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Introduction. Presbyopia is a global problem affecting more than 1.5 billion people worldwide. Projections indicate an increase in the average age of the population to 40 years by 2050, which is associated with an increase in the presbyopia incidence and corresponding economic losses. Despite the widespread prevalence of presbyopia, there are currently no effective methods for early prevention and restoration of dynamic accommodation and a standardized approach to assessing age-related changes in the lens that underlie presbyopia. The purpose: to study the effect of age-related changes in the lens on accommodation and to consider modern pharmacological approaches to the prevention and treatment of presbyopia.Methods. A multicenter prospective study was conducted, including analysis of visual acuity, the nearest point of clear vision and the volume of accommodation in individuals aged 40 to 55 years. Study participants were prescribed pyrenoxine (Catalin) as eye drops three times daily for 4 months. The study included 382 questionnaires collected from 29 ophthalmologists.Results. As a result of the study, the average distance to the nearest point of clear vision decreased slightly, but the reserve of accommodation remained at the same level. This indicates the absence of significant progression of age-related decrease in the reserve of accommodation as one of the manifestations of presbyopia and the possible effectiveness of pyrenoxine in preserving the elastic properties of the lens.Conclusion. The study confirmed the effectiveness of pyrenoxine in the prevention of presbyopia and the preservation of accommodative abilities in middle-aged people. The concept of Dysfunctional Lens Syndrome may be useful for clinical practice by providing opportunities for early diagnosis and treatment of presbyopia. Incorporating this concept into clinical guidelines may improve approaches to the treatment and prevention of age-related lens changes.

Immune relationships involved in a wide range of immunopathological conditions, including ankylosing spondylitis (AS), are formed due to the characteristics of the subset composition of follicular T helper cells (Tfh) and B lymphocytes. Expression of the HLA-B27 antigen can change the reactivity of cells of the immune system and, accordingly, their interaction and participation in the immunopathogenesis of AS. The aim of this study was to investigate the characteristics of the subset composition of Tfh and B cells in HLA-B27-positive and negative patients with AS. Material and methods. 66 patients (17 women and 49 men) aged 20–58 years with a diagnosis of AS were examined. Molecular genetic research on HLA-B27 expression was carried out using the quantitative PCR method with real-time detection. The subset composition of Tfh and B cells was studied using flow cytometry. Results. An increase in the amount of Tfh2 in the blood is observed in all patients with AS. The number of Tfh1 was reduced in HLA-B27-positive AS patients, but Tfh17 cell content was increased. Changes in the subset composition of B lymphocytes, which were found only in patients with an HLA-B27-positive form of the disease, manifest themselves primarily as an imbalance in the distribution of B cell memory. Only negative correlations of Tfh1 and Tfh17 content with “double-negative” B cell and plasmablast precursors percentage are detected in HLA-B27-negative AS patients. Tfh1 cell number correlate negatively with naïve and activated naïve B cell content in HLA-B27-positive disease, Tfh2 cell percentage – with memory B cell fraction number. CCR6+ Tfh and Tfh17 have positive regulatory effects on plasmablast precursors. Conclusions. The subset composition of Tfh characterizes the dominance in the immunopathogenesis of AS of the direction of the regulatory influence of follicular T helper cells on B lymphocytes regardless of the carriage of the HLA-B27 gene in AS patients. High levels of Tfh type 17 are also detected in HLA-B27-positive patients. The relationships between the subsets of Tfh and B cells in HLA-B27-negative AS patients characterize the presence of processes aimed at inhibiting B cells. The influence of Tfh1 is aimed at suppression of B-cell immunity in HLA-B27-positive AS while Tfh2 and Tfh17 stimulate B-cell mechanisms.

