Resumo A ligação de um ligante com um receptor molecular induz um sinal que viaja através do receptor, chegando ao domínio interno e disparando uma cascata de resposta. Em trabalhos anteriores em receptores de células T e sua ligação com antígenos estranhos, observamos a presença de padrões moleculares planares capazes de gerar campos eletromagnéticos dentro das proteínas. Esses planos mostraram um comportamento coerente (sincronizado), replicando, instantaneamente, no domínio intracelular o que ocorreu no domínio extracelular, enquanto o ligante era acoplado. No presente estudo, examinamos essa transdução – a capacidade de um sinal de acoplamento de penetrar profundamente a molécula receptora e induzir uma resposta. Verificamos a presença de um comportamento coerente em sistemas diversos de receptor-ligante. Para apreciar essa diversidade, apresentamos quatro sistemas bioquímicos diferentes: TCR-peptídeo, ADP-bomba de cálcio, hemoglobina-oxigênio e gp120-CD4 acoplamento viral. A confirmação de transdução molecular sincronizada em cada um desses sistemas sugere que o mecanismo proposto ocorreria em todos os sistemas bioquímicos receptor-ligante.

Abstract The coupling of a ligand with a molecular receptor induces a signal that travels through the receptor, reaching the internal domain and triggering a response cascade. In previous work on T-cell receptors and their coupling with foreign antigens, we observed the presence of planar molecular patterns able to generate electromagnetic fields within the proteins. These planes showed a coherent (synchronized) behavior, replicating immediately in the intracellular domain that which occurred in the extracellular domain as the ligand was coupled. In the present study, we examined this molecular transduction - the capacity of the coupling signal to penetrate deep inside the receptor molecule and induce a response. We verified the presence of synchronized behavior in diverse receptor-ligand systems. To appreciate this diversity, we present four biochemically different systems - TCR-peptide, calcium pump-ADP, haemoglobin-oxygen, and gp120-CD4 viral coupling. The confirmation of synchronized molecular transduction in each of these systems suggests that the proposed mechanism would occur in all biochemical receptor-ligand systems.

Introduction: In Chile, coal-fired power plants (CTEC) operate represents public health problems due to the health consequences for the population. Damage to the respiratory system is reported. Materials and Methods: Ecological study to evaluate hospital discharges in people living in cities where CTEC operates (Tocopilla and Huasco) were compared to a control city without CTEC (Caldera), all of them with similar sociodemographic conditions. Morbidity rates and Standardized Morbidity Ratios (SMR) were calculated. Results: The respiratory disease morbidity rate in Tocopilla (2016) was 152.5 per 10,000 inhabitants (habs) and for Huasco it is 135.2 per 10,000 inhabitants. In the control city, Caldera, the rate is 40.9 per 10,000 habs. In addition, the inhabitants of Tocopilla have a 2.42 times increased risk of bronchitis or bronchiolitis, 90% higher risk of chronic lower respiratory diseases and 2.14 times more risk of asthma sickness. In Huasco, the population is 2.49 times more at risk of lower respiratory diseases compared to the region and 3.19 times more at risk of asthma. Conclusions: Asthma and bronchitis are the pathologies that showed the greatest risks in the cities of Tocopilla and Huasco. Our findings are similar to other research conducted in communities exposed to coal-fired power plants. Urgent action is needed to protect the health of the population.

