Activation of Cardiac δ2-Opioid Receptors Increases Heart Tolerance to Reperfusion.

Coronary occlusion (45 min) and reperfusion (120 min) in male Wistar rats in vivo, as well as total ischemia (45 min) of an isolated rat heart followed by reperfusion (30 min) were reproduced. The selective δ2-opioid receptor agonist deltorphin II (0.12 mg/kg and 152 nmol/liter) was administered intravenously 5 min before reperfusion in vivo or added to the perfusion solution at the beginning of reperfusion of the isolated heart. The peripheral opioid receptor antagonist naloxone methiodide and δ2-opioid receptor antagonist naltriben were used in doses of 5 and 0.3 mg/kg, respectively. It was found that the infarct-limiting effect of deltorphin II is associated with the activation of δ2-opioid receptors. We have demonstrated that deltorphin II can improve the recovery of the contractility of the isolated heart after total ischemia.

The Role of δ2-Opioid Receptors in the Regulation of Tolerance of Isolated Cardiomyocytes to Hypoxia and Reoxygenation.

Hypoxia (20 min) and reoxygenation (30 min) were simulated on isolated rat cardiomyocytes to evaluate the cytoprotective effect of selective δ2-opioid receptor agonist deltorphin II, opioid receptor antagonist naloxone methiodide, µ-opioid receptor antagonist CTAP, κ-opioid receptor antagonist nor-binaltorphimine, ε1-opioid receptor antagonist BNTX, and δ2-opioid receptors naltriben. Deltorphin II was administered 5 min before reoxygenation, antagonists were administered 10 min before reoxygenation. The cytoprotective effect of deltorphin II was assessed by the number of cardiomyocytes survived after hypoxia/reoxygenation, as well as by the lactate dehydrogenase content in the incubation medium. It has been established that the cytoprotective effect of deltorphin II occurs at a concentration of 64 nmol/liter and is associated with activation of δ2-opioid receptors.

Comparative Analysis of Infarct-Limiting Activity of Peptide and Non-Peptide δ- and κ-Opioid Receptor Agonists during Heart Reperfusion In Vivo.

A comparative analysis of the infarct-limiting activity of δ- and κ-opioid receptors (OR) agonists was carried out on a model of coronary occlusion (45 min) and reperfusion (120 min) in male Wistar rats. We used selective δ2-OR agonist deltorphin II (0.12 mg/kg), δ-OR agonists BW373U86 and p-Cl-Phe DPDPE (0.1 and 1 mg/kg), selective agonists of δ1-OR DPDPE (0.1 and 0.969 mg/kg), κ1-OR U-50,488 (0.1 and 1 mg/kg), κ2-OR GR-89696 (0.1 mg/kg), and κ-OR ICI-199,441 (0.1 mg/kg). All drugs were administered intravenously 5 min before reperfusion. Deltorphin II, BW373U86 (1 mg/kg), p-Cl-Phe DPDPE (1 mg/kg), U-50,488 (1 mg/kg), and ICI-199,441 had a cardioprotective effect. The most promising compounds for drug development are ICI-199,441 and deltorphin II.

[Features of the intestinal microbiota in the elderly in the development of coronary heart disease.]

The review is devoted to the influence of the microbiota on the development of such an age-dependent disease as coronary heart disease, the formation of which depends on atherogenesis in particular. According to the World Health Organization, cardiovascular disease is the leading cause of death worldwide. Statistical data from the Federal State Statistics Service also confirm that coronary heart disease is the leading cause of death in the Russian Federation today. It is known that the vast majority of cardiovascular diseases are atherosclerosis-associated pathologies. Atherogenesis and the state of the human gut microbiome are dynamically interrelated. The gut microbiota, which consists predominantly of bacteria, plays an important role in maintaining homeostasis. The pathogenesis of atherosclerosis is based on systemic inflammation. Aging is accompanied by a wide variety of clinical manifestations, including a basic pro-inflammatory state (i.e., «inflammation-aging¼), the activity of which is maintained by the microbiota in older individuals and increases their susceptibility to diseases. Intestinal microbiocenosis in elderly and senile people differs from those of young people. In persons of older age groups, there is an increase in microorganisms secreting endotoxins lipopolysaccharide and trimethylamine-n-oxide, initiating and maintaining chronic inflammation. More research is needed to study the mechanisms of action of microbial metabolites and their clinical application in various therapeutic interventions.