Introduction. While developing the algorithms for diagnosis and treatment of patients with thermal injury, an injury outcome prediction index with the best predictive properties should be used.Aim. To compare the predictive properties of the Revised Frank Index and other specialized indices.Material and methods. A retrospective observational study included 307 patients with thermal injury, of whom 80 (26%) died. We compared the discriminatory ability, as well as sensitivity, specificity, positive predictive value and negative predictive value, the accuracy of the diagnostic test in relation to predicting a fatal outcome for 8 specialized prediction indices: RFI, FI, Baux, RBS, PBI, ABSI, BOBI, and Ryan.Results. RFI showed the largest area under the ROC curve: 0.942 [0.913–0.971], other indices had a smaller area: FI 0.827 [0.768–0.886], Baux 0.860 [0.811–0.909], RBS 0.891 [0.848–0.933], PBI 0.893 [0.848–0.937], ABSI 0.838 [0.786–0.890], BOBI 0.865 [0.819–0.910], Ryan 0.816 [0.764–0.869]. The Ryan index had the highest sensitivity (95%), but its specificity (49%) was the lowest, and the proportion of false positive results was 60%. The RBS index had high sensitivity (84%) and specificity (80%), but the false positive rate was 40%. The RFI and PBI indices showed similar sensitivity (81%), however, the proportion of false positive results for RFI (23%) was lower than that of PBI (39%) and all other indices, and the RFI accuracy in predicting the outcome was the highest among the other indices, making 89%.Conclusion. The predictive properties of the Revised Frank Index are better than those of other specialized indices.

Aim. To study the functional activity of blood eosinophils in patients with Opisthorchis felineus (O. felineus) invasion.Material and methods. A total of 328 patients with O. felineus invasion (120 men and 208 women, mean age 40.3 years) and 34 practically healthy patients (14 men and 20 women, mean age 41.1 years) aged 18 to 70 years were examined. The main method for diagnosing opisthorchiasis was the determination of eggs or bodies of adult parasites in the duodenal contents and/or feces, which was used in all 328 patients with opisthorchiasis. All patients underwent a complete blood count and biochemical blood test, esophagogastroduodenoscopy and ultrasound examination of the abdominal organs. The study of the functional activity of blood eosinophils was carried out in 42 patients with opisthorchiasis and 34 healthy individuals from the control group by chemiluminescent analysis with the measurement of the intensity of production of reactive oxygen species in spontaneous and zymosan-induced reactions in lucigenin- and luminol-dependent processes.Results. The frequency of eosinophils in the complete blood count above 5% in the examined patients with opisthorchiasis was 19.5%. An increase in the content of eosinophils in the blood in patients with opisthorchiasis was associated with an increase in the frequency of complaints of pain in the right hypochondrium, pruritus, skin rashes, an increase in the proportion of leukopenia and neutropenia, an increase in the level of gamma-glutamyl transpeptidase in the blood, and an increase in the frequency of ultrasound signs of cholecystitis. At the same time, a pronounced increase in the functional activity of blood eosinophils, determined by the chemiluminescent method, was observed in patients with O. felineus invasion.Conclusions. Patients with O. felineus invasion with an increase in the content of eosinophils in the blood due to the likelihood of an aggressive course of the pathology deserve the close attention of practitioners with the need for a thorough comprehensive examination of patients, including immunological methods.

Elimination of the hepatitis C virus (HCV) due to direct antiviral drug (DAD) action affects alteration in virus phenotype and, accordingly, NK cell functional activity. However, the published data are very contradictory. The aim of the study was to investigae alterations in NK cell subset phenotype after DAD treatment of HCV genotype-dependent chronic viral hepatitis C (CVHC) patients. Materials and methods. 111 CVHC patients and 21 healthy volunteers were examined. The diagnosis was established on epidemiological, clinical and laboratory data. All 111 subjects with CVHC received direct antiviral drugs Sofosbuvir and Velpatasvir for 12 weeks. The study of the NK cell phenotypes wwas analyzed by multicolor flow cytometry. Results. A decreased count of cytokine-producing along with increased frequency of cytotoxic NK cells were found in CVHC patients blood samples with various HCV genotypes prior to DAD treatment. The imbalance of cytotoxic cells with a high level of functional activity was also found in CVHC patients regardless of HCV genotype. The patients with HCV genotypes 1 and 3 showed significantly increased level of immunoregulatory NK cells. In addition, increased count of glycohydrolase (CD38) and ecto-5'-nucleotidase (CD73)-expressing NK cells were found in patients with HCV genotypes 1 and 3. Hence, such alterations in NK cell phenotype in CVHC patients were presented as sustained high viral load which peaking at carriers of HCV genotype 1 that was minimal in patients with HCV genotype 2. The most prominent change in NK cells after DAD treatment was found in CVHC patients with HCV genotype 2 (normalization of CD8-expressing NK cell subset composition and count). Only patients with HCV genotype 2 after treatment had increased frequencies of peripheral blood double-negative CD38–CD73– NK cells. Patients with HCV genotypes 1 and 3 also showed minimally improved in NK cell subset composition after DAD treatment. Conclusion. Evaluation of specific changes in NK cell phenotype during DAD treatment of CVHC patients driven by HCV genotype undoubtedly is of importance and high relevance. The results obtained are novel and complement the insights into CVHC immunopathogenesis. Analysis of NK cell phenotypes and functional activity in patients with CVHC may promote development of new methods for treating HCV infection.

