Basic Study and Clinical Implications of Left Ventricular False Tendon. Is it Associated With Innocent Murmur in Children or Heart Disease?

Introducción y objetivos: El falso tendón del ventrículo izquierdo es una estructura descrita anatómicamente por Turner. Se desconoce su función dentro de la fisiología cardiaca. Se ha postulado, sin alcanzar consenso, su relación con diversas alteraciones eléctricas funcionales. El objetivo es conocer cuando aparece, su prevalencia, su composición histológica y su asociación con el soplo inocente infantil o con enfermedad cardiaca. Métodos: La investigación básica se realizó por la disección anatómica en cadáveres de corazones humanos adultos para describir el falso tendón y su histología. La investigación clínica se realizó en población pediátrica mediante ecocardiografía y se analizó su relación con cardiopatía, el soplo inocente infantil u otras alteraciones. Prenatalmente se realizaron ecocardiografías fetales a diferentes edades gestacionales. Resultados: La presencia del falso tendón es la norma en la disección cardiaca, y está constituido por fibras de tejido muscular y conectivo. En la población pediátrica, la presencia ecocardiografía del falso tendón fue del 83%, y solo mostró relación estadísticamente significativa con el soplo inocente infantil y una menor aceleración de la aorta. Por ecocardiografía fetal, se objetivó su presencia desde al menos la semana 20 de gestación . Conclusiones: El falso tendón del ventrículo izquierdo es una normalidad clínica visible por ecocardiografía fetal ya desde la semana 20, con presencia hasta la edad adulta sin relación con enfermedad, únicamente con la presencia de soplo inocente en edad pediátrica; queda por determinar si es la causa del soplo y si es su ausencia o anomalías estructurales lo que se relaciona con enfermedad.Introduction and objectives: Left ventricular false tendon is a structure of unknown function in cardiac physiology that was first described anatomically by Turner. This condition may be related to various electrical or functional abnormalities, but no consensus has ever been reached. The purpose of this study was to determine the time of appearance, prevalence and histologic composition of false tendon, as well as its association with innocent murmur in children and with heart disease. Methods: The basic research was performed by anatomic dissection of hearts from adult human cadavers to describe false tendon and its histology. The clinical research consisted of echocardiographic study in a pediatric population to identify any relationship with heart disease, innocent murmur in children, or other abnormalities. Fetal echocardiography was performed prenatally at different gestational ages. Results: False tendon was a normal finding in cardiac dissection and was composed of muscle and connective tissue fibers. In the pediatric population, false tendon was present in 83% on echocardiography and showed a statistically significant association only with innocent murmur in children and slower aortic acceleration. The presence of false tendon was first observed on fetal echocardiography from week 20 of pregnancy

Variable-based multi-module data caches for clustered VLIW processors

Memory structures consume an important fraction of the total processor energy. One solution to reduce the energy consumed by cache memories consists of reducing their supply voltage and/or increase their threshold voltage at an expense in access time. We propose to divide the L1 data cache into two cache modules for a clustered VLIW processor consisting of two clusters. Such division is done on a variable basis so that the address of a datum determines its location. Each cache module is assigned to a cluster and can be set up as a fast power-hungry module or as a slow power-aware module. We also present compiler techniques in order to distribute variables between the two cache modules and generate code accordingly. We have explored several cache configurations using the Mediabench suite and we have observed that the best distributed cache organization outperforms traditional cache organizations by 19%-31% in energy-delay and by 11%-29% in energy-delay. In addition, we also explore a reconfigurable distributed cache, where the cache can be reconfigured on a context switch. This reconfigurable scheme further outperforms the best previous distributed organization by 3%-4%.Peer ReviewedPostprint (published version

Recognition of fibrotic infarct density by the pattern of local systolic-diastolic myocardial electrical impedance

