11,409 research outputs found

    Gap junction reduction in cardiomyocytes following transforming growth factor- beta treatment and Trypanosoma cruzi infection

    Get PDF
    Gap junction connexin-43 (Cx43) molecules are responsible for electrical impulse conduction in the heart and are affected by transforming growth factor-beta (TGF-beta). This cytokine increases during Trypanosoma cruzi infection, modulating fibrosis and the parasite cell cycle. We studied Cx43 expression in cardiomyocytes exposed or not to TGF-beta T. cruzi, or SB-431542, an inhibitor of TGF-beta receptor type I (ALK-5). Cx43 expression was also examined in hearts with dilated cardiopathy from chronic Chagas disease patients, in which TGF-beta signalling had been shown previously to be highly activated. We demonstrated that TGF-beta treatment induced disorganised gap junctions in non-infected cardiomyocytes, leading to a punctate, diffuse and non-uniform Cx43 staining. A similar pattern was detected in T. cruzi-infected cardiomyocytes concomitant with high TGF-beta secretion. Both results were reversed if the cells were incubated with SB-431542. Similar tests were performed using human chronic chagasic patients and we confirmed a down-regulation of Cx43 expression, an altered distribution of plaques in the heart and a significant reduction in the number and length of Cx43 plaques, which correlated negatively with cardiomegaly. We conclude that elevated TGF-beta levels during T. cruzi infection promote heart fibrosis and disorganise gap junctions, possibly contributing to abnormal impulse conduction and arrhythmia that characterise severe cardiopathy in Chagas disease

    Therapeutic Art for Individuals with Multiple Sclerosis

    Get PDF
    Introduction: Depression is more prevalent in individuals with MS than in the average population, which presents complications of quality of life beyond simply the primary disease process. This project aims to explore the immediate emotional benefits of therapeutic art sessions for individuals with MS, in addition to exploring the feasibility of reducing concomitant depression in this population with therapeutic art alongside standard medical therapy. Methods: Therapeutic art sessions were held with 3 support groups of 5 to 12 individuals with MS. Participants were initially prompted with a writing exercise regarding how they perceive themselves, and then prompted to paint a self-portrait using their writing as a guide. Each participant produced 1 painting per session, with many participants engaging in multiple sessions across time. Acrylic paint was used in order to allow participants of all levels of motor function, dexterity, and artistic skill to participate. Results: The products ranged from literal portraits of participants’ faces to interpretive pieces of what it feels like to live with MS. During the therapeutic sessions, participants reflected on their experience living with MS and expressed the resurfaced emotions in their paintings, as well as during debrief discussions. The pieces were presented at the Philadelphia MS Breakthroughs Conference, where not only the project was appreciated by members of the MS community but interest in the continuation of the project was expressed. Discussion: The results from this project demonstrate the immediate benefits of therapeutic art sessions for participants of the study whose involvement produced meaningful, emotional experiences. Moving forward, the greater MS community expressed positivity towards the project and support for its future expansion which will explore not only the feasibility of therapeutic art sessions but additionally its measured clinical effects on depression, aiming to validate the use of therapeutic art for depression with MS

    Distinguishing Healthy Ageing from Dementia: A Biomechanical Simulation of Brain Atrophy Using Deep Networks

    Get PDF
    Biomechanical modeling of tissue deformation can be used to simulate different scenarios of longitudinal brain evolution. In this work, we present a deep learning framework for hyper-elastic strain modelling of brain atrophy, during healthy ageing and in Alzheimer’s Disease. The framework directly models the effects of age, disease status, and scan interval to regress regional patterns of atrophy, from which a strain-based model estimates deformations. This model is trained and validated using 3D structural magnetic resonance imaging data from the ADNI cohort. Results show that the framework can estimate realistic deformations, following the known course of Alzheimer’s disease, that clearly differentiate between healthy and demented patterns of ageing. This suggests the framework has potential to be incorporated into explainable models of disease, for the exploration of interventions and counterfactual examples

