Search

The sequence of concurrent training sessions is a determining variable in physiological adaptations; however, its effects on body composition and physical condition have been little explored in older women. For this reason, the primary aim of this research is to determine the effects of the intrasession exercise sequence of concurrent training on older women’s body composition and physical fitness. The present study was conducted under a randomized experimental design. The population sample consisted of 38 physically inactive women aged between 60 and 75 years. These women were randomly assigned to one of the training groups: strength + endurance (SE, n = 19) or endurance + strength (ES, n = 19.) The intervention was the same for both training groups; the only difference was the exercise sequence of both components: one group first trained strength and then endurance, and the other did the opposite. The variables evaluated before and after the intervention were body composition and physical fitness. A two-way repeated measures ANOVA was used to determine statistically significant differences in pre- and post-test means within each group. Cohen’s d effect size was also calculated to determine the magnitude of the group differences. The ES group had significant differences in mass (p = 0.036, d = 0.834), fat percentage (p = 0.044, d = 0.419), arm curl (p = 0.041, d = 1.429), step (p = 0.023, d = 1.423), and grip strength (p = 0.001, d = 0.831). The SE group reported significant differences in mass (p = 0.035, d = 0.545), fat percentage (p = 0.023, d = 0.882), muscle percentage (p = 0.001, d = 3.536), chair stand (p = 0.001, d = 2.579), arm curl (p = 0.001, d = 1.530), step (p = 0.001, d = 1.369), and grip strength (p = 0.001, d = 0.85). When comparing the effects of the two interventions, strength followed by endurance training was more effective in: fat percentage, arm curl, chair sit-and-reach (cm) the muscle percentage and chair stand variables. The main conclusion of this research is that concurrent training starting with strength followed by endurance, in older women, is more effective in improving body composition and physical condition compared to endurance training followed by strength. Resumen. La secuencia de las sesiones de entrenamiento concurrente es una variable determinante en las adaptaciones fisiológicas; sin embargo, sus efectos sobre la composición corporal y la condición física se han explorado poco en mujeres mayores. Por esta razón, el objetivo del texto es determinar los efectos de la secuencia de ejercicios intrasesión del entrenamiento concurrente sobre la composición corporal y la aptitud física de las mujeres mayores. El presente estudio se realizó bajo un diseño experimental aleatorizado. La muestra poblacional estuvo conformada por 38 mujeres físicamente inactivas de entre 60 y 75 años. Estas mujeres fueron asignadas al azar a uno de los grupos de entrenamiento: fuerza + resistencia (FR, n = 19) o resistencia + fuerza (RF, n = 19.) La intervención fue la misma para ambos grupos de entrenamiento; la diferencia fue la secuencia de los ejercicios. Las variables evaluadas antes y después de la intervención fueron la composición corporal y la forma física. Se utilizó un ANOVA de medidas repetidas de dos factores para determinar diferencias estadísticamente significativas en las medias antes y después de la prueba dentro de cada grupo. El tamaño del efecto d de Cohen, se calculó para determinar la magnitud de las diferencias de grupo. El grupo RF tuvo diferencias significativas en las variable de peso (p = 0.036, d = 0.834), porcentaje de grasa (p = 0.044, d = 0.419), flexión de brazos (p = 0.041, d = 1.429), paso (sp = 0.023, d = 1.423) y fuerza de agarre (p = 0.001, d = 0.831). El grupo FR reportó diferencias significativas en peso (p = 0.035, d = 0.545), porcentaje de grasa (p = 0.023, d = 0.882), porcentaje de músculo (p = 0.001, d = 3.536), en soporte de silla (p = 0.001, d = 2.579), flexión de brazos (p = 0.001, d = 1.530), pasos (p = 0.001, d = 1.369) y fuerza de agarre (p = 0.001, d = 0.85). Al comparar los efectos de las dos intervenciones, el entrenamiento de fuerza seguido del entrenamiento de resistencia fue más efectivo en: porcentaje de grasa, flexiones de brazos, sentarse y alcanzar la silla , porcentaje muscular y pararse de una silla. La principal conclusión de esta investigación es que el entrenamiento concurrente que comienza con fuerza seguido de resistencia, en mujeres mayores, es más efectivo para mejorar la composición corporal y la condición física en comparación con el entrenamiento de resistencia seguido de fuerza. Al comparar los efectos de las dos intervenciones, la fuerza seguida por el entrenamiento de resistencia fue más efectiva en las variables de porcentaje muscular y soporte en silla. La principal conclusión de esta investigación es que el entrenamiento concurrente en mujeres mayores es más efectivo para el porcentaje de músculos y la prueba de apoyo en silla cuando el orden de la sesión es la fuerza seguida por el entrenamiento de resistencia.

Early life stress induced by maternal separation (MS) causes neuroendocrine, behavioral, and metabolic alterations that are related to gut dysbiosis. MS also increases microglial activation and decreases neurogenesis. Whether these long-term alterations are maintained or worsened in the absence of gut microbiota remains unknown. Hence, this study evaluated the effect of MS symptomatology after antibiotic-induced microbiota depletion (AIMD) in adult rats. Control and maternally separated (3 h per day from postnatal day one to 14, MS180) rats were subjected to AIMD for one month, then assessed for behavioral, metabolic, and neuroendocrine responses. Effects of MS180 and AIMD on gut microbiota were confirmed by qPCR. The data indicate that MS180 caused a passive coping strategy in the forced swimming test and decreased hippocampal neurogenesis. In addition, fasting glucose, cholesterol, and corticosterone levels increased, which correlated with a decrease in Lactobacillus spp counts in the caecum. AIMD also increased immobility in the forced swimming test, decreased hippocampal neurogenesis, and augmented corticosterone levels. However, it had no effects on glucose homeostasis or plasma lipid levels. Furthermore, the MS180-induced long-term effects on behavior and neurogenesis were not affected by microbiota depletion. Meanwhile, the metabolic imbalance was partially reversed in MS180 + AIMD rats. These results show that AIMD mimics the behavioral consequences of MS180 but may prevent metabolic imbalance, suggesting that gut dysbiosis could be part of the mechanisms involved in the maintenance of the long-term consequences of early life stress.

