Transcranial direct current stimulation improves the QT variability index and autonomic cardiac control in healthy subjects older than 60 years

Background: Noninvasive brain stimulation technique is an interesting tool to investigate the causal relation between cortical functioning and autonomic nervous system (ANS) responses. Objective: The objective of this report is to evaluate whether anodal transcranial direct current stimulation (tDCS) over the temporal cortex influences short-period temporal ventricular repolarization dispersion and cardiovascular ANS control in elderly subjects. Subjects and methods: In 50 healthy subjects (29 subjects younger than 60 years and 21 subjects older than 60 years) matched for gender, short-period RR and systolic blood pressure spectral variability, QT variability index (QTVI), and noninvasive hemodynamic data were obtained during anodal tDCS or sham stimulation. Results: In the older group, the QTVI, low-frequency (LF) power expressed in normalized units, the ratio between LF and high-frequency (HF) power, and systemic peripheral resistances decreased, whereas HF power expressed in normalized units and α HF power increased during the active compared to the sham condition (P,0.05). Conclusion: In healthy subjects older than 60 years, tDCS elicits cardiovascular and autonomic changes. Particularly, it improves temporal ventricular repolarization dispersion, reduces sinus sympathetic activity and systemic peripheral resistance, and increases vagal sinus activity and baroreflex sensitivity

Kinetics of Lipid Oxidation in Ternary Mixtures of Grape, Sesame and Sunflower Oils by Rancimat Method

O óleo extraído das sementes de uva é um produto com excelentes características antioxidantes e nutricionais, que pode ser utilizado na indústria de alimentos. Devido a essas características, este óleo foi incorporado, juntamente com o óleo de gergelim, em diferentes proporções, ao óleo de girassol, mantido na proporção de 50% em todas as misturas. Os óleos puros e misturas foram avaliados quanto à estabilidade termo-oxidativa (índice de estabilidade do óleo, OSI), compostos fenólicos, DPPH, cromatografia em fase gasosa, cinética de oxidação, entalpia e entropia e prazo de validade (a 25 ° C). A equação de Arrhenius e a teoria do complexo ativado foram utilizadas para estimar as energias de ativação, entalpias e entropia de ativação, variando de 80,66 a 90,37 kJ / mol, 77,84 a 86,61 kJ / mol e -129,46 a -104,37 J / mol K, respectivamente. O óleo de uva puro e as misturas com a maior proporção destes adicionados (B1 e B2) apresentaram os melhores valores em todos os parâmetros analisados. Os valores de energia livre de ativação (ΔG), que variaram de 27,68 a 38,59 kJ / mol, unificaram e verificaram os resultados dos outros parâmetros cinéticos, que indicam uma menor taxa de oxidação lipídica para a mistura B1, com maior proporção de uvas adicionadas

time and frequency domain analysis of beat to beat p wave duration pr interval and rr interval can predict asystole as form of syncope during head up tilt

To seek possible differences in short-period temporal RR interval, P-wave and PR interval dispersion and spectral coherence in patients with a head-up tilt test positive for vasovagal syncope with or without prolonged asystole, severe symptoms and at high risk of trauma. We retrospectively reviewed 5 min ECG and blood pressure recordings obtained at baseline, at rest and during head-up tilt in 40 patients diagnosed as having recurrent vasovagal syncope confirmed at a head-up tilt test. We analysed autoregressive spectral power for all the ECG-derived variables, focusing on temporal P-wave and PR interval dispersion indexes as well as their spectral coherence calculated on the same 5 min recordings at rest and during tilt. ECG recordings obtained during tilt before syncope showed significantly lower P → PR spectral coherence and higher RR standard deviations in patients with tilt-induced asystole than in those without (0.567 ± 0.097 versus 0.670 ± 0.127, p: 0.010 and 84 ± 36 versus 46 ± 22 ms2, p < 0.0001). Differences in the RR standard deviations persisted also on the last hundred beats (−100) (113 ± 54 versus 34 ± 17 ms2, p < 0.0001). Multiple regression analysis identified a significantly negative association between the maximum RR intervals and P → PR coherence at rest (β: −0.3, p < 0.05) and positive association with RR−100 standard deviation during tilt-induced syncope (β: 0.621, p < 0.001). P → PR spectral coherence could be used to assess the risk of prolonged asystole in patients with tilt-induced vasovagal syncope as well as as a possible surrogate for tilt-testing during these patients' follow-up

