Evaluación de la capacidad antifúngica de pinturas de base acuosa formuladas con aditivos biocidas basados en cationes metálicos estabilizados en matrices zeolíticas

En este trabajo se formularon pinturas de base acuosa para mampostería incorporando como aditivo biocida una zeolita tipo A intercambiada con Ag+1 y/o Zn+2. La eficiencia biocida de los recubrimientos se evaluó frente a A. niger. En primera instancia, se realizó la síntesis de zeolita sódica tipo A (estructura LTA), la cual fue caracterizada a través de difracción de rayos X (XRD) y microscopía electrónica de barrido (SEM). Los cationes biocidas Ag+1 y/o Zn+2 se incorporaron de manera controlada en las cavidades de la matriz aluminosilícea por intercambio catiónico, obteniéndose muestras zeolíticas con contenido variable de estos cationes biocidas. Se determinó la concentración mínima inhibitoria de las zeolitas intercambiadas frente a A. niger con el fin de hallar los valores de intercambio que provean actividad antifúngica eficiente a las pinturas de base acuosa diseñadas. Finalmente se realizó un ensayo de inhibición del crecimiento microbiológico sobre sustratos pintados. Los resultados indican que los cationes biocidas Ag+1 y Zn+2 incorporados en las cajas zeolíticas del tipo LTA podrían ser una herramienta beneficiosa para el desarrollo de recubrimientos de base acuosa ya que proporcionan una protección eficiente contra el ataque microbiológico en comparación con biocidas orgánicos tradicionales cuyos efectos contaminantes han sido altamente investigados y reconocidos.Facultad de Ciencias Exacta

Evaluación de la capacidad antifúngica de pinturas de base acuosa formuladas con aditivos biocidas basados en cationes metálicos estabilizados en matrices zeolíticas

En este trabajo se formularon pinturas de base acuosa para mampostería incorporando como aditivo biocida una zeolita tipo A intercambiada con Ag+1 y/o Zn+2. La eficiencia biocida de los recubrimientos se evaluó frente a A. niger. En primera instancia, se realizó la síntesis de zeolita sódica tipo A (estructura LTA), la cual fue caracterizada a través de difracción de rayos X (XRD) y microscopía electrónica de barrido (SEM). Los cationes biocidas Ag+1 y/o Zn+2 se incorporaron de manera controlada en las cavidades de la matriz aluminosilícea por intercambio catiónico, obteniéndose muestras zeolíticas con contenido variable de estos cationes biocidas. Se determinó la concentración mínima inhibitoria de las zeolitas intercambiadas frente a A. niger con el fin de hallar los valores de intercambio que provean actividad antifúngica eficiente a las pinturas de base acuosa diseñadas. Finalmente se realizó un ensayo de inhibición del crecimiento microbiológico sobre sustratos pintados. Los resultados indican que los cationes biocidas Ag+1 y Zn+2 incorporados en las cajas zeolíticas del tipo LTA podrían ser una herramienta beneficiosa para el desarrollo de recubrimientos de base acuosa ya que proporcionan una protección eficiente contra el ataque microbiológico en comparación con biocidas orgánicos tradicionales cuyos efectos contaminantes han sido altamente investigados y reconocidos.Facultad de Ciencias Exacta

Evaluación de la capacidad antifúngica de pinturas de base acuosa formuladas con aditivos biocidas basados en cationes metálicos estabilizados en matrices zeolíticas

