Frailty in severe COVID-19 survivors after ICU admission. A prospective and multicenter study in Mexico.

OBJECTIVE: To analyze the presence of frailty in survivors of severe COVID-19 admitted in the Intensive Care Unit (ICU) and followed six months after discharge. DESIGN: An observational, prospective and multicenter, nation-wide study. SETTING: Eight adult ICU across eight academic acute care hospitals in Mexico. PATIENTS: All consecutive adult COVID-19 patients admitted in the ICU with acute respiratory failure between March 8, 2020 to February 28, 2021 were included. Frailty was defined according to the FRAIL scale, and was obtained at ICU admission and 6-month after hospital discharge. INTERVENTIONS: None. MAIN VARIABLES OF INTEREST: The primary endpoint was the frailty status 6-months after discharge. A regression model was used to evaluate the predictors during ICU stay associated with frailty. RESULTS: 196 ICU survivors were evaluated for basal frailty at ICU admission and were included in this analysis. After 6-months from discharge, 164 patients were evaluated for frailty: 40 patients (20.4%) were classified as non-frail, 67 patients (34.2%) as pre-frail and 57 patients (29.1%) as frail. After adjustment, the need of invasive mechanical ventilation was the only factor independently associated with frailty at 6 month follow-up (Odds Ratio [OR] 3.70, 95% confidence interval 1.40-9.81, P = .008). CONCLUSIONS: Deterioration of frailty was reported frequently among ICU survivors with severe COVID-19 at 6-months. The need of invasive mechanical ventilation in ICU survivors was the only predictor independently associated with frailty.

Self-grafting-induced epigenetic changes leading to drought stress tolerance in tomato plants.

Grafting is widely used as a method to increase stress tolerance in good fruiting lines of Solanaceae plants. However, little is known about how grafting, affects epigenetic modifications and leads to stress tolerance, especially within the same line. Here, we studied the effects of self-grafting in tomato plants on histone and DNA modifications and changes in gene expression related to drought stress. We found that at the three-leaf stage, 1 week after self-grafting, histone H3 K4 trimethylation and K27 trimethylation changes were observed in more than 500 genes each, and DNA methylation changes in more than 5,000 gene regions at the shoot apex compared to the non-grafted control. In addition, two weeks after the epigenomic changes, global expression changes continued to be observed at the shoot apex in several genes related to the metabolic process of nitrogen compounds, responses to stimulus, chromosome organization, cell cycle-related genes, and regulation of hormone levels. Finally, these grafted seedlings acquired remarkable drought tolerance, suggesting that epigenomic modifications during the wound-healing process mitigate stress tolerance in tomato plants.

Comparative Transcriptome Analysis of Grafted Tomato with Drought Tolerance.

Grafting is a method used in agriculture to improve crop production and tolerance to biotic and abiotic stress. This technique is widely used in tomato, Solanum lycopersicum L.; however, the effects of grafting on changes in gene expression associated with stress tolerance in shoot apical meristem cells are still under-discovered. To clarify the effect of grafting, we performed a transcriptomic analysis between non-grafted and grafted tomatoes using the tomato variety Momotaro-scion and rootstock varieties, TD1, GS, and GF. Drought tolerance was significantly improved not only by a combination of compatible resistant rootstock TD1 but also by self-grafted compared to non-grafted lines. Next, we found the differences in gene expression between grafted and non-grafted plants before and during drought stress treatment. These altered genes are involved in the regulation of plant hormones, stress response, and cell proliferation. Furthermore, when comparing compatible (Momo/TD1 and Momo/Momo) and incompatible (Momo/GF) grafted lines, the incompatible line reduced gene expression associated with phytohormones but increased in wounding and starvation stress-response genes. These results conclude that grafting generates drought stress tolerance through several gene expression changes in the apical meristem.

