Melioidosis en Colombia, descripción de un caso clínico y consideraciones epidemiológicas

Melioidosis is an infectious disease caused by Burkholderia pseudomallei whose clinical diagnosis can be difficult due not only to its varied clinical presentation but also to the difficulties in the microbiological diagnosis.Thus, it may be necessary to use molecular techniques for its proper identification once it is suspected.There are few antibiotics available for the treatment of this disease, which must be used over a long period of time. Although it is known to be endemic in Thailand, Malaysia, Singapore, Vietnam, and Australia, in Colombia there are few reported cases.We describe a case of melioidosis in the northern region of Colombia. Additionally, we review its clinical characteristics and treatment and we describe the local epidemiology of this disease.La melioidosis es una enfermedad infecciosa causada por Burkholderia pseudomallei cuyo diagnóstico clínico puede ser difícil debido a su variada presentación clínica y a las dificultades del diagnóstico microbiológico, por lo cual pueden requerirse técnicas moleculares para su adecuada identificación una vez se sospecha su presencia.Son pocos los antibióticos disponibles para el tratamiento de esta enfermedad y, además, deben usarse durante un tiempo prolongado. Aunque se conoce por ser endémica en Tailandia, Malasia, Singapur, Vietnam y Australia, en Colombia se han reportado algunos pocos casos.Se presenta un caso de melioidosis en la región norte de Colombia, se hace una revisión de las características clínicas y el tratamiento, y se describe la epidemiología local de esta enfermedad

Folistatina, resistencia a la insulina y composición corporal en adultos colombianos

Introducción: La folistatina es una proteína capaz de neutralizar varias hormonas de la familia del TGF-?, tales como la activina, las proteínas morfogénicas del hueso y la miostatina. Al inactivar la activina y la folistatina reduce la secreción de FSH. La folistatina se produce además de en el ovario en muchos otros tejidos, por ello se sospecha que tiene otros efectos. En ratones, la deleción genética de la folistatina se acompaña de resistencia a la insulina (RI). Sin embargo, la asociación entre la folistatina plasmática y RI medida directamente no ha sido evaluada en humanos. Métodos: En 81 participantes entre 30 y 69 años (56% mujeres, 54% con sobrepeso, 13% con obesidad), determinamos antropometría, composición corporal, factores de riesgo cardiovascular y múltiples índices de RI: Área incremental bajo la curva de insulina, índice de sensibilidad a la insulina según Gutt, Homeostatic Model Assessment – Insulin Resistance (HOMA-IR) e insulinemia en ayuno. Un subgrupo de 21 participantes se sometió además a un clamp hiperinsulinémico-euglucémico. La folistatina y la miostatina se midieron en plasma de ayuno, empleando técnicas inmunométricas. Resultados: La concentración promedio de folistatina fue 2.517±830 pg/mL, sin diferencia entre sexos (p=0,55). La folistatina tuvo una tendencia a correlación positiva con el porcentaje de masa magra (r=0,19, p=0,088) y negativa con el porcentaje de grasa corporal (r= -0,19, p=0,097). La folistatina no se correlacionó con índices de RI derivados de la PTOG pero sí con la captación corporal de glucosa en el clamp (r=0,42, p=0,031). No se halló asociación entre las concentraciones de folistatina y miostatina plasmáticas. Conclusión: Los niveles de folistatina mostraron una tendencia hacia una correlación positiva con la masa muscular y negativa con adiposidad corporal. Esto concuerda con el efecto inhibitorio de la folistatina sobre la miostatina. Aunque la folistatina no correlacionó con índices indirectos de RI, sí lo hizo con la determinación directa de sensibilidad a la insulina en el clamp hiperinsulinémico-euglucémico

