If players are sparse social dilemmas are too: Importance of percolation for evolution of cooperation

Spatial reciprocity is a well known tour de force of cooperation promotion. A thorough understanding of the effects of different population densities is therefore crucial. Here we study the evolution of cooperation in social dilemmas on different interaction graphs with a certain fraction of vacant nodes. We find that sparsity may favor the resolution of social dilemmas, especially if the population density is close to the percolation threshold of the underlying graph. Regardless of the type of the governing social dilemma as well as particularities of the interaction graph, we show that under pairwise imitation the percolation threshold is a universal indicator of how dense the occupancy ought to be for cooperation to be optimally promoted. We also demonstrate that myopic updating, due to the lack of efficient spread of information via imitation, renders the reported mechanism dysfunctional, which in turn further strengthens its foundations.Comment: 6 two-column pages, 5 figures; accepted for publication in Scientific Reports [related work available at http://arxiv.org/abs/1205.0541

Errores de medicación en niños que acuden a los servicios de urgencias pediátricas

Errores de medicación; Servicios de urgencias; PediatríaMedication errors; Emergency departments; PediatricsErrors de medicació; Servei d'urgències; PediatriaObjectives: Medication safety represents an important challenge in children. There are limited studies on medication errors in pediatric patients visiting emergency departments. To help bridge this gap, we characterized the medication errors detected in these patients, determining their severity, the stages of the medication process in which they occurred, the drugs involved, and the types and causes associated with the errors. Methods: We conducted a multicenter prospective observational study in the pediatric emergency departments of 8 Spanish public hospitals over a 4-month period. Medication errors detected by emergency pediatricians in patients between 0 and 16 years of age were evaluated by a clinical pharmacist and a pediatrician. Each medication error was analyzed according to the updated Spanish Taxonomy of Medication Errors. Results: In 99,797 visits to pediatric emergency departments, 218 (0.2%) medication errors were detected, of which 74 (33.9%) resulted in harm (adverse drug events). Preschoolers were the age group with the most medication errors (126/218). Errors originated mainly in the prescribing stage (66.1%), and also by self-medication (16.5%) and due to wrong administration of the medication by family members (15.6%). Dosing errors (51.4%) and wrong/improper drugs (46.8%) were the most frequent error types. Anti-infective drugs (63.5%) were the most common drugs implicated in medication errors with harm. Underlying causes associated with a higher proportion of medication errors were "medication knowledge deficit" (63.8%), "deviation from procedures/guidelines" (48.6%) and "lack of patient information" (30.3%). Conclusions: Medication errors presented by children attending emergency departments arise from prescriptions, self-medicationand administration, and lead to patient harm in one third of cases. Developing effective interventions based on the types of errors and the underlying causes identified will improve patient safety.Objetivos La seguridad de medicamentos en pediatría supone un verdadero reto. Se dispone de escasos estudios que hayan analizado los errores de medicación en los pacientes pediátricos que acuden a los servicios de urgencias. El objetivo de este estudio ha sido caracterizar los errores detectados en estos pacientes, determinando su severidad, los procesos afectados, los medicamentos implicados, y los tipos de errores y causas asociados. Métodos Estudio multicéntrico observacional prospectivo realizado en los servicios de urgencias de 8 hospitales públicos españoles durante 4 meses. Los errores de medicación detectados por los pediatras de urgencias en pacientes entre 0 y 16 años fueron evaluados por un farmacéutico y un pediatra. Los errores de medicación fueron analizados utilizando la Taxonomía Española de Errores de Medicación actualizada. Resultados En 99.797 visitas a urgencias se detectaron 218 (0,2%) errores de medicación, de los cuales 74 (33,9%) causaron daños (eventos adversos por medicamentos). Los preescolares fueron el grupo poblacional con mayor número de errores de medicación (126/218). Los errores se originaron mayoritariamente en la prescripción (66,1%), por automedicación (16,5%) y por administración equivocada por parte de familiares (15,6%). Los tipos de errores más frecuentes fueron “dosis incorrectas” (51,4%) y “medicamento inapropiado” (46,8%). Los antiinfecciosos (63,5%) fueron los fármacos más comúnmente implicados en los errores con daño. Las causas subyacentes asociadas a una mayor proporción de errores de medicación fueron: “falta de conocimiento del medicamento” (63,8%), “falta de seguimiento de los procedimientos” (48,6%) y “falta de información del paciente” (30,3%). Conclusiones Los errores de medicación en la población pediátrica que acude a urgencias se producen en la prescripción, por automedicación y en la administración, provocando daños a los pacientes en un tercio de las ocasiones. Desarrollar prácticas seguras basadas en los tipos de errores detectados y sus causas subyacentes, mejorará la seguridad de los pacientes.This study has been carried out with the support of a grant provided by the Spanish Society of Hospital Pharmacists for the period 2015–2016