Abstract A combination of a high sediment input and intense bottom currents often leads to the formation of contourites (sediments deposited or significantly reworked by bottom currents). Both of these components are present in the Vema Fracture Zone valley which is the most important passageway for the distribution of the Antarctic Bottom Water from the West to the North-East of the Atlantic. However, no contourite drifts, moats or contourite channels have been found in this region in more than half a century of research. The prevailing sedimentation paradigm postulates that turbidity currents have predominantly governed sedimentation in this region during the Pleistocene. This work describes the first example of contourite depositional system identified in the Vema Fracture Zone. The discovery was made through detailed high-resolution sub-bottom profiling, as well as numerical modeling and direct measurements of bottom current velocities. Such systems are exceptionally uncommon in fracture zones. This study highlights the importance of further research of contourites along the Vema Fracture Zone based on modern concepts of contourite and mixed depositional systems. The work also emphasizes the need to reevaluate the impact of bottom currents on sedimentation in this region, and particularly in the narrow segments of the fracture zone valley.

The aim of our study was to investigate the main characteristics of peripheral blood NKT cell phenotype in patients with disseminated purulent peritonitis (DPP) in dynamics of postoperative period, depending on the disease outcome. Fifty-two patients with acute surgical diseases and injuries of the abdominal organs complicated by DPP, and 68 healthy individuals in control group, were examined. Blood sampling was performed before surgery (preoperative period), as well as on the day 7, 14 and 21 of postoperative period. All patients with DPP were divided into two groups depending on disease outcome in postoperative period: patients with favorable disease outcome (n = 34); and patients with unfavorable outcome (n = 18). Study of the phenotype of blood NKT lymphocytes was performed by flow cytometry using direct immunofluorescence of whole peripheral blood samples with monoclonal antibodies. The low relative and absolute level of NKT cells was observed in DPP patients regardless of outcome disease in preoperative period. At the same time, the absolute level of NKT cells returned to normal only in patients with favorable DPP outcome and only by day 21 after surgery. Patients with favorable DPP outcome by the end of examination period had normalized quantity of mature NKT-lymphocytes and significantly decreased level of cytotoxic cells which was apparently associated with migration of such cell subsets to site of inflammation. A reduced level of non-classical (expressing CD8 marker) mature and cytokine-producing NKT cells was detected only in patients with favorable DPP outcome in preoperative period which returned to normal by the end of postoperative period. At the same time, patients with unfavorable disease outcome had reduced quantity of NKT cells of these subsets by day 21 of postoperative treatment. Patients with favorable outcome had high level of mature and cytotoxic CD11b+ NKT cells already in the preoperative period, while patients with unfavorable DPP outcome had increased level of cytotoxic CD11b+ NKT cells only by day 21 after surgery. The proportion of NKT cells expressing activation markers (CD28 and CD57) was reduced in patients in preoperative period that returned to normal immediately after surgery with favorable outcome, while it recovered with unfavorable outcome closer to the end of postoperative examination. The defined features of NKT cell phenotype in patients with unfavorable DPP outcome characterize disturbances in subset ratio and mechanisms of functioning of this cell fraction. This determines a need to develop immunotherapeutic methods aimed at stimulating immunoregulatory activity of NKT cells.

