Cardiac-Specific Deletion of Scn8a Mitigates Dravet Syndrome-Associated Sudden Death in Adults.

BACKGROUND: Sudden unexpected death in epilepsy (SUDEP) is a fatal complication experienced by otherwise healthy epilepsy patients. Dravet syndrome (DS) is an inherited epileptic disorder resulting from loss of function of the voltage-gated sodium channel, NaV 1.1, and is associated with particularly high SUDEP risk. Evidence is mounting that NaVs abundant in the brain also occur in the heart, suggesting that the very molecular mechanisms underlying epilepsy could also precipitate cardiac arrhythmias and sudden death. Despite marked reduction of NaV 1.1 functional expression in DS, pathogenic late sodium current (INa,L) is paradoxically increased in DS hearts. However, the mechanisms by which DS directly impacts the heart to promote sudden death remain unclear. OBJECTIVES: In this study, the authors sought to provide evidence implicating remodeling of Na+ - and Ca2+ -handling machinery, including NaV 1.6 and Na+/Ca2+exchanger (NCX) within transverse (T)-tubules in DS-associated arrhythmias. METHODS: The authors undertook scanning ion conductance microscopy (SICM)-guided patch clamp, super-resolution microscopy, confocal Ca2+ imaging, and in vivo electrocardiography studies in Scn1a haploinsufficient murine model of DS. RESULTS: DS promotes INa,L in T-tubular nanodomains, but not in other subcellular regions. Consistent with increased NaV activity in these regions, super-resolution microscopy revealed increased NaV 1.6 density near Ca2+release channels, the ryanodine receptors (RyR2) and NCX in DS relative to WT hearts. The resulting INa,L in these regions promoted aberrant Ca2+ release, leading to ventricular arrhythmias in vivo. Cardiac-specific deletion of NaV 1.6 protects adult DS mice from increased T-tubular late NaV activity and the resulting arrhythmias, as well as sudden death. CONCLUSIONS: These data demonstrate that NaV 1.6 undergoes remodeling within T-tubules of adult DS hearts serving as a substrate for Ca2+ -mediated cardiac arrhythmias and may be a druggable target for the prevention of SUDEP in adult DS subjects.

Microwave Receiving System Based on Cryogenic Sensors for the Optical Big Telescope Alt-Azimuth.

This article presents the results of evaluating the possibility of conducting radio astronomy studies in the windows of atmospheric transparency ~100, ~230, and ~350 GHz using the optical Big Telescope Alt-Azimuthal (BTA) of the Special Astrophysical Observatory of the Russian Academy of Sciences (SAO RAS). A list of some promising astronomical tasks is proposed. The astroclimat conditions at the BTA site and possible optical, cryogenic, and mechanical interfaces for mounting a superconducting radio receiver at the focus of the optical telescope are considered. As a receiving system, arrays of detectors cooled to ~0.3 K based on the superconductor-insulator-normal metal-insulator-superconductor (SINIS) structure are proposed. The implementation of the project will make it possible to use the BTA site of the SAO RAS not only to solve some astronomical problems (it is possible to consider the implementation of a single observatory, the VLBI (very-long-baseline interferometry) mode in the Suffa, EHT (Event Horizon Telescope), and Millimetron projects), but it will also be used to test various cryogenic detectors in a real observatory.

Quasiepitaxial Aluminum Film Nanostructure Optimization for Superconducting Quantum Electronic Devices.

In this paper, we develop fabrication technology and study aluminum films intended for superconducting quantum nanoelectronics using AFM, SEM, XRD, HRXRR. Two-temperature-step quasiepitaxial growth of Al on (111) Si substrate provides a preferentially (111)-oriented Al polycrystalline film and reduces outgrowth bumps, peak-to-peak roughness from 70 to 10 nm, and texture coefficient from 3.5 to 1.7, while increasing hardness from 5.4 to 16 GPa. Future progress in superconducting current density, stray capacitance, relaxation time, and noise requires a reduction in structural defect density and surface imperfections, which can be achieved by improving film quality using such quasiepitaxial growth techniques.

NaV1.6 dysregulation within myocardial T-tubules by D96V calmodulin enhances proarrhythmic sodium and calcium mishandling.