La expresión cultura digital ha tomado fuerza en los últimos años en diversos trabajos académicos. Sin embargo, al menos en Iberoamérica, es utilizada para referir un contexto de ocurrencia de fenómenos actuales, sin que existan suficientes acercamientos teóricos o epistemológicos que clarifiquen su constitución. Para contribuir a la articulación de la investigación académica en torno a la cultura digital como objeto de estudio, un grupo de investigadores del Sistema de Universidad Virtual de la Universidad de Guadalajara que trabajamos en esta línea decidimos realizar una invitación a colegas y estudiantes de diversas instituciones de educación superior de México y América Latina, con el fin de presentar avances y resultados de investigaciones en relación con este objeto de estudio. Este libro recoge algunos de los trabajos, cuya selección obedece, sobre todo, a la intención de brindar pistas en tres sentidos fundamentales: (i) acercamientos epistemológicos para el estudio de la cultura digital desde su especificidad que se aparten de lógicas dicotómicas entre cultura y tecnologías digitales; (ii) aproximaciones históricas que contribuyan a la clarificación respecto de los vacíos conceptuales y metodológicos sobre la cultura digital; y (iii) la delimitación de objetos de estudio posibles construidos desde la cultura digital, así como esbozos metodológicos para su abordaje. El texto está organizado en seis capítulos. En el primero de ellos, Janny Amaya Trujillo y Blanca Estela Chávez Blanco presentan un acercamiento epistemológico al estudio de la cultura digital situándola como objeto de estudio. A partir del reconocimiento teórico de expresiones equivalentes como cibercultura, sociedad red o cultura de la convergencia, las autoras destacan la preponderancia presente en estas posturas de entender la cultura actual bajo las lógicas que marcan las tecnologías, principalmente digitales, y las improntas hacia una cultura participativa, democrática y transparente. Como alternativa a la visión causalista y dicotómica en la comprensión de la cultura digital, plantean que esta se puede entender como “construcciones sociales de sentido que determinan las acciones humanas”, mostrando así la existencia de determinados rasgos problemáticos que distinguen a la cultura digital y que la sitúan como una nueva conformación cultural.

Resumen Introducción: la neumonía adquirida en la comunidad es una infección aguda del parénquima pulmonar que corresponde a una importante causa de morbi-mortalidad en Colombia. En esta entidad, se ha asociado la pobre calidad en la atención y la mala adherencia a las guías de manejo con un impacto negativo tanto en el desenlace clínico del paciente, como en la academia y solvencia económica de un Hospital Universitario. Objetivo: describir la calidad de la atención médica y adherencia a la guía colombiana de manejo de la neumonía adquirida en la comunidad en el Hospital Universitario de Santander durante el periodo 2014-2015. Materiales y métodos: estudio descriptivo de corte transversal; se seleccionaron 121 historias clínicas con diagnóstico de Neumonía Adquirida en la Comunidad en el Hospital Universitario de Santander durante el periodo 2014-2015. A partir de estas, se recolectaron variables respecto a la aproximación diagnóstica, asignación de tratamiento y recomendaciones generales, evaluando por cada ítem individual el porcentaje de adherencia a la guía de Neumonía adquirida en la comunidad de la Asociación Colombiana de Infectología y los criterios de calidad en la atención de la Community Acquired Pneumonia Organization. Resultados: los ítems con mayor cumplimiento fueron: el hemoleucograma (100%) y la toma de radiografía de tórax (98%). Por otra parte, la clasificación CURB-65 (15%), la indicación de radiografía de tórax en el control (12%) y las recomendaciones para cese de tabaquismo y vacunación (0%) fueron los parámetros con menor rendimiento. Conclusiones: se evidenció una falencia en el proceso de clasificación clínica del paciente, condición que, asociada al escaso uso de laboratorios de diagnóstico microbiológico y el excesivo uso de estudios de imagen no indicados como la tomografía computarizada, favorece un tratamiento ineficiente y el desarrollo de resistencia farmacológica. MÉD.UIS.2019;32(2):23-30 Abstract Introduction: community-acquired pneumonia is an acute infection of lung parenchyma, being nowadays an important cause of morbidity and mortality in Colombia. In this entity, poor health care quality and poor adherence to management guidelines has been associated with a negative impact on both, the clinical outcome of the patient and the academic and financial solvency of a university hospital. Objective: to describe the quality of medical care and adherence to the Colombian community-acquired pneumonia guideline in the Hospital Universitario de Santander during the 2014-2015 period. Methods: descriptive cross-sectional study. 121 clinical records with diagnosis of community-acquired pneumonia in the Hospital Universitario de Santander were selected. Variables regarding diagnostic approach, treatment assignment and general recommendations were collected from these, evaluating for each item the proportion of adherence to the guideline as well as the quality criteria in medical care defined by the Community Acquired Pneumonia Organization. Results: items with best reported adherence were: complete blood count (100%) and chest X-ray (98%). On the other hand, CURB-65 classification (15%), chest X-ray indicated for the ambulatory control (12%), as well as recommendations for cessation of smoking and vaccination (0%), were the parameters with the lowest performance. Conclusions: there was evidence of failure in the clinical classification of the patient, which was associated with poor use of microbiological diagnostic laboratories and overuse of imaging studies such as computed tomography, thus favoring inefficient treatment and development of bacterial pharmacological resistance. MÉD.UIS.2019;32(2):23-30

