24 research outputs found
The potential of the basic research laboratory experience in medical training
La evidencia científica demuestra, de manera creciente año a año, la importancia de consolidar los conocimientos a partir de experiencias educativas significativas para los estudiantes. Este enfoque pedagógico, enfocado en el aprendizaje como construcción de significado, representa una experiencia mucho más provechosa en el proceso de aprendizaje, ya que implica un rol activo del estudiante, saliendo del espacio de confort de ser un mero receptor de conocimientos. En este sentido, la educación en medicina adopta cada vez más este pensamiento y se van modificando planes curriculares y formas de trabajo con alumnos en la búsqueda de transformar enfoques tradicionalistas de educación en formas educativas que acompañen la era actual del conocimiento, atravesada por las tecnologías y el aprendizaje ubicuo y autónomo.Scientific evidence demonstrates, year after year, the importance of consolidating knowledge through meaningful educational experiences for students. This pedagogical approach focused on learning as the construction of meaning represents a much more profitable experience in the learning process, since it implies an active role of the student, leaving the comfort zone of being a mere receiver of knowledge. In this sense, medical education is increasingly adopting this thinking and is modifying curricular plans and ways of working with students in the search for transforming traditionalist approaches to education into educational forms that accompany the current era of knowledge, crossed by technologies and ubiquitous and autonomous learning.Fil: Giraud Billoud, Maximiliano German. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Histología y Embriología D/mend Dr.m.burgos; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Fisiología; Argentina. Universidad Nacional de Villa Mercedes; Argentin
Tubulointerstitial injury and proximal tubule albumin transport in early diabetic nephropathy induced by type 1 diabetes mellitus
A decrease in the tubular expression of albumin endocytic transporters megalin and cubilin has been associated with diabetic nephropathy (DN), but there are no comprehensive studies to date relating early tubulointerstitial injury and the effect of the disease on both transporters in type 1 diabetes mellitus (T1DM). We used eight-week-old male C57BL/6 mice divided into two groups; one of them received the vehicle (control group), while the other received the vehicle + 200 mg/kg streptozotocin (T1DM). Ten weeks after the injection, we evaluated plasma insulin, enzymuria, urinary vitamin D-binding protein (VDBP), tubulointerstitial fibrosis and proximal tubule histology, markers of autophagy, and megalin and cubilin levels. We found a reduction in tubular protein reabsorption (albumin and VDBP as specific substances carried by both transporters) with increased tubulointerstitial injury, development of fibrosis, thickening of tubular basement membrane, and an increase in tubular cell metalloproteases. This was associated with a decrease in the renal expression of megalin and cubilin. We also observed an increase in the amount of cellular vesicles of the phagocytic system in the tubules, which could be linked to an alteration of normal intracellular trafficking of both receptors, thus affecting the normal function of transporters in early stages of DN. In diabetic animals, the added effects of tubulointerstitial injury, the decreases in megalin and cubilin expression, and an altered intracellular trafficking of these receptors, seriously affect protein reabsorptionFil: Giraud Billoud, Maximiliano German. Universidad del Desarrollo. Facultad de Medicina Clínica Alemana; Chile. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Ezquer, Fernando. Universidad del Desarrollo. Facultad de Medicina Clínica Alemana; ChileFil: Bahamonde, Javiera. Universidad del Desarrollo. Facultad de Medicina Clínica Alemana; ChileFil: Ezquer, Marcelo. Universidad del Desarrollo. Facultad de Medicina Clínica Alemana; Chil
Mesenchymal Stem Cell Therapy in Type 1 Diabetes Mellitus and Its Main Complications: From Experimental Findings to Clinical Practice
