Browsing by Author "Allende, Fidel"
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- Item3-Epi-25 Serum 25-Hydroxyvitamin D3 Concentrations in Chilean Children Between 5 and 8 Years(KARGER, 2018) Arancibia, Monica; Seiltgens, Cristian; Poggi, Helena; Allende, Fidel; Solari, Sandra; Peredo, Soledad; Trincado, Claudia; Garcia, Hernan; Moore, Rosario; Dapremont, Ivonne; Andrade, Daniela; Sifaqui, Sofia; Ossa, Jt; Campino, Carmen; Carvajal, Cristian; Fardella, Carlos; Baudrand, Rene; Sanchez, Ximena; Martinez Aguayo, Alejandro
- ItemBacterial identification based on protein mass spectrometry: A new insight at the microbiology of the 21st century(SOC CHILENA INFECTOLOGIA, 2012) Garcia, Patricia; Allende, Fidel; Legarraga, Paulette; Huilcaman, Marcos; Solari, SandraBacterial identification is important for the proper treatment of infected patients hospitalized with serious infections especially in critical care units. Identification by conventional methods used in microbiology laboratories takes at least 16 hours since a culture is positive. The introduction of mass spectrometry, specifically MALDI-TOF MS (matrix-assisted laser desorption/ionization time-of-flight mass spectrometer) in the microbiology laboratory could mean a radical change in the identification accuracy, turn around time (6 minutes per bacteria) and cost (about 5 times cheaper than conventional identification). Since its introduction in clinical microbiology laboratories in 2008, many reports about its usefulness in identifying microorganisms from colonies, as well as directly from positive blood cultures and urine samples have been published. This review describes MALDI-TOF MS methodology, its identification performance for bacteria (aerobic and anaerobic), mycobacterium and yeasts, its future applications in microbiology and its main disadvantages.
- ItemBile acids synthesis decreases after laparoscopic sleeve gastrectomy(2016) Escalona, Alex; Muñoz, R.; Irribarra Pastenes, Verónica; Solari Gajardo, Sandra; Allende, Fidel; Miquel P., Juan Francisco
- ItemCitosine-Adenine-Repeat Microsatellite of 11 beta-hydroxysteroid dehydrogenase 2 Gene in Hypertensive Children(OXFORD UNIV PRESS, 2016) Valdivia, Carolina; Carvajal, Cristian A.; Campino, Carmen; Allende, Fidel; Martinez Aguayo, Alejandro; Baudrand, Rene; Vecchiola, Andrea; Lagos, Carlos F.; Tapia Castillo, Alejandra; Fuentes, Cristobal A.; Aglony, Marlene; Solari, Sandra; Kalergis, Alexis M.; Garcia, Hernan; Owen, Gareth I.; Fardella, Carlos E.BACKGROUND
- ItemClinical, Biochemical, and Genetic Characteristics of "Nonclassic" Apparent Mineralocorticoid Excess Syndrome(2019) Tapia Castillo, Alejandra; Baudrand Biggs, René; Vaidya, Anand; Campino Johnson, María del Carmen; Allende, Fidel; Carvajal Maldonado, Cristián Andrés; Vecchiola Cárdenas, Andrea Paola; Lagos Arévalo, Carlos Fernando; Fuentes Zúñiga, Cristóbal Andrés; Fardella B., Carlos; Solari, Sandra; Martínez Aguayo, Alejandro Gregorio; García Bruce, Hernán; Valdivia, Carolina; Tapia Castillo, Alejandra; Baudrand Biggs, René; Vaidya, Anand; Campino Johnson, María del Carmen; Allende, Fidel; Carvajal Maldonado, Cristián Andrés; Vecchiola Cárdenas, Andrea Paola; Lagos Arévalo, Carlos Fernando; Fuentes Zúñiga, Cristóbal Andrés; Fardella B., Carlos; Solari, Sandra; Martínez Aguayo, Alejandro Gregorio; García Bruce, Hernán; Valdivia, Carolina
