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Characterization of bidimensional polymeric films at the air-water interface in the Langmuir trough, despite being a recurrent topic, usually refers to films of already formed polymeric materials, with very scarce reports on direct polymerization at the air-water interface. In the present work, we studied the photo-polymerization of stearyl methacrylate directly at the air-water interface under a nitrogen atmosphere, with the radical initiator solubilized in the aqueous phase. Two-dimensional (2D) polymerization was monitored by measuring the pressure-area isotherm at different irradiation times. The polymerization leads to a film with an isotherm different from that observed for the monomer, where the surface pressure is directly related to the irradiation time. The shape of this isotherm confirms the presence of a compressed liquid phase, where a higher order can be attained as a consequence of stronger packing forces involving polymer chains. The presence of inter-chain interactions allows rearrangements on the surface of the subphase, and even before the collapse a dense 2D ordering (with a solid phase-like behavior) can be observed. We present a new one-step, solvent-free procedure to obtain a photo-polymeric film directly at the air-water interface, which can be transferred to a solid surface by the Langmuir-Blodgett method, allowing film preparation of controlled thickness. Films were characterized by measuring properties such as thickness, roughness, and hydrophobicity and comparing them with films obtained from a conventional polymer. We report the differences between the interfacial behavior of amphiphilic molecules and nanomaterials such as films obtained by photo-polymerization, PSMA, directly on the air-water interface.

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The present study investigated the structure of the Spanish version of the Iowa-Netherlands Comparison Orientation Measure (INCOM-E), an 11-item measure that assesses individual differences in social comparison orientation (SCO), i.e., the extent to which people compare themselves with others. Data came from samples from Spain (n = 1,133) and Chile (n = 2,757). Confirmatory Factor Analyses and Mokken Scale Analyses supported in both samples not the assumed two-factor structure, but a single factor structure, consisting of eight items. The resulting eight-item version of the INCOM-E was reliable in both samples, according the Gutmann's lambda-2 (.82 in Spain and .83 in Chile), and correlated very strongly with the full-length INCOM-E (.93 in Spain and .97 in Chile). In both samples, there were significant sex differences, ps < .001 with small effect sizes, ƞ2 in both samples = .01,but in the Spanish sample women scored higher, and in the Chilean sample men scored higher in SCO. The relationship with age was negative and significant (ps < .001) in both samples, albeit small (r = .22 in Spain and .13 in Chile) Based on the present research, it is advised to use the shortened eight-item version of the INCOM-E in Spanish speaking countries.

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The SARS-CoV-2 virus and the associated disease COVID-19 has quickly become a pandemic. People with underlying chronic diseases or in an immunosupressed state are at risk of having a worse outcome. Cirrhotic patients and liver transplant recipients are considered to be in this higher risk group due to their immunosuppressed state. The aim of this article is to present recommendations based on expert opinion regarding the management of patients with compensated and decompensated liver pathologies who take medication for their immunosuppressed state in medical check-ups and basic treatment management both of patients with and without the COVID-19 disease.

El virus SARS-CoV-2 asociado a la enfermedad COVID-19, se han instalado a nivel de pandemia mundial. Las personas portadoras de enfermedades crónicas o estados de inmunosupresión se encuentran en riesgo de desarrollar un curso más grave. Se considera que los pacientes con cirrosis hepática, patología autoinmune o trasplante hepático se encontrarían dentro de este grupo de mayor riesgo por su estado de inmunosupresión. Presentamos recomendaciones de manejo basadas en opinión de experto, en pacientes con patología hepática compensada y descompensada e inmunosuprimidos farmacológicos, en relación a controles médicos y manejo de terapia de base tanto en pacientes sin COVID-19 como en pacientes infectados.

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The factors governing bacterial adhesion to substrates with different topographies are still not fully identified. The present work seeks to elucidate for the first time and with quantitative data the roles of bacterial elasticity and shape and substrate topography in bacterial adhesion. With this aim, populations of three bacterial species, P. aeruginosa DSM 22644, B. subtilis DSM 10, and S. aureus DSM 20231 adhered on flat substrates covered with electrospun polycaprolactone fibers of different diameters ranging from 0.4 to 5.5 µm are counted. Populations of bacterial cells are classified according to the preferred binding sites of the bacteria to the substrate. The colloidal probe technique was used to assess the stiffness of the bacteria and bacteria-polymer surface adhesion energy. A theoretical model is developed to interpret the observed populations in terms of a balance between stiffness and adhesion energy of the bacteria. The model, which also incorporates the radius of the fiber and the size and shape of the bacteria, predicts increased adhesion for a low level of stiffness and for a larger number of available bacteria-fiber contact points. Te adhesive propensity of bacteria depends in a nontrivial way on the radius of the fibers due to the random arrangement of fibers.

