606 research outputs found
Predicting Atrial Fibrillation Recurrence After Catheter Ablation Through Time Variability of P-wave Features
[EN] Nowadays, the first-line therapy for paroxysmal atrial fibrillation (PAF) is pulmonary vein isolation through catheter ablation. However, the success rate of this procedure is still not as high as desirable. Thus, preoperative prediction of early AF recurrence after ablation is a challenge to select optimal candidates for the intervention. To this end, some promising predictors based on the P-wave in short ECG signals have been proposed in the last years. However, evolution of the P-wave along the time has still not been analyzed. Hence, the present work studies how time variability of two features of the P-wave predicts midterm cryoablation failure. For 45 PAF patients, a standard 12-lead ECG signal was obtained for 5 minutes before ablation. An automatic algorithm was then used to delineate all P-waves in lead II, and duration and amplitude were computed. The resulting time series were characterized by their mean, standard deviation and coefficient of variation (CV). Correlating these measures with ablation outcome, the CV for both parameters obtained the best discrimination between patients. In fact, compared with the mean value, the CV for both features obtained accuracies 10% greater, thus achieving values of 70%. These outcomes entail that time variability of the P-wave can reveal new information about the proarrhythmic condition of the patients, thus improving predictions of ablation failure.Ruiz, A.; Arias, MA.; Puchol, A.; Pachon, MI.; Rieta, JJ.; Alcaraz, R. (2020). Predicting Atrial Fibrillation Recurrence After Catheter Ablation Through Time Variability of P-wave Features. IEEE. 1-4. https://doi.org/10.22489/CinC.2020.366S1
Observation of spontaneous self-channelling of light in air below the collapse threshold
We report the observation of the self-guided propagation of 120 fs, 0.56 mJ
infrared radiation in air for distances greater than one meter. In contrast to
the known case of filamentation, in the present experiment the laser power is
lower than the collapse threshold. Therefore the counter balance between Kerr
self focussing and ionization induced defocussing as the stabilizing mechanism
is ruled out. Instead, we find evidences of a process in which the transversal
beam distribution reshapes into a form similar to a Townes soliton. We include
numerical support for this conclusion
Myopic maculopathy: Current status and proposal for a new classification and grading system (ATN)
Myopia is a highly frequent ocular disorder worldwide and pathologic myopia is the 4th most common cause of irreversible blindness in developed countries. Pathologic myopia is especially common in East Asian countries. Ocular alterations associated with pathologic myopia, especially those involving the macular area—defined as myopic maculopathy—are the leading causes of vision loss in patients with pathologic myopia.
High myopia is defined as the presence of a highly negative refractive error (>−6 to −8 diopters) in the context of eye elongation (26–26.5 mm). Although the terms high myopia and pathologic myopia are often used interchangeably, they do not refer to the same eye disease. The two key factors driving the development of pathologic myopia are: 1) elongation of the axial length and 2) posterior staphyloma.
The presence of posterior staphyloma, which is the most common finding in patients with pathologic myopia, is the key differentiating factor between high and pathologic myopia. The occurrence of staphyloma will, in most cases, eventually lead to other conditions such as atrophic, traction, or neovascular maculopathy. Posterior staphyloma is for instance, responsible for the differences between a myopic macular hole (MH)—with and without retinal detachment—and idiopathic MH. Posterior staphyloma typically induces retinal layer splitting, leading to foveoschisis in myopic MH, an important differentiating factor between myopic and emmetropic MH.
