Predictors of exercise capacity in dilated cardiomyopathy with focus on pulmonary venous flow recorded with transesophageal eco-doppler

The aim of this study was to clarify the relative contribution of elevated left ventricle (LV) filling pressure (FP) estimated by pulmonary venous (PV) and mitral flow, transesophageal Doppler recording (TEE), and other extracardiac factors like obesity and renal insufficiency (KI) to exercise capacity (ExC) evaluated by cardiopulmonary exercise testing (CPX) in patients with dilated cardiomyopathy (DCM). During the CPX test, 119 patients (pts) with DCM underwent both peak VO2 consumption and then TEE with color-guided pulsed-wave Doppler recording of PVF and transmitral flow. In 78 patients (65%), peak VO2 was normal or mildly reduced (>14 mL/kg/min) (group 1) while it was markedly reduced (≤14 mL/kg/min) in 41 (group 2). In univariate analysis, systolic fraction (S Fract), a predictor of elevated pre-a LV diastolic FP, appeared to be the best diastolic parameter predicting a significantly reduced peak VO2. Logistic regression analysis identi-fied five parameters yielding a unique, statistically significant contribution in predicting reduced ExC: creatinine clearance < 52 mL/min (odds ratio (OR) = 7.4, p = 0.007); female gender (OR = 7.1, p = 0.004); BMI > 28 (OR = 5.8, p = 0.029), age > 62 years (OR = 5.5, p = 0.03), S Fract < 59% (OR = 4.9, p = 0.02). Conclusion: KI was the strongest predictor of reduced ExC. The other modifiable factors were obesity and severe LV diastolic dysfunction expressed by blunted systolic venous flow. Contrar-ily, LV ejection fraction was not predictive, confirming other previous studies. This has important clinical implications

Cardiac and arrhythmic complications in patients with COVID-19

In December 2019, the world started to face a new pandemic situation, the severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2). Although coronavirus disease (COVID-19) clinical manifestations are mainly respiratory, major cardiac complications are being reported. Cardiac manifestations etiology seems to be multifactorial, comprising direct viral myocardial damage, hypoxia, hypotension, enhanced inflammatory status, ACE2-receptors downregulation, drug toxicity, endogenous catecholamine adrenergic status, among others. Studies evaluating patients with COVID-19 presenting cardiac injury markers show that it is associated with poorer outcomes, and arrhythmic events are not uncommon. Besides, drugs currently used to treat the COVID-19 are known to prolong the QT interval and can have a proarrhythmic propensity. This review focus on COVID-19 cardiac and arrhythmic manifestations and, in parallel, makes an appraisal of other virus epidemics as SARS-CoV, Middle East respiratory syndrome coronavirus, and H1N1 influenza

A structure-based proposal for the catalytic mechanism of the bacterial acid phosphatase AphA belonging to the DDDD superfamily of phosphohydrolases

The Escherichia coli gene aphA codes for a periplasmic acid phosphatase called AphA, belonging to class B bacterial phosphatases, which is part of the DDDD superfamily of phosphohydrolases. After our first report about its crystal structure, we have started a series of crystallographic studies aimed at understanding of the catalytic mechanism of the enzyme. Here, we report three crystal structures of the AphA enzyme in complex with the hydrolysis products of nucleoside monophosphate substrates and a fourth with a proposed intermediate analogue that appears to be covalently bound to the enzyme. Comparison with the native enzyme structure and with the available X-ray structures of different phosphatases provides clues about the enzyme chemistry and allows us to propose a catalytic mechanism for AphA, and to discuss it with respect to the mechanism of other bacterial and human phosphatases. (c) 2005 Elsevier Ltd. All rights reserved

VINYL: Variant prIoritizatioN bY survivaL analysis

Motivation: Clinical applications of genome re\uadsequencing technologies typically generate large amounts of data that need to be carefully annotated and interpreted to identify genetic variants associated with pathological conditions. In this context, accurate and reproducible methods for the functional annotation and prioritization of genetic variants are of fundamental importance, especially when large volumes of data \uad like those produced by modern sequencing technologies \uad are involved. Results: In this paper, we present VINYL, a highly accurate and fully automated system for the functional annotation and prioritization of genetic variants in large scale clinical studies. Extensive analyses of both real and simulated datasets suggest that VINYL show higher accuracy and sensitivity when compared to equivalent state of the art methods, allowing the rapid and systematic identification of potentially pathogenic variants in different experimental settings

Functional study of a KCNH2 mutant: Novel insights on the pathogenesis of the LQT2 syndrome

The K+ voltage-gated channel subfamily H member 2 (KCNH2) transports the rapid component of the cardiac delayed rectifying K+ current. The aim of this study was to characterize the biophysical properties of a C-terminus-truncated KCNH2 channel, G1006fs/49 causing long QT syndrome type II in heterozygous members of an Italian family. Mutant carriers underwent clinical workup, including 12-lead electrocardiogram, transthoracic echocardiography and 24-hour ECG recording. Electrophysiological experiments compared the biophysical properties of G1006fs/49 with those of KCNH2 both expressed either as homotetramers or as heterotetramers in HEK293 cells. Major findings of this work are as follows: (a) G1006fs/49 is functional at the plasma membrane even when co-expressed with KCNH2, (b) G1006fs/49 exerts a dominant-negative effect on KCNH2 conferring specific biophysical properties to the heterotetrameric channel such as a significant delay in the voltage-sensitive transition to the open state, faster kinetics of both inactivation and recovery from the inactivation and (c) the activation kinetics of the G1006fs/49 heterotetrameric channels is partially restored by a specific KCNH2 activator. The functional characterization of G1006fs/49 homo/heterotetramers provided crucial findings about the pathogenesis of LQTS type II in the mutant carriers, thus providing a new and potential pharmacological strategy

