LANDMARK comparison of early outcomes of newer-generation Myval transcatheter heart valve series with contemporary valves (Sapien and Evolut) in real-world individuals with severe symptomatic native aortic stenosis: a randomised non-inferiority trial.

BACKGROUND: Transcatheter aortic valve implantation is an established, guideline-endorsed treatment for severe aortic stenosis. Precise sizing of the balloon-expandable Myval transcatheter heart valve (THV) series with the aortic annulus is facilitated by increasing its diameter in 1·5 mm increments, compared with the usual 3 mm increments in valve size. The LANDMARK trial aimed to show non-inferiority of the Myval THV series compared with the contemporary THVs Sapien Series (Edwards Lifesciences, Irvine, CA, USA) or Evolut Series (Medtronic, Minneapolis, MN, USA). METHODS: In this prospective, multinational, randomised, open-label, non-inferiority trial across 31 hospitals in 16 countries (Germany, France, Sweden, the Netherlands, Italy, Spain, New Zealand, Portugal, Greece, Hungary, Poland, Slovakia, Slovenia, Croatia, Estonia, and Brazil), 768 participants with severe symptomatic native aortic stenosis were randomly assigned (1:1) to the Myval THV or a contemporary THV. Eligibility was primarily decided by the heart team in accordance with 2021 European Society of Cardiology guidelines. As per the criteria of the third Valve Academic Research Consortium, the primary endpoint at 30 days was a composite of all-cause mortality, all stroke, bleeding (types 3 and 4), acute kidney injury (stages 2-4), major vascular complications, moderate or severe prosthetic valve regurgitation, and conduction system disturbances resulting in a permanent pacemaker implantation. Non-inferiority of the study device was tested in the intention-to-treat population using a non-inferiority margin of 10·44% and assuming an event rate of 26·10%. This trial is registered with ClinicalTrials.gov, NCT04275726, and EudraCT, 2020-000137-40, and is closed to new participants. FINDINGS: Between Jan 6, 2021, and Dec 5, 2023, 768 participants with severe symptomatic native aortic stenosis were randomly assigned, 384 to the Myval THV and 384 to a contemporary THV. 369 (48%) participants had their sex recorded as female, and 399 (52%) as male. The mean age of participants was 80·0 years (SD 5·7) for those treated with the Myval THV and 80·4 years (5·4) for those treated with a contemporary THV. Median Society of Thoracic Surgeons scores were the same in both groups (Myval 2·6% [IQR 1·7-4·0] vs contemporary 2·6% [1·7-4·0]). The primary endpoint showed non-inferiority of the Myval (25%) compared with contemporary THV (27%), with a risk difference of -2·3% (one-sided upper 95% CI 3·8, pnon-inferiority<0·0001). No significant difference was seen in individual components of the primary composite endpoint. INTERPRETATION: In individuals with severe symptomatic native aortic stenosis, the Myval THV met its primary endpoint at 30 days. FUNDING: Meril Life Sciences.

Direct Inhibition of BK Channels by Cannabidiol, One of the Principal Therapeutic Cannabinoids Derived from Cannabis sativa.

Cannabidiol (CBD), one of the main Cannabis sativa bioactive compounds, is utilized in the treatment of major epileptic syndromes. Its efficacy can be attributed to a multimodal mechanism of action that includes, as potential targets, several types of ion channels. In the brain, CBD reduces the firing frequency in rat hippocampal neurons, partly prolonging the duration of action potentials, suggesting a potential blockade of voltage-operated K+ channels. We postulate that this effect might involve the inhibition of the large-conductance voltage- and Ca2+-operated K+ channel (BK channel), which plays a role in the neuronal action potential's repolarization. Thus, we assessed the impact of CBD on the BK channel activity, heterologously expressed in HEK293 cells. Our findings, using the patch-clamp technique, revealed that CBD inhibits BK channel currents in a concentration-dependent manner with an IC50 of 280 nM. The inhibition is through a direct interaction, reducing both the unitary conductance and voltage-dependent activation of the channel. Additionally, the cannabinoid significantly delays channel activation kinetics, indicating stabilization of the closed state. These effects could explain the changes induced by CBD in action potential shape and duration, and they may contribute to the observed anticonvulsant activity of this cannabinoid.