En este trabajo se formularon pinturas de base acuosa para mampostería incorporando como aditivo biocida una zeolita tipo A intercambiada con Ag+1 y/o Zn+2. La eficiencia biocida de los recubrimientos se evaluó frente a A. niger. En primera instancia, se realizó la síntesis de zeolita sódica tipo A (estructura LTA), la cual fue caracterizada a través de difracción de rayos X (XRD) y microscopía electrónica de barrido (SEM). Los cationes biocidas Ag+1 y/o Zn+2 se incorporaron de manera controlada en las cavidades de la matriz aluminosilícea por intercambio catiónico, obteniéndose muestras zeolíticas con contenido variable de estos cationes biocidas. Se determinó la concentración mínima inhibitoria de las zeolitas intercambiadas frente a A. niger con el fin de hallar los valores de intercambio que provean actividad antifúngica eficiente a las pinturas de base acuosa diseñadas. Finalmente se realizó un ensayo de inhibición del crecimiento microbiológico sobre sustratos pintados. Los resultados indican que los cationes biocidas Ag+1 y Zn+2 incorporados en las cajas zeolíticas del tipo LTA podrían ser una herramienta beneficiosa para el desarrollo de recubrimientos de base acuosa ya que proporcionan una protección eficiente contra el ataque microbiológico en comparación con biocidas orgánicos tradicionales cuyos efectos contaminantes han sido altamente investigados y reconocidos.Facultad de Ciencias Exacta

Patterns of post-glacial genetic differentiation in marginal populations of a marine microalga

Peer reviewe

The Changing Landscape for Stroke\ua0Prevention in AF: Findings From the GLORIA-AF Registry Phase 2

Background GLORIA-AF (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients with Atrial Fibrillation) is a prospective, global registry program describing antithrombotic treatment patterns in patients with newly diagnosed nonvalvular atrial fibrillation at risk of stroke. Phase 2 began when dabigatran, the first non\u2013vitamin K antagonist oral anticoagulant (NOAC), became available. Objectives This study sought to describe phase 2 baseline data and compare these with the pre-NOAC era collected during phase 1. Methods During phase 2, 15,641 consenting patients were enrolled (November 2011 to December 2014); 15,092 were eligible. This pre-specified cross-sectional analysis describes eligible patients\u2019 baseline characteristics. Atrial fibrillation disease characteristics, medical outcomes, and concomitant diseases and medications were collected. Data were analyzed using descriptive statistics. Results Of the total patients, 45.5% were female; median age was 71 (interquartile range: 64, 78) years. Patients were from Europe (47.1%), North America (22.5%), Asia (20.3%), Latin America (6.0%), and the Middle East/Africa (4.0%). Most had high stroke risk (CHA2DS2-VASc [Congestive heart failure, Hypertension, Age  6575 years, Diabetes mellitus, previous Stroke, Vascular disease, Age 65 to 74 years, Sex category] score  652; 86.1%); 13.9% had moderate risk (CHA2DS2-VASc = 1). Overall, 79.9% received oral anticoagulants, of whom 47.6% received NOAC and 32.3% vitamin K antagonists (VKA); 12.1% received antiplatelet agents; 7.8% received no antithrombotic treatment. For comparison, the proportion of phase 1 patients (of N = 1,063 all eligible) prescribed VKA was 32.8%, acetylsalicylic acid 41.7%, and no therapy 20.2%. In Europe in phase 2, treatment with NOAC was more common than VKA (52.3% and 37.8%, respectively); 6.0% of patients received antiplatelet treatment; and 3.8% received no antithrombotic treatment. In North America, 52.1%, 26.2%, and 14.0% of patients received NOAC, VKA, and antiplatelet drugs, respectively; 7.5% received no antithrombotic treatment. NOAC use was less common in Asia (27.7%), where 27.5% of patients received VKA, 25.0% antiplatelet drugs, and 19.8% no antithrombotic treatment. Conclusions The baseline data from GLORIA-AF phase 2 demonstrate that in newly diagnosed nonvalvular atrial fibrillation patients, NOAC have been highly adopted into practice, becoming more frequently prescribed than VKA in Europe and North America. Worldwide, however, a large proportion of patients remain undertreated, particularly in Asia and North America. (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients With Atrial Fibrillation [GLORIA-AF]; NCT01468701

Changes in preterm birth and stillbirth during COVID-19 lockdowns in 26 countries.