Calmodulin (CaM) plays critical roles in cardiomyocytes, regulating Na+ (NaV) and L-type Ca2+ channels (LTCCs). LTCC dysregulation by mutant CaMs has been implicated in action potential duration (APD) prolongation and arrhythmogenic long QT (LQT) syndrome. Intriguingly, D96V-CaM prolongs APD more than other LQT-associated CaMs despite inducing comparable levels of LTCC dysfunction, suggesting dysregulation of other depolarizing channels. Here, we provide evidence implicating NaV dysregulation within transverse (T) tubules in D96V-CaM-associated arrhythmias. D96V-CaM induced a proarrhythmic late Na+ current (INa) by impairing inactivation of NaV1.6, but not the predominant cardiac NaV isoform NaV1.5. We investigated arrhythmia mechanisms using mice with cardiac-specific expression of D96V-CaM (cD96V). Super-resolution microscopy revealed close proximity of NaV1.6 and RyR2 within T-tubules. NaV1.6 density within these regions increased in cD96V relative to WT mice. Consistent with NaV1.6 dysregulation by D96V-CaM in these regions, we observed increased late NaV activity in T-tubules. The resulting late INa promoted aberrant Ca2+ release and prolonged APD in myocytes, leading to LQT and ventricular tachycardia in vivo. Cardiac-specific NaV1.6 KO protected cD96V mice from increased T-tubular late NaV activity and its arrhythmogenic consequences. In summary, we demonstrate that D96V-CaM promoted arrhythmias by dysregulating LTCCs and NaV1.6 within T-tubules and thereby facilitating aberrant Ca2+ release.

MATE1 Deficiency Exacerbates Dofetilide-Induced Proarrhythmia.

Dofetilide is a rapid delayed rectifier potassium current inhibitor widely used to prevent the recurrence of atrial fibrillation and flutter. The clinical use of this drug is associated with increases in QTc interval, which predispose patients to ventricular cardiac arrhythmias. The mechanisms involved in the disposition of dofetilide, including its movement in and out of cardiomyocytes, remain unknown. Using a xenobiotic transporter screen, we identified MATE1 (SLC47A1) as a transporter of dofetilide and found that genetic knockout or pharmacological inhibition of MATE1 in mice was associated with enhanced retention of dofetilide in cardiomyocytes and increased QTc prolongation. The urinary excretion of dofetilide was also dependent on the MATE1 genotype, and we found that this transport mechanism provides a mechanistic basis for previously recorded drug-drug interactions of dofetilide with various contraindicated drugs, including bictegravir, cimetidine, ketoconazole, and verapamil. The translational significance of these observations was examined with a physiologically-based pharmacokinetic model that adequately predicted the drug-drug interaction liabilities in humans. These findings support the thesis that MATE1 serves a conserved cardioprotective role by restricting excessive cellular accumulation and warrant caution against the concurrent administration of potent MATE1 inhibitors and cardiotoxic substrates with a narrow therapeutic window.

Association between Polymorphisms in CFH, ARMS2, CFI, and C3 Genes and Response to Anti-VEGF Treatment in Neovascular Age-Related Macular Degeneration.

Neovascular age-related macular degeneration (nAMD) is the leading cause of vision loss in the elderly. The gold standard of nAMD treatment is intravitreal injections of vascular endothelial growth factor (VEGF) inhibitors. Genetic factors may influence the response to anti-VEGF therapy and result in a high degree of response variability. The aim of the study was to evaluate the association of the polymorphisms in genes related to the complement system (rs2285714-CFI, rs10490924-ARMS2, rs2230199-C3, rs800292-CFH, and rs6677604-CFH) with nAMD its clinical features and optical coherent tomography (OCT) biomarkers of treatment response to anti-VEGF therapy. Genotyping by allele-specific PCR was performed in 193 AMD patients and 147 age-matched controls. A prospective study of the dynamics of changes in OCT biomarkers during aflibercept treatment included 110 treatment-naive patients. Allele T rs10490924 was associated with the increased risk of nAMD. For both rs800292 and rs6677604, carriage of the A allele was protective and decreased the nAMD risk. Associations of rs2230199 with central retinal thickness (CRT) and intraretinal cysts were revealed. The height of pigment epithelium detachment and the height of neuroretinal detachment were significantly higher in carriers of the minor allele of rs2285714, both at baseline and during treatment. The reduction of CRT was associated with higher CRT at baseline and the presence of the T allele of rs2285714. By the end of one-year follow-up the patients homozygous for the minor allele rs2285714 had significantly higher odds of the presence of anastomoses and loops and active neovascular membrane. Furthermore, minor allele carriers had decreased levels of complement factor I level in aqueous humor but not in the plasma, which may be due to the influence of rs2285714 on tissue-specific splicing. Our results suggest that the severity of AMD macular lesions is associated with rs2285714 and rs2230199 polymorphisms, which could be explained by their high regulatory potential. Patients with the minor allele of rs2285714 respond worse to antiangiogenic therapy.