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Surfaces were prepared with polyelectrolyte derivatives of poly(styrene- alt-maleic anhydride) (PSMA) functionalized with amino acids of different hydropathy indices, with the aim of evaluating the effect of the chemical functionality of polyelectrolytes on SH-SY5Y neuroblastoma cell adhesion. Functionalizing PSMA derivatives with l-glutamine, l-methionine, and l-tyrosine yielded PSMA-Gln, PSMA-Met, and PSMA-Tyr polyelectrolytes, respectively. We first studied the adsorption behavior of PSMA functionalized with amino acids on silicon wafer surfaces modified with 3-aminopropyltriethoxysilane at pH 4.0 and 7.0 and at low and high ionic strengths. The highest rate of polyelectrolyte adsorption was at pH 4.0 and high ionic strength and was higher with the glutamine and tyrosine films. The advance contact angles (θA) of the polyelectrolyte surfaces showed a moderate effect of ionic strength and pH on polyelectrolyte film wettability, with PSMA-Tyr being slightly more hydrophobic. Atomic force microscopy images of the polyelectrolyte surfaces showed two types of morphology: the well-defined globular nanostructure of PSMA-Met and PSMA-Tyr and densely packed nanofibrous-like structure of PSMA-Gln. The highest level of ionic strength caused a slight decrease in the size of the nanostructure that formed the surface domains, which was reflected in the degree of surface roughness. Cell adhesion assays with the polyelectrolyte film showed that SH-SY5Y neuroblastoma cells cultured on PSMA-Met present a well-extended morphology characterized by a stellate shape, with five or more actin-rich thin processes, whereas SH-SY5Y cells that were seeded on PSMA-Gln and PSMA-Tyr have a round morphology, with fewer and shorter processes. These results indicate that it is possible to modulate the surface characteristics of polyelectrolyte films based on their chemical functionality and environmental parameters such as pH and ionic strength in order to evaluate their effect on cell adhesion. Thus, surfaces prepared from polyelectrolytes functionalized with amino acids are an attractive and simple platform for cell adhesion, which can be used in developing biomaterials with modulated surface properties.

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The use of implants carries on a series of problems, among them infections, poor biocompatibility, high levels of cytotoxicity, and significant mechanical differences between implants and host organs that promote stress shielding effects. These problems indicate that the materials used to make implants must meet essential requirements and high standards for implantations to be successful. In this work, we present the synthesis, characterization and evaluation of the antibiofilm, mechanical, and thermal properties, and cytotoxic effect of a nanocomposite-based scaffold on polyurethane (PU) and gold nanoparticles (AuNPs) for soft tissue applications. The effect of the quantity of AuNPs on the antibacterial activity of nanocomposite scaffolds was evaluated against Staphylococcus epidermidis and Klebsiella spp., with a resulting 99.99% inhibition of both bacteria using a small quantity of nanoparticles. Cytotoxicity was evaluated with the T10 1/2 test against fibroblast cells. The results demonstrated that porous nanogold/PU scaffolds have no toxic effects on fibroblast cells to the 5 day exposition. With respect to mechanical properties, stress-strain curves showed that the compressive modulus and yield strength of PU scaffolds were significantly enhanced by AuNPs (by at least 10 times). This is due to changes in the arrangement of hard segments of PU, which increase the stiffness of the polymer. Thermogravimetric analysis showed that the degradation onset temperature rises with an increase in the quantity of AuNPs. These properties and characteristics demonstrate that porous nanogold/PU scaffolds are suitable material for use in soft tissue implants.

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El craving se define como el deseo o ansias por introducir una sustancia en el cuerpo. La American Psychiatric Association ha propuesto que para adicciones conductuales, que implican el realizar algún tipo de acción, se consideren los mismos criterios que para una adicción a sustancias. Las naturalezas de los objetos son diferentes por lo que surge el desafío de analizar si el abordaje de las adicciones conductuales debe realizarse bajo los criterios de una adicción a sustancias. Se seleccionaron 23 artículos sobre la materia los que permitieron elaborar un modelo teórico explicativo de craving hacia Facebook y Mensajería instantánea. El modelo consta de tres dimensiones: intensidad del deseo, grado de control y expectativas de calma. Se propone estudiar la forma en que estas dimensiones se presentan en adicciones conductuales para reconstruir el concepto en este campo, y generar un instrumento que permita su evaluación.