Role of PI3K, ERK1/2, and JAK2 Kinases in the Cardioprotective Effect of Deltorphin II during Cardiac Reperfusion.

The signaling mechanism of the cardioprotective effect of deltorphin II was studied in models of coronary occlusion (45 min) and reperfusion (120 min) in male Wistar rats. We used the selective δ2-opioid receptor agonist deltorphin II (0.12 mg/kg), which was administered intravenously 5 min before reperfusion, the PI3K inhibitor wortmannin (0.025 mg/kg), the ERK1/2 blocker PD-098059 (0.5 mg/kg), the inhibitor JAK2 AG490 (3 mg/kg). All kinase blockers were administered 10 min before reperfusion. The infarct-limiting effect of deltorphin II is associated with the activation of PI3K and ERK1/2 and does not depend on JAK2.

The Role of NO Synthase, MPT pore, and Protein Kinase A in the Cardioprotective Effect of the Opioid Receptor Agonist Deltorphin II.

In male Wistar rats, coronary occlusion (45 min) and reperfusion (120 min) were modeled. Selective δ2-opioid receptor agonist (deltorphin II, 0.12 mg/kg) was administered intravenously 5 min before reperfusion; NO synthase inhibitor (L-NAME, 10 mg/kg), MPT pore blocker (atractyloside, 5 mg/kg), and protein kinase A inhibitor (H-89, 10 µg/kg) were administered intravenously 10 min before reperfusion. Deltorphin II administered before reperfusion led to a 2-fold decrease in the infarct size. The infarct-limiting effect of deltorphin II was associated with blockade of MPT pore. Protein kinase A and NO synthase were not involved in the cardioprotective effect of deltorphin II.

Interstitial Edema of the Interatrial Septum in Patients with Atrial Fibrillation and Chronic Heart Failure.

We studied the presence of interstitial edema of the interatrial septum in patients with chronic heart failure (CHF) with atrial fibrillation (n=23) or without rhythm disturbances (n=9). The intensity of the MRI signal of the interatrial septum, interventricular septum, and skeletal muscle by T2-weighted MRI and the enhancement index of interatrial septum (the ratio of the signal intensity of the interatrial septum to the signal intensity of the skeletal muscle) were evaluated. The enhancement index of interatrial septum ⩾2 was regarded as an MRI sign of myocardial edema. The enhancement index of interatrial septum in patients with persistent atrial fibrillation was 2.4 (2.21; 2.69) and was higher than in CHF patients with paroxysmal atrial fibrillation and in CHF patients without arrhythmias and surpassed the control values (p<0.05), which indicates the presence of MRI signs of edema of the myocardium of the interatrial septum. The obtained data confirm the presence of myocardial edema of the interatrial septum in CHF patients and persistent form of atrial fibrillation, which expands the understanding of the pathogenesis of this condition.

Effect of the "door-to-balloon" time on the results of treatment of patients with ST-segment elevation myocardial infarction, depending on the duration of the pre-hospital delay.