Durable strong efficacy and favorable long-term renal safety of the anatomically optimized distal renal denervation according to the 3 year follow-up extension of the double-blind randomized controlled trial.

BACKGROUND: Historical reports on surgical renal denervation consistently describe renal plexus as a triangle or fan-like structure converging at the kidney gate. Following that anatomy, we developed a distal mode of radiofrequency renal denervation (RDN) mainly in segmental branches of the renal artery and confirmed its superior efficacy over the conventional main trunk procedure in a 6-months double-blind randomized controlled trial (NCT02667912). To assess the long-term effects of distal RDN we extended the follow-up of our study to three years. METHODS: BP, serum creatinine, eGFR were measured one and three years after randomization; major adverse renal events were assessed over the entire study period. The blinding was maintained over the entire three-year study period. FINDINGS: Of 55 randomized patients, 47 (23/24, distal/main trunk RDN, respectively) were assessed at one year and 39 (21/18) at three years post-procedure. Twenty-four-hour ambulatory systolic BP remained powerfully lowered after distal RDN both at one- and three-years assessments(mean change from baseline: -18.0, 95% CI -27.6 to -8.5; p<0.05 and -16·9, 95% CI -27·3 to -6·5; p<0·05, mmHg, respectively. This was accompanied by a moderate drop in eGFR at one year: -8·9 ml/min/m2, 95% CI -14·8 to -3·1; p<0·05, which, however, subsequently decreased in size at three years: -6·5, 95% CI -13·2 to 0·3; p>0·05. After main trunk RDN, the decrease of 24h systolic BP was quite moderate at one year: -12·1, 95% CI -19·2 to -5·0; p<0·05, and further weakened at three-year assessment: -8·5, 95% CI -19·7 to 2·2; p>0.05. eGFR was almost unchanged at one year: -1·3, 95% CI -6·6 to 4·0; p>0·05, but significantly decreased at three years: -5·0, 95% CI -9·6 to -0·3; p<0·05. INTERPRETATION: Our data demonstrate the durable strong BP-lowering efficacy and favorable long-term renal safety of distal RDN.

Characterization of Inactivated Influenza Vaccines Used in the Russian National Immunization Program.

BACKGROUND: today's standard quality control methods used to control the protein composition of inactivated influenza vaccines only take into account a few key reference components. They do not allow for thorough characterization of protein compositions. As a result, observation of unpredictable variations in major viral constituents and admixtures of cellular proteins within manufactured vaccines that may seriously influence the immunogenicity and safety of such vaccines has become a pressing issue in vaccinology. This study aims at testing a more sophisticated approach for analysis of inactivated split influenza vaccines licensed in the Russian Federation. The formulations under study are the most available on the market and are included in the Russian National Immunization Program. METHODS: liquid chromatography with tandem mass spectrometry (LC-MS/MS) analysis, in combination with label-free protein quantitation via the intensity-based absolute-quantitation (iBAQ) algorithm, as well as a number of standard molecular analysis methods, such as sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), dynamic light scattering (DLS), and negative-stain transmission electron microscopy (TEM) were applied. RESULTS: the methods implemented were able to identify dozens of viral and host proteins and quantify their relative amounts within the final formulations of different commercially available inactivated split influenza vaccines. Investigation of molecular morphology of the vaccine preparations using TEM revealed typical rosettes of major surface proteins (hemagglutinin and neuraminidase). DLS was used to demonstrate a size distribution of the rosettes and to test the stability of vaccine preparations at increased temperatures. CONCLUSIONS: a holistic approach based on modern, highly productive analytical procedures was for the first time applied for a series of different commercially available inactivated split influenza vaccines licensed in Russia. The protocols probed may be suggested for the post-marketing quality control of vaccines. Comparison of different preparations revealed that the Ultrix® and Ultrix® Quadri vaccines produced by pharmaceutical plant FORT LLC and trivalent vaccine Vaxigrip® produced by pharmaceutical company Sanofi Pasteur have well-organized antigen rosettes, they contain fewer admixture quantities of host cell proteins, and demonstrate good correlation among mostly abundant viral proteins detected by different methods.

