Las hormonas femeninas en fisiología renal: Sensibilidad a la sal y regulación de la proliferación epitelial / Female hormones in renal physiology. Salt sensitivity and regulation of epithelial proliferation

Un tercio de la población mundial tiene niveles anormalmente altos de presión arterial, hipertensión, responsable de casi el 50% de las muertes por accidente cerebrovascular y enfermedad coronaria. La sensibilidad a la sal es un factor de riesgo para la morbilidad y mortalidad cardiovascular y también para otras enfermedades. En estudios previos describimos un modelo de hipertensión sal sensible (HSS) en ratas Wistar ovariectomizadas (oVx) adultas. Las ratas oVx son normotensas con ingesta normal de sal (NS, 0.24% de NaCl), pero desarrollan un perfil de HSS con una ingesta elevada de sal (HS, 1% de NaCl). En los estudios en riñón encontramos que el circuito receptor D1 de dopamina, citocromo P450 4A y Na+, K+-ATPasa está alterado por la ausencia de hormonas ováricas, lo que se asocia a menor excreción de sodio e hipertensión arterial. La ingesta HS en ratas oVx también promueve cambios en la expresión de proteínas relacionadas con el transporte de sodio en células mononucleares de sangre periférica, principalmente linfocitos periféricos. Por lo tanto, el transporte de sodio se modifica en varios niveles de la fisiología normal. En estudios recientes observamos que el estradiol aumenta la proliferación y diferenciación de células epiteliales en cultivos de corteza renal humana. Sensibilidad a la sal, inmunidad adaptativa, presión arterial y proliferación de células epiteliales en riñón son fenómenos de gran importancia biológica regulados por estradiol.

Female sex hormones participate in the regulation of blood pressure and renal epithelial proliferation, effects not related to their reproductive function. About one-third of the world's population has abnormally high levels of blood pressure, hypertension, which is responsible for almost 50% of deaths from stroke and coronary heart disease. Salt sensitivity is a risk factor for cardiovascular morbidity and mortality and other diseases as well. We reported a model of salt sensitive hypertension in adult ovariectomized (oVx) Wistar rats. oVx rats are normotensive under normal salt intake (NS, 0.24% NaCl), but upon a high salt intake (HS, 1% NaCl) oVx rats developed a blood pressure profile of salt-sensitive hypertension. Our studies on kidney molecules related to sodium balance found that the circuit dopamine D1-like receptor, cytochrome P450 4A and Na+, K+-ATPase is altered by the absence of ovary hormones which is accompanied by a reduced ability to excrete sodium. In oVx rats HS intake also promotes changes in the expression of proteins related to sodium transport in peripheral blood mononuclear cells, mainly peripheral lymphocytes. Therefore, sodium transport is modified at several levels of normal physiology. Lately, we described that estradiol increases the rate of renal epithelial cell proliferation in primary cultures developed from human renal cortex. Thus, salt sensitivity, adaptive immunity, blood pressure and renal cell proliferation are complex biological responses regulated by female sex hormones.

Sal y Salud: conocimientos y percepción de riesgo según jóvenes y profesionales de la salud / Salt and health: knowledge and risk perception according to young people and health professionals

