Efectos de los compuestos fenólicos del aceite de oliva virgen en la salud: ¿evidencia sólida o simplemente otro fiasco?

Current research suggests that virgin olive oil (VOO) phenolics are potent preventive and therapeutic agents against metabolic diseases associated with inflammation and oxidative stress. Evidence-based medicine requires these effects be proved in randomized controlled trials (RCT), which are then assessed in meta-analyses, to ensure that the alleged health benefits really proceed in humans. The available evidence is limited to the ability of VOO phenolic compounds to protect lipoproteins from oxidation and to reduce systolic pressure in hypertensive individuals. No RCT assessing the effects of VOO phenolics on diabetes and neurodegenerative diseases have been performed, and those focused on osteoarthritis and cancer provided very scarce information. Therefore, RCT in extensive and diverse population groups, with different disorders and phenolic doses adjusted to usual VOO consumptions are necessary to achieve high quality scientific evidence before nutritional recommendations can be given to the general public.Las investigaciones actuales indican que los compuestos fenólicos del aceite de oliva virgen (AOV) son potentes agentes preventivos y terapéuticos contra las enfermedades metabólicas asociadas con la inflamación y el estrés oxidativo. La medicina basada en la evidencia requiere que estos efectos se prueben en ensayos aleatorizados controlados (RCT), que son después evaluados en meta-análisis, para garantizar que los supuestos beneficios para la salud realmente se registran en humanos. La evidencia disponible se limita a la capacidad de los compuestos fenólicos del AOV para proteger las lipoproteínas de la oxidación y reducir la presión sistólica en individuos hipertensos. No se han realizado RCT que evalúen el efecto de estos compuestos sobre la diabetes y las enfermedades neurodegenerativas, y los que se centraron en la osteoartritis y el cáncer han proporcionado información muy escasa. Por lo tanto, nuevos RCT, en grupos de población extensos y diversos, con diferentes patologías y con dosis de fenoles ajustadas a los consumos habituales de AOV, deben desarrollarse, para lograr evidencia científica de alta calidad antes de que se puedan dar recomendaciones nutricionales al público en general

Obesity, metabolic syndrome and diabetes: cardiovascular implications and therapy

Obesity, metabolic syndrome, and type-2 diabetes mellitus are 3 interrelated conditions that share a number of pathophysiological mechanisms and that are frequently observed to lead, in succession, to cardiovascular complications. The fact that their prevalence is increasing alarmingly should prompt all healthcare professionals urgently to implement measures to prevent these complications. The most effective, though also the least adopted, are those related to lifestyle modification. Drug treatment targeted at controlling risk factors (eg, hypertension, dyslipidemia, and thrombophilia), metabolic abnormalities, and excess weight is also necessary

Mean-field analysis of the q-voter model on networks

We present a detailed investigation of the behavior of the nonlinear q-voter model for opinion dynamics. At the mean-field level we derive analytically, for any value of the number q of agents involved in the elementary update, the phase diagram, the exit probability and the consensus time at the transition point. The mean-field formalism is extended to the case that the interaction pattern is given by generic heterogeneous networks. We finally discuss the case of random regular networks and compare analytical results with simulations.Comment: 20 pages, 10 figure

Renormalization group study of one-dimensional systems with roughening transitions

A recently introduced real space renormalization group technique, developed for the analysis of processes in the Kardar-Parisi-Zhang universality class, is generalized and tested by applying it to a different family of surface growth processes. In particular, we consider a growth model exhibiting a rich phenomenology even in one dimension. It has four different phases and a directed percolation related roughening transition. The renormalization method reproduces extremely well all the phase diagram, the roughness exponents in all the phases and the separatrix among them. This proves the versatility of the method and elucidates interesting physical mechanisms.Comment: Submitted to Phys. Rev.

Global culture: A noise induced transition in finite systems

We analyze the effect of cultural drift, modeled as noise, in Axelrod's model for the dissemination of culture. The disordered multicultural configurations are found to be metastable. This general result is proven rigorously in d=1, where the dynamics is described in terms of a Lyapunov potential. In d=2, the dynamics is governed by the average relaxation time T of perturbations. Noise at a rate r 1/T sustains disorder. In the thermodynamic limit, the relaxation time diverges and global polarization persists in spite of a dynamics of local convergence.Comment: 4 pages, 5 figures. For related material visit http://www.imedea.uib.es/physdept

Studying nonlinear effects on the early stage of phase ordering using a decomposition method

Nonlinear effects on the early stage of phase ordering are studied using Adomian's decomposition method for the Ginzburg-Landau equation for a nonconserved order parameter. While the long-time regime and the linear behavior at short times of the theory are well understood, the onset of nonlinearities at short times and the breaking of the linear theory at different length scales are less understood. In the Adomian's decomposition method, the solution is systematically calculated in the form of a polynomial expansion for the order parameter, with a time dependence given as a series expansion. The method is very accurate for short times, which allows to incorporate the short-time dynamics of the nonlinear terms in a analytical and controllable way.Comment: 11 pages, 1 figure, to appear in Phys Lett

Association of increased plasma cardiotrophin-1 with inappropriate left ventricular mass in essential hypertension