Bayesian statistics and Markov Chain Monte Carlo (MCMC) algorithms have found their place in the field of Cosmology. They have become important mathematical and numerical tools, especially in parameter estimation and model comparison. In this paper, we review some fundamental concepts to understand Bayesian statistics and then introduce MCMC algorithms and samplers that allow us to perform the parameter inference procedure. We also introduce a general description of the standard cosmological model, known as the $\Lambda$CDM model, along with several alternatives, and current datasets coming from astrophysical and cosmological observations. Finally, with the tools acquired, we use an MCMC algorithm implemented in python to test several cosmological models and find out the combination of parameters that best describes the Universe., Comment: 30 pages, 17 figures, 5 tables; accepted for publication in Universe; references added

Bariatric surgery remains the single most effective long-term treatment modality for morbid obesity, achieved mainly by lowering caloric intake through as yet ill-defined mechanisms. Here we show in rats that Roux-en-Y gastric bypass (RYGB)-like rerouting of ingested fat mobilizes lower small intestine production of the fat-satiety molecule oleoylethanolamide (OEA). This was associated with vagus nerve-driven increases in dorsal striatal dopamine release. We also demonstrate that RYGB upregulates striatal dopamine 1 receptor (D1R) expression specifically under high-fat diet feeding conditions. Mechanistically, interfering with local OEA, vagal, and dorsal striatal D1R signaling negated the beneficial effects of RYGB on fat intake and preferences. These findings delineate a molecular/systems pathway through which bariatric surgery improves feeding behavior and may aid in the development of novel weight loss strategies that similarly modify brain reward circuits compromised in obesity.

Sugars that contain glucose, such as sucrose, are generally preferred to artificial sweeteners owing to their post-ingestive rewarding effect, which elevates striatal dopamine (DA) release. While the post-ingestive rewarding effect, which artificial sweeteners do not have, signals the nutrient value of sugar and influences food preference, the neural circuitry that mediates the rewarding effect of glucose is unknown. In this study, we show that optogenetic activation of melanin-concentrating hormone (MCH) neurons during intake of the artificial sweetener sucralose increases striatal dopamine levels and inverts the normal preference for sucrose vs sucralose. Conversely, animals with ablation of MCH neurons no longer prefer sucrose to sucralose and show reduced striatal DA release upon sucrose ingestion. We further show that MCH neurons project to reward areas and are required for the post-ingestive rewarding effect of sucrose in sweet-blind Trpm5−/− mice. These studies identify an essential component of the neural pathways linking nutrient sensing and food reward. DOI: http://dx.doi.org/10.7554/eLife.01462.001, eLife digest Sales of full-sugar fizzy drinks are almost triple those of diet versions, providing real-world confirmation of the laboratory finding that humans, as well as animals, prefer sugar to artificial sweeteners. However, it is not simply that sugary things taste better. Mice with a mutation that prevents them from perceiving sweet tastes still prefer the natural sugar sucrose over the artificial sweetener sucralose. This is because sugar, unlike artificial sweeteners, has nutritional value, and both humans and animals find it rewarding to consume foods with a high caloric content. Consuming sugar has been known to cause certain parts of the brain to release more of the chemical transmitter dopamine, which is used to signal reward, but exactly how this process produces a preference for sugar has been unclear. Now, Domingos et al. have revealed that a brain region called the lateral hypothalamus is responsible for this effect. This region of the brain—which helps to control appetite and which is also connected to the brain’s reward system—normally contains cells called MCH neurons. Domingos et al. show that the natural preference for sucrose over sucralose can be reversed by stimulating the MCH neurons with light, which in turn stimulates dopamine release in reward centers in the brain. Moreover, mutant mice that do not have any MCH neurons in the lateral hypothalamus show a reduced preference for sucrose over sucralose, compared to normal mice, and they release less dopamine than normal mice when they consume sucrose. By demonstrating that MCH neurons are both necessary and sufficient for sensing the nutritional value of sugar, these results provide new insights into the biological basis of sugar cravings. However, given the health implications of excessive sugar consumption, they may ultimately be used to find ways to make sugar less desirable, or to make artificial sweeteners more closely mimic the real thing. DOI: http://dx.doi.org/10.7554/eLife.01462.002

Background Autonomic modulation is a valuable therapeutic option for the management of ventricular arrhythmias. Bilateral cardiac sympathetic denervation (BCSD) has shown promising results in the acute, intermediate, and long-term management of polymorphic and monomorphic ventricular tachycardia (VT) in patients with structural heart disease. Cardiomyopathy (CM) due to Chagas disease (CD), and associated VT, is thought to be in part due to autonomic neuronal destruction and dysfunction. Objective The purpose of this study was to assess whether BCSD is a safe and effective treatment modality in patients with CD and VT storm or refractory VT. Methods A retrospective analysis of data from patients with chagasic CM who underwent BCSD between 2009 and 2015 at 2 international centers was performed. Results Of 75 patients who underwent BCSD for VT storm or refractory VT in the setting of CM, 7 (9.3%) patients had CD as the etiology of CM. All patients had monomorphic VT. Median follow-up was 7 months (range 1–46 months). All patients either underwent previous unsuccessful catheter ablation or were not candidates for ablation. The median number of implantable cardioverter-defibrillator (ICD) shocks 1 month before BCSD was 4 (range 2–30) and decreased to 0 (range 0–2) during available follow-up after BCSD. When antitachycardia pacing therapies were included in the analysis, the median number of ICD therapies (shocks + antitachycardia pacing) still decreased to 1 (range 0–3). Conclusion In patients with chagasic CM presenting with refractory monomorphic VT, early evidence suggests that BCSD reduces appropriate ICD therapy and may represent a valuable treatment option.