Las técnicas cualitativas permiten comprender una porción de la realidad tal como la perciben y escriben sus actores. Objetivos: 1) Identificar en jóvenes de 21 a 30 años conocimientos sobre sal, impacto en el organismo, cantidad diaria recomendada y percepción de riesgo al superarla. 2) Conocer a través de profesionales de la Salud conocimientos y percepciones en las poblaciones por ellos asistidas. Materiales y Método: Estudio cualitativo mediante entrevistas en profundidad a 7 jóvenes y 4 profesionales (médico cardiólogo hipertensólogo, médico pediatra, licenciada en nutrición y médico generalista). Resultados: Profesionales: predominaron consultas por sintomatología o evento patológico; las mujeres tenían más prácticas preventivas que los hombres; las personas desconocían el impacto de la sal en el organismo (salvo ante antecedentes patológicos propios o de conocidos) y el contenido de sodio de alimentos y productos alimenticios; la resistencia al cambio de hábito se debía a gusto, estilos de vida y situaciones sociales; los circuitos del sistema de salud, educativo, clubes y medios masivos de comunicación podrían difundir recomendaciones de sociedades científicas; la industria alimentaria debería ofrecer productos bajos en sodio sin aumentar su costo. Jóvenes: incluyeron en el cuidado de la salud “una dieta sana”, asociada con comer alimentos variados, más frutas y verduras y menos frituras sin mencionar la sal; asociaron ingesta de sal con efectos nocivos para el organismo sin ser tema de preocupación; reconocieron resistencia a cambiar hábitos; no conocían la cantidad diaria recomendada (5-6 g de NaCl) ni su traducción a elecciones alimentarias; sugirieron acciones educativas a través de redes sociales. Conclusiones: No se encontraron conocimientos sobre cantidad diaria recomendada de sal, percepción de riesgo de ingesta excesiva de sodio ni medidas preventivas...

Consumo de sódio em uma unidade de alimentação e nutrição de Belo Horizonte, MG / Sodium consumption in a food and nutrition unit of Belo Horizonte, MG

Este trabalho teve como objetivo avaliar as quantidades de sódio nas preparações e nas fichas técnicas de preparo de uma unidade de alimentação e nutrição industrial cadastrada pelo Programa de Alimentação do Trabalhador do município de Belo Horizonte, Minas Gerais. Caracterizou-se como um estudo transversal sobre a avaliação quantitativa do consumo de sódio utilizado nas preparações e nas Fichas Técnicas de Preparo de uma Unidade de Alimentação e Nutrição industrial. Dos cardápios de 20 dias analisados, apenas em um dia, a quantidade per capita de sódio ficou abaixo do valor máximo de sódio recomendado pelo Programa de Alimentação do Trabalhador, 960mg para as grandes refeições. Considerando que os usuários desta unidade de alimentação realizam suas refeições diariamente neste local, existe uma grande possibilidade dos mesmos apresentarem hipertensão arterial, ressaltando a importância do papel do nutricionista na elaboração de cardápios, visando alcançar as recomendações do Programa de Alimentação do Trabalhador e, principalmente, a promoção da saúde dos usuários desta unidade.

Development of Advanced Atherosclerotic Plaque by Injection of Inflammatory Proteins in a Rabbit Iliac Artery Model

PURPOSE: Appropriate animal models of atherosclerotic plaque are crucial to investigating the pathophysiology of atherosclerosis, as well as for the evaluation of the efficacy and safety of vascular devices. We aimed to develop a novel animal model that would be suitable for the study of advanced atherosclerotic lesions in vivo. MATERIALS AND METHODS: Atherosclerotic plaque was induced in 24 iliac arteries from 12 rabbits by combining a high cholesterol diet, endothelial denudation, and injection into the vessel wall with either saline (n=5), olive oil (n=6), or inflammatory proteins [n=13, high-mobility group protein B1 (HMGB1) n=8 and tumor necrosis factor (TNF)-α n=5] using a Cricket™ Micro-infusion catheter. Optical coherence tomography (OCT) was performed to detect plaque characteristics after 4 weeks, and all tissues were harvested for histological evaluation. RESULTS: Advanced plaque was more frequently observed in the group injected with inflammatory proteins. Macrophage infiltration was present to a higher degree in the HMGB1 and TNF-α groups, compared to the oil or saline group (82.1±5.1% and 94.6±2.2% compared to 49.6±14.0% and 46.5±9.6%, p-value<0.001), using RAM11 antibody staining. On OCT, lipid rich plaques were more frequently detected in the inflammatory protein group [saline group: 2/5 (40%), oil group: 3/5 (50%), HMGB1 group: 6/8 (75%), and TNF-α group: 5/5 (100%)]. CONCLUSION: These data indicate that this rabbit model of atherosclerotic lesion formation via direct injection of pro-inflammatory proteins into the vessel wall is useful for in vivo studies investigating atherosclerosis.

Etiquetado nutricional, ¿qué se sabe del contenido de sodio en los alimentos? / Nutritional labelling, what is known about the sodium content in foods?