Myocardial electrical impedance is a biophysical property of the heart that is influenced by the intrinsic structural characteristics of the tissue. Therefore, the structural derangements elicited in a chronic myocardial infarction should cause specific changes in the local systolic-diastolic myocardial impedance, but this is not known. This study aimed to characterize the local changes of systolic-diastolic myocardial impedance in a healed myocardial infarction model. Six pigs were successfully submitted to 150 min of left anterior descending (LAD) coronary artery occlusion followed by reperfusion. 4 weeks later, myocardial impedance spectroscopy (1–1000 kHz) was measured at different infarction sites. The electrocardiogram, left ventricular (LV) pressure, LV dP/dt, and aortic blood flow (ABF) were also recorded. A total of 59 LV tissue samples were obtained and histopathological studies were performed to quantify the percentage of fibrosis. Samples were categorized as normal myocardium (50%). Resistivity of normal myocardium depicted phasic changes during the cardiac cycle and its amplitude markedly decreased in dense scar (18 ± 2 ·cm vs. 10 ± 1 ·cm, at 41 kHz; P < 0.001, respectively). The mean phasic resistivity decreased progressively from normal to heterogeneous and dense scar regions (285 ± 10 ·cm, 225 ± 25 ·cm, and 162 ± 6 ·cm, at 41 kHz; P < 0.001 respectively). Moreover, myocardial resistivity and phase angle correlated significantly with the degree of local fibrosis (resistivity: r = 0.86 at 1 kHz, P < 0.001; phase angle: r = 0.84 at 41 kHz, P < 0.001). Myocardial infarcted regions with greater fibrotic content show lower mean impedance values and more depressed systolic-diastolic dynamic impedance changes. In conclusion, this study reveals that differences in the degree of yocardial fibrosis can be detected in vivo by local measurement of phasic systolic-diastolic bioimpedance spectrum. Once this new bioimpedance method could be used via a catheter-based device, it would be of potential clinical applicability for the recognition of fibrotic tissue to guide the ablation of atrial or ventricular arrhythmias.Award-winningPostprint (published version

Effects of Sodium Chloride-Rich Mineral Water on Intestinal Epithelium. Experimental Study

This study was financed by the research groups CTS-115 (Universidad de Granada, Tissue Engineering) and UCM-911757 (Universidad Complutense de Madrid, Medical Hydrology).Since knowledge concerning the cellular and tissue substrate that explains the therapeutic action of mineral waters is generally very scarce, we address the different effects that Lanjaron-Capuchina mineral water exerts on the intestinal epithelium in an experimental model as a prototype of the sodium chloride-rich mineral waters used in digestive disorders. In the experimental protocol, two groups of five adult Wistar rats received unrestricted mineral water in their diet or mineral water directly into the gastrointestinal tract through a catheter. A third control group was given a standard diet and water ad libitum. Intestinal samples for scanning electron microscopy were analyzed according to standardized methods. The observations carried out by microscope after the administration of the sodium chloride-rich mineral water clearly indicate that the hypertonic action of this mineral water affects the structure of the intestinal epithelium. It modifies the microvilli absorption in terms of the groups of enterocytes and the secretion of goblet cells, but it particularly affects the epithelial renewal process, accelerating and stimulating cell extrusion. The type of extrusion mechanism observed by microscope allows us to affirm that, although this increased after direct administration, it does not generate an epithelial disruption as it occurs in other circumstances with other extrusion modalities.Universidad de Granada, Tissue Engineering CTS-115Universidad Complutense de Madrid, Medical Hydrology UCM-91175

Trabajo Social con poblaciones receptoras de inmigrantes: un modelo cuasi-experimental para fomentar actitudes multiculturales.

Este artículo forma parte de un proyecto transnacional entre España, Portugal, Italia y Grecia, subvencionado por el Programa de Desarrollo Tecnológico del Gobierno Autonómico Valenciano, que tiene como objetivo el fomento de actitudes tolerantes hacia inmigrantes en el sistema educativo. Se ha diseñado un modelo llamado EUROSUR que, puesto a prueba a través de experimentación, obtiene resultados satístactorios. La hipótesis principal es que el factor conocimiento (información a través de tres vías: audiovisual, escrita y oral) es una variable independiente determinante para atenuar e incluso modificar en los jóvenes la configuración de prejuicios racistas ante los inmigrantes. Los resultados evidencian cambios desde actitudes reaccionarias hacia otras más tolerantes, en los grupos experimentale

What are the main factors influencing the presence of faecal bacteria pollution in groundwater systems in developing countries?