The aim of the present study was to evaluate the subpopulation profile of T and B lymphocytes, and their relationships during therapy of the patients with Graves’ disease (GD) treated by means of radioactive iodine. We have examined 36 women with verified diagnosis of GD. The contents of thyroid hormones were determined by immunoradiometric analysis. The levels of thyroid-stimulating hormone receptor autoantibodies (rTSH) were evaluated by enzyme-linked immunosorbent assay. On the basis of comprehensive pre-therapeutic examination, all patients were exposed to the fixed-activity therapy with radioactive iodine-131 at a dose of 400 to 700 MBq administered orally in isotonic aqueous solution of sodium iodide. 56 practically healthy women were examined as a control group. The phenotype of T and B cells in whole blood was studied by flow cytometry using direct immunofluorescence. It was shown that the patients, prior to treatment with radioactive iodine, had high levels of cellular functional activity, as determined by expression of CD25 antigen on T cells and CD23-antigen on B lymphocytes. Higher functional activity of the cells responsive for adaptive immunity in the patients with GD manifests in the presence of increased levels of autoantibodies to rTSH. By means of correlation analysis, we found that the patients with GD examined before the therapy had the thyroid status may determine the functional stimulation of T and B cells, thus increasing the levels of autoimmune processes. One month after radioiodine therapy (RIT), the GD patients, along with transient hyperthyroidism with increased concentration of autoantibodies to rTSH, showed a reduction of activated T lymphocyte contents (including T helpers and cytotoxic T cells) to control values. However, the level of cytotoxic T lymphocytes in the blood remained low, and the content of Treg cells was significantly increased in the patients. Decreased contents of B cells activated memory B cell to the control levels were found in patients with GD over 1 month after RIT when studying the phenotype of blood B lymphocytes. In this case, increased levels of naive B lymphocytes and B2 cells were detected, as well as decreased numbers of activated B1 lymphocytes. The observed changes in the subpopulation composition of T and B cells, and in their phenotype developed against the background of complete absence of relationships between the studied parameters, thus suggesting loss of thyroid control of immune processes and cooperative cell interaction during the development of the immune response. Generally, the phenotypic changes of T and B lymphocyte subsets in the blood of patients with GD through 1 month after treatment with radioactive iodine may reflect a trend for decreased functional activity of adaptive cellular immunity which may also account for inhibition of autoimmune processes.

Introduction. There is a discussion about which genotype of viral hepatitis C (HCV) is the most aggressive. Some authors consider that the 1st genotype is the most aggressive, others define the 3rd HCV genotype as a factor that determines the high activity of the pathological process. The solution of this issue is important for optimizing the tactics of patient management.Aim. To compare the clinical and laboratory characteristics and the incidence of liver fibrosis in patients with chronic viral hepatitis C of the first and third genotypes.Materials and methods. 297 patients with genotype 1 of HCV and 231 patients with genotype 3 of HCV were examined. The diagnosis of chronic viral hepatitis C was established according to the recommendations of the European Association for the Study of the Liver (2016, 2018). Liver fibrosis was studied by shear wave transient elastometry with METAVIR score.Results and discussion. The frequency of elevated ALT in the blood prevailed in patients with HCV genotype 3 compared with persons with HCV genotype 1 (90.5% vs. 82.8%, p = 0.02). ALT levels above 3 norms were registered in 29.0% of patients with genotype 3 and in 16.8% patients with HCV genotype 1 (p = 0.001). The frequency of liver fibrosis F2 according to METAVIR was 11.8% in patients with genotype 1 and 21.2% in patients with genotype 3 of HCV (p = 0.005); the frequency of liver fibrosis F3–F4 according to METAVIR was 20.5% in patients with genotype 1 and 32.5% in patients with genotype 3 of HCV (p = 0.003). The combination of high viral load and high inflammatory activity, which was associated with liver fibrosis F3–F4 according to METAVIR in both compared groups, was determined in 16.9% of patients with genotype 3 and only in 10.4% of patients with genotype 1 of HCV (p = 0.04).Conclusion. The obtained data allow us to consider that in the surveyed population the course of chronic viral hepatitis C with genotype 3 is clearly more aggressive than in persons with genotype 1 of HCV.