- ItemCortisol/cortisone ratio and matrix metalloproteinase-9 activity are associated with pediatric primary hypertension(2016) Martínez Aguayo, Alejandro Gregorio; Campino Johnson, María del Carmen; Baudrand Biggs, René; Carvajal, C.; García Bruce, Hernán; Aglony Imbarack, Marlene Elizabeth; Bancalar, R.; García, L.; Loureiro Pérez, Carolina Andrea; Vecchiola Cárdenas, Andrea Paola; Tapia Castillo, A.; Valdivia, C.; Sanhueza, S.; Fuentes, C.; Lagos, C.; Solari, S.; Allende, Fidel; Kalergis Parra, Alexis Mikes; Fardella B., Carlos; Martínez Aguayo, Alejandro Gregorio; Campino Johnson, María del Carmen; Baudrand Biggs, René; Carvajal, C.; García Bruce, Hernán; Aglony Imbarack, Marlene Elizabeth; Bancalar, R.; García, L.; Loureiro Pérez, Carolina Andrea; Vecchiola Cárdenas, Andrea Paola; Tapia Castillo, A.; Valdivia, C.; Sanhueza, S.; Fuentes, C.; Lagos, C.; Solari, S.; Allende, Fidel; Kalergis Parra, Alexis Mikes; Fardella B., Carlos
- ItemDepressive symptoms are associated with higher morning plasma cortisol in primary care subjects(2018) Capponi, Valentina; Carrasco, Carmen; Macchiavello, Stefano; Undurraga, Juan; Campino Johnson, María del Carmen; Carvajal, Cristian; Gomez, Teresita; Weiss, Cristian; Aedo Campos, Igor Iván; Vecchiola Cárdenas, Andrea Paola; Allende, Fidel; Solari, Sandra; Fardella B., Carlos; Baudrand Biggs, René; Capponi, Valentina; Carrasco, Carmen; Macchiavello, Stefano; Undurraga, Juan; Campino Johnson, María del Carmen; Carvajal, Cristian; Gomez, Teresita; Weiss, Cristian; Aedo Campos, Igor Iván; Vecchiola, Andrea; Allende, Fidel; Solari, Sandra; Fardella B., Carlos; Baudrand Biggs, René
- ItemDexmedetomidine metabolic clearance is not affected by fat mass in obese patients(2018) Rolle, A.; Paredes, S.; Cortínez Fernández, Luis Ignacio; Anderson, B. J.; Quezada Sanhueza, Nicolás; Solari, S.; Allende, Fidel; Torres, J.; Cabrera, D.; Contreras, V.; Carmona, J.; Ramirez, C.; Oliveros, A. M.; Ibacache Figueroa, Mauricio Enrique
- ItemDexmedetomidine pharmacokinetics in the obese(2015) Cortínez Fernández, Luis Ignacio; Anderson, Brian J.; Holford, Nick H. G.; Puga, Valentina; De La Fuente, Natalia; Auad, Hernán; Solari Gajardo, Sandra; Allende, Fidel; Ibacache Figueroa, Mauricio Enrique
- ItemDifferent effects of progesterone and estradiol on chimeric and wild type aldosterone synthase in vitro(2013) Vecchiola Cárdenas, Andrea Paola; Lagos Arévalo, Carlos Fernando; Fuentes Zúñiga, Cristóbal Andrés; Allende, Fidel; Campino Johnson, María del Carmen; Valdivia, Carolina.; Tapia Castillo, Alejandra.; Owen, Gareth Ivor; Solari Gajardo, Sandra; Carvajal Maldonado, Cristián Andrés; Fardella B., Carlos; Ogishima, Tadashi.; Mukai, Kuniaki.Abstract Background Familial hyperaldosteronism type I (FH-I) is caused by the unequal recombination between the 11beta-hydroxylase (CYP11B1) and aldosterone synthase (CYP11B2) genes, resulting in the generation of a CYP11B1/B2 chimeric gene and abnormal adrenal aldosterone production. Affected patients usually show severe hypertension and an elevated frequency of stroke at a young age. Aldosterone levels rise during pregnancy, yet in pregnant women with FH-1, their hypertensive condition either remains unchanged or may even improve. The purpose of this study was to investigate in vitro whether female sex steroids modulate the activity of chimeric (ASCE) or wild type (ASWT) aldosterone synthase enzymes. Methods We designed an in vitro assay using HEK-293 cell line transiently transfected with vectors containing the full ASCE or ASWT cDNAs. Progesterone or estradiol effects on AS enzyme activities were evaluated in transfected cells incubated with deoxycorticosterone (DOC) alone or DOC plus increasing doses of these steroids. Results In our in vitro model, both enzymes showed similar apparent kinetic parameters (Km = 1.191 microM and Vmax = 27.08 microM/24 h for ASCE