Research of gnostic functions in the elderly people suffering from dementia

The study was aimed at investigating the features of gnostic functions in the elderly people suffering from dementia. To implement the objectives of the study and to solve the set tasks, the following methods were used: visual gnosis tests (recognition of images, the selection of three subject pictures, selecting parts of a whole, etc.), the acoustic gnosis tests (score and perception of rhythms, recognition of nonspeech sounds), and tactile gnosis tests (tactile identification, Teuber test, Foerster test). When running the visual gnosis tests, the elderly people with the dementia diseases slowly initiated the tasks, made numerous errors, and sometimes could not cope with the tasks at all. Also, the perception integrity disorders, the presence of fragmentation, lack of accuracy, differentiation, preservation of specific objective images-objects, and the violation in the understanding of the spatial arrangement of things were revealed. When performing the auditory-motor coordination tests, the elderly people suffering from dementia needed more time to listen to, they asked for the repeated sound representation, and there were often errors in the rhythmic structure reproduction. When performing the tactile gnosis tests, the elderly people suffering from dementia had difficulties in identifying the subject by touch, in understanding the right and left-sided spatial relationships, and also made errors in recognizing one of the touches when the experimenter touched their hands. Based on the study results, the recommendations have been developed for the preservation and improvement of the existing gnostic functions' disorders in the elderly people suffering from dementia. The recommendations are complex, and they can also be useful for the medical staff whose professional activity is directly related to the elderly people suffering from dementia, their relatives and the persons closest to them.

Risk factors and inflammatory predictors for Anastomotic Leakage following Total Mesorectal Excision with defunctioning stoma.

BACKGROUND: This study aims to examine the factors involved in anastomotic leak (AL) following low anterior resection and total mesorectal excision (LAR-TME) and to determine the usefulness of early measurement of the inflammatory biomarkers C-Reactive Protein (CRP) and Procalcitonin (PCT). METHODS: One hundred patients undergoing LAR-TME with a proximal diverting stoma were analyzed between 2013 and 2016. Postoperative CRP and PCT levels were measured on the 3rd and the 6th postoperative days. RESULTS: There were 11 clinical leaks with a negative impact in univariate analysis on AL of male gender, larger and stenotic tumours, intraoperative blood loss > 200 mL, the need for perioperative blood transfusion, postoperative anaemia and an operating time exceeding 180 minutes. On multivariate analysis, only perioperative blood transfusion was an independent AL risk factor. Recorded CRP was higher in AL patients when compared with non-AL cases on both the 3rd postoperative day (152.4 mg/L vs. 93 mg/L, respectively; P < 0.0001) and the 6th postoperative day (130.5 mg/L vs. 68.2 mg/L; P < 0.0001). The PCT levels also significantly differed between AL and non-AL cases on the 3rd postoperative day (0.5 ng/mL vs. 0.2 ng/mL, respectively; P < 0.0001) and the 6th postoperative day (1.16 ng/mL vs. 0.1 ng/mL, respectively; P < 0.0001). Both CRP and PCT showed high negative predictive values (NPV) for the diagnosis of an AL on both postoperative days. CONCLUSION: Following low restorative proctectomy, the high NPV of CRP and PCT measurements for the diagnosis of anastomotic leaks may assist decision-making for early hospital discharge.