Resumen Introducción: En Chile, el funcionamiento de las Centrales Termoeléctricas de Carbón (CTEC) representan un problema de salud pública debido a las consecuencias sanitarias que tienen en la población. Se han notificado daños en el sistema respiratorio. Materiales y Métodos: Se realizó un estudio ecológico, para evaluar los egresos hospitalarios de las personas que viven en las ciudades donde operan las CTEC (Tocopilla y Huasco), se comparó con una ciudad de control sin CTEC (Caldera), las comunas evaluadas tienen condiciones sociodemográficas similares. Se calcularon las tasas de morbilidad y tasas de morbilidad estandarizadas (SMR). Resultados: La tasa de morbilidad por enfermedades respiratorias en Tocopilla (2016) fue de 152,5 por 10.000 habitantes (habs) y para Huasco es de 135,2 por 10.000 habs. En la ciudad control, Caldera, la tasa es de 40,9 por 10.000 habs. Además, los habitantes de Tocopilla tienen 2,42 más riesgo de padecer bronquitis o bronquiolitis, 90% más riesgo de presentar enfermedades crónicas de las vías respiratorias bajas y 2,14 veces más riesgo de enfermar por asma. En Huasco, la población tiene 2,49 veces más riesgo de padecer enfermedades de las vías respiratorias inferiores con respecto a la región y 3,19 veces más riesgo de presentar asma. Conclusiones: El asma y la bronquitis, son las patologías que mostraron mayores riesgos en las ciudades de Tocopilla y Huasco. Nuestros hallazgos son similares a otras investigaciones realizadas en comunidades expuestas a centrales termoeléctricas de carbón. Es necesario tomar medidas urgentes para proteger la salud de la población.

Abstract: Coal-fired power plants (CFPP) represent a health risk to the exposed communities. A review of national and international scientific literature was made focused on the health effects on children and exposure to air emissions from CFPP. Twenty-one articles were included for full-text review, where effects on child health mainly related to the biomarkers presence of exposure and effect, pe rinatal, neurobehavioral and respiratory damages were measured. Exposure to CFPP emissions in pregnancy was associated with low birth weight and very low birth weight, shorter height, smaller head circumference (HC) diameter, and prematurity; the HC diameter increased in newborns after the CFPP closure. Lower coefficient of development (CD) and intelligence quotient (IQ) were found in children exposed to CFPP emissions compared with unexposed ones; CD increased when the plant was closed. On the other hand, living in areas with mercury emission sources (associated with CFPP and cement plants that work with coal) was associated with an increased risk of autism. In respira tory health, the articles were consistent with reporting lower pulmonary function in children living in areas exposed to coal combustion sources compared with groups of unexposed children. There is a great need to open the debate in Chile on the controllable risks faced by the child population as a result of power generation plants located in Chile.

Resumen: Las centrales termoeléctricas (CTE) a carbón representan un riesgo para la salud de las comunidades expuestas. Se realizó una revisión de la literatura científica nacional e internacional enfocada en los efectos en salud de niños y la exposición a emisiones al aire provenientes de CTE a carbón. Se inclu yeron 21 artículos para su revisión en texto completo, donde se midieron efectos en salud infantil relacionados a presencia de biomarcadores de exposición y efecto, daños perinatales, neuroconductuales y respiratorios principalmente. La exposición a emisiones de CTE a carbón en el embarazo se asoció a niños con bajo peso y muy bajo peso al nacer, menor talla, menor diámetro de Circunfe rencia del Cráneo (CC) y prematuridad; el diámetro de CC aumentó en recién nacidos después del cierre de CTE. Se encontraron menor coeficiente de desarrollo (CD) y coeficiente intelectual (CI) en niños expuestos a emisiones de CTE a carbón comparados con no expuestos; CD aumentó cuando la central fue cerrada. Por otro lado, vivir en zonas con fuentes de emisión de mercurio (asociadas a CTE y plantas de cemento que funcionan con carbón) se asoció con mayor riesgo de autismo. En salud respiratoria, los artículos fueron consistentes en reportar menor función pulmonar en niños residentes en zonas expuestas a fuentes de combustión de carbón comparados con grupos de niños no expuestos. Es muy necesario abrir el debate en Chile sobre los riesgos controlables a los que se enfrenta la población infantil a consecuencia de plantas generadoras de energía instaladas en Chile.

Background: Nitrate exposure may be associated with thyroid gland dysfunction. Aim: To review the available evidence about the relationship between nitrates in drinking water and thyroid gland dysfunction. Material and Methods: A wide search was performed using Medline, Cochrane, Lilacs, IBECS and Scielo databases using pertinent keywords, finding a total of 66 related studies. After filtering and in depth reviewing, a total of 12 studies were included in this review. Results: The main results reveal the importance of this ion for human health, finding evidence both in animals and human beings that suggest pathological changes in the gland as its relationship with the occurrence of subclinical hypothyroidism, and potentially cancer of the thyroid gland. In Chile, nitrate is not considered a critical contaminant so its regular measuring and control is not enforced. Conclusions: In light of the present review we believe that there is evidence to consider nitrate as a critical contaminant whose measurement, registration and correct implementation of valid policies would have a direct benefit for the population of this country. Without this information, it is not possible to quantify the damage to human health, especially in vulnerable groups residing in areas at greatest risk of exposure.