Aim    To analyze the effect of the door-to-balloon time on treatment outcomes in patients with acute ST-segment elevation myocardial infarction (STEMI) depending on the duration of pre-hospital delay.Material ad methods    The study used data of the hospital registry of percutaneous coronary interventions (PCI) in STEMI from 2006 through 2017. The analysis included 1333 patients. All patients were divided into two groups. The first group included 574 (43.1%) patients with the time from the pain syndrome onset to admission was ≤120 min. The second group consisted of 759 (56.9 %) patients with the time of pre-hospital delay exceeding 120 min. Results of the treatment were analyzed for each group depending on the door-to-balloon time, ≤60 min or >60 min.Results    In the group of patients with the prehospital delay less than 120 min and the door-to-balloon time ≤60 min vs. patients with the door-to-balloon time >60 min, the following was observed: decreased in-hospital mortality (1.3 % vs. 6.8 %, p=0.001), reduced incidence of major adverse cardiac effects (МАСЕ) (3.2 % vs. 8.3 %, p=0.008), and reduced incidence of the no-reflow phenomenon (3.9 % vs. 9.4 %, p=0.007). Also, immediate angiographic success of PCI was more frequently achieved in these patents (94.5 % vs. 87.5 %, p=0.003). In addition, in the group with the prehospital delay ≤120 min and the door-to-balloon time ≤60 min, a higher ejection fraction was noted at discharge from the hospital (48 [43; 51] % vs. 46 [42; 51] %, р=0.038). Comparison of treatment outcomes between the groups with different door-to-balloon time (≤60 min or >60 min) and a prehospital delay >120 min did not show any significant intergroup differences. According to a multivariate analysis, the door-to-balloon time ≤60 min did not predict in-hospital mortality. There was a strong correlation between the time of prehospital delay and the total time of myocardial ischemia (r=0.87; р<0.001) while the correlation between the door-to-balloon time and the total time of myocardial ischemia was moderate (r=0.41; р<0.001). At the same time, there was no correlation between the time of prehospital delay and the door-to-balloon time.Conclusion    In STEMI patients with a prehospital delay less than 120 min from the pain syndrome onset, a decrease in the door-to-balloon time was associated with better outcome of the hospital treatment. When the duration of prehospital delay was more than 120 min, a decrease in door-to-balloon time did not influence the treatment outcome. The time of prehospital delay strongly correlated with the total time of myocardial ischemia.

[Modern aspects of diagnostics and treatment of renal infarction].

One of the causes of acute kidney injury is the renal artery thrombosis. Clinical manifestations depend on the level of thrombus. This pathology is characterized by non-specific clinical manifestations in the early period, the complexity of differential diagnosis, often delayed verification of the diagnosis and unfavorable prognosis in case of prolonged (5-7 days) anuria. There is no generally accepted protocol for the diagnosis and treatment of renal artery thrombosis. To clarify the diagnosis, intravenous urography, radionuclide renography, and contrast-enhanced computed tomography are recommended. Until recently, patients with suspected renal artery thrombosis were treated with anticoagulant therapy and renal replacement therapy with hemodialysis, which is required constantly as renal function was usually irreversibly impaired. Surgical treatment is effective only in the first hours. The outcome is often unfavorable, the probability of hemorrhagic complications is high. Due to the rare frequency of detection and verification of renal infarction, no consensus has been reached regarding the diagnosis or treatment of this condition.

[Non-ischemic priapism (post-traumatic arteriovenous fistula of the right cavernous body) in the background of Landusy-Dejerine myopathy].

Landouzy-Dejerine myopathy (Facial-shoulder-shoulder myodystrophy) is a disease which causes weakness of the muscles of the shoulder girdle, back and hip muscles, which predisposes patients to an increased risk of injury and disability. The article presents a clinical observation of non-ischemic priapism, which developed as a result of perineal trauma with the formation of a fistula of the right cavernous body in a patient against the background of facial shoulder-shoulder myodystrophy. Methods for the differential diagnosis of this condition are also discussed.

[Enoxaparin sodium for pharmacological prevention of postoperative venous thromboembolic complications in urological patients].

