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The problem of chronic rhinitis (CR) remains unresolved in the world, while it has a negative impact on the quality of life of patients. Chronic forms of rhinitis suffer from 10-20% of the population, and its symptoms in epidemiological studies are noted in 40% of respondents. One of the leading mechanisms of disease occurrence is oxidative stress., Objective: To study the state of the processes of lipid peroxidation and antioxidant protection in various types of chronic rhinitis., Material and Methods: The study included 50 patients with CR, of which 21 were with chronic allergic rhinitis (CALR), 20 with chronic vasomotor rhinitis (CVR), 9 with chronic atrophic rhinitis (CAR). The control group was represented by 50 practically healthy volunteers with no otorhinolaryngological complaints. The indicators of the LPO-AOD system in erythrocytes were evaluated by spectrophotometric methods. Statistical data processing was carried out using the Statistica 7.0 software package (StatSoft, USA)., Results: In all patients with CR in the blood erythrocytes, an increase in the level of malondialdehyde (MDA), a decrease in the activity of superoxide dismutase (SOD), catalase (CAT) relative to the control group was found. With CAR, the most pronounced changes are determined, with CVR - minimal. In patients with CR, lipid peroxidation is activated, MDA increases by 1.29 times, by 1.37 times with CAR, and by 1.31 times with CALR relative to normal values. The activity of the antioxidant system decreases, which reflects the classical variant of inhibition of antioxidant enzymes: SOD is reduced by 1.08 times in CAR, by 1.07 times in CALR, and 1.04 times in CVR, CAT in CAR is reduced by 1.02 times; CALR by 1.02 times, with CVR by 1.01 times. The coefficient of oxidative stress with CVR is 1.36, with CAR is 1.5, with CALR is 1.42., Conclusion: In CR, the predominance of pro-oxidant processes over antioxidant ones is revealed, a slight oxidative stress is detected, probably due to the presence of hypoxia and intoxication syndrome. An in-depth study of lipid peroxidation processes and factors of the antioxidant defense system, depending on the CR phenotype, can be used to correct therapy and prevent exacerbations, as well as markers of progression and prognosis of chronic rhinitis.

Renal artery denervation (RDN) has been proposed for resistant arterial hypertension. Beyond conventional radiofrequency (RF) ablation, there are emerging RDN technologies, including laser catheter ablation. We aimed at evaluamting the local effects of laser ablation on the renal artery and perivascular nerve injury in comparison with radiofrequency ablation. Thirteen pigs (mean weight 36.7 ± 4.7 kg, age 3 months) were divided into three groups: (1) laser ablation in normotensive pigs (LA; n = 3), (2) bipolar RF ablation in normotensive pigs (RF; n = 7), and (3) a sham group (SHAM; n = 3). Transcatheter laser and RF ablations were performed under general anesthesia. After euthanasia, pathology and immunohistochemical studies were performed. Artery wall and perivascular nerve lesions were found in the LA and RF groups. A lower rate of intimal microdissections was evaluated after laser ablation when compared with RF ablation (0 vs. 1.5 [1;2.75] per artery; p < .05). There was a numerical prevalence of nerves with tyrosine hydroxylase expression loss after laser RDN when compared with RF ablation (16.7 [4; 18] vs. 9.1 [0;18] per specimen). Laser ablation is noninferior to RF ablation regarding perivascular nerve injury and is associated with less intimal layer damage., (© 2022 American Association for Anatomy.)