and Km = 1.163 microM and Vmax = 36.98 microM/24 h for ASWT; p = ns, Mann–Whitney test). Progesterone inhibited aldosterone production by ASCE- and ASWT-transfected cells, while estradiol demonstrated no effect. Progesterone acted as a competitive inhibitor for both enzymes. Molecular modelling studies and binding affinity estimations indicate that progesterone might bind to the substrate site in both ASCE and ASWT, supporting the idea that this steroid could regulate these enzymatic activities and contribute to the decay of aldosterone synthase activity in chimeric gene-positive patients. Conclusions Our results show an inhibitory action of progesterone in the aldosterone synthesis by chimeric or wild type aldosterone synthase enzymes. This is a novel regulatory mechanism of progesterone action, which could be involved in protecting pregnant women with FH-1 against hypertension. In vitro, both enzymes showed comparable kinetic parameters, but ASWT was more strongly inhibited than ASCE. This study implicates a new role for progesterone in the regulation of aldosterone levels that could contribute, along with other factors, to the maintenance of an adequate aldosterone-progesterone balance in pregnancy.Abstract Background Familial hyperaldosteronism type I (FH-I) is caused by the unequal recombination between the 11beta-hydroxylase (CYP11B1) and aldosterone synthase (CYP11B2) genes, resulting in the generation of a CYP11B1/B2 chimeric gene and abnormal adrenal aldosterone production. Affected patients usually show severe hypertension and an elevated frequency of stroke at a young age. Aldosterone levels rise during pregnancy, yet in pregnant women with FH-1, their hypertensive condition either remains unchanged or may even improve. The purpose of this study was to investigate in vitro whether female sex steroids modulate the activity of chimeric (ASCE) or wild type (ASWT) aldosterone synthase enzymes. Methods We designed an in vitro assay using HEK-293 cell line transiently transfected with vectors containing the full ASCE or ASWT cDNAs. Progesterone or estradiol effects on AS enzyme activities were evaluated in transfected cells incubated with deoxycorticosterone (DOC) alone or DOC plus increasing doses of these steroids. Results In our in vitro model, both enzymes showed similar apparent kinetic parameters (Km = 1.191 microM and Vmax = 27.08 microM/24 h for ASCE and Km = 1.163 microM and Vmax = 36.98 microM/24 h for ASWT; p = ns, Mann–Whitney test). Progesterone inhibited aldosterone production by ASCE- and ASWT-transfected cells, while estradiol demonstrated no effect. Progesterone acted as a competitive inhibitor for both enzymes. Molecular modelling studies and binding affinity estimations indicate that progesterone might bind to the substrate site in both ASCE and ASWT, supporting the idea that this steroid could regulate these enzymatic activities and contribute to the decay of aldosterone synthase activity in chimeric gene-positive patients. Conclusions Our results show an inhibitory action of progesterone in the aldosterone synthesis by chimeric or wild type aldosterone synthase enzymes. This is a novel regulatory mechanism of progesterone action, which could be involved in protecting pregnant women with FH-1 against hypertension. In vitro, both enzymes showed comparable kinetic parameters, but ASWT was more strongly inhibited than ASCE. This study implicates a new role for progesterone in the regulation of aldosterone levels that could contribute, along with other factors, to the maintenance of an adequate aldosterone-progesterone balance in pregnancy.
