Producción de la enzima lignina peroxidasa H8 en la levadura metilotrófica Pichia pastoris

La producción de enzimas del complejo degradador de la madera es importante para un amplio rango de actividades industriales, tal es el caso de la lignina peroxidasa que es usada en el pretratamiento del material lignocelulósico en procesos de biorefinado y la degradación de compuestos tóxicos como colorantes, hidrocarburos aromáticos policíclicos (HAPs), nanomateriales y antibióticos mediante estrategias de biorremediación. Adicionalmente se le han atribuido funciones de producto con alto valor agregado como agente despigmentante, biosensor o en la generación de aditivos alimenticios (ácido ferúlico y vainillina) y biocombustibles basados en la conversión de lignina. Lo anterior hace que su producción recombinante sea de interés biotecnológico. Los esfuerzos previos de clonación han generado resultados desalentadores siendo los más comunes: bajo rendimiento, baja actividad y la necesidad de procesos adicionales para favorecer el correcto plegamiento. En el presente trabajo se exploró una alternativa para solventar estos inconvenientes mediante la producción heteróloga de la enzima lignina peroxidasa H8 en la levadura metilotrófica Pichia pastoris, además se implementó una estrategia de optimización de codones basada en emular el perfil de uso de codones presente en el organismo nativo en la secuencia de interés a insertar en el organismo hospedero. Objetivo: Expresar y caracterizar la isoforma H8 de la enzima lignina peroxidasa en la cepa GS115 de Pichia pastoris. Metodología. Se diseñó una secuencia con armonización de codones de la isoforma del gen LiPH8 de la lignina peroxidasa de Phanerochaete chrysosoporium y se envió a sintetizar artificialmente en el vector de expresión para levaduras pPIC9K

Pollen collection and honey bee forager distribution in cantaloupe

Honey bee (Apis mellifera, L.) pollen collection and forager distribution were examined during the 2002 summer in a cantaloupe (Cucumis melo, L., Cruiser cv ) field with plastic mulch and drip irrigated. The experimental site was located near the INIFAP Campo Experimental La Laguna, Matamoros, Coahuila within La Laguna region, Mexico. Two trials were conducted in the same location, but were separated by a 800 m wide pecan orchard. Both cantaloupe trials were planted the same date. Trial 1. Nine honey-bee hives were placed in a three hectare field at the start of bloom. Each hive was fitted with a modified-Ontario pollen trap. The pollen was collected one day a week from each colony every hour beginning from 8:30 hr to 14:30 hr during the first four blooming weeks of the crop. Trial 2. Three weeks after the start of bloom, in a ten-ha field 30 honey bee colonies were located. In four randomlyselected rows of 105 m long, 10 m transects at 25, 50, 75 and 100 m distances from the apiary were marked. The foraging bees were counted simultaneously at the transects every half hour from 7:30 hr until 20:30 hr at the same pollen collection-day during the third week of cantaloupe bloom. Pollen collection was higher early in the morning (22.6 g per colony), dropping to medium amount from 9:30 hr (13.7 g), 10:30 hr (12.5 g) to 11:30 hr (9.5 g) and remaining low from 12:30 through the afternoon (less than 2.6 g per colony; p< 0.05). The distribution pattern showed that bees were in the cantaloupe after 8:00 hr, reaching a maximum between 10:30 hr and 14:30 hr when the bees began to decrease, until foraging flights ceased completely at about 20:30 hr. No statistical differences were found in the number of foraging bees among the evaluated distances from the apiary.Durante el verano del 2002 la colecta de polen y la distribución de las abejas (Apis mellifera L.) pecoreadoras fueron estudiadas en el cultivo de melón (Cucumis melo L., cv Cruiser ) bajo condiciones de riego por goteo y acolchado plástico. El lote experimental estuvo localizado cerca del Campo Experimental La Laguna del INIFAP, en el municipio de Matamoros, Coahuila, México. Dos experimentos se realizaron en el mismo predio, en lotes separados 800 m por una huerta de nogal. Ambas superficies de melón fueron sembradas en la misma fecha. Experimento N° 1. Al inicio de la floración se colocaron nueve colmenas en tres hectáreas de cultivo. Cada colmena contó con una trampa de polen tipo Ontario modificada. El polen se colectó cada hora de cada colmena un día por semana de las 8:30 hr a las 14:30 hr durante las cuatro primeras semanas de floración del cultivo. Experimento N° 2. Tres semanas después del inicio de la floración se colocaron 30 colmenas en un campo de melón de diez hectáreas. En cuatro surcos de 105 m de longitud se marcaron transectos de diez metros a 25, 50, 75 y 100 metros de distancia del apiario. Las abejas pecoreadoras fueron contadas simultáneamente en cada transecto cada media hora de las 7:30 hr hasta las 20:30 horas, el mismo día en que fue colectado el polen de la tercera semana de floración. La colecta de polen fue mayor temprano por la mañana (22.6 g por colmena), disminuyendo a una cantidad media de las 9:30 hr (13.7 g), 10:30 hr (12.5 g) a las 11:30 hr (9.5 g) y permaneciendo baja desde las 12:30 hasta el mediodía (menos de 2.6 g por colmena; p<0.05). El patrón de distribución mostró que las abejas se presentaron en el cultivo de melón después de las 8:00 hr y alcanzaron su máximo entre las 10:30 hr y las 14:30 hr cuando las abejas iniciaron su disminución hasta el cese de los vuelos a las 20:30 hr. No se encontraron diferencias significativas en el número de abejas pecoreadoras a las diferentes distancias del apiario que fueron evaluadas

