundlich isotherm model and was relatively low (Kf < 200 L kg-1). Sorption was highest for cyclamate (Kf = 162 L kg-1) and acesulfame (Kf = 156 L kg-1), while lowest sorption coefficients were measured for ibuprofen (Kf = 1-7 L kg-1). All target compounds (except for carbamazepine) were susceptible to microbial degradation under aerobic conditions, with half-lives ranging from 1 to 18 days. Degradation occurred at a higher rate under aerobic conditions for most contaminants, but they were relatively persistent under anaerobic conditions. For instance, over 90% of the initial amount of spiked nadolol was degraded in aerobic soils after 4 days of incubation, while only 18-24% was lost in absence of oxygen after 1 month, resulting in t1/2 values between 95 and 103 days. The degradation behavior of the target compounds varied in relation to soil and compound physicochemical properties as well as the microbial activities (e.g., 220 ppm of CH4 were produced in anaerobic experiments) and aeration of the tested soils. Overall, the poor adsorption and relative persistence of sucralose and carbamazepine suggests that both may be used as potential tracers for soil and groundwater contamination.


Asunto(s)
Monitoreo del Ambiente , Preparaciones Farmacéuticas/análisis , Contaminantes del Suelo/análisis , Edulcorantes/análisis , Adsorción , Aerobiosis , Riego Agrícola , Anaerobiosis , Biodegradación Ambiental , Contaminantes del Suelo/metabolismo , Aguas Residuales/análisis
4.
Nutr Hosp ; 32(2): 582-9, 2015 Aug 01.
Artículo en Español | MEDLINE | ID: mdl-26268085

RESUMEN

INTRODUCTION: Food-Based Dietary Guidelines (FBDG) are usually accompanied by an image for dissemination and implementation. OBJECTIVE: to design and validate an image to represent the variety and proportions of the new Chilean dietary guidelines, include foods high in critical nutrients that should be avoided and physical activity guidelines. METHOD: a panel of experts tested seven graphics and selected three that were validated with 12 focus groups of people aged 10-14 and 20-40 years, of both sexes, from different socioeconomic groups and from both rural and urban areas. We analyzed the perception of variety and proportions of the food groups for daily intake and motivation for action in diet and physical activity. We utilized the METAPLAN method used previously in the validation of FBDG. RESULTS AND DISCUSSION: the final image was a circle that showed the variety and proportions of each food group for daily consumption (in pictures), included physical activity guidelines in a strip around the middle of the circle and a rectangle towards of bottom of the image with examples of foods high in critical nutrients in black and white. The chosen picture was modified using input from participants and validated with three additional focus groups, improving its understanding and acceptance. CONCLUSION: most participants understood that the image represented the relationship between healthy eating and daily physical activity, correctly identifying the food groups for which increased intake was suggested and those groups in which intake should be reduced or avoided.


Introducción: las Guías Alimentarias Basadas en Alimentos (GABA) generalmente van acompañadas de una imagen para su difusión e implementación. Objetivo: diseñar y validar una imagen que represente la variedad y proporcionalidad de las nuevas guías alimentarias para la población chilena, incluyendo los alimentos altos en nutrientes críticos que es necesario evitar y la actividad física. Método: un panel de expertos analizó siete propuestas gráficas y seleccionó tres que fueron validadas con 12 grupos focales de personas de 10-14 y 20-40 años, distinto sexo, nivel socioeconómico y sector urbano/rural. Se analizó la percepción de la variedad y proporcionalidad de los grupos de alimentos a comer diariamente y la motivación a la acción en alimentación y actividad física. Se trabajó con METAPLÁN, método ya utilizado en la validación de las GABA. Resultados y discusión: la imagen definitiva es un círculo que presenta la variedad y proporcionalidad de los grupos de alimentos a consumir durante el día (en fotografías), incluye la actividad física en una franja que rodea la mitad del círculo y un rectángulo inferior con ejemplos de alimentos altos en nutrientes críticos en blanco y negro. La imagen elegida fue modificada con las aportaciones de los participantes y validada con tres nuevos grupos focales, mejorando su comprensión y aceptación. Conclusión: la mayoría de los participantes comprendió que la imagen representaba la relación entre la alimentación saludable y la actividad física diaria, identificando los grupos de alimentos de los que se sugiere comer más y de los que se necesita reducir o evitar su consumo.


Asunto(s)
Promoción de la Salud/métodos , Política Nutricional , Adolescente , Adulto , Niño , Femenino , Grupos Focales , Análisis de los Alimentos , Humanos , Masculino , Valor Nutritivo , Adulto Joven
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