La ingesta excesiva de sodio es una característica de nuestra alimentación, es un factor de riesgo de hipertensión arterial y de muerte por complicaciones cardiovasculares. Los alimentos procesados aportan el mayor contenido de sodio en la dieta y su cantidad aparece en las etiquetas de los envases. Este estudio fue diseñado para conocer si los consumidores leen y entienden la información relacionada con el contenido de sodio anotado en las etiquetas, si tienen conocimiento de la relación sodio-sal, de la cantidad máxima de sal reco-mendada para el consumo diario y si obtienen información relacionada en la consulta médica. MATERIAL Y MÉTODO Estudio descriptivo transversal de los resultados de una encuesta realizada a adultos mayores de 19 años en la sala de espera de las consultas de Medicina Interna Adulto y Pediatra en Clínica Las Condes en el período 2012. RESULTADOS 308 (89,2%) de un total de 345 encuestas fueron respondidas correctamente. 93,8% de las mujeres y 80,0% de los hombres (p<0,001) se preocupan por una alimenta-ción saludable, 70,4% refirió conocer la diferencia entre sodio y sal. 39,8% reconoció leer siempre las etiquetas, 52,2% sólo a veces y 8% nunca. El mayor grado de conocimiento referido por los encuestados fueron aquellos que reportaron leer las etiquetas, con una diferencia significativa con aquellos que reportaron no leer las etiquetas (p=0,001). 30,5% de las mujeres y 28,6% de los hombres sabía cuál era la cantidad de sal aconsejada para el consumo diario. El 53,3% no ha re-cibido información médica acerca de la importancia del sodio en la dieta. CONCLUSIÓN La mayoría de los encuestados manifestó su interés por una alimentación sana. Sin embargo, sólo una minoría refirió leer las etiquetas, conocer la cantidad de sal diaria recomendada y recibir información sobre la importancia del sodio en la alimentación.

Excessive sodium intake is a risk factor for hypertension and cardiovascular death. Processed foods provide the highest sodium content in the diet and the amount is shown on the package labels. The aim of this study was to know if consumers read and understand the information related to sodium listed on the labels, are aware about the relation between sodium and salt, know the maximum amount of salt recommended for daily consumption and if they receive medical advice about the importance of dietary sodium intake. MATERIAL AND METHOD A descriptive cross-sectional study was performed. The information was collected through a survey given to adults older than 19 years old in the waiting room consultations of internal medicine and pediatrics at Clínica Las Condes during 2012. RESULTS 308 (89,2%) of a total of 345 surveys were answered completely. 93,8% of women and 80,0% of men (p<0,001) care about healthy eating, 70,4% reported knowing the difference between sodium and salt. 39,8% referred to read always the labels, 52,2% only sometimes and 8% never. The highest degree of knowledge referred by respondents were those who reported reading labels, with a significant difference to those who reported not reading labels. (p=0,001). 30,5% of women and 28,6% of men were aware about the recommended dietary salt intake. 53,3% reported not receiving professional advice about the relevance of sodium in the diet. CONCLUSION Most of the respondents expressed their interest in healthy eating. However, only a minority referred to read the labels, to know the daily recommended dietary salt intake and to receive information about the importance of sodium in the diet.

Sal y salud: avances en conocimientos, acciones y propuestas / Salt and health: progess in knowledge, actions and proposals / Sal e saúde: avanços em conhecimentos, ações e propostas