Groundwater is the major source of drinking water in most rural areas in developing countries. This resource is threatened by the potential presence of faecal bacteria coming from a variety of sources and pollution paths, the former including septic tanks, landfills, and crop irrigation with untreated, or insufficiently treated, sewage effluent. Accurately assessing the microbiological safety of water resources is essential to reduce diseases caused by waterborne faecal exposure. The objective of this study is to discern which are the most significant sanitary, hydrogeological, geochemical, and physical variables influencing the presence of faecal bacterial pollution in groundwater by means of statistical multivariate analyses. The concentration of Escherichia coli was measured in a number of waterpoints of different types in a rural area located in the coast of Kenya, assessing both a dry and a wet season. The results from the analyses reaffirm that the design of the well and their maintenance, the distance to latrines, and the geological structure of the waterpoints are the most significant variables affecting the presence of E. coli. Most notably, the presence of faecal bacteria in the study area correlates negatively with the concentration of ion Na+ (being an indirect indicator of fast recharge in the study site), and also negatively with the length of the water column inside the well.Peer ReviewedPostprint (author's final draft

The Application of a System of Eye Tracking in Laparoscopic Surgery: A New Didactic Tool to Visual Instructions

Introduction: Laparoscopic surgery is an increasingly used technique, but it requires a high degree of learning, and communication between the operating room crew is considerably difficult. The use of eye tracking has been proposed as a didactic and evaluation tool in several settings, including in laparoscopy in simulators.Objectives: This study aimed to evaluate the usefulness of the use of eye tracking systems (Tobii glasses 2) in laparoscopic surgery as a didactic and assessment tool to improve communication in the operating room and improve patients' security.Methodology: An anonymous survey was sent to the students and medical teachers of a faculty of medicine and practicing doctors and residents. The message contained an explanation about the use of the Tobii glasses, a link to watch the video showing its use in a laparoscopic surgery, and the survey to complete after watching the video.Results: The survey was answered by 113 participants (51.3% medical students, 27.4% medical teachers, 18.6% practicing doctors, and 2.7% medicine residents). Eighty-three percent agreed with the usefulness of the “Tobii glasses” in the operating room for improving communication between the main surgeon and the assistant, for learning complex surgery techniques, for obtaining didactic videos, and for indicating anatomical structures. The item scored worst was the price of the glasses.Conclusions: It is possible to record and project expert gaze patterns in the operating room in real time using the Tobii glasses. This device allows improving communication among the surgical crew and the learning of residents and also improving the security of surgical patients

Actividades realizadas por los chicos y chicas fuera del centro escolar : una aplicación de ROSE

Se presenta un estudio sobre las diferencias de género ante las actividades que realizan los estudiantes fuera de las instituciones escolares, utilizando una de las escalas ROSE (Relevancia de la Educación Científica). Se observan diferencias significativas según el género. A la par, se extraen reflexiones sobre la importancia de tener en cuenta las experiencias previas de los estudiantes en relación al entorno para el desarrollo competencial en las clases de ciencias

Microbial community changes induced by Managed Aquifer Recharge activities: linking hydrogeological and biological processes

Managed Aquifer Recharge (MAR) is a technique used worldwide to increase the availability of water resources. We study how MAR modifies microbial ecosystems and its implications for enhancing biodegradation processes to eventually improve groundwater quality. We compare soil and groundwater samples taken from a MAR facility located in NE Spain during recharge (with the facility operating continuously for several months) and after 4 months of no recharge. The study demonstrates a strong correlation between soil and water microbial prints with respect to sampling location along the mapped infiltration path. In particular, managed recharge practices disrupt groundwater ecosystems by modifying diversity indices and the composition of microbial communities, indicating that infiltration favors the growth of certain populations. Analysis of the genetic profiles showed the presence of nine different bacterial phyla in the facility, revealing high biological diversity at the highest taxonomic range. In fact, the microbial population patterns under recharge conditions agree with the intermediate disturbance hypothesis (IDH). Moreover, DNA sequence analysis of excised denaturing gradient gel electrophoresis (DGGE) band patterns revealed the existence of indicator species linked to MAR, most notably Dehalogenimonas sp., Nitrospira sp. and Vogesella sp.. Our real facility multidisciplinary study (hydrological, geochemical and microbial), involving soil and groundwater samples, indicates that MAR is a naturally based, passive and efficient technique with broad implications for the biodegradation of pollutants dissolved in water.Peer ReviewedPostprint (published version