Sympathetic nervous activation, mitochondrial dysfunction and outcome in acutely decompensated cirrhosis: the metabolomic prognostic models (CLIF-C MET).

BACKGROUND AND AIMS: Current prognostic scores of patients with acutely decompensated cirrhosis (AD), particularly those with acute-on-chronic liver failure (ACLF), underestimate the risk of mortality. This is probably because systemic inflammation (SI), the major driver of AD/ACLF, is not reflected in the scores. SI induces metabolic changes, which impair delivery of the necessary energy for the immune reaction. This investigation aimed to identify metabolites associated with short-term (28-day) death and to design metabolomic prognostic models. METHODS: Two prospective multicentre large cohorts from Europe for investigating ACLF and development of ACLF, CANONIC (discovery, n=831) and PREDICT (validation, n=851), were explored by untargeted serum metabolomics to identify and validate metabolites which could allow improved prognostic modelling. RESULTS: Three prognostic metabolites strongly associated with death were selected to build the models. 4-Hydroxy-3-methoxyphenylglycol sulfate is a norepinephrine derivative, which may be derived from the brainstem response to SI. Additionally, galacturonic acid and hexanoylcarnitine are associated with mitochondrial dysfunction. Model 1 included only these three prognostic metabolites and age. Model 2 was built around 4-hydroxy-3-methoxyphenylglycol sulfate, hexanoylcarnitine, bilirubin, international normalised ratio (INR) and age. In the discovery cohort, both models were more accurate in predicting death within 7, 14 and 28 days after admission compared with MELDNa score (C-index: 0.9267, 0.9002 and 0.8424, and 0.9369, 0.9206 and 0.8529, with model 1 and model 2, respectively). Similar results were found in the validation cohort (C-index: 0.940, 0.834 and 0.791, and 0.947, 0.857 and 0.810, with model 1 and model 2, respectively). Also, in ACLF, model 1 and model 2 outperformed MELDNa 7, 14 and 28 days after admission for prediction of mortality. CONCLUSIONS: Models including metabolites (CLIF-C MET) reflecting SI, mitochondrial dysfunction and sympathetic system activation are better predictors of short-term mortality than scores based only on organ dysfunction (eg, MELDNa), especially in patients with ACLF.

A Combined Ligand- and Structure-Based Virtual Screening To Identify Novel NaV1.2 Blockers: In Vitro Patch Clamp Validation and In Vivo Anticonvulsant Activity.

Epilepsy is a neurological disorder characterized by recurrent seizures that arise from abnormal electrical activity in the brain. Voltage-gated sodium channels (NaVs), responsible for the initiation and propagation of action potentials in neurons, play a critical role in the pathogenesis of epilepsy. This study sought to discover potential anticonvulsant compounds that interact with NaVs, specifically, the brain subtype hNaV1.2. A ligand-based QSAR model and a docking model were constructed, validated, and applied in a parallel virtual screening over the DrugBank database. Montelukast, Novobiocin, and Cinnarizine were selected for in vitro testing, using the patch-clamp technique, and all of them proved to inhibit hNaV1.2 channels heterologously expressed in HEK293 cells. Two hits were evaluated in the GASH/Sal model of audiogenic seizures and demonstrated promising activity, reducing the severity of sound-induced seizures at the doses tested. The combination of ligand- and structure-based models presents a valuable approach for identifying potential NaV inhibitors. These findings may provide a basis for further research into the development of new antiseizure drugs for the treatment of epilepsy.