En la Argentina y el mundo existen acciones tendientes a reducir la ingesta de sal; entre ellas, intervenciones de educación al consumidor y reducción del contenido de sal en alimentos procesados. Las Guías Alimentarias parala Población Argentina editadas en 2000 incluyen un mensaje específico destinado a orientar una ingesta que no supere los 6g diarios. El Foro de la Organización Mundial de la Salud s obre la Reducción del Consumo de Sal enla Población recomienda educar al consumidor y promover entornos que faciliten la elección de alimentos mássanos. Pocas investigaciones reflejan la ingesta de sal por parte de los consumidores; diversos estudios muestran que las personas tienen un deficiente reconocimiento de su ingesta de sal y no son plenamente conscientes de la relación “ingesta de s al-salud”. Las intervenciones preventivas más efectivas son las que involucran al consumidor desde su planificación, teniendo en cuenta los intereses, representaciones, preconceptos y posibilidades concretas de ejercer el autocuidado de las personas. Acciones sinérgicas entre el sector salud, la industriay las organizaciones de la sociedad civil para educar al consumidor y ofrecer entornos alimentarios más saludables redundarán en mayores y mejores resultados en la reducción de la ingesta de sal/sodio y su efecto perjudi-cial sobre la salud.

In Argentina and the world there is an effort to lower sal tintake, including consumer education and reduction of the salt content of processed foods. The Dietary Guidelines for Argentine Population published in 2000 specifically advise a maximum daily salt intake of 6 g.The World Health Organization Forum on Reducing Salt Intake in Populations recommends educating consumers and promoting environments that facilitate healthy food choices. There are not many investigations on the amount of salt consumers use, while several studies show that people have a poor recognition of their sal tintake and they are not fully aware of the relationship between salt intake and health. The most effective preventive interventions are those that involve consumer sat the very beginning of the planning process, taking into account their interests, representations, beliefs and their real possibilities of participating in their own care...

Na Argentina e no mundo existem ações tendentes areduzir a ingestão de sal; entre elas, intervenções deeducação ao consumidor e redução do conteúdo de salem a limentos processados. Os Guias Alimentícios para aPopulação Argentina editados em 2000 incluem umamensagem específica destinada a orientar uma ingestãoque não supere 6g diárias. O Foro da OrganizaçãoMundial da Saúde sobre a Redução do Consumo de Salna População recomenda educar o consumidor e promoverambientes que facilitem a escolha de alimentos maissaudáveis. Poucas pesquisas refletem a ingestão d e salpor parte dos consumidores; diversos estudos mostramque as pessoas têm um deficiente reconhecimento dasua iconscientes da relação “ingestão de sal – saúde”. Asintervenções preventivas mais efetivas são as queenvolvem o consumidor desde o seu planejamento,tendo em conta os intereses, representaconcebidos...

¿Está comprobado que la reducción de la ingesta de sal reduce la morbimortalidad por riesgo cardiovascular? / Is there evidence showing that salt intake reduction reduces cardiovascular morbidity and mortality risk?

Una revisión sistemática reciente de la colaboración Cochrane sobre el efecto de la reducción de sal en la dieta, concluyó que “aún no hay poder estadístico suficiente para excluir efectos clínicamente importantes de la dieta baja en sal en mortalidad o morbilidad cardiovascular en población normotensa o hipertensa”. Esta conclusión ha generado un debate importante porque la estimación que existe de que la reducción del consumo de sal prevendría los accidentes vasculares cerebrales en 24 por ciento y la enfermedad coronaria en 18 por ciento, ha llevado a las autoridades de salud de varios países a instaurar políticas públicas de reducción del consumo de sal. La revisión de estudios ecológicos y ensayos clínicos permite concluir que la reducción del consumo de sodio disminuye la presión arterial, y estudios metodológicamente sólidos de cohortes demuestran que el riesgo de eventos cardiovasculares disminuye progresivamente mientras más baja es la presión arterial. La combinación de estos dos resultados permite suponer que existiría un beneficio para las poblaciones al reducir la ingesta de sal aunque efectivamente no existan estudios que demuestren que en poblaciones con alto consumo de sal hay una reducción de eventos cardiovasculares al reducir la ingesta de sal.

A recent systematic review of Cochrane collaboration about the effect of reducing dietary salt concluded that “there is still insufficient power to exclude clinically important effects of reduced dietary salt on mortality or cardiovascular morbidity in normotensive or hypertensive populations”. This conclusion has generated an important debate, because the estimation that salt reduction can prevent 24 percent of strokes and 18 percent of myocardial infarctions has decided the health authorities of several nations to implement salt consumption reduction programs. The review of ecological studies and clinical trials allow to conclude that a reduction in salt consumption reduces blood pressure and methodological well conducted cohort studies has shown that cardiovascular events risk decreases progressively with lower levels of blood pressure. Combining this two finding we can assume that population should benefice from a decrease on salt consumption although there are no studies that shown a reduction in cardiovascular events in population with high sodium intake when dietary salt is reduced.

