117 results on '"Cristian A. Carvajal"'
Search Results
2. Novel metabolomic profile of subjects with non-classic apparent mineralocorticoid excess
- Author
-
Alejandra Tapia-Castillo, Cristian A. Carvajal, Xaviera López-Cortés, Andrea Vecchiola, and Carlos E. Fardella
- Subjects
Medicine ,Science - Abstract
Abstract Nonclassic apparent mineralocorticoid excess (NC-AME) is proposed as a novel clinical condition with a mild phenotypic spectrum that ranges from normotension to severe hypertension. This condition is mainly characterized by a high serum cortisol to cortisone ratio (F/E) and concomitant low cortisone (E), however further metabolic changes in NC-AME have not been studied. A cross-sectional study was performed in a primary-care cohort of 396 Chilean subjects, which were classified in two groups: NC-AME (n = 28) and healthy controls (n = 27). A discovery study based in untargeted metabolomics assay in serum samples from both groups was performed by UPLC-Q-TOF/MS. Global metabolomic variations were assayed by principal component analysis and further compared by orthogonal partial least-squares discriminant analysis (OPLS-DA). NC-AME subjects exhibited higher values of blood pressure, fractional excretion of potassium, and lower plasma renin activity and urinary sodium to potassium ratio. Metabolomic analyses showed 36 differentially regulated metabolites between NC-AME and control subjects. A ROC curve analyses identified eight metabolites with high discriminatory capacity between NC-AME and control subjects. Moreover, gamma-l-glutamyl-l-methionine sulfoxide and 5-sulfoxymethylfurfural, exhibited significant association with cortisone, which are potential biomarkers of NC-AME, however further assays should elucidate its biological role in setup and progression of this phenotype.
- Published
- 2021
- Full Text
- View/download PDF
3. Downregulation of exosomal miR-192-5p and miR-204-5p in subjects with nonclassic apparent mineralocorticoid excess
- Author
-
Alejandra Tapia-Castillo, Dominic Guanzon, Carlos Palma, Andrew Lai, Eric Barros, Fidel Allende, Andrea Vecchiola, Carlos E. Fardella, Carlos Salomón, and Cristian A. Carvajal
- Subjects
Nonclassic AME ,Mineralocorticoid receptor ,MicroRNA ,Exosomes ,Hypertension ,Medicine - Abstract
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
- Published
- 2019
- Full Text
- View/download PDF
4. Serum Alpha-1-Acid Glycoprotein-1 and Urinary Extracellular Vesicle miR-21-5p as Potential Biomarkers of Primary Aldosteronism
- Author
-
Cristian A. Carvajal, Alejandra Tapia-Castillo, Jorge A. Pérez, and Carlos E. Fardella
- Subjects
primary aldosteronism (PA) ,biomarker ,lipocalin ,miR-21-5p ,extracellular vesicles ,AGP1 ,Immunologic diseases. Allergy ,RC581-607 - Abstract
Primary aldosteronism (PA) is the most common cause of secondary hypertension and reaches a prevalence of 6-10%. PA is an endocrine disorder, currently identified as a broad-spectrum phenotype, spanning from normotension to hypertension. In this regard, several studies have made advances in the identification of mediators and novel biomarkers of PA as specific proteins, miRNAs, and lately, extracellular vesicles (EVs) and their cargo.AimTo evaluate lipocalins LCN2 and AGP1, and specific urinary EV miR-21-5p and Let-7i-5p as novel biomarkers for PA.Subjects and MethodsA cross-sectional study was performed in 41 adult subjects classified as normotensive controls (CTL), essential hypertensives (EH), and primary aldosteronism (PA) subjects, who were similar in gender, age, and BMI. Systolic (SBP) and diastolic (DBP) blood pressure, aldosterone, plasma renin activity (PRA), and aldosterone to renin ratio (ARR) were determined. Inflammatory parameters were defined as hs-C-reactive protein (hs-CRP), PAI-1, MMP9, IL6, LCN2, LCN2-MMP9, and AGP1. We isolated urinary EVs (uEVs) and measured two miRNA cargo miR-21-5p and Let-7i-5p by Taqman-qPCR. Statistical analyses as group comparisons were performed by Kruskall-Wallis, and discriminatory analyses by ROC curves were performed with SPSS v21 and Graphpad-Prism v9.ResultsPA and EH subjects have significantly higher SBP and DBP (p
- Published
- 2021
- Full Text
- View/download PDF
5. Urinary Exosomes and Their Cargo: Potential Biomarkers for Mineralocorticoid Arterial Hypertension?
- Author
-
Eric R. Barros and Cristian A. Carvajal
- Subjects
arterial hypertension ,exosomes ,biomarker ,water-electrolyte balance ,microRNA ,urine ,Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
Arterial hypertension (AHT) currently affects approximately 40% of adults worldwide, and its pathological mechanisms are mainly related to renal, vascular, and endocrine systems. Steroid hormones as aldosterone and cortisol are highly relevant to human endocrine physiology, and also to endocrine hypertension. Pathophysiological conditions, such as primary aldosteronism, affect approximately 10% of patients diagnosed with AHT and are secondary to a high production of aldosterone, increasing the risk also for cardiovascular damage and heart diseases. Excess of aldosterone or cortisol increases the activity of the mineralocorticoid receptor (MR) in epithelial and non-epithelial cells. Current research in this field highlights the potential regulatory mechanisms of the MR pathway, including pre-receptor regulation of the MR (action of 11BHSD2), MR activating proteins, and the downstream genes/proteins sensitive to MR (e.g., epithelial sodium channel, NCC, NKCC2). Mineralocorticoid AHT is present in 15–20% of hypertensive subjects, but the mechanisms associated to this condition have been poorly described, due mainly to the absence of reliable biomarkers. In this way, steroids, peptides, and lately urinary exosomes are thought to be potential reporters of biological processes. This review highlight exosomes and their cargo as potential biomarkers of metabolic changes associated to mineralocorticoid AHT. Recent reports have shown the presence of RNA, microRNAs, and proteins in urinary exosomes, which could be used as biomarkers in physiological and pathophysiological conditions. However, more studies are needed in order to benefit from exosomes and the exosomal cargo as a diagnostic tool in mineralocorticoid AHT.
- Published
- 2017
- Full Text
- View/download PDF
6. Hipertensión arterial mineralocorticoidea
- Author
-
Carlos E. Fardella B., Dr., Cristian A. Carvajal, Dr., Carmen Campino, Dra., Alejandra Tapia, Dra., Hernán García, Dr., and Alejandro Martínez-Aguayo, Dr.
- Subjects
Hipertensión arterial mineralocorticoidea ,hipera-aldosteronismo primario ,aldosterona ,hipertensión secundaria ,Medicine - Abstract
La hipertensión arterial (HTA) dependiente de mineralocorticoides representa actualmente una de las formas secundarias de hipertensión más prevalentes. Entre las causas más conocidas está el hiperaldosteronismo primario (HAP). A nivel renal, la aldosterona reabsorbe sodio y agua aumentando el volumen intravascular y la presión arterial. Actualmente la prevalencia de HAP, detectada por la razón aldosterona/actividad renina plasmática (ARR) que es considerado el mejor test de screening, es cercana al 10% en población hipertensa. Por otra parte, defectos congénitos o adquiridos en la enzima 11β-Hidroxiesteroide deshidrogenasa tipo 2 (11β-HSD2) resultan en una ineficiente inactivación de cortisol a cortisona favoreciendo la aparición de hipertensión por activación del receptor mineralocorticoideo. La actividad de esta enzima se evalúa midiendo la razón cortisol/cortisona en suero o en orina de 24 horas. Recientemente, hemos observado déficit parciales de la actividad de la enzima 11β-HSD-2 en alrededor del 15% de los pacientes hipertensos esenciales los que podrían ser tratados con bloqueadores específicos del receptor mineralocorticoide y/o con corticoides de acción prolongada sin actividad mineralocorticoide como dexametasona o betametasona.
- Published
- 2013
- Full Text
- View/download PDF
7. Hiperaldosteronismo primario y otras formas de hipertension arterial endocrina
- Author
-
Cristian A. Carvajal, Rene F. Baudrand, and Carlos E. Fardella
- Subjects
Hipertensión arterial mineralocorticoidea ,hiperaldosteronismo primario ,11β-HSD2 ,aldosterona ,cortisol ,hipertensión secundaria ,Medicine - Abstract
La hipertensión arterial (HTA) dependiente de mineralocorticoides representa actualmente una de las formas secundarias de hipertensión de mayor prevalencia. Entre las causas más prevalentes está el hiperaldosteronismo primario (HAP) cuya prevalencia es cercana al 10% de la población de hipertensos. El HAP se detecta principalmente por una elevación de la razón aldosterona a actividad renina plasmática (ARR), ya que la hipokalemia es infrecuente de encontrar. La fisiopatología del HAP se presenta como un desequilibrio en el control electrolítico a nivel renal, por mayor actividad del receptor mineralocorticoides (MR), lo cual aumenta el volumen intravascular y la presión arterial. Recientemente se ha demostrado también que el exceso de aldosterona afecta también el endotelio vascular, el tejido cardiaco entre otros. Este exceso puede ser por una alteración a nivel de la glándula suprarrenal (generalmente hiperplasia o adenoma) o formas genéticas (familiares). Por otra parte, alteraciones parciales o totales de la enzima 11β-Hidroxiesteroide deshidrogenasa tipo 2 (11β-HSD2) resulta en una metabolización total o parcial de cortisol, imitando los efectos de aldosterona sobre MR. La actividad de esta enzima se evalúa midiendo la razón cortisol a cortisona en suero por HPLC-MS/MS. La prevalencia de alteraciones parciales de la actividad de la enzima 11β-HSD2 en estudios de cohorte alcanza en alrededor del 15% en población hipertensa. El diagnóstico del HAP o deficiencias de 11BHSD2, permitiría un tratamiento específico del cuadro hipertensivo mediantes el uso de bloqueadores del receptor mineralocorticoideo y/o uso de corticoides de acción prolongada sin actividad mineralocorticoidea como dexametasona o betametasona.
- Published
- 2016
- Full Text
- View/download PDF
8. Clinical, biochemical, and miRNA profile of subjects with positive screening of primary aldosteronism and nonclassic apparent mineralocorticoid excess
- Author
-
Alejandra Tapia-Castillo, Cristian A. Carvajal, Jorge A. Pérez, and Carlos E. Fardella
- Subjects
Endocrinology ,Endocrinology, Diabetes and Metabolism - Published
- 2022
9. Aldosterone and renin concentrations were abnormally elevated in a cohort of normotensive pregnant women
- Author
-
Alejandra Tapia-Castillo, Carlos E. Fardella, Valentina Pasten, Cristian A. Carvajal, and Andrea Leiva
- Subjects
medicine.medical_specialty ,Pregnancy ,Aldosterone ,business.industry ,Endocrinology, Diabetes and Metabolism ,medicine.disease ,Plasma renin activity ,chemistry.chemical_compound ,Endocrinology ,Primary aldosteronism ,Blood pressure ,chemistry ,Internal medicine ,Diabetes mellitus ,Renin–angiotensin system ,Medicine ,business ,Subclinical infection - Abstract
Background During pregnancy, the renin-angiotensin-aldosterone system (RAAS) undergoes major changes to preserve normal blood pressure (BP) and placental blood flow and to ensure a good pregnancy outcome. Abnormal aldosterone-renin metabolism is a risk factor for arterial hypertension and cardiovascular risk, but its association with pathological conditions in pregnancy remains unknown. Moreover, potential biomarkers associated with these pathological conditions should be identified. Aim To study a cohort of normotensive pregnant women according to their serum aldosterone and plasma renin levels and assay their small extracellular vesicles (sEVs) and a specific protein cargo (LCN2, AT1R). Methods A cohort of 54 normotensive pregnant women at term gestation was included. We determined the BP, serum aldosterone, and plasma renin concentrations. In a subgroup, we isolated their plasma sEVs and semiquantitated two EV proteins (AT1R and LCN2). Results We set a normal range of aldosterone and renin based on the interquartile range. We identified 5/54 (9%) pregnant women with elevated aldosterone and low renin levels and 5/54 (9%) other pregnant women with low aldosterone and elevated renin levels. No differences were found in sEV-LCN2 or sEV-AT1R. Conclusion We found that 18% of normotensive pregnant women had either high aldosterone or high renin levels, suggesting a subclinical status similar to primary aldosteronism or hyperreninemia, respectively. Both could evolve to pathological conditions by affecting the maternal vascular and renal physiology and further the BP. sEVs and their specific cargo should be further studied to clarify their role as potential biomarkers of RAAS alterations in pregnant women.