We described and compared the diets of two sympatric Andean camelids, during the humid season (austral summer) in a site of Northern Chile, in presence of domestic livestock. Results indicate that: 1) grasses and shrubs are the main component in the diet of both camelids, 2) shrubs were more consumed by V. vicugna; 3) V. vicugna and L. guanicoe used the same trophic resources but in different proportions; 4) in mountain environments, wetlands exploitation by wild camelids seems restricted by domestic cattle, which would cause the displacement of Vicuñas and Guanacos to suboptimal habitat for feeding.

Describimos y comparamos la dieta de dos poblaciones simpátricas de camélidos silvestres, durante la estación húmeda (verano) en un sector del norte de Chile en presencia de ganado domesticado. Nuestros resultados indican que: 1) gramíneas y arbustos son el principal componente de la dieta de ambos camélidos; 2) arbustos fueron consumidos principalmente por V. vicugna; 3) V. vicugna and L. guanicoe utilizan los mismos recursos tróficos pero en diferentes proporciones; 4) en ambientes de montaña, el uso de vegas altoandinas por parte de camélidos silvestres estaría siendo restringido por la presencia de ganado domesticado, el cual provocaría el desplazamiento de ambos camélidos a zonas subóptimas de alimentación.

RESUMO Foi realizado um experimento com o objetivo de avaliar um aditivo alimentar contendo atividade de epoxidase de uma bactéria (Mycofix-S) como proteção potencial contra os efeitos adversos de uma dieta com 2,5ppm de toxina T-2 em frangos de corte machos. Um total de 144 pintos machos Ross 308 de um dia de idade foram marcados na asa individualmente e alocados em um de quatro grupos experimentais: grupo 1: controle negativo, sem toxina T-2 ou aditivo; grupo 2: 2,5g/kg de Mycofix-S; grupo 3: controle positivo, 2,5ppm de toxina T-2; grupo 4: 2,5ppm de toxina T-2 + 2,5g/kg de Mycofix-S. Alimento e água foram fornecidos ad libitum por 28 dias (dias um a 28 de idade). Cada tratamento experimental foi replicado seis vezes, com seis pintos por gaiola de replicação. As variáveis de resposta incluíram parâmetros de desempenho, atividade sérica de fosfatase alcalina (ALP) e amilase, peso relativo de órgãos selecionados e histologia do sistema digestivo superior. A toxina T-2 a 2,5ppm diminuiu significativamente (P = 0.016) o ganho de peso corporal aos 28 dias e o consumo de alimento acumulado, sem afetar a conversão alimentar. O aditivo diminuiu os efeitos adversos. As atividades séricas das enzimas não foram afetadas significativamente (P>0.05) nos quatro grupos experimentais, porém, quando os dados dos grupos que receberam a toxina T-2 foram combinados e comparados com o pool de dados dos grupos sem toxina, foi observado um decréscimo significativo da atividade de amilase nos frangos que receberam a toxina T-2. O exame histológico do sistema digestivo superior revelou lesões em boca, esôfago, pró-ventrículo, moela e duodeno nos frangos alimentados com toxina T-2 sem aditivo. Frangos alimentados com toxina T-2 mais aditivo mostraram lesões nos mesmos tecidos, exceto no duodeno. Os resultados do presente estudo mostram que a adição de 2,5g/kg do aditivo alimentar testado protege contra os efeitos adversos sobre o desempenho e a integridade da mucosa duodenal.