Análisis de la evidencia experimental que muestra efectos nocivos de la sal y su relación con la hipertensión arterial / Analysis of experimental evidence that shows adverse effects of salt and its relation to hypertension

El artículo publicado por Taylor y cols., en junio de 2010 en el American Journal of Hypertension, puso en duda la eficacia que tendría la reducción de la ingesta de sal en la dieta como medida para la prevención y tratamiento de la hipertensión arterial y de otras patologías de causa cardiovascular. La publicación de este artículo ha generado una gran controversia, y las respuestas no se hicieron esperar tanto desde sociedades médicas como científicas. Éstas han criticado fuertemente los resultados de este metaanálisis, señalando serias falencias metodológicas. En el presente artículo presentamos críticamente la evidencia experimental que muestra la importancia del aporte dietario de sal y su papel como determinante de la presión arterial. Describimos muy brevemente el paradigma que explica el papel de la ingesta de sal en la presión arterial (hipótesis y modelo de Guyton) y mencionamos evidencia experimental que lo sustenta. Comentamos brevemente los estudios clásicos que indican que la ingesta de sal (NaCl) contribuye directamente al desarrollo de hipertensión arterial y daño de tejidos diana. Finalmente, exponemos brevemente los datos experimentales que motivan la controversia en cuanto al papel de la sal (NaCl) o el sodio como agentes prohipertensivos.

The study by Taylor et al published in June 2010 in the American Journal of Hypertension questions the effectiveness of reducing salt intake in the diet in the prevention and treatment of high blood pressure and other cardiovascular conditions. The publication of this article has lead to great controversy and medical associations and learned societies responded promptly. The response criticized the results of the meta-analysis and pointed out its methodological shortcomings. In this review we critically appraise the experimental evidence that shows the importance of diet salt intake and its role as a determinant of blood pressure. We briefly describe the paradigm that explains the role of salt intake in contributing in the regulation of blood pressure (Guyton hypothesis and model) and we mention the experimental evidence that supports this. We briefly comment on the classical studies that indicate that salt intake (NaCl) contributes directly to the development of high blood pressure and target tissues. Finally, we briefly mention the experimental data that is related with the controversy on the role of salt (NaCl) or sodium as prohypertensive agents.

Papel de la sensibilidad a la sal y los polimorfismos genéticos como determinantes de la modificación de los factores de riesgo cardiovascular durante la pérdida de peso en sujetos con sobrepeso u obesidad / Role of salt sensitivity and genetic polymorphisms as determinants of the modification of cardiovascular risk factors during weight loss in overweight or obese subjects

El incremento de la ingesta de sal no siempre se acompaña de un aumento en la presión arterial; aquellos sujetos que así lo hacen, son denominados Sal Sensibles (SS), mientras que los que no, se denominan Sal Resistentes (SR). La sensibilidad a la sal se ha asociado con mayor riesgo cardiometabólico y es más frecuente en los sujetos obesos hipertensos, sin embargo, no todos los obesos son SS y se desconoce como se origina este fenotipo. Debido a que la obesidad es un estado proinflamatorio, se propone que es necesario cierto grado y/o tiempo de obesidad para ser SS. Es por ello, que en esta investigación se evaluó el cambio en el tiempo de las interleuquinas 6, 10 y 18 (IL-6, IL-10 e IL-18), adiponectina, leptina, glicemia, lípidos, insulina, depuración de creatinina, microalbuminuria, ADMA, metabolitos urinarios del óxido nrico (NO), y además se estudió la prevalencia de los polimorfismos genéticos más frecuentemente asociados a riesgo cardiometabólico de la IL-6, 10,18, y de la sintasa de NO endotelial (eNOS), en sujetos SR (n=11) y SS (n=17), con sobrepeso u obesidad grado I, que fueron sometidos por 18 semanas a dieta y ejercicio. Se encontró que la pérdida de peso revertió el estado SS, el cual fue mas evidente en los sujetos que tenían más tiempo de obesidad, mayor concentración de insulina y ADMA sanguíneo, menor excreción urinaria de los metabolito del NO, mayor índice IL-6/ circunferencia abdominal y presentaban al alelo ä"del polimorfismo 4ab de la eNOS, por lo que se concluye que la sensibilidad a la sal pudiera ser producto de la interacción entre los componentes inflamatorios, vasculares y metabólicos y probablemente sea modulada por el polimorfismo 4ab de la eNOS

