Abstract: Objective: to analyze the associations between breastfeeding duration and mixed feeding (breast milk and formula) with obesity, cardiometabolic risk (WHtR), body fat, and dietary and physical activity risk behaviors in children and adolescents. Subjects and Method: cross-sectional study carried out with 1,467 students in Costa Rica. An interview was conducted with parents and children to gather information on socioeconomic status, education, dietary and physical activity risk behaviors of the youth, including breastfeeding duration and mixed feeding. Body mass index, waist circumference, and body fat were assessed by bioelectrical impedance analysis and cardiometabolic risk was measured with the waist-to-height ratio (WHtR ≥ 0.5) by trained personnel. Descriptive statistics and logistic regression models were applied. Results: the average age was 11.4 ± 2.6 years and 50.9% were male. 55.5% of the population was middle class; 60% were sedentary, and 16% presented obesity. Around 20% were breastfed without the introduction of formula before 6 months, 13% were never breastfed, and more than 60% were breastfed for ≥ 6 months. Those children who were fed only with breast milk or in combination with formula for ≥ 6 months presented a lower percentage of obesity than those who received formula feeding only (60.8 vs 39.2; p < 0.005). Children with cardiometabolic risk (WHtR ≥ 0.50), unhealthy diet, sedentary lifestyle, and who were fed only with formula are at higher risk of developing obesity (OR = 18.8, 95% CI 13.2-26.0). Conclusions: these results are consistent with other studies and reinforce the evident protection of breastfeeding against the development of obesity.

Resumen: Objetivo: examinar la asociación entre la duración de la lactancia materna y la alimentación mixta con la obesidad, riesgo cardiometabólico, grasa corporal, conductas de riesgo dietéticas y de acti vidad física en niños y adolescentes. Sujetos y Método: estudio transversal en 1467 estudiantes de Costa Rica. Se aplicó una entrevista a padres e hijos para recopilar información socioeconómica, escolaridad, conductas de riesgo de la alimentación y actividad física de los jóvenes, duración de la lactancia materna y alimentación mixta. Se evaluó el índice de masa corporal, la circunferencia abdominal y la grasa corporal mediante análisis de bioimpedancia. El riesgo cardiometabólico se midió con el indicador cintura/talla (WHtR ≥ 0,5). Las mediciones fueron realizadas por personal estandarizado. Se aplicó estadística descriptiva y regresión logística. Resultados: la edad de los sujetos fue 11,4 ± 2,6 años; 50,9% hombres; 55,5% clase media; 60% sedentarios y 16% obesos. El 20% fue amamantado sin introducción de fórmula hasta los 6 meses y 13% nunca fue amamanta do; más del 60% fue amamantado por ≥ 6 meses. El porcentaje de obesidad de los que recibieron leche materna, sola o en combinación con fórmula, durante ≥ 6 meses fue menor que los que fueron alimentados solo con fórmula (60,8 vs 39,2; p < 0,005). Los niños con riesgo cardiometabólico, dieta no saludable, sedentarismo y que fueron alimentados sólo con fórmula, presentaron mayor riesgo de ser obesos (OR = 18,8, IC 95% 13,2-26,0). Conclusiones: estos resultados son consisten tes con otros estudios y refuerzan la protección evidente que tiene la lactancia materna frente al desarrollo de la obesidad.

