1,393 research outputs found

    Human placenta-derived mesenchymal stem cells stimulate neuronal regeneration by promoting axon growth and restoring neuronal activity

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    In the last decades, mesenchymal stem cells (MSCs) have become the cornerstone of cellular therapy due to their unique characteristics. Specifically human placenta-derived mesenchymal stem cells (hPMSCs) are highlighted for their unique features, including ease to isolate, non-invasive techniques for large scale cell production, significant immunomodulatory capacity, and a high ability to migrate to injuries. Researchers are exploring innovative techniques to overcome the low regenerative capacity of Central Nervous System (CNS) neurons, with one promising avenue being the development of tailored mesenchymal stem cell therapies capable of promoting neural repair and recovery. In this context, we have evaluated hPMSCs as candidates for CNS lesion regeneration using a skillful co-culture model system. Indeed, we have demonstrated the hPMSCs ability to stimulate damaged rat-retina neurons regeneration by promoting axon growth and restoring neuronal activity both under normoxia and hypoxia conditions. With our model we have obtained neuronal regeneration values of 10%–14% and axonal length per neuron rates of 19-26, μm/neuron. To assess whether the regenerative capabilities of hPMSCs are contact-dependent effects or it is mediated through paracrine mechanisms, we carried out transwell co-culture and conditioned medium experiments confirming the role of secreted factors in axonal regeneration. It was found that hPMSCs produce brain derived, neurotrophic factor (BDNF), nerve-growth factor (NGF) and Neurotrophin-3 (NT-3), involved in the process of neuronal regeneration and restoration of the physiological activity of neurons. In effect, we confirmed the success of our treatment using the patch clamp technique to study ionic currents in individual isolated living cells demonstrating that in our model the regenerated neurons are electrophysiologically active, firing action potentials. The outcomes of our neuronal regeneration studies, combined with the axon-regenerating capabilities exhibited by mesenchymal stem cells derived from the placenta, present a hopeful outlook for the potential therapeutic application of hPMSCs in the treatment of neurological disorders.post-print2885 K

    Arqueometria antropológica en el sepulcro megalítico de El Palomar: contribución al conocimiento histórico de la campiña sevillana

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    Presentamos un estudio de la analítica realizada en huesos humanos encontrados en el interior de la estructura dolménica de El Palomar que ha sido realizada en la Universidad Autónoma de Barcelona. Este trabajo se integra en el Proyecto de Investigación que sobre Análisis del Proceso Cultural Operado en las Sociedades Agrarias de la Campiña Sevillana se está llevando a cabo en el Departamento de Prehistoria y Arqueología de la Universidad de Sevilla

    New variants of SARS-CoV-2

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    The emergence and spread of new variants of SARS-CoV-2 has produced enormous interest due to their possible implication in the improved transmissibility of the virus, their consequences in the individual evolution of the infection, as well as in the possible escape from the immunity generated by the current vaccines. The variants that attract most attention are those of public health concern, including B.1.1.7 (UK), P.1 (Brazilian) and B.1.351 (South African). This list is extended by the variants of interest that emerge and are expanding in certain countries but are found sporadically in others, such as B.1.427 and B.1.429 (Californians) or B.1.617 (Indian). Whole genome sequencing or strategies specifically targeting the spicule gene are used in the microbiology laboratories for characterization and detection. The number of infected individuals, the sanitary situation of each country, epidemiological measures and vaccination strategies influence its dispersion and new variants are expected to emerge. This emergence can only be avoided today by increasing the vaccinated population in all countries and by not relaxing epidemiological containment measures. It is not excluded that in the future it will be necessary to revaccinate against new variants.post-print186 K

    COVID-19: Some unresolved issues

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    Two years after the COVID-19 pandemic, many uncertainties persist about the causal agent, the disease and its future. This document contains the reflection of the COVID-19 working group of the Official College of Physicians of Madrid (ICOMEM) in relation to some questions that remain unresolved. The document includes considerations on the origin of the virus, the current indication for diagnostic tests, the value of severity scores in the onset of the disease and the added risk posed by hypertension or dementia. We also discuss the possibility of deducing viral behavior from the examination of the structure of the complete viral genome, the future of some drug associations and the current role of therapeutic resources such as corticosteroids or extracorporeal oxygenation (ECMO). We review the scarce existing information on the reality of COVID 19 in Africa, the uncertainties about the future of the pandemic and the status of vaccines, and the data and uncertainties about the long-term pulmonary sequelae of those who suffered severe pneumonia.post-print462 K

    Expression of epicardial adipose tissue thermogenic genes in patients with reduced and preserved ejection fraction heart failure

