261 research outputs found
Collagen organization, polarization sensitivity and image quality in human corneas using second harmonic generation microscopy
In this paper, a Second-Harmonic-Generation (SHG) microscope was used to study the relationship between collagen structural arrangement, image quality and polarization sensitivity in human corneas with different organizations. The degree of order (or alternatively, the Structural Dispersion, SD) was quantified using the structure tensor method. SHG image quality was evaluated with different objective metrics. Dependence with polarization was quantified by means of a parameter defined as polarimetric modulation, which employs polarimetric SHG images acquired with four independent polarization states. There is a significant exponential relationship between the quality of the SHG images and the SD of the samples. Moreover, polarization sensitivity strongly depends on collagen arrangement. For quasi- or partially organized specimens, there is a polarization state that noticeably improves the image quality, providing additional information often not seen in other SHG images. This does not occur in non-organized samples. This fact is closely related to polarimetric modulation, which linearly decreases with the SD. Understanding in more detail the relationships that take place between collagen distribution, image quality and polarization sensitivity brings the potential to enable the development of optimized SHG image acquisition protocols and novel objective strategies for the analysis and detection of pathologies related to corneal collagen disorders, as well as surgery follow-ups
Impact of Physical Activity and Exercise on the Epigenome in Skeletal Muscle and Effects on Systemic Metabolism
Julio Plaza-Diaz and Concepcion M. Aguilera are part of the "UGR Plan Propio de Investigacion 2016" and the "Excellence actions: Unit of Excellence on Exercise and Health (UCEES), University of Granada". Julio Plaza-Diaz is supported by a fellowship to postdoctoral researchers at foreign universities and research centers from the "Fundacion Ramon Areces", Madrid, Spain. Francisco Javier Ruiz-Ojeda is supported by a fellowship from Spanish Government "Agencia Estatal de Investigacion-Juan de la Cierva-Incorporacion" program (IJC2020-042739-I). Alvaro TorresMartos is supported by the Project "Transductores Moleculares del Ejercicio Fisico y la Activacion del Tejido Adiposo Pardo: en Busca de Nuevas Dianas Terapeuticas en la Comunicacion Intercelular" funded by "Consejeria de Economia, Conocimiento, Empresas y Universidad (PY18-4455), Junta de Andalucia", Spain.Exercise and physical activity induces physiological responses in organisms, and adaptations
in skeletal muscle, which is beneficial for maintaining health and preventing and/or treating
most chronic diseases. These adaptations are mainly instigated by transcriptional responses that
ensue in reaction to each individual exercise, either resistance or endurance. Consequently, changes
in key metabolic, regulatory, and myogenic genes in skeletal muscle occur as both an early and late
response to exercise, and these epigenetic modifications, which are influenced by environmental and
genetic factors, trigger those alterations in the transcriptional responses. DNA methylation and histone
modifications are the most significant epigenetic changes described in gene transcription, linked
to the skeletal muscle transcriptional response to exercise, and mediating the exercise adaptations.
Nevertheless, other alterations in the epigenetics markers, such as epitranscriptomics, modifications
mediated by miRNAs, and lactylation as a novel epigenetic modification, are emerging as key events
for gene transcription. Here, we provide an overview and update of the impact of exercise on
epigenetic modifications, including the well-described DNA methylations and histone modifications,
and the emerging modifications in the skeletal muscle. In addition, we describe the effects of exercise
on epigenetic markers in other metabolic tissues; also, we provide information about how systemic
metabolism or its metabolites influence epigenetic modifications in the skeletal muscle."Fundacion Ramon Areces", Madrid, SpainSpanish Government "Agencia Estatal de Investigacion-Juan de la Cierva-Incorporacion" program IJC2020-042739-IProject "Transductores Moleculares del Ejercicio Fisico y la Activacion del Tejido Adiposo Pardo: en Busca de Nuevas Dianas Terapeuticas en la Comunicacion Intercelular" - "Consejeria de Economia, Conocimiento, Empresas y Universidad, Junta de Andalucia", PY18-445
Aplicación de medidas de linealidad del gráfico p-p al problema de dos muestras
Se presenta un estadístico no-paramétrico para el problema de dos muestras, basado en una medida de linealidad del gráfico P-P. El estadístico propuesto es la adaptación de una idea bien conocida en la literatura en el contexto de bondad de ajuste a una familia paramétrica. Se lleva a cabo una comparación Monte Carlo con los métodos clásicos de Wilcoxon y Ansari-Bradley, Kolmogorov-Smirnov y Cramér-von Mises para el probelam de dos muestras. Dicha comparación demuestra que el método propuesto ofrece uma potencia superior frente a ciertas alternativas relevantes. Desde el punto de vista teórico, se estudia la consistencia del método propuesto y se establece un Teorema del Límite Central para su distribución.We present a non-parametric statistic based on a linearity measure of the P-P plot for the two-sample problem by adapting a known statistic proposed for goodness of fit to a univariate parametric family. A Monte Carlo comparison is carried out to compare the method proposed with the classical Wilcoxon and Ansari-Bradley statistics and the Kolmogorov-Smirnov and Cramér-von Mises statistics the two-sample problem, showing that, for certain relevant alternatives, the proposed method offers advantages, in terms of power, over its classical counterparts. Theoretically, the consistency of the statistic proposed is studied and a Central Limit Theorem is established for its distribution
Gender differences in clinical presentation and 1-year outcomes in atrial fibrillation
Objectives Our objective was to examine gender differences in clinical presentation, management and prognosis of atrial fibrillation (AF) in a contemporary cohort.