- Published
- 2021
10. Testosterona inhibe la actividad de la aldosterona sintasa silvestre y quimérica in vitro
- Author
-
Andrea Vecchiola, Cristóbal A. Fuentes, Cristian A. Carvajal, Carmen Campino, Fidel Allende, Alejandra Tapia-Castillo, Carlos F. Lagos, and Carlos E. Fardella
- Subjects
General Medicine - Published
- 2021
11. Clinical and molecular characterization of Chilean patients with X-linked hypophosphatemia
- Author
-
C. García, Danisa Ivanovic-Zuvic, Michael T. Collins, E. Gallardo, Carolina Loureiro, O. Contreras, Macarena Jiménez, P. Schneider, Pablo Florenzano, Gabriel Cavada, Cristian A. Carvajal, and Gilberto González
- Subjects
0301 basic medicine ,medicine.medical_specialty ,Pediatrics ,medicine.diagnostic_test ,business.industry ,Endocrinology, Diabetes and Metabolism ,030209 endocrinology & metabolism ,medicine.disease ,X-linked hypophosphatemia ,Rheumatology ,Elevated alkaline phosphatase ,Natural history ,03 medical and health sciences ,0302 clinical medicine ,Quality of life ,Internal medicine ,Orthopedic surgery ,medicine ,030101 anatomy & morphology ,medicine.symptom ,business ,Hypophosphatemia ,Genetic testing - Abstract
We report the most comprehensive clinical and molecular characterization of XLH patients performed in Chile. We show high prevalence of musculoskeletal burden and pain, associated with significantly impaired physical capacity and quality of life, with many relevant complications presenting more frequently than previously reported in cohorts from developed countries. Our current understanding of the clinical presentation and natural history of X-linked hypophosphatemia (XLH) comes mainly from cohorts from developed countries, with limited data on the clinical and genetic abnormalities of XLH patients in South America. To describe the clinical, biochemical, and molecular presentation of patients with XLH in Chile. Patients with XLH referred by endocrinologist throughout Chile were included. Demographic data and clinical presentation were obtained from a clinical interview. Surveys were applied for quality of life (QoL), pain, and functionality. FGF23 was measured by ELISA, and genetic testing was performed. Imaging studies were conducted to assess skeletal and renal involvement. We included 26 patients, aged 2–64 years, from 17 unrelated Chilean families. All pediatric patients but only 40% of adults were receiving conventional therapy, while 65% of all patients had elevated alkaline phosphatase. All patients had mutations in PHEX, including 5 novel variants. Radiographic skeletal events (RSE) and enthesopathies in adults were frequent (34% and 85%, respectively). The duration of treatment was associated with fewer RSE (p < 0.05). Most adults reported pain and impaired QoL, and 50% had impaired physical capacity. The number of enthesopathies was associated with worse pain and stiffness scores (p < 0.05). Chilean patients with XLH have a high prevalence of musculoskeletal burden associated with pain and impaired physical capacity and QoL, especially in adults who were generally undertreated. These data identify a significant unmet need, inform our understanding of the current status of patients, and can guide care for XLH patients in similarly socioeconomically defined countries.
- Published
- 2021
12. Extending the endocrine hypertension spectrum: novel nonclassic apparent mineralocorticoid excess
- Author
-
Alejandra Tapia-Castillo, Cristian A. Carvajal, and Carlos E. Fardella
- Subjects
medicine.medical_specialty ,Endocrinology ,business.industry ,Endocrinology, Diabetes and Metabolism ,Diabetes mellitus ,Internal medicine ,APPARENT MINERALOCORTICOID EXCESS ,medicine ,medicine.disease ,business ,Endocrine hypertension - Published
- 2021
13. Apparent Mineralocorticoid Excess
- Author
-
Cristian A. Carvajal, Alejandra Tapia-Castillo, Thomas Uslar, and Carlos E. Fardella
- Published
- 2022
14. Classic and Nonclassic Apparent Mineralocorticoid Excess Syndrome
- Author
-
Rene Baudrand, Andrea Vecchiola, Cristian A. Carvajal, Alejandra Tapia-Castillo, and Carlos E. Fardella
- Subjects
0301 basic medicine ,medicine.medical_specialty ,Hydrocortisone ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,Population ,Context (language use) ,030204 cardiovascular system & hematology ,Essential hypertension ,Biochemistry ,Plasma renin activity ,03 medical and health sciences ,0302 clinical medicine ,Endocrinology ,Mineralocorticoid receptor ,Mineralocorticoids ,Internal medicine ,Renin–angiotensin system ,Humans ,Medicine ,education ,education.field_of_study ,business.industry ,Mineralocorticoid Excess Syndrome, Apparent ,Biochemistry (medical) ,Prognosis ,medicine.disease ,Cortisone ,Phenotype ,030104 developmental biology ,Blood pressure ,Apparent mineralocorticoid excess syndrome ,business - Abstract
Context Arterial hypertension (AHT) is one of the most frequent pathologies in the general population. Subtypes of essential hypertension characterized by low renin levels allowed the identification of 2 different clinical entities: aldosterone-mediated mineralocorticoid receptor (MR) activation and cortisol-mediated MR activation. Evidence Acquisition This review is based upon a search of Pubmed and Google Scholar databases, up to August 2019, for all publications relating to endocrine hypertension, apparent mineralocorticoid excess (AME) and cortisol (F) to cortisone (E) metabolism. Evidence Synthesis The spectrum of cortisol-mediated MR activation includes the classic AME syndrome to milder (nonclassic) forms of AME, the latter with a much higher prevalence (7.1%) than classic AME but different phenotype and genotype. Nonclassic AME (NC-AME) is mainly related to partial 11βHSD2 deficiency associated with genetic variations and epigenetic modifications (first hit) and potential additive actions of endogenous or exogenous inhibitors (ie, glycyrrhetinic acid-like factors [GALFS]) and other factors (ie, age, high sodium intake) (second hit). Subjects with NC-AME are characterized by a high F/E ratio, low E levels, normal to elevated blood pressure, low plasma renin and increased urinary potassium excretion. NC-AME condition should benefit from low-sodium and potassium diet recommendations and monotherapy with MR antagonists. Conclusion NC-AME has a higher prevalence and a milder phenotypical spectrum than AME. NC-AME etiology is associated to a first hit (gene and epigene level) and an additive second hit. NC-AME subjects are candidates to be treated with MR antagonists aimed to improve blood pressure, end-organ damage, and modulate the renin levels.
- Published
- 2019
15. Primary Aldosteronism, Aldosterone, and Extracellular Vesicles
- Author
-
Cristian A Carvajal, Alejandra Tapia-Castillo, Jorge A Pérez, and Carlos E Fardella
- Subjects
Extracellular Vesicles ,MicroRNAs ,Endocrinology ,Gene Expression Regulation ,Hyperaldosteronism ,Hypertension ,Renin ,Humans ,Prognosis ,Aldosterone ,Biomarkers - Abstract
Primary aldosteronism (PA) is an endocrine related condition leading to arterial hypertension due to inappropriately high and unregulated aldosterone concentration. Recently, a broad spectrum of PA has been recognized, which brings new challenges associated with early identification of this condition that affect renal epithelial and extrarenal tissues. Reports have shown the potential role of extracellular vesicles (EVs) and EV cargo as novel and complementary biomarkers in diagnosis and prognosis of PA. In vivo and in vitro studies have identified specific EV surface antigens, EV-proteins, and EV microRNAs that can be useful to develop novel diagnostic algorithms to detect, confirm, or follow up the PA. Moreover, the study of EVs in the field of PA provides further insight in the pathophysiological mechanism of the PA disease.
- Published
- 2021
16. Cortisol resistance in the degu (Octodon degus)
- Author
-
Yi-Zhou, Yao, Francine E, Brennan, Cristian A, Carvajal, Andrea, Vecchiola, Alejandra, Tapia-Castillo, Carlos E, Fardella, and Peter J, Fuller
- Subjects
Pharmacology ,Hydrocortisone ,Guinea Pigs ,Organic Chemistry ,Clinical Biochemistry ,Ligands ,Biochemistry ,Octodon ,Receptors, Glucocorticoid ,Endocrinology ,Animals ,Female ,Amino Acids ,Molecular Biology - Abstract
Cortisol resistance has also been reported in the degu, Octodon degus, a New World hystricomorph endemic to central Chile. The degu is used as a model for studies of stress and diurnal rhythms, parental behaviour and female masculinization. Another New World hystricomorph, the guinea pig, also exhibits glucocorticoid resistance, a result of amino acid sequences that differ from other mammalian glucocorticoid receptors (GR). Mutations in the ligand-binding domain of the human GR have been identified in familial or sporadic generalised cortisol resistance as have variants in the guinea pig. To address the possibility that the high levels of cortisol observed in the degu are a result of the same or similar sequence variations observed in the guinea pig GR, we have cloned, expressed and characterised the ligand-binding domain (LBD) of the degu GR. Somewhat unexpectedly, neither the amino acids nor the region involved in the resistance observed in the guinea pig GR are relevant in the degu GR. The relative resistance to cortisol observed in the degu GR is conferred by the substitution of two isoleucine residues, which are highly conserved in the GR across species, with a valine doublet. These amino acids lie in the region between helices 5 and 6 of the GR LBD, a region known to be important in determining the affinity of ligand-binding in steroid receptors.
- Published
- 2022
17. Aldosterone and Renin Concentration Abnormally Elevated in a Cohort of Normotensive Pregnant Women
- Author
-
Valentina Pasten, ALEJANDRA TAPIA-CASTILLO, Carlos E. Fardella, Andrea Leiva, and Cristian A. Carvajal
- Abstract
During pregnancy the renin-angiotensin-aldosterone system (RAAS) undergo major changes to preserve normal blood pressure (BP), placenta blood flow and ensure a good pregnancy outcome. Abnormal aldosterone-renin metabolism is a risk factor for arterial hypertension and cardiovascular risk, but its association to pathological conditions in pregnancy remains unknown. Hence, clinical and subclinical novel biomarkers associated to these pathological conditions are encouraged to be identified. Aim: To study a cohort of normotensive pregnant women according to their serum aldosterone and plasma renin levels and assay their small extracellular vesicles (sEV) and a specific protein-cargo (LCN2, AT1R). Methods: A cohort of 54 normotensive pregnant women at term gestation. We determined the BP, serum aldosterone and plasma renin concentration. In a subgroup, we isolated their plasma sEVs and semi-quantify two EV-proteins (AT1R, LCN2). Results: We set a normal range of aldosterone and renin based in the interquartile range. We identified 5/54(9%) pregnant women with elevated aldosterone and low renin levels, and 5/54(9%) other pregnant women with low aldosterone and elevated renin levels. No differences were found in sEV-LCN2 nor sEV-AT1R. Conclusion: We found 18% normotensive pregnant women having either high aldosterone or high renin levels, suggesting a subclinical status similar to a primary aldosteronism or a hyperreninemia. Both would evolve to pathological conditions in presence a second challenge affecting the maternal vascular physiology or the BP. sEVs and its specific cargo are encouraged to be further studied in order to clarify its role as potential biomarkers of RAAS alterations in pregnant women.
- Published
- 2021
18. Aldosterone and renin concentrations were abnormally elevated in a cohort of normotensive pregnant women
- Author
-
Valentina, Pastén, Alejandra, Tapia-Castillo, Carlos E, Fardella, Andrea, Leiva, and Cristian A, Carvajal
- Subjects
Renin-Angiotensin System ,Pregnancy ,Placenta ,Hypertension ,Renin ,Pregnancy Outcome ,Humans ,Blood Pressure ,Female ,Pregnant Women ,Aldosterone - Abstract
During pregnancy, the renin-angiotensin-aldosterone system (RAAS) undergoes major changes to preserve normal blood pressure (BP) and placental blood flow and to ensure a good pregnancy outcome. Abnormal aldosterone-renin metabolism is a risk factor for arterial hypertension and cardiovascular risk, but its association with pathological conditions in pregnancy remains unknown. Moreover, potential biomarkers associated with these pathological conditions should be identified.To study a cohort of normotensive pregnant women according to their serum aldosterone and plasma renin levels and assay their small extracellular vesicles (sEVs) and a specific protein cargo (LCN2, AT1R).A cohort of 54 normotensive pregnant women at term gestation was included. We determined the BP, serum aldosterone, and plasma renin concentrations. In a subgroup, we isolated their plasma sEVs and semiquantitated two EV proteins (AT1R and LCN2).We set a normal range of aldosterone and renin based on the interquartile range. We identified 5/54 (9%) pregnant women with elevated aldosterone and low renin levels and 5/54 (9%) other pregnant women with low aldosterone and elevated renin levels. No differences were found in sEV-LCN2 or sEV-AT1R.We found that 18% of normotensive pregnant women had either high aldosterone or high renin levels, suggesting a subclinical status similar to primary aldosteronism or hyperreninemia, respectively. Both could evolve to pathological conditions by affecting the maternal vascular and renal physiology and further the BP. sEVs and their specific cargo should be further studied to clarify their role as potential biomarkers of RAAS alterations in pregnant women.