Maternal dietary patterns and acute leukemia in infants: results from a case control study in Mexico

BackgroundChildhood cancer is the leading cause of disease-related mortality among children aged 5–14 years in Mexico, with acute leukemia being the most common cancer among infants. Examining the overall dietary patterns allows for a comprehensive assessment of food and nutrient consumption, providing a more predictive measure of disease risk than individual foods or nutrients. This study aims to evaluate the association between maternal dietary patterns during pregnancy and the risk of acute leukemia in Mexican infants.MethodsA hospital-based case–control study was conducted, comparing 109 confirmed acute leukemia cases with 152 age-matched controls. All participants (≤24 months) were identified at hospitals in Mexico City between 2010 and 2019. Data on a posteriori dietary patterns and other relevant variables were collected through structured interviews and dietary questionnaires. Multivariate logistic regression was employed to estimate the association between maternal dietary patterns during pregnancy and the risk of acute leukemia in infants.ResultsThe “Balanced & Vegetable-Rich” pattern, characterized by a balanced consumption of various food groups and higher vegetable intake, exhibited a negative association with acute leukemia when compared to the “High Dairy & Cereals” Pattern (adjusted odds ratio [OR] = 0.51; 95% confidence interval [CI]: 0.29, 0.90). We observed that mothers who gave birth to girls and adhered to a healthy dietary pattern during pregnancy exhibited significantly lower odds of their children developing AL compared to those who gave birth to boys [OR = 0.32 (95% CI 0.11, 0.97)]. Our results underscore the significance of maternal nutrition as a modifiable factor in disease prevention and the importance of prenatal health education

Approaching Optimal Nonlinear Dimensionality Reduction by a Spiking Neural Network

This work deals with the presentation of a spiking neural network as a means for efficiently solving the reduction of dimensionality of data in a nonlinear manner. The underneath neural model, which can be integrated as neuromorphic hardware, becomes suitable for intelligent processing in edge computing within Internet of Things systems. In this sense, to achieve a meaningful performance with a low complexity one-layer spiking neural network, the training phase uses the metaheuristic Artificial Bee Colony algorithm with an objective function from the principals in the machine learning science, namely, the modified Stochastic Neighbor Embedding algorithm. To demonstrate this fact, complex benchmark data were used and the results were compared with those generated by a reference network with continuous-sigmoid neurons. The goal of this work is to demonstrate via numerical experiments another method for training spiking neural networks, where the used optimizer comes from metaheuristics. Therefore, the key issue is defining the objective function, which can relate optimally the information at both sides of the spiking neural network. Certainly, machine learning techniques have advanced in defining efficient loss functions that can become suitable objective function candidates in the metaheuristic training phase. The practicality of these ideas is shown in this article. We use MSE values for evaluating the relative quality of the results and also co-ranking matrices

Programa de muestreo para el pulgón amarillo del sorgo, Melanaphis sacchari (Zehntner)

Abstract. This study was conducted with the aim of developing a sampling program for the sugarcane aphid (Melanaphis sacchari Zehntner). This pest is currently the most economically important in sorghum cultivation in Mexico and other countries. Five samplings of the pest were made in 10 sorghum farms in the Comarca Lagunera. The variance (S2)-media (m)ratio for the number of aphids was determined using the Taylor Power Law model and the optimal sample sizes were estimated. Maximum densities varied from 394.7 to 754.1 aphids per leaf in July. Through the regression model obtained [log (S2) = 0.4374 + 1.6513 log (m), r2 = 0.98], it was determined that for the sampling of the sugarcane aphid in sorghum, at least 39 leaves must be inspected per farm, with an accuracy of 80%.Resumen. El presente estudio se realizó con el objetivo de desarrollar un programa de muestreo para el pulgón amarillo del sorgo (Melanaphis sacchari Zehntner). Esta plaga es actualmente la de mayor importancia económica en el cultivo de sorgo en México y otros países. Se efectuaron cinco muestreos de la plaga en 10 predios de sorgo de la Comarca Lagunera. Se determinó la relación varianza (S2)-media (m) para el número de pulgones mediante el modelo de la Ley de Poder de Taylor y se estimaron los tamaños de muestra óptimos. Las densidades máximas variaron de 394.7 a 754.1 pulgones por hoja en el mes de julio. A través del modelo de regresión obtenido [log (S2) = 0.4374 + 1.6513 log (m), r2 = 0.98] se determinó que para el muestreo del pulgón amarillo del sorgo se deben inspeccionar al menos 39 hojas por predio, con una precisión del 80%

