Viviane I. C. Custódio

Nível sérico de zinco e sua associação com deficiência de vitamina A em crianças pré-escolares

OBJECTIVES: To identify the prevalence of zinc deficiency in a population with high prevalence of vitamin A deficiency; to verify whether zinc deficiency is associated with vitamin A deficiency in the population studied; to verify risk factors for zinc deficiency (sex, age, diarrhea and fever). METHOD: Cross-sectional study of 182 healthy children aged > 24 months and 48 and 48 and < 60 months tended to have lower zinc serum levels than children of other ages. Zinc serum levels were not changed by previous diarrhea and/or fever.

Vitamin A deficiency among Brazilian school-aged children in a healthy child service

Background/Objectives:Vitamin A deficiency (VAD) is a world public health problem contributing to the increase in childhood morbidity and mortality in developing countries and severe deficiency of vitamin A may lead to xerophthalmia and blindness. The objective of this study was to determine the prevalence of VAD among Brazilian school-aged children attended at a primary health unit and to verify if some considered risk factor was associated with VAD in this group.Subjects/Methods:A descriptive prospective transverse study was conducted on 103 randomly selected children. A total of 54 boys and 49 girls aged 5.5–11 years had the relative dose–response (RDR) test performed on. Possible ocular alterations related to vitamin A and the status of anemia, serum zinc, some acute-phase proteins, and anthropometric situation were determinate by an analytic design.Results:No child presented xerophthalmia. Serum retinol values lower than 1.05 and 0.7 μmol l−1, respectively were found in 26.2 and 5.8% of the children. The prevalence of hypovitaminosis detected by RDR test was 20.4%. The following variables and their relationship with VAD were evaluated: sex (P=0.33; 95% confidence interval 0.61–4.34), weight and height (P⩾0.5), hemoglobin (P=0.15), C-reactive protein (P=0.56; 95% confidence interval 0.75–18.26), α-1-acid-glycoprotein (P=0.56; 95% confidence interval 0.15–15.42) and serum zinc (P=0.31). None of these variables was related to VAD.Conclusions:In this population, the prevalence of VAD detected could be considered a public health problem. School-aged children can be considered at risk for VAD mainly of a subclinical level, even without some associated risk factors.

Zinc serum levels and their association with vitamin A deficiency in preschool children

OBJECTIVES To identify the prevalence of zinc deficiency in a population with high prevalence of vitamin A deficiency; to verify whether zinc deficiency is associated with vitamin A deficiency in the population studied; to verify risk factors for zinc deficiency (sex, age, diarrhea and fever). METHOD Cross-sectional study of 182 healthy children aged > or = 24 months and < 72 months. Peripheral blood samples were obtained from fasting children to determine zinc serum levels. Information about presence of diarrhea and/or fever during the 15 days preceding the study was also obtained. Vitamin A deficiency was identified by a serum 30-day dose-response test (+S30DR). RESULTS Of the children studied, 0.5% (1/182) presented zinc serum levels < 65 microg/dL; however, 74.7% (136/182) of them had vitamin A deficiency. Zinc serum levels were not correlated with retinol serum levels. Zinc serum levels were not changed by previous diarrhea and/or fever. There was no difference in zinc levels between boys and girls. Children aged between > or = 48 and < 60 months tended to have lower zinc serum levels than children of other ages. CONCLUSION Zinc deficiency prevalence was low and did not represent a risk factor for vitamin A deficiency. Children aged between > or = 48 and < 60 months tended to have lower zinc serum levels than children of other ages. Zinc serum levels were not changed by previous diarrhea and/or fever.

Impact of hypoxia on IGF-I, IGF-II, IGFBP-3, ALS and IGFBP-1 regulation and on IGF1R gene expression in children

UNLABELLED Hypoxia is one of many factors involved in the regulation of the IGF system. However, no information is available regarding the regulation of the IGF system by acute hypoxia in humans. OBJECTIVE The aim of this study was to evaluate the effect of acute hypoxia on the IGF system of children. DESIGN Twenty-seven previously health children (14 boys and 13 girls) aged 15 days to 9.5 years were studied in two different situations: during a hypoxemic state (HS) due to acute respiratory distress and after full recovery to a normoxemic state (NS). In these two situations oxygen saturation was assessed with a pulse-oximeter and blood samples were collected for serum IGF-I, IGF-II, IGFBP-1, IGFBP-3, ALS and insulin determination by ELISA; fluoroimmunometric assay determination for GH and also for IGF1R gene expression analysis in peripheral lymphocytes by quantitative real-time PCR. Data were paired and analyzed by the Wilcoxon non-parametric test. RESULTS Oxygen saturation was significantly lower during HS than in NS (P<0.0001). IGF-I and IGF-II levels were lower during HS than in NS (P<0.0001 and P=0.0004, respectively). IGFBP-3 levels were also lower in HS than in NS (P=0.0002) while ALS and basal GH levels were higher during HS (P=0.0015 and P=0.014, respectively). Moreover, IGFBP-1 levels were higher during HS than in NS (P=0.004). No difference was found regarding insulin levels. The expression of IGF1R mRNA as 2(-ΔΔCT) was higher during HS than in NS (P=0.03). CONCLUSION The above results confirm a role of hypoxia in the regulation of the IGF system also in humans. This effect could be direct on the liver and/or mediated by GH and it is not restricted to the hepatocytes but involves other cell lines. During acute hypoxia a combination of alterations usually associated with reduced IGF action was observed. The higher expression of IGF1R mRNA may reflect an up-regulation of the transcriptional process.