Abstract: Introduction: Cystic fibrosis (CF) is a multisystemic disease, with high morbidity and mortality, and its early diagnosis improves results. Lung conditions are the main cause of morbidity and mortality and are closely related to nutritional status and survival. There is little national information about the liver and gastrointestinal characteristics in pediatric patients with CF. Objective: to describe at a gastrointestinal level, the general, nutritional, and genetic characteristics and the evolution of CF carriers with/without neonatal screening. Patients and Method: Retrospective study carried out in 4 public referral hospitals in the Metropolitan Region. The diagnosis of CF confirmed with two positive sweat tests (Gibson and Cooke method) was considered as an inclusion criterion. Those patients with unconfirmed neonatal screening tests through Immunoreactive Trypsinogen (IRT) or with only one positive sweat test were excluded. Sex, age, nutritional status, date of diagnosis, clinical presentation at the onset, evolution, and therapies received were recorded as clinical varia bles, and as laboratory ones, genetic study by means of a diagnostic panel with 36 mutations. The STATA 12 software was used for statistical analysis. Results: 127 patients were included. Respira tory manifestations (recurrent obstructive bronchial syndrome and pneumonia) were present in >60% and gastrointestinal ones (mainly malabsorption and malnutrition syndrome) in >80% of patients. On average, diagnostic confirmation took 4 months. The diagnosis guided by IRT was as sociated with better nutritional outcomes in the evolution of the patient. In 81.1% of the patients, the genetic study was performed. The most frequent mutations were those associated with DF508 (deletion of phenylalanine 508). 5.8% of the patients presented mutations not included in the gene panel used. Conclusions: Gastrointestinal CF appears with pancreatic, intestinal, and hepatic pathology throughout life. Malnutrition is a frequently present factor, which worsens the progno sis. The management of gastrointestinal manifestations and malnutrition are relevant to improve the morbidity and mortality of CF patients.

Resumen: Introducción: La fibrosis quística (FQ) es una enfermedad multisistémica, de alta morbimortalidad, cuyo diagnós tico precoz mejora los resultados. Las afecciones pulmonares son la principal causa de morbimortali dad y mantienen estrecha relación con el estado nutricional y la sobrevida. Existe escasa información nacional acerca de las características hepáticas y gastrointestinales en pacientes pediátricos con FQ. Objetivo: describir desde el punto de vista gastrointestinal, las características generales, nutricionales, genéticas y la evolución de pacientes portadores de FQ con/sin screening neonatal. Pacientes y Mé todo: Estudio retrospectivo en 4 centros hospitalarios públicos de referencia de la Región Metropo litana. Como criterio de inclusión se consideró el diagnóstico de FQ confirmado con 2 test de sudor positivos (método Gibson y Cooke). Se excluyeron aquellos pacientes con test de tamizaje neonatal mediante Tripsinógeno Inmuno Reactivo no confirmado o aquellos con sólo una prueba de sudor positivo. Se registraron variables clínicas, sexo, edad, estado nutricional, fecha del diagnóstico, pre sentación clínica al debut, evolución y terapias recibidas, y variables de laboratorio, estudio genético mediante panel diagnóstico con 36 mutaciones. Para el análisis estadístico se utilizó el programa STATA 12. Resultados: Se incluyeron 127 pacientes. Las manifestaciones respiratorias (síndrome bronquial obstructivo recurrente y neumonía) estuvieron presentes en >60% y las gastrointestinales (principalmente síndrome de malabsorción y desnutrición) en >80% de los pacientes. En prome dio, la confirmación diagnóstica demoró 4 meses. El diagnóstico guiado por Tripsinógeno Inmuno Reactivo (IRT) se asoció a mejor resultado nutricional en la evolución. En 81,1% de los pacientes se realizó el estudio genético. Las mutaciones más frecuentes fueron las asociadas a DF508 (deleción de fenilalanina en la posición 508). El 5,8% de los pacientes presentaron mutaciones no incluidas en el panel de genes utilizado. Conclusiones: La FQ gastrointestinal se manifiesta con patología pancreá tica, intestinal y hepática a lo largo de la vida. La desnutrición es un factor presente frecuentemente, que empeora el pronóstico. El manejo de las manifestaciones gastrointestinales y la desnutrición son relevantes para mejorar la morbimortalidad de los pacientes con FQ.