Effect of nitric oxide inhibitor and donor substances on the infammatory process caused by endodontic irrigants

Nitric oxide (NO) has been considered a key molecule in infammation. OBJECTIVE: The aim of this study was to evaluate the effect of treatment with L-NAME and sodium nitroprussiate, substances that inhibit and release NO, respectively, on tissue tolerance to endodontic irrigants. MATERIAL AND METHODS: The vital dye exudation method was used in a rat subcutaneous tissue model. Injections of 2 percent Evans blue were administered intravenously into the dorsal penial vein of 14 male rats (200-300 g). The NO inhibitor and donor substances were injected into the subcutaneous tissue in the dorsal region, forming two groups of animals: G1 was inoculated with L-NAME and G2 with sodium nitroprussiate. Both groups received injections of the test endodontic irrigants: acetic acid, 15 percent citric acid, 17 percent EDTA-T and saline (control). After 30 min, analysis of the extravasated dye was performed by light absorption spectrophotometry (620 nm). RESULTS: There was statistically signifcant difference (p<0.05) between groups 1 and 2 for all irrigants. L-NAME produced a less intense infammatory reaction and nitroprussiate intensifed this process. CONCLUSIONS: Independently of the administration of NO inhibitors and donors, EDTA-T produced the highest irritating potential in vital tissue among the tested irrigating solutions.

Impact of Plasma-Lyte pH 7.4 on acid-base status and hemodynamics in a model of controlled hemorrhagic shock

OBJECTIVE: Intravenous infusion of crystalloid solutions is a cornerstone of the treatment of hemorrhagic shock. However, crystalloid solutions can have variable metabolic acid-base effects, perpetuating or even aggravating shock-induced metabolic acidosis. The aim of this study was to compare, in a controlled volume-driven porcine model of hemorrhagic shock, the effects of three different crystalloid solutions on the hemodynamics and acid-base balance. METHODS: Controlled hemorrhagic shock (40 percent of the total blood volume was removed) was induced in 18 animals, which were then treated with normal saline (0.9 percent NaCl), Lactated Ringer's Solution or Plasma-Lyte pH 7.4, in a blinded fashion (n = 6 for each group). Using a predefined protocol, the animals received three times the volume of blood removed. RESULTS: The three different crystalloid infusions were equally capable of reversing the hemorrhage-induced low cardiac output and anuria. The Lactated Ringer's Solution and Plasma-Lyte pH 7.4 infusions resulted in an increased standard base excess and a decreased serum chloride level, whereas treatment with normal saline resulted in a decreased standard base excess and an increased serum chloride level. The Plasma-Lyte pH 7.4 infusions did not change the level of the unmeasured anions. CONCLUSION: Although the three tested crystalloid solutions were equally able to attenuate the hemodynamic and tissue perfusion disturbances, only the normal saline induced hyperchloremia and metabolic acidosis.

Acute salt poisoning due to different oral rehydration solution (ORS) packet sizes.

The packing and composition of ORS has undergone a change since its introduction. In India, some companies are manufacturing smaller pouches (4.2 g) to be dissolved in 200 ml of water. Therefore, out of confusion some prescribers routinely advise the patients to dissolve the standard formulation ORS pouch (21 g) in a glass (200 ml) of water. Two cases are discussed. First patient developed salt poisoning due to improper dilution and recovered after rapid correction. In the second patient improper reconstitution led to hypernatremia and death.