- ItemDownregulation of exosomal miR-192-5p and miR-204-5p in subjects with nonclassic apparent mineralocorticoid excess.(2019) Tapia Castillo, Alejandra.; Barros, Eric.; Allende, Fidel; Vecchiola Cárdenas, Andrea Paola; Fardella B., Carlos; Carvajal Maldonado, Cristián Andrés; Guanzon, Dominic.; Palma, Carlos.; Lai, Andrew.; Salomón Gallo, Carlos Francisco.Abstract Background The “nonclassic” apparent mineralocorticoid excess (NC-AME) has been identified in approximately 7% of general population. This phenotype is characterized by low plasma renin activity (PRA), high serum cortisol (F) to cortisone (E) ratio, low cortisone, high Fractional Excretion of potassium (FEK) and normal-elevated systolic blood pressure (SBP). An early detection and/or identification of novel biomarkers of this phenotype could avoid the progression or future complications leading to arterial hypertension. Isolation of extracellular vesicles, such as exosomes, in specific biofluids support the identification of tissue-specific RNA and miRNA, which may be useful as novel biomarkers. Our aim was to identify miRNAs within urinary exosomes associated to the NC-AME phenotype. Methods We perform a cross-sectional study in a primary care cohort of 127 Chilean subjects. We measured BP, serum cortisol, cortisone, aldosterone, PRA. According to the previous reported, a subgroup of subjects was classified as NC-AME (n = 10). Urinary exosomes were isolated and miRNA cargo was sequenced by Illumina-NextSeq-500. Results We found that NC-AME subjects had lower cortisone (p < 0.0001), higher F/E ratio (p < 0.0001), lower serum potassium (p = 0.009) and higher FEK 24 h (p = 0.03) than controls. We found miR-204-5p (fold-change = 0.115; p 0.001) and miR-192-5p (fold-change = 0.246; p 0.03) are both significantly downregulated in NC-AME. miR-192-5p expression was correlated with PRA (r = 0.45; p 0.028) and miR-204-5p expression with SBP (r = − 0.48, p 0.027) and F/E ratio (r = − 0.48; p 0.026). Conclusions These findings could support a potential role of these miRNAs as regulators and novel biomarkers of the NC-AME phenotype.
- ItemHigher Dehydroepiandrosterone Levels in Prepubertal Children Born Very Preterm(KARGER, 2018) Mericq, Veronica; Martinez Aguayo, Alejandro; Iniguez, German; Poggi, Helena; D'Apremont, Ivonne; Moore, Rosario; Arancibia, Monica; Garcia, Hernan; Peredo, Soledad; Trincado, Claudia; Sifaqui, Sofia; Tomas Ossa, Jose; Fardella, Carlos; Carvajal, Cristian; Campino, Carmen; Baudrand, Rene; Solari, Sandra; Allende, Fidel
- ItemHypertensive Patients That Respond to Aldosterone Antagonists May Have a Nonclassical 11β-HSD2 Deficiency.(2017) Tapia Castillo, Alejandra; Carvajal Maldonado, Cristián Andrés; Allende, Fidel; Campino Johnson, María del Carmen; Fardella B., Carlos
- ItemIdentification of novel 11β-HSD1 inhibitors by combined ligand- and structure-based virtual screening(2014) Lagos Arévalo, Carlos Fernando; Vecchiola Cárdenas, Andrea Paola; Allende, Fidel; Fuentes Zúñiga, Cristóbal Andrés; Tichauer, Juan E.; Valdivia, Carolina; Solari Gajardo, Sandra; Campino Johnson, María del Carmen; Tapia-Castillo, Alejandra; Baudrand Biggs, René; Villarroel, Pia; Cifuentes, Mariana; Owen, Gareth Ivor; Carvajal, Cristian A.; Fardella B., Carlos
- ItemInsulin Resistance Parameters in Children Who Were Born Very Preterm and Adequate for Gestational Age(KARGER, 2018) Garcia, Hernan; Poggi, Helena; Arancibia, Monica; Peredo, Soledad; Trincado, Claudia; Moore, Rosario; D'Apremont, Ivonne; Andrade, Daniela; Sifaqui, Sofia; Ossa, J. T.; Campino, Carmen; Carvajal, Cristian; Fardella, Carlos; Baudrand, Rene; Solari, Sandra; Allende, Fidel; Martinez Aguayo, Alejandro
- ItemLC-MS/MS Method for the Simultaneous Determination of Free Urinary Steroids(2014) Allende, Fidel; Solari Gajardo, Sandra; Campino Johnson, María del Carmen; Carvajal Maldonado, Cristián Andrés; Lagos Arévalo, Carlos Fernando; Vecchiola Cárdenas, Andrea Paola; Baudrand Biggs, René; Owen, Gareth Ivor; Fardella B., Carlos
- ItemPolymorphisms in the RAC1 Gene Are Associated With Hypertension Risk Factors in a Chilean Pediatric Population(OXFORD UNIV PRESS, 2014) Tapia Castillo, Alejandra; Carvajal, Cristian A.; Campino, Carmen; Vecchiola, Andrea; Allende, Fidel; Solari, Sandra; Garcia, Lorena; Lavanderos, Sergio; Valdivia, Carolina; Fuentes, Cristobal; Lagos, Carlos F.; Martinez Aguayo, Alejandro; Baudrand, Rene; Aglony, Marlene; Garcia, Hernan; Fardella, Carlos E.The GTPase Rac1 has been implicated in hypertension as a modulator of mineralocorticoid receptor activity. Our aim is to investigate the frequency of polymorphisms rs10951982 (intron 1, G > A) and rs836478 (intron 3, T > C) in the RAC1 gene and perform association studies with clinical and biochemical parameters in a Chilean pediatric cohort.