RESUMO: A sorção de pesticidas no solo é o principal fator responsável por regular o destino de pesticidas no ambiente, afetando a degradação microbiológica e química, volatilização e lixiviação. O principal objetivo deste trabalho foi estudar o efeito da fase orgânica de solos vulcânicos sobre a sorção de pesticidas agrícolas. A sorção e dessorção de oito solos vulcânicos cujos constituintes flúvico e húmico de sua matéria orgânica eram variáveis. Os resultados mostraram que, para todos os pesticidas, a sorção foi bem descrita por uma isoterma de Freundlich, e os valores 1/nads indicam que o mecanismo de sorção poderia ser explicado principalmente por reações físicas em todos os solos. Carbaryl e flumioxazin foram mais adsorvidos, com Kf média de 7,78 e 7,16 mL g-1, enquanto hexazinone e metsulfuron-methyl foram os pesticidas mais lábeis, com Kf de 0,86 e 0,81 mL g-1, respectivamente. A fração orgânica do solo foi o principal fator relacionado à sorção de todos os pesticidas estudados. Especificamente, o teor de ácido húmico regulou a atração entre o pesticida e o solo, principalmente através dos grupos carboxílicos.

ABSTRACT: Pesticide soil sorption is a primary factor that influences the fate of pesticides in the environment, affecting regulation of microbiological and chemical degradation, volatilization and leaching. The main goal of this research was to study the effect of the organic phase of volcanic soils on sorption of agricultural pesticides. Sorption and desorption of eight agricultural pesticides were studied on eight volcanic soils that varied in the fulvic and humic constituents of their organic matter. For all pesticides, sorption was well described by a Freundlich isotherm where 1/nads values indicated that the sorption mechanism could be mainly explained by physical reactions in all soils. Kf values for carbaryl and flumioxazin were the highest with average values of 7.78 and 7.16 mL g-1, respectively. By contrast, hexazinone and metsulfuron-methyl had the lowest average Kf: 0.86 and 0.81 mL g-1, respectively, indicating that they were the least attracted to the soils. The organic fraction of the soil was the main soil factor related to the sorption of all study pesticides. Particularly, humic acid content regulated the sorption between pesticide and soil, especially through the carboxylic groups.

Abstract Background: Endophytic fungi are diverse and ubiquitous in nature, yet studies simultaneously comparing endophyte communities in above- and below-ground plant tissues are relatively scarce. The main goal of our study was to compare the diversity and community composition of endophytic fungi associated with above- and below-ground tissues of the plant Aristolochia chilensis in an arid ecosystem. Endophytic fungi were isolated from healthy leaves and roots of A. chilensis , and the internal transcribed spacer (ITS) region was sequenced for phylogenetic and taxonomic analysis. Results: A combined total of 457 fungal isolates were cultured from leaf and root tissues, belonging to 54 operational taxonomic units (OTUs). The genera Fusarium, Penicillium, Phialemonium and Trichoderma were the most representative endophyte taxa identified in A. chilensis tissues; nevertheless, Fusarium was significantly more dominant in the below-ground community, while foliar endophyte community was dominated by Penicillium. Whereas OTU richness and diversity were not different between below-ground and above-ground tissues, endophyte abundance was on average twice as high in below-ground tissue than in above-ground tissue. Fungal endophyte communities in the two tissue types were significantly dissimilar. Conclusions: Results from this study indicate that A. chilensis harbors a similar diversity of endophytic fungi in above- and below-ground tissues. Dominant endophytic fungi were found to be dependent on tissue type, which potentially resulted in marked differences in community structure between above- and below-ground tissues. Ecological processes potentially affecting this pattern are discussed.

Introduction: Postoperative liver failure (POLF) is a relevant cause of morbimortality after liver surgery. An insufficient future liver remnant (FLR) is one of the main causes of POLF. The association of hepatic bipartition with portal ligation for 2-stage hepatectomy (ALPPS) is a relatively new technique that induces rapid parenchymal hypertrophy reducing the waiting time to achieve adequate FLR. Our aim is to communicate the experience and the initial results of the hepatectomy in 2-stages using the ALLPS technique. Material and Method: All patients in whom a 2-stage hepatectomy using ALPPS technique between June 1, 2014 and July 31, 2016 in the Digestive Surgery Unit of the Hospital Regional of Talca were included. Results: There were 47 hepatectomies performed at the Hospital Regional of Talca. In 3 cases (6.3%), a 2-stage hepatectomy was performed using the ALPPS technique, in all of which a hypertrophy of the future hepatic remnant (RHF) was achieved, which allowed completing the second stage without POLF clinically significant. Conclusion: In our initial experience, the ALPPS technique successfully allowed increase FLR in patients who initially had insufficient FLR to be submitted a major liver resection.