La Captación de radicales libres y la inhibición de α-glucosidasa, dos posibles mecanismos involucrados en la actividad antidiabética del ácido oleanólico

This work investigates the role of oleanolic acid (OA), isolated from the olive (Olea europaea L.) leaf, as a radical scavenger and inhibitor of the hydrolyzing enzymes of dietary carbohydrates. New evidence is provided showing that OA may capture 2,2’-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) and peroxyl radicals, and also exert a strong and non -competitive inhibition of α-glucosidase (IC50 10.11 ± 0.30 μM). The kinetic and spectrometric analyses performed indicate that OA interacts with this enzyme inside a hydrophobic pocket, through an endothermic and non spontaneous process of a hydrophobic nature. These are two possible mechanisms by which OA may facilitate a better control of post-prandial hyperglycaemia and oxidative stress, so contributing to preserving insulin signalling. Obesity, insulin resistance and Type 2 Diabetes Mellitus are considered the first pandemics of the 21st century. In this sense, OA might be used in future preventive and therapeutic strategies, as an ingredient in new drugs and functional foods.Este trabajo estudia el papel del ácido oleanólico (OA), aislado de la hoja de olivo, como secuestrador de radicales libres e inhibidor de enzimas implicados en la hidrolisis de los carbohidratos de la dieta, dos mecanismos por los que el triterpeno podría mitigar la hiperglicemia postprandial y el estrés oxidativo. Se aportan nuevas evidencias que muestran que el OA puede capturar radicales ácido 2,2’-azino-bis-(3-etilbenzotiazolín)-6-sulfónico y peroxilo, y que ejerce una potente inhibición no-competitiva de α-glucosidasa (IC50 10.11±0.30 μM). El análisis cinético y espectrométrico llevado a cabo indica que OA interacciona con este enzima en el interior de un bolsillo hidrofóbico, mediante un proceso endotérmico no espontáneo, de naturaleza hidrofóbica. Estos son dos posibles mecanismos por los cuales el OA puede facilitar un mejor control de la hiperglucemia postprandial y el estrés oxidativo, lo que contribuye a preservar la señalización de la insulina. La obesidad, la resistencia a la insulina y la diabetes mellitus tipo 2 se consideran la primera pandemia del siglo XXI. En este sentido, el OA podría ser utilizado en futuras estrategias preventivas y terapéuticas, como ingrediente de nuevos fármacos y alimentos funcionales

Mesoscopic structure conditions the emergence of cooperation on social networks

We study the evolutionary Prisoner's Dilemma on two social networks obtained from actual relational data. We find very different cooperation levels on each of them that can not be easily understood in terms of global statistical properties of both networks. We claim that the result can be understood at the mesoscopic scale, by studying the community structure of the networks. We explain the dependence of the cooperation level on the temptation parameter in terms of the internal structure of the communities and their interconnections. We then test our results on community-structured, specifically designed artificial networks, finding perfect agreement with the observations in the real networks. Our results support the conclusion that studies of evolutionary games on model networks and their interpretation in terms of global properties may not be sufficient to study specific, real social systems. In addition, the community perspective may be helpful to interpret the origin and behavior of existing networks as well as to design structures that show resilient cooperative behavior.Comment: Largely improved version, includes an artificial network model that fully confirms the explanation of the results in terms of inter- and intra-community structur

Impact of Physical Exercise on Melanoma Hallmarks: Current Status of Preclinical and Clinical Research

In recent years, accumulating evidence from preclinical and clinical studies consistently indicated that physical activity/exercise plays a crucial role in reducing the incidence and recurrence of various malignancies, by exerting a beneficial modulation of cancer hallmarks. moreover, physical activity is suggested to attenuate certain adverse effects of anticancer therapy, including the reduction of cardiovascular toxicity and symptoms related to depression and anxiety, among others, while preserving muscular strength. In the case of melanoma, the relationship with physical activity has been critically debated. historically, several cohort studies and meta-analyses reported a positive association between physical activity/exercise and melanoma risk. this association was primarily attributed to outdoor activities that may expose the skin to UV radiation, a well-known risk factor for melanocyte transformation. However, more recent evidence does not support such association and recognizes physical activity/exercise role in both melanoma prevention and progression. nevertheless, sun protection is recommended during outdoor training to minimize UV radiation exposure. this narrative review summarizes preclinical and clinical data about physical activity effects on melanoma hallmarks. Specifically, experimental evidence is reported concerning (i) invasion and metastasis, (ii) reprogramming of energy metabolism, (iii) angiogenesis, (iv) resistance to cell death, (v) evasion from immune destruction, and (vi) tumor-promoting inflammation