Inappropriate left ventricular mass is present when the value of left ventricular mass exceeds individual needs to compensate hemodynamic load imposed by increased blood pressure. The goal of this study was to investigate whether plasma concentration of cardiotrophin-1, a cytokine that induces exaggerated hypertrophy in cardiomyocytes with hypertensive phenotype, is related to inappropriate left ventricular mass in patients with essential hypertension. The study was performed in 118 patients with never-treated hypertension and without prevalent cardiac disease. The left ventricular mass prediction from stroke work (systolic blood pressurexDoppler stroke volume), sex, and height (in meters(2.7)) was derived. An observed left ventricular mass/predicted left ventricular mass value >128% defined inappropriate left ventricular mass. Plasma cardiotrophin-1 was measured by an enzyme-linked immunosorbent assay. The studies were repeated in a group of 45 patients after 1 year of antihypertensive treatment. At baseline 67 and 51 patients presented with appropriate and inappropriate left ventricular mass, respectively. Plasma cardiotrophin-1 was higher (P<0.001) in patients with inappropriate mass than in patients with appropriate mass and normotensive controls. A direct correlation was found between cardiotrophin-1 and observed left ventricular mass/predicted left ventricular mass ratio (r=0.330, P<0.001) in all hypertensive patients. After treatment, plasma cardiotrophin-1 decreased and increased in patients in which inappropriate left ventricular mass regressed and persisted, respectively, despite a similar reduction of blood pressure in the 2 subgroups of patients. Albeit descriptive in nature, these results suggest the hypothesis that an excess of cardiotrophin-1 may contribute to inappropriate left ventricular growth in hypertensive patients

Nonequilibrium phase transition in a model for the propagation of innovations among economic agents

We characterize the different morphological phases that occur in a simple one-dimensional model of propagation of innovations among economic agents [X.\ Guardiola, {\it et. al.}, Phys. Rev E {\bf 66}, 026121 (2002)]. We show that the model can be regarded as a nonequilibrium surface growth model. This allows us to demonstrate the presence of a continuous roughening transition between a flat (system size independent fluctuations) and a rough phase (system size dependent fluctuations). Finite-size scaling studies at the transition strongly suggest that the dynamic critical transition does not belong to directed percolation and, in fact, critical exponents do not seem to fit in any of the known universality classes of nonequilibrium phase transitions. Finally, we present an explanation for the occurrence of the roughening transition and argue that avalanche driven dynamics is responsible for the novel critical behavior

Activation of microglia in specific hypothalamic nuclei and the cerebellum of adult rats exposed to neonatal overnutrition

Much attention has been drawn to the possible involvement of hypothalamic inflammation in the pathogenesis of metabolic disorders, especially in response to a high-fat diet. Microglia, the macrophages of the central nervous system, can be activated by proinflammatory signals resulting in the local production of specific interleukins and cytokines, which in turn could exacerbate the pathogenic process. Because obesity itself is considered to be a state of chronic inflammation, we evaluated whether being overweight results in microglial activation in the hypothalamus of rats on a normal diet. Accordingly, we used a model of neonatal overnutrition that entailed adjustment of litter size at birth (small litters: four pups/dam versus normal litters: 12 pups/dam) and resulted in a 15% increase in bodyweight and increased circulating leptin levels at postnatal day 60. Rats that were overnourished during neonatal life had an increased number of activated microglia in specific hypothalamic areas such as the ventromedial hypothalamus, which is an important site for metabolic control. However, this effect was not confined to the hypothalamus because significant microglial activation was also observed in the cerebellar white matter. There was no change in circulating tumour necrosis factor (TNF) α levels or TNFα mRNA levels in either the hypothalamus or cerebellum. Interleukin (IL)6 protein levels were higher in both the hypothalamus and cerebellum, with no change in IL6 mRNA levels. Because circulating IL6 levels were elevated, this rise in central IL6 could be a result of increased uptake. Thus, activation of microglia occurs in adult rats exposed to neonatal overnutrition and a moderate increase in weight gain on a normal diet, possibly representing a secondary response to systemic inflammation. Moreover, this activation could result in local changes in specific hypothalamic nuclei that in turn further deregulate metabolic homeostasi

The impact of genetic adaptation on chimpanzee subspecies differentiation

Published: November 25, 2019Chimpanzees, humans' closest relatives, are in danger of extinction. Aside from direct human impacts such as hunting and habitat destruction, a key threat is transmissible disease. As humans continue to encroach upon their habitats, which shrink in size and grow in density, the risk of inter-population and cross-species viral transmission increases, a point dramatically made in the reverse with the global HIV/AIDS pandemic. Inhabiting central Africa, the four subspecies of chimpanzees differ in demographic history and geographical range, and are likely differentially adapted to their particular local environments. To quantitatively explore s genetic adaptation, we investigated the genic enrichment for SNPs highly differentiated between chimpanzee subspecies. Previous analyses of such patterns in human populations exhibited limited evidence of adaptation. In contrast, chimpanzees show evidence of recent positive selection, with differences among subspecies. Specifically, we observe strong evidence of recent selection in eastern chimpanzees, with highly differentiated SNPs being uniquely enriched in genic sites in a way that is expected under recent adaptation but not under neutral evolution or background selection. These sites are enriched for genes involved in immune responses to pathogens, and for genes inferred to differentiate the immune response to infection by simian immunodeficiency virus (SIV) in natural vs. non-natural host species. Conversely, central chimpanzees exhibit an enrichment of signatures of positive selection only at cytokine receptors, due to selective sweeps in CCR3, CCR9 and CXCR6 -paralogs of CCR5 and CXCR4, the two major receptors utilized by HIV to enter human cells. Thus, our results suggest that positive selection has contributed to the genetic and phenotypic differentiation of chimpanzee subspecies, and that viruses likely play a predominate role in this differentiation, with SIV being a likely selective agent. Interestingly, our results suggest that SIV has elicited distinctive adaptive responses in these two chimpanzee subspecies.Joshua M. Schmidt, Marc de Manuel, Tomas Marques-Bonet, Sergi Castellano, Aida M. André