Browsing by Author "Villagran, Andrea"

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    Concordance between Lactose Quick Test, hydrogen-methane breath test and genotyping for the diagnosis of lactose malabsorption in children
    (2018) Rojo, C.; Jaime, F.; Azocar, L.; Hernandez, C.; Villagran, Andrea; Miquel P., Juan Francisco; Arancibia Hernández, Gloria Cecilia
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    Differences in lung glutathione metabolism may account for rodent susceptibility in elastase-induced emphysema development
    (AMER PHYSIOLOGICAL SOC, 2009) Borzone, Gisella R.; Liberona, Leonel F.; Bustamante, Andrea P.; Saez, Claudia G.; Olmos, Pablo R.; Vecchiola, Andrea; Villagran, Andrea; Serrano, Carolina; Reyes, Tatiana P.
    Borzone GR, Liberona LF, Bustamante AP, Saez CG, Olmos PR, Vecchiola A, Villagran A, Serrano C, Reyes TP. Differences in lung glutathione metabolism may account for rodent susceptibility in elastase-induced emphysema development. Am J Physiol Regul Integr Comp Physiol 296: R1113-R1123, 2009. First published January 14, 2009; doi: 10.1152/ajpregu.90361.2008.-Syrian Golden hamsters develop more severe emphysema than Sprague-Dawley rats after intratracheal instillation of the same dose of elastase/body weight. Although species variations in antielastase defenses may largely explain these results, other variables, such as differences in lung antioxidants, cannot be overlooked since oxidative stress modulates antiprotease activity. We propose that elastase instillation might affect lung glutathione (GSH) metabolism differently in these species. Our aim was to study in hamsters and rats, lung glutathione metabolism at different times, from the stage of diffuse alveolar damage to advanced emphysema. We measured total and oxidized glutathione content as well as activity and expression of enzymes related to GSH synthesis and redox cycling: gamma-glutamylcysteine synthetase, glutathione peroxidase, and glutathione reductase. Whereas rats showed no significant changes in these measurements, hamsters showed significant derangement in GSH metabolism early after elastase instillation: 25% fall in total GSH (P < 0.05) with no increase in oxidized glutathione associated with reduced enzyme activities 24 h after elastase [60% for gamma-glutamylcysteine synthetase (P < 0.01), 30% for glutathione peroxidase (P < 0.01), and 75% for glutathione reductase (P < 0.001)]. GSH homeostasis was restored at the end of the first week, involving transient increased expression of these enzymes. We conclude that elastase induces significant alterations in GSH metabolism of hamster lungs and no overall change in rat lungs. Although differences in disease severity may account for our findings, the hamster becomes vulnerable to functional inhibition of alpha(1)-antitrypsin by oxidants and thus, even more susceptible to injury than it would be, considering only its low alpha(1)-antitrypsin level.
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    Helicobacter pylori vacA virulence factor in uncultured Helicobacter heilmannii sensu lato from an infected child
    (2016) Hernandez, Caroll; Serrano Honeyman, Carolina; Villagran, Andrea; Torres Montes, Paula Javiera; Venegas, Alejandro; Harris D., Paul R.; Hernandez, Caroll; Serrano Honeyman, Carolina; Villagran, Andrea; Torres Montes, Paula Javiera; Venegas, Alejandro; Harris D., Paul R.
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    Iron Deficiency and IL1 beta Polymorphisms in Helicobacter pylori-infected Children
    (2016) Serrano Honeyman, Carolina; Villagran, Andrea; Toledo, H.; Crabtree, J.; Harris D., Paul R.; Serrano Honeyman, Carolina; Villagran, A.; Toledo, H.; Crabtree, J.; Harris D., Paul R.
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    Iron Status and Helicobacter pylori Infection in Symptomatic Children: An International Multi-Centered Study
    (2013) Magalhaes Queiroz, Dulciene Maria; Harris, Paul; Sanderson, Ian R.; Windle, Henry J.; Walker, Marjorie M.; Camargos Rocha, Andreia Maria; Rocha, Gifone Aguiar; Carvalho, Simone Diniz; Souto Bittencourt, Paulo Fernando; Fonseca de Castro, Lucia Porto; Villagran, Andrea; Serrano, Carolina; Kelleher, Dermot; Crabtree, Jean E.
    Objective: Iron deficiency (ID) and iron deficiency anaemia (IDA) are global major public health problems, particularly in developing countries. Whilst an association between H. pylori infection and ID/IDA has been proposed in the literature, currently there is no consensus. We studied the effects of H. pylori infection on ID/IDA in a cohort of children undergoing upper gastrointestinal endoscopy for upper abdominal pain in two developing and one developed country. Methods: In total 311 children (mean age 10.7±3.2 years) from Latin America - Belo Horizonte/Brazil (n = 125), Santiago/Chile (n = 105) - and London/UK (n = 81), were studied. Gastric and duodenal biopsies were obtained for evaluation of histology and H. pylori status and blood samples for parameters of ID/IDA. Results: The prevalence of H. pylori infection was 27.7% being significantly higher (p<0.001) in Latin America (35%) than in UK (7%). Multiple linear regression models revealed H. pylori infection as a significant predictor of low ferritin and haemoglobin concentrations in children from Latin-America. A negative correlation was observed between MCV (r = −0.26; p = 0.01) and MCH (r = −0.27; p = 0.01) values and the degree of antral chronic inflammation, and between MCH and the degree of corpus chronic (r = −0.29, p = 0.008) and active (r = −0.27, p = 0.002) inflammation. Conclusions: This study demonstrates that H. pylori infection in children influences the serum ferritin and haemoglobin concentrations, markers of early depletion of iron stores and anaemia respectively.