Background: Mechanisms of positive effects of pulmonary artery (PA) denervation (PADN) remain poorly understood. The study aimed to evaluate pulmonary hemodynamic changes after PADN and their association with the extent of PA wall damage in an acute thromboxane A2 (TXA2)-induced pulmonary hypertension (PH) model in swine., Methods: In this experimental sham-controlled study, 17 normotensive male white Landrace pigs (the mean weight 36.2 ± 4.5 kg) were included and randomly assigned to group I (n = 9)-PH modeling before and after PADN, group II (n = 4)-PADN only, or group III (n = 4)-PH modeling before and after a sham procedure. Radiofrequency (RF) PADN was performed in the PA trunk and at the proximal parts of the right and left PAs. PA wall lesions were characterized at the autopsy study using histological and the immunohistochemical examination., Results: In groups I and II, no statistically significant changes in the mean pulmonary arterial pressure nor systemic blood pressure were found after PADN (-0.8 ± 3.4 vs 4.3 ± 8.6 mmHg, P = 0.47; and 6.0 ± 15.9 vs -8.3 ± 7.5 mmHg, P = 0.1; correspondingly). There was a trend towards a lower diastolic pulmonary arterial pressure after PADN in group I when compared with group III during repeat PH induction (34.4 ± 2.9 vs 38.0 ± 0.8; P = 0.06). Despite the presence of severe PA wall damage at the RF application sites, S100 expression was preserved in the majority of PA specimens. The presence of high-grade PA lesions was associated with HR acceleration after PADN (ρ = 0.68, p = 0.03). No significant correlation was found between the grade of PA lesion severity and PA pressure after PADN with or without PH induction., Conclusions: Extended PADN does not affect PH induction using TXA2. Significant PA adventitia damage is associated with HR acceleration after PADN. Possible delayed effects of PADN on perivascular nerves and pulmonary hemodynamics require further research in chronic experiments., (© 2021. The Author(s).)

Objective: We aimed to assess the effects of renal denervation (RDN) on systemic and pulmonary hemodynamics in a swine model of thromboxane A2- (TXA2-) induced pulmonary arterial hypertension (PAH)., Methods: The study protocol comprised two PAH inductions with a target mean pulmonary artery pressure (PAP) of 40 mmHg at baseline and following either the RDN or sham procedure. Ten Landrace pigs underwent the first PAH induction; then, nine animals were randomly allocated in 1 : 1 ratio to RDN or sham procedure; the second PAH induction was performed in eight animals (one animal died of pulmonary embolism during the first PAH induction, and one animal died after RDN). In the RDN group, ablation was performed in all available renal arteries, and balloon inflation within artery branches was performed in controls. An autopsy study of the renal arteries was performed., Results: At baseline, the target mean PAP was achieved in all animals with 25.0 [20.1; 25.2] mcg of TXA2. The second PAH induction required the same mean TXA2 dose and infusion time. There was no statistically significant difference in the mean PAP at second PAH induction between the groups (39.0 ± 5.3 vs. 39.75 ± 0.5 mmHg, P > 0.05). In the RDN group, the second PAH induction resulted in a numerical but insignificant trend toward a decrease in the mean systemic blood pressure and systemic vascular resistance, when compared with the baseline induction (74 ± 18.7 vs. 90.25 ± 28.1 mmHg and 1995.3 ± 494.3 vs. 2433.7 ± 1176.7  dyn ∗sec∗ cm -5 , P > 0.05, respectively). No difference in hemodynamic parameters was noted in the sham group between the first and second PAH induction. Autopsy demonstrated artery damage in both groups, but RDN resulted in more severe lesions., Conclusions: According to our results, RDN does not result in significant acute pulmonary or systemic hemodynamic changes in the TXA2-induced PAH model. The potential chronic effects of RDN on PAH require further research., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2021 Aleksandr D. Vakhrushev et al.)

Background: Pulmonary artery denervation (PADN) is an evolving interventional procedure capable to reduce pulmonary artery (PA) pressure. We aimed to compare PA nerve distribution in different specimens and assess the feasibility of an ovine model for a denervation procedure and evaluate the acute changes induced by laser energy., Methods: The experiment was divided into two phases: (1) the analysis of PA nerve distribution in sheep, pigs, and humans using histological and immunochemical methods; (2) fiberoptic PADN in sheep and postmortem laser lesion characteristics., Results: PA nerve density and distribution in sheep differ from humans, although pigs and sheep share similar characteristics, nerve fibers are observed in the media layer, adventitia, and perivascular tissue in sheep. Necrosis of the intima and focal hemorrhages within the media, adventitia, and perivascular adipose tissue were evidenced post laser PADN. Among the identified lesions, 40% reached adventitia and could be classified as effective for PADN. The use of 20 W ablation energy was safer and 30 W-ablation led to collateral organ damage., Conclusions: An ovine model is suitable for PADN procedures; however, nerve distribution in the PA bifurcation and main branches differ from human PA innervation. Laser ablation can be safely used for PADN procedures.

