Marcadores de estrés oxidativo y su relación con el estado nutricional en adultos, Ecuador / Relationships between biomarkers of oxidative stress and nutritional status in adults, Ecuador

Se evaluó la relación entre biomarcadores de estrés oxidativo (ácido úrico, bilirrubina y proteína C-reactiva) con el estado nutricional en 321 adultos de Ecuador, pertenecientes al personal administrativo de la Universidad Técnica del Norte, con edades de 43 ± 10 años, (46,30% femenino y 53,61% masculino). Se obtuvo información sociodemográfica, de estilo de vida y epidemiológica; se calculó el índice de Masa Corporal (IMC), porcentaje de grasa y agua corporal, se midió la circunferencia de la cintura (CC) y la presión arterial y se determinó las concentraciones de ácido úrico, bilirrubina y Proteína C reactiva (PCR). Se encontró que 17,9% de la población presentó obesidad y 51,72% sobrepeso. Los valores más elevados de ácido úrico se encontraron en obesos, hipertensos y en quienes realizan actividad física. La bilirrubina total, directa e indirecta se encontró en límites superiores en los grupos con obesidad abdominal, y con actividad física. Las variables % de grasa y de agua influyen en la PCR en el grupo con baja grasa corporal y en las mujeres. En hombres, la PCR se asocia con IMC y CC. En los grupos sobrepeso, alta grasa corporal y PHT, el ácido úrico mostró relación con el % de grasa y la CC En los obesos con el % de agua e IMC y en los grupos obesidad abdominal e HT se asoció con % de agua y CC Se concluye que el porcentaje de agua corporal es un importante indicador nutricional para el desarrollo de estrés oxidativo en esta población.

In this work it was evaluated the relationship between oxidative stress biomarkers (uric acid, bilirubin and C-reactive protein) with nutritional status in 321 adults of Ecuador, belonging to administrative staff of of the Universidad Tècnica del Norte , aged 43 ± 10 years old (46 30% female and 53.61% male). Socio demographic and epidemiological information and lifestyle were obtained through a survey; The Body Mass Index (BMI) and body fat and body water percentages were calculated; waist circumference (WC) and blood pressure was measured. Determinations of uric acid, bilirubin, and serum C-reactive protein (PCR) were performed. 17.9% of the populations were obese and 51.72% overweight. The highest values of uric acid were found in obese, hypertensive and physical activity groups. The total direct and indirect bilirubin were found in upper limits in abdominal obesity and physical activity groups. The CRP level was influenced by % fat and % water in the low body fat group and in females. In male, BMI and WC were associated with CRP. Uric acid showed relationship with % fat and WC in overweight, high body fat and PHT groups, uric acid was associated with the % water and BMI in obese. Finally, uric acid was associated with % water and the WC in the abdominal obesity, and HT groups’ .The body water percentage is an important indicator to development of oxidative stress in this population.

Análise vetorial de impedância bioelétrica (BIVA) em recém-nascidos pré-termo estáveis / Bioelectrical impedance vector analysis (BIVA) in stable preterm newborns

OBJETIVO: Observar o comportamento dos vetores ponteados no gráfico de resistência e de reactância corrigidos pelo comprimento corporal (RXc) através da análise vetorial de impedância bioelétrica (BIVA) e os valores de ângulo de fase (AF) em recém-nascidos (RNs) pré-termo estáveis, considerando a hipótese que o RN pré-termo apresenta o seu comportamento vetorial na BIVA sugestivo de menor quantidade de água e de tecidos moles corporais, comparativamente à referência do RN a termo. MÉTODOS: Foi realizado estudo de corte transversal em RNs pré-termo, de ambos os sexos, que se encontravam em uma unidade de cuidados intermediários de um hospital terciário. Coletaram-se dados relacionados ao nascimento e à alimentação, bem como dados de bioimpedância elétrica (800 mA, 50 kHz). Os gráficos e as análises vetoriais foram realizados através do BIVA software. RESULTADOS: Um total de 108 RNs pré-termo foram estudados, separados por faixa etária (< 7 dias e > 7 dias). A maioria dos RNs pré-termo encontrou-se fora da normalidade (acima dos intervalos de tolerância de 95%) existentes na literatura para RNs a termo, e observou-se uma tendência para a dispersão dos pontos no quadrante superior direito no gráfico RXc. O AF dos RNs < 7 dias foi de 4,92° (±2,18), e a dos RNs > 7 dias, de 4,34° (±2,37). CONCLUSÃO: Os RNs pré-termo se comportam de maneira semelhante entre si. A maioria deles possui menor quantidade absoluta de água corporal e apresenta menor quantidade tanto de massa livre de gordura quanto de massa gorda, em valores absolutos, quando comparados com os RNs a termo.

OBJECTIVE: To observe the behavior of the plotted vectors on the RXc (R - resistance - and Xc - reactance corrected for body height/length) graph through bioelectrical impedance analysis (BIVA) and phase angle (PA) values in stable premature infants, considering the hypothesis that preterm infants present vector behavior on BIVA suggestive of less total body water and soft tissues, compared to reference data for term infants. METHODS: Cross-sectional study, including preterm neonates of both genders, in-patients admitted to an intermediate care unit at a tertiary care hospital. Data on delivery, diet and bioelectrical impedance (800 mA, 50 kHz) were collected. The graphs and vector analysis were performed with the BIVA software. RESULTS: A total of 108 preterm infants were studied, separated according to age (< 7 days and > 7 days). Most of the premature babies were without the normal range (above the 95% tolerance intervals) existing in literature for term newborn infants and there was a tendency to dispersion of the points in the upper right quadrant, RXc plan. The PA was 4.92° (±2.18) for newborns < 7 days and 4.34° (±2.37) for newborns > 7 days. CONCLUSION: Premature infants behave similarly in terms of BIVA and most of them have less absolute body water, presenting less fat free mass and fat mass in absolute values, compared to term newborn infants.