Amphilimus- vs. zotarolimus-eluting stents in patients with diabetes mellitus and coronary artery disease: the SUGAR trial.

AIM: Patients with diabetes mellitus are at high risk of adverse events after percutaneous revascularization, with no differences in outcomes between most contemporary drug-eluting stents. The Cre8 EVO stent releases a formulation of sirolimus with an amphiphilic carrier from laser-dug wells, and has shown clinical benefits in diabetes. We aimed to compare Cre8 EVO stents to Resolute Onyx stents (a contemporary polymer-based zotarolimus-eluting stent) in patients with diabetes. METHODS AND RESULTS: We did an investigator-initiated, randomized, controlled, assessor-blinded trial at 23 sites in Spain. Eligible patients had diabetes and required percutaneous coronary intervention. A total of 1175 patients were randomly assigned (1:1) to receive Cre8 EVO or Resolute Onyx stents. The primary endpoint was target-lesion failure, defined as a composite of cardiac death, target-vessel myocardial infarction, and clinically indicated target-lesion revascularization at 1-year follow-up. The trial had a non-inferiority design with a 4% margin for the primary endpoint. A superiority analysis was planned if non-inferiority was confirmed. There were 106 primary events, 42 (7.2%) in the Cre8 EVO group and 64 (10.9%) in the Resolute Onyx group [hazard ratio (HR): 0.65, 95% confidence interval (CI): 0.44-0.96; Pnon-inferiority < 0.001; Psuperiority = 0.030]. Among the secondary endpoints, Cre8 EVO stents had significantly lower rate than Resolute Onyx stents of target-vessel failure (7.5% vs. 11.1%, HR: 0.67, 95% CI: 0.46-0.99; P = 0.042). Probable or definite stent thrombosis and all-cause death were not significantly different between groups. CONCLUSION: In patients with diabetes, Cre8 EVO stents were non-inferior to Resolute Onyx stents with regard to target-lesion failure composite outcome. An exploratory analysis for superiority at 1 year suggests that the Cre8 EVO stents might be superior to Resolute Onyx stents with regard to the same outcome. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov: NCT03321032.

Upper gastrointestinal bleeding and Rigler triad.

Gallstone ileus is a rare complication of cholelithiasis, characterized by mechanical bowel obstruction due to a biliary calculus originating from a bilioenteric fistula. The Rigler triad, consisting of aerobilia, ectopic gallstone, and intestinal obstruction, is rarely observed in its complete form. We present the case of a 92-year-old male with a history of acute lithiasic cholecystitis who presented to the Emergency department with acute epigastric pain. Initial evaluation revealed gallbladder dilatation, gallstones, and gallbladder wall thickening suggestive of acute cholecystitis. During hospitalization, the patient experienced an episode of hematemesis, leading to the diagnosis of a cholecystoduodenal fistula and a large blood clot in the duodenal bulb. Further imaging showed an ectopic gallstone causing small bowel obstruction. The patient underwent urgent surgery for stone extraction, followed by endoscopic intervention for the bleeding vessel identified at a subsequent gastroscopy. Unfortunately, the patient had a poor postoperative course and passed away seven days later. This case report highlights the exceptional occurrence of both the Rigler triad and upper gastrointestinal bleeding in a patient with gallstone ileus. Surgical intervention is crucial for the initial resolution of intestinal obstruction, followed by cholecystectomy and repair of the bilioenteric fistula. Awareness of these rare presentations is important for timely diagnosis and appropriate management of this uncommon complication of cholelithiasis.

Next-generation balloon-expandable Myval transcatheter heart valve in low-risk aortic stenosis patients.