Transcatheter pulmonary artery denervation (PADN) has been developed for the correction of pulmonary hypertension. We investigated pulmonary artery stimulation mapping and its role in PADN procedures. Artery stimulation was performed in 17 Landrace pigs. Low-frequency stimulation defined areas of ventricular and atrial capture. High-frequency stimulation evoked the following responses: sinus rhythm slowing and/or atrial rhythm acceleration in 59% of animals, phrenic nerve capture in 100%, and laryngeal recurrent nerve capture in 23%. The sites with evoked heart rate responses were marked by discrete radiofrequency ablations (RFA). An autopsy showed nerves in the adventitia and perivascular fat under the RFA sites, and the lack of muscarinic-1, tyrosine hydroxylase, and dopamine-5 receptors' expression. During PADN, areas adjacent to the course of phrenic and recurrent laryngeal nerves should be avoided. RFA at points with heart rate responses leads to the non-reproducibility of evoked reactions and the disappearance of neural markers' expression. Graphical abstract.

U46619, a synthetic analogue of thromboxane A2 was used for modeling acute stable and reversible pulmonary arterial hypertension. Administration of U46619 in high doses led to vascular collapse and inhibition of cardiac function. The doses of U46619 were empirically selected that allow attaining the target level of pulmonary hypertension without systemic hemodynamic disturbances. The possibility of attaining the target level of pulmonary hypertension and reversibility of changes after termination of U46619 infusion make this model attractive for evaluation of the efficiency of different therapeutic methods of treatment of pulmonary hypertension in large animals.

For studying the possibility of using catheter denervation of the pulmonary artery for the treatment of pulmonary hypertension, large animals, such as pigs, are more suitable, because the diameter of the pulmonary artery in this case allows manipulation of the ablation catheter. The study of the perivascular adipose tissue of the trunk and bifurcation of the pulmonary artery in humans and pigs revealed differences in the density and diameter of nerve fibers, but their depth did not differ. Immunohistochemical analysis with different markers of the autonomic nervous system receptors revealed similar receptor profile in human and pigs, though the expression of all studied markers in pigs was less pronounced than in humans. These findings attest to similarity of the innervation of the pulmonary arteries in humans and pigs under normal conditions.

Objectives: We sought to assess acute changes in systemic and pulmonary hemodynamics and microscopic artery lesions following extended renal artery denervation (RDN)., Background: RDN has been proposed to reduce sympathetic nervous system hyperactivation. Although the effects of RDN on systemic circulation and overall sympathetic activity have been studied, data on the impact of RDN on pulmonary hemodynamics is lacking., Methods: The study comprised 13 normotensive Landrace pigs. After randomization, 7 animals were allocated to the group of bilateral RDN and 6 animals to the group of a sham procedure (SHAM). Hemodynamic measures, cannulation, and balloon-based occlusion of the renal arteries were performed in both groups. In the RDN group, radiofrequency ablation was performed in all available arteries and their segments. An autopsy study of the renal arteries was carried out in both groups., Results: The analysis was performed on 12 pigs (6 in either group) since pulmonary thromboembolism occurred in one case. A statistically significant drop in the mean diastolic pulmonary artery pressure (PAP) was detected in the RDN group when compared with the SHAM group (change by 13.0 ± 4.4 and 10.0 ± 3.0 mmHg, correspondingly; P = 0.04). In 5 out of 6 pigs in the RDN group, a significant decrease in systemic systolic blood pressure was found, when compared with baseline (98.8 ± 17.8 vs. 90.2 ± 12.6 mmHg, P = 0.04), and a lower mean pulmonary vascular resistance (PVR) (291.0 ± 77.4 vs. 228.5 ± 63.8 dyn∗sec∗cm -5 , P = 0.03) after ablation was found. Artery dissections were found in both groups, with prevalence in animals after RDN., Conclusions: Extensive RDN leads to a rapid and significant decrease in PAP. In the majority of cases, RDN is associated with an acute lowering of systolic blood pressure and PVR. Extended RDN is associated with artery wall lesions and thrombus formation underdiagnosed by angiography., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2020 Aleksandr D. Vakhrushev et al.)