ABSTRACT A trial was conducted to evaluate a feed additive containing epoxidase activity from a bacterium (Mycofix-S) as a potential protection against the adverse effects of 2.5 ppm dietary T-2 toxin in male growing broiler chickens. A total of 144 one-day-old Ross 308 male chicks were individually wing-banded and allotted into each of the four experimental groups. Group 1: negative control, no T-2 toxin or additive; group 2: Mycofix-S, 2.5 g/kg; group 3: positive control, 2.5 ppm T-2 toxin; group 4: 2.5 ppm T-2 toxin + 2.5 g/kg Mycofix-S. Feed and water were provided ad libitum for 28 days (days 1 to 28 of age). Each experimental treatment was replicated 6 times, with 6 birds per replicate pen. Response variables included performance parameters, serum activity of alkaline phosphatase (ALP) and amylase, relative weight of selected organs and histology of the upper digestive system. T-2 toxin at 2.5 ppm significantly (P = 0.016) decreased the 28-day body weight gain and cumulative feed intake without affecting feed conversion. The feed additive counteracted these adverse effects. Serum enzyme activities were not significantly (P>0.05) affected for the four experimental groups but when data from the groups receiving T-2 toxin was pooled and compared against the pooled data from groups without the toxin a significant decrease in amylase activity was observed in chickens receiving T-2 toxin. The histological examination of the upper digestive system revealed lesions in mouth, esophagus, proventriculus, gizzard and duodenum in the chickens fed T-2 toxin without the additive. Chickens fed T-2 toxin plus the additive showed lesions in the same tissues except in the duodenum. The results of the present study show that the addition of 2.5 g/kg of the feed additive tested protects against adverse effects on performance and also the integrity of the duodenal mucosa.

The incidence of obesity in Chilean adult population reaches up to 25.1%, according to statistics from 2013. Bariatric surgery is an alternative that has proven weight loss and resolution of comorbidities significant long term. For this reason are routine procedures in different health institutions. However, its massification and safety are not free of complications, which can be detected and treated early with the help of radiological images. The aim of this paper is to describe the most common postoperative complications of the sleeve gastrectomy and its diagnosis using different imaging techniques, mainly fluoroscopic study contrasted of the the esophagus-stomach-duodenum and contrasted enhanced computed tomography (CT) of the abdomen and pelvis. Bariatric surgeries are now routine procedures for treatment of morbid obesity. Knowledge of early and late complications and diagnosis of these using different imaging techniques allow adequate treatment, control and decreased postoperative morbidity and mortality.

La incidencia de obesidad en la población adulta chilena alcanza hasta un 25,1%, de acuerdo a cifras del año 2013. Las cirugías bariátricas son una alternativa que ha demostrado una baja de peso y resolución de comorbilidades significativas a largo plazo. Por este motivo son procedimientos rutinarios en las diferentes instituciones de salud. No obstante su masificación y seguridad, no están exentas de complicaciones, las que se pueden detectar y tratar precozmente con la ayuda de imágenes radiológicas. El objetivo de este trabajo es describir las complicaciones postquirúrgicas más frecuentes de la gastrectomía en manga y el diagnóstico mediante diferentes técnicas de imagen, principalmente el estudio fluoroscópico contrastado del esófago-estómago-duodeno y tomografía computada (TC) contrastada de abdomen y pelvis. El conocimiento de las complicaciones tempranas y tardías, así como el diagnóstico de éstas mediante las diferentes técnicas de imagen permitirá un adecuado tratamiento, control post operatorio y disminución de la morbimortalidad.

Background: Preoperative anxiety is a frequent event that depends on multiple factors. One is the prior information to the patient, which must be simple, understandable and reliable. The aim of this study is to establish the relationship between the degree of information of the surgical procedure and the level of preoperative anxiety in patients scheduled for surgery. Material and methods: Cross-sectional study of 99 randomly selected patients scheduled for surgery at the Hospital Royo Villanova (sector I at Zaragoza). APAIS and STAI-AE scales were used to assess the preoperative anxiety level and the degree of prior information. The statistical analysis was performed using SPSS v.21.0, with the Chi-square test, ANOVA test and the nonparametric Kruskal Wallis to study the association between the different questions and the degree of anxiety. To assess the association of the two scales Pearson correlation test was used. Results: The educational level, type of surgery, previous surgery, specialty and previous surgery variables do not show statistical significance (p <0.05) compared to the anxiety level variable. It has been shown that there is an association between the degree of information and level of anxiety. Conclusions: The data shown in the present study support the hypothesis that patients who believe they need more knowledge about the surgical procedure have higher anxiety levels than patients who believe they need less.