OBJECTIVES: We aimed to describe hemodynamic performance and clinical outcomes at 30-day follow-up of the balloon-expandable (BE) Myval transcatheter heart valve (THV) in low-risk patients. BACKGROUND: The results of the next-generation BE Myval THV in low-risk aortic stenosis (AS) patients are still unknown. METHODS: Retrospective registry performed in nine European centers including patients with low predicted operative mortality risk according to Society of thoracic surgeons (STS) and European system for cardiac operative risk evaluation (EuroSCORE-II) scores. RESULTS: Between September 2019 and February 2021, a total of 100 patients (51% males, mean age 80 ± 6.5 years) were included. Mean STS score and EuroSCORE-II were 2.4 ± 0.8% and 2.2 ± 0.7%, respectively. Intermediate sizes were used in 39% (21.5 mm: 8%, 24.5 mm: 15%, 27.5 mm: 15%). There were no cases of valve embolization, coronary artery occlusion, annulus rupture, or procedural death. A definitive pacemaker implantation was needed in eight patients (8%). At 30-day follow-up aortic valve area (0.7 ± 0.2 vs. 2.1 ± 0.6 cm2 ) and mean aortic valve gradient (43.4 ± 11.1 vs. 9.0 ± 3.7 mmHg) improved significantly (p < 0.001). Moderate aortic regurgitation occurred in 4%. Endpoints of early safety and clinical efficacy were 3 and 1%, respectively. CONCLUSIONS: Hemodynamic performance and 30-day clinical outcomes of the BE Myval THV in low-risk AS patients were favorable. Longer-term follow-up is warranted.

A bacteraemia risk prediction model: development and validation in an emergency medicine population.

OBJECTIVE: Design a risk model to predict bacteraemia in patients attended in emergency departments (ED) for an episode of infection. METHODS: This was a national, prospective, multicentre, observational cohort study of blood cultures (BC) collected from adult patients (≥ 18 years) attended in 71 Spanish EDs from October 1 2019 to March 31, 2020. Variables with a p value < 0.05 were introduced in the univariate analysis together with those of clinical significance. The final selection of variables for the scoring scale was made by logistic regression with selection by introduction. The results obtained were internally validated by dividing the sample in a derivation and a validation cohort. RESULTS: A total of 4,439 infectious episodes were included. Of these, 899 (20.25%) were considered as true bacteraemia. A predictive model for bacteraemia was defined with seven variables according to the Bacteraemia Prediction Model of the INFURG-SEMES group (MPB-INFURG-SEMES). The model achieved an area under the curve-receiver operating curve of 0.924 (CI 95%:0.914-0.934) in the derivation cohort, and 0.926 (CI 95%: 0.910-0.942) in the validation cohort. Patients were then split into ten risk categories, and had the following rates of risk: 0.2%(0 points), 0.4%(1 point), 0.9%(2 points), 1.8%(3 points), 4.7%(4 points), 19.1% (5 points), 39.1% (6 points), 56.8% (7 points), 71.1% (8 points), 82.7% (9 points) and 90.1% (10 points). Findings were similar in the validation cohort. The cut-off point of five points provided the best precision with a sensitivity of 95.94%, specificity of 76.28%, positive predictive value of 53.63% and negative predictive value of 98.50%. CONCLUSION: The MPB-INFURG-SEMES model may be useful for the stratification of risk of bacteraemia in adult patients with infection in EDs, together with clinical judgement and other variables independent of the process and the patient.

Structure-Based Virtual Screening Identifies Novobiocin, Montelukast, and Cinnarizine as TRPV1 Modulators with Anticonvulsant Activity In Vivo.

The transient receptor potential vanilloid 1 (TRPV1) receptor is a nonselective cation channel, known to be involved in the regulation of many important physiological and pathological processes. In the last few years, it has been proposed as a promising target to develop novel anticonvulsant compounds. However, thermoregulatory effects associated with the channel inhibition have hampered the path for TRPV1 antagonists to become marketed drugs. In this regard, we conducted a structure-based virtual screening campaign to find potential TRPV1 modulators among approved drugs, which are known to be safe and thermally neutral. To this end, different docking models were developed and validated by assessing their pose and score prediction powers. Novobiocin, montelukast, and cinnarizine were selected from the screening as promising candidates for experimental testing and all of them exhibited nanomolar inhibitory activity. Moreover, the in vivo profiles showed promising results in at least one of the three models of seizures tested.