Acidosis hiperclorémica: mito y realidad / Hyperchloremic acidosis

La acidosis metabólica es una alteración ácido-base frecuentemente observada en pacientes críticos. Aunque en situaciones extremas este desorden en sí mismo es amenazante para la vida, la presencia de una acidosis metabólica leve no siempre es nociva y puede ser un reflejo de la adaptación fisiológica del organismo a la injuria aguda. Diferentes autores han documentado el desarrollo de acidosis metabólica hiperclorémica asociada al aporte de grandes cantidades de solución salina 0,9 por ciento. Algunos consideran que se trata de una condición benigna y autolimitada, mientras otros sostienen que la acidosis hiperclorémica puede deteriorar la perfusión renal y esplácnica, sin embargo su relevancia clínica real es aún incierta. En un afán de evitar la aparición de acidosis hiperclorémica y sus potenciales efectos adversos, se han desarrollado cristaloides y coloides en formulaciones modificadas para que se asemejen más a la composición del plasma. En este artículo de revisión analizaremo slos mecanismos de producción de la acidosis metabólica hiperclorémica en base al abordaje físico-químico de Stewart; la evidencia existente sobre el impacto de este trastorno sobre las variables de desenlace de los pacientes críticos, y el rol clínico de las nuevas “soluciones balanceadas”.

Metabolic acidosis is an acid-base alteration frequently observed in critically ill patients. Even in extreme situations this disorder in itself is life threatening, the presence of a mild metabolic acidosis is not always harmful and may be the result of physiological adaptation of the organism to acute injury. Several authors have documented the development of hyperchloremic metabolic acidosis associated with the infusion of large amounts of 0.9 percent normal saline. Some consider this to be a benign and transient, while others argue that hyperchloremic acidosis can impair renal and splanchnic perfusion, but her real clinical relevance remains uncertain. In an effort to prevent the development of hyperchloremic acidosis and its potential adverse effects have been development formulations of crystalloid and colloid modified to more closely resemble the composition of the plasma. In this review article will discuss the mechanism of production of hyperchloremic metabolic acidosis by the physicochemical approach Stewart, the existing evidence on the impact of this disorder on the outcome variables in critically ill patients, and clinical role of new “balanced solutions”.

Relation between salt intake and blood pressure among Iranians

To determine the mean 24 hr urinary sodium [UNa] and chloride [UCl] excretion, and the association between these variables and blood pressure, since studies on the effect of habitual dietary salt intake and some electrolytes on blood pressure were reported different. Experimental population-based study Urban areas, Isfahan city, Iran Nine hundred and twelve randomly selected patients aged 20-60 years 24-hour urine and food records were collected three times in one month. Systolic [SBP] and diastolic [DBP] blood pressures, heart rate and sodium, potassium, calcium, chloride and creatinine levels in urine samples were measured. Estimated mean daily salt intake based on UNa excretion in Iranian population is 9.9 + 2.9 g/day [men: 11.1 + 3.0 g/day and women: 9.6 + 2.9 g/day; p = 0.001]. The UNa excretion value was 189.7 + 51.4 mmol for men and 164.6 + 49.8 mmol for women, with a significant difference [p = 0.001]. After adjustment for confounding factors and other urinary electrolytes, no relationship was found between UNa and SBP [b = 0.001, p = 0.89] or DBP [b = 0.007, p = 0.34] in the pooled data. Significant relationship was observed between UCl excretion and SBP in hypertensives [b = 0.113, p = 0.001], UNa excretion and DBP in the entire group [r = 0.04, p = 0.004] and in normotensive men [r = 0.036, p = 0.03]. Salt intake is one of the main factors affecting blood pressure among Iranian men but not women

Histopathologic evaluation of the peritoneum exposed to heat shock: experimental study in rats