- Published
- 2021
19. Extending the endocrine hypertension spectrum: novel nonclassic apparent mineralocorticoid excess
- Author
-
Cristian A, Carvajal, Alejandra, Tapia-Castillo, and Carlos E, Fardella
- Subjects
Mineralocorticoid Excess Syndrome, Apparent ,Hypertension ,Humans - Published
- 2021
20. Plasminogen Activator Inhibitor-1 and Adiponectin Are Associated With Metabolic Syndrome Components
- Author
-
Andrea Vecchiola, Alexis M. Kalergis, Cristian A. Carvajal, Killen Garcia, Carlos E. Fardella, Luis M González-Gómez, Rene Baudrand, Alejandra Tapia-Castillo, and Rocio Artigas
- Subjects
Adult ,medicine.medical_specialty ,Waist ,Population ,Adipose tissue ,Adipokine ,Internal medicine ,Plasminogen Activator Inhibitor 1 ,Internal Medicine ,medicine ,Humans ,education ,Metabolic Syndrome ,education.field_of_study ,Adiponectin ,business.industry ,medicine.disease ,Obesity ,Endocrinology ,Blood pressure ,Cross-Sectional Studies ,Matrix Metalloproteinase 2 ,Metabolic syndrome ,business ,Biomarkers - Abstract
BACKGROUND We aimed to study the associations of adipocytokines, endothelial damage markers, and high-sensitivity C-reactive protein (hs-CRP) with metabolic syndrome (MetS) components. METHODS This cross-sectional study included 202 subjects categorized into MetS and No-MetS according to Harmonizing Adult Treatment Panel III. RESULTS Subjects with MetS showed higher levels of proinflammatory molecules but significantly lower adiponectin levels than subjects with No-MetS. Among the studied adipocytokines, plasminogen activator inhibitor-1 (PAI-1) and adiponectin showed the strongest associations with most MetS components. PAI-1 was associated with MetS (odds ratio (OR) 1.107 (1.065–1.151), P < 0.0001), whereas adiponectin was inversely associated with MetS (OR 0.710 (0.610–0.825), P < 0.0001). Following adjustment by sex, age, body mass index, and 24-hour urinary sodium excretion in a multivariate analysis, the association of PAI-1 (OR 1.090 (1.044–1.137), P < 0.0001) and adiponectin (OR 0.634 (0.519–0.775), P < 0.0001) with MetS remained significant. Multivariate analyses supported a model in which systolic blood pressure (BP) could be predicted by PAI-1, hs-CRP, and matrix metalloproteinase 2 (R2 = 0.125; P = 0.04); diastolic BP (R2 = 0.218; P = 0.0001) and glucose (R2 = 0.074; P = 0.0001) could be predicted by PAI-1; waist circumference could be predicted by PAI-1 and hs-CRP (R2 = 0.28; P = 0.016). Receiver operating characteristic curve analysis showed that a PAI-1 concentration had the best sensitivity and specificity for discriminating subjects with MetS. CONCLUSION PAI-1 and adiponectin rendered the most robust associations with MetS components in a general population, indicating that unfavorable adipose tissue performance is a key contributor to these metabolic anomalies. Further prospective analyses should allow establishing whether these adipocytokines can anticipate the progress of MetS and cardiovascular risk.
- Published
- 2021
21. Extracellular vesicles regulate purinergic signaling and epithelial sodium channel expression in renal collecting duct cells
- Author
-
Eric R Barros Lamus, Cristian A. Carvajal, Fons A. J. van de Loo, Juan Pablo Rigalli, René J. M. Bindels, Christine R S de Vries, Femke Witsel, Onno J. Arntz, Joost G. J. Hoenderop, and Valentina Carotti
- Subjects
0301 basic medicine ,Epithelial sodium channel ,Cell type ,ATPase ,Biochemistry ,Extracellular Vesicles ,03 medical and health sciences ,Adenosine Triphosphate ,0302 clinical medicine ,Downregulation and upregulation ,Hyperaldosteronism ,Genetics ,Extracellular ,Humans ,Epithelial Sodium Channels ,Molecular Biology ,G alpha subunit ,biology ,Chemistry ,Epithelial Cells ,Purinergic signalling ,Microvesicles ,Cell biology ,Kidney Tubules ,030104 developmental biology ,Renal disorders Radboud Institute for Molecular Life Sciences [Radboudumc 11] ,Gene Expression Regulation ,biology.protein ,030217 neurology & neurosurgery ,Inflammatory diseases Radboud Institute for Molecular Life Sciences [Radboudumc 5] ,Biotechnology - Abstract
Contains fulltext : 232627.pdf (Publisher’s version ) (Open Access) Purinergic signaling regulates several renal physiological and pathophysiological processes. Extracellular vesicles (EVs) are nanoparticles released by most cell types, which, in non-renal tissues, modulate purinergic signaling. The aim of this study was to investigate the effect of EVs from renal proximal tubule (HK2) and collecting duct cells (HCD) on intra- and intersegment modulation of extracellular ATP levels, the underlying molecular mechanisms, and the impact on the expression of the alpha subunit of the epithelial sodium channel (αENaC). HK2 cells were exposed to HK2 EVs, while HCD cells were exposed to HK2 and HCD EVs. Extracellular ATP levels and αENaC expression were measured by chemiluminescence and qRT-PCR, respectively. ATPases in EV populations were identified by mass spectrometry. The effect of aldosterone was assessed using EVs from aldosterone-treated cells and urinary EVs (uEVs) from primary aldosteronism (PA) patients. HK2 EVs downregulated ectonucleoside-triphosphate-diphosphohydrolase-1 (ENTPD1) expression, increased extracellular ATP and downregulated αENaC expression in HCD cells. ENTPD1 downregulation could be attributed to increased miR-205-3p and miR-505 levels. Conversely, HCD EVs decreased extracellular ATP levels and upregulated αENaC expression in HCD cells, probably due to enrichment of 14-3-3 isoforms with ATPase activity. Pretreatment of donor cells with aldosterone or exposure to uEVs from PA patients enhanced the effects on extracellular ATP and αENaC expression. We demonstrated inter- and intrasegment modulation of renal purinergic signaling by EVs. Our findings postulate EVs as carriers of information along the renal tubules, whereby processes affecting EV release and/or cargo may impact on purinergically regulated processes.
- Published
- 2021
22. Proteomic Profile of Urinary Extracellular Vesicles Identifies AGP1 as a Potential Biomarker of Primary Aldosteronism
- Author
-
René J. M. Bindels, Morag J. Young, Andrea Vecchiola, Eric Barros, Carlos E. Fardella, Alejandra Tapia-Castillo, Cristian A. Carvajal, Juan Pablo Rigalli, and Joost G. J. Hoenderop
- Subjects
0301 basic medicine ,Adult ,Male ,Proteomics ,medicine.medical_specialty ,Context (language use) ,Urine ,030204 cardiovascular system & hematology ,03 medical and health sciences ,chemistry.chemical_compound ,Extracellular Vesicles ,Young Adult ,0302 clinical medicine ,Endocrinology ,Primary aldosteronism ,All institutes and research themes of the Radboud University Medical Center ,Internal medicine ,Hyperaldosteronism ,medicine ,Humans ,Aged ,Creatinine ,Proteomic Profile ,Aldosterone-to-renin ratio ,Chemistry ,Area under the curve ,Orosomucoid ,Middle Aged ,medicine.disease ,030104 developmental biology ,Renal disorders Radboud Institute for Molecular Life Sciences [Radboudumc 11] ,Female ,Biomarkers - Abstract
ContextPrimary aldosteronism (PA) represents 6% to 10% of all essential hypertension patients and is diagnosed using the aldosterone-to-renin ratio (ARR) and confirmatory studies. The complexity of PA diagnosis encourages the identification of novel PA biomarkers. Urinary extracellular vesicles (uEVs) are a potential source of biomarkers, considering that their cargo reflects the content of the parent cell.ObjectiveWe aimed to evaluate the proteome of uEVs from PA patients and identify potential biomarker candidates for PA.MethodsSecond morning spot urine was collected from healthy controls (n = 8) and PA patients (n = 7). The uEVs were isolated by ultracentrifugation and characterized. Proteomic analysis on uEVs was performed using LC-MS Orbitrap.ResultsIsolated uEVs carried extracellular vesicle markers, showed a round shape and sizes between 50 and 150 nm. The concentration of uEVs showed a direct correlation with urinary creatinine (r = 0.6357; P = 0.0128). The uEV size mean (167 ± 6 vs 183 ± 4nm) and mode (137 ± 7 vs 171 ± 11nm) was significantly smaller in PA patients than in control subjects, but similar in concentration. Proteomic analysis of uEVs from PA patients identified an upregulation of alpha-1-acid glycoprotein 1 (AGP1) in PA uEVs, which was confirmed using immunoblot. A receiver operating characteristic curve analysis showed an area under the curve of 0.92 (0.82 to 1; P = 0.0055).ConclusionProteomic and further immunoblot analyses of uEVs highlights AGP1 as potential biomarker for PA.
- Published
- 2020
23. [Testosterone inhibits human wild-type and chimeric aldosterone synthase activity in vitro]
- Author
-
Andrea, Vecchiola, Cristóbal A, Fuentes, Cristian A, Carvajal, Carmen, Campino, Fidel, Allende, Alejandra, Tapia-Castillo, Carlos F, Lagos, and Carlos E, Fardella
- Subjects
HEK293 Cells ,Tandem Mass Spectrometry ,Cytochrome P-450 CYP11B2 ,Humans ,Testosterone ,Aldosterone - Abstract
Familial hyperaldosteronism type I is caused by the generation of a chimeric aldosterone synthase enzyme (ASCE) which is regulated by ACTH instead of angiotensin II. We have reported that in vitro, the wild-type (ASWT) and chimeric aldosterone synthase (ASCE) enzymes are inhibited by progesterone and estradiol does not affect their activity.To explore the direct action of testosterone on ASWT and ASCE enzymes.HEK-293 cells were transiently transfected with vectors containing the full ASWT or ASCE cDNAs. The effect of testosterone on AS enzyme activities was evaluated incubating HEK-cells transfected with enzyme vectors and adding deoxycorticosterone (DOC) alone or DOC plus increasing doses of testosterone. Aldosterone production was measured by HPLC-MS/MS. Docking of testosterone within the active sites of both enzymes was performed by modelling in silico.In this system, testosterone inhibited ASWT (90% inhibition at five pM, 50% inhibitory concentration (IC50) =1.690 pM) with higher efficacy andpotency than ASCE (80% inhibition at five pM, IC50=3.176 pM). Molecular modelling studies showed different orientation of testosterone in ASWT and ASCE crystal structures.The inhibitory effect of testosterone on ASWT or ASCE enzymes is a novel non-genomic testosterone action, suggesting that further clinical studies are needed to assess the role of testosterone in the screening and diagnosis of primary aldosteronism.
- Published
- 2020
24. Relationship Between Metabolic Syndrome Components and Proinflammatory Molecules
- Author
-
Andrea Vecchiola, Carlos E. Fardella, Alejandra Tapia-Castillo, Rene Baudrand, Alexis M. Kalergis, Killen Garcia, Cristian A. Carvajal, Luis-Martin González-Gómez, and Rocio Artigas
- Subjects
Chemistry ,Endocrinology, Diabetes and Metabolism ,Immunology ,medicine ,Metabolic syndrome ,medicine.disease ,Proinflammatory cytokine - Abstract
We aimed to study the associations of 5 adipocytokines, two endothelial damage markers, and hs-CRP with the MetS components to distinguish the most significant cytokines likely related to distinct metabolic profiles. Methods: Cross-sectional study with 202 Chilean subjects (18–65 years old), categorized by MetS, and No-MetS according to Harmonizing ATP III. Adipocytokines profiling included adiponectin, leptin, hs-CRP, CTRP-1, PAI-1, FABP4, and metalloproteinase (MMP)-9 and MMP-2 activity. Results: Subjects with MetS showed higher levels of the most proinflammatories molecules but significantly lower adiponectin than subjects with No-MetS. Among the studied adipocytokines, PAI-1 and adiponectin showed the strongest associations with most of MetS components. PAI-1 was associate with MetS OR 1.107 [1.065–1.151], p< 0.0001, and adiponectin inversely associated with MetS OR 0.710 [0.610 -0.825], p< 0.0001). Following adjustment by sex, age, BMI, and 24 h sodium urinary excretion in a multivariate analysis, the association of PAI-1 OR 1.090 [1.044–1.137], p< 0.0001) and adiponectin OR 0.634 [0.519 - 0.775], p < 0.0001) with MetS remained significant. Multivariate analyses support a model where PAI-1associate to waist_hip, SBP, DBP, and glucose (all p< 0.0001) and adiponectin associate to TG (p=0.03) and HDL-cholesterol (p=0.0001). Conclusion: PAI-1 and Adiponectin rendered the most robust associations with MetS components in a general population, indicating that unfavourable adipose tissue performance is a key contributor to these metabolic anomalies. Further prospective analyses should allow establishing whether these adipocytokines can anticipate the progress of MetS and cardiovascular risk. Conflict of interest: The authors declared no conflict of interest. Funding: This work was supported by Chilean grants CONICYT Fondo Nacional de Desarrollo Científico y Tecnológico, (FONDECYT) 1160695(CEF) and 1190419(RB); FONDECYT Post-doctorado 3200646(ATC); Millenium Institute of Immunology and Immunotherapy - ICM (P09/16-F)(AK-CEF).