Preterm birth (PTB) is the leading cause of infant mortality worldwide. Changes in PTB rates, ranging from -90% to +30%, were reported in many countries following early COVID-19 pandemic response measures ('lockdowns'). It is unclear whether this variation reflects real differences in lockdown impacts, or perhaps differences in stillbirth rates and/or study designs. Here we present interrupted time series and meta-analyses using harmonized data from 52 million births in 26 countries, 18 of which had representative population-based data, with overall PTB rates ranging from 6% to 12% and stillbirth ranging from 2.5 to 10.5 per 1,000 births. We show small reductions in PTB in the first (odds ratio 0.96, 95% confidence interval 0.95-0.98, P value <0.0001), second (0.96, 0.92-0.99, 0.03) and third (0.97, 0.94-1.00, 0.09) months of lockdown, but not in the fourth month of lockdown (0.99, 0.96-1.01, 0.34), although there were some between-country differences after the first month. For high-income countries in this study, we did not observe an association between lockdown and stillbirths in the second (1.00, 0.88-1.14, 0.98), third (0.99, 0.88-1.12, 0.89) and fourth (1.01, 0.87-1.18, 0.86) months of lockdown, although we have imprecise estimates due to stillbirths being a relatively rare event. We did, however, find evidence of increased risk of stillbirth in the first month of lockdown in high-income countries (1.14, 1.02-1.29, 0.02) and, in Brazil, we found evidence for an association between lockdown and stillbirth in the second (1.09, 1.03-1.15, 0.002), third (1.10, 1.03-1.17, 0.003) and fourth (1.12, 1.05-1.19, <0.001) months of lockdown. With an estimated 14.8 million PTB annually worldwide, the modest reductions observed during early pandemic lockdowns translate into large numbers of PTB averted globally and warrant further research into causal pathways

Changes in preterm birth and stillbirth during COVID-19 lockdowns in 26 countries.

Preterm birth (PTB) is the leading cause of infant mortality worldwide. Changes in PTB rates, ranging from -90% to +30%, were reported in many countries following early COVID-19 pandemic response measures ('lockdowns'). It is unclear whether this variation reflects real differences in lockdown impacts, or perhaps differences in stillbirth rates and/or study designs. Here we present interrupted time series and meta-analyses using harmonized data from 52 million births in 26 countries, 18 of which had representative population-based data, with overall PTB rates ranging from 6% to 12% and stillbirth ranging from 2.5 to 10.5 per 1,000 births. We show small reductions in PTB in the first (odds ratio 0.96, 95% confidence interval 0.95-0.98, P value <0.0001), second (0.96, 0.92-0.99, 0.03) and third (0.97, 0.94-1.00, 0.09) months of lockdown, but not in the fourth month of lockdown (0.99, 0.96-1.01, 0.34), although there were some between-country differences after the first month. For high-income countries in this study, we did not observe an association between lockdown and stillbirths in the second (1.00, 0.88-1.14, 0.98), third (0.99, 0.88-1.12, 0.89) and fourth (1.01, 0.87-1.18, 0.86) months of lockdown, although we have imprecise estimates due to stillbirths being a relatively rare event. We did, however, find evidence of increased risk of stillbirth in the first month of lockdown in high-income countries (1.14, 1.02-1.29, 0.02) and, in Brazil, we found evidence for an association between lockdown and stillbirth in the second (1.09, 1.03-1.15, 0.002), third (1.10, 1.03-1.17, 0.003) and fourth (1.12, 1.05-1.19, <0.001) months of lockdown. With an estimated 14.8 million PTB annually worldwide, the modest reductions observed during early pandemic lockdowns translate into large numbers of PTB averted globally and warrant further research into causal pathways

Artificial Intelligence-Based Prediction of Cardiovascular Diseases from Chest Radiography