Sustained Ventricular Tachycardia and Cardiogenic Shock due to Scorpion Envenomation

We describe a case of severe scorpion envenomation in an adult patient, with the presence of very rapid sustained ventricular tachycardia followed by cardiogenic shock, which was reversed by scorpion antivenom administration. Scorpion venom causes cardiac changes that can lead to an environment favoring arrhythmogenesis.

1130 HEPATIC REGULATION OF THE INSULIN-LIKE GROWTH FACTOR (IGF) SYSTEM BY ACUTE HYPOXIA IN CHILDREN

Background and Aims: Adrenergic vascular hyper-responsiveness is a hallmark of different cardiometabolic disease, including essential hypertension, diabetes, obesity, metabolic syndrome, heart failure and chronic kidney disease. Previous studies have shown that sympathetic activation and insulin resistance are closely related each other, but the cause-and-effect relationship remains undefined. Iron overload impairs glucose metabolism in hemochromatosis patients by either insulin resistance or decreased insulin secretion. There are no data on the effect of iron overload on the adrenergic overdrive. Methods: The study groups consisted of 15 iron-loaded hemochromatosis male patients without iron-related organ damage, at diagnosis, and 10 age-matched healthy male controls. We measured, during a 30-minute resting period, beat-to-beat blood pressure (Finapres), heart rate (ECG) and postganglionic muscle sympathetic nerve traffic (MSNA) via microneurography into the peroneal nerve. Seven hemochromatosis patients were evaluated also after iron depletion. All patients underwent Magnetic Resonance for the assessment of hepatic iron concentration (HIC). Metabolic syndrome (defined according to the ATPIII criteria), essential hypertension, diabetes, obesity, heart and kidney failure, and cirrhosis were considered metabolic confounders and they represented the exclusion criteria. Insulin resistance was estimated by HOMA index (normal value <2.77). Results: In hemochromatosis patients at diagnosis, mean serum ferritin was 825±407mg/L, HIC 206±57mmol/g and HOMA index 1.7±0.82. MSNA values were significantly higher than in controls (63.53±10.93 vs 35.36±10.85 bursts/100 heart beats, p = 0.0001). In iron depleted patients sympathetic activation significantly decreased (68.24±12.26 vs 40.39±11.04 bursts/100 heart beats, p = 0.0156) reaching the normal range. Conclusions: The present study indicates that iron overloaded male patients with hemochromatosis are characterized by a hyperadrenergic state. Iron overload contributes to adrenergic hyper-responsiveness and could be directly involved in the overactivity of the autonomic nervous system also in the absence of an insulin resistance condition. Iron-dependent generation of reactive oxygen species might be involved in the pathogenesis of the adrenergic overdrive and more generally in cardiovascular damage.

P-85 Is there a role for vitamin A on the regulation of IGF-I in children?

IGF system and vitamin A (VA) are important regulators of human growth and a wide range of physiological processes. Growth hormone and nutritional status are the main regulators of IGF system; however the role of the micronutrients is still not clear. The objective was to verify the effect of VA supplementation on IGF-I levels in VA deficient children. Ninety-four healthy children aged 5.5–11 years with regular follow-up in a pediatric clinic and no clinic evidence of vitamin A deficiency (VAD) entered the study. In order to access VA status serum retinol were determined by HPLC at baseline (BR) and 30 days (R30) after VA supplementation (200 000 IU of trans-retinyl palmitate) by +S30DR test (serum 30-day dose-response test). +S30DR was considered positive when (R30 −BR)× 100/R30 was 20%. IGF-I was also measured in both samples, by IRMA. Children were further divided in VAD and non-VAD. They were considered VAD if BR 1.05mmol/L or +S30DR positive. The samples were paired and compared using a nonparametric paired test. According to BR and +S30DR 24.5% and 28.7% of the children were considered VAD, respectively. IGF-I levels increased significantly with VA supplementation in the VAD group, either considering BR levels criterion (P = 0.001) or +S30DR test criterion (P = 0.004) while no difference was observed between baseline IGF-I and day-30 IGF-I in the non-VAD group. Baseline IGF-I was lower in the VAD than in the non-VAD group either considering BR (median: 190 vs. 260 mg/L) or +S30DR (median: 190 vs. 260mg/L) as criterion to VAD. No difference was found regarding day-30 IGF-I levels between VAD and non-VAD children. Conclusion: IGF-I levels increase after VA supplementation in children with subclinical VAD, these results suggest a possible role for VA on IGF-I regulation and support the idea that some of VA actions can be mediated by IGF-I, including the VA-supported growth.