- Published
- 2021
25. Testosterone inhibits human wild-type and chimeric aldosterone synthase activity in vitro
- Author
-
Andrea Vecchiola, Cristóbal A. Fuentes, Cristian A. Carvajal, Carmen Campino, Fidel Allende, Alejandra Tapia-Castillo, Carlos F. Lagos, and Carlos Fardella
- Abstract
BackgroundFamilial hyperaldosteronism type I is caused by the generation of a chimeric aldosterone synthase enzyme (ASCE) which is regulated by ACTH instead of angiotensin II. We have reported that in vitro, the wild-type (ASWT) and chimeric aldosterone synthase (ASCE) enzymes are inhibited by progesterone and estradiol did not affect.AimTo explore the direct action of testosterone on ASWT and ASCE enzymes.MethodsHEK-293 cells were transiently transfected with vectors containing the full ASWT or ASCE cDNAs. The effect of testosterone on AS enzyme activities were evaluated incubating HEK-cells transfected with enzymes vectors and adding deoxycorticosterone (DOC) alone or DOC plus increasing doses of testosterone. Aldosterone production was measured by HPLC-MS/MS. Docking of testosterone within the active sites of both enzymes was performed.ResultsIn this system, testosterone inhibited ASWT (90% inhibition at five µM, IC50=1.690 µM) with higher efficacy and potency than ASCE (80% inhibition at five µM, IC50=3.176 µM). Molecular modelling studies showed different orientation of testosterone in ASWT and ASCE crystal structures.ConclusionsThe inhibitory effect of testosterone on ASWT or ASCE enzymes is a novel non-genomic testosterone action, suggesting that further clinical studies are needed to assess the role of testosterone in the screening and diagnosis of primary aldosteronism.
- Published
- 2020
26. Comparing Approaches to Normalize, Quantify, and Characterize Urinary Extracellular Vesicles
- Author
-
Omar A. Z. Tutakhel, Marian C. Clahsen-van Groningen, Cristian A. Carvajal, René J. M. Bindels, Thierry P P van den Bosch, David Severs, Juan Pablo Rigalli, Robert A. Fenton, Roger Carles-Fontana, Cathy A Cuevas, Joost G. J. Hoenderop, Charles J. Blijdorp, Ewout J. Hoorn, Martijn H van Heugten, Rob Willemsen, Fons A. J. van de Loo, Usha M. Musterd-Bhaggoe, Martin E. van Royen, Onno J. Arntz, Eric Barros, Thomas A Hartjes, Guido Jenster, Internal Medicine, Pathology, Clinical Genetics, and Urology
- Subjects
Adult ,Male ,Tamm–Horsfall protein ,Urinary system ,Nanoparticle tracking analysis ,Nephron ,Urine ,Urinalysis ,Excretion ,chemistry.chemical_compound ,Extracellular Vesicles ,All institutes and research themes of the Radboud University Medical Center ,medicine ,Humans ,Creatinine ,Chromatography ,biology ,CD63 ,Chemistry ,Editorials ,Reproducibility of Results ,Metabolic Disorders Radboud Institute for Molecular Life Sciences [Radboudumc 6] ,General Medicine ,Renal disorders Radboud Institute for Molecular Life Sciences [Radboudumc 11] ,medicine.anatomical_structure ,Nephrology ,Case-Control Studies ,biology.protein ,Female ,Kidney Diseases ,Inflammatory diseases Radboud Institute for Molecular Life Sciences [Radboudumc 5] ,Biomarkers - Abstract
Background Urinary extracellular vesicles (uEVs) are a promising source for biomarker discovery, but optimal approaches for normalization, quantification, and characterization in spot urines are unclear. Methods Urine samples were analyzed in a water-loading study, from healthy subjects and patients with kidney disease. Urine particles were quantified in whole urine using nanoparticle tracking analysis (NTA), time-resolved fluorescence immunoassay (TR-FIA), and EVQuant, a novel method quantifying particles via gel immobilization. Results Urine particle and creatinine concentrations were highly correlated in the water-loading study (R2 0.96) and in random spot urines from healthy subjects (R2 0.47-0.95) and patients (R2 0.41-0.81). Water loading reduced aquaporin-2 but increased Tamm-Horsfall protein (THP) and particle detection by NTA. This finding was attributed to hypotonicity increasing uEV size (more EVs reach the NTA size detection limit) and reducing THP polymerization. Adding THP to urine also significantly increased particle count by NTA. In both fluorescence NTA and EVQuant, adding 0.01% SDS maintained uEV integrity and increased aquaporin-2 detection. Comparison of intracellular- and extracellular-epitope antibodies suggested the presence of reverse topology uEVs. The exosome markers CD9 and CD63 colocalized and immunoprecipitated selectively with distal nephron markers. Conclusions uEV concentration is highly correlated with urine creatinine, potentially replacing the need for uEV quantification to normalize spot urines. Additional findings relevant for future uEV studies in whole urine include the interference of THP with NTA, excretion of larger uEVs in dilute urine, the ability to use detergent to increase intracellular-epitope recognition in uEVs, and CD9 or CD63 capture of nephron segment-specific EVs.
- Published
- 2020
27. SAT-590 Role of Adipocyte Hyperplasia and Hypertrophy in the Release and Charge of Exosomes in Human Fat Cells
- Author
-
Mauricio Cuello, Cristian A. Carvajal, Andrea Vecchiola, Maria Cristina Goens, Francisca Liberona, Alejandra Tapia-Castillo, Carlos E. Fardella, and Sumie Kato
- Subjects
medicine.medical_specialty ,Human fat ,Adipose Tissue, Appetite, and Obesity ,Chemistry ,Endocrinology, Diabetes and Metabolism ,Hyperplasia ,medicine.disease ,Microvesicles ,Muscle hypertrophy ,chemistry.chemical_compound ,Endocrinology ,Adipose Tissue Biology and Obesity ,Internal medicine ,Adipocyte ,medicine ,AcademicSubjects/MED00250 - Abstract
In obesity, the increase in the number and / or size of adipocytes leads to chronic low-grade systemic inflammation that conditions the development and evolution of a series of pathologies such as coronary heart disease or cancer. The change from hyperplasia to hypertrophy has been characterized by the expression of early and late adipogenic biomarkers, but little is known about the communications between cells. Exosomes are small extracellular vesicles (30-100 nm in diameter) released by exocytosis in almost all cell types. Due to its wide distribution and absorption by different cell types, exosomes have been considered an attractive tool for diagnosis, therapy and response evaluation. Objective: To characterize the exosomes released by human fat cells during differentiation and the effect of hyperplasia on the function of these. Material and methods: Human cells (SW-872) were cultured for 24h in DMEM-F12- with FBS serum (free of steroids and exosomes), differentiated with adipogenic cocktail for 7 days, and hypertrophy for further 24h G1 agonist treatment. Exosomes were isolated from conditioned medium of SW872 cells by ultracentrifugation and characterized by immunoblotting against exosomal markers, (Nanoparticle Tracking Analysis (NTA) and transmission electron microscopy (TEM). Cancer initiating cells (CICs) were isolated from HeyA8 ovarian cancer cells using culture selecting conditions. CICs were 24h treated with exosomes (1x1011 particles/mL) and then seeded over matrigel to carry out 3Dmigration assays. Results: SW872 cells showed the morphological characteristics described for this cell line and MR expression was observed. Successful isolation of SW872-derived exosomes was confirmed by assessing the particle size distribution by NTA, the morphology by TEM and the presence of exosome markers (Alix, HSP70, TSG101, and CD36) by immunoblotting. Preadipocyte differentiation showed a significant decrease in the exosome concentration (pre,1.3x1011 particles/ml vs adipo, 1.5x1010 particles/ml p
- Published
- 2020
28. Modeling of university dropout using Markov chains
- Author
-
Juan Elías Aspeé-Chacón, Cristian Manuel Carvajal-Muquillaza, José González-Campos, and Universidad de Playa Ancha
- Subjects
deserção ,General Computer Science ,General Mathematics ,cadenas de Markov ,General Physics and Astronomy ,02 engineering and technology ,educación superior ,dropout ,General Biochemistry, Genetics and Molecular Biology ,[MATH.MATH-ST]Mathematics [math]/Statistics [math.ST] ,Political science ,0202 electrical engineering, electronic engineering, information engineering ,abandono de estudios ,deserción ,Chile ,lcsh:Science ,lcsh:Science (General) ,Markov chains ,4. Education ,05 social sciences ,050301 education ,General Social Sciences ,educação superior ,General Chemistry ,abandono de estudos ,[STAT]Statistics [stat] ,higher education ,General Earth and Planetary Sciences ,cadeias de Markov ,020201 artificial intelligence & image processing ,lcsh:Q ,General Agricultural and Biological Sciences ,0503 education ,Humanities ,lcsh:Q1-390 - Abstract
International audience; Access to higher education is only a first step in achieving equity in education; the following step is improving student retention, or lowering dropout rates, which is the same thing. The present study focused on the definition of an index as an estimator of the risk of individuals dropping out of a university using a Markov chain model, based on the randomness of the occurrence of dropping out. The suggested index was applied to a sample of 5,700 university students from the 2012-2015 annual cohorts of 8 university departments of a public regional university in Chile. The results indicate that the highest average probability of dropping out (slightly more than 39%) occurs in the first 2 semesters of university studies, and then decreases through time. This indicates the need for institutional retention policies that pay particular attention to the first year of university studies. Having this index also allows a formal estimation of changes or temporary variations in the risk, as well as quantifying the impact of interventions, not only for the case under study but for the entire higher education system.; El acceso a la educación superior es solo un primer paso a la equidad educativa, el siguiente es lograr la retención del estudiante o, lo que es lo mismo, evitar su deserción. Esta propuesta se centra en la definición de un índice como estimador del riesgo a la deserción individual, utilizando en tal modelación las cadenas de Markov, con base en la aleatoriedad de la ocurrencia del fenómeno de la deserción. El índice sugerido se aplica a una muestra de 5700 estudiantes universitarios de las cohortes anuales 2012-2015 de 8 facultades, todas ellas pertenecientes a una universidad pública y regional de Chile. Los resultados indican que las mayores probabilidades de deserción se presentan en los 2 primeros semestres de estudios, con una probabilidad promedio superior al 39 %, que luego disminuye a lo largo de los años. Esto obliga a las políticas institucionales a una fuerte inversión focalizada en el primer año. Asimismo, disponer de este índice permite una estimación formal para cambios o variaciones temporales del riesgo y cuantificar el impacto de las intervenciones, no solo para el caso en estudio, sino para todo el sistema de educación superior.; O acesso ao ensino superior é apenas um primeiro passo para a equidade educacional, o próximo é alcançar a retenção de estudantes ou, o que é o mesmo, evitar a sua deserção. Esta proposta se enfoca na definição de um índice como um estimador do risco de deserção individual, usando cadeias de Markov em tal modelagem, baseado na aleatoriedade da ocorrência do fenômeno da deserção. O índice sugerido é aplicado a uma amostra de 5700 estudantes universitários das coortes anuais de oito faculdades de 2012-2015, todas pertencentes a uma universidade pública e regional do Chile. Os resultados indicam que as maiores probabilidades de abandono ocorrem nos dois primeiros semestres de estudo, com uma probabilidade média superior a 39%, diminuindo ao longo dos anos. Isso força as políticas institucionais a um forte investimento focado no primeiro ano. Da mesma forma, possuir esse índice permite uma estimativa formal para mudanças ou variações temporárias do risco e quantificar o impacto das intervenções, não apenas para o caso em estudo, mas para todo o sistema de ensino superior.