Craving is defined as the desire to introduce a substance in the body. The American Psychiatric Association proposed to research if behavioral addictions can be assessed with the substance addictions criteria. Nature of both objects are different so the challenge of analyze if assessment of behavioral addictions can be done with the same criteria of substance addictions. 23 articles about substance addictions were selected to elaborate a theoretical explicative model of craving to start research craving to Facebook and Instant Messaging. The model consists of three dimensions: desire intensity, degree of control and calm expectations. It is proposed to study how these dimensions are in behavioral addictions to rebuild the concept in this area, and generate an instrument to asses it.

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Non-alcoholic fatty liver disease (NAFLD) is currently considered in Chile and worldwide, as the main cause of cirrhosis and liver transplantation. It is therefore one of the main public health objectives for reducing its prevalence. In last years, it was suggested that the intestinal microbiota (IM) might contribute to the pathophysiology of NAFLD, as well as in the progression toward nonalcoholic steatohepatitis (NASH) and cirrhosis. It is known that changes in the composition of IM are associated with alterations in intestinal permeability and the production of inflammatory metabolites. These alterations are part of the pathophysiological mechanisms leading to the development of NASH. However studies on MI in patients with NAFLD and NASH in Chile are scarce. Through a research grant, recently awarded at the Hospital Clínico Universidad de Chile, we aim to confirm and characterize the intestinal dysbiosis associated with NAFLD in Chilean patients and to establish the relationship between the changes in microbial composition with the progression of liver damage. The description of these alterations represents an opportunity to explore new therapeutic approaches for future interventions. In effect, through the restoration of an intestinal microbial environment towards homeostasis in these patients, we expect to reverse or improve the progression of damage provoked by this disease. (AU)

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Abstract Using a cross-sectional, non-experimental design, the hypothesis that the mental health state of assessed immigrants differs according to the acculturation strategy used, was tested. To this end, the mean difference in physiological symptoms, social roles and relationships among participants categorized by type of acculturation strategy, i.e. bicultural integration, separation, isolation and assimilation, was evaluated. The sample consisted of 431 Peruvian and Colombian immigrants, residing in the city of Antofagasta, Chile. To evaluate acculturation, the Revised Acculturation Attitudes Scale by Basabe, Zlovina and Paez was used, and for the mental health assessment, the Self-Assessment Questionnaire OQ-45.2 was applied. Findings show that separation was the most commonly used strategy by Colombians, while in the Peruvian population it was assimilation. Similarly, the Colombian population reported a greater presence of symptoms of mental health problems in all dimensions and in the overall scale than the Peruvian population. In the overall sample, the individuals who used assimilation as their acculturation strategy tended to report more symptoms and difficulties in interpersonal relationships. The data provide evidence that the acculturation strategies used result in a greater or lesser presence of psychopathological symptoms.

Resumo Mediante um desenho não experimental de tipo transversal contrastou-se a hipótese de que o estado de saúde mental dos imigrantes avaliados difere segundo a estratégia de aculturação que utilizem. Para isso, avaliou-se a diferença média em sintomatologia, papel social e relações interpessoais entre os participantes agrupados por tipo de estratégia de aculturação (integração ou biculturalidade, separação, isolamento e assimilação) numa amostra de 431 imigrantes peruanos e colombianos residentes na cidade de Antofagasta, Chile. Para avaliar a aculturação utilizou-se a Escala revisada de atitudes com relação à aculturação de Basabe, Zlovina e Páez, e para avaliar a Saúde Mental aplicou-se o questionário de Autoavaliação OQ-45.2. Como resultado verificou-se que a estratégia mais utilizada pelos colombianos foi a separação, e pelos peruanos, a assimilação, além de que os primeiros apresentaram maior presença de sintomas de problemas de saúde mental em todas as dimensões e na escala total, em comparação com a população peruana. Na amostra total, os indivíduos que utilizaram a estratégia assimilação tiveram uma maior presença de sintomatologia e dificuldades nas relações interpessoais. Os dados contribuem com evidência com relação a que as estratégias de aculturação utilizadas incidiriam numa maior ou menor presença de sintomatologia psicopatológica.