Resumen Introducción: La insuficiencia hepática posoperatoria (IHP) es una causa importante de morbimortalidad posoperatoria en cirugía hepática. Un remanente hepático futuro (RHF) insuficiente es una de las principales causas IHP La asociación de bipartición hepática con ligadura portal para hepatectomía en 2 tiempos (ALPPS) es una técnica relativamente nueva que induce una rápida hipertrofia parenquimatosa reduciendo el tiempo de espera para lograr un volumen hepático adecuado. Nuestro objetivo es comunicar la experiencia y los resultados iniciales de la hepatectomía en 2 tiempos utilizando la técnica de ALLPS. Material y Método: Se incluyeron todos los pacientes en los que se ha realizado una hepatectomía en 2 tiempos utilizando la técnica de ALPPS entre el 1 de junio de 2014 y el 31 de julio de 2016 en la Unidad de Cirugía Digestiva del Hospital Regional de Talca. Resutados: Durante el periodo de estudio, se realizaron 47 hepatectomías en el Hospital Regional de Talca. En 3 casos (6.3%), se realizó una hepatectomía en 2 tiempos utilizando la técnica de ALPPS, en todos ellos se logró una hipertrofia del remanente hepático futuro (RHF) que permitió completar el segundo tiempo sin IHP clínicamente significativa. Conclusión: En nuestra experiencia inicial, la técnica de ALPPS logró aumentar el RHF permitiendo resecar pacientes que inicialmente tenían un RHF insuficiente para ser sometidos a una hepatectomía mayor.

Abstract: Introduction: Tumors of salivary glands are uncommon and comprise of about 5% of all head and neck tumors. Although constituting less than 15% of all salivary gland tumors, mucoepidermoid carcinoma account for approximately 30% of all malignant salivary gland neoplasms. Commonly these tumours are metastatic to local lymph nodes and distant metastases are rare (especially, in low and intermediate grade tumors). Case report: We report a case of 65 years old man who developed peritoneal carcinomatosis secondary to metastatic dissemination of mucoepidermoid carcinoma of the major salivary glands, which is an uncommon occurrence with intermediate grade tumors.

Resumen: Introducción: Los tumores de glándulas salivales son neoplasias poco frecuentes y representan menos del 5% de todos los tumores de cabeza y cuello. El carcinoma mucoepidermoide representa un 10-15% de todas las neoplasias de las glándulas salivales y aproximadamente un 30% de los tumores malignos salivales. El comportamiento biológico y las manifestaciones clínicas de este tipo de tumores son variables y se correlacionan con el estadio y grado histológico, siendo la presencia de metástasis a distancia un hallazgo inhabitual (en especial, en tumores de grado bajo o intermedio). Caso clínico: Paciente de 65 anos de edad con antecedentes de tabaquismo, a quien se diag nostica carcinoma mucoepidermoide de grado intermedio de glándula submandibular izquierda tratado con cirugía más radioterapia adyuvante, y que presenta progresión metastásica hepática y carcinomatosis peritoneal a los 26 meses de seguimiento.