Oscillatory behavior of P wave duration and PR interval in experimental congestive heart failure: a preliminary study

Objective: The relationship between the autonomic nervous system (ANS) modulation of the sinus node and heart rate variability has been extensively investigated. The current study sought to evaluate, in an animal experimental model of pacing-induced tachycardia congestive heart failure (CHF), a possible ANS influence on the P wave duration and PR interval oscillations. Approach: Short-term (5 min) time and frequency domain analysis has been obtained in six dogs for the following electrocardiographic intervals: P wave duration (P), from the onset to peak of P wave (P p), from the onset of P wave to the q onset (PR) and from the end of P wave to the onset of q wave (P e R). Direct vagal nerve activity (VNA), stellate ganglion nerve activity (SGNA) and electrocardiogram (ECG) intervals have been evaluated contextually by implantation of three bipolar recording leads. Main results: At the baseline, multiple regression analysis pointed out that VNA was strongly positively associated with the standard deviation of PP and P e R intervals (r 2:0.997, p < 0.05). The same variable was also positively associated with high-frequency (HF) of P expressed in normalized units, of P p, and of P e R (b: 0.001) (r 2: 0.993; p < 0.05). During CHF, most of the time and frequency domain variability significantly decreased from 20% to 50% in comparison to the baseline values (p < 0.05) and SGNA correlated inversely with the low frequency (LF) obtained from P e R (p < 0.05) and PR (p < 0.05) (r 2:0.899, p < 0.05). LF components, expressed in absolute and normalized power, obtained from all studied intervals, were reduced significantly during CHF. Any difference between the RR and PP spectral components was observed. Significance: The data showed a significant relationship between ANS and atrial ECG variables, independent of the cycle duration. In particular, the oscillations were vagal mediated at the baseline, while sympathetic mediated during CHF. Whereas P wave variability might have a clinical utility in CHF management, it needs to be addressed in specific studies

GLAST Large Area Telescope simulation tools

This paper presents the simulation of the GLAST high energy gamma-ray telescope. The simulation package, written in C++, is based on the Geant4 toolkit, and it is integrated into a general framework used to process events. A detailed simulation of the electronic signals inside silicon detectors has been provided and it is used for the particle tracking, which is handled by a dedicated software. A unique repository for the geometrical description of the detector has been realized using the XML language and a C++ library to access this information has been designed and implemented. A new event display based on the HepRep protocol is being implemented. The GLAST satellite parameters derived from the simulation are used in a fast simulator to obtain a "snapshot" of the gamma-ray sky. This paper outlines the contribution developed by the Italian GLAST software group

EVALITA Evaluation of NLP and Speech Tools for Italian - December 17th, 2020

Welcome to EVALITA 2020! EVALITA is the evaluation campaign of Natural Language Processing and Speech Tools for Italian. EVALITA is an initiative of the Italian Association for Computational Linguistics (AILC, http://www.ai-lc.it) and it is endorsed by the Italian Association for Artificial Intelligence (AIxIA, http://www.aixia.it) and the Italian Association for Speech Sciences (AISV, http://www.aisv.it)

Inspection on bile acid scaffold in the discovery of the first example of LXR/GPBAR1 dual agonists

Hyodeoxycholic acid (HDCA), also known as 3α,6α-dihydroxy-5β-cholan-24-oic acid, is a secondary hydrophilic bile acid formed in human small intestine by bacterial C-6 hydroxylation of lithocholic acid. BAs are signaling molecules that activate at least four members of the nuclear receptors (NRs) superfamily: the farnesoid X receptor (FXR, NR1H4), identified as the endogenous bile acid sensor, the constitutive androstane receptor (CAR, NR1I3), the pregnane X receptor (PXR, NR1I2), the liver X receptor and the vitamin D receptor (VDR, NR1I1). In addition, secondary BAs activate G protein-coupled receptors (GPCRs), including GPBAR1 (also known as M-BAR, TGR5 or BG37). Several studies affirmed the therapeutical potential of HDCA administration in various metabolic disorders. HDCA has been shown to prevent gallstone formation, to reduce the levels of cholesterol in the liver and in the plasma suggesting its beneficial effects in the treatment of increased plasma cholesterol levels and atherosclerosis. In this communication, we report a novel library of semisynthetic bile acid derivatives obtained by modifications on the HDCA scaffold. The pharmacological characterization of this library led to the discovery of the first examples of novel dual ligands for LXR and GP-BAR1 receptors that might hold utility in the treatment of several metabolic disorders such as obesity and atherosclerosi

