https://repositorio.uca.edu.ar/handle/123456789/700 2026-04-08T00:09:12Z https://repositorio.uca.edu.ar/handle/123456789/18359 Título: La Antártida como modelo de desincronización biológica y análogo espacial; Antarctica as a model of biological desynchronization and space analogue Autor: Vigo, Daniel Eduardo Resumen: Abstract: The extreme conditions of isolation and conϐinement that characterize the most remote Antarctic stations, in addition to the permanent absence of daylight prevailing for several months, make them an ideal model for the study of human biological desynchronization and for investigating various aspects related to human space exploration. This chapter provides a description of scientiϐic studies conducted since 2014 at the Argentine Antarctic station Belgrano II, focusing on the research of the impact of the polar night on various psychophysiological variables, as well as its use as a space analog.; Resumen Las condiciones extremas de aislamiento y conϐinamiento que caracterizan a las estaciones antárticas más aisladas, junto con la ausencia de luz natural que prevalece durante varios meses, las convierten en un modelo ideal para el estudio de fenómenos de desincronización biológica en humanos y para investigar diversos aspectos relacionadas con la exploración humana del espacio. Este capítulo presenta una descripción de los estudios cientíϐicos llevados a cabo desde 2014 en la base antártica argentina Belgrano II, centrándose en la investigación del impacto de la noche polar en diversas variables psicoϐisiológicas, así como en su 2024-01-01T00:00:00Z https://repositorio.uca.edu.ar/handle/123456789/16519 Título: The epidemiology and etiopathogenesis of graves’ disease Autor: Saban, Melina; Curriá, Marina Inés; Romeo, Horacio; Barreiro Arcos, María Laura Resumen: Abstract: Graves' disease (GD) is the most common cause of hyperthyroidism. GD is an endocrine autoimmune disorder caused by the presence in serum of TSH receptor-stimulating autoantibodies (TRAb) that induce the overproduction of 3,3',5'-triiodo-L-thyronine (T3) and L-thyroxine (T4) and enlargement of the thyroid gland. GD is also often accompanied by autoantibodies against other thyroid antigens such as thyroglobulin and thyroid peroxidase. The prevalence of GD is around 1-1.5 % worldwide, with an incidence of 20 to 50 new cases per 100,000 inhabitants per year with a considerably higher frequency in women than in men. In addition to hyperthyroidism, extrathyroidal manifestations including orbitopathy, thyroid dermopathy, and acropachy are frequently associated with GD. Genetic factors (such as HLA-DR3, CD40, CTLA-4, PTPN22, FOXP3, and CD25) and environmental and endogenous factors (such as age, emotional stress, smoking, female sex, pregnancy, bacterial and viral infections, and some drugs) contribute to the development of GD. Although the pathogenesis of GD has been better understood, directed treatments against the molecular mechanisms are lacking. Therapies for GD are presently based upon antithyroid drugs, but due to the high rate of recurrence in hyperthyroidism, ablation of the thyroid by either radioiodine treatment or surgical thyroidectomy is the only treatment available. In the present chapter, we provide updated knowledge on the epidemiology and etiopathogenesis of GD. 2023-01-01T00:00:00Z https://repositorio.uca.edu.ar/handle/123456789/16511 Título: Sturzrisiko, zirkadiane Rhythmen, Vagusaktivität und Melatonin Autor: Goswami, Nandu; Brix, Bianca; Abulafia, Carolina Andrea; Vigo, Daniel Eduardo; Cornelissen, Germaine; Cardinali, Daniel Pedro; Moser, Maximilian Resumen: Zusammenfassung: Altern ist mit einer Verringerung der Schwingungsamplitude des Tagesverlaufs von physiologischen Variablen verbunden. Die Häufigkeit von Stürzen folgt bei älteren Menschen einem Tagesgang. Darüber hinaus sind die Zusammenhänge zwischen Alterungsprozessen und Faktoren, die vegetative Störungen begünstigen, gut bekannt. So konnte ein starker Zusammenhang zwischen Messgrößen des vegetativen Nervensystems und Alterung gezeigt werden. Insbesondere die Vagusaktivität nimmt ab dem 20. Lebensjahr ab. Die Aktivität des autonomen Nervensystems und ihre zirkadiane Veränderung können eine wichtige Rolle für die Aufrechterhaltung der Blutdruckregulation beim Aufstehen spielen. Ein besonders markanter Tagesrhythmus wurde für Melatonin nachgewiesen, das während der Nacht den Höhepunkt seiner Ausschüttung erreicht. Die zirkadiane Tagesamplitude von Melatonin nimmt mit dem Alter ab, was die Frage aufwirft, ob diese Abnahme mit einem höheren Sturzrisiko zusammenhängt. 2021-01-01T00:00:00Z https://repositorio.uca.edu.ar/handle/123456789/16499 Título: Melatonin and healthy aging Autor: Cardinali, Daniel Pedro Resumen: Abstract: Preservation of a robust circadian rhythmicity (particulsarly of the sleep/wake cycle), a proper nutrition and adequate physical exercise are key elements for healthy aging. Aging comes along with circadian alteration, e.g. a disrupted sleep and inflammation, that leads to metabolic disorders. In turn, sleep cycle disturbances cause numerous pathophysiological changes that accelerates the aging process. In the central nervous system, sleep disruption impairs several functions, among them, the clearance of waste molecules. The decrease of plasma melatonin, a molecule of unusual phylogenetic conservation present in all known aerobic organisms, plays a particular role as far as the endocrine sequels of aging. Every day, the late afternoon/nocturnal increase of melatonin synchronizes both the central circadian pacemaker located in the hypothalamic suprachiasmatic nuclei as well as myriads of peripheral cellular circadian clocks. This is called the “chronobiotic effect” of melatonin, the methoxyindole being the prototype of the endogenous family of chronobiotic agents. In addition, melatonin exerts a significant cytoprotective action by buffering free radicals and reversing inflammation via down regulation of proinflammatory cytokines, suppression of low degree inflammation and prevention of insulin resistance. Because of these properties melatonin has been advocated to be a potential therapeutic tool in COVID 19 pandemic. Melatonin administration to aged animals counteracts a significant number of senescence-related changes. In humans, melatonin is effective both as a chronobiotic and a cytoprotective agent to maintain a healthy aging. Circulating melatonin levels are consistently reduced in the metabolic syndrome, ischemic and non-ischemic cardiovascular diseases and neurodegenerative disorders like the Alzheimer's and Parkinson's diseases. The potential therapeutic value of melatonin has been suggested by a limited number of clinical trials generally employing melatonin in the 2–10 mg/day range. However, from animal studies the cytoprotective effects of melatonin need higher doses to become apparent (i.e. in the 100 mg/day range). Hence, controlled studies employing melatonin doses in this range are urgently needed. 2021-01-01T00:00:00Z