Decreased point prevalence of Haemophilus influenzae type b (Hib) oropharyngeal colonization by mass immunization of Brazilian children less than 5 years old with Hib polyribosylribitol phosphate polysaccharide-tetanus toroid conjugate vaccine in combination with diphtheria-tetanus toxoids-pertussis vaccine

A protective herd effect has been described after susceptible populations of children are vaccinated with conjugate Haemophilus influenzae type b (Hib), Hib carriage was studied in children aged 6-24 months attending day care centers in two cities in southern Brazil (Curitiba and Porto Alegre), in Curitiba, routine immunization with Hib polyribosylribitol phosphate polysaccharide-tetanus toroid conjugate vaccine (PRP-T) in combination with diphtheria-tetanus toxoids-pertussis vaccine (PRP-T/DTP) has been offered since September 1996; DTP vaccine alone is routinely given in Porto Alegre, Children in Porto Alegre (n = 643) were 8 times less likely to have received adequate Hib vaccination and 4 times more likely to be Hib carriers than children in Curitiba (n = 647; i.e., point prevalence of oropharyngeal colonization, 4.8% vs. 1.2%). Point prevalence of carriage with non-type b or other nontypeable Hi was similar in children of both cities, There was a vaccination effect on carriage rates in children who received a primary 3-dose series, independent of the booster dose, suggesting that a booster may be unnecessary to induce population protection.Pasteur Merieux Connaught Brasil, Dept Med, BR-04552905 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Pediat, São Paulo, BrazilSecretaria Estado Saude São Paulo, Inst Adolfo Lutz, Seccao Bacteriol, São Paulo, BrazilSanta Casa Misericordia São Paulo, Fac Ciencias Med, Dept Patol, São Paulo, BrazilSecretaria Municipal Saude Curitiba, Dept Epidemiol, Curitiba, Parana, BrazilSecretaria Municipal Saude Porto Alegre, Dept Epidemiol, Porto Alegre, RS, BrazilUniversidade Federal de São Paulo, Dept Pediat, São Paulo, BrazilWeb of Scienc

Direct oral anticoagulants versus vitamin K antagonists in patients with atrial fibrillation and cancer a meta-analysis

Background: Direct oral anticoagulants (DOACs) are recommended as first-line anticoagulants in patients with atrial fibrillation (AF). However, in patients with cancer and AF the efficacy and safety of DOACs are not well established. Objective: We performed a meta-analysis comparing available data regarding the efficacy and safety of DOACs vs vitamin K antagonists (VKAs) in cancer patients with non-valvular AF. Methods: An online search of Pubmed and EMBASE libraries (from inception to May, 1 2020) was performed, in addition to manual screening. Nine studies were considered eligible for the meta-analysis involving 46,424 DOACs users and 182,797 VKA users. Results: The use of DOACs was associated with reduced risks of systemic embolism or any stroke (RR 0.65; 95% CI 0.52–0.81; p 0.001), ischemic stroke (RR 0.84; 95% CI 0.74–0.95; p 0.007) and hemorrhagic stroke (RR 0.61; 95% CI 0.52–0.71; p 0.00001) as compared to VKA group. DOAC use was associated with significantly reduced risks of major bleeding (RR 0.68; 95% CI 0.50–0.92; p 0.01) and intracranial or gastrointestinal bleeding (RR 0.64; 95% CI 0.47–0.88; p 0.006). Compared to VKA, DOACs provided a non-statistically significant risk reduction of the outcomes major bleeding or non-major clinically relevant bleeding (RR 0.94; 95% CI 0.78–1.13; p 0.50) and any bleeding (RR 0.91; 95% CI 0.78–1.06; p 0.24). Conclusions: In comparison to VKA, DOACs were associated with a significant reduction of the rates of thromboembolic events and major bleeding complications in patients with AF and cancer. Further studies are needed to confirm our results

Pro-inflammatory cytokines as emerging molecular determinants in cardiolaminopathies

Mutations in Lamin A/C gene (lmna) cause a wide spectrum of cardiolaminopathies strictly associated with significant deterioration of the electrical and contractile function of the heart. Despite the continuous flow of biomedical evidence, linking cardiac inflammation to heart remodelling in patients harbouring lmna mutations is puzzling. Therefore, we profiled 30 serum cytokines/chemokines in patients belonging to four different families carrying pathogenic lmna mutations segregating with cardiac phenotypes at different stages of severity (n = 19) and in healthy subjects (n = 11). Regardless lmna mutation subtype, high levels of circulating granulocyte colony-stimulating factor (G-CSF) and interleukin 6 (IL-6) were found in all affected patients’ sera. In addition, elevated levels of Interleukins (IL) IL-1Ra, IL-1β IL-4, IL-5 and IL-8 and the granulocyte-macrophage colony-stimulating factor (GM-CSF) were measured in a large subset of patients associated with more aggressive clinical manifestations. Finally, the expression of the pro-inflammatory 70 kDa heat shock protein (Hsp70) was significantly increased in serum exosomes of patients harbouring the lmna mutation associated with the more severe phenotype. Overall, the identification of patient subsets with overactive or dysregulated myocardial inflammatory responses could represent an innovative diagnostic, prognostic and therapeutic tool against Lamin A/C cardiomyopathies