    Cardiovascular Risk Awareness, Treatment, and Control in Urban Latin America

    Get PDF
    on behalf of the CARMELA Study Investigators Effective prevention and treatment of cardiovascular diseases require regular screening for risk factors, high awareness of the condition, effective treatment of the identified risk factors, and adherence to the prescribed treatment. The Cardiovascular Risk Factor Multiple Evaluation in Latin America study was a cross-sectional, population-based, observational study of major cardiovascular risk factors-including hypertension, diabetes, and hypercholesterolemia-in 7 Latin American cities. This report presents data on assessment, diagnosis, extent, and effectiveness of treatment, adherence to treatment, and reasons for nonadherence. Data were collected through household questionnaire-based interviews administered to 5383 men and 6167 women, 25-64 years of age, living in the following cities: Barquisimeto, Venezuela; Bogota, Colombia; Buenos Aires, Argentina; Lima, Peru; Mexico City, Mexico; Quito, Ecuador; and Santiago, Chile. Participants also completed a clinic visit for anthromorphometric and laboratory assessments. Rates of prior diagnosis of hypertension and diabetes were high (64% and 78% of affected individuals, respectively) but relatively low for hypercholesterolemia (41%). The majority of affected individuals (hypercholesterolemia 88%, diabetes 67%, and hypertension 53%) were untreated. Among individuals who were receiving pharmacologic treatment, targets for control of hypertension, diabetes, and hypercholesterolemia were achieved by 51%, 16%, and 52%, respectively. Adherence to treatment was observed in 69% of individuals with hypertension, 63% with diabetes, and 66% with hypercholesterolemia. Forgetfulness was the major cause of nonadherence for all 3 conditions. There is a substantial need for increasing patient education, diagnosis, treatment, adherence, and control of cardiovascular risk factors in the 7 Latin American cities. Keywords: adherence, awareness, blood pressure, cardiovascular risk factors, diabetes, hypercholesterolemia, hypertension, treatment control CLINICAL SIGNIFICANCE (1) Although a majority of individuals knew they had hypertension or diabetes, only 41% were aware of hypercholesterolemia. (2) Forty-seven percent of hypertensive, 33% of diabetic, and 12% of hypercholesterolemic individuals were receiving pharmacological treatment, yet control of these conditions was low

    Evaluation of the postharvest quality of Cagaita fruits (Eugenia dysenterica DC.) coated with chitosan and associated with refrigeration

    Get PDF
    Cagaita fruits are subject to seasonality and perishability. This work aims to use scanning electron microscopy (SEM) to evaluate the physicochemical characteristics, texture, color and physical structure of cagaita fruits coated with different chitosan concentrations. The fruits were divided as follows: T0 (uncoated fruits), T1 (fruits coated with 1% (v/v) chitosan), T2 (fruits coated with 2% (v/v) chitosan) and T3 (fruits coated with 3% (v/v) chitosan). They were analyzed at 0, 10, 20 and 30 days of storage. Titratable acidity and soluble solids content showed no conservation of fruit characteristics; they showed better results for uncoated fruits, as well as weight loss, vitamin C and peak strain. The color of cagaita fruits confirmed ripening during storage regardless of treatment. Scanning electron microscopy showed that the film solution did not adhere, as desired, to the cell wall of fruits. As the results of fruits coated with 3% pectin were close to control, further studies should be carried out with higher coating percentages so that the fruit quality is maintained during storage.Keywords: Physical structure, film solution, quality, shelf life

    Thermal stability of nanoporous raney gold catalyst

    Get PDF
    © 2015 by the authors; licensee MDPI, Basel, Switzerland. Nanoporous “Raney gold” sponge was prepared by de-alloying an Au-Al precursor alloy. Catalytic tests using a micro-reactor confirmed that Raney gold can serve as an active heterogeneous catalyst for CO oxidation, reduction of NO to N2, and oxidation of NO to NO2. In general, the specific surface area of a heterogeneous catalyst has an influence on its catalytic efficacy. Unfortunately, gold sponges coarsen readily, leading to sintering of their structure and reduction in surface area. This potentially places constraints on their upper operating temperature in catalytic reactors. Here we analyzed the behavior of Raney gold when the temperature was raised. We examined the kinetics and mechanism of coarsening of the sponge using a combination of in situoptical measurements and Metropolis Monte Carlo modeling with a Lennard-Jones interatomic potential. Modeling showed that the sponges started with an isotropic “foamy” morphology with negative average “mean curvature” but that subsequent thermally activated coarsening will drive the morphology through a bi-continuous fibrous state and on, eventually, to a sponge consisting of sintered blobs of predominantly positive “mean curvature”
    • 

    corecore