Effects of Cannabinoids on Caffeine Contractures in Slow and Fast Skeletal Muscle Fibers of the Frog

The effect of cannabinoids on caffeine contractures was investigated in slow and fast skeletal muscle fibers using isometric tension recording. In slow muscle fibers, WIN 55,212-2 (10 and 5 μM) caused a decrease in tension. These doses reduced maximum tension to 67.43 ± 8.07% (P = 0.02, n = 5) and 79.4 ± 14.11% (P = 0.007, n = 5) compared to control, respectively. Tension-time integral was reduced to 58.37 ± 7.17% and 75.10 ± 3.60% (P = 0.002, n = 5), respectively. Using the CB1 cannabinoid receptor agonist ACPA (1 μM) reduced the maximum tension of caffeine contractures by 68.70 ± 11.63% (P = 0.01, n = 5); tension-time integral was reduced by 66.82 ± 6.89% (P = 0.02, n = 5) compared to controls. When the CB1 receptor antagonist AM281 was coapplied with ACPA, it reversed the effect of ACPA on caffeine-evoked tension. In slow and fast muscle fibers incubated with the pertussis toxin, ACPA had no effect on tension evoked by caffeine. In fast muscle fibers, ACPA (1 μM) also decreased tension; the maximum tension was reduced by 56.48 ± 3.4% (P = 0.001, n = 4), and tension-time integral was reduced by 57.81 ± 2.6% (P = 0.006, n = 4). This ACPA effect was not statistically significant with respect to the reduction in tension in slow muscle fibers. Moreover, we detected the presence of mRNA for the cannabinoid CB1 receptor on fast and slow skeletal muscle fibers, which was significantly higher in fast compared to slow muscle fiber expression. In conclusion, our results suggest that in the slow and fast muscle fibers of the frog cannabinoids diminish caffeine-evoked tension through a receptor-mediated mechanism

POTENCIALES DE ACCION Y ACOPLE EXCITACION CONTRACCION EN FIBRA MUSCULAR ESQUELÉTICA DE ANFIBIO

Facultad de Medicin

Interleucina-12 exógena evita disminución de actividad de mieloperoxidasa de macrófagos en gérbiles con esporotricosis

