Evaluación del efecto antidiabético In vitro e in vivo de los extractos de las semillas y penca de Opuntia engelmanii y Cylindropuntia imbricata, semillas de Theobroma cacao y la raíz de Ibervillea sonorae.

La diabetes es la tercera causa de muerte a nivel mundial, afectando a más de 382 millones de personas en el mundo y la tendencia es que siga en aumento. Las complicaciones relacionadas con la diabetes pueden conducir a la insuficiencia de órganos vitales y finalmente a la muerte; disminuyendo considerablemente la calidad de vida de quien la padece. Para contrarrestarla, se han producido un gran número de medicamentos sintéticos, sin embargo estos presentan efectos secundarios indeseados, por lo que el uso de hierbas medicinales con actividad antidiabética ha aumentado. Por lo anterior, en esta investigación se pretende evaluar cuatro especies de plantas comunes en México, a fin de identificar si presentan actividad antidiabética. Para ello, se evaluó la toxicidad en células B16F10, las capacidades anti-oxidante y antihiperglicemiante, mediante pruebas realizadas in vitro de los extractos obtenidos por maceración continua en orden creciente de polaridad, además de evaluar sus principales constituyentes químicos y seleccionar los extractos con los mejores resultados para evaluar mediante pruebas in vivo su capacidad antihiperglicemiante y el efecto hipoglucemiante a corto y a largo plazo con ratones diabéticos inducidos por estreptozocina. Los resultados obtenidos fueron que los extractos polares de las semillas de C. imbricata, T. cacao y O. engelmannii no mostraron toxicidad en las pruebas realizadas. Además, estos extractos mostraron tener una acción dual antidiabética al ser agentes antihiperglucemiantes, así como hipoglucemiantes. Por lo que se recomienda continuar con la investigación de estos como candidatos en el tratamiento y/o coadyuvantes en el control de la diabetes mellitus. ABSTRACT Diabetes is the third leading cause of death worldwide, affecting more than 382 million people across the world, and the trend is that it continues increasing. Diabetes-related complications can lead to insufficient vital organs and eventually to death; considerably reducing the quality of life of those who suffer. To counteract it, a large number of synthetic drugs exist, however they have unwanted side effects, so the use of medicinal herbs with antidiabetic activity has increased. Therefore, this research intends to evaluate four species of plants common in Mexico, in order to identify at least one extract that has an effective antidiabetic response. For this purpose, toxicity in B16F10 cells, anti-oxidant and antihyperglycaemic capacities were evaluated by in vitro tests of the extracts obtained by continuous maceration in increasing order of polarity, as well as evaluating their main chemical constituents and selecting the extracts with the better results to evaluate in vivo tests their antihyperglycemic capacity and the short-term and long-term hypoglycemic effect with diabetic mice induced by streptozocin. As result it was obtained that the extracts of the seeds of C. imbricata, T. cacao and O. engelmannii showed no toxicity in the tests performed. In addition, these extracts were shown to have a dual antidiabetic action as antihyperglycemic agents, as well as hypoglycemic agents. Therefore, they are suitable candidates to be used in the development of treatments against diabetes

Diagnostic criteria in proliferative verrucous leukoplakia: evaluation

Objectives: to evaluate the ability of the diagnostic criteria proposed by Cerero et al in 2010 to perform an early diagnose in patients with proliferative verrucous leukoplakia. Study Design: retrospective study with patients diagnosed with leukoplakia at Oral Medicine Service at Oral Medicine and Surgery Department at Dentistry Faculty at Universidad Complutense of Madrid. Results: the criteria were applied in 116 patients, turning positive in 40 cases. Out of these, 24 (60%) had been previously diagnosed with PVL. Most frequent criteria were major criteria A and E, concerning lesion's site and histopathology, and minor criteria b and c, concerning sex and smoking habit. Conclusions: diagnostic criteria developed by Cerero et al can be a useful tool for an early diagnose of PVL, as in 60% of the cases, the criteria would have allowed to make an early diagnose of the disease