Stress factors and food purchase prioritization during the pandemic of coronavirus disease 2019

Background: The pandemic of coronavirus disease 2019 (COVID-19) pandemic confinement has an impact on stress levels, which causes changes in food purchase and consumption behaviors. The objective of this study is to associate food purchase prioritization with stress level during the COVID-19 pandemic confinement. Methods: Multicenter, observational and cross-sectional study, an online questionnaire that included data on sociodemographic variables, stress factors and food purchase prioritization was disseminated through digital platforms and social networks. Results: A number of 6357 participants were included, of whom 83.6% were female, 56.3% were from the middle socioeconomic level, 71.2% had completed higher education and 78.3% had a job. At greater stress levels it was observed a higher prioritization of canned foods (Odds ratio (OR): 1.91, 95% CI: 1.56; 2.34), sweets (OR: 1.58, 95% CI: 1.06; 2.34) and flours (OR: 1.45, 95% CI: 1.25; 1.68). While lower stress levels are associated with nuts (OR: 0.75, 95% CI: 0.66; 0.85), vegetables (OR: 0.82, 95% CI: 0.72; 0.94), and fruits (OR: 0.90, 95% CI: 0.80; 1.01), after adjusting for confounders. Conclusions: There is an association between food purchase prioritization and stress level during the COVID-19 confinement. At greater stress levels, individuals purchase more food, both healthy and unhealthy. The later may have a negative impact on people's health, leading to or further aggravating malnutrition by excess and nutrition-related noncommunicable diseases

Can topical epinephrine application to the papilla prevent pancreatitis after endoscopic retrograde cholangiopancreatography? Results from a double blind, multicentre, placebo controlled, randomised clinical trial

Background and study aims Post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) is a complication associated with important morbidity, occasional mortality and high costs. Preventive strategies are suboptimal as PEP continues to affect 4% to 9% of patients. Spraying epinephrine on the papilla may decrease oedema and prevent PEP. This study aimed to compare rectal indomethacin plus epinephrine (EI) versus rectal indomethacin plus sterile water (WI) for the prevention of PEP.Patients and methods This multicentre randomised controlled trial included patients aged >18 years with an indication for ERCP and naive major papilla. All patients received 100 mg of rectal indomethacin and 10 mL of sterile water or a 1:10 000 epinephrine dilution. Patients were asked about PEP symptoms via telephone 24 hours and 7 days after the procedure. The trial was stopped half way through after a new publication reported an increased incidence of PEP among patients receiving epinephrine.Results Of the 3602 patients deemed eligible, 3054 were excluded after screening. The remaining 548 patients were randomised to EI group (n=275) or WI group (n=273). The EI and WI groups had similar baseline characteristics. Patients in the EI group had a similar incidence of PEP to those in the WI group (3.6% (10/275) vs 5.12% (14/273), p=0.41). Pancreatic duct guidewire insertion was identified as a risk factor for PEP (OR 4.38, 95% CI (1.44 to 13.29), p=0.009).Conclusion Spraying epinephrine on the papilla was no more effective than rectal indomethacin alone for the prevention of PEP.Trial registration number This study was registered with ClinicalTrials.gov (NCT02959112)

Reporte Final PAP Primavera 2020: Playas región costa sur, Mezcala y UMAS, gestión integral de residuos del Estado de Jalisco, incorrecta disposición de los residuos líquidos denominados vinazas,CONAFOR y SEMADET

El proyecto de aplicación personal sobre el cual versa el presente reporte tiene con objetivo ser un vínculo de observancia de procuración de justicia ambiental, de tal forma, que, mediante este, se busca que los alumnos se conviertan en actores activos de las problemáticas ambientales que se gestan tanto en el nivel local, estatal y nacional. Para lograr esto, el equipo de alumnos se conforma por estudiantes de diversas carreras universitarias con la finalidad de generar un dialogo interseccional que permita generar el conocimiento y los insumos suficientes para generar estrategias y soluciones a problemas complejos, siempre buscando tener como eje rector la justicia ambiental. Para lograr el propósito de que los alumnos conozcan, desarrollen y propongan soluciones es que se genera un proceso de colaboración con una diversidad de actores relacionados dentro de la sociedad, de esta forma, buscando que el análisis crítico de la problemática ambiental que aborda al estado de Jalisco y las posibles soluciones para el apoyo de dichos grupos vulnerables. Este proyecto de aplicación profesional busca adentrar a los alumnos desde tres perspectivas distintas como lo son la academia, el sector privado y la administración pública buscando con esto dar a conocer el contexto de la complejidad del Derecho Ambiental a través de su aplicación desde una visión de procuración de justicia y la justiciabilidad. Dando como resultado una experiencia en donde el contacto con distintos sectores de la población, la aplicación de los conocimientos adquiridos durante la carrera y el análisis crítico de la realidad de los conflictos ambientales desde una perspectiva Ignaciana den como resultado la ejecución de mecanismos de procuración de justicia sobre la problemática ambiental que vive nuestro estado.ITESO, A.C