INTRODUCTION: Currently, there are paucity of reports on the success of medical prevention of venous thromboembolic complications after urological procedures. AIM: To evaluate the efficiency of enoxaparin sodium for prevention of postoperative venous thromboembolic complications in urological patients. MATERIALS AND METHODS: According to the medical records of 151 men and women aged 22 to 92 years old who were undergone to elective surgical treatment in April 2021, the results of the thrombin generation assay and ultrasound study of the inferior vena cava were retrospectively analyzed. All patients were divided into 6 study groups depending on the degree of risk of postoperative venous thromboembolism (very low, low, moderate, high, very high and extremely high). The data obtained during the thrombin generation assay in patients from different groups were compared with those in healthy volunteers (n=30, control group) and evaluated in dynamics. In addition, intergroup comparison was done. RESULTS: All study participants prior to surgery had a significant increase in peak thrombin and endogenous thrombin potential (ETP) by 5-26% and 13.5-21.5%, respectively. The postoperative findings were as following: 1) one hour after the procedure, a significant (by 9-28.6%) decrease in the normal bleeding time (Lag time); 2) a significant increase in the peak thrombin by 4.8-10.6% 1 hour after surgery and by 11-40.2% at the end of the first postoperative week; 3) reducing the time to peak thrombin (ttPeak) by 13-15%; 4) increase in ETP. According to the ultrasonic data, all study participants had no signs of thrombosis of the inferior vena cava system. CONCLUSION: In urological patients requiring surgical treatment, before and after procedure, there is almost always a shift in the hemostasis towards the predominance of the blood coagulation system. Under such conditions, to prevent the development of postoperative VTE, it is expedient and pathogenetically justified to use enoxaparin sodium in a single dose of 0.4 ml or 4000 anti-Xa IU administered once a day s/c 24 hours before the procedure and till full activation of a patient.

[Gastroprotective and antidepressant-like effect of plum pectin (Prunus domestica L.) under water-immobilization stress in laboratory mice].

Stress effects activate the processes of free radical oxidation in the organism, lead to hyper production of reactive radicals and oxidative stress, provoking the development of an inflammatory process in various parts of the gastrointestinal tract. Pectin polysaccharides together with the enzyme components of the endogenous antioxidant system contribute to the elimination of the imbalance between prooxidants and antioxidants in the tissues of stressed animals and have a gastroprotective and antidepressant-like effect. The aim of the research was to evaluate the gastroprotective, antioxidant and antidepressant-like effect of plum pectin orally administered to white laboratory mice before stressful exposure. Material and methods. In the experiment on white BALB/c mice weighing 20-25 g (90 males, 10 in each group), pectin isolated from fresh plum fruits in an artificial gastric environment was used. It was administered orally to mice 24 h before the onset of stress exposure or behavioral activity asessment. 50 animals were subjected to 5 h of water immersion stress. After this corticosterone concentration in blood plasma, and the activity of superoxide dismutase, catalase and glutathione peroxidase in the tissue supernatants of the gastrointestinal tract were determined, and the condition of the gastric mucosa was also assessed. Behavioral activity of experimental mice (n=30) was assessed in the open field and forced swimming tests. Results. The stress effect was accompanied by an increase in plasma corticosterone concentration (more than 3 fold), in the activity of superoxide dismutase, glutathione peroxidase in the tissues of the stomach wall and small intestine (17.9-28.6%) and destructive damage in the gastric mucosa compared with the indices of intact animals. Preliminary oral administration of plum pectin to animals at a dose of 80 mg per 1 kg of body weight helped to reduce the level of corticosterone and the number of stress-induced hemorrhages on the gastric mucosa, normalized the activity of antioxidant enzymes and also decreased the immobility time of mice in the forced swimming test. Preliminary oral administration of plum pectin to animals at a dose of 80 mg per 1 kg of body weight prevented an increase in the activity of antioxidant enzymes, corticosterone in the blood and the development of stress-induced hemorrhages on the gastric mucosa, and reduced the time of immobility of mice in the forced swimming test. Conclusion. Plum fruit pectin pre-administered into mice before stress prevents stress-induced damage in the tissues of the gastrointestinal tract, contributing to an increase in the body's resistance to the stress factor. Plum pectin has an antioxidant, gastroprotective and antidepressant-like effect and can be used as an ingredient in functional foods that reduce the risk of inflammatory diseases of the gastrointestinal tract under stress.