Numerical and experimental study to evaluate aerodynamic characteristics in supersonic ow over a double wedge airfoil is carried out using Fluent software and a supersonic wind tunnel, respectively. The Schlieren visualization method was also used to develop the experimental step of this study. The supersonic wind tunnel reached a proximately a Mach number of 1.8. The result got showed oblique shock waves visualization on double-wedge airfoil and the numerical simulation, the flow behavior as function of Mach number, pressure, temperature and density in the flow field on the computational model. The simulation allowed to observe the shock wave and the expansion fan in the leading and tailing edge of double-wedge airfoil. From the numerical and experimental comparison, an agreement at the shock wave angle and Mach number was observed, with a difference about 1.17% from the experimental results.

Reductions in calorie intake contribute significantly to the positive outcome of bariatric surgeries. However, the physiological mechanisms linking the rerouting of the gastrointestinal tract to reductions in sugar cravings remain uncertain. We show that a duodenal-jejunal bypass (DJB) intervention inhibits maladaptive sweet appetite by acting on dopamine-responsive striatal circuitries. DJB disrupted the ability of recurrent sugar exposure to promote sweet appetite in sated animals, thereby revealing a link between recurrent duodenal sugar influx and maladaptive sweet intake. Unlike ingestion of a low-calorie sweetener, ingestion of sugar was associated with significant dopamine effluxes in the dorsal striatum, with glucose infusions into the duodenum inducing greater striatal dopamine release than equivalent jejunal infusions. Consistently, optogenetic activation of dopamine-excitable cells of the dorsal striatum was sufficient to restore maladaptive sweet appetite in sated DJB mice. Our findings point to a causal link between striatal dopamine signaling and the outcomes of bariatric interventions.

Perezone had been used for centuries in the traditional Mexican medicine, it is useful and a handful of illness. Perezone and other derivatives also present activity against certain lines of cancer, such as the myeloblastoid leukemia cell line K-562 and carcinoma cell lines (PC-3 and SKLU-1) with IC50

Introduction Giant thoracic aortic aneurysms (TAA) are extremely uncommon, and there are only a few cases reported in the literature. Most patients presented with symptoms before the size of the aneurysm reached a magnitude >10 cm, and most of the reported cases were treated with open repair. Presentation of case Here we report a 15 cm asymptomatic thoracic aortic aneurysm of a 72-year-old male patient, treated successfully with thoracic endovascular aortic repair (TEVAR). The patient was discharged asymptomatic on postoperative day 2. Discussion Only 20 case reports of giant TAAs were found in the literature, and this is the biggest TAA reported treated with TEVAR. This procedure is a promising treatment as morbidity and mortality is lower when compared with open aortic repair (OAR). Conclusion Even though there is limited documented experience, use of TEVAR seems a safe and promising option in the treatment of giant thoracic aneurysms as presented in this case.

The rational designing of binding abilities in proteins requires an understanding of the relationship between structure and thermodynamics. However, our knowledge of the molecular origin of high-affinity binding of ligands to proteins is still limited; such is the case for L-lysine–L-arginine–L-ornithine periplasmic binding protein (LAOBP), a periplasmic binding protein from Salmonella typhimurium that binds to L-arginine, L-lysine, and L-ornithine with nanomolar affinity and to L-histidine with micromolar affinity. Structural studies indicate that ligand binding induces a large conformational change in LAOBP. In this work, we studied the thermodynamics of L-histidine and L-arginine binding to LAOBP by isothermal titration calorimetry. For both ligands, the affinity is enthalpically driven, with a binding ΔCp of ~� 300calmol � 1 K � 1 , most of which arises from the burial of protein nonpolar surfaces that accompanies the conformational change. Osmotic stress measurements revealed that several water molecules become sequestered upon complex formation. In addition, LAOBP prefers positively charged ligands in their side chain. An energetic analysis shows that the protein acquires a thermodynamically equivalent state with both ligands. The 1000-fold higher affinity of LAOBP for L-arginine as compared with L-histidine is mainly of enthalpic origin and can be ascribed to the formation of an extra pair of hydrogen bonds. Periplasmic binding proteins have evolved diverse energetic strategies for ligand recognition. STM4351, another arginine binding protein from Salmonella, shows an entropy-driven micromolar affinity toward L-arginine. In contrast, our data show that LAOBP achieves nanomolar affinity for the same ligand through enthalpy optimization. Copyright © 2015 John Wiley & Sons, Ltd. Additional supporting information may be found in the online version of this article at the publisher’s web site.

It is well established that animals including humans attribute greater reinforcing value to glucose-containing sugars compared to their non-caloric counterparts, generally termed 'artificial sweeteners'. However, much remains to be determined regarding the physiological signals and brain systems mediating the attribution of greater reinforcing value to sweet solutions that contain glucose. Here we show that disruption of glucose utilization in mice produces an enduring inhibitory effect on artificial sweetener intake, an effect that did not depend on sweetness perception or aversion. Indeed, such an effect was not observed in mice presented with a less palatable, yet caloric, glucose solution. Consistently, hungry mice shifted their preferences away from artificial sweeteners and in favour of glucose after experiencing glucose in a hungry state. Glucose intake was found to produce significantly greater levels of dopamine efflux compared to artificial sweetener in dorsal striatum, whereas disrupting glucose oxidation suppressed dorsal striatum dopamine efflux. Conversely, inhibiting striatal dopamine receptor signalling during glucose intake in sweet-naive animals resulted in reduced, artificial sweetener-like intake of glucose during subsequent gluco-deprivation. Our results demonstrate that glucose oxidation controls intake levels of sweet tastants by modulating extracellular dopamine levels in dorsal striatum, and suggest that glucose utilization is one critical physiological signal involved in the control of goal-directed sweetener intake.