Chest radiography (CXR) is the most frequently performed radiological test worldwide because of its wide availability, non-invasive nature, and low cost. The ability of CXR to diagnose cardiovascular diseases, give insight into cardiac function, and predict cardiovascular events is often underutilized, not clearly understood, and affected by inter- and intra-observer variability. Therefore, more sophisticated tests are generally needed to assess cardiovascular diseases. Considering the sustained increase in the incidence of cardiovascular diseases, it is critical to find accessible, fast, and reproducible tests to help diagnose these frequent conditions. The expanded focus on the application of artificial intelligence (AI) with respect to diagnostic cardiovascular imaging has also been applied to CXR, with several publications suggesting that AI models can be trained to detect cardiovascular conditions by identifying features in the CXR. Multiple models have been developed to predict mortality, cardiovascular morphology and function, coronary artery disease, valvular heart diseases, aortic diseases, arrhythmias, pulmonary hypertension, and heart failure. The available evidence demonstrates that the use of AI-based tools applied to CXR for the diagnosis of cardiovascular conditions and prognostication has the potential to transform clinical care. AI-analyzed CXRs could be utilized in the future as a complimentary, easy-to-apply technology to improve diagnosis and risk stratification for cardiovascular diseases. Such advances will likely help better target more advanced investigations, which may reduce the burden of testing in some cases, as well as better identify higher-risk patients who would benefit from earlier, dedicated, and comprehensive cardiovascular evaluation

Aortic Valve Calcium Score by Computed Tomography as an Adjunct to Echocardiographic Assessment—A Review of Clinical Utility and Applications

Aortic valve stenosis (AS) is increasing in prevalence due to the aging population, and severe AS is associated with significant morbidity and mortality. Echocardiography remains the mainstay for the initial detection and diagnosis of AS, as well as for grading of severity. However, there are important subgroups of patients, for example, patients with low-flow low-gradient or paradoxical low-gradient AS, where quantification of severity of AS is challenging by echocardiography and underestimation of severity may delay appropriate management and impart a worse prognosis. Aortic valve calcium score by computed tomography has emerged as a useful clinical diagnostic test that is complimentary to echocardiography, particularly in cases where there may be conflicting data or clinical uncertainty about the degree of AS. In these situations, aortic valve calcium scoring may help re-stratify grading of severity and, therefore, further direct clinical management. This review presents the evolution of aortic valve calcium score by computed tomography, its diagnostic and prognostic value, as well as its utility in clinical care

Identifying the Causes of Unexplained Dyspnea at High Altitude Using Normobaric Hypoxia with Echocardiography

Exposure to high altitude results in hypobaric hypoxia, leading to physiological changes in the cardiovascular system that may result in limiting symptoms, including dyspnea, fatigue, and exercise intolerance. However, it is still unclear why some patients are more susceptible to high-altitude symptoms than others. Hypoxic simulation testing (HST) simulates changes in physiology that occur at a specific altitude by asking the patients to breathe a mixture of gases with decreased oxygen content. This study aimed to determine whether the use of transthoracic echocardiography (TTE) during HST can detect the rise in right-sided pressures and the impact of hypoxia on right ventricle (RV) hemodynamics and right to left shunts, thus revealing the underlying causes of high-altitude signs and symptoms. A retrospective study was performed including consecutive patients with unexplained dyspnea at high altitude. HSTs were performed by administrating reduced FiO2 to simulate altitude levels specific to patients’ history. Echocardiography images were obtained at baseline and during hypoxia. The study included 27 patients, with a mean age of 65 years, 14 patients (51.9%) were female. RV systolic pressure increased at peak hypoxia, while RV systolic function declined as shown by a significant decrease in the tricuspid annular plane systolic excursion (TAPSE), the maximum velocity achieved by the lateral tricuspid annulus during systole (S’ wave), and the RV free wall longitudinal strain. Additionally, right-to-left shunt was present in 19 (70.4%) patients as identified by bubble contrast injections. Among these, the severity of the shunt increased at peak hypoxia in eight cases (42.1%), and the shunt was only evident during hypoxia in seven patients (36.8%). In conclusion, the use of TTE during HST provides valuable information by revealing the presence of symptomatic, sustained shunts and confirming the decline in RV hemodynamics, thus potentially explaining dyspnea at high altitude. Further studies are needed to establish the optimal clinical role of this physiologic method