Bioluminescent solid-phase analysis was proposed to monitor the selection process and to determine binding characteristics of the aptamer-target complexes during design and development of the specific aptamers. The assay involves Ca 2+ -regulated photoprotein obelin as a simple, sensitive and fast reporter. Applicability and the prospects of the approach were exemplified by identification of DNA aptamers to cardiac troponin I, a highly specific early biomarker for acute myocardial infarction. Two structurally different aptamers specific to various epitopes of troponin I were obtained and then tested in a model bioluminescent assay., (© 2020 American Society for Photobiology.)

Aim To present an own experience in using a medication selexipag in patients with pulmonary arterial hypertension (PAH) included into the V. A. Almazov National Medical Research Center registry and participating in the GRIPHON and GRIPHON OL clinical studies.Material and methods 26 patients with PAH were included into this study since 2010: 20 patients with idiopathic PAH, 4 patients with PAH associated with systemic scleroderma, and 2 patients with corrected congenital heart defects. At the time of randomization, 19 patients had been receiving therapy with phosphodiesterase type 5 inhibitors for at least one month. Among the patients treated with selexipag (n=14), 4 patients reached a high individual maintenance dose (1200-1600 µg b.i.d.), 4 patients reached a medium dose (600-1000 µg b.i.d.), and 6 patients reached a low dose (200-400 µg b.i.d.).Results The selexipag therapy exerted a positive effect on secondary endpoints, specifically, on changes in the functional class of pulmonary hypertension, serum concentration of NT-proBNP, and physical working capacity of patients. Adverse events associated with the selexipag treatment, which resulted in termination of study participation, were observed in one patient.Conclusion To achieve the main goal of drug therapy, low risk of death with selexipag it is critical to observe the titration schedule and to aim at reaching the highest individual maintenance dose.

Background: Recently, transcatheter pulmonary artery (PA) ablation aiming at sympathetic denervation has been proposed in pulmonary arterial hypertension (PAH). This pilot feasibility study aimed to assess the feasibility of selective radiofrequency PA ablation based on response to high-frequency stimulation mapping., Methods: The study comprised 3 female patients with idiopathic PAH (IPAH). The following reactions to PA stimulation were noted and marked by color points on the three-dimensional map: sinus bradycardia (heart rate decrease ≥15%), tachycardia (heart rate increase ≥15%), phrenic nerve capture, and cough. Since the most appropriate ablation strategy was unknown, two approaches were suggested, according to stimulation results: ablation at points with any heart rate response (either bradycardia or tachycardia)-this approach was applied in patient #1 (IPAH long-term responder to calcium channel blockers); segmental ablation at points with no response and with tachycardia response (one IPAH long-term responder to calcium channel blockers patient and one-IPAH with negative vasoreactive testing). Hemodynamic measurements were performed before and after denervation. Follow-up visits were scheduled at 6 and 12 months., Results: Six-months follow-up was uneventful for patients #1 and 3; patient #2 had one syncope and reduced 6-minute walk test distance and peak VO 2 consumption. At 12 months, there was a normalization of mean PA pressure and pulmonary vascular resistance (PVR) in patient #1. Patient #2 had no change in PA pressure and PVR at 12 months. Patient #3 remained in II functional class; however, there was an increase in mean PA pressure and loss of vasoreactivity., Conclusions: Electrical high-frequency stimulation of the PA identifies several types of evoked reactions: heart rate slowing, acceleration, phrenic nerve capture, and cough. The improvement in clinical and hemodynamic parameters following targeted PA ablation in the IPAH patient with positive vasoreactive testing should be confirmed in larger studies., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2020 Natalia S. Goncharova et al.)