Myopic maculopathy is a highly complex disease and current classification systems do not fully account for the numerous changes that occur in the macula of these patients. Therefore, a more comprehensive classification system is needed, for several important reasons. First, to more precisely define the disease stage to improve follow-up by enabling clinicians to more accurately monitor changes over time, which is essential given the progressive nature of this condition. Second, unification of the currently-available classification systems would establish standardized classification criteria that could be used to compare the findings from international multicentric studies. Finally, a more comprehensive classification system could help to improve our understanding of the genetic origins of this disease, which is clearly relevant given the interchangeable—but erroneous—use of the terms high and pathologic myopia in genetic researc
Lavandin essential oil combined with the biopolymer PHBV, poly(3-hydroxybutyrate-co-3-hydroxyvalerate), for wound treatment
In this work, poly(3-hydroxybutyrate-co-3-hydroxyvalerate), PHBV, was combined with lavandin essential oil (LavEO), from Lavandula hybrida grown in Argentina. Linalool (36%), linalyl acetate (29%) 1,8-cineole (6%) and camphor (6%) were its main compounds as analyzed by GC-MS. PHBV is a biodegradable copolyester from a bacterial source; PHBV porous scaffolds have been shown to be suitable for fibroblast and keratinocyte proliferation [1,2] and thus for skin regeneration. In addition, LavEO exhibits strong anti-inflammatory and antibacterial activity, what improves wound healing [4,5]. Purified monoterpenes and entire EOs have been combined with other biopolymers for different applications but scarcely for wound healing and never previously with PHBV [6]. PHBV porous membranes, 100-200 µm thickness, containing LavEO at 2, 4 or 8% m/m were obtained by an emulsion-solvent evaporation method. LavEO-PHBV membranes did not show cytotoxicity when tested on NIH/3T3 fibroblasts (according to the ISO 10993-5 standard). SEM membrane analysis showed, in all cases, a high level of porosity, ̴ 20% of the surface. Keratinocytes (KC) adhesion and proliferation were evaluated with the HaCaT cell line. Membranes containing 2 or 4% of LavEO, allowed KC proliferation of the same level as that of PHBV membrane controls. However, cells neither adhered to nor proliferated on membranes with 8% LavEO although their hydrophobicity, estimated by the contact angle, was similar to that of 4%-LavEO membranes. The reduction in the elastic modulus–determined by the dynamic mechanical analysis–due to the presence of LavEO, suggests its plasticizer effect (control E=305±10 MPa; 8%-LavEO membrane E=150±20 MPa). According to these results, 2 or 4% LavEO-PHBV membranes seem as a promising treatment, especially in the case of infected and chronic wounds, often arrested at the inflammatory phase
Skin Cancer Prevalence in Outdoor Workers of Ski Resorts
Background. Snow reflectivity and altitude increase the exposure of ski resort workers to solar ultraviolet radiation. The aim was to assess the presence of skin cancer in ski resorts workers and compare it with other groups of outdoor workers reviewing published studies. Methods. An observational cross-sectional prospective study was conducted in the three largest ski resorts in Spain: Baqueira Beret, Lleida; Formigal, Huesca and Sierra Nevada, Granada. All outdoor workers including ski instructors were invited to participate in the study. The participants completed a validated questionnaire about sun exposure and underwent a skin examination. Results. 219 workers were included in the study (80% male; mean age 43.8 (SD 11.31) years). Actinic keratosis (AK) but no other skin cancers were detected in 32 participants (14.62%). Those with AK worked in the Southernmost ski resort, were more likely to have light colour hair, and were older and with higher photoaging grade than those without them. Conclusion. Compared to other studies, outdoor workers on ski resorts show a higher prevalence of AK than general population but a lower prevalence than other groups of outdoor workers. © 2020 Yolanda Gilaberte et al
Evaluación de los recursos solares en el sur de la Península utilizando el modelo MM5
Ponencia presentada en: XXIX Jornadas Científicas de la AME y el VII Encuentro Hispano Luso de Meteorología celebrado en Pamplona, del 24 al 26 de abril de 2006
Identification of the most vulnerable populations in the psychosocial sphere: a cross-sectional study conducted in Catalonia during the strict lockdown imposed against the COVID-19 pandemic.
