Browsing by Author "Valenzuela, A"

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    Chronic renal failure in pediatrics 1996 - Chilean survey
    (SPRINGER VERLAG, 1999) Lagomarsimo, E; Valenzuela, A; Cavagnaro, F; Solar, E
    The Nephrology Branch of the Chilean Pediatric Society has greatly influenced the development of government health plans regarding the management and care of patients under 18 years with chronic renal failure (CRF). In order to assess the status of children with CRF in Chile up to 1996, a questionnaire was sent to all pediatric nephrologists in charge of those children. The total sample was of 227 patients under 18 years, giving a national prevalence of 42.5 and an incidence of 5.7 per million inhabitants; of these patients, 50.7% were male, 58.6% over 10 years and 15% younger than 5 years. The most frequent etiologies of CRF were: obstructive uropathy, 18.1%; hypo/dysplasia, 16.7%; reflux nephropathy, 16.7%; and glomerulopathies, 16.3%. Although 48% of patients were on conservative medical treatment, 42.2% of these were in end-stage renal disease, 22.9% were on dialysis, and 29.1% had undergone renal transplantation. Of the dialysis group, 75% were on peritoneal dialysis. Of the transplanted children, 78.8% had normal renal function, but 16.7% returned to dialysis. Three-year graft survival and patient survival were 68% and 94%, respectively.
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    Comparative effect of fish oil feeding and other dietary fatty acids on plasma lipoproteins, biliary lipids, and hepatic expression of proteins involved in reverse cholesterol transport in the rat
    (KARGER, 2005) Morgado, N; Rigotti, A; Valenzuela, A
    Background: While elevated plasma high-density lipoprotein (HDL) levels has been associated to a reduction in cardiovascular risk, dietary fish oils rich in omega-3 polyunsaturated fatty acids (PUFAs) may protect against this disease. The protective effect of HDL is associated to its participation in the reverse cholesterol transport pathway. On the other hand, omega-3 PUFAs decrease plasma HDL levels compared to other fatty acids, which may suggest an effect on reverse cholesterol transport. Aim: In this work, the effect of dietary fish oil on the fatty acid composition of hepatic membranes, plasma lipoprotein cholesterol profile, biliary lipids, and the expression of proteins involved in reverse cholesterol transport, was compared to other dietary oils having a different degree of fatty acid unsaturation. Methods: Male rats were fed a semi synthetic diet containing fish oil ( omega -3), sunflower oil (omega-6), olive oil (omega-9) or coconut oil (saturated). Hepatic membrane fatty acid composition, plasma cholesterol levels, lipoprotein cholesterol profile, biliary lipids, hepatic mRNA levels for lecithin cholesterol acyltransferase, hepatic lipase, apo E, and apo A-I, and hepatic protein levels of the scavenger receptor class B type I, caveolin-1, and the ATP binding cassette transporter A1 were analyzed. Plasma apo A-I and apo E protein levels were also evaluated. Results: Compared to the other diets, omega - 3 PUFAs significantly changed omega-3/omega-6 fatty acid ratio of hepatic membranes, caused a reduction of plasma total and HDL cholesterol, and selectively increased biliary cholesterol secretion. No modifi cation in the expression levels of lecithin cholesterol acyltransferase, hepatic lipase, apo A-I and apo E mRNA was observed. Hepatic scavenger receptor class B type I, caveolin-1, and the ATP binding cassette transporter A1 protein levels were also not affected. Plasma apo A-I, but not apo E, was reduced. Conclusions: These results show that dietary omega-3 PUFAs reduce plasma HDL cholesterol and increase biliary cholesterol without concomitant modifi cations in the expression of key genes and proteins involved in reverse cholesterol transport. These fi ndings suggest that functional changes in the activity of these proteins as consequence of the incorporation of omega3 PUFAs into hepatic membranes and plasma lipoproteins may underlie the effect of fi sh oil feeding on plasma and hepatic cholesterol metabolism in the rat. Copyright (c) 2005 S. Karger AG, Basel.
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    Dispersal and extrapolation on the accuracy of temporal predictions from distribution models for the Darwin's frog
    (2017) Uribe, D; Soto, C; Valenzuela, A; Bizama, G; Simonetti Zambello, Javier; Pliscoff, Patricio
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    Supplementation of female rats with alpha-linolenic acid or docosahexaenoic acid leads to the same omega-6/omega-3 LC-PUFA accretion in mother tissues and in fetal and newborn brains
    (KARGER, 2004) Valenzuela, A; von Bernhardi, R; Valenzuela, V; Ramirez, G; Alarcon, R; Sanhueza, J; Nieto, S
    Background: Maternal omega-3 fatty acid supplementation has been suggested to provide docosahexaenoic acid (DHA) for the normal brain development during gestation. DHA can be given as such ( preformed) or through the omega-3 precursor alpha-linolenic acid (LNA) which is transformed into DHA by elongation and desaturation reactions. Western diet provides low amounts of LNA and DHA; therefore, supplementation with these omega-3 fatty acids has been suggested for pregnant women. However, the bioequivalence of LNA ingestion to DHA supplementation has not been established. Methods: Recently weaning female Wistar rats were fed a diet containing a small amount of LNA and no DHA. The animals were daily supplemented 40 days before mating, during pregnancy, and until delivery with 60 mg/kg of LNA or 6 mg/kg of DHA dissolved in coconut oil. Fatty acids were given as ethyl ester derivatives. Controls received coconut oil. The fatty acid composition of blood plasma, erythrocytes, liver, visceral adipose tissue, and brain segments (frontal cortex, hippocampus, and cerebellum) was analyzed. Brain segments obtained from 16- and 19-day-old fetuses and from 2- and 21-day- old rats were also analyzed for fatty acid composition. Results: Supplementation with LNA and DHA induced a similar accretion of DHA in plasma, erythrocytes, liver, and brain segments of the mothers. The adipose tissue showed a higher DHA accretion after DHA-supplementation. The DHA accretion in frontal cortex, hippocampus, and cerebellum obtained from the fetuses and the newborn rats was similar when the mothers were supplemented with LNA and DHA. Our results show that under our experimental conditions a similar accretion of DHA in the different tissues of the mothers and in the brain segments of fetuses and newborn rats is obtained after LNA and DHA supplementation. Conclusion: LNA and DHA, at the amounts given in this study, show a similar bioequivalence for DHA accretion in different tissues of the mother and in brain segments of fetuses and newborn rats. Copyright (C) 2004 S. Karger AG, Basel.