Novel Dimeric hHv1 Model and Structural Bioinformatic Analysis Reveal an ATP-Binding Site Resulting in a Channel Activating Effect.

The human voltage-gated proton channel (hHv1) is a highly selective ion channel codified by the HVCN1 gene. It plays a fundamental role in several physiological processes such as innate and adaptive immunity, insulin secretion, and sperm capacitation. Moreover, in humans, a higher hHv1 expression/function has been reported in several types of cancer cells. Here we report a multitemplate homology model of the hHv1 channel, built and refined as a dimer in Rosetta. The model was then subjected to extensive Gaussian accelerated molecular dynamics (GaMD) for enhanced conformational sampling, and representative snapshots were extracted by clustering analysis. Combining different structure- and sequence-based methodologies, we predicted a putative ATP-binding site located on the intracellular portion of the channel. Furthermore, GaMD simulations of the ATP-bound dimeric hHv1 model showed that ATP interacts with a cluster of positively charged residues from the cytoplasmic N and C terminal segments. According to the in silico predictions, we found that 3 mM intracellular ATP significantly increases the H+ current mediated by the hHv1 channel expressed in HEK293 cells and measured by the patch-clamp technique in an inside-out configuration (2.86 ± 0.63 fold over control at +40 mV). When ATP was added on the extracellular side, it was not able to activate the channel supporting the idea that the ATP-binding site resides in the intracellular face of the hHV1 channel. In a physiological and pathophysiological context, this ATP-mediated modulation could integrate the cell metabolic state with the H+ efflux, especially in cells where hHv1 channels are relevant for pH regulation, such as pancreatic ß-cells, immune cells, and cancer cells.

Surprises in cecal intubation: foreign bodies in the colon.

We report the case of a 70-year-old male who visited for a colonoscopy on an outpatient basis after being admitted months earlier due to a subocclusive condition that was resolved with conservative treatment. His medical background included a laparotomy for a duodenal ulcer in 1979, as well as a subsequent intervention to debride adhesions. Cecal intubation was achieved with difficulty due to the patient's adhesive syndrome.

Large bowel obstruction secondary to a simple renal cyst: an exceptional complication.

We report the case of an 81-year-old female with large bowel obstruction secondary to a giant simple renal cyst (16 cm), which was producing a compression of the descending colon against the abdominal wall. Percutaneous drainage of the renal cyst was performed by a urologist. The follow-up CT scan revealed a collapsed cyst with resolution of the bowel obstruction. The patient showed resolution of the symptoms with an improvement in blood test results.

McKittrick-Wheelock syndrome: rectal villous adenoma as a cause of acute renal failure.

We report the case of a 67-year-old male with a history of arterial hypertension and atrial fibrillation, who was admitted for acute renal failure (creatinine: 4.41 mg/dl) and hypotension. He also presented hyponatremia (129 mmol/L) and hypokalemia (2.7 mmol/L). The patient referred profuse diarrhea during the previous two months as a possible triggering cause. Physical examination showed signs of dehydration and palpation of a polypoid mass in the rectal ampulla.

Intra-Day Solar Power Forecasting Strategy for Managing Virtual Power Plants.