Introduction: interleukin-12 is an immunoregulatory cytokine with multiple biologic functions, including macrophage activation. Myeloperoxidase is an enzyme that plays an important role in the antimicrobial function of activated phagocytes. In the presence of hydrogen peroxide, myeloperoxidase catalyzes chloride oxidation to produce hypochlorous acid, a powerful microbicidal agent. Objective: determine the stimulating effect of murine recombinant interleukin-12 on myeloperoxidase activity in peritoneal macrophages of gerbils experimentally infected with Sporothrix schenckii yeasts. Methods: 500 ng murine recombinant interleukin-12 were administered intraperitoneally on a daily basis on 5 consecutive days to male gerbils. On the sixth day the gerbils were inoculated subcutaneously on the left posterior plantar pad with 6x106 S. schenckii yeasts. Seven days after infection, macrophages were obtained from the peritoneal cavity. Myeloperoxidase activity was determined by Kaplow's method and expressed as percentage of peritoneal macrophage activity. Results are expressed as the average percentage of myeloperoxidase activity ± standard deviation from 3 independent experiments. Statistical differences between groups were evaluated by Student's t test. A value of p < 0.05 was considered significant. Results: administration of murine recombinant interleukin-12 to gerbils following infection with S. schenckii significantly increased the myeloperoxidase activity of peritoneal macrophages (p = 0.0001) in comparison with healthy controls. Macrophages of untreated infected gerbils, however, showed significantly reduced myeloperoxidase activity in comparison with healthy controls (p= 0.001), suggesting poor macrophage activation. Conclusions: in vivo administration of murine recombinant interleukin-12 before infection with S. schenckii induces macrophage activation evidenced by an increase in myeloperoxidase activity, enhancing the organism's defense against that infectious agent via the myeloperoxidase-dependent oxidative system.Introducción: la interleucina-12 es una citosina inmunorreguladora con múltiples funciones biológicas, incluyendo la activación de macrófagos. La mieloperoxidasa es una enzima que desempeña un papel importante en la función antimicrobiana de fagocitos activados. En presencia de peróxido de hidrógeno, esta cataliza la oxidación de cloruro para generar ácido hipocloroso, potente agente microbicida. Objetivo: determinar el efecto estimulador de interleucina-12 recombinante murina sobre la actividad de mieloperoxidasa en macrófagos peritoneales en gérbiles infectados experimentalmente con levaduras de Sporothrix schenckii. Métodos: 500 ng de interleucina-12 recombinante murina fueron suministrados diariamente por vía intraperitoneal durante 5 días consecutivos a gérbiles machos, los cuales al sexto día fueron inoculados por vía subcutánea en el cojinete plantar posterior izquierdo con 6x106 levaduras de S. schenckii. siete días después de la infección los macrófagos fueron obtenidos de la cavidad peritoneal y la actividad de su mieloperoxidasa fue determinada mediante el método de Kaplow, expresándose como porcentaje de actividad de macrófagos peritoneales. Los resultados son expresados como el promedio del por ciento de actividad de mieloperoxidasa ± desviación estándar de 3 experimentos independientes. Las diferencias estadísticas entre grupos fueron evaluadas por medio de t de Student y un valor de p < 0,05 fue considerado significativo. Resultados: la administración de interleucina-12 recombinante murina a gérbiles previa infección con S. schenckii aumentó significativamente la actividad de mieloperoxidasa de macrófagos peritoneales (p = 0,0001) comparada con los controles sanos. En contraste, macrófagos de gérbiles infectados no tratados mostraron actividad de mieloperoxidasa significativamente disminuida comparada con los controles sanos (p= 0,001), lo cual sugiere activación deteriorada de macrófagos. Conclusiones: la administración in vivo de interleucina-12 recombinante murina antes de la infección con S. schenckii, induce activación de macrófagos evidenciada por un aumento en la actividad de mieloperoxidasa, lo que contribuiría a la defensa del organismo contra este agente infeccioso vía sistema oxidativo dependiente de mieloperoxidasa

Envejecimiento y capacidad funcional en adultos mayores institucionalizados del occidente de México