Objective: to construct geometric models of carotid bifurcation and build a computer modeling for carotid endarterectomy (CEA) operations with patches of various configurations.Materials and methods. The method uses reconstructed models of a healthy blood vessel obtained from a preoperative computed tomography (CT) study of the affected blood vessel of a particular patient. Flow in the vessel is simulated by computational fluid dynamics using data from the patient's ultrasonic Doppler velocimetry and CT angiography. Risk factors are assessed by hemodynamic indices at the vessel wall associated with Wall Shear Stress (WSS).Results. We used the proposed method to study the hemodynamic results of 10 virtual CEA operations with patches of various shapes on a reconstructed healthy artery of a particular patient. The reason for patch implantation was to ensure that the vessel lumen is not narrowed as a result of the surgery, since closing the incision without a patch can reduce the vessel lumen circumference by 4–5 mm, which adversely affects blood flow. On the other hand, too wide a patch creates aneurysmorphic deformation of the internal carotid artery (ICA) mouth, which is not optimal due to formation of a large recirculation zone. In this case, it was found that the implanted patch width of about 3 mm provides an optimal hemodynamic outcome. Deviations from this median value, both upward and downward, impair hemodynamics. The absence of a patch gives the worst of the results considered.Conclusion: The proposed computer modeling technique is able to provide a personalized patch selection for classical CEA with low risk of restenosis in the long-term follow-up.

The aim of current study was to compare profiles of T cell subsets in the patients with ankylosing spondylitis (AS) who received different modes of genetically engineered biological therapy (GEBT). The research involved 58 patients aged 20 to 58 years diagnosed with AS and treated with anti-TNFα and antiIL-17 drugs, as well as those receiving common anti-inflammatory therapy. The AS diagnostics was based on the modified New York criteria. Disease activity was assessed by means of nomenclature approved by the Assessment of Spondyloarthritis International Society and Outcome Measures in Rheumatology. 45 healthy people aged 18 to 57 were included into the control group. Peripheral blood T cell subsets were analysed by multicolor flow cytometry. It was found that the T lymphocyte subpopulation profiles in AS patients showed significant differences depending on the therapy type. First, T lymphocyte counts were decreased in AS patients receiving traditional anti-inflammatory therapy, whereas relative numbers of T cells with high levels of effector potential and cytokine secretion were increased. Negative correlations between the levels of effector memory and pre-effector cytotoxic T cells and other laboratory and clinical indexes of inflammatory activity in AS may reflect lower efficiency of traditional therapy. Next, the levels of main T cell subsets in AS patients during antiIL-17 therapy fully corresponded to the control values. However, based on numerous correlations between immunological and clinical laboratory parameters, it was concluded that anti-IL-17 therapy had an inhibitory effect on the joint inflammation activity, while the state of T cell subsets was mainly dependent on standard anti-inflammatory therapy. The most pronounced changes in T cell subsets were found in AS patients during anti-TNFα therapy was associated with decreased effector potential of Th cells and cytotoxic T lymphocytes. At the same time, the lowest frequency of extraskeletal manifestations was found in AS patients treated with anti-TNFα drugs. Finally, the higher efficiency of GEBT, compared with conventional methods of therapy, is determined by the effects upon immune targets of AS pathogenesis which manifested, e.g., by changes in the T lymphocyte subpopulation profile. Moreover, usage of anti-TNFα versus anti-IL-17 inhibitors was associated with greater effect upon phenotypic profile of T cells.

Triazole fungicides are widely used in agricultural production for plant protection, including pea (Pisum sativum L.). The use of fungicides can negatively affect the legume-Rhizobium symbiosis. In this study, the effects of triazole fungicides Vintage and Titul Duo on nodule formation and, in particular, on nodule morphology, were studied. Both fungicides at the highest concentration decreased the nodule number and dry weight of the roots 20 days after inoculation. Transmission electron microscopy revealed the following ultrastructural changes in nodules: modifications in the cell walls (their clearing and thinning), thickening of the infection thread walls with the formation of outgrowths, accumulation of poly-β-hydroxybutyrates in bacteroids, expansion of the peribacteroid space, and fusion of symbiosomes. Fungicides Vintage and Titul Duo negatively affect the composition of cell walls, leading to a decrease in the activity of synthesis of cellulose microfibrils and an increase in the number of matrix polysaccharides of cell walls. The results obtained coincide well with the data of transcriptomic analysis, which revealed an increase in the expression levels of genes that control cell wall modification and defense reactions. The data obtained indicate the need for further research on the effects of pesticides on the legume-Rhizobium symbiosis in order to optimize their use.