Free radical scavenging and α-glucosidase inhibition, two potential mechanisms involved in the anti-diabetic activity of oleanolic acid

This work investigates the role of oleanolic acid (OA), isolated from the olive (<em>Olea europaea</em> L.) leaf, as a radical scavenger and inhibitor of the hydrolyzing enzymes of dietary carbohydrates. New evidence is provided showing that OA may capture 2,2’-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) and peroxyl radicals, and also exert a strong and non -competitive inhibition of α-glucosidase (IC₅₀ 10.11 ± 0.30 μM). The kinetic and spectrometric analyses performed indicate that OA interacts with this enzyme inside a hydrophobic pocket, through an endothermic and non spontaneous process of a hydrophobic nature. These are two possible mechanisms by which OA may facilitate a better control of post-prandial hyperglycaemia and oxidative stress, so contributing to preserving insulin signalling. Obesity, insulin resistance and Type 2 Diabetes Mellitus are considered the first pandemics of the 21st century. In this sense, OA might be used in future preventive and therapeutic strategies, as an ingredient in new drugs and functional foods.<br><br>Este trabajo estudia el papel del ácido oleanólico (OA), aislado de la hoja de olivo, como secuestrador de radicales libres e inhibidor de enzimas implicados en la hidrolisis de los carbohidratos de la dieta, dos mecanismos por los que el triterpeno podría mitigar la hiperglicemia postprandial y el estrés oxidativo. Se aportan nuevas evidencias que muestran que el OA puede capturar radicales ácido 2,2’-azino-bis-(3-etilbenzotiazolín)-6-sulfónico y peroxilo, y que ejerce una potente inhibición no-competitiva de α-glucosidasa (IC₅₀ 10.11±0.30 μM). El análisis cinético y espectrométrico llevado a cabo indica que OA interacciona con este enzima en el interior de un bolsillo hidrofóbico, mediante un proceso endotérmico no espontáneo, de naturaleza hidrofóbica. Estos son dos posibles mecanismos por los cuales el OA puede facilitar un mejor control de la hiperglucemia postprandial y el estrés oxidativo, lo que contribuye a preservar la señalización de la insulina. La obesidad, la resistencia a la insulina y la diabetes mellitus tipo 2 se consideran la primera pandemia del siglo XXI. En este sentido, el OA podría ser utilizado en futuras estrategias preventivas y terapéuticas, como ingrediente de nuevos fármacos y alimentos funcionales

PREVALENCE OF UNKNOWN DIABETES AND IMPAIRED GLUCOSE TOLERANCE IN PATIENTS WITH IMPAIRED FASTING GLUCOSE

There are many community-based studies on the prevalence of diabetes, impaired glucose tolerance (IGT) and impaired fasting glucose (IFG). However, studies on the prevalence of IGT and diabetes unknown in patients with IFG, by 75-g oral glucose tolerance test (OGTT), are few and small.CIBEROBN is an Instituto de Salud Carlos III initiative. This work has been co-financied by CIBEROBN, Research Grants of the Ministerio de Economía y Competitividad of Spain (Instituto de Salud Carlos III: PI10/00913), and Consejería de Salud de la Junta de Andalucía of Spain (PI-0037/2008 and PI-0112-2013).Peer Reviewe

Effects of dimers on cooperation in the spatial prisoner's dilemma game

We investigate the evolutionary prisoner's dilemma game in structured populations by introducing dimers, which are defined as that two players in each dimer always hold a same strategy. We find that influences of dimers on cooperation depend on the type of dimers and the population structure. For those dimers in which players interact with each other, the cooperation level increases with the number of dimers though the cooperation improvement level depends on the type of network structures. On the other hand, the dimers, in which there are not mutual interactions, will not do any good to the cooperation level in a single community, but interestingly, will improve the cooperation level in a population with two communities. We explore the relationship between dimers and self-interactions and find that the effects of dimers are similar to that of self-interactions. Also, we find that the dimers, which are established over two communities in a multi-community network, act as one type of interaction through which information between communities is communicated by the requirement that two players in a dimer hold a same strategy.Comment: 12 pages and 3 figure