Takayasu arteritis is well-known rare form of large vessel vasculitis. Pulmonary involvement is observed in 50% of cases. However, pulmonary hypertension is a rare complication of pulmonary artery stenosis. In this article we present a rare clinical case of Takayasus arteritis with typical stenosis of subclavian, carotid arteries, and involvement of pulmonary arteries with development of severe pulmonary hypertension. The article also contains discussion of current methods of diagnosis and treatment of pulmonary artery stenosis in Takayasus arteritis with special focus on effectiveness and complications of angioplasty and surgery.

Aim: To assess concentration of metalloproteinase (MMP) -9 and its inhibitor in blood serum of patients with defects of left cardiac chambers, associated with pressure or volume overload., Results: Elevation of MMP-9/TIMP-1 ratio at the account of MMP-9 was characteristic for patients with volume overload while elevation of blood serum level of TIMP-1 was characteristic for patients with pressure overload. MMP-9/TIMP-1 coefficient was directly related to left ventricular myocardial mass index and negatively related to myocardial contractile capacity. In patients with aortic stenosis elevation of TIMP-1 content was associated with lowering of global left ventricular contractility. Concentration of MMP-9 in blood serum and MMP-9/TIMP-1 ratio depended on etiology of valvular heart disease. Values of the given parameters were maximal in patients with mesenchymal dysplasia and sclerodegenerative calcinosis of the aortic valve., Conclusion: Serum levels of MMP-9 and TIMP-1, as well as MMP-9/TIMP-1 ratio reflect type and severity of hypertrophy of the myocardium and can be looked upon as markers of myocardial remodeling.

A system of crossing of 2 biotypes of cholera strains and nonagglutinating vibrios was worked out by means of modified Parker and Romig's method. The most frequent inheritance of the sex factor was noted in conjugation of strains belonging to the classic biotype. Inheritance of chromosomal genes (pur) was less incident. Sex pili 9 to 10 nm in diameter were revealed in donor V. cholerae 569 (B) P+ strain.

Hemolysin hyper- hypoproductive Vibrio eltor mutants and hemolytically inactive clones were isolated using tetracycline (Tn10) and chloramphenicol (Tn9) resistance transposons. Chromosomal localization was demonstrated for hml gene(s) involved in hemolysin production. Mutations responsible for an altered hemolysin production are likely to be situated closely to pur ura arg met chromosomal markers.

The specificity of integration of chloramphenicol resistance transposon (Tn9) into Vibrio El Tor chromosome was studied. As shown by the isolation of auxotrophs offerring various nitritional requirements, Tn9 displayed fairly low specificity in its interaction with the chromosome. When inserted into cholera vibrio chromosome, Tn9 induced secondary rearrangements of genetic material. Nutritional requirements were identified for the polyauxotrophic clones which resulted from the mutations in chromosome region adjacent to the insertion sites of Tn9 and Tn10. Based on these observations a preliminary map was constructed for certain regions of V. eltor chromosome.

Introduction of tetracycline-resistance transposon Tn10 into Rts1 (Km), a plasmid which is temperature-sensitive for DNA replication, made it possible to construct pNS10 (Km Tc) plasmid used as a vehicle for transferring Tn10 from Escherichia coli to cholera vibrio V. El Tor 218 as a result of intergeneric crosses. While being translocated from the plasmid genome to the chromosome of cholera vibrio transconjugants, Tn10 was able of insertion into structural genes thus leading to the formation of auxotrophic mutants. Ability of Tn10 to promote chromosomal rearrangements of the regions linked to Tn-element insertion site was used for identification of some structural genes in the neighbourhood of Tn-element insertion site.

There proved to be a serological similarity between the antigens of the human small intestine, the stomach and the liver, and the antigens of various cholera vibrio fractions. No antigenic similarity was revealed in examination of the heart and kidney. Heterogenous antigen was found not only in the somatic V. cholerae antigen, strain 569 (B), but also in the cholerogen-toxoid obtained from it. At present it is the most widespread prophylactic preparation.