Design and objectives A cross-sectional study to evaluate the impact of COVID-19 on the psychosocial sphere in both the general population and healthcare workers (HCWs). Methods The study was conducted in Catalonia (Spain) during the first wave of the COVID-19 pandemic when strict lockdown was in force. The study population included all people aged over 16 years who consented to participate in the study and completed the survey, in this case a 74-question questionnaire shared via social media using snowball sampling. A total of 56 656 completed survey questionnaires were obtained between 3 and 19 April 2020. The primary and secondary outcome measures included descriptive statistics for the non-psychological questions and the psychological impact of the pandemic, such as depression, anxiety, stress and post-traumatic stress disorder question scores. Results A n early and markedly negative impact on family finances, fear of working with COVID-19 patients and ethical issues related to COVID-19 care among HCWs was observed. A total of seven target groups at higher risk of impaired mental health and which may therefore benefit from an intervention were identified, namely women, subjects aged less than 42 years, people with a care burden, socioeconomically deprived groups, people with unskilled or unqualified jobs, patients with COVID-19 and HCWs working with patients with COVID-19. Conclusions Active implementation of specific strategies to increase resilience and to prepare an adequate organisational response should be encouraged for the seven groups identified as high risk and susceptible to benefit from an intervention
Markers of endothelial damage in patients with chronic kidney disease on hemodialysis
Patients with Stage 5 chronic kidney disease who are on hemodialysis (HD) remain in a chronic inflammatory state, characterized by the accumulation of uremic toxins that induce endothelial damage and cardiovascular disease (CVD). Our aim was to examine microvesicles (MVs), monocyte subpopulations, and angiopoietins (Ang) to identify prognostic markers in HD patients with or without diabetes mellitus (DM). A total of 160 prevalent HD patients from 10 centers across Spain were obtained from the Biobank of the Nephrology Renal Network (Madrid, Spain): 80 patients with DM and 80 patients without DM who were matched for clinical and demographic criteria. MVs from plasma and several monocyte subpopulations (CD142+/CD16+, CD14+/CD162+) were analyzed by flow cytometry, and the plasma concentrations of Ang1 and Ang2 were quantified by ELISA. Data on CVD were gathered over the 5.5 yr after these samples were obtained. MV level, monocyte subpopulations (CD14+/CD162+ and CD142+/CD16+), and Ang2-to-Ang1 ratios increased in HD patients with DM compared with non-DM patients. Moreover, MV level above the median (264 MVs/µl) was associated independently with greater mortality. MVs, monocyte subpopulations, and Ang2-to-Ang1 ratio can be used as predictors for CVD. In addition, MV level has a potential predictive value in the prevention of CVD in HD patients. These parameters undergo more extensive changes in patients with DM.Support for this work was provided by Plan Nacional de IDi Proyectos de Investigación en Salud of Instituto de Salud Carlos III (ISCIII)–Subdirección General de Evaluación, Fondos de desarrollo regional (FEDER; PI11/01536, PI12/01489, PI14/00806, PI15/01785); Junta de Andalucía grants (P010-CTS-6337, P11-CTS-7352); and Fundación Nefrológica. P. Buendía, A.
Carmona, and C. Luna-Ruiz are fellows from Consejería de Innovacion, Ciencia y Empresa, Junta de Andalucía
Unravelling the mechanisms that determine the uptake and metabolism of magnetic single and multicore nanoparticles in a Xenopus laevis model.
Multicore superparamagnetic nanoparticles have been proposed as ideal tools for some biomedical applications because of their high magnetic moment per particle, high specific surface area and long term colloidal stability. Through controlled aggregation and packing of magnetic cores it is possible to obtain not only single-core but also multicore and hollow spheres with internal voids. In this work, we compare toxicological properties of single and multicore nanoparticles. Both types of particles showed moderate in vitro toxicity (MTT assay) tested in Hep G2 (human hepatocellular carcinoma) and Caco-2 (human colorectal adenocarcinoma) cells. The influence of surface chemistry in their biological behavior was also studied after functionalization with O,O′-bis(2-aminoethyl) PEG (2000 Da). For the first time, these nanoparticles were evaluated in a Xenopus laevis model studying their whole organism toxicity and their impact upon iron metabolism. The degree of activation of the metabolic pathway depends on the size and surface charge of the nanoparticles which determine their uptake. The results also highlight the potential of Xenopus laevis model bridging the gap between in vitro cell-based assays and rodent models for toxicity assessment to develop effective nanoparticles for biomedical applications
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