The influence of micronutrients on dopamine systems is not well defined. Using mice, we show a potential role for reduced dietary vitamin D3 (cholecalciferol) in promoting diet-induced obesity (DIO), food intake, and drug consumption while on a high fat diet. To complement these deficiency studies, treatments with exogenous fully active vitamin D3 (calcitriol, 10 µg/kg, i.p.) were performed. Nondeficient mice that were made leptin resistant with a high fat diet displayed reduced food intake and body weight after an acute treatment with exogenous calcitriol. Dopamine neurons in the midbrain and their target neurons in the striatum were found to express vitamin D3 receptor protein. Acute calcitriol treatment led to transcriptional changes of dopamine-related genes in these regions in naive mice, enhanced amphetamine-induced dopamine release in both naive mice and rats, and increased locomotor activity after acute amphetamine treatment (2.5 mg/kg, i.p.). Alternatively, mice that were chronically fed either the reduced D3 high fat or chow diets displayed less activity after acute amphetamine treatment compared with their respective controls. Finally, high fat deficient mice that were trained to orally consume liquid amphetamine (90 mg/L) displayed increased consumption, while nondeficient mice treated with calcitriol showed reduced consumption. Our findings suggest that reduced dietary D3 may be a contributing environmental factor enhancing DIO as well as drug intake while eating a high fat diet. Moreover, these data demonstrate that dopamine circuits are modulated by D3 signaling, and may serve as direct or indirect targets for exogenous calcitriol.

Post-ingestive factors are known to strongly modulate feeding behavior by providing feedback signals to the central nervous system on the current physiological state of the organism. Of particular interest is the identification of the physiological pathways that permit the brain to sense post-ingestive signals. We will review recent evidence supporting the concept that direct stimulation of the gastrointestinal tract with nutrients induces release of the catecholamine neurotransmitter dopamine. In addition, changes in dopamine efflux produced by direct stimulation of the gastrointestinal tract were found to reflect the caloric load of the infusates, suggesting that dopamine signaling may function as a central caloric sensor that mediates adjustments in intake according to the caloric density of a meal. Consistent with the above, blockade of dopamine signaling disrupts flavor-nutrient associations and impairs the regulatory capacity to maintain constant caloric intake during intra-gastric feeding. Future research must determine the exact pathways linking gut nutrient administration to dopamine efflux. Current evidence points to parallel contributions by pre- and post-absorptive pathways, indicating that dopamine systems constitute a site of convergence through which distinct physiological signals can exert control over ingestive behaviors.

Animals, including humans, can achieve precise regulation of caloric intake by adjusting consumption in response to covert changes in energy density. It remains unknown, however, whether the presence of flavour cues are required for the ability to maintain constant caloric intake. Also unknown are the brain circuits that may function as the central calorie monitors that control adaptive adjustments in energy intake. Here we show that mice trained to lick a dry spout in order to receive intra-gastric infusions of a fat emulsion maintained constant hourly caloric intake by adjusting the number of dry licks in response to changes in caloric density. Animals also increased dry licking according to hunger levels, and developed conditioned preferences for dry sippers associated with high calorie infusions. Importantly, striatal dopamine levels were closely associated with the amount of calories ingested, rather than with the number of dry licks produced. Dopamine levels in dorsal and ventral striatum also reflected caloric density in mice passively receiving intra-gastric infusions of fat emulsions. Consistent with the above, systemic administration of the dopamine receptor blocker haloperidol markedly increased the production of dry licks needed to obtain high-calorie infusions, as if the caloric density of the infusions had been diluted. Conversely, haloperidol markedly decreased the production of dry licks needed to obtain low-calorie infusions. Taken together, our results support the proposition that brain dopamine circuits function as one central sensor of calorie ingestion, since (1) extracellular striatal dopamine levels fluctuate in proportion to the caloric density of nutrients infused in the gut; and (2) inhibiting dopamine receptor signalling disrupts the animals' ability to maintain constant caloric intake across experimental sessions.

Sugar exerts its potent reinforcing effects via both gustatory and post-ingestive pathways. It is, however, unknown whether sweetness and nutritional signals engage segregated brain networks to motivate ingestion. We found in mice that separate basal ganglia circuitries mediated the hedonic and nutritional actions of sugar. During sugar intake, suppressing hedonic value inhibited dopamine release in ventral, but not dorsal, striatum, whereas suppressing nutritional value inhibited dopamine release in dorsal, but not ventral, striatum. Consistently, cell-specific ablation of dopamine-excitable cells in dorsal, but not ventral, striatum inhibited sugar's ability to drive the ingestion of unpalatable solutions. Conversely, optogenetic stimulation of dopamine-excitable cells in dorsal, but not ventral, striatum substituted for sugar in its ability to drive the ingestion of unpalatable solutions. Our data indicate that sugar recruits a distributed dopamine-excitable striatal circuitry that acts to prioritize energy-seeking over taste quality.

El fútbol sala es una de las modalidades de este deporte que mas arraigo tiene hoy en día a nivel mundial, es un juego mucho mas rápido y estratégico donde las situaciones se dan a gran velocidad de pensamiento, por lo que la preparación que deben tener los jugadores debe ser la mas completa posible este trabajo se aborda de manera profunda la situación existente con las acciones de ataque rápido que se dieron en los partidos eliminatorios al campeonato del mundo con la selección de mayores de Cuba, para ello utilizamos los métodos científicos para poder llegar a definir nuestro problema como los métodos teóricos : análisis y síntesis, inductivo deductivo, análisis documental, histórico -lógico, entre los empíricos utilizamos: la observación y la encuesta y el criterio de especialistas, estos arrojaron resultados que nos permitieron avanzar en la investigación como poder determinar las causas de la in efectividad o mala ejecución de los contraataques así como la encuesta nos ayudo a tener la valoración de los entrenadores acerca de este mismo problema así como la opinión sobre los ejercicios que se esperan implementar. Por lo que nuestro objetivo es: Diseñar un conjunto de ejercicios quecontribuyan al mejoramiento de los contraataques por parte de los jugadores de La Selección Nacional de Futsala