Time- and frequency-domain analysis of beat to beat P-wave duration, PR interval and RR interval can predict asystole as form of syncope during head-up tilt

To seek possible differences in short-period temporal RR interval, P-wave and PR interval dispersion and spectral coherence in patients with a head-up tilt test positive for vasovagal syncope with or without prolonged asystole, severe symptoms and at high risk of trauma. We retrospectively reviewed 5 min ECG and blood pressure recordings obtained at baseline, at rest and during head-up tilt in 40 patients diagnosed as having recurrent vasovagal syncope confirmed at a head-up tilt test. We analysed autoregressive spectral power for all the ECG-derived variables, focusing on temporal P-wave and PR interval dispersion indexes as well as their spectral coherence calculated on the same 5 min recordings at rest and during tilt. ECG recordings obtained during tilt before syncope showed significantly lower P → PR spectral coherence and higher RR standard deviations in patients with tilt-induced asystole than in those without (0.567 ± 0.097 versus 0.670 ± 0.127, p: 0.010 and 84 ± 36 versus 46 ± 22 ms2, p &lt; 0.0001). Differences in the RR standard deviations persisted also on the last hundred beats (-100) (113 ± 54 versus 34 ± 17 ms2, p &lt; 0.0001). Multiple regression analysis identified a significantly negative association between the maximum RR intervals and P → PR coherence at rest (β: -0.3, p &lt; 0.05) and positive association with RR-100 standard deviation during tilt-induced syncope (β: 0.621, p &lt; 0.001). P → PR spectral coherence could be used to assess the risk of prolonged asystole in patients with tilt-induced vasovagal syncope as well as as a possible surrogate for tilt-testing during these patients' follow-up

Computational drug repurposing for the identification of SARS-CoV-2 main protease inhibitors

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the virus responsible for the known COVID-19 disease. Since currently no definitive therapies or vaccines for the SARS-CoV-2 virus are avail- able, there is an urgent need to identify effective drugs against SARS-CoV-2 infection. One of the best- known targets available is the main protease of this virus, crucial for the processing of polyproteins codified by viral RNA. In this work, we used a computational virtual screening procedure for the repur- posing of commercial drugs available in the DrugBank database as inhibitors of the SARS-CoV-2 main protease. Molecular docking calculations and molecular dynamics (MD) simulations have been applied. The computational model was validated through a self-docking procedure. The screening procedure highlighted five interesting drugs that showed a comparable or higher docking score compared to the crystallographic compound and maintained the protein binding during the MD runs. Amongst these drugs, Ritonavir has been used in clinical trials with patients affected by COVID-19 and Nelfinavir showed anti-SARS-CoV-2 activity. The five identified drugs could be evaluated experimentally as inhibi- tors of the SARS-CoV-2 main protease in view of a possible COVID-19 treatment

Towards FXR selectivity: manipulation of 6-ethylcholane scaffold

Bile acids, the end-products of cholesterol catabolism, are signaling molecules activating several cellular networks through the recognition of nuclear and membrane receptors, such as the farnesoid-x-receptor (FXR) and a G-proteins coupled receptor (GP-BAR1). BAs are generated in the liver as primary bile acids, cholic acid (CA) and chenodeoxycholic acid (CDCA), conjugated with glycine and taurine, and then secreted in the small intestine and transformed by the intestinal microbiota into secondary bile acids, deoxycholic acid (DCA) and lithocholic acid (LCA). CDCA is the endogenous agonist of FXR while LCA and its corresponding tauro- and glyco-conjugates (GLCA and TLCA) are the most potent natural agonists for GP-BAR1. The main physiological role of FXR is the regulation of bile acids absorption, synthesis and secretion in the intestine, liver and kidney and it is considered a promising target in cholestasis. Although, GP-BAR1 agonists represent a novel opportunity in the treatment of entero-hepatic and metabolic disorders, a recent study has provided evidence that this receptor is the physiologic mediator of pruritus, a common symptom observed in cholestasis. In this contest, we have manipulated the bile acids scaffolds to obtain potent and selective FXR agonist