Sex Differences in the Drinking Response to Angiotensin II (AngII): Effect of Body Weight

Sex differences in fluid intake stimulated by angiotensin II (AngII) have been reported, but the direction of the differences is inconsistent. To resolve these discrepancies, we measured water intake by male and female rats given AngII. Males drank more than females, but when intake was normalized to body weight, the sex difference was reversed. Weight-matched males and females, however, had no difference in intake. Using a linear mixed model analysis, we found that intake was influenced by weight, sex, and AngII dose. We used linear regression to disentangle these effects further. Comparison of regression coefficients revealed sex and weight differences at high doses of AngII. Specifically, after 100ng AngII, weight was a predictor of intake in males, but not in females. Next, we tested for differences in AngII-induced intake in male and females allowed to drink both water and saline. Again, males drank more water than females, but females showed a stronger preference for saline. Drinking microstructure analysis suggested that these differences were mediated by postingestive signals and more bottle switches by the females. Finally, we probed for differences in the expression of components of the renin-angiotensin system in the brains of males and females and found sex differences in several genes in discrete brain regions. These results provide new information to help understand key sex differences in ingestive behaviors, and highlight the need for additional research to understand baseline sex differences, particularly in light of the new NIH initiative to balance sex in biomedical research

The Anti-Dipsogenic and Anti-Natriorexigenic Effects of Estradiol, but Not the Anti-Pressor Effect, Are Lost in Aged Female Rats

Estradiol (E2) inhibits fluid intake in several species, which may help to defend fluid homeostasis by preventing excessive extracellular fluid volume. Although this phenomenon is well established using the rat model, it has only been studied directly in young adults. Because aging influences the neuronal sensitivity to E2 and the fluid intake effects of E2 are mediated in the brain, we tested the hypothesis that aging influences the fluid intake effects of E2 in female rats. To do so, we examined water and NaCl intake in addition to the pressor effect after central angiotensin II treatment in young (3-4 months), middle-aged (10-12 months), and old (16-18 months) ovariectomized rats treated with estradiol benzoate (EB). As expected, EB treatment reduced water and NaCl intake in young rats. EB treatment, however, did not reduce water intake in old rats, nor did it reduce NaCl intake in middle-aged or old rats. The ability of EB to reduce blood pressure was, in contrast, observed in all three age groups. Next, we also measured the gene expression of estrogen receptors (ERs) and the angiotensin type 1 receptor (AT1R) in the areas of the brain that control fluid balance. ERβ, G protein estrogen receptor (GPER), and AT1R were reduced in the paraventricular nucleus of the hypothalamus in middle-aged and old rats, compared to young rats. These results suggest the estrogenic control of fluid intake is modified by age. Older animals lost the fluid intake effects of E2, which correlated with decreased ER and AT1R expression in the hypothalamus

DETERMINACIÓN DE LA CORROSIÓN DE UN SISTEMA O2-SALMUERA-ACERO AISI 1020, EN UNA CELDA DE IMPACTO HIDRODINÁMICA

RESUMENExisten pocas correlaciones para predecir los valores de los coefcientes de transferencia de masa y esfuerzo de corte en los estudios de corrosión de laboratorio que no han sido validadas para todos los sistemas corrosivos, y además no se encuentran expresiones que describan la velocidad de corrosión en función de dichos parámetros. En este trabajo se determinaron los valores de transferencia de masa y esfuerzo de corte en la pared por medio de la corriente límite y se compararon con los predichos en correlaciones para la geometría de la celda de impacto. Se calcularon las velocidades de corrosión para cada una de las condiciones evaluadas. La reacción de corrosión del mecanismo de control mixto estuvo parcialmente controlada por la transferencia de masa y carga, por lo que no todas las correlaciones se ajustaron a los resultados. Además se obtuvo una relación matemática entre la velocidad de corrosión, las variables hidrodinámicas y de transferencia de masa.Palabras claves: Transferencia de Masa, Esfuerzo de Corte en la Pared, Corriente Límite Electroquímica. ABSTRACTThe correlations to predict the coeffcients values of mass transfer and shear stress in laboratory studies of corrosion have not been validated for all systems and are not terms that describe the corrosion rate on the basis of these parameters. In this work the values of mass transfer and shear stress in the wall by using the current limit and were compared with those predicted in correlations for the geometry of the cell of impact. Corrosion rates for each of the conditions tested were calculated. The reaction of the corrosion mechanism of joint control was partially controlled by mass transfer and charge, so not all the correlations were adjusted with the results. A mathematical relationship between the corrosion rate of the hydrodynamic variables and mass transfer was obtained.Keywords: Mass Transfer, Shear Stress, Electrochemical Limit Current.