- Published
- 2020
29. Urinary sodium-to-potassium ratio and plasma renin and aldosterone concentrations in normotensive children: implications for the interpretation of results
- Author
-
Carlos E. Fardella, Sofia Sifaqui, Maria Rodriguez-Fernandez, Ivonne D'Apremont, Hernan Garcia, Rene Baudrand, Rosario Moore, Claudia Trincado, Jose Tomas Ossa, Fidel Allende, Monica Arancibia, Sandra Solari, Carmen Campino, Helena Poggi, Alejandro Martinez-Aguayo, Cristian A. Carvajal, and Soledad Peredo
- Subjects
Male ,medicine.medical_specialty ,Physiology ,Urinary system ,Potassium ,chemistry.chemical_element ,Blood Pressure ,Urine ,030204 cardiovascular system & hematology ,Plasma renin activity ,Renin-Angiotensin System ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Internal medicine ,Renin ,Internal Medicine ,Medicine ,Humans ,030212 general & internal medicine ,Child ,Aldosterone ,business.industry ,Sodium ,Gestational age ,Nomogram ,Healthy Volunteers ,Blood pressure ,Endocrinology ,chemistry ,Child, Preschool ,Female ,Cardiology and Cardiovascular Medicine ,business - Abstract
OBJECTIVES To identify associations among the plasma renin concentration (PRC), plasma aldosterone and urinary sodium (Na)/potassium (K) ratio, and to integrate these variables into a nomogram with the aim of estimating the expected versus observed aldosterone concentration. METHODS We studied 40 healthy normotensive children (5-8 years old, 57.5% girls) who were born at term and were adequate for their gestational age. Following overnight fasting, the PRC and plasma aldosterone in blood samples were measured, and the Na/K ratio was calculated from a simultaneously obtained urinary spot sample. A mathematical function was defined with these three variables, and a nomogram was built that would return the expected aldosterone concentration from the obtained plasma renin and urinary Na/K ratio values. RESULTS The PRC (B = 5.9, P
- Published
- 2019
30. Downregulation of exosomal miR-192-5p and miR-204-5p in subjects with nonclassic apparent mineralocorticoid excess
- Author
-
Andrew Lai, Dominic Guanzon, Carlos Salomon, Carlos Palma, Carlos E. Fardella, Alejandra Tapia-Castillo, Eric Barros, Andrea Vecchiola, Fidel Allende, and Cristian A. Carvajal
- Subjects
Adult ,Male ,medicine.medical_specialty ,Adolescent ,Urinary system ,Mineralocorticoid receptor ,Population ,lcsh:Medicine ,Down-Regulation ,Exosomes ,General Biochemistry, Genetics and Molecular Biology ,Excretion ,chemistry.chemical_compound ,Young Adult ,Internal medicine ,medicine ,Humans ,education ,Child ,education.field_of_study ,Aldosterone ,business.industry ,Research ,Mineralocorticoid Excess Syndrome, Apparent ,lcsh:R ,Reproducibility of Results ,MicroRNA ,General Medicine ,Middle Aged ,Phenotype ,Nonclassic AME ,MicroRNAs ,Endocrinology ,Blood pressure ,chemistry ,Case-Control Studies ,Hypertension ,Female ,Cortisone ,business ,medicine.drug - 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 Conclusions These findings could support a potential role of these miRNAs as regulators and novel biomarkers of the NC-AME phenotype.
- Published
- 2019
31. Sobre-duración: una Aproximación Cuantitativa
- Author
-
Claudia A. Tassara, María Jesús Suárez Álvarez, José González, and Cristian M. Carvajal
- Subjects
Sociology ,First order ,Humanities ,Education - Abstract
espanolSe presenta un estudio sobre la titulacion oportuna, un problema de gran interes para las instituciones de educacion superior. En el proceso de organizar la investigacion, se toma como concepto basal lo denominado sobre-duracion, en donde la titulacion oportuna se transforma en un caso particular. Se propone un modelo predictivo para la sobre-duracion aplicado a un conjunto real de datos de una institucion de educacion superior. Se establecen los niveles de significancia de las variables caracterizadas como predictoras, ademas de variaciones porcentuales por unidad de cambio en ellas. Para facilitar el estudio de la dependencia jerarquica, se estructura una metodologia de representacion denominada raiz jerarquica de tercer orden, que permite cuantificar los efectos y su nivel de implicancia. Como consecuencia de esto se pudo establecer que la sobre-duracion puede ser explicada por un conjunto de variables de primer orden, tales como genero, ano de egreso de la ensenanza media, grupo de dependencia del colegio, promocion, cargo del profesor guia de tesis, entre otras, de las cuales muchas de ellas no pueden ser perturbadas de forma directa. EnglishA study on timely qualification is presented, a problem of great interest for higher education institutions. In the process of organizing research, the so-called over-duration is taken as the baseline concept, where the appropriate degree is transformed into a particular case. A predictive model for over-duration applied to a real data set of a higher education institution is determined. The levels of significance of the variables characterized as predictors are established, as well as percentage variations per unit of change in them. To facilitate the study of hierarchical dependence, a representation methodology called the hierarchical root of the third order is structured, which allows to quantify the effects and their level of implication. As a consequence of this it was established that the over-duration can be explained by a set of variables of first order, such as gender, year of graduation from high school, college dependency group, promotion, position of the teacher thesis guide, among others, of which many of them cannot be directly disturbed.
- Published
- 2018
32. La demostración matemática: significado, tipos, funciones atribuidas y relevancia en el conocimiento profesional de los profesores de matemáticas
- Author
-
Pablo Flores-Martínez, Gabriela Valverde-Soto, and Cristian Alfaro-Carvajal
- Subjects
Secondary education ,General Computer Science ,General Mathematics ,demostración matemática ,General Physics and Astronomy ,Context (language use) ,Mathematical proof ,General Biochemistry, Genetics and Molecular Biology ,Desarrollo del profesor ,análisis conceptual ,demonstração matemática ,Mathematics education ,análisis didáctico ,Public education ,lcsh:Science ,lcsh:Science (General) ,didactic analysis ,Specialized knowledge ,análise didática ,Teórica ,Educación Matemática ,4. Education ,mathematical proof ,math teacher training ,General Social Sciences ,13. Matemáticas escolares ,General Chemistry ,Field (geography) ,conceptual analysis ,análise conceitual ,formação de professores de matemática ,Libros de texto ,General Earth and Planetary Sciences ,lcsh:Q ,Descriptive research ,formación de profesores de matemáticas ,General Agricultural and Biological Sciences ,Desarrollo ,Meaning (linguistics) ,lcsh:Q1-390 - Abstract
Resumen El objetivo de esta investigación es realizar un estudio teórico sobre el significado de la demostración matemática, considerando tres elementos centrales: el concepto, los tipos de demostraciones matemáticas, así como sus funciones. La indagación es de tipo cualitativo de carácter descriptivo. El método empleado para la recolección y el análisis de la información es el análisis conceptual. Se consideraron cuatro fuentes de datos: diccionarios, libros de texto, investigaciones previas y el programa de estudios de matemáticas del Ministerio de Educación Pública de Costa Rica. La técnica de recolección de los datos requeridos fue la revisión bibliográfica. Se determinó que el concepto de demostración tiene diversos sentidos, dependiendo del contexto en el que se ubique; que los tipos de demostraciones matemáticas pueden clasificarse en dos categorías, directas e indirectas, y que existen diferentes funciones atribuidas a las demostraciones matemáticas, las cuales cobran relevancia, dependiendo del ámbito en donde se consideren. Se cree que los tres elementos anteriores deben formar parte del conocimiento especializado del profesor de matemáticas, para que promuevan el sentido de la demostración en los estudiantes de la educación secundaria. Palabras claves: demostración matemática; formación de profesores de matemáticas; análisis conceptual; análisis didáctico. Abstract The objective of this paper is to conduct a theoretical study on the meaning of mathematical proof, taking into consideration three main elements: concept, types, and functions. This is a qualitative and descriptive research. The method used to collect and analyze information is the conceptual analysis. Four sources of information were considered: dictionaries, textbooks, previous research, and the mathematics curriculum of the Ministry of Public Education of Costa Rica. The technique for collecting the information was the bibliographic review. It was determined that proof has different meanings depending on the context; that the types of mathematical proof can be classified into two categories, direct and indirect; and that there are different functions attributed to mathematical proof which are relevant depending on the field in which they are considered. Consequently, the three previous elements should be part of math teachers’ specialized knowledge to promote math proof in secondary education. Keywords: mathematical proof; math teacher training; conceptual analysis; didactic analysis. Resumo O objetivo desta pesquisa é realizar um estudo teórico do significado da demonstração matemática, considerando três elementos centrais: o conceito, os tipos de demonstrações matemáticas e suas funções. A indagação é do tipo qualitativa de caráter descritivo. O método utilizado para a coleta e análise de informações é a análise conceitual. Quatro fontes de dados foram consideradas: dicionários, livros de texto, pesquisas prévias e o programa de estudos de matemática do Ministério da Educação Pública da Costa Rica. A técnica para coleta dos dados solicitados foi a revisão bibliográfica. Determinou-se que o conceito de demonstração tem significados diferentes, dependendo do contexto em que está localizado; que os tipos de demonstrações matemáticas podem ser classificados em duas categorias, diretas e indiretas, e que existem diferentes funções atribuídas a demonstrações matemáticas, as quais se tornam importantes, dependendo da área considerada. Acredita-se que os três elementos acima devem fazer parte do conhecimento especializado do professor de matemática, para promover o sentido de demonstração em alunos do ensino médio. Palavras-chave: demonstração matemática; formação de professores de matemática; análise conceitual; análise didática.
- Published
- 2019
33. Detection of a novel severe mutation affecting the CYP21A2 gene in a Chilean male with salt wasting congenital adrenal hyperplasia
- Author
-
Cristian A. Carvajal, Carlos E. Fardella, Felipe Valenzuela, Carlos F. Lagos, Marcela Lagos, Rene Baudrand, Alejandra Martínez, and Eugenio Arteaga
- Subjects
Infertility ,Adult ,Male ,endocrine system diseases ,Genotype ,Endocrinology, Diabetes and Metabolism ,In silico ,030209 endocrinology & metabolism ,Biology ,urologic and male genital diseases ,medicine.disease_cause ,Polymerase Chain Reaction ,03 medical and health sciences ,0302 clinical medicine ,Endocrinology ,Adrenal insufficiency ,medicine ,Humans ,Congenital adrenal hyperplasia ,Genetic Testing ,Binding site ,Genetic testing ,Genetics ,Mutation ,medicine.diagnostic_test ,Adrenal Hyperplasia, Congenital ,nutritional and metabolic diseases ,medicine.disease ,030220 oncology & carcinogenesis ,Steroid 21-Hydroxylase ,Binding domain - Abstract
21-hydroxylase deficiency (21-OHD) is a congenital adrenal disease with more than 200 mutations published to date. The aim of this report is to describe a severe novel mutation of the CYP21A2 gene. We describe a case of a 39-year-old male diagnosed with a salt wasting congenital adrenal hyperplasia (SWCAH) due to 21-OHD. The genetic testing was done using a combination of three methods (PCR XL, SALSA-MLPA, and bidirectional sequencing) and finally an in silico analysis. The genetic testing demonstrated three severe mutations of the CYP21A2 gene (p.Gln318*; c.290-13C>G; and p.Trp86*), being the last one a novel mutation not previously reported. The in silico modeling of the p.Trp86* (c.258G>A) showed a truncated CYP21A2 protein that loses all the main structural features required for activity, such as the HEM binding domain and the hormone binding site. We present an adult man with an SWCAH due to 21-OHD who carried three severe mutations of the CYP21A2 gene, one of them, p.Trp86* (c.258G>A) has not been previously described.
- Published
- 2019
34. SAT-LB012 Differential miRNA-Transcriptomic and Proteomic Profile in Urinary Exosomes of Subjects with 'Nonclassic' Apparent Mineralocorticoid Excess Syndrome
- Author
-
Andrea Vecchiola, Cristian A. Carvajal, Carmen Campino, Alejandra Tapia, Carlos Salomon, Carlos E. Fardella, Rene Baudrand, Eric Barros, and Fidel Allende
- Subjects
Transcriptome ,Proteomic Profile ,RAA System and Endocrine Hypertension ,Endocrinology, Diabetes and Metabolism ,Urinary system ,microRNA ,medicine ,Apparent mineralocorticoid excess syndrome ,Computational biology ,Biology ,medicine.disease ,Microvesicles ,Cardiovascular Endocrinology - Abstract
Mineralocorticoid arterial hypertension has risen as one of the most prevalent causes of secondary hypertension, where 11β-hydroxysteroid dehydrogenase type-2 partial deficiency (also known as non-classical AME (NC-AME)), could reach a prevalence of 7% in Chilean subjects. The phenotype of NC-AME is associated to high serum cortisol (F) to cortisone (E) ratio &low E, high potassium excretion and low-renin activity (Tapia-Castillo et al, JCEM 2018). However, local metabolic changes in NC-AME affecting protein, RNA and miRNA expression have not been studied. Nowadays, exosomes technology allows to identify those biomolecules in specific biofluids. Aim: To identify the transcriptomic (miRNA) and proteomic profile in urinary exosomes of subjects with non-classical AME and healthy subjects. Subjects and methods: A cross-sectional study was carried out in 24 subjects (10-65 years). The subjects were classified as NC-AME (F/E ratio> percentile 75th, and E < percentile 25th) and healthy controls. The levels of F, E, aldosterone and plasma renin activity were quantified. The exosomes were obtained from morning urine samples by differential ultracentrifugation and were characterized with the NS300 nanoparticle analyzer, electron microscopy and western-blot for CD63 and TSG101. The total exosomal RNA was isolated with Trizol reagent. The Illumina TruSeq Small RNA kit was used and sequenced by Illumina NextSeq-500. Additionally, an exosomal proteomic profile was obtained by LC-MS/MS 5600 Triple TOF (ABSciex, Framingham, USA). Bioinformatic analyzes were performed with miRdeep2, PANTHER and STRING. Results: In urinary exosomes, we found355 from 2822 predicted miRNAs , of which 170 miRNA were found to be upregulated and 185 miRNA were dowregulated in subjects with NC-AME vs controls. We also found miR-204-5p (change times = 0.115; p = 0.001) and have miR-192-5p (change times = 0.246; p = 0.03), present a significantly lower expression in NC-AME subjects vs controls, both confirmed by Taqman PCR. Genetic ontology analyses indicate that both miRNAs would have a role in steroid biosynthesis (hsa00100). We identified around 350 exosomal proteins, of which 79 proteins were commonly expressed in both groups and 23 proteins were exclusively expressed in subjects with NC-AME, highlighting the 14-3-3 (YWHAE, YWHAZ), RHOA and CDC42 protein. Conclusion: This is the first study on urinary exosomes showing the differential expression of miRNA (miR-204 and miR-192) and proteins (14-3-3, RHOA and CDC42) which highlight its potential role as biomarkers and regulators of the high mineralocorticoid activity in NC-AME subjects. Acknowledgements: This study was supported by grants CONICYT-FONDECYT 1150437, 1160695, 1160836, CONICYT-FONDEQUIP EQM150023, IMII P09/16-F, & CETREN-UC. Unless otherwise noted, all abstracts presented at ENDO are embargoed until the date and time of presentation. For oral presentations, the abstracts are embargoed until the session begins. Abstracts presented at a news conference are embargoed until the date and time of the news conference. The Endocrine Society reserves the right to lift the embargo on specific abstracts that are selected for promotion prior to or during ENDO.