Methods In 6412 patients, 39.7% women, of the PREvention oF thromboembolic events – European Registry in Atrial Fibrillation, we examined gender differences in symptoms, risk factors, therapies and 1-year incidence of adverse outcomes.
Results Men with AF were on average younger than women (mean±SD: 70.1±10.7 vs 74.1±9.7 years, p<0.0001). Women more frequently had at least one AF-related symptom at least occasionally compared with men (95.4% in women, 89.8% in men, p<0.0001). Prescription of oral anticoagulation was similar, with an increase of non-vitamin K antagonist oral anticoagulants from 5.9% to 12.6% in women and from 6.2% to 12.6% in men, p<0.0001 for both.
Men were more frequently treated with electrical cardioversion and ablation (20.6% and 6.3%, respectively) than women (14.9% and 3.3%, respectively), p<0.0001. Women had 65% (OR: 0.35; 95% CI (0.22 to 0.56)) lower age-adjusted and country-adjusted odds of coronary revascularisation, 40% (OR: 0.60; (0.38 to 0.93)) lower odds of acute coronary syndrome and 20% (OR: 0.80; (0.68 to 0.96)) lower odds of heart failure at 1 year. There were no statistically significant gender differences in 1-year stroke/transient ischaemic attack/arterial thromboembolism and major bleeding events.
Conclusion In a ‘real-world’ European AF registry, women were more symptomatic but less likely to receive invasive rhythm control therapy such as electrical cardioversion or ablation. Further study is needed to confirm that these differences do not disadvantage women with AF
High-intensity high-volume swimming induces more robust signaling through PGC-1α and AMPK activation than sprint interval swimming in <i>m. triceps brachii</i>
We aimed to test whether high-intensity high-volume training (HIHVT) swimming would induce more robust signaling than sprint interval training (SIT) swimming within the m. triceps brachii due to lower metabolic and oxidation. Nine well-trained swimmers performed the two training procedures on separate randomized days. Muscle biopsies from m. triceps brachii and blood samples were collected at three different time points: a) before the intervention (pre), b) immediately after the swimming procedures (post) and c) after 3 h of rest (3 h). Hydroperoxides, creatine kinase (CK), and lactate dehydrogenase (LDH) were quantified from blood samples, and peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) and the AMPKpTHR172/AMPK ratio were quantified by Western blot analysis. PGC-1α, sirtuin 3 (SIRT3), superoxide-dismutase 2 (SOD2), and vascular endothelial growth factor (VEGF) mRNA levels were also quantified. SIT induced a higher release of LDH (
Intake of slow-digesting carbohydrates is related to changes in the microbiome and its functional pathways in growing rats with obesity induced by diet
Introduction: The main cause of insulin resistance in childhood is obesity,
which contributes to future comorbidities as in adults. Although high-calorie
diets and lack of exercise contribute to metabolic disease development, food
quality rather than the quantity of macronutrients is more important than
food density. The purpose of the present study was to examine the effects
of changing the quality of carbohydrates from rapidly to slowly digestible
carbohydrates on the composition of the gut microbiota and the profiles of
the functional pathways in growing rats with obesity due to a high-fat diet
(HFD).
Methods: During the course of 4 weeks, rats growing on an HFD-containing
carbohydrates with different digestive rates were fed either HFD-containing
carbohydrates with a rapid digestion rate (OBE group) or HFD-containing
carbohydrates with a slow digestion rate (OBE-ISR group). A non-obese group
(NOB) was included as a reference, and rats were fed on a rodent standard diet
(AIN93G). An analysis of gut microbiota was conducted using 16S rRNA-based
metagenomics; a linear mixed-effects model (LMM) was used to determine
changes in abundance between baseline and 4 weeks of treatment, and
functional pathways were identified. Gut microbiota composition at bacterial
diversity and relative abundance, at phylum and genus levels, and functional profiles were analyzed by integrating the Integrated Microbial Genomes (IMG)
database.
Results: The groups showed comparable gut microbiota at baseline.
At the end of the treatment, animals from the ISR group exhibited
differences at the phylum levels by decreasing the diversity of Fisher’s
index and Firmicutes (newly named as Bacillota), and increasing the Pielou’s
evenness and Bacteroidetes (newly named as Bacteroidota); at the genus
level by increasing Alistipes, Bifidobacterium, Bacteroides, Butyricimonas,
Lachnoclostridium, Flavonifractor, Ruminiclostridium 5, and Faecalibaculum
and decreasing Muribaculum, Blautia, and Ruminiclostridium 9. Remarkably,
relative abundances of genera Tyzzerella and Angelakisella were higher in
the OBE group compared to NOB and OBE-ISR groups. In addition, some
microbiota carbohydrate metabolism pathways such as glycolysis, glucuronic
acid degradation, pentose phosphate pathway, methanogenesis, and fatty
acid biosynthesis exhibited increased activity in the OBE-ISR group after the
treatment. Higher levels of acetate and propionate were found in the feces of
the ISR group compared with the NOB and OBE groups.
Conclusion: The results of this study demonstrate that replacing rapidly
digestible carbohydrates with slowly digestible carbohydrates within an HFD
improve the composition of the gut microbiota. Consequently, metabolic
disturbances associated with obesity may be prevented.Abbott Laboratories S.A"Fundacion Ramon Areces", Madrid, Spai
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