ABSTRACT At the Valley of Lluta, XV Region of Arica and Parinacota, Chile, the cultivation of lettuce (Lactuca sativa L.) cv. del río, evidences significant differences in several factors: crop yields, plant weight, polar and equatorial diameters, nitrate and boron content; as well as damages induced by high concentration levels of salts and boron, naturally present in the water and cultivation soil of this valley. Here, are informed the results of a mitigation study of boron induced damages on a cultivation of lettuce (Lactuca sativa L.) cv. del río en el valle de Lluta, using amendments of stabilized cow manure as a mitigating agent; including a witness cultivation subplot, without cow manure amendment and three cultivation subplots differentiated with 25 kg, 50 kg and 100 kg of cow manure amendments.The uses of the stabilized cow manure in the cultivation of lettuce cv del rio, yielded a significant increase in the content of organic matter in the cultivation soil and a moderate subsiding of the damages induced by the high boron and salt contents on the lettuce plants.

RESUMEN En el valle de Lluta, XV Región de Arica y Parinacota, Chile, el cultivo de lechuga (Lactuca sativa L.) cv. del río, evidencia diferencias significativas en varios factores: rendimientos, peso de las plantas, diámetros polar y ecuatorial, contenidos de nitrato y boro en las hojas; así como el daño inducido por la interacción de sales y boro, naturalmente presentes en altas concentraciones en el agua y suelos de este valle. A continuación, se informan los resultados de un estudio de mitigación de los daños inducidos por boro sobre un cultivo de lechuga (Lactuca sativa L.) cv. del río en el valle de Lluta, usando estiércol de vacuno estabilizado como agente mitigador; incluyendo un cultivo testigo, sin enmienda de estiércol y tres cultivos diferenciados con 25 kg, 50 kg y 100 kg de enmienda de estiércol de vacuno. El uso de estiércol de vacuno estabilizado en el cultivo de lechuga cv del río, produjo un significativo incremento del contenido de materia orgánica en el suelo de cultivo y una significativa aunque moderada disminución del daño inducido por los altos contenidos de boro y sales sobre las plantas de lechuga.

El reglamento de etiquetado nutricional para alimentos preenvasados de Costa Rica basado en la normativa del Codex Alimentarius entró en vigencia en el 2002. En este mismo año, se realizó una investigación con el propósito de describir la situación basal del etiquetado nutricional en estos alimentos. En un supermercado representativo del área metropolitana de Costa Rica se recolectó la información declarada en las etiquetas de todos los alimentos preenvasados, excepto de las bebidas alcohólicas. Se analizaron seis variables mediante el programa SPSS. Se revisaron 2.910 etiquetas de alimentos clasificados en 19 categorías. El 58,4% (n=1698) incluyó información nutricional, dato que varió según país de origen y categoría del alimento. De las etiquetas con información nutricional, 68,1% declararon el contenido nutricional, 1,2% descriptores nutricionales y 27,4% ambos. En el 95% del etiquetado nutricional se declaró el contenido de energía y macronutrientes. Se identificaron al menos 100 descriptores nutricionales y saludables diferentes, con mayor frecuencia se empleó el de contenido (74,7%), seguido por el de adición (16,9%). Los componentes referidos con mayor frecuencia fueron vitaminas y minerales, vitaminas, carbohidratos, grasa total, colesterol y energía; y los grupos de alimentos que los declararon fueron: cereales y derivados, alimentos infantiles, leches, bebidas, alimentos para regímenes especiales y sustitutos. En una misma etiqueta fueron declarados entre uno y cinco descriptores. En una década en Costa Rica se triplicó la proporción de alimentos preenvasados con etiquetado nutricional, por lo se concluye que la tendencia de su declaración es ascendente, sostenida y representa una herramienta accesible para la promoción de la salud en la población, siempre y cuando la información sea confiable y segura.