- Published
- 2019
35. The Aldosterone/Renin Ratio Predicts Cardiometabolic Disorders in Subjects Without Classic Primary Aldosteronism
- Author
-
Sandra Solari, Andrea Vecchiola, Roberto Olmos, Eric Barros, Cristobal A. Fuentes, Alexis M. Kalergis, Alejandra Tapia-Castillo, Hernán García, Cristian A. Carvajal, Carmen Campino, Alejandro Martinez-Aguayo, Fidel Allende, Rene Baudrand, and Carlos E. Fardella
- Subjects
Adult ,Male ,medicine.medical_specialty ,medicine.drug_class ,Population ,Blood Pressure ,030204 cardiovascular system & hematology ,Plasma renin activity ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Primary aldosteronism ,Internal medicine ,Renin–angiotensin system ,Hyperaldosteronism ,Renin ,Internal Medicine ,Medicine ,Humans ,030212 general & internal medicine ,Prospective Studies ,education ,Aldosterone ,Metabolic Syndrome ,education.field_of_study ,business.industry ,Odds ratio ,medicine.disease ,Prognosis ,Endocrinology ,Cross-Sectional Studies ,chemistry ,Mineralocorticoid ,Hypertension ,Disease Progression ,Female ,Metabolic syndrome ,business ,Biomarkers - Abstract
BACKGROUND Aldosterone has been linked with obesity, metabolic syndrome (MetS), pro-inflammatory, and prothrombotic states; however, most studies relate these indicators with primary aldosteronism (PA), excluding non-PA patients. OBJECTIVE To determine whether aldosterone, renin, or the plasma aldosterone/renin ratio (ARR) are associated with metabolic disorders and inflammatory/vascular biomarkers in a non-PA population. METHODS We studied 275 patients including adolescents and adults of both genders and measured plasma and urinary aldosterone and determined the plasma renin activity. In all subjects, the presence of MetS was determined according to Adult Treatment Panel III. Renal, vascular, inflammatory, and mineralocorticoid activity biomarkers were evaluated. RESULTS The ARR correlated with the number of variables of MetS (r = 0.191, P = 0.002), body mass index (BMI; r = 0.136, P = 0.026), systolic blood pressure (r = 0.183, P = 0.002), diastolic blood pressure (r = 0.1917, P = 0.0014), potassium excreted fraction (r = 0.174, P = 0.004), low-density lipoprotein (r = 0.156, P = 0.01), plasminogen activator inhibitor type 1 (r = 0.158, P = 0.009), microalbuminuria (r = 0.136, P = 0.029), and leptin (r = 0.142, P = 0.019). In a linear regression model adjusted by age, BMI, and gender, only the ARR was still significant (r = 0.108, P = 0.05). In a logistic regression analysis, the ARR predicted MetS index (odds ratio (OR) = 1.07 [95% confidence interval (CI) = 1.011–1.131], P= 0.02) even after adjusting for age, BMI, and gender. On the other hand, aldosterone showed no association with MetS or inflammatory markers. CONCLUSION These results suggest a continuum of cardiometabolic risk beyond the classic PA threshold screening. The ARR could be a more sensitive marker of obesity, MetS, and endothelial damage in non-PA patients than aldosterone or renin alone. Prospective studies are needed to develop future screening cutoff values.
- Published
- 2019
36. Resolución de problemas en la enseñanza del cálculo diferencial e integral en una variable: Perspectiva de los docentes de matemática
- Author
-
Jennifer Fonseca-Castro and Cristian Alfaro-Carvajal
- Subjects
Single variable ,Mathematical problem ,General Computer Science ,General Mathematics ,General Physics and Astronomy ,General Social Sciences ,General Chemistry ,resolución de problemas ,resolução de problemas ,Enseñanza del cálculo diferencial e integral en una variable ,mathematics education ,educación matemática ,General Biochemistry, Genetics and Molecular Biology ,higher mathematics ,Perspective (geometry) ,Teaching single variable differential and integral calculus ,problem solving ,Calculus ,General Earth and Planetary Sciences ,matemática superior ,Ensino do cálculo diferencial e integral em uma variável ,General Agricultural and Biological Sciences ,Curriculum ,educação matemática ,Meaning (linguistics) - Abstract
There is a wide diversity of approaches to solving problems in the teaching of mathematics. In particular, the meaning of “problem solving” differs between theory and practice. In the teaching of higher mathematics, problem solving is frequently used in single variable differential and integral calculus, as indicated by course contents and the number of university programs that include it in their curricula. We therefore investigated the ways in which mathematics teachers use problem solving in the teaching of single variable differential and integral calculus. A questionnaire was applied to teachers with experience in teaching single variable differential and integral calculus from the Universidad de Costa Rica, the Universidad Nacional de Costa Rica, the Instituto Tecnológico Costa Rica, and the Universidad Estatal a Distancia. The results reveal contradictions between teachers' conceptions of what a mathematical problem is and their implementation of problem solving in the classroom. Resumen Las líneas de investigaciones en resolución de problemas en la enseñanza de las matemáticas son muchas y con similitudes y discrepancias entre sí. En particular, lo que se entiende por resolución de problemas presenta diferencias entre la teoría y la práctica. En la enseñanza de la matemática superior, el cálculo diferencial e integral en una variable es un área rica para el uso de la resolución de problemas por sus contenidos y la cantidad de carreras universitarias que la incluyen en sus planes de estudios. Por esto se quiso indagar sobre el uso que le dan docentes de matemática a la resolución de problemas en la enseñanza del cálculo diferencial e integral en una variable. Para esto se aplicó un cuestionario a docentes con experiencia en la enseñanza del cálculo diferencial e integral en una variable de la Universidad de Costa Rica, la Universidad Nacional, el Instituto Tecnológico de Costa Rica y la Universidad Estatal a Distancia. Los resultados revelan contradicciones entre las concepciones de docentes sobre lo que es un problema matemático y su implementación en el aula. Resumo As linhas de pesquisa na resolução de problemas no ensino da matemática são muitas e com semelhanças e discrepâncias entre si. Particularmente, o que se entende por resolução de problemas apresenta diferenças entre a teoria e a prática. No ensino da matemática superior, o cálculo diferencial e integral em uma variável é uma área rica para o uso da resolução de problemas por seus conteúdos e pela quantidade de carreiras universitárias que a incluem em seus planos de estudos. Por isso, quis-se indagar sobre o uso que os docentes de matemática dão à resolução de problemas no ensino do cálculo diferencial e integral em uma variável. Para isso, foi realizado um questionário com os docentes experientes no ensino do cálculo diferencial e integral em uma variável da Universidade da Costa Rica, da Universidade Nacional, do Instituto Tecnológico da Costa Rica e da Universidade Estatal a Distância. Os resultados revelam contradições entre os conceitos dos docentes sobre o que é um problema matemático e sua implementação na sala de aula.
- Published
- 2018
37. Usefulness and Pitfalls in Sodium Intake Estimation: Comparison of Dietary Assessment and Urinary Excretion in Chilean Children and Adults
- Author
-
Marlene Aglony, Carolina Loureiro, Carolina Valdivia, Ricardo Uauy, Carmen Campino, Caroline Hill, Rodrigo Bancalari, Carolina Mendoza, Cristobal A. Fuentes, Hernán García, Cristian A. Carvajal, Carlos E. Fardella, Alejandra Tapia-Castillo, Carlos F. Lagos, Andrea Vecchiola, Rene Baudrand, Clarita Ferrada, Francisca Grob, Carmen A. Carrasco, and Alejandro Martinez-Aguayo
- Subjects
Adult ,Male ,medicine.medical_specialty ,Adolescent ,Cross-sectional study ,Urinary system ,Sodium ,Physiology ,chemistry.chemical_element ,Urine ,030204 cardiovascular system & hematology ,Overweight ,Diet Surveys ,Excretion ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Internal Medicine ,medicine ,Humans ,030212 general & internal medicine ,Chile ,Young adult ,Child ,Aged ,business.industry ,Body Weight ,Sodium, Dietary ,Middle Aged ,Cross-Sectional Studies ,Nutrition Assessment ,Endocrinology ,Blood pressure ,chemistry ,Female ,medicine.symptom ,business - Abstract
BACKGROUND High sodium intake has been associated with various noncommunicable disease like hypertension, cardiovascular disease, or stroke. To estimate accurately sodium intake is challenging in clinical practice. We investigate the usefulness and limitations of assessing sodium intake simultaneously by dietary assessment and urinary samples in both children and adults. METHODS We used a cross-sectional study design inviting 298 Chilean subjects (74 children and 222 adults) aged between 9 and 66 years of both genders. Sodium intake by dietary assessment was obtained from Chilean food composition data, based on FAO tables. Sodium and creatinine excretion were measured in 24-hour urine samples, in all participants. RESULTS Adequate urinary collection was obtained in 81% of children (59/74) and 61% of adults (135/222). The mean sodium intake by dietary assessment was similar to the sodium excretion in 24 hours (3,121±1,153mg/d vs. 3,114±1,353mg/24h, P = nonsignificant) in children but was significantly lower (3,208±1,284mg/d vs. 4,160±1,651mg/24h, P < 0.001) in adults. In both children and adults, sodium intake correlated with urinary sodium excretion (r = 0.456, P < 0.003 and r = 0.390, P < 0.001, respectively). Secondary analyses also suggested that the dietary assessment was more inaccurate in overweight adult subjects. CONCLUSIONS Our results showed that average sodium intake was higher than recommended in both children and adults (WHO ≤2,000mg/d). The sodium intake estimated by dietary assessment correlated with urinary excretion in all subjects, but in obese adults was more inaccurate than in children. Future studies to validate the appropriate test to assess sodium intake by age and nutritional status are warranted.
- Published
- 2016
38. Clinical, Biochemical, and Genetic Characteristics of 'Nonclassic' Apparent Mineralocorticoid Excess Syndrome
- Author
-
Carolina Valdivia, Sandra Solari, Andrea Vecchiola, Alejandro Martinez-Aguayo, Rene Baudrand, Hernán García, Anand Vaidya, Alejandra Tapia-Castillo, Carlos F. Lagos, Carmen Campino, Carlos E. Fardella, Fidel Allende, Cristian A. Carvajal, and Cristobal A. Fuentes
- Subjects
Adult ,Male ,medicine.medical_specialty ,Adolescent ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,Secondary hypertension ,030209 endocrinology & metabolism ,030204 cardiovascular system & hematology ,Biochemistry ,Plasma renin activity ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Endocrinology ,Mineralocorticoid receptor ,Internal medicine ,11-beta-Hydroxysteroid Dehydrogenase Type 2 ,medicine ,Humans ,Chile ,business.industry ,Mineralocorticoid Excess Syndrome, Apparent ,Biochemistry (medical) ,Middle Aged ,medicine.disease ,Hypokalemia ,Cortisone ,Blood pressure ,Cross-Sectional Studies ,Phenotype ,Apparent mineralocorticoid excess syndrome ,Microalbuminuria ,Female ,medicine.symptom ,business ,Biomarkers ,medicine.drug - Abstract
Context Classical apparent mineralocorticoid excess (AME) is a rare recessive disorder, caused by severe 11β-hydroxysteroid dehydrogenase type 2 enzyme (11β-HSD2) deficiency. AME manifests as low-renin pediatric hypertension, hypokalemia and high cortisol/cortisone (F/E) ratio. Objective To evaluate nonclassic AME (NC-AME) due to partial 11β-HSD2 insufficiency and its association with hypertension, mineralocorticoid receptor (MR) activation, and inflammatory parameters. Design Cross-sectional study. Setting Primary care cohort. Participants We recruited 127 adolescents and adults. Subjects with secondary hypertension were excluded. We measured clinical, biochemical, renal, vascular, and inflammatory variables. Sequencing of HSD11B2 gene was performed in all subjects. Main Outcome Measure NC-AME. Results Serum F/E ratio was positively associated with systolic blood pressure (BP), microalbuminuria, and high-sensitivity C-reactive protein (hs-CRP). Serum cortisone correlated with MR activation parameters even when adjusted for age, body mass index, and sex: lower cortisone with higher potassium excretion (partial r = -0.29, P = 0.002) and with lower plasma renin activity (PRA) (partial r = 0.29, P = 0.001). Consistently, we identified 9 in 127 subjects (7.1%) with high F/E ratios (first quartile) and low cortisone (last quartile), suggestive of NC-AME. These subjects had higher systolic BP, 141.4 ± 25.7 mm Hg vs 127.3 ± 18.1 mm Hg, P = 0.03; lower PRA, 0.36 ± 0.19 ng/L*s vs 0.64 ± 0.47 ng/L*s, P < 0.0001; and greater potassium excretion, microalbuminuria, hs-CRP, and plasminogen activator inhibitor. We only found in 2 out of 9 subjects with NC-AME heterozygous mutations in the HSD11B2 gene. Conclusions These findings suggest a spectrum of partial 11β-HSD2 insufficiency in a primary care cohort without the classic phenotype and genotype of AME. NC-AME may represent a phenotype of MR activation and cardiovascular risk, suggesting that these subjects could be treated with MR antagonists.