In mesophiles, triosephosphate isomerase (TIM) is an obligated homodimer. We have previously shown that monomeric folding intermediates are common in the chemical unfolding of TIM, where dissociation provides 75% of the overall conformational stability of the dimer. However, analysis of the crystallographic structure shows that, during unfolding, intermonomeric contacts contribute to only 5% of the overall increase in accessible surface area. In this work several methodologies were used to characterize the thermal dissociation and unfolding of the TIM from Entamoeba histolytica (EhTIM) and a monomeric variant obtained by chemical derivatization (mEhTIM). During EhTIM unfolding, sequential transitions corresponding to dimer dissociation into a compact monomeric intermediate followed by unfolding and further aggregation of the intermediate occurred. In the case of mEhTIM, a single transition, analogous to the second transition of EhTIM, was observed. Calorimetric, spectroscopic, hydrodynamic, and functional evidence shows that dimer dissociation is not restricted to localized interface reorganization. Dissociation represents 55% (DeltaH(Diss) = 146.8 kcal mol(-1)) of the total enthalpy change (DeltaH(Tot) = 266 kcal mol(-1)), indicating that this process is linked to substantial unfolding. We propose that, rather than a rigid body process, subunit assembly is best represented by a fly-casting mechanism. In TIM, catalysis is restricted to the dimer; therefore, the interface can be viewed as the final nucleation motif that directs assembly, folding, and function.

Food as Reward Why does ice cream taste so good? High-fat foods activate a reward circuit in the brain involving dopamine, a neurotransmitter that regulates pleasure. Overconsumption of high-fat foods is thought to dampen this dopamine-induced reward sensation, leading to compensatory consumption of even more high-fat foods. The mechanisms by which dietary fat in the gut “talks” to the dopamine reward circuit are unclear. Tellez et al. (p. 800 ) suggest that an intestinal lipid messenger called oleoylethanolamine (OEA) may play a role—at least in mice. Mice on a high-fat diet had unusually low levels of intestinal OEA and exhibited deficient dopaminergic responses to gut stimulation with high-fat lipids. Infusion of OEA into these mice restored the dopaminergic response, and mice that had been accustomed to a high-fat diet began to eat more low-fat foods.

Exposure to a novel taste solution in the rat is followed by a decrease in its intake known as neophobia. This effect gradually disappears, and consumption increases from the second presentation of the taste (attenuation of neophobia), reflecting that the animal learned that it is safe to drink it. Conversely, if gastric malaise is induced after first intake, the rat will develop a long-lasting aversion (conditioned taste aversion). Previous attempts to elucidate the physiological nature of taste memory trace stems only from procedures that require malaise to measure taste memory. Here we assess the relevance of both muscarinic and N-methyl-d-aspartate receptors, known to be involved in conditioned taste aversion, on taste memory using a nonaversive procedure (attenuation of neophobia learning). Attenuation of neophobia was impaired by the muscarinic receptor antagonist, scopolamine, microinjected 20 min before, immediately after or up to 2 h after the first taste experience, suggesting that muscarinic receptors are involved in the acquisition and consolidation of attenuation of neophobia learning. However, the N-methyl-d-aspartate receptor antagonist, d,l-2-amino-5-phosphonovaleric acid, did not affect attenuation of neophobia even when the same dose of the drug was able to disrupt conditioned taste aversion learning, which suggests that attenuation of neophobia learning would be independent of N-methyl-d-aspartate receptors activity in the insular cortex. The neophobic response induced by strong saccharin presentation was not affected by either of the treatments given, which rules out any impairment in taste perception. These results indicate that while cortical muscarinic receptors are important in the formation and consolidation of safe memory trace, N-methyl-d-aspartate receptor activity appears to be noncritical.

It is not known whether behaviors unrelated to feeding are affected by hypothalamic regulators of hunger. We found that impairment of Agouti-related protein (AgRP) circuitry by either Sirt1 knockdown in AgRP-expressing neurons or early postnatal ablation of these neurons increased exploratory behavior and enhanced responses to cocaine. In AgRP circuit-impaired mice, ventral tegmental dopamine neurons exhibited enhanced spike timing-dependent long-term potentiation, altered amplitude of miniature postsynaptic currents and elevated dopamine in basal forebrain. Thus, AgRP neurons determine the set point of the reward circuitry and associated behaviors.

"El Comite Asesor de las Pautas de Actividad Fisica de 2018 busco sistematicamente las revisiones de la literatura existente para evaluar la relacion entre el entrenamiento en intervalos de alta intensidad (HIIT), el entrenamiento continuo de intensidad moderada (MICT) o el entrenamiento de resistencia (RT) y la reduccion del riesgo de enfermedad cardiometabolica. En este contexto, el objetivo del presente estudio fue investigar si 12 semanas de HIIT, RT, entrenamiento combinado (CT = HIIT + RT) o un plan NG indujeron una mejora en los factores de riesgo del sindrome metabolico, la funcion vascular y la aptitud fisica en sedentarios y sobrepeso y comparar las respuestas entre los cuatro grupos de intervencion. METODOS: El estudio incluyo un total de 57 sujetos sedentarios con obesidad abdominal o sobrepeso. Diseno paralelo aleatorio de doce semanas que examina los efectos de diferentes regimenes de ejercicio y / o GN en la composicion antropometrica y corporal (masa grasa y magra en todo el cuerpo, grasa del tronco, indice de masa grasa, masa muscular apendicular y circunferencia de la cintura); factores de riesgo del sindrome metabolico y parametros vasculares (lipidos en sangre, glucosa en ayunas, presion arterial, vasodilatacion mediada por flujo [FMD%], velocidad de la onda de pulso aortica (VOP) e indice de aumento [AIx]); y aptitud fisica (aptitud cardiorrespiratoria y fuerza de agarre). RESULTADOS: Los modelos lineales mixtos ajustados revelaron una mejora significativa en la aptitud cardiorrespiratoria (ml · kg · min -1 ): HIIT +8,3, RT +4,1 y CT +6,3 (todos P