The nutritional labeling regulations for prepackaged foods based on the Codex Alimentarius legislation enacted in 2002 in Costa Rica. In the same year, a research was conducted in order to describe the baseline of nutritional labeling. The declared information on the labels of all prepackaged foods was collected, except for alcoholic beverages. Six variables were analyzed using SPSS. 2,910 labels of foods were reviewed and classified in 19 food categories. 58.4% (n= 1698) included nutritional information, proportion that varied by country of origin and food category. Of the labels that included nutritional information, 68.1% had nutritional panel, 1.2% nutrient claims and 27.4%, both. 95% of the nutritional components declared on the labels included energy and macronutrients data. At least 100 different nutritional and health claims were identified. Most frequently used claims were content (74.7%), followed by addition (16.9%). The components most frequently mentioned were vitamins and minerals, vitamins (alone), carbohydrates, total fat, cholesterol and energy. Food groups who reported these descriptors were: cereals and by products, baby foods, milks, beverages, foods for special dietary uses and substitutes. One to five descriptors were used in a label. In a decade the proportion of prepackaged foods with nutritional labeling tripled in the metropolitan area of Costa Rica. It is concluded that the tendency of nutrition information declaration is up, sustained and represents an accessible tool for health promotion, if the information provided is reliable and secure.

El presente artículo sistematiza, brevemente, algunos de los principales aportes en la construcción del enfoque de la Nueva Gestión Pública (Hood, Barzelay, Olías de Lima, CLAD y OCDE). Desde allí se hace un breve recorrido por las reformas vividas en la Administración Pública Chilena bajo los gobiernos democráticos, desde 1990 a la fecha, con especial énfasis en sus componentes estratégicos y en las transformaciones de alto valor público y consecuentemente de esperado alto impacto. A partir de una propuesta metodológica ad hoc, que considera pautas de comparación, se revisan las influencias que las orientaciones de la Nueva Gestión Pública, han tenido en el sector público chileno. Finalmente, a modo de conclusión, se hace un repaso por algunos elementos del contexto sociopolítico chileno que empujan a encontrar fórmulas diferentes y se establecen algunas conclusiones respecto de la validez global del modelo.

This present article briefly systematizes some of the principal contributions about the construction from the of the New Public Management approach (Hood, Barzelay, You Were Smelling of Lima, CLAD and OECD). Based upon this brief review, this study looks at the reforms on the Public Chilean Administration which were undertaken over the democratic governments, beginning in 1990 until now, making special emphasis on those transformations with strategic components, high public value and expected high impact. Having established an ad hoc methodological proposal, which considers two evaluation approaches, the influence of the New Public Management on the Chilean Public Sector is then revised. Finally, as a conclusion, some elements of the Chilean sociopolitical context which contribute to find different solutions are revised and some conclusion are presented regarding the applicability of this model.

Justificación: La obesidad se considera un problema de salud pública. La encuesta directa es el método más utilizado para generar información al respecto, pero su alto costo económico limita obtener datos periódicos. Se han experimentado otros métodos de recolección de información; entre ellos la encuesta telefónica se concibe como una opción válida de costo menor. Objetivo: Explorar la percepción del peso corporal de adultos costarricenses y las estrategias utilizadas para controlarlo, mediante el análisis de la información obtenida en la primera Encuesta Telefónica de Salud del IDESPO. Métodos: Estudio descriptivo, transversal. Se elaboraron preguntas abiertas sobre conocimiento, percepción y estrategias sobre peso corporal, que se incorporaron en la primera Encuesta Telefónica de Salud del IDESPO. Resultados: El 50,3% y 42% de los sujetos se percibieron con peso normal y peso alto o muy alto, respectivamente. Las principales estrategias para perder el peso: hacer ejercicio (29,4%), cambios en la alimentación; 42% de los hombres y 44% de las mujeres reportaron "no hacer nada". Al contrastar la percepción del peso con el IMC estimado, más del 25% de mujeres y 34% de hombres que se percibieron con peso normal presentaron sobrepeso. Conclusiones: La metodología de encuesta telefónica introduce una subestimación en la per- cepción del exceso de peso conforme avanza la edad. La encuesta telefónica no sustituye las encuestas directas, pero se visualiza como alternativa para generar información sobre factores de riesgo cardiovascular. El reto próximo será validarla en nuestro contexto.