Introducción: La ansiedad preoperatoria es un evento frecuente que depende de múltiples factores. Uno de ellos es la información previa que recibe el paciente, que debe de ser sencilla, inteligible y fidedigna. El objetivo de este estudio es establecer la relación entre el grado de información del procedimiento quirúrgico y el nivel de ansiedad preoperatoria en los pacientes programados para cirugía. Material y métodos: Estudio descriptivo transversal de 99 pacientes seleccionados aleatoriamente, programados para intervención quirúrgica en el Hospital Royo Villanova, del sector I de Zaragoza. Se valoró el nivel de ansiedad preoperatoria y el grado de información previa mediante la escala APAIS y se utilizó la escala STAI-AE en algunos de los pacientes, para comprobar la veracidad de la escala APAIS. El análisis estadístico se realizó mediante el programa SPSS v.21.0, aplicando la prueba de Chi-cuadrado, el test Anova y la prueba no paramétrica de Kruskal Wallis para estudiar la asociación entre las distintas preguntas y el grado de ansiedad. Para valorar la asociación de las dos escalas se empleó el test de Correlación de Pearson. Resultados: Las variables de: nivel educativo, tipo de cirugía, especialidad e intervención quirúrgica previa, no muestran una significación estadística (p<0,05) respecto a la variable de nivel de ansiedad. Se ha evidenciado que existe asociación entre el grado de información y el nivel de ansiedad. Conclusiones: Los datos que muestra el presente estudio refuerzan la hipótesis de que los pacientes que creen necesitar más conocimientos sobre el procedimiento quirúrgico presentan niveles de ansiedad mayores que los pacientes que creen necesitar menos.

The nutcracker esophagus, also known as corkscrew esophagus, describes the abnormally segmented appearance of the esophagus in cases of esophageal spasm, displayed in the double contrast study. Normally the primary peristalsis extends through the esophagus like a coordinated contraction and relaxation wave. In the esophageal spasm multiple segments contract simultaneously and there is an alteration of the normal relaxation. Symptoms include chest pain, dysphagia, or both.

El esófago en cascanueces, también conocido como esófago en sacacorchos, describe la apariencia anormalmente segmentada del esófago en los casos de espasmo esofágico, visualizada en el estudio con doble contraste. Normalmente el peristaltismo primario se extiende a través del esófago como una onda coordinada de contracción y relajación. En el espasmo esofágico múltiples segmentos se contraen simultáneamente y hay una alteración de la relajación normal. Los síntomas incluyen dolor en el pecho, disfagia o ambos.

The soils of Puchuncaví and Quintero, in the coastal area of central Chile, have been exposed to atmospheric deposition of sulfur dioxide (SO2) and metal-rich particles from the Ventanas Industrial Complex. The objective of this study was to determine, using geostatistical tools, the spatial distribution of copper and pH in these soils. Using Universal Kriging tool for geostatistical interpolation, we generated maps of continuous distribution of Cu and pH in the soils. The distribution of these variables was related to the distance from the industrial complex and to the direction of the winds. The concentrations of Cu and acidity were higher in the surroundings to the industrial complex and in the direction of the dominant winds. Although the distributions of both variables were similar, there was no correlation between the distribution of Cu and pH, which could be due to the distinct aerial dispersion dynamics of the compounds, which causes a divergence in their deposition on the soil. Specifically, this could be due to the fact that SO2 is smaller than the particulate matter that contains copper, so that it is capable of being dispersed over greater distances without being deposited on the soil.

Introduction: Dual-degree (DD) in oral and maxillofacial surgery still remains a controversial and/ or unsolved issue in many countries, although there is a growing trend towards its implementation in the developed world. The aim of this research is to describe the perceptions of Chilean oral and maxillofacial surgeons about DD and their position regarding the need of its implementation in Chile. Methodology: A cross-sectional survey was performed via the LimeSurvey web platform, included all surgeons registered in the Chilean Society. The questionnaire comprised two sections dedicated to surgical practice and perceptions about DD, respectively. Results: 67% (61) of surgeons completed the survey, main proportion men with more than 5 years of surgical practice, and experience in training teaching. 55.74% (34) considered the implementation of DD programs in Chile necessary. There are correlations between this pro-DD position and hospital practice, knowledge about DD, the need for more medical skills/knowledge in daily practice, the need for DD to perform the full scope of OMS, and the opinion that Chilean training programs are not practicing at an International level. Conclusion: In Chile, as in other countries, there is a dichotomic view of DD, and it appears absolutely possible to initiate a propositive discussion about it.