Negligencia medica en Essalud - hospital Almanzor Aguinaga Asenjo Chiclayo

El presente Trabajo de Investigación ha sido abordado y los hemos denominado “Negligencia Medica ESSALUD- Hospital Almanzor Aguinaga Asenjo Chiclayo”, Nuestro objetivo en la Presente Investigación Científica es, poder fijar un además de elaborar un marco conceptual de referencia, precisar el significado y alcance de algunos de los conceptos que serán utilizados en el estudio de los problemas presentados en la negligencia médica en nuestro departamento, tanto en la responsabilidad de aquellos quienes están involucrados, por lo cual resulta necesario conocer el entorno en que se producen, las razones por las cuales se verifican, así como distinguir los casos en que éstos no se suceden realmente. En consecuencia, se revisarán los conceptos de derecho, sistema jurídico, norma, aplicación y eficacia, entre otros, en virtud de su estrecha relación con los conflictos normativos. Por tanto, el estudio de este problema lo consideramos de sumo valor y actualidad, y sus resultados deben conducir a un necesario replanteamiento legal que permita una regulación acorde con lo que estableced la Legislación Comparada.Tesi

DETERMINACIÓN DE LA CORROSIÓN DE UN SISTEMA O2-SALMUERA-ACERO AISI 1020, EN UNA CELDA DE IMPACTO HIDRODINÁMICA

RESUMENExisten pocas correlaciones para predecir los valores de los coefcientes de transferencia de masa y esfuerzo de corte en los estudios de corrosión de laboratorio que no han sido validadas para todos los sistemas corrosivos, y además no se encuentran expresiones que describan la velocidad de corrosión en función de dichos parámetros. En este trabajo se determinaron los valores de transferencia de masa y esfuerzo de corte en la pared por medio de la corriente límite y se compararon con los predichos en correlaciones para la geometría de la celda de impacto. Se calcularon las velocidades de corrosión para cada una de las condiciones evaluadas. La reacción de corrosión del mecanismo de control mixto estuvo parcialmente controlada por la transferencia de masa y carga, por lo que no todas las correlaciones se ajustaron a los resultados. Además se obtuvo una relación matemática entre la velocidad de corrosión, las variables hidrodinámicas y de transferencia de masa.Palabras claves: Transferencia de Masa, Esfuerzo de Corte en la Pared, Corriente Límite Electroquímica. ABSTRACTThe correlations to predict the coeffcients values of mass transfer and shear stress in laboratory studies of corrosion have not been validated for all systems and are not terms that describe the corrosion rate on the basis of these parameters. In this work the values of mass transfer and shear stress in the wall by using the current limit and were compared with those predicted in correlations for the geometry of the cell of impact. Corrosion rates for each of the conditions tested were calculated. The reaction of the corrosion mechanism of joint control was partially controlled by mass transfer and charge, so not all the correlations were adjusted with the results. A mathematical relationship between the corrosion rate of the hydrodynamic variables and mass transfer was obtained.Keywords: Mass Transfer, Shear Stress, Electrochemical Limit Current.

Amelioration of Binge Eating by Nucleus Accumbens Shell Deep Brain Stimulation in Mice Involves D2 Receptor Modulation

Hedonic overconsumption contributing to obesity involves altered activation within the mesolimbic dopamine system. Dysregulation of dopamine signaling in the nucleus accumbens shell (NAS) has been implicated in reward-seeking behaviors, such as binge eating, which contributes to treatment resistance in obesity (Wise, 2012). Direct modulation of the NAS with deep brain stimulation (DBS), a surgical procedure currently under investigation in humans for the treatment of major depression, obsessive–compulsive disorder, and addiction, may also be effective in ameliorating binge eating. Therefore, we examined the ability of DBS of the NAS to block this behavior in mice. c-Fos immunoreactivity was assessed as a marker of DBS-mediated neuronal activation. NAS DBS was found to reduce binge eating and increased c-Fos levels in this region. DBS of the dorsal striatum had no influence on this behavior, demonstrating anatomical specificity for this effect. The dopamine D2 receptor antagonist, raclopride, attenuated the action of DBS, whereas the D1 receptor antagonist, SCH-23390, was ineffective, suggesting that dopamine signaling involving D2 receptors underlies the effect of NAS DBS. To determine the potential translational relevance to the obese state, chronic NAS DBS was also examined in diet-induced obese mice and was found to acutely reduce caloric intake and induce weight loss. Together, these findings support the involvement of the mesolimbic dopamine pathways in the hedonic mechanisms contributing to obesity, and the efficacy of NAS DBS to modulate this system

Inactivation of the melanin concentrating hormone system impairs maternal behavior

In order to prepare the mother for the demands of pregnancy and lactation, the maternal brain is subjected to a number of adaptations. Maternal behaviors are regulated by complex neuronal interactions. Here, we show that the melanin concentrating hormone (MCH) system is an important regulator of maternal behaviors. First, we report that melanin concentrating hormone receptor 1 knockout (MCHR1 KO) mice display a disruption of maternal behavior. Early postpartum MCHR1 KO females exhibit poor nesting, deficits in pup retrieval and maternal aggression. In addition, ablation of MCH receptors results in decreased milk production and prolactin mRNA levels. Then we show that these results are in line with those obtained in wild type mice (WT) treated with the specific MCHR1 antagonist GW803430. Furthermore, following pups retrieval, MCHR1 KO mice display a lower level of Fos expression than WT mice in the ventral tegmental area, and nucleus accumbens. With the progression of the lactation period, however, the MCHR1 KO mice improve maternal care towards their pups. This is manifested by an increase in the pups׳ survival rate and the decrease in pups׳ retrieval time beyond the second day after parturition. In conclusion, we show that the MCH system plays a significant role in the initiation of maternal behavior. In this context, MCH may play a role in integrating information from multiple sources, and connecting brain reward, homeostatic and regulatory systems