Comparative Analysis of Fall Risk Assessment Features in Community-Elderly and Stroke Survivors: Insights from Sensor-Based Data.

Fall-risk assessment studies generally focus on identifying characteristics that affect postural balance in a specific group of subjects. However, falls affect a multitude of individuals. Among the groups with the most recurrent fallers are the community-dwelling elderly and stroke survivors. Thus, this study focuses on identifying a set of features that can explain fall risk for these two groups of subjects. Sixty-five community dwelling elderly (forty-nine female, sixteen male) and thirty-five stroke-survivors (twenty-two male, thirteen male) participated in our study. With the use of an inertial sensor, some features are extracted from the acceleration data of a Timed Up and Go (TUG) test performed by both groups of individuals. A short-form berg balance scale (SFBBS) score and the TUG test score were used for labeling the data. With the use of a 100-fold cross-validation approach, Relief-F and Extra Trees Classifier algorithms were used to extract sets of the top 5, 10, 15, 20, 25, and 30 features. Random Forest classifiers were trained for each set of features. The best models were selected, and the repeated features for each group of subjects were analyzed and discussed. The results show that only the stand duration was an important feature for the prediction of fall risk across all clinical tests and both groups of individuals.

Random Forest for Automatic Feature Importance Estimation and Selection for Explainable Postural Stability of a Multi-Factor Clinical Test.

Falling is a common incident that affects the health of elder adults worldwide. Postural instability is one of the major contributors to this problem. In this study, we propose a supplementary method for measuring postural stability that reduces doctor intervention. We used simple clinical tests, including the timed-up and go test (TUG), short form berg balance scale (SFBBS), and short portable mental status questionnaire (SPMSQ) to measure different factors related to postural stability that have been found to increase the risk of falling. We attached an inertial sensor to the lower back of a group of elderly subjects while they performed the TUG test, providing us with a tri-axial acceleration signal, which we used to extract a set of features, including multi-scale entropy (MSE), permutation entropy (PE), and statistical features. Using the score for each clinical test, we classified our participants into fallers or non-fallers in order to (1) compare the features calculated from the inertial sensor data, and (2) compare the screening capabilities of the multifactor clinical test against each individual test. We use random forest to select features and classify subjects across all scenarios. The results show that the combination of MSE and statistic features overall provide the best classification results. Meanwhile, PE is not an important feature in any scenario in our study. In addition, a t-test shows that the multifactor test of TUG and BBS is a better classifier of subjects in this study.

La genética del trastorno antisocial de la personalidad: Una revisión de la bibliografía / Genetics of antisocial personality disorder: review of the literature

The antisocial personality disorder (ASPD) is characterized by an incapacity for an individual to adapt himself or herself to the social norms. These social norms are extremely important because they govern many aspects of behavior during adolescence and adulthood. Patients with ASPD typically have irritability problems and aggressive feelings toward other people. These aggressive feelings toward other people are expressed in a context of threat and intimidation. The ASPD is less common in clinical settings comparing the total population, in which the prevalence is 1.1. The familial aggregation for ASPD has been registered, in which the 40-50% of the variance can be explained to genetic influences. Most of the studies of ASPD in molecular genetics have been applying the hypothesis of association of candidate genes, focusing on genes associated with neurotransmission pathways. This has been greatly relevant to the monoamine oxidase gene (MAO). Genes that promote specific behavior between individuals must have been selected through the process of natural selection. Aggressive behaviors and other types of behavior that have an evolutionary origin are similar in the fact that they have to be codified in the genes and will later be transmitted to their descendants.

El trastorno antisocial de la personalidad (TAP) consiste en una incapacidad para adaptarse a las normas sociales que habitualmente rigen numerosos aspectos de la conducta de las personas en la adolescencia y la edad adulta. Los pacientes con TAP característicamente tienen problemas de irritabilidad y sentimientos agresivos hacia los demás, los cuales se expresan en el contexto de la amenaza o la intimidación. El TAP es menos común en la clínica comparándolo con la población general en la que se reporta una prevalencia media del 1.1. Se ha registrado una agregación familiar para el TAP en la que el 40-50% de la varianza puede ser explicada por influencias genéticas. La mayoría de los estudios de genética molecular en el TAP se han realizado utilizando la hipótesis basada en los estudios de asociación con genes candidatos, enfocándose en los genes relacionados a vías de neurotransmisión, siendo uno de los más relevantes, hasta el momento, el gen para la monoamino oxidasa (MAOA). Aquellos genes que promueven que cierta conducta exista entre los individuos debieron haberse elegido a través del proceso de la selección natural. De manera similar a otros comportamientos que tienen orígenes evolutivos, los comportamientos agresivos también deben ser codificados en los genes, que a la postre serán transmitidos a la descendencia.

Farmacología y toxicología de Guatteria gaumeri y alfa-asarona / Pharmacology and toxicology of Guatteria gaumeri

La planta Guatteria gaumeri Greenman (Annonaceae) se utiliza en medicina tradicional para el tratamiento de la hipercolesterolemia y la colelitiasis. El principio activo mayoritario es la alfaasarona que ha sido aislado y posteriormente sintetizado, además de 16 análogos derivados de 4-propenil-1,2-dimetoxibencenos 5-sustituidos. Dosis de 80 mg/kg de alfa-asarona y de los derivados amino (NH2-) y metoxi (MeO-), administradas oralmente por siete días a ratas hipercolesterolémicas, produjeron decrementos del 57.3, 37.5 y 46.9 por ciento del colesterol y del 42.5, 67.6 y 17.2 por ciento de los triglicéridos, respectivamente; al alfa-asarona redujo además 80.6 por ciento del peso de los cálculos biliares en hamsters. Algunos de los otros análogos también presentaron actividad hipolopidémica importante. Estudios en hepatocitos sugiere que parte del efecto lipidémico es debido a disminución en la secreción de los lípidos. La alfa-asarona no produjo toxicidad en ratas dada por vía oral durante 28 días, con dosis de 10 ó 50 mg/kg y tampoco genotoxicidad mediante la prueba de dominantes letales. Sin embargo, la exposición in vitro de hepatocitos a concentraciones micromolares indujo alteraciones morfológicas, acumulación de triacilglicerol e inhibición de la síntesis y secreción de proteínas. A su vez, las pruebas de Ames y de frecuencia de intercambio de cromátides hermanas en linfocitos humanos, sí revelaron genotoxicidad. No se produjo teratogenia en ratas administrada durante la organogénesis, pero en ratones se encontró hidrocefalia, defectos en esqueleto, y baja de peso corporal. El efecto tóxico de la alfa-asarona plantea precausión en el uso de la planta en tanto no se efectúen investigaciones en otras especies animales; es importante también analizar la toxicología de los compuestos análogos