Introducción: El doble grado médico-dental (DG) en cirugía máxilofacial continúa siendo una cuestión controversial y sin resolver en muchos países, aunque hay una fuerte tendencia hacia su implementación en el mundo desarrollado. El objetivo de este trabajo es describir la percepción de los cirujanos máxilofaciales chilenos acerca del DG y su postura frente a la necesidad de implementarlo en el país. Metodología: Encuesta electrónica, realizada en la plataforma web LimeSurvey, incluyendo todos los cirujanos registrados en la Sociedad de Cirugía y Traumatología Bucal y Máxilofacial de Chile. El cuestionario incluyó 2 secciones: práctica quirúrgica y percepciones del DG. Resultados: 67% (61) cirujanos completaron la encuesta, la mayoría hombres, con más de 5 años de práctica quirúrgica y experiencia docente en la especialidad. 55,74% (34) consideran que la implementación de programas DG es necesaria en Chile. Hay asociación de la postura pro-DG y la práctica hospitalaria, conocimiento del doble grado, necesidad de mayores habilidades/conocimiento médico en la práctica diaria, necesidad del DG para practicar el campo completo de la especialidad y la opinión que los programas de especialización chilenos no están al nivel internacional. Conclusión: En Chile, como en otros países, hay una visión dicotómica del DG y parece perfectamente posible iniciar una discusión propositiva del tema.

A series of Bi2Mo xW1-xO6 catalysts supported on Al2O3-SiO2, SiO2-TiO2 and activated carbon (C*) were synthesized. The aim was to compare the different supports and calcination temperature of catalysts, studying their efficiency and activation temperature in the CO oxidation reaction. The catalysts active phase, Bi2Mo xW1-xO6, was made by means of chemical precipitation procedure starting from high purity (NH4)6Mo7O24•4H2O, (NH4)6W12O6•H2O, Bi(NO3)2•5H2O compounds, whichafterwards, were supported on Al(2)0(3)-Si02, Si0(2)-Ti0(2) and C* through impregnation. The catalysts characterization was carried out by means of X ray diffraction analysis (XRD), scanning electron microscopy (SEM) and surface area determination (BET method). Regarding the catalytic activity the Bi2Mo xWi-x0(6) /C* compound synthesized at 500 °C was the best catalyst being activated at 125 °C reaching 90 % conversion. It is concluded that was observed an effect of calcination temperature and the support on the different values reached for the catalytic activity.

Se preparó una serie de catalizadores de Bi2Mo xW1-xO6 soportados en Al2O3-SiO2, SiO2-TiO2 y carbón activado (C*). El propósito principal fue comparar el uso de diferentes soportes, así como también valorar el efecto de la temperatura de síntesis de los catalizadores en términos de su eficacia y de conversión en la reacción de oxidación de monóxido de carbono (CO) y en su temperatura de activación. La fase activa de los catalizadores, Bi2Mo xW1-xO6, se sintetizó a partir de los compuestos de alta pureza (NH4)6Mo7O24•4H2O, (NH4)6W12O6•H2O, Bi(NO3)2•5H2O, empleando el método de co-precipitación química, y posteriormente soportada por el método de impregnación en Al2O3-SiO2, SiO2-TiO2 ó C*. Estos sistemas catalizador/soporte se caracterizaron mediante las técnicas de difracción de rayos X (XRD), microscopía electrónica de barrido (SEM) y área superficial (método BET). Con respecto a la actividad catalítica, el compuesto con mayor eficacia en la conversión de CO a CO2 fue Bi2Mo xW1-xO6 /C*, que se preparó a 500 °C; se activó a 125 °C logrando una conversión de 90 %. Se concluye que existe un efecto de la temperatura de síntesis y del tipo de soporte que influye en los diferentes valores de actividad catalítica encontrados.