Type 1 diabetes mellitus (T1DM) is a complex multifactorial disorder which involves a loss of self-tolerance leading to the autoimmune destruction of pancreatic β−cells. Exogenous insulin administration cannot mimic precise pancreatic β-cell regulation of glucose homeostasis, thereby leading to severe long-term complications. Pancreas or islet transplant only provides partial exogenous insulin independence and induces several adverse effects, including increased morbidity and mortality. The scientific community and diabetic patients are thus, still waiting for an effective therapy which could preserve the remaining β-cells, replenish islet mass and protect newly-generated β-cells from autoimmune destruction. Mesenchymal stem cells (MSCs) have been envisioned as a promising tool for T1DM treatment over the past few years, since they could differentiate into glucose-responsive insulin-producing cells. Their immunomodulatory and proangiogenic roles can be used to help arrest β-cell destruction, preserve residual β-cell mass, facilitate endogenous β-cell regeneration and prevent disease recurrence, thereby making them ideal candidates for the comprehensive treatment of diabetic patients. This review focuses on recent pre-clinical data supporting MSC use in regenerating β-cell mass and also in treating several T1DM-associated complications. Clinical trial results and the ongoing obstacles which must be addressed regarding the widespread use of such therapy are also discussed.Fil: Ezquer, Marcelo. Universidad del Desarrollo. Facultad de Medicina Clínica Alemana; ChileFil: Arango Rodriguez, Martha. Universidad del Desarrollo. Facultad de Medicina Clínica Alemana; ChileFil: Giraud Billoud, Maximiliano German. Universidad del Desarrollo. Facultad de Medicina Clínica Alemana; Chile. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Ezquer, Fernando. Universidad del Desarrollo. Facultad de Medicina Clínica Alemana; Chil
Diabetic nephropathy, autophagy and proximal tubule protein endocytic transport: A potentially harmful relationship
Diabetic nephropathy (DN) is the most frequent cause of chronic renal failure. Until now, the pathophysiological mechanisms that determine its development and progression have not yet been elucidated. In the present study, we evaluate the role of autophagy at early stages of DN, induced in type 2 diabetes mellitus (T2DM) mouse, and its association with proximal tubule membrane endocytic receptors, megalin and cubilin. In T2DM animals we observed a tubule-interstitial injury with significantly increased levels of urinary GGT and ALP, but an absence of tubulointerstitial fibrosis. Kidney proximal tubule cells of T2DM animals showed autophagic vesicles larger than those observed in the control group, and an increase in the number of these vesicles marked with LBPA by immunofluorescence. Furthermore, a significant decrease in the ratio of LC3II/LC3I isoforms and in p62 protein expression in DN affected animals is shown. Finally, we observed a marked increase in urinary albumin and vitamin D binding-protein levels in T2DM animals as well as a significant decrease in expression of megalin in the renal cortex. These results indicate an alteration of the tubular endocytic transporters in DN, which could be related to autophagic dysfunction, which would in turn result in impaired organelle recycling, thus contributing to the progression of this disease.Fil: Giraud Billoud, Maximiliano German. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Fader Kaiser, Claudio Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Agüero, Rocio. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas; ArgentinaFil: Ezquer, Fernando. Universidad del Desarrollo; ChileFil: Ezquer, Marcelo. Universidad del Desarrollo; Chil
Evaluation of female masculinization in Pomacea canaliculata (Caenogastropoda, Ampullariidae) induced by tributyltin, heavy metals, and uranium in culture water
All female Pomacea canaliculata develop a small, male-like copulatory apparatus a few days after birth, which growths slowly until sexual maturity, and even further in older age. Previous studies have found trace elements like mercury (Hg), arsenic (As) and uranium (U) in tap water used for snail culture, and that these elements were accumulated in snail tissues. Here, we test whether the presence of these metals at maximum allowed concentrations (Environmental Protection Agency-EPA) in aquarium water could affect the development of the copulatory apparatus in mature females. Females of different ages were used as controls, grown in reconstituted metal-free water with or without the addition of Hg, As and U, as well as tributyltin (TBT), a compound used as masculinizing agent. Six and seven months old females cultured in tap water showed a longer penis and penile sheath, and a greater overall development of the copulatory apparatus, measured by an index (DI), as compared with same-age females cultured in reconstituted water. Moreover, when females were exposed to Hg, As or U at the maximum contaminant levels for human consumption allowed by EPA regulations, there was no further development of the copulatory apparatus, while there was a clearly positive effect in TBT-exposed females. This study confirms the masculinizing effect of organotin compounds on female copulatory apparatus and discusses the usefulness of the development of these organs as a bioindicator of environmental pollution.Fil: Giraud Billoud, Maximiliano German. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Fisiología; Argentina. Universidad Nacional de Villa Mercedes; ArgentinaFil: Campoy Díaz, Alejandra Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Fisiología; Argentina. Universidad Nacional de Villa Mercedes; ArgentinaFil: Mansilla, Emilio. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias; ArgentinaFil: Vega, Israel Aníbal. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Fisiología; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales. Departamento de Biología; Argentin
Monitoring of SARS-CoV-2 RNA in wastewater as an epidemiological surveillance tool in Mendoza, Argentina
Wastewater-based epidemiology (WBE) is an emerging tool that gives temporal and spatial information on a population's health status. Here, we report the epidemiological dynamics of a population of ~1.2 million residents in the metropolitan region of Mendoza province, Argentina, within the period July 2020 to January 2021. We combined the use of WBE of two wastewater treatment plants with epidemiological surveillance of the corresponding populations. We applied two viral concentration methods (polyethylene glycol precipitation and aluminum-based adsorption-flocculation) and RNA isolation methods in each wastewater sample to increase the possibility of detection and quantification of nucleocapsid markers (N1 and N2) of SARS-CoV-2 by RT-qPCR. Overall, our results allowed us to trace the rise, exponential growth, plateau, and fall of SARS-CoV-2 infections for 26 weeks. Individual analysis for each wastewater treatment plant showed a positive correlation between the viral load of SARS-CoV-2 genetic markers and COVID-19 cases that were diagnosed per week. Our findings indicate that WBE is a useful epidemiological indicator to anticipate the increase in COVID-19 cases and monitor the advance of the pandemic and different waves of infections.Fil: Giraud Billoud, Maximiliano German. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Cuervo, María Paula. Universidad Nacional de Cuyo; ArgentinaFil: Altamirano, Jorgelina Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; ArgentinaFil: Pizarro, Marcela. Universidad Nacional de Cuyo; ArgentinaFil: Aranibar, Julieta Nelida. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; ArgentinaFil: Catapano, Adolfo. Agua y Saneamientos de Mendoza; ArgentinaFil: Cuello, Héctor. Gobierno de la Provincia de Mendoza. Hospital Central de Mendoza.; ArgentinaFil: Masachessi, Gisela. Universidad Nacional de Córdoba. Facultad de Medicina. Instituto de Virología Dr. J. M. Vanella; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Vega, Israel Aníbal. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; Argentin
Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector
A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements
Aging and retinoid X receptor agonists on masculinization of female Pomacea canaliculata, with a critical appraisal of imposex evaluation in the Ampullariidae
Ampullariidae are unique among gastropods in that females normally show a primordium of the copulatory apparatus (CApp). The aims of this study were (a) to quantitatively evaluate the development and growth of the female CApp with age; (b) to compare the effects of RXR and PPARγ agonists in adult females of known age and (c) to explore the effect of masculinizing RXR agonists on the expression of RXR in the CApp. It was found that the CApp grows and develops with age. A significant increase in penile sheath length (PsL) and also in a developmental index (DI) was observed in 7–8 months old females, as compared with 4–5 months old ones. A reported endogenous agonist of RXR, 9-cis retinoic acid (9cis-RA), as well as two organotin compounds, tributyltin (TBT) and triphenyltin (TPT) which have been also reported to bind to RXR, were injected and its masculinizing effects were measured. Also, the effect of a PPARγ agonist, rosiglitazone, was studied. All studied RXR agonists, but not the PPARγ agonist, were effective in increasing PsL, penile length (PL) and DI. Finally, the expression of the RXR in the CApp was studied (Western blot) in control, TBT, TPT, and 9cis-RA treated females. A significantly increased expression of RXR was only observed after 9cis-RA treatment. It is concluded that (a) development and growth of the CApp is significantly affected by female age; (b) reported RXR agonists, but not a PPARγ agonist, cause female masculinization of young females. An appraisal of previous studies of female masculinization in the Ampullariidae has also been made and it is emphasized that the masculinizing effect of aging should be considered, particularly when interpreting field data.Fil: Giraud Billoud, Maximiliano German. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Medicas. Instituto de Fisiologia; ArgentinaFil: Castro Vazquez, Alfredo Juan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Medicas. Instituto de Fisiologia; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; Argentin