Rationale: Obesity is considered a public-health problem. A direct survey is the method most-frequently used to generate relevant information but its high economic cost doesn´t allow obtaining periodic data. Other methods of collecting information have been tried and, among these, the telephone survey is seen as a valid option at lower cost. Objective: To explore the perception of body-weight among Costa Rican adults as well as the strategies used to control this variable by analyzing information obtained in the First Telephone Health Survey conducted by IDESPO (The Institute for Social Studies in Populations.) Methods: a cross-sectional, descriptive study was carried out. Open questions were developed having to do with knowledge, perception and strategies to deal with body-weight. These were incorporated into the Health Survey mentioned above. Results: 50.3 % and 42% of the subjects, respectively, had a self-perception of normal weight or of high - very high weight. The main weight-loss strategies were: doing exercise (29.4%), changes in diet and no special strategy (the latter as admitted by 42% of men and 44% of women). When comparison of self-perception of weight with estimated BMI was done, more than 25% of females and more than 34% of males of those thinking they had normal weight were actually overweight. Conclusions: a telephone-survey methodology introduces an underestimate in the self-perception of overweight according to age. While telephone surveys do not substitute direct surveys, they can be seen an an alternative to generate information about cardiovascular risk factors. The next challenge will to validate these surveys in Costa Rica.

Calibration of mechanistic kinetic models describing microorganism growth and secondary metabolite production on solid substrates is difficult due to model complexity given the sheer number of parameters needing to be estimated and violation of standard conditions of numerical regularity. We show how advanced non-linear programming techniques can be applied to achieve fast and reliable calibration of a complex kinetic model describing growth of Gibberella fujikuroi and production of gibberellic acid on an inert solid support in glass columns. Experimental culture data was obtained under different temperature and water activity conditions. Model differential equations were discretized using orthogonal collocations on finite elements while model calibration was formulated as a simultaneous solution/optimization problem. A special purpose optimization code (IPOPT) was used to solve the resulting large-scale non-linear program. Convergence proved much faster and a better fitting model was achieved in comparison with the standard sequential solution/optimization approach. Furthermore, statistical analysis showed that most parameter estimates were reliable and accurate

The frequency of Crohn disease shows a significant increase in the last century. Affected patients show a misbalance between production of free radicals and anti oxidant defenses. Thus, one of the increasingly accepted htypotheses to explain the origin of this disease, is the oxidative stress that occurs in the intestinal mucosa. Dietary factors including self administered vitamin and mineral supplemets may play a role, especially when they contain excessive amounts of iron and copper, known for their prooxidant capacities. Unfortunately, little is known about how these metals may influence the antioxidant defenses in the intestinal mucosa. This article reviews the literature on the why and how these elements may act on individuals susceptible to develop Crohm disease, including the evidence supporting the hypothesis that oxidative stress in the intestinal mucosa is an important pathogenetic factor

The objective of this study was to assess the effect of a GABA receptor antagonist, (Bicuculline) on the pulsatile LH secretion before, during and after fasting in ewe lambs. Five Suffolk ewe lambs of 20 weeks of age were subjected to fasting for 8 days. A study of LH pulsatility was performed before (day 0), after one and eight days of fasting and 48 hours after the end of fasting. This study consisted in collecting blood samples by means of an indwelling jugular vein catheter at 10 min intervals for 10 hours from 9am inwards hours. Five hours after the start of the pulsatility study, a bolus of Bicuculline (50 ug/kg BW) was given intravenously. Thus, the 10-hours study period was divided in two phases of 5-hours each: before and after bicuculline. Parameters of the LH secretion were determined by the CLUSTER program independently for both phases and compared by paired t-test. Basal parameters of LH secretion on each day of the study were analyzed with ANOVA for repeated measures and comparison of the means with the Newman Keuls’s test. Body weight was recorded and basal levels of blood glucose, insulin and cortisol were also obtained before, during and after fasting. Body weight and basal plasma glucose concentrations decreased significantly after 8 days of fasting, however, insulin and cortisol did not change. Parameters of pulsatile LH secretion did not change with fasting or after 48 hours of refeeding. Bicuculline tended to increase (p<0.06) both mean plasma concentrations and amplitude of LH pulses before fasting (Day 0), but it had no effect on LH secretion on day 1, 8 of fasting or after two days of refeeding. Results suggest that GABA may be involved in the control of LH secretion in normally fed ewe lambs, however this control is not apparent during fasting. Fasting has an impact on body weight and plasma glucose concentrations but no effect on basal plasma levels of insulin. Plasma cortisol concentrations did not change suggesting that fasting did not evoke a stress condition.