Safety verification of asynchronous pushdown systems with shaped stacks

In this paper, we study the program-point reachability problem of concurrent pushdown systems that communicate via unbounded and unordered message buffers. Our goal is to relax the common restriction that messages can only be retrieved by a pushdown process when its stack is empty. We use the notion of partially commutative context-free grammars to describe a new class of asynchronously communicating pushdown systems with a mild shape constraint on the stacks for which the program-point coverability problem remains decidable. Stacks that fit the shape constraint may reach arbitrary heights; further a process may execute any communication action (be it process creation, message send or retrieval) whether or not its stack is empty. This class extends previous computational models studied in the context of asynchronous programs, and enables the safety verification of a large class of message passing programs

Light-induced effects on crystal size and photo-stability of colloidal CsPbBr3 perovskite nanocrystals

CsPbBr3 perovskite nanocrystals (PNCs) have been synthesized using the hot injection method. The CsPbBr3 PNCs exhibit a high photoluminescence quantum yield (PLQY) of 73%. A comprehensive study of UV light interaction with the CsPbBr3 PNCs was performed. SEM images, photolumines- cence spectra, x-ray Diffraction and PLQY measurements were obtained for different time of UV exposure. The exposure to UV light modifies the crystal size (from 10 ×10 nm to 12 × 95 nm) and morphology (change from nanocubic to nanorods form). The XRD spectra show a change from tetragonal to cubic crystalline structure. In addition, the interaction of UV light modifies the optical properties of the PNCs by varying the photoluminescence. The material remains stable for a period of 1 h, however, with exposure to UV light, the PNCs show a decrement in QY from 73.3% to 46.6% after 30 days. These results indicate that light-induce variation in morphological and photo-stability of CsPbBr3 PNCs

Optimal Strategies in Infinite-state Stochastic Reachability Games

We consider perfect-information reachability stochastic games for 2 players on infinite graphs. We identify a subclass of such games, and prove two interesting properties of it: first, Player Max always has optimal strategies in games from this subclass, and second, these games are strongly determined. The subclass is defined by the property that the set of all values can only have one accumulation point -- 0. Our results nicely mirror recent results for finitely-branching games, where, on the contrary, Player Min always has optimal strategies. However, our proof methods are substantially different, because the roles of the players are not symmetric. We also do not restrict the branching of the games. Finally, we apply our results in the context of recently studied One-Counter stochastic games

Evolución de factores competitivos de la empresa familiar ante cambios en la propiedad: el caso mexicano estudiado en Estado de México, Tamaulipas, Quintana Roo y Puebla

El interés creciente por hacer perdurar las actividades económicas de la empresa familiar conduce gradualmente a realizar mayores esfuerzos de investigación con la finalidad de mejorar su comprensión y conocimiento para así reducir su vulnerabilidad. El presente trabajo se inscribe en la Teoría de los Recursos y Capacidades y se interesa en conocer la evolución de algunos factores internos a la empresa familiar relacionados con la competitividad y el cambio de propiedad en cuatro estados de México. Este documento es el resultado del trabajo colectivo de una red de investigación, cuyos autores pertenecen a la Universidad Anáhuac, Universidad Autónoma de Tamaulipas, Universidad de Quintana Roo y Universidad de las Américas.

Los programas de Interculturalidad. Una construcción desde sus actores

El presente documento expone de manera sintética los resultados la primera etapa de una investigación – acción que se está desarrollando con profesores del medio indígena en la sierra tarahumara. La etapa centró su atención en cómo enfrentar los retos de la interculturalidad que exige el nuevo contexto social a partir del desarrollo de programas educativos que coadyuven a resolver la problemática concreta que representa el bilingüismo la cual, se identificó como la problemática principal que enfrentan los actores educativos, así como la comunidad. El documento describe cómo se llevó a cabo la construcción de las acciones pedagógicas, las formas de evaluar y cómo se replantearon los proyectos generados por la colectividad