- ItemProgressive 11β-hydroxysteroid dehydrogenase type 2 insufficiency as kidney function declines(2024) Uslar N., Thomas; Newman, Andrew J.; Tapia Castillo, Alejandra; Carvajal Maldonado, Cristián Andrés; Fardella B., Carlos; Allende, Fidel; Solari, Sandra; Tsai, Laura C.; Milks, Julia; Cherney, Michael; Stouffer, David G.; Auchus, Richard; Brown, Jenifer M.; Baudrand Biggs, René; Vaidya, AnandBackground It has been postulated that chronic kidney disease (CKD) is a state of relative 11 beta-hydroxysteroid dehydrogenase type 2 (11 beta HSD2) insufficiency, resulting in increased cortisol-mediated mineralocorticoid receptor (MR) activation. We hypothesized that relative 11 beta HSD2 insufficiency manifests across a wide spectrum of progressively declining kidney function, including within the normal range. Methods Adult participants were recruited at 2 academic centers. A discovery cohort (n = 500) enrolled individuals with estimated glomerular filtration rate (eGFR) ranging from normal to CKD stage 5, in whom serum cortisol-to-cortisone (F/E) was measured as a biomarker of 11 beta HSD2 activity. A validation cohort (n = 101) enrolled only individuals with normal kidney function (eGFR >= 60 mL/min/1.73 m(2)) in whom 11 beta HSD2 activity was assessed via serum F/E and 11-hydroxy-to-11-keto androgen (11OH/K) ratios following multiple maneuvers: oral sodium suppression test, dexamethasone suppression test (DST), and ACTH-stimulation test (ACTHstim). Results In the discovery cohort, lower eGFR was associated with higher F/E (P-trend < .001). Similarly, in the validation cohort, with normal eGFR, an inverse association between eGFR and both F/E and 11OH/K ratios was observed (P-trend < .01), which persisted following DST (P-trend < .001) and ACTHstim (P-trend < .05). The fractional excretion of potassium, a marker of renal MR activity, was higher with higher F/E (P-trend < .01) and with lower eGFR (P-trend < .0001). Conclusion A continuum of declining 11 beta HSD2 activity was observed with progressively lower eGFR in individuals spanning a wide spectrum of kidney function, including those with apparently normal kidney function. These findings implicate cortisol-mediated MR activation in the pathophysiology of hypertension and cardiovascular disease in CKD.
- ItemRocuronium pharmacokinetics and pharmacodynamics in the adductor pollicis and masseter muscles(2016) Vega, E. A.; Ibacache Figueroa, Mauricio Enrique; Anderson, B. J.; Holford, N. H. G.; Nazar Jara, C.; Solari Gajardo, Sandra; Allende, Fidel; Cortínez Fernández, Luis Ignacio
- ItemSeasonal 25-hydroxy Vitamin D3 variations in school-aged children from Santiago de Chile(KARGER, 2019) Poggi, Helena; Dominguez, Gonzalo; Monica, Arancibia; Moore, Rosario; D'Apremont, Ivonne; Solari, Sandra; Allende, Fidel; Sifaqui, Sofia; Garcia, Hernan; Martinez Aguayo, Alejandro