Post-COVID syndrome develops in 10–20% of people who have recovered from COVID-19 and it is characterized by impaired function of the nervous, cardiovascular, and immune systems. Previously, it was found that patients who recovered from infection with the SARS-CoV-2 virus had a decrease in the number and functional activity of NK cells. The aim of the study was to assess the effectiveness of recombinant human IL-2 (rhIL-2) administered to correct NK cell phenotype and functional activity in patients with post-COVID syndrome. Patients were examined after 3 months for acute COVID-19 of varying severity. The phenotype of the peripheral blood NK cells was studied by flow cytometry. It was found that disturbances in the cell subset composition in patients with post-COVID syndrome were characterized by low levels of mature (p = 0.001) and cytotoxic NK cells (p = 0.013), with increased release of immature NK cells (p = 0.023). Functional deficiency of NK cells in post-COVID syndrome was characterized by lowered cytotoxic activity due to the decreased count of CD57+ (p = 0.001) and CD8+ (p < 0.001) NK cells. In the treatment of patients with post-COVID syndrome with recombinant IL-2, peripheral blood NK cell count and functional potential were restored. In general, the effectiveness of using rhIL-2 in treatment of post-COVID syndrome has been proven in patients with low levels of NK cells.

Th cells may exhibit pathological activity depending on the regulatory and functional signals sensed under a wide range of immunopathological conditions, including ankylosing spondylitis (AS). The relationship between Th cells and cytokines is important for diagnoses and for determining treatment. Accordingly, the aim of this study was to investigate the relationship between Th-cell subset composition and serum cytokine profile for patients with activity-driven AS. In our study, patients were divided into two groups according to disease activity: low-activity AS (ASDAS-CRP < 2.1) and high-activity AS (ASDAS-CRP > 2.1). The peripheral blood Th cell subset composition was studied by flow cytometry. Using multiplex analysis, serum cytokine levels were quantified and investigated. It was found that only patients with high-activity AS had reduced central memory (CM) Th1 cells (p = 0.035) but elevated numbers of CM (p = 0.014) and effector memory (EM) Th2 cells (p < 0.001). However, no activity-driven change in the Th17 cell subset composition was observed in AS patients. Moreover, low-AS activity patients had increased numbers of Tfh17 EM cells (p < 0.001), whereas high-AS activity was associated with elevated Tfh2 EM level (p = 0.031). The serum cytokine profiles in AS patients demonstrated that cues stimulating cellular immunity were increased, but patients with high-AS activity reveled increased IL-5 level (p = 0.017). Analyzing the data obtained from AS patients allowed us to conclude that Th cell subset differentiation was mainly affected during the CM stage and characterized the IL-23/IL-17 regulatory axis, whereas increased humoral immunity was observed in the high-AS activity group.

Aim. To study the activity of neutrophilic granulocytes in patients with opisthorchiasis, depending on the severity of liver fibrosis. Materials and methods. A total of 74 patients with chronic opisthorchiasis (39 men and 35 women, average age 42.3 years) and 32 practically healthy patients (17 men and 15 women, average age 41.5 years) aged 24 to 60 years were examined. Diagnosis of opisthorchiasis was carried out by two methods: coprooscopy and identification of eggs or bodies of adult parasites in duodenal content. Liver fibrosis was determined by the method of elastometry according to the METAVIR scale in all 74 patients with opisthorchiasis. The study of the functional activity of neutrophils in the blood was performed to all 74 patients with opisthorchiasis and 32 healthy individuals from the control group by chemiluminescent analysis with measurement of the reactive oxygen species (ROS) production intensity in a spontaneous and zymosan-induced reaction in lucigenin and luminol-dependent processes. Results. Liver fibrosis F2 by METAVIR was registered in 20.3% of the examined individuals, liver fibrosis F3F4 by METAVIR was detected in 17.6% of patients with opisthorchiasis. In patients with opisthorchiasis with liver fibrosis F3F4 by METAVIR, a significant decrease in the functional activity of neutrophilic granulocytes was registered in comparison with individuals with liver fibrosis F0F1 by METAVIR, as evidenced by a significant decrease in the maximum intensity of ROS production (Imax) and the area under the curve (S) chemiluminescence in lucigenin and luminol-dependent processes both in the spontaneous and zymosan-induced reaction. Conclusion. These results provide new information to explain the mechanisms of liver fibrosis in patients opisthorchiasis and create opportunities for the development of diagnostics and preventive technologies.