PURPOSE: To evaluate histopathologic alterations of the peritoneum exposed to heat shock. METHODS: Sixty rats were randomly distributed into 6 groups: Heat Shock (HS), High Temperature (HT), Body Temperature (BT), Temperature 0oC (TZ), Sham (SH) and Control (CG) with 10 animals each. The peritoneal cavity of animals from groups HS, HT, BT and TZ was irrigated with NaCl solution 0.9 percent at temperatures 50°C, 0°C, 50°C, 37°C and 0°C, respectively. For animals from group SH, the procedures were simulated and those from group CG, laparotomy and biopsies were conducted. Twenty-four hours later, biopsies of the peritoneum for exams under light and electronic microscopy were performed. RESULTS: Edema was found in groups HS 80 percent, HT 60 percent, BT 30 percent TZ 70 percent, SH 40 percent and CG 30 percent. Vascular congestion was found in groups HS 20 percent, HT 30 percent, BT 10 percent and TZ 20 percent. Erythrocyte extravasation was found in groups HT 60 percent and SH 10 percent. Mesothelium destruction was found in 100 percent of specimens from groups HS, HT, BT, TZ, SH and CG 90 percent. Necrosis was found in groups HS 30 percent, HT 20 percent and BT 10 percent. The mean peritoneal thickness ranged from 42.26 μm (TZ) to 26.42 μm (CG). CONCLUSION: The heat shock caused no deaths, but promoted significant peritoneal edema without affecting the other histopathologic indicatives.

OBJETIVO: Avaliar alterações histopatológicas do peritônio exposto a choque térmico. MÉTODOS: Sessenta ratos foram distribuídos aleatoriamente em seis grupos: Choque Térmico (CT), Temperatura Elevada (TE), Temperatura 0°C (TZ) Sham (SH) e Controle (GC) com 10 animais. A cavidade peritoneal dos animais dos grupos CT, TE, TC e TZ foi irrigada com solução de NaCl 0,9 por cento nas temperaturas, 50°C e 0°C, 50°C, 37°C e 0°C, respectivamente. Nos animais do grupo SH foram simulados os procedimentos e nos do GC laparotomia e biópsias. Depois de 24 horas foram realizadas biópsias do peritônio para exames sob microscopia de luz e eletrônica. RESULTADOS: Edema foi encontrado nos grupos CT 80 por cento, TE 60 por cento, TC 30 por cento, TZ 70 por cento, SH 40 por cento e GC 30 por cento. Congestão vascular foi encontrada nos grupos CT 20 por cento, TE 30 por cento, TC 10 por cento e TZ 20 por cento. Extravasamento de hemácias foi encontrado nos grupos TE 60 por cento e SH 10 por cento. Destruição de mesotélio foi encontrada em 100 por cento dos espécimes dos grupos CT, TE, TC, TZ, SH e no grupo GC 90 por cento. Necrose foi encontrada nos grupos CT 30 por cento, TE 20 por cento e TC 10 por cento. A espessura média do peritônio variou de 42,26 μm (TZ) a 26,42 μm (GC). CONCLUSÃO: O choque térmico não causou óbitos, mas promoveu edema peritoneal significante sem alterar os demais indicadores histopatológicos.

Argentinean cultivars of Vitis vinifera grow better than european ones when cultured in vitro under salinity

Argentinean Vitis vinifera cultivars although originated from Europe, have clear ampeIographic and genotypic differences as compared with the European cultivars currently used in wine making. In vitro evaluation of salt tolerance has been used in many species. Our hypothesis was that Argentinean cultivars are more tolerant to salinity than European ones. Three European cultivars, Malbec, Cabernet Sauvignon and Chardonnay and four Argentinean cultivars, Cereza, Criolla Chica, Pedro Gimenez and Torrontes Riojano were tested by in vitro culture. Treatments included: 1) Control, 2) 60 mEq/L of a mixture of three parts of NaCl and one part of CaCl2 and 3) 90 mEq/L of the salt mixture. Results from two experiments (I and II) are reported. No differences were found in plant survival, expressed as % of the respective control, among cultivars. Leaf area, leaf, stem and total dry matter (DM) in Experiment I and leaf area, leaf number and leaf, stem, root and total DM in Experiment II, were higher in Argentinean cultivars than in European ones. We conclude that Argentinean cultivars show better performance in growing under salinity, especially in the highest salt concentration. Differences among cultivars, inside each group, were found for most of the measured variables.