Solar energy penetration has been on the rise worldwide during the past decade, attracting a growing interest in solar power forecasting over short time horizons. The increasing integration of these resources without accurate power forecasts hinders the grid operation and discourages the use of this renewable resource. To overcome this problem, Virtual Power Plants (VPPs) provide a solution to centralize the management of several installations to minimize the forecasting error. This paper introduces a method to efficiently produce intra-day accurate Photovoltaic (PV) power forecasts at different locations, by using free and available information. Prediction intervals, which are based on the Mean Absolute Error (MAE), account for the forecast uncertainty which provides additional information about the VPP node power generation. The performance of the forecasting strategy has been verified against the power generated by a real PV installation, and a set of ground-based meteorological stations in geographical proximity have been used to emulate a VPP. The forecasting approach is based on a Long Short-Term Memory (LSTM) network and shows similar errors to those obtained with other deep learning methods published in the literature, offering a MAE performance of 44.19 W/m2 under different lead times and launch times. By applying this technique to 8 VPP nodes, the global error is reduced by 12.37% in terms of the MAE, showing huge potential in this environment.

Turning Base Transceiver Stations into Scalable and Controllable DC Microgrids Based on a Smart Sensing Strategy.

This paper describes a practical approach to the transformation of Base Transceiver Stations (BTSs) into scalable and controllable DC Microgrids in which an energy management system (EMS) is developed to maximize the economic benefit. The EMS strategy focuses on efficiently managing a Battery Energy Storage System (BESS) along with photovoltaic (PV) energy generation, and non-critical load-shedding. The EMS collects data such as real-time energy consumption and generation, and environmental parameters such as temperature, wind speed and irradiance, using a smart sensing strategy whereby measurements can be recorded and computing can be performed both locally and in the cloud. Within the Spanish electricity market and applying a two-tariff pricing, annual savings per installed battery power of 16.8 euros/kW are achieved. The system has the advantage that it can be applied to both new and existing installations, providing a two-way connection to the electricity grid, PV generation, smart measurement systems and the necessary management software. All these functions are integrated in a flexible and low cost HW/SW architecture. Finally, the whole system is validated through real tests carried out on a pilot plant and under different weather conditions.

Novice nurse's transitioning to emergency nurse during COVID-19 pandemic: A qualitative study.

AIM: To explore the experiences and perceptions of recent nursing graduates working in emergency departments during the COVID-19 outbreak. BACKGROUND: Overcrowding in emergency departments has been one of the most prominent issues arising in these units for more than 20 years. However, it has become even more problematic due to the novelty of the coronavirus pandemic, which has forced hospitals to recruit larger numbers of beginner nursing staff as the number of quarantined health professionals increases. METHODS: Sixteen semi-structured interviews were conducted in Spanish emergency departments, which were analysed and synthesized using content analysis. RESULTS: Three major themes emerged from the data analysis: (a) Fears and concerns, (b) Organisational issues and (c) Support for novice nurses. CONCLUSIONS: Our findings may help to understand how shadowing periods as a learning programme for nurses, continuing professional development, evidence-based apps and better planning are needed to ensure both novice nurses' confidence in emergency departments and expert emergency room nurses' ability to cope with complications in critical situations. IMPLICATIONS FOR NURSING MANAGEMENT: Training periods that include shadowing expert emergency room nurses, along with evidence-based technology, provide an opportunity to support novice nurses' transition into the workplace. These measures would provide a safety net and would increase novice nurses' confidence as well as high-quality care.

Differential expression of the long and truncated Hv1 isoforms in breast-cancer cells.

Metabolic reprogramming of cancer cells results in a high production of acidic substances that must be extruded to maintain tumor-cell viability. The voltage-gated proton channel (Hv1) mediates highly selective effluxes of hydronium-ion (H+ ) that prevent deleterious cytoplasmic acidification. In the work described here, we demonstrated for the first time that the amino-terminal-truncated isoform of Hv1 is more highly expressed in tumorigenic breast-cancer-cell lines than in nontumorigenic breast cells. With respect to Hv1 function, we observed that pharmacologic inhibition of that channel, mediated by the specific blocker 5-chloro-2-guanidinobenzimidazole, produced a drop in intracellular pH and a decrease in cell viability, both in monolayer and in three-dimensional cultures, and adversely affected the cell-cycle in tumorigenic breast cells without altering the cycling of nontumorigenic cells. In conclusion, our results demonstrated that the Hv1 channel could be a potential tool both as a biomarker and as a therapeutic target in breast-cancer disease.