- Published
- 2018
39. Sodium Intake Is associated With Endothelial Damage Biomarkers and Metabolic Dysregulation
- Author
-
Doris Muñoz, Andrea Vecchiola, Cristobal A. Fuentes, Alejandro Martinez-Aguayo, Alejandra Tapia-Castillo, Sandra Solari, Lorena García, María Paulina Rojas, Cristian A. Carvajal, Rene Baudrand, Fidel Allende, Carmen Campino, Carolina A Valdivia, Carlos F. Lagos, Carlos E. Fardella, and Hernán García
- Subjects
Adult ,Blood Glucose ,medicine.medical_specialty ,Adolescent ,Urinary system ,Sodium ,chemistry.chemical_element ,Blood Pressure ,030204 cardiovascular system & hematology ,Recommended Dietary Allowances ,Plasma renin activity ,Excretion ,03 medical and health sciences ,chemistry.chemical_compound ,Young Adult ,0302 clinical medicine ,Risk Factors ,Internal medicine ,Plasminogen Activator Inhibitor 1 ,Internal Medicine ,Medicine ,Humans ,030212 general & internal medicine ,Chile ,Child ,Aged ,Creatinine ,Aldosterone ,Adiponectin ,business.industry ,Sodium, Dietary ,Middle Aged ,Lipids ,Oxidative Stress ,Renal Elimination ,Blood pressure ,Endocrinology ,Cross-Sectional Studies ,chemistry ,Cardiovascular Diseases ,Endothelium, Vascular ,Inflammation Mediators ,business ,Energy Metabolism ,Biomarkers - Abstract
BACKGROUND Mounting evidence has associated high sodium (HS) intake with hypertension, cardiovascular disease, and stroke. We investigated whether HS intake modulates the parameters of endothelial damage, inflammation, and oxidative stress. METHODS We used a cross-sectional study design including 223 Chilean subjects (6.9–65.0 years old). We measured aldosterone, renin activity, cortisol, cortisone, adiponectin, leptin, hsCRP, interleukin 6 (IL-6), tumor necrosis factor-α (TNF-α), plasminogen activator inhibitor type 1 (PAI-1), metalloproteinase (MMP)-9 and MMP-2 activity, and malondialdehyde. Sodium and creatinine were measured in 24-hour urine samples. The subjects were divided by sodium intake, high sodium (HS): ≥150 mEq/day, n = 118, and adequate sodium (AS): RESULTS We observed a positive correlation between urinary sodium excretion and blood pressure (r = 0.1669, P = 0.0124 for systolic and r = 0.2416, P = 0.0003 for diastolic), glycemia (r = 0.2660, P < 0.0001), and triglycerides (r = 0.1604, P = 0.0175) and a highly significant correlation between sodium excretion and PAI-1 (r = 0.2701, P < 0.0001). An inverse correlation was observed between urinary sodium and HDL-cholesterol (r = −0.2093, P = 0.0018) and adiponectin (r = −0.2679, P < 0.0001). In a linear regression model, urinary sodium excretion remained significantly associated with PAI-1 values even after adjusting for age, gender, and BMI. The HS group had higher blood pressure, glycemia, HOMA-IR, atherogenic index of plasma, and PAI-1 values than the group with AS intake. CONCLUSIONS HS intake is associated with endothelial damage (high PAI-1) and metabolic dysregulation. On the other hand, inflammation and oxidative stress parameters are not modified by sodium intake.
- Published
- 2018
40. Variables Sociodemográficas y Académicas Explicativas de la Deserción de Estudiantes en la Facultad de Ciencias Naturales de la Universidad de Playa Ancha (Chile)
- Author
-
Cristian M. Carvajal, Silvia J. Sarzoza, and José González
- Subjects
análisis estadístico ,desigualdad educativa ,Link function ,Desertion ,Parent education ,Predictor variables ,educación superior ,First order ,Two stages ,Education ,modelo logístico ,deserción ,Predictor variable ,Psychology ,Humanities - Abstract
espanolEste articulo presenta un analisis explicativo, tomando como efecto la desercion universitaria y como causas un conjunto de variables predictoras. El estudio se focalizo en los estudiantes de la Universidad de Playa Ancha, en Chile. El estudio propone como objetivo la identificacion de los factores que influyen de manera significativa en el proceso de desercion de los estudiantes de la Universidad de Playa Ancha y, cuantificar el efecto individual de cada predictor en la respuesta de un modelo estadistico. Basado en la dicotomia de la variable dependiente, se utilizo un modelo logistico con funcion de enlace binomial. El proceso de ajuste del modelo se desarrollo en dos etapas. Primero se estimaron los efectos individuales de cada variable predictora, seleccionando de entre ellas las significativas. En segundo lugar, se descartaron aquellas con efectos no significativos propendiendo un modelo parsimonioso. SE concluye que las variables que afectan directamente a la desercion son los predictores de primer orden, Ramos Aprobados (RA), Orden de Lista (OL), Estado Civil (EC) y Educacion del Padre (EP). EnglishThis article presents an explanatory analysis, taking as an effect the university dropout and as causes a set of predictor variables. The study focused on students of the University of Playa Ancha in Chile. The objective of the study was the identification of the factors that significantly influence the desertion process of the students of the Playa Ancha University and quantify the individual effect of each predictor. Based on the dichotomy of the dependent variable, a logistic model with a binomial link function was used. The process of adjustment of the model was developed in two stages. First, the individual effects of each predictor variable were estimated, selecting among them the significant ones. Secondly, those having non-significant effects were discarded, following a parsimonious model. It is concluded that the variables that directly affect the dropout are the predictors of first order, Approved Branches (RA), List Order (OL), Civil Status (EC) and Parent Education (EP)
- Published
- 2018
41. Testosterone inhibits Human Wild-Type and Chimeric Aldosterone Synthase Activity In-vitro
- Author
-
Cristian A. Carvajal, Vecchiola A, Cristobal A. Fuentes, Fardella Ce, Campino C, Carlos F. Lagos, and Solar I
- Subjects
chemistry.chemical_classification ,Aldosterone synthase ,medicine.medical_specialty ,Aldosterone ,biology ,Wild type ,Transfection ,In vitro ,chemistry.chemical_compound ,Enzyme ,Endocrinology ,chemistry ,Internal medicine ,biology.protein ,medicine ,Potency ,IC50 - Abstract
We have recently reported that in vitro, the wild-type (ASWT) and chimeric aldosterone synthase (ASCE) enzymes are inhibited by progesterone and estradiol had no effect. To explore the direct action of testosterone on wild-type and chimeric aldosterone synthase enzymes, we carried out an in vitro assay using HEK-293 cells transiently transfected with vectors containing the full ASWT or ASWT cDNAs. The effect of testosterone on AS enzyme activities was evaluated incubating with deoxycorticosterone (DOC) with or without increasing doses of testosterone. Aldosterone production was measured by HPLC-MS/MS. Docking of testosterone within the active sites of both enzymes was performed. In this system, testosterone inhibited ASWT, (90% inhibition at 5 μM, IC50=1.690 μM) with higher efficacy and potency than the ASCE (80% inhibition at 5 μM, IC50=3.176 μM). Our results show an inhibitory effect of testosterone on aldosteronesynthesis by ASWT or ASCE enzyme. This effect is a novel regulatory mechanism of testosterone action, which could affect the screening and diagnosis of primary aldosteronism.
- Published
- 2018
42. Serum cortisol and cortisone as potential biomarkers of partial 11 beta-hydroxysteroid dehydrogenase type 2 deficiency
- Author
-
Carlos E. Fardella, Alejandra Tapia-Castillo, Fidel Allende, Carmen Campino, Rene Baudrand, Constanza Pinochet, Andrea Vecchiola, Carlos F. Lagos, Virginia Iturrieta, Carolina Valdivia, Sandra Solari, Alejandro Martinez-Aguayo, Claudia Godoy, and Cristian A. Carvajal
- Subjects
Adult ,Male ,medicine.medical_specialty ,Heterozygote ,Fractional excretion of sodium ,Heredity ,Adolescent ,Hydrocortisone ,Urinary system ,Natriuresis ,030209 endocrinology & metabolism ,030204 cardiovascular system & hematology ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Predictive Value of Tests ,Internal medicine ,11-beta-Hydroxysteroid Dehydrogenase Type 2 ,Internal Medicine ,medicine ,Humans ,Genetic Predisposition to Disease ,Child ,Aldosterone ,business.industry ,Mineralocorticoid Excess Syndrome, Apparent ,Case-control study ,Heterozygote advantage ,Middle Aged ,medicine.disease ,Pedigree ,Cortisone ,Endocrinology ,Cross-Sectional Studies ,Phenotype ,chemistry ,Case-Control Studies ,Child, Preschool ,Mutation ,Apparent mineralocorticoid excess syndrome ,Female ,business ,Biomarkers ,medicine.drug - Abstract
BACKGROUND Pathogenic variations in HSD11B2 gene triggers the apparent mineralocorticoid excess syndrome (AME). There is scarce information regarding the phenotypes of subjects carrying heterozygous pathogenic variants in HSD11B2 gene. We investigated if serum cortisol/cortisone (F/E) ratio and cortisone are useful for identifying partial 11βHSD2 deficiency in those heterozygous subjects. METHODS We studied two patients diagnosed with AME and their families carrying either D223N or R213C mutation. We also evaluated 32 healthy control subjects (13 children and 19 adults) to obtain normal references ranges for all measured variables. Case 1: A boy carrying D223N mutation in HSD11B2 gene and Case 2: A girl carrying R213C mutation. We assessed serum F/E ratio and cortisone by HPLC-MS/MS, aldosterone, plasma-renin-activity(PRA), electrolytes, and HSD11B2 genetic analyses. RESULTS The normal values (median [interquartile range]) in children for serum F/E and cortisone (µg/dl) were 2.56 [2.21–3.69] and 2.54 [2.35–2.88], and in adults were 4.42 [3.70–4.90] and 2.23 [1.92–2.57], respectively. Case 1 showed a very high serum F/E 28.8 and low cortisone 0.46 µg/dl. His mother and sister were normotensives and heterozygous for D223N mutation with high F/E (13.2 and 6.0, respectively) and low cortisone (2.0 and 2.2, respectively). Case 2 showed a very high serum F/E 175 and suppressed cortisone 0.11 µg/dl. Her parents and sister were heterozygous for the R213C mutation with normal phenotype, but high F/E and low cortisone. Heterozygous subjects showed normal aldosterone, PRA, but lower fractional excretion of sodium and urinary Na/K ratio than controls. CONCLUSION Serum F/E ratio and cortisone allow to identify partial 11βHSD2 deficiencies, as occurs in heterozygous subjects, who would be susceptible to develop arterial hypertension.
