Model-based analysis of the autonomic response to head-up tilt testing in Brugada syndrome

The etiology of Brugada syndrome (BS) is complex and multifactorial, making risk stratification in this population a major challenge. Since changes in the autonomic modulation of these patients are commonly related to arrhythmic events, we analyze in this work whether the response to head-up tilt (HUT) testing on this population may provide useful, complementary information for risk stratification. In order to perform this analysis, a coupled physiological model integrating the cardiac electrical activity, the cardiovascular system and the baroreceptors reflex control of the autonomic function, in response to HUT is proposed. A sensitivity analysis was performed, based on a screening method, evidencing the influence of cardiovascular parameters on blood pressure and of baroreflex regulation on heart rate. The most sensitive parameters have been identified on a set of 20 subjects (8 controls and 12 BS patients), so as to assess subject-specific model parameters. According to the results, controls showed an increased sympathetic modulation after tilting, as well as a reduced left ventricular contractility was observed in symptomatic, with respect to asymptomatic BS patients. These results provide new insights regarding the autonomic mechanisms regulating the cardiovascular system in BS which might be used as a complementary source of information, along with classical electrophysiological parameters, for BS risk stratification.Peer ReviewedPostprint (author's final draft

Natural ester fluids applications in transformers as a sustainable dielectric and coolant

New requirements for a better sustainable energy policy around the world is easy to observe, many projects in sustainable energy are developed wherein the academia works together the authorities and commercial firms such as electrical grid utilities. In distribution transformers one of the suggested solutions is to replace mineral oils used as dielectric and coolant for natural ester fluids, they provide improved technical properties making them a safe substitute of mineral oil. Natural esters are based on clean technology in order to guarantee requirements from utilities. The main goal of the present paper is to present a technical-economic analysis obtained from five years of applications of oil-immersed transformers using natural ester fluids in Colombia. The methodology considers forty-four oil-immersed distribution Transformers, a half use mineral oil and the other side use natural ester, operating under the same load regime. Results evidenced the feasibility of implementing this technology because the costs are very similar and the reduction of risks and environmental impact is considerable. © 2019 Author(s)

Natural inhibitors of pancreatic lipase as new players in obesity treatment

Obesity is a multifactorial disease characterized by an excessive weight for height due to an enlarged fat deposition such as adipose tissue, which is attributed to a higher calorie intake than the energy expenditure. The key strategy to combat obesity is to prevent chronic positive impairments in the energy equation. However, it is often difficult to maintain energy balance, because many available foods are high-energy yielding, which is usually accompanied by low levels of physical activity. The pharmaceutical industry has invested many efforts in producing antiobesity drugs; but only a lipid digestion inhibitor obtained from an actinobacterium is currently approved and authorized in Europe for obesity treatment. This compound inhibits the activity of pancreatic lipase, which is one of the enzymes involved in fat digestion. In a similar way, hundreds of extracts are currently being isolated from plants, fungi, algae, or bacteria and screened for their potential inhibition of pancreatic lipase activity. Among them, extracts isolated from common foodstuffs such as tea, soybean, ginseng, yerba mate, peanut, apple, or grapevine have been reported. Some of them are polyphenols and saponins with an inhibitory effect on pancreatic lipase activity, which could be applied in the management of the obesity epidemic

Classification de séries temporelles par modèles markoviens cachés, application à l'ischémie myocardique

A new method for myocardial ischemia detection is proposed in this communication. The originality of this method relies on the consideration of the dynamics of times series extracted from the ECG whereas traditionnal methods are simply based on static measures. After the extraction of a feature vector, the dynamics are caracterised with an Hidden Semi-Markovian Model (HSMM). The ischemic detector uses a reference HSMM and an ischemic HSMM and then compare the likelihood of the time series. Results obtained with PTCA (percutaneous transluminal coronary angioplasty) records of the STAFF3 database show a very good detection rate (96% of sensibility and 80% of specificity).Postprint (published version

Do the Effects of Resveratrol on Thermogenic and Oxidative Capacities in IBAT and Skeletal Muscle Depend on Feeding Conditions?