Resumen Mediante un diseño no experimental de tipo transversal se contrastó la hipótesis de que el estado de salud mental de los inmigrantes evaluados difiere según la estrategia de aculturación que utilicen. Para esto se evaluó la diferencia de medias en sintomatologia, rol social y relaciones interpersonales entre los participantes agrupados por tipo de estrategia de aculturación (integración o biculturalidad, separación, aislamiento y asimilación) en una muestra de 431 inmigrantes peruanos y colombianos residentes en la ciudad de Antofagasta, Chile. Para evaluar la aculturación se utilizó la Escala revisada de actitudes hacia la aculturación de Basabe, Zlovina y Páez, y para evaluar la Salud Mental se aplicó el cuestionario de Autoevaluación OQ-45.2. Como resultado se encontró que la estrategia más utilizada por los colombianos fue la separación, y por los peruanos, la asimilación, además de que los primeros reportaron mayor presencia de sintomas de problemas de salud mental en todas las dimensiones y en la escala total, en comparación con la población peruana. En la muestra total, los individuos que utilizaron la estrategia asimilación presentaron un mayor reporte de sintomatologia y dificultades en las relaciones interpersonales. Los datos aportan evidencia con respecto a que las estrategias de aculturación utilizadas incidirian en una mayor o menor presencia de sintomatologia psicopatológica.

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Resumen: Introducción: La falta de adherencia a la medicación antipsicótica sigue siendo un problema en el tratamiento de pacientes con esquizofrenia, más aún en población indígena. Objetivo: Evaluar las diferencias en la adherencia farmacológica, medida a través de la actitud hacia los antipsicóticos, entre pacientes aymara y no-aymara con esquizofrenia. Método: La muestra estuvo compuesta por pacientes que recibían tratamiento en los Servicios Públicos de Salud Mental de Bolivia (32.8%), Perú (33.6%) y Chile (33.6%). Se utilizó el Inventario de Actitud hacia la Medicación (DAI-10); la Escala Barnes de Acatisia (EBA) como medida de efectos secundarios y la Escala para el Síndrome Positivo y Negativo de la Esquizofrenia (PANSS) para evaluar la severidad del trastorno. Resultados: Los pacientes aymara presentan una menor adherencia que los pacientes no-aymara, sin embargo, estas diferencias no fueron significativas (t = 1.29; p = 0.19). La severidad del trastorno y la edad mostraron una asociación significativa con la adherencia, observándose que pacientes más jóvenes y con mayor sintomatología presentan una actitud más negativa hacia los fármacos. Discusión y conclusión: Se discute cómo las dinámicas migratorias han promovido la pérdida de tradiciones y costumbres propias de la etnia promoviendo la adopción de estilos de vida nuevos y cada vez más interculturales, e incluso cambiando su concepción de la enfermedad mental. Los profesionales tratantes deben estar conscientes de no aplicar estereotipos en cuanto a la relación etnia-antipsicóticos.

Abstract: Introduction: Non-adherence to antipsychotic medication remains a complex problem in the treatment of schizophrenia patients, especially in indigenous population. Objective: The aim of the study was to assess the differences in drug adherence, measured by the attitude towards the antipsychotics among Aymara and Non-Aymara patients with schizophrenia. Method: The sample consisted of patients receiving treatment in the Mental Health Public Services in Bolivia (32.8%), Peru (33.6%) and Chile (33.6%). We used the Drug Attitude Inventory (DAI-10); the Barnes Akathisia Scale (BAS), as a measure of side effects, and the Positive and Negative Syndrome Scale (PANSS) to assess the severity of the disorder. Results: The findings showed that Aymara patients present less adherence than Non-Aymara people; however, these differences were not significant (t = 1.29; p = 0.19). The severity of the disorder, as well as the age, showed a significant association with adherence, revealing that younger patients and with greater symptoms presented a more negative attitude toward the drugs. Discussion and conclusion: The lack of significant differences between the groups responds to three possible reasons: 1. This sample of indigenous patients is integrated on Mental Health Services that offer a clear biomedical approach where drug therapy is the primary treatment. 2. It is possible that these indigenous patients are changing their conception of mental disorder, and 3. A significant number of families have migrated to urban areas. These migratory dynamics have promoted the loss of traditions and customs of the ethnic group, which gradually adopts new and intercultural lifestyles. Professionals should be warned about applying stereotypes regarding the relationship between ethnicity and antipsychotics.