Relationships between chlorophyll content of vine leaves, predawn leaf water potential at veraison, and chemical and sensory attributes of wine.

BACKGROUND: Water deficit and iron deficiency (iron chlorosis) are common environmental stresses that affect grapevine production in the Mediterranean area. Studies on the impact of both stresses, when they act simultaneously, are rare. The main objective of this investigation was to evaluate the combined effects of the incidence of iron chlorosis and the vine water status on quality of Tempranillo wine. For this, 20 non-irrigated vineyard subzones (10 m × 10 m each), from non-affected to moderately affected by iron chlorosis, were monitored in the Ribera del Duero area (north-central Spain) during two consecutive seasons. RESULTS: Factorial analyses of variance were performed to study the effects of predawn leaf water potential and foliar chlorophyll content, both measured at veraison, on chemical and sensory characteristics of wine. With an impact much greater than water status, the incidence of iron stress decreased pH of the wine and enhanced sensory attributes as tonality, layer intensity, flavour intensity, and persistence in the mouth. There were increases in red colour, astringency, and persistence of the wine associated with chlorosis, although they might be restricted in water-deficit conditions. CONCLUSION: The results have demonstrated that mild to moderate iron stress can have positive effects on chemical and sensory attributes of Tempranillo wine. Measurements of foliar chlorophyll content at veraison could be very useful to map quality potential in rainfed vineyards affected by iron deficiency. © 2020 Society of Chemical Industry.

Design, synthesis and biological evaluation of N-substituted α-hydroxyimides and 1,2,3-oxathiazolidine-4-one-2,2-dioxides with anticonvulsant activity.

In this investigation, we studied a family of compounds with an oxathiazolidine-4-one-2,2-dioxide skeleton and their amide synthetic precursors as new anticonvulsant drugs. The cyclic structures were synthesized using a three-step protocol that include solvent-free reactions and microwave-assisted heating. The compounds were tested in vivo through maximal electroshock seizure test in mice. All the structures showed activity at the lower doses tested (30 mg/Kg) and no signs of neurotoxicity were detected. Compound encoded as 1g displayed strong anticonvulsant effects in comparison with known anticonvulsants (ED50 = 29 mg/Kg). First approximations about the mechanisms of action of the cyclic structures were proposed by docking simulations and in vitro assays against sodium channels (patch clamp methods).

Searching for New Leads To Treat Epilepsy: Target-Based Virtual Screening for the Discovery of Anticonvulsant Agents.

The purpose of this investigation is to contribute to the development of new anticonvulsant drugs to treat patients with refractory epilepsy. We applied a virtual screening protocol that involved the search into molecular databases of new compounds and known drugs to find small molecules that interact with the open conformation of the Nav1.2 pore. As the 3D structure of human Nav1.2 is not available, we first assembled 3D models of the target, in closed and open conformations. After the virtual screening, the resulting candidates were submitted to a second virtual filter, to find compounds with better chances of being effective for the treatment of P-glycoprotein (P-gp) mediated resistant epilepsy. Again, we built a model of the 3D structure of human P-gp, and we validated the docking methodology selected to propose the best candidates, which were experimentally tested on Nav1.2 channels by patch clamp techniques and in vivo by the maximal electroshock seizure (MES) test. Patch clamp studies allowed us to corroborate that our candidates, drugs used for the treatment of other pathologies like Ciprofloxacin, Losartan, and Valsartan, exhibit inhibitory effects on Nav1.2 channel activity. Additionally, a compound synthesized in our lab, N, N'-diphenethylsulfamide, interacts with the target and also triggers significant Na1.2 channel inhibitory action. Finally, in vivo studies confirmed the anticonvulsant action of Valsartan, Ciprofloxacin, and N, N'-diphenethylsulfamide.