The interactions of the excited states of a single chromophore with static and dynamic electric fields spatially varying at the atomic scale are investigated in a joint experimental and theoretical effort. In this configuration, the spatial extension of the fields confined at the apex of a scanning tunneling microscope tip is smaller than that of the molecular exciton, a property used to generate fluorescence maps of the chromophore with intramolecular resolution. Theoretical simulations of the electrostatic and electrodynamic interactions occurring at the picocavity junction formed by the chromophore, the tip, and the substrate reveal the key role played by subtle variations of Purcell, Lamb, and Stark effects. They also demonstrate that hyper-resolved fluorescence maps of the line shift and linewidth of the excitonic emission can be understood as images of the static charge redistribution upon electronic excitation of the molecule and as the distribution of the dynamical charge oscillation associated with the molecular exciton, respectively.

Background: Pulsed field ablation (PFA) is a novel technology for catheter-based atrial arrhythmia treatment. Evidence of its application for ventricular arrhythmia ablation is still limited. In this study, we describe the feasibility and efficacy of focal PFA for premature ventricular contraction (PVC) ablation., Methods: A prospective cohort of 20 patients referred for PVC ablation at 2 centers was enrolled, regardless of the presence of structural heart disease, PVC morphology, or previous ablation attempts. All procedures were performed using the CENTAURI System in combination with contact force sensing catheters and 3-dimensional electroanatomical mapping systems. Energy output and the number of applications were left to the operator's discretion., Results: Eleven (55%) procedures were conducted under general anesthesia, 6 (30%) under deep sedation, and 3 (15%) under light sedation. Muscular contraction was observed in one case (5%). Median procedural and fluoroscopy times were 95.5 and 6.55 minutes, respectively. The median number of PFA applications was 8 with a median contact force of 10 g . A statistically significant (76%) reduction was observed in mean peak-to-peak bipolar electrogram voltage before and after ablation (0.707 versus 0.098 mV; P =0.008). Ventricular irritative firing was observed in 11 (55%) patients after PFA. The median follow-up was 120 days. Acute procedural success was achieved in 17 of 20 (85% [95% CI, 0.70-1]) patients. Two of the patients with procedural failure had late success with >80% clinical PVC burden suppression during follow-up, and 2 of 17 patients with acute success had late PVC recurrence, which accounts for a total of 17 of 20 (85% [95% CI, 0.70-1]) patients with chronic success. Transient ST-segment depression occurred in 1 patient, and the right bundle branch block was induced in 2 others (permanently only in one case)., Conclusions: PVC ablation using a focal PFA is feasible, effective, and safe, with promising acute and long-term results in several ventricular locations. Irritative firing is frequently observed. Coronary evaluation should be considered when targeting the outflow tract., Competing Interests: Dr La Meir is a consultant for AtriCure. Dr Chierchia received compensation for teaching purposes and proctoring from Medtronic, Abbott, Biotronik, Boston Scientific, and Acutus Medical. Dr Chierchia received compensation for teaching purposes and proctoring from Medtronic, Abbott, Biotronik, Boston Scientific, and Acutus Medical. Dr de Asmundis received research grants on behalf of the center from Biotronik, Medtronic, Abbott, LivaNova, Boston Scientific, AtriCure, Philips, and Acutus and compensation for teaching purposes and proctoring from Medtronic, Abbott, Biotronik, LivaNova, Boston Scientific, AtriCure, Acutus Medical, and Daiichi Sankyo. Dr Sorgente is a consultant for Biosense Webster and Abbott and received compensation for teaching purposes from Medtronic, Biotronik, and Microport. The other authors report no conflicts.