- Published
- 2018
43. Citosine-Adenine-Repeat Microsatellite of 11β-hydroxysteroid dehydrogenase 2 Gene in Hypertensive Children
- Author
-
Marlene Aglony, Alejandra Tapia-Castillo, Andrea Vecchiola, Carolina Valdivia, Sandra Solari, Gareth I. Owen, Alexis M. Kalergis, Cristian A. Carvajal, Fidel Allende, Cristobal A. Fuentes, Alejandro Martinez-Aguayo, Rene Baudrand, Carmen Campino, Carlos F. Lagos, Carlos E. Fardella, and Hernán García
- Subjects
Male ,0301 basic medicine ,endocrine system ,medicine.medical_specialty ,Adolescent ,Genotype ,Blood Pressure ,Urine ,030204 cardiovascular system & hematology ,Biology ,Polymerase Chain Reaction ,03 medical and health sciences ,0302 clinical medicine ,11-beta-Hydroxysteroid Dehydrogenase Type 2 ,Internal medicine ,Internal Medicine ,medicine ,Humans ,Allele ,Child ,Alleles ,Morning ,Hydrocortisone ,Cross-Sectional Studies ,030104 developmental biology ,Endocrinology ,Blood pressure ,Gene Expression Regulation ,Child, Preschool ,Hypertension ,RNA ,Female ,Cortisone ,Body mass index ,hormones, hormone substitutes, and hormone antagonists ,Microsatellite Repeats ,medicine.drug - Abstract
BACKGROUND The impairment of 11β-hydroxysteroid dehydrogenase type 2 enzyme (11βHSD2) results in an inefficient conversion of cortisol to cortisone, which triggers hypertension. Cytosine-adenine repeat (CA repeat) microsatellite has been associated with low HSD11B2 gene expression. AIM To determine whether the CA-repeat length in intron 1 affect the serum cortisol to cortisone (F/E) ratio and/or blood pressure (BP) levels in pediatric subjects. SUBJECTS AND METHODS Eighty-one hypertensive (HT) and 117 normotensive (NT) subjects participated in this study. We measured BP levels, as well as the F and E and F/E ratio in morning sera and 12-hour urine samples. The length of CA repeats was determined through fragment analysis. We compared the allele distribution between the HT and NT groups, and the patients were dichotomized into groups with short alleles (S) (
- Published
- 2015
44. Urinary Exosomes and Their Cargo: Potential Biomarkers for Mineralocorticoid Arterial Hypertension?
- Author
-
Cristian A. Carvajal and Eric Barros
- Subjects
0301 basic medicine ,arterial hypertension ,medicine.medical_specialty ,medicine.drug_class ,Mini Review ,Endocrinology, Diabetes and Metabolism ,Urinary system ,exosomes ,030204 cardiovascular system & hematology ,Bioinformatics ,lcsh:Diseases of the endocrine glands. Clinical endocrinology ,03 medical and health sciences ,chemistry.chemical_compound ,Endocrinology ,0302 clinical medicine ,Primary aldosteronism ,Mineralocorticoid receptor ,Internal medicine ,medicine ,Endocrine system ,sodium channels ,lcsh:RC648-665 ,Aldosterone ,microRNA ,business.industry ,Endocrine Physiology ,medicine.disease ,water-electrolyte balance ,urine ,030104 developmental biology ,chemistry ,Mineralocorticoid ,biomarker ,business ,Hormone - Abstract
Arterial hypertension (AHT) currently affects approximately 40% of adults worldwide, and its pathological mechanisms are mainly related to renal, vascular, and endocrine systems. Steroid hormones as aldosterone and cortisol are highly relevant to human endocrine physiology, and also to endocrine hypertension. Pathophysiological conditions, such as primary aldosteronism, affect approximately 10% of patients diagnosed with AHT and are secondary to a high production of aldosterone, increasing the risk also for cardiovascular damage and heart diseases. Excess of aldosterone or cortisol increases the activity of the mineralocorticoid receptor (MR) in epithelial and non-epithelial cells. Current research in this field highlights the potential regulatory mechanisms of the MR pathway, including pre-receptor regulation of the MR (action of 11BHSD2), MR activating proteins, and the downstream genes/proteins sensitive to MR (e.g., epithelial sodium channel, NCC, NKCC2). Mineralocorticoid AHT is present in 15-20% of hypertensive subjects, but the mechanisms associated to this condition have been poorly described, due mainly to the absence of reliable biomarkers. In this way, steroids, peptides, and lately urinary exosomes are thought to be potential reporters of biological processes. This review highlight exosomes and their cargo as potential biomarkers of metabolic changes associated to mineralocorticoid AHT. Recent reports have shown the presence of RNA, microRNAs, and proteins in urinary exosomes, which could be used as biomarkers in physiological and pathophysiological conditions. However, more studies are needed in order to benefit from exosomes and the exosomal cargo as a diagnostic tool in mineralocorticoid AHT.
- Published
- 2017
45. Polarized epithelial cells release exosomes loaded with miRNAs capable of interacting with HSD11B2 and MR genes
- Author
-
Rene Baudrand, Alejandra Tapia-Castillo, Eric Barros, Jaime Lizama, Marlene Aglony, Cristian A. Carvajal, Carlos E. Fardella, Andrea Vecchiola, Carmen Campino, Alejandro Martinez-Aguayo, Carolina Valdivia, Sandra Solari, Carlos Salomon, Jose Vicente Gonzalez, Fidel Allende, David Ortiz, and Gabriela M. Repetto
- Subjects
Chemistry ,microRNA ,Gene ,Microvesicles ,Cell biology - Published
- 2017
46. Epigenetics and Arterial Hypertension
- Author
-
Oliviero Olivieri, Cristian A. Carvajal, Simonetta Friso, Francesca Pizzolo, and Carlos E. Fardella
- Subjects
0301 basic medicine ,Arterial hypertension ,030204 cardiovascular system & hematology ,Biology ,Small noncoding RNAs ,Cardiovascular diseases ,Chromatin remodeling ,DNA methylation ,Epigenetics ,Histone acetylation ,Histone methylation ,Histone modifications ,MicroRNAs ,03 medical and health sciences ,0302 clinical medicine ,Epigenetics of physical exercise ,Cancer epigenetics ,RNA-Directed DNA Methylation ,Epigenomics ,Genetics ,030104 developmental biology ,Histone methyltransferase - Abstract
Epigenetic phenomena refer to DNA methylation and hydroxymethylation, posttranslational histone modifications, and noncoding RNAs. Differently from genetic features of DNA, they are potentially reversible by environmental/nutritional factors, which make them possibly crucial in complex and multifactorial diseases such as arterial hypertension (AH). DNA methylation is, among the epigenetic marks, the most highlighted. Global methylation is lower in peripheral blood mononuclear cells DNA of hypertensive patients than normotensive subjects, and DNA hydroxymethylation are both modifiable by salt intake in a Dahl salt-sensitive rat model. The specific function of DNA methylation in regulating the expression of AH-related genes at promoter site was described for HSD11B2, NKCC1, sACE, ADD1, ESR1, AGT, and for other crucial genes in endocrine hypertension. Posttranslational histone methylation at different histone 3 lysine residues was observed to control the expression of WNK4, LSD1, HSD11B2, SCNN1A, alpha-ENaC, and NOS3 genes. Noncoding RNAs including several microRNAs are being studied for regulation of genes involved in steroidogenesis and the renin–angiotensin–aldosterone pathways. The current knowledge on the relationship between the main epigenetic marks associated to AH is an ongoing tour, aimed to identify epigenetic patterns and environmental factors that may lead toward novel implications in AH preventive and therapeutic strategies.
- Published
- 2017
47. The estimation of visceral adipose tissue with a body composition monitor predicts the metabolic syndrome
- Author
-
Cristian A. Carvajal, C. Eugenin, D. Figueroa, C. Tabilo, M. Moreno, Rene Baudrand, José Carlos de Miguel Domínguez, and M. Jimenez
- Subjects
Adult ,Male ,medicine.medical_specialty ,Waist ,Medicine (miscellaneous) ,Intra-Abdominal Fat ,Overweight ,Sensitivity and Specificity ,Body Mass Index ,Young Adult ,Waist–hip ratio ,Risk Factors ,Internal medicine ,Electric Impedance ,medicine ,Humans ,Resting energy expenditure ,Metabolic Syndrome ,Nutrition and Dietetics ,Anthropometry ,Waist-Hip Ratio ,business.industry ,nutritional and metabolic diseases ,Calorimetry, Indirect ,medicine.disease ,Endocrinology ,Adipose Tissue ,ROC Curve ,Obesity, Abdominal ,Basal metabolic rate ,Body Composition ,Cardiology ,Female ,Basal Metabolism ,Waist Circumference ,medicine.symptom ,Metabolic syndrome ,business ,Bioelectrical impedance analysis ,Body mass index - Abstract
Background Central obesity has a higher risk of the metabolic syndrome (MetS) and cardiovascular diseases. It is estimated by measuring waist circumference (WC) and waist-to-hip ratio (WHR), which are operator-dependent. The present study aimed to validate a body composition monitor (BCM) as a tool for estimating visceral adipose tissue (VAT), as well as to assess its capacity to predict the MetS and its correlation with anthropometric parameters. Methods We measured WC, WHR and body mass index (BMI) in 60 recruited subjects. BCM estimated VAT (1–30 points). Body composition and resting energy expenditure (REE) were compared with bioelectrical impedance analysis (BIA) and indirect calorimetry, respectively. VAT was estimated by BCM (range 1–30 points), We evaluated the capability of VAT, WC, BMI and WHR to predict the MetS by ATP-III criteria. Results The mean (SD) age of subjects was 36.8 (12.9) years, 80% were female, and 47% had the MetS. Body composition and REE estimated by BCM had a significant correlation with BIA (r = 0.85–0.91, P
- Published
- 2013
48. Hiperaldosteronismo primario y otras formas de hipertension arterial endocrina
- Author
-
Carlos E. Fardella, Cristian A. Carvajal, and Rene Baudrand
- Subjects
hipertensión secundaria ,Hipertensión arterial mineralocorticoidea ,lcsh:R5-920 ,lcsh:R ,lcsh:Medicine ,hiperaldosteronismo primario ,General Medicine ,cortisol ,lcsh:Medicine (General) ,11β-HSD2 ,aldosterona - Abstract
La hipertensión arterial (HTA) dependiente de mineralocorticoides representa actualmente una de las formas secundarias de hipertensión de mayor prevalencia. Entre las causas más prevalentes está el hiperaldosteronismo primario (HAP) cuya prevalencia es cercana al 10% de la población de hipertensos. El HAP se detecta principalmente por una elevación de la razón aldosterona a actividad renina plasmática (ARR), ya que la hipokalemia es infrecuente de encontrar. La fisiopatología del HAP se presenta como un desequilibrio en el control electrolítico a nivel renal, por mayor actividad del receptor mineralocorticoides (MR), lo cual aumenta el volumen intravascular y la presión arterial. Recientemente se ha demostrado también que el exceso de aldosterona afecta también el endotelio vascular, el tejido cardiaco entre otros. Este exceso puede ser por una alteración a nivel de la glándula suprarrenal (generalmente hiperplasia o adenoma) o formas genéticas (familiares). Por otra parte, alteraciones parciales o totales de la enzima 11β-Hidroxiesteroide deshidrogenasa tipo 2 (11β-HSD2) resulta en una metabolización total o parcial de cortisol, imitando los efectos de aldosterona sobre MR. La actividad de esta enzima se evalúa midiendo la razón cortisol a cortisona en suero por HPLC-MS/MS. La prevalencia de alteraciones parciales de la actividad de la enzima 11β-HSD2 en estudios de cohorte alcanza en alrededor del 15% en población hipertensa. El diagnóstico del HAP o deficiencias de 11BHSD2, permitiría un tratamiento específico del cuadro hipertensivo mediantes el uso de bloqueadores del receptor mineralocorticoideo y/o uso de corticoides de acción prolongada sin actividad mineralocorticoidea como dexametasona o betametasona.
- Published
- 2016
49. Adrenal dysregulation in children who were born extremely premature - a pilot study
- Author
-
Marlene Aglony, Carlos E. Fardella, Carmen Campino, Cristobal A. Fuentes, Andrea Vecchiola, Lorena García, Alejandra Tapia, Fidel Allende, Carolina Valdivia, Sandra Solari, Alexis M. Kalergis, Hernan Garcia, Rene Baudrand, Carlos F. Lagos, Cristian A. Carvajal, Carolina Loureiro, Alejandro Martinez-Aguayo, and Rodrigo Bancalari
- Subjects
Pediatrics ,medicine.medical_specialty ,Extremely premature ,business.industry ,medicine ,business - Published
- 2016
50. Aldosterone Production and Signaling Dysregulation in Obesity
- Author
-
Carlos E. Fardella, Rene Baudrand, Cristian A. Carvajal, Andrea Vecchiola, and Carlos F. Lagos
- Subjects
0301 basic medicine ,Aldosterone synthase ,medicine.medical_specialty ,Adipose tissue ,030204 cardiovascular system & hematology ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Mineralocorticoid receptor ,Adipocyte ,Internal medicine ,Renin–angiotensin system ,Internal Medicine ,medicine ,Adipocytes ,Animals ,Humans ,Obesity ,Aldosterone ,biology ,Adiponectin ,business.industry ,Leptin ,030104 developmental biology ,Endocrinology ,Receptors, Mineralocorticoid ,chemistry ,biology.protein ,business ,Signal Transduction - Abstract
In the past decades, we have extended the view of aldosterone effects beyond epithelial tissues. New evidence regarding the aldosterone/mineralocorticoid receptor (MR) pathway in active metabolic tissues, including adipose tissue, has confirmed its pathogenic role in systemic inflammation, endothelial dysfunction, insulin resistance, and dyslipidemia. Obesity, a current epidemic worldwide, increases aldosterone production by several adipocyte factors such as leptin but is also associated with local aldosterone production. In addition, obesity can modulate MR activation leading to signaling dysregulation and a pro-inflammatory profile of adipocytes. Current knowledge have deciphered that this phenotypical differences of obesity may be explained, at least in part, by novel non-genomic activation of MR, new inducers of aldosterone synthesis, and probably by several epigenetic modifications. In addition, with the understanding of the complex interplay of obesity, hormones, and receptors, targeted pharmacological therapy is expected and is currently under active research.
- Published
- 2016
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.