The aim of this study was to compare the effects of mild energy restriction and resveratrol on thermogenic and oxidative capacity in interscapular brown adipose tissue (IBAT) and in skeletal muscle. Rats were fed a high-fat high-sucrose diet for six weeks, and divided into four experimental groups fed a standard diet: a control group, a resveratrol-treated group, an energy-restricted group and an energy-restricted group treated with resveratrol. Weights of IBAT, gastrocnemius muscle and fat depots were measured. Activities of carnitine palmitoyltransferase (CPT) and citrate synthase (CS), protein levels of sirtuin (SIRT1 and 3), uncoupling proteins (UCP1 and 3), glucose transporter (GLUT4), mitochondrial transcription factor (TFAM), nuclear respiratory factor (NRF1), peroxisome proliferator-activated receptor (PPAR) and AMP activated protein kinase (AMPK) and peroxisome proliferator-activated receptor gamma coactivator (PGC1) activation were measured. No changes in IBAT and gastrocnemius weights were found. Energy-restriction, but not resveratrol, decreased the weights of adipose depots. In IBAT, resveratrol enhanced thermogenesis activating the SIRT1/PGC1/PPAR axis. Resveratrol also induced fatty acid oxidation and glucose uptake. These effects were similar when resveratrol was combined with energy restriction. In the case of gastrocnemius muscle, the effects were not as clear as in the case of IBAT. In this tissue, resveratrol increased oxidative capacity. The combination of resveratrol and energy restriction seemingly did not improve the effects induced by the polyphenol alone.This research was funded by MINECO (AGL-2015-65719-R-MINECO/FEDER, UE), University of the Basque Country (ELDUNANOTEK UFI11/32), Instituto de Salud Carlos III (CIBERobn) and Basque Government (IT-572-13). Inaki Milton-Laskibar is a recipient of a doctoral fellowship from the Gobierno Vasco

Involvement of autophagy in the beneficial effects of resveratrol in hepatic steatosis treatment. A comparison with energy restriction

Autophagy eliminates damaged cellular components. In the liver, it has been proposed that it mediates the breakdown of lipid droplets. This study aimed to compare the involvement of autophagy and the oxidative status in the effects of resveratrol and energy restriction as therapeutic tools for managing liver steatosis. In addition, potential additive or synergic effects were studied. Rats were fed a high-fat high-sucrose diet for 6 weeks and then divided into four experimental groups and fed a standard diet: a control group (C), a resveratrol-treated group (RSV, 30 mg kg−1 d−1), an energy restricted group (R, −15%), and an energy restricted group treated with resveratrol (RR). Liver triacylglycerols (TGs) were measured by Folch's method. TBARS, GSH, GSSG, GPx and SOD were assessed using commercial kits. The protein expression of beclin, atg5 and p62, as well as ratios of pSer555 ULK1/total ULK1, pSer757 ULK1/total ULK1 and LC3 II/I were determined by western blotting. Energy restriction increased the protein expression of beclin, atg5 and pSer757 ULK1/total ULK1 and LC3 II/I ratios, and reduced the protein expression of p62, thus indicating that it induced autophagy activation. The effects of resveratrol were similar but less marked than the hypocaloric diet. No differences were observed in oxidative stress determinants except for TBARS, which was decreased by energy restriction. In conclusion, resveratrol can reverse partially dietary-induced hepatic lipid accumulation, although less efficiently than energy restriction. The delipidating effect of energy restriction is mediated in part by the activation of autophagy; however, the involvement of this process in the effects of resveratrol is less clear

Combined Approach to Stroke Thrombectomy Using a Novel Short Flexible Aspiration Catheter with a Stent Retriever