Superior predatory skills led to the evolutionary triumph of jawed vertebrates. However, the mechanisms by which the vertebrate brain controls predation remain largely unknown. Here, we reveal a critical role for the central nucleus of the amygdala in predatory hunting. Both optogenetic and chemogenetic stimulation of central amygdala of mice elicited predatory-like attacks upon both insect and artificial prey. Coordinated control of cervical and mandibular musculatures, which is necessary for accurately positioning lethal bites on prey, was mediated by a central amygdala projection to the reticular formation in the brainstem. In contrast, prey pursuit was mediated by projections to the midbrain periaqueductal gray matter. Targeted lesions to these two pathways separately disrupted biting attacks upon prey versus the initiation of prey pursuit. Our findings delineate a neural network that integrates distinct behavioral modules and suggest that central amygdala neurons instruct predatory hunting across jawed vertebrates.

The rational designing of binding abilities in proteins requires an understanding of the relationship between structure and thermodynamics. However, our knowledge of the molecular origin of high-affinity binding of ligands to proteins is still limited; such is the case for l-lysine-l-arginine-l-ornithine periplasmic binding protein (LAOBP), a periplasmic binding protein from Salmonella typhimurium that binds to l-arginine, l-lysine, and l-ornithine with nanomolar affinity and to l-histidine with micromolar affinity. Structural studies indicate that ligand binding induces a large conformational change in LAOBP. In this work, we studied the thermodynamics of l-histidine and l-arginine binding to LAOBP by isothermal titration calorimetry. For both ligands, the affinity is enthalpically driven, with a binding ΔCp of ~-300 cal mol(-1) K(-1) , most of which arises from the burial of protein nonpolar surfaces that accompanies the conformational change. Osmotic stress measurements revealed that several water molecules become sequestered upon complex formation. In addition, LAOBP prefers positively charged ligands in their side chain. An energetic analysis shows that the protein acquires a thermodynamically equivalent state with both ligands. The 1000-fold higher affinity of LAOBP for l-arginine as compared with l-histidine is mainly of enthalpic origin and can be ascribed to the formation of an extra pair of hydrogen bonds. Periplasmic binding proteins have evolved diverse energetic strategies for ligand recognition. STM4351, another arginine binding protein from Salmonella, shows an entropy-driven micromolar affinity toward l-arginine. In contrast, our data show that LAOBP achieves nanomolar affinity for the same ligand through enthalpy optimization.

It is well established that animals including humans attribute greater reinforcing value to glucose-containing sugars compared to their non-caloric counterparts, generally termed ‘artificial sweeteners’. However, much remains to be determined regarding the physiological signals and brain systems mediating the attribution of greater reinforcing value to sweet solutions that contain glucose. Here we show that disruption of glucose utilization in mice produces an enduring inhibitory effect on artificial sweetener intake, an effect that did not depend on sweetness perception or aversion. Indeed, such an effect was not observed in mice presented with a less palatable, yet caloric, glucose solution. Consistently, hungry mice shifted their preferences away from artificial sweeteners and in favour of glucose after experiencing glucose in a hungry state. Glucose intake was found to produce significantly greater levels of dopamine efflux compared to artificial sweetener in dorsal striatum, whereas disrupting glucose oxidation suppressed dorsal striatum dopamine efflux. Conversely, inhibiting striatal dopamine receptor signalling during glucose intake in sweet-naïve animals resulted in reduced, artificial sweetener-like intake of glucose during subsequent gluco-deprivation. Our results demonstrate that glucose oxidation controls intake levels of sweet tastants by modulating extracellular dopamine levels in dorsal striatum, and suggest that glucose utilization is one critical physiological signal involved in the control of goal-directed sweetener intake.

Background Mounting evidence suggests that overeating may be conceptualized within the same behavioral and neurobiological framework as drug addiction. One potentially important difference between overeating versus drug abuse refers to the sensory stimulation of oral receptors by palatable foods, a feature that may be required for reinforcement during intake. Likewise, postingestive effects and caloric content of food also contribute to reinforcing behavior and might influence the development of compulsive eating behavior. The purpose of the current study was to establish whether intragastric self-administration of fat emulsions, that is, bypassing the oral cavity, recapitulates some of the behavioral and neurobiological hallmarks of psychostimulant self-administration. Methods We used behavioral assays in mice to assess acquisition, maintenance, extinction, and reinstatement of intragastric self-administration of lipid emulsions to determine the extent to which postoral fat self-administration recapitulates psychostimulant self-administration. Striatal dopamine efflux during behavioral tasks was determined by brain microdialysis coupled to chromatographic-electrochemical analyses. Results We show that in direct analogy to drug self-administration, 1) decreases in fat dose concentration were met with compensatory increases in response rates aimed at maintaining constant hourly caloric intake; 2) rates of responding markedly increased during both extinction and progressive ratio schedules of reinforcement; and 3) elevations in striatal dopamine levels observed during maintenance were markedly attenuated during extinction sessions, only to be restored on reinstatement. Conclusions Our data thus support the contention that stimulation of oral receptors by caloric foods may not be required for the expression of certain addiction-related neurobehavioral markers.