Uso de la bioimpedancia eléctrica para la estimación de la composición corporal en niños y adolescentes / Use of bioelectrical impedance for the prediction of body composition in children and adolescents

El análisis de la composición corporal constituye el eje central de la valoración del estado nutricional. Su estimación en el área pediátrica ha cobrado gran relevancia debido a la creciente prevalencia de la obesidad en las primeras etapas de la vida y los efectos adversos sobre la salud. La bioimpedancia eléctrica es uno de los métodos desarrollados para estimar la composición corporal; tanto en investigación como en el área clínica. Se fundamenta en la oposición de las células, tejidos o líquidos corporales al paso de una corriente eléctrica. Este método mide el agua corporal total y permite estimar la masa corporal libre de grasa y la masa grasa. Entre sus ventajas están el bajo costo, facilidad de transporte, inocuidad, sencillez en el manejo y la baja variabilidad interobservador. Este artículo hace una revisión de la bioimpedancia eléctrica como técnica para evaluar la composición corporal. Se presentan los aspectos relacionados a las suposiciones metodológicas, así como sus ventajas, limitaciones y aplicaciones de la bioimpedancia eléctrica en la estimación de la composición corporal en niños y adolescentes. Se concluye que la validez y aplicabilidad demostrada por la bioimpedancia eléctrica en estudios epidemiológicos, le permite ubicarse dentro de los métodos recomendables para el estudio de la composición corporal en niños y adolescentes.

The analysis of body composition constitutes the center of nutritional state evaluation. Its estimation in the pediatric area has become highly relevant due to the growing prevalence of obesity in the first stages of life and the adverse effects on health. Bioelectrical impedance is one of the methods developed to estimate body composition in research as well as in clinic. Bioelectrical impedance is based on the opposition of cells, tissues or body fluids to the pass of an electric current. This method measures total body water and allows the estimation of fat and fat free body mass. Among its advantages are low cost, easy transportation and handling and low variability between observers. This article makes a revision of bioelectric impedance as a technique to evaluate body composition. Aspects related to its methodological assumptions are presented, as well as its advantages, limitations and applications in the estimation of body composition of children and adolescents. The applicability and validity shown by bioelectric impedance in epidemiologic studies place it next to reliable methods for the study of body composition.

Validación de ecuaciones antropométricas para evaluar composición corporal en niños preescolares chilenos / Validation of equations to assess body composition using anthropometric data in Chilean preschool children

Background: Validated equations to measure body composition in Chilean preschool children are lacking, since the only international equation available was developed in obese, and undernourished Caucasian children. Due to the increase in overweight and obesity in Chile, it is essential to have simple and reliable instruments to assess children. Aim: To design and validate anthropometric equations to estimate body fat (BF) and total body water (TBW) to be applicable in children aged 3 to 5 years, using deuterated water dilution as a reference method. Materials and Methods: Weight, height, circumferences and skinfold thickness were evaluated in 238 children aged 3 to 5 years, attending Junta Nacional de Jardines Infantiles (JUNJI). Several equations were developed using multiple regression models to estimate body water and fat. The proposed equations were validated against a sample of 77 children previously evaluated, using Bland and Alunan agreement analysis, that compares average differences of both methods with the average of predicted and estimated values. Results: New equations for TBW and BF were obtained, accounting for 86 percent and 72 percent in estimated variability. The agreement analysis showed a mean difference 0.001 ± 0.32 and 0.07 ± 0.56 kg, for TBW and BF, respectively, confirming the validity of the equations. Conclusions: The new validated equations in Chilean children aged 3 to 5 years, have an adequate and predictive capacity, especially useful for evaluating TBW and BF change in cohorts.

Body composition by a three compartment model in adult Indian male and female subjects.

The body composition of 10 adult Indian male and female subjects was investigated by a three compartment model, using measurements of Total Body Water (TBW) by deuterium dilution, and of body density by hydrodensitometry. The three compartment model yielded significantly different (P < 0.005) estimates of percent body fat of 15.9+/-3.8 and 19.7+/-4.2% and of the Fat Free Mass (FFM) of 41+/-3.3 kg and 33.9+/-4.1 kg in the male and female subjects respectively. The hydration of the FFM was 0.704+/-0.032 in the males and 0.719+/-0.024 in the females; this difference was not signifcant between groups. The density of the FFM, measured from estimates of percent body fat by the 3 compartment approach and of body density by hydrodensitometry, was 1.107+/-0.014 in the males and 1.101+/-0.001 in the females with no significant differences between the groups. This study demonstrates differences in body composition between BMI matched healthy adult male and female subjects. Although there are significant differences for % Fat and FFM between the sexes, there are no significant differences in the hydration fraction and the density of the FFM.

Secretory effect of serotonin on jejunal response to cholera toxin, in dog

A substância mediadora liberada pela toxina da cólera e que estimula a secreçäo intestinal é ainda desconhecida. Sabe-se que a serotonina está envolvida no estímulo secretor intestinal de água e eletrólitos. Tendo em vista a avaliaçäo de um provável papel da serotonina na induçäo secretora jejunal pela toxina da cólera, calcularam-se os volumes de água, sódio, potássio e cloreto, bem como os níveis imunorreativos de serotonina, em alça de Thiry-Vella canina. A administraçäo de toxina provocou um aumento na secreçäo de todos os eletrólitos e do fluxo de serotonina. Esses resultados sugerem que a toxina da cólera induz à liberaçäo de serotonina na luz intestinal, talvez como um mediador da secreçäo hidroeletrolítica entérica