Solid-state supercapacitors with gel electrolytes have emerged as a promising field for various energy storage applications, including electronic devices, electric vehicles, and mobile phones. In this study, nanocomposite gel membranes were fabricated using the solution casting method with perfluorosulfonic acid (PFSA) ionomer dispersion, both with and without the incorporation of 10 wt.% montmorillonite (MMT). MMT, a natural clay known for its high surface area and layered structure, is expected to enhance the properties of supercapacitor systems. Manganese oxide, selected for its pseudocapacitive behavior in a neutral electrolyte, was synthesized via direct co-precipitation. The materials underwent structural and morphological characterization. For electrochemical evaluation, a two-electrode Swagelok cell was employed, featuring a carbon xerogel negative electrode, a manganese dioxide positive electrode, and a PFSA polymer membrane serving as both the electrolyte and separator. The membrane was immersed in a 1 M Na 2 SO 4 solution before testing. A comprehensive electrochemical analysis of the hybrid cells was conducted and compared with a symmetric carbon/carbon supercapacitor. Cyclic voltammetric curves were recorded, and galvanostatic charge-discharge tests were conducted at various temperatures (20, 40, 60 °C). The hybrid cell with the PFSA/MMT 10 wt.% exhibited the highest specific capacitance and maintained its hybrid profile after prolonged cycling at elevated temperatures, highlighting the potential of the newly developed membrane.

This work presents research on thin magnetron-sputtered platinum (Pt) films deposited over commercial gas diffusion electrodes and applied to convert and pressurize hydrogen in an electrochemical hydrogen pump. The electrodes were integrated into a membrane electrode assembly with a proton conductive membrane. Their electrocatalytic efficiency toward hydrogen oxidation and hydrogen evolution reactions was studied in a self-made laboratory test cell by means of steady-state polarization curves and cell voltage measurements (U/j and U/p diff characteristics). The achieved current density at a cell voltage of 0.5 V, the atmospheric pressure of the input hydrogen, and a temperature of 60 °C was more than 1.3 A cm -2 . The registered increase in the cell voltage with the increasing pressure was only 0.05 mV bar -1 . Comparative data with commercial E-TEK electrodes reveal the superior catalyst performance and essential cost reduction of the electrochemical hydrogen conversion on the sputtered Pt films.

A novel strain of Gram-positive bacteria Paenibacillus profundus YoMME was recognized by sequencing of 16S rRNA gene and after that tested for exoelectrogenicity for the first time. It was found that at an applied potential of -0.195 V (vs. SHE) the bacteria are capable of generating electricity and forming electroactive biofilms for 3-4 days. A tendency for the decrease in double-layer capacitance and the increase in the charge transfer resistance during the maturation of the biofilm was established. The formed bioanodes were used as a part of a membrane-electrode assembly (MEA) together with a selected cathode (E-Tek) and a separator (Zirfon). The applicability of MEA with the bioanode was tested by operating a newly designed bioelectrochemical system in a microbial fuel cell (MFC) or microbial electrolysis cell (MEC) mode. A current density of 200 mA m -2 was generated by the MFC after the improvement of the cathodic reaction through facilitated air access. The Coulombic efficiency in different MFC runs ranged from 5.2 to 7.4%. It was also determined that 0.65 V applied cell voltage is appropriate for the operation of the cell in the electrolysis mode, during which a current density of 2-3 Am -2 was reached. This, along with the evolved gas on the cathode, shows that as an anodic biocatalyst P. profundus YoMME assists the electrolysis processes at a significantly lower voltage than the theoretical one (1.23 V) for water decomposition. The hydrogen production rate varied between 0.5 and 0.7 m 3 /m 3 d and the cathodic hydrogen recovery ranged from 49.5 to 61.5 %. The estimated energy efficiency based on the electricity input exceeds 100 %, which indicates that additional energy is being gained from the biotic oxidation of the available organics., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)