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    [Abstract] Epicardial adipose tissue has been proposed to participate in the pathogenesis of heart failure. The aim of our study was to assess the expression of thermogenic genes (Uncoupling protein 1 (UCP1), peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α), and PR-domain-missing 16 (PRDM16) in epicardial adipose tissue in patients with heart failure, stablishing the difference according to left ventricular ejection fraction (reduced or preserved). Among the 75 patients in our study, 42.7% (n=32) had reduced left ventricular ejection fraction. UCP1, PGC1α and PRDM16 mRNA in EAT were significantly lower in patients with reduced left ventricular ejection fraction. Multiple regression analysis showed that age, male gender, body max index, presence of obesity, type-2-diabetes mellitus, hypertension and coronary artery disease and left ventricular ejection fraction were associated with the expression levels of UCP1, PGC1α and PRDM16 mRNA. Thermogenic genes expressions in epicardial adipose tissue (UCP1: OR 0.617, 95%CI 0.103-0.989, p=0.042; PGC1α: OR 0.416, 95%CI 0.171-0.912, p=0.031; PRDM16: OR 0.643, 95%CI 0.116-0.997, p=0.044) were showed as protective factors against the presence of heart failure with reduced left ventricular ejection fraction, and age (OR 1.643, 95%CI 1.001-3.143, p=0.026), presence of coronary artery disease (OR 6.743, 95%CI 1.932-15.301, p<0.001) and type-2-diabetes mellitus (OR 4.031, 95%CI 1.099-7.231, p<0.001) were associated as risk factors. The adequate expression of thermogenic genes has been shown as possible protective factors against heart failure with reduced ejection fraction, suggesting that a loss of functional epicardial adipose tissue brown-like features would participate in a deleterious manner on heart metabolism. Thermogenic genes could represent a future novel therapeutic target in heart failure.Ministerio de Salud, Servicios Sociales e Igualdad; PI13/02542Ministerio de Salud, Servicios Sociales e Igualdad; PI11/01661Red de Investigación Cardiovascular (España), RD12/0042/003

    Persistence and viability of SARS-CoV-2 in primary infection and reinfections

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    Since the beginning of the SARS-CoV-2 epidemic, virus isolation in the infected patient was only possible for a short period of time and it was striking that this occurred constantly and did not provide guidance on the clinical course. This fact led to confusion about the efficacy of some of the drugs initially used, which seemed to have a high efficiency in viral clearance and proved ineffective in modifying the course of the disease. The immune response also did not prove to be definitive in terms of evolution, although most of the patients with very mild disease had a weak or no antibody response, and the opposite was true for the most severe patients. With whatever the antibody response, few cases have been re-infected after a first infection and generally, those that have, have not reproduced a spectrum of disease similar to the first infection. Among those re-infected, a large number have been asymptomatic or with very few symptoms, others have had a moderate picture and very few have had a poor evolution. Despite this dynamic of rapid viral clearance, laboratory tests were still able to generate positive results in the recovery of genomic sequences and this occurred in patients who were already symptom-free, in others who were still ill and in those who were very seriously ill. There was also no good correlate. For this reason and with the perspective of this year and the half of pandemic, we compiled what the literature leaves us in these aspects and anticipating that, as always in biology, there are cases that jump the limits of the general behavior of the dynamics of infection in genera

    Actions and attitudes on the immunized patients against SARS-CoV-2

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    The access to COVID vaccines by millions of human beings and their high level of protection against the disease, both in its mild and severe forms, together with a plausible decrease in the transmission of the infection from vaccinated patients, has prompted a series of questions from the members of the College of Physicians of Madrid (ICOMEM) and the society. The ICOMEM Scientific Committee on this subject has tried to answer these questions after discussion and consensus among its members. The main answers can be summarized as follows: The occurrence of new SARS-CoV-2 infections in both vaccinated and previously infected patients is very low, in the observation time we already have. When breakthrough infections do occur, they are usually asymptomatic or mild and, purportedly, should have a lower capacity for transmission to other persons. Vaccinated subjects who have contact with a SARS-CoV-2 infected patient can avoid quarantine as long as they are asymptomatic, although this decision depends on variables such as age, occupation, circulating variants, degree of contact and time since vaccination. In countries with a high proportion of the population vaccinated, it is already suggested that fully vaccinated persons could avoid the use of masks and social distancing in most circumstances. Systematic use of diagnostic tests to assess the immune response or the degree of protection against reinfection after natural infection or vaccination is discouraged, since their practical consequences are not known at this time. The existing information precludes any precision regarding a possible need for future revaccination. This Committee considers that when mass vaccination of health care workers and the general population is achieved, SARS-CoV-2 screening tests could be avoided at least in out-patient care and in the case of exploratory procedures that do not require hospitalizatio

    Definición del núcleo optimizado de la colección de conservación del manzano español

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    5 Pags.- 1 Tabl.Este trabajo tiene como objetivo determinar la estrategia más adecuada para la selección del conjunto mínimo de accesiones (núcleo optimizado) que represente eficientemente la variación genética del manzano conservado en las colecciones españolas. Este núcleo optimizado mediante criterios genéticos constituirá la base de la colección nuclear de conservación, que podrá ser complementado con accesiones seleccionadas por otros criterios (morfo-fisiológicos, agronómicos, valor histórico, etc.). Se ha evaluado la eficiencia de estrategias de selección por búsqueda local estocástica avanzada (ASLS) que diferían tanto por el tamaño final del núcleo como por la combinación (y peso relativo) de las medidas de distancia genética y riqueza alélica a optimizar. Las estrategias empleadas han proporcionado núcleos optimizados con grandes diferencias en la diversidad conservada, así como en el nivel de representación de la estructura genética general. Teniendo en cuenta el uso principal de la colección nuclear, la estrategia que ofrece un mejor equilibrio entre representatividad y adecuación al uso es la que combina la optimización de la distancia media entre cada accesión de la colección y la entrada en el núcleo más cercana con el índice de Shannon y la recuperación de alelos.Este trabajo ha sido financiado por los proyectos INIA RF2011-00017-C05-00 y RTA2015-00052-C02-00Peer reviewe
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