Encuesta entomológica y caracterización de las viviendas con el vector de la enfermedad de Chagas, en aldea Chuchuapa, Santa Rosa, Guatemala / Entomological survey and characterization of houses with the vector of Chagas disease, in Chuchuapa village, Santa Rosa, Guatemala

En Guatemala en el 2015, el Ministerio de Salud Pública y Asistencia Social (MSPAS) reportó nuevos casos de la enfermedad de Chagas en la región suroriental del país, siendo Santa Rosa uno de los departamentos endémicos en donde Triatoma dimidiata es el principal transmisor. Se estimó la infestación de T. dimidiata en la aldea Chuchuapa, municipio de Santa María Ixhuatán, de abril a junio de 2019, se calcularon los índices en-tomológicos y se caracterizaron intra y peridomiciliar 149 viviendas (79.67% de las viviendas habitadas). Los datos se obtuvieron mediante un cuestionario mixto, en entrevista cara a cara y evaluación de las viviendas, por un equipo profesional experimentado, mediante el método y protocolo estándar hombre-hora. Se capturaron 20 triatominos en 10 viviendas, con un índice de infestación de 6.71% (10/149), un índice de densidad de 13.42% (20/149), 19 triatominos intradomiciliares y uno peridomiciliar, con un índice de infección natural por Tr y pano-soma cruzi intradomiciliar de 26.3% (5/19), índice de infección natural por T. cr u z i peridomiciliar de 100.0% (1/1) e índice de infección natural por T. c r u z i en los triatominos capturados de 30.0 % (6/20). Las viviendas infestadas presentaron techo de lámina, pared de bajareque con grietas y sin repello, piso de tierra y afiches en la pared, acumulación de leña u otros materiales tanto intra como peridomiciliar, convivencia con animales domésticos y tenencia de animales de corral. Los resultados representan un alto riesgo para la transmisión de la enfermedad de Chagas entre los habitantes de la aldea.

In Guatemala in 2015, the Ministry of Public Health and Social Assistance reported new cases of Chagas disease in the southeastern region of the country, with Santa Rosa being one of the endemic departments where Tr ia-toma dimidiata is the main transmitter. The infestation of T. dimidiata was estimated in the Chuchuapa village, municipality of Santa María Ixhuatán, from April to June 2019, the entomological indices were calculated and 149 dwellings were characterized intradomiciliary and peridomiciliary (79.67% of the inhabited dwellings). The data were obtained through a mixed questionnaire, in a face-to-face interview and evaluation of the dwellings, by an experienced professional team, using the standard man-hour method and protocol. 20 triatomines were captured in 10 homes, with an infestation index of 6.71% (10/149), a density index of 13.42% (20/149), 19 intradomiciliary triatomines and one peridomiciliary, with a natural infection index by intradomiciliary Trypanosomacruzi of 26.3% (5/19), natural infection index by peridomiciliary T. c r u z i of 100.0% (1/1) and natural infection index by T. c r u z i in captured triatomines of 30.0% (6/20). The infested dwellings have a sheet roof, awattle and daub wall with cracks and no wall plaster, dirt and posters on the wall, accumulation of firewood and other materials in both intradomiciliary and peridomiciliary, living with domestic animals and keeping poultry animals. The results represent a high risk for the transmission of Chagas disease among the villager.

El alimento como sincronizador de los ritmos biológicos: su relevancia para la identificación de un oscilador circadiano / Feeding as a biorhytm synchronizer

Aparte de las variaciones cíclicas tales como día-noche, estaciones y cambios de temperatura y humedad, los organismos vivos han desarrollado adaptaciones para ajustar su fisiología y su conducta a otros cambios exteriores y para ello aparecieron en la evolución los relojes biológicos, cuyo prototipo -y hasta ahora el único bien caracterizado-, es el ubicado en el núcleo supra-quiasmático del hipotálamo, que percibe señales aferentes de la retina e informa al resto del sistema nervioso central.Hay otros marcapasos locales identificados in vitro en el pulmón y el hígado, que muestran oscilaciones circadianas y se acepta que actúan como sincronizadores de otros ritmos biológicos del organismo.Los autores demuestran, en experimentos en ratas, que la llegada del alimento actúa como sincronizador, al restringir el mismo o cambiar la alternancia de su administración. Esto afecta los procesos de balance energético, los estados de anabolismo o catabolismo, reflejados en los niveles de ácidos grasos y cuerpos cetónicos en sangre, la glucosa, la insulina y la leptina. Es más, parece que el hígado contiene un sistema de estimación del tiempo que lo convierte en un oscilador circadiano.