Neurons in the nucleus accumbens (NAc) have been shown to participate in several behavioral states, including feeding and sleep. However, it is not known if the same neuron participates in both states and, if so, how similar are the responses. In addition, since the NAc contains several cell types, it is not known if each type participates in the transitions associated with feeding and sleep. Such knowledge is important for understanding the interaction between two different neural networks. For these reasons we recorded ensembles of NAc neurons while individual rats volitionally transitioned between the following states: awake and goal directed, feeding, quiet-awake, and sleeping. We found that during both feeding and sleep states, the same neurons could increase their activity (be activated) or decrease their activity (be inactivated) by feeding and/or during sleep, thus indicating that the vast majority of NAc neurons integrate sleep and feeding signals arising from spatially distinct neural networks. In contrast, a smaller population was modulated by only one of the states. For the majority of neurons in either state, we found that when one population was excited, the other was inhibited, suggesting that they act as a local circuit. Classification of neurons into putative interneurons [fast-spiking interneurons (pFSI) and choline acetyltransferase interneurons (pChAT)] and projection medium spiny neurons (pMSN) showed that all three types are modulated by transitions to and from feeding and sleep states. These results show, for the first time, that in the NAc, those putative inhibitory interneurons respond similarly to pMSN projection neurons and demonstrate interactions between NAc networks involved in sleep and feeding.

1 páginas A sixteen year old famale patient consulted whit 1 month of severe dry cough, hemoptysis, pleuritic chest pain and effort dyspnea.

Proteins encoded by the gene segment 6a of the lambda variable light-chain repertoire are strongly associated with amyloid deposition. 6aJL2 is a model protein constructed with the predicted sequences encoded by the 6a and JL2 germ line genes. In this work, we characterized the urea- and temperature-induced unfolding of 6aJL2. In the short time scale, spectroscopic, hydrodynamic and calorimetric experiments were compatible with a two-state transition. Furthermore, DeltaG, m and the midpoint urea concentration obtained from equilibrium experiments were compatible with those obtained from kinetic experiments. Since fibril formation is a slow process, samples were also incubated for longer times. After incubation for several hours at 37 degrees C, spectroscopic, hydrodynamic and calorimetric experiments revealed the presence of a partially unfolded off-pathway intermediate around the midpoint urea concentration (1.5-3.0 M urea). In vitro fibrillogenesis assays show that the maximum growth rate for fibril formation and the minimum lag time were obtained at urea concentrations where the partially unfolded state was populated (2.5 M urea at 37 degrees C). This indicates that this partially unfolded state is critical for in vitro fibril formation. Concentration-dependent kinetics and hydrodynamic properties of the intermediate were consistent with a soluble oligomeric state. The intermediate is formed around the midpoint urea concentration, where the native and unfolded states are equally populated and their rate of interconversion is the slowest. This situation may promote the slow accumulation of an intermediate state that is prone to aggregate.

Seven 2-amino-4-aryl-1,3-thiazoles (1a–g) and their corresponding 2-aminoacetyl (2a–g) and 2-aminoacetyl-5-bromo (3a–g) derivatives were synthesized and tested in vitro against 11 reference strains, three Gram-positive and four Gram-negative bacteria, two yeasts, and two moulds. Toxicity of the compounds was also evaluated using the brine shrimp test. Compounds 1a, 1b, 1e–g, and 3b showed moderate antimicrobial activity at different concentrations. The results indicated that acetylation of the amino group and bromination at position 5 of the thiazole moiety cause lost of activity. Compounds 1a, 1e, and 1f showed toxicity to brine shrimp nauplii below 10 ppm. Most other compounds showed moderate toxicity, LD50 above 100 ppm. Structures of all compounds were confirmed by NMR and MS data. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:254–260, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20182

Abstract Poor slurry density control in cementing operations leads to a failure to reproduce laboratory designs at the field level. Adverse consequences include poor bonding, incomplete fill-up, inefficiency of cementing additives, lower compressive strength, erroneous thickening time, and possible inability to control formation pressures. In three locations worldwide, field testing of a new closed-loop control slurry mixer has demonstrated that density control can be achieved while mixing and pumping direct to the well. There is no need for batch-mixing facilities, because the entire slurry is pumped at the correct density. The test installations, types of jobs and slurries pumped during the first 12 months, and the parameters recorded to measure the effectiveness of the mixer are discussed in this paper. The results and conclusions demonstrate that the mixer can automatically control density during mixing within 0.1 lb/gal. Other results include improved field slurry rheology, capacity to mix conventionally problematic slurries. and shorter operational time. INTRODUCTION The mixer was evolved in response to the growing need to reproduce laboratory-quality cement slurries in field operations. It is widely accepted that maintaining the cement slurry density at its design specification during a cement job is a prominent field problem. Density recordings often show a variance of ±0.5 to 1 lb/gal, especially during the early part of the job, while changing the rate. and followed by a changeover from a low-density lead slurry to the higher density tail. Density variations during a cement job affect the mix-water-to-solids ratio. Dry cement additives are generally given by weight of cement. In the case of liquid additives predisso1ved in water, their concentration will vary as a function of the mixed density. When additives are dry blended, their concentration by weight of cement will be unaffected by slurry density fluctuations. Previous work1 showed that density error has always had a dramatic effect on all major slurry properties. To obtain dry blends which are perfectly homogeneous is very difficult. thereby intensifying the problems associated with density variations. In other words, whether using dry or liquid additives, poor density control while mixing will affect all major slurry properties and ultimately lead to unpredictable slurry performance. Current Solutions When discussing slurry density, it is important to state the limits of field equipment used to measure it. If properly handled and calibrated, use of pressurized mud balances and densitometers improves this measurement; however, there exists a range of ±0.1 1b/gal within which the absolute accuracy of the density measurement cannot be guaranteed. Since this is considered the accuracy limit of the devices, it therefore follows that with contemporary technology ±0.1 lb/gal will be the accuracy limit for density control.