Background: Large-bore aspiration catheters enabling greater flow rates and suction force for mechanical thrombectomy might improve outcomes in patients with stroke secondary to large-vessel occlusion. Complete or near-complete reperfusion after a single thrombectomy pass (first-pass effect) is associated with improved clinical outcomes. We assessed the efficacy and safety of novel MIVI Q™ aspiration catheters in combination with stent-retriever devices. Methods: We retrospectively analyzed demographics, procedure characteristics, and clinical data from consecutive patients with acute anterior large-vessel occlusion treated with a combined approach using MIVI Q™ aspiration catheters and stent retrievers. Reperfusion was defined according to the modified thrombolysis in cerebral infarction (mTICI) score. Clinical outcomes were measured by the National Institute of Health Stroke Scale (NIHSS) and modified Rankin scale (mRS) scores. Results: We included 52 patients (median age, 75 y IQR: 64-83); 31 (59.6%) women; 14 (26.9%) with terminal internal carotid artery occlusions, 26 (50%) middle cerebral artery (MCA) segment M1 occlusions, and 12 (23.1%) MCA segment M2 occlusions; median NIHSS score at admission was 19 (IQR: 13-22). After the first pass, 25 (48%) patients had mTICI ≥ 2c. At the end of the procedure, 47 (90.4%) had mTICI ≥ 2b and 35 (67.3%) had mTICI ≥ 2c. No serious device-related adverse events were observed. Symptomatic intracranial hemorrhage developed in 1 patient. Mean NIHSS score was 13 at 24 h and 5 at discharge. At 90 days, 24 (46.2%) patients were functionally independent (mRS 0-2). Conclusion: This preliminary study found good efficacy and safety for MIVI Q™ aspiration catheters used in combination with stent-retriever devices

Evaluation of Suitable Lands for Elaeis guineensis Jacq. Using Geographic Information Systems in the Sierra Region, Tabasco, Mexico

Objective: The objective was to evaluate the edaphic aptitude of Elaeis guineensis J. at a semi-detailed level (scale 1: 50000) in Plains and Terrazas de Tabasco (PTT). Design/methodology/approach: The edaphic requirements consisted of a semi-detailed soil map. The evaluation of the edaphic aptitude was based on the agroecological zoning methodology proposed by FAO, and the final 1: 50000 scale map was designed with the algebra mapping tool with the ArcGis Geographic Information System. Results: The Gleysols, Fluvisols, Luvisols and Lixisols groups dominate the PTT, with 65.1%, 16.2%, 6.3% and 4% respectively. 79.95% of the soils have zero aptitude towards oil palm. Limitations on study/implications: In the economy of the Mexican Southeast, oil palm is the eighth most important perennial crop above cocoa, in this scenario it is possible the expansion of plantations in the country, therefore, it is important to comply with internal regulations and carry. Findings/conclusions: The limiting factor to establish Elaeis guineensis plantations in the plains and terraces of Tabasco, Mexico, is the internal drainage of the Gleysols soils.Objective: The objective of this study was to evaluate the edaphic suitability of Elaeis guineensis at a semi-detailed scale (1:50000), in the Plains and Terraces of Tabasco, Mexico (PTT). Design/Methodology/Approach: The edaphic requirements consisted of a semi-detailed soil map. The evaluation of the edaphic suitability was based on the agroecological zoning methodology proposed by FAO and the final 1:50000 scale map was developed using the algebra mapping tool with the ArcGis® Geographic Information System. Results: The Gleysols, Fluvisols, Luvisols, and Lixisols groups dominate the PTT, with 65.1, 16.2, 6.3, and 4%, respectively. Most of the soils (79.95%) have zero suitability for oil palm. Study Limitations/Implications: Oil palm is the eighth most important perennial crop (over cocoa) for the economy of southeastern Mexico. In this scenario, the expansion of plantations in the country is a possibility; therefore, complying with internal regulations and carry is important. Findings/Conclusions: The internal drainage of Gleysols soils limits the establishment of E. guineensis plantations in the plains and terraces of Tabasco, Mexico