Objectives. To identify, in older adults living in care centers in 3 western Mexican states, the functional capacity to perform 10 basic daily activities. Material and methods. A multicenter, cross-sectional descriptive study was conducted on 373 older adults from the states of Colima (n=151), Nayarit (n=111), and Jalisco (n=111). Through non-probability sampling (convenience sampling) and after obtaining informed consent, the Barthel scale was applied in order to identify functional capacity level. The demographic variables and the dominance level of each daily activity were analyzed using descriptive statistics. The chi-square test was employed to compare the physical functionality proportions based on sex.Statistically significant difference was set at a p≤ 0.05. Results. For Colima, the unctional capacity in the categories of total independence and mild, moderate, and severe dependence were (%): 10.6, 52.3, 15.9, 7.3, and 13.9, respectively; for Nayarit (%): 13.5, 41.4, 19.8, 9.90, and 15.3, respectively; and for Jalisco (%): 27.9, 28.8, 14.4, 18.0, and 10.8, respectively. The differences based on sex were only significant for the state of Nayarit (p= de 0.000). The daily life activity with the highest proportion of totally independent subjects was “eating”, and the activities with the most totally dependent subjects were “going up and down stairs” and “bathing”. Conclusions. Functional limitation is a natural part of the aging process and it is important to systematically apply the Barthel scale to older adults living in care centers because it is a relevant tool for identifying motor function deficit in these persons.Objetivo. Identificar la capacidad funcional para realizar 10 actividades básicas de la vida diaria en adultos mayores institucionalizados de 3 diferentes Estados del Occidente de México. Material y métodos. Estudio trasversal descriptivo, multicéntrico realizado en 373 adultos mayores de los Estados de Colima (n=151), Nayarit (n=111) y Jalisco n=111) en los que mediante un muestreo no probabilístico por conveniencia y previo consentimiento informado, se aplicó la escala de Barthel para identificar su nivel de apacidad funcional. Estadística descriptiva fue utilizada para analizar variables demográficas y nivel de dominio de cada actividad de la vida diaria. Chi cuadrado para comparar proporciones de funcionalidad física con base a géneros. Se consideraron significativas las diferencias cuando p≤ 0.05. Resultados. La capacidad funcional para las categorías: independencia total, dependencia leve, moderada, severa y total, fueron para Colima (%): 10.6, 52.3, 15.9, 7.3 y 13.9 respectivamente. Para Nayarit (%): 13.5, 41.4, 19.8, 9.90 y 15.3. Para Jalisco (%): 27.9,28.8, 14.4, 18.0 y 10.8 respectivamente. Las diferencias con base a género, fue significativa únicamente para el estado de Nayarit (p= de 0.000). La actividad de la vida diaria que presentó mayor proporción de sujetos independientes totales fue “comer”, en tanto que “subir-bajar escaleras y lavarse” fueron las que registraron más sujetos dependientes totales. Conclusión. La limitación funcional es un proceso natural del envejecimiento y es importante que de manera sistemáticase aplique la escala de Barthel al adulto mayor institucionalizado, ya que ha demostrado ser relevante para identificar déficit funcional motor en estas persona

Capacidad funcional en adultos mayores residentes en asilos y casas de cuidado del estado de Nayarit

The physiological aging of a person is conditioned by multiple diseases, mainly chronic degenerative diseases, which generates a situation of dependence on the elderly (AM) that affects their quality of life. It is due to this series of changes that the AM experiences progressive alterations in its coping mechanisms, which often results in problems of physical, psychological and social adaptation at this stage of its life.El envejecimiento fisiológico de una persona se ve condicionado por múltiples enfermedades, principalmente crónico degenerativas, lo cual genera una situación de dependencia en el adulto mayor (AM) que repercute en su calidad de vida. Es debido a esta serie de cambios, que el AM experimenta de manera progresiva alteraciones en sus mecanismos de afrontamiento, lo que da como resultado frecuentemente problemas de adaptación física, psicológica y social en esta etapa de su vida

Considerations and consequences of allowing DNA sequence data as types of fungal taxa

Nomenclatural type definitions are one of the most important concepts in biological nomenclature. Being physical objects that can be re-studied by other researchers, types permanently link taxonomy (an artificial agreement to classify biological diversity) with nomenclature (an artificial agreement to name biological diversity). Two proposals to amend the International Code of Nomenclature for algae, fungi, and plants (ICN), allowing DNA sequences alone (of any region and extent) to serve as types of taxon names for voucherless fungi (mainly putative taxa from environmental DNA sequences), have been submitted to be voted on at the 11th International Mycological Congress (Puerto Rico, July 2018). We consider various genetic processes affecting the distribution of alleles among taxa and find that alleles may not consistently and uniquely represent the species within which they are contained. Should the proposals be accepted, the meaning of nomenclatural types would change in a fundamental way from physical objects as sources of data to the data themselves. Such changes are conducive to irreproducible science, the potential typification on artefactual data, and massive creation of names with low information content, ultimately causing nomenclatural instability and unnecessary work for future researchers that would stall future explorations of fungal diversity. We conclude that the acceptance of DNA sequences alone as types of names of taxa, under the terms used in the current proposals, is unnecessary and would not solve the problem of naming putative taxa known only from DNA sequences in a scientifically defensible way. As an alternative, we highlight the use of formulas for naming putative taxa (candidate taxa) that do not require any modification of the ICN.Peer reviewe