El propósito de este estudio fue establecer si la actividad gabaérgica forma parte de los mecanismos supresores de la secreción pulsátil de LH durante el ayuno en ovejas prepúberes. 5 borregas Suffolk de 20 semanas de edad fueron sometidas a un ayuno de 8 días. Se recolectaron muestras de sangre mediante un cáteter endovenoso para medir en su plasma las concentraciones de LH, un día antes del comienzo del ayuno (día 0), el primer día de ayuno (día 1), el ultimo día del ayuno (día 8) y 48 horas finalizado éste (día 10), cada 10 minutos, por cinco horas. Al término de las primeras 5 horas de muestreo se administró un pulso de bicuculina (50 ug/kg PV), un antagonista de receptores GABA-A, y se continuó el muestreo sanguíneo por otras cinco horas. Las características de la secreción pulsátil de LH se determinaron con el programa computacional Cluster. Se compararon las características de secreción de LH antes y después de la administración de bicuculina en los 4 días del ensayo empleando un test de t pareado para comparar entre períodos y Andeva para comparar entre días del ensayo. El peso vivo y las concentraciones plasmáticas basales de glucosa disminuyeron con el ayuno, mientras que las concentraciones plasmáticas de insulina y cortisol se mantuvieron sin cambios. El peso vivo y la glucosa plasmática se recuperaron significativamente con la realimentación. La administración de un pulso de Bicuculina tendió a aumentar la concentración plasmática promedio y la amplitud de los pulsos (p<0.07) de LH, mientras que la frecuencia de pulsos y el nadir no cambiaron (p0.05)antes delayuno (día 0). Por el contrario, la administración de bicuculina no tuvo efecto sobre estos parámetros de secreción de LH durante los días 1, 8 y 10 del ensayo (p0.05). Los resultados sugieren que las vías GABAérgicas participarían en el control de la secreción de LH en ovejas prepúberes con alimentación normal, situación que no es demostrable durante el ayuno. La ausencia de cambios en las concentraciones basales de cortisol sugieren que el ayuno no activa reacciones de stress.

Background: Few trials have studied the prevalence of sexual dysfunction (SD) and related risk factors in postmenopausal women using the DSM-IV criteria. Aim: To evaluate the prevalence of SD in menopausal women and the impact of risk factors. Patients and methods: Five hundred thirty four healthy women, 40 to 64 years of age were interviewed using the Laumann test (DSM-IV). Results: Mean age was 52.4±5.7 years. Eighty three percent were peri or postmenopausal, 23% used hormonal substitution therapy and 79.2% were sexually active. Among sexually active women, the prevalence of SD increased along with age, from 22.2% at the 40-44 years old range to 66.0% in the 60-64 years old group. Hormone users and healthy women had a low risk for SD (Odds ratio (OR): 0.1 IC: 0.0-0.1 and OR: 0.6 IC: 0.3-0.9, respectively). The risk increased in menopausal women (OR: 3.3 IC: 1.6-6.9), those older than 49 years (OR: 3.4 IC: 1.8-6.4), those subjected to hysterectomy (OR: 3.7 IC: 1.3-10.6) or those with an impotent sexual partner (OR: 3.2 IC: 1.2-8.6). Conclusions: There is a high prevalence of SD among climacteric women. Estrogens, either endogenous or exogenous, have a positive influence on sexuality (Rev Méd Chile 2002; 130: 1131-8)