Short-Term Estivation and Hibernation Induce Changes in the Blood and Circulating Hemocytes of the Apple Snail Pomacea canaliculata
States of natural dormancy include estivation and hibernation. Ampullariids are exemplarybecause they undergo estivation when deprived of water or hibernation when exposed to very lowtemperatures. Regardless of the condition, ampullariids show increased endogenous antioxidantdefenses, anticipating the expected respiratory burst during reoxygenation after reactivation, knownas ?Preparation for Oxidative Stress (POS)?. In this work, we tested the POS hypothesis for changesin the blood and hemocytes of the bimodal breather Pomacea canaliculata (Ampullariidae) induced atexperimental estivation and hibernation. We described respiratory (hemocyanin, proteins, lactate),antioxidant (GSH, uric acid, SOD, CAT, GST), and immunological (hemocyte levels, ROS production)parameters. We showed that, although the protein level remains unchanged in all experimentalgroups, hemocyanin increases in response to estivation. Furthermore, lactate remains unchangedin challenged snails, suggesting an aerobic metabolism during short-term challenges. Blood uricacid increases during estivation and arousal from estivation or hibernation, supporting the previouslyproposed antioxidant role. Regarding hemocytes, we showed that the total populationincreases with all challenges, and granulocytes increase during hibernation. We further showed thathibernation affects ROS production by hemocytes, possibly through mitochondrial inhibition. Thisstudy contributed to the knowledge of the adaptive strategies of ampullariids to tolerate adverseenvironmental conditions.Fil: Rodríguez, Cristian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Campoy Díaz, Alejandra Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales. Departamento de Biología; ArgentinaFil: Giraud Billoud, Maximiliano German. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; Argentin
Functional anatomy of male copulatory organs of Pomacea canaliculata (Caenogastropoda Ampullariidae)
This study was aimed to investigate the functional morphology of copulation and sperm transfer in the invasive snail Pomacea canaliculata. Three-dimensional renderings of the male copulatory apparatus were made and showed elaborate systems for innervation and for hemolymph supply and drainage. A key component of the male copulatory apparatus is the penial sheath, which shows three specialized glands; the medial and distal glands may participate in adherence to the mantle cavity wall of the female during copulation. The outer gland has an epithelium composed of columnar cells with branched microvilli, mucous goblet cells and large granular secretory cells containing intragranular crystalloids, which produce an exocrine secretion during copulation. The interaction of male/female copulatory organs was studied in dissections of snap-frozen pairs. Sperm are left in the sperm pit, at the end of the pallial spermiduct. Afterwards, the muscular action of the penial bulb takes the sperm up to the vermiform penis, which slides from the penial pouch into the central groove of the penial sheath, and it later emerges through a T-shaped sulcus of this structure and enters the female vagina. Then, it climbs through the capsule duct, and its tip reaches the proximity of the seminal receptacle. A model of copulation and sperm transfer is presented on the basis of the new findings and on published literature.Fil: Giraud Billoud, Maximiliano German. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto Histologia y Embriología de Mendoza "Dr. M. Burgos"; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas; ArgentinaFil: Gamarra Luques, Carlos Diego. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto Histologia y Embriología de Mendoza "Dr. M. Burgos"; ArgentinaFil: Castro Vazquez, Alfredo Juan. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto Histologia y Embriología de Mendoza "Dr. M. Burgos"; Argentin