Overview of recent TJ-II stellarator results

The main results obtained in the TJ-II stellarator in the last two years are reported. The most important topics investigated have been modelling and validation of impurity transport, validation of gyrokinetic simulations, turbulence characterisation, effect of magnetic configuration on transport, fuelling with pellet injection, fast particles and liquid metal plasma facing components. As regards impurity transport research, a number of working lines exploring several recently discovered effects have been developed: the effect of tangential drifts on stellarator neoclassical transport, the impurity flux driven by electric fields tangent to magnetic surfaces and attempts of experimental validation with Doppler reflectometry of the variation of the radial electric field on the flux surface. Concerning gyrokinetic simulations, two validation activities have been performed, the comparison with measurements of zonal flow relaxation in pellet-induced fast transients and the comparison with experimental poloidal variation of fluctuations amplitude. The impact of radial electric fields on turbulence spreading in the edge and scrape-off layer has been also experimentally characterized using a 2D Langmuir probe array. Another remarkable piece of work has been the investigation of the radial propagation of small temperature perturbations using transfer entropy. Research on the physics and modelling of plasma core fuelling with pellet and tracer-encapsulated solid-pellet injection has produced also relevant results. Neutral beam injection driven Alfvénic activity and its possible control by electron cyclotron current drive has been examined as well in TJ-II. Finally, recent results on alternative plasma facing components based on liquid metals are also presented. ISSN:0029-5515 ISSN:1741-432

Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

Plasma Levels of Myonectin But Not Myostatin or Fibroblast-Derived Growth Factor 21 Are Associated with Insulin Resistance in Adult Humans without Diabetes Mellitus

BackgroundMyokines are a group of protein mediators produced by skeletal muscle under stress or physical exertion. Even though their discovery and effects in cell culture and animal models of disease have elicited great enthusiasm, very little is known about their role in human metabolism. We assessed whether plasma concentrations of three known myokines [myonectin, myostatin, and fibroblast-derived growth factor 21 (FGF-21)] would be associated with direct and indirect indicators of insulin resistance (IR) in individuals who did not have a diagnosis of diabetes.MethodsWe studied 81 adults of both sexes comprising a wide range of body adiposity and insulin sensitivity. All participants underwent a thorough clinical assessment and a 5-point oral glucose tolerance test with calculation of multiple IR and insulin sensitivity indices. Twenty-one of them additionally underwent a hyperinsulinemic–euglycemic clamp with determination of steady-state whole-body insulin-stimulated glucose disposal (“M”). We compared plasma myokine concentrations across quartiles of IR indices and clinical IR surrogates, and explored the correlation of each myokine with the M-value.ResultsPlasma myonectin levels increased monotonically across quartiles of the incremental area under the insulin curve (higher values indicate more IR) (p-trend = 0.021) and decreased monotonically across quartiles of the insulin sensitivity index (ISI – higher values indicate less IR) (p-trend = 0.012). After multivariate adjustment for other relevant determinants of IR (body mass index, age, and sex), the negative association of myonectin with ISI persisted (standardized beta = −0.235, p = 0.023). Myostatin was not associated with any clinical IR indicator or direct IR index measure. In multivariate analyses, FGF-21 showed a trend toward a positive correlation with glucose disposal that did not reach statistical significance (standardized beta = 0.476, p = 0.091).ConclusionThe secretion of myonectin may constitute an attempt at a compensatory mechanism against IR in humans

Biodiversidad 2015. Estado y tendencias de la biodiversidad continental de Colombia

El propósito de este documento es fortalecer la capacidad de agentes públicos y privados para la aplicación de la PNGIBSE, que constituye en sí misma una apuesta de interfaz entre ciencia, política y sociedad en la perspectiva de construir sostenibilidad en el desarrollo. Además de ello, representa un insumo para el seguimiento a los compromisos del país frente a convenios e iniciativas internacionales (CDB, IPBES, OCDE), así como un mecanismo pedagógico para generar interés, conciencia y apropiación de las diferentes dimensiones de la biodiversidad del país.Bogotá, D. C., ColombiaInstituto de Investigación de Recursos Biológicos Alexander von Humboldtreporte.humboldt.org.coreporte.humboldt.org.co/biodiversidad/en