[High-tone therapy in complex rehabilitation of patients with post-sternotomy syndrome after coronary artery bypass surgery. (Open-label, prospective, randomized controlled trial)]. / Vysokotonovaya terapiya v kompleksnoi reabilitatsii bol'nykh s poststernotomicheskim sindromom posle aortokoronarnogo shuntirovaniya. (Otkrytoe prospektivnoe randomizirovannoe kontroliruemoe issledovanie).

INTRODUCTION: At present it remains relevant to develop new rehabilitation technologies for patients with circulatory system diseases who have undergone a cardiac surgery to restore the functions of the cardiorespiratory system more quickly, improve physical and mental health, and prevent the development of the atherosclerotic process. AIM: To study the effectiveness and safety of the new rehabilitation technology for the inpatient stage of medical rehabilitation of patients with post-sternotomy syndrome after coronary artery bypass surgery (CABS) using high-tone therapy. MATERIAL AND METHODS: The study included 85 men (the average age was 56.8±2.46 years old) with post-sternotomy syndrome after CABS. They were divided into two groups by simple randomization: the first/main (42 patients) and the second/control (43 patients). The control group of the patients had a standard rehabilitation complex; the main group was additionally prescribed a high-tone therapy according to a local method. The immediate results of the treatment were assessed by the dynamics of the clinical picture, the six-minute walk test, respiratory function, echocardiography, the level of cytokines, C-reactive protein and natriuretic peptide (NT-proBNP); distant - by QOL endpoints (questionnaire MOS SF-36). RESULTS: The groups of the patients were comparable in all baseline parameters. After the course of the procedures in the main group of patients there were positive reliable (p<0.05-0.001) shifts in clinical (pain, shortness of breath, general weakness), functional (forced expiratory vital capacity, forced expiratory volume1, effusion separation) and laboratory parameters (leukocytes, interleukin-2 and 10, NT-proBNP). The intergroup analysis of long-term results registered significant (p<0.05) differences in the QOL of patients in the main group by subscales: the role of somatic problems, vitality and mental health. Compliance to the III stage of medical rehabilitation (outpatient/home) was noted with 95.2% of the patients in the first group and 93.0% in the second. CONCLUSION: The additional appointment of a high-tone therapy to the rehabilitation standard for the patients with post-sternotomy syndrome after CABS significantly improves the immediate and long-term results of the treatment (QOL) contributing to a more pronounced reverse development of inflammatory and edematous syndromes, an increase in physical activity and psychosomatic health. The absence of adverse reactions with all the patients indicates the safety of rehabilitation complexes.

Cardiac 123I-mIBG scintigraphy for prediction of catheter ablation outcome in patients with atrial fibrillation.

BACKGROUND: Previous studies show inconsistent results on the role of innervation imaging (with 123I-mIBG) in predicting late atrial fibrillation (AF) recurrence after catheter ablation (CA). These studies included patients with paroxysmal AF and studied prognostic value of post-CA I-123-mIBG parameters. Current study investigated the ability of pre CA 123-I-mIBG imaging to predict late AF recurrence in patients with persistent AF. METHODS: 123I-mIBG cardiac imaging was performed before CA in 82 patients with persistent AF. Patient was followed for 12 months. RESULTS: Multivariable analysis demonstrated that late heart-to-mediastinum ratio (H/Mlate) and washout rate (WR) were independent predictors of AF recurrence. ROC-curve analysis data showed that H/Mlate <1.6 (sensitivity 73.53%, specificity 81.3%, AUC 0.792, P < .001) and WR > 25.11 (sensitivity 70.6%, specificity 70.8.3%, AUC 0.712, P < .001) indicate high probability of AF relapses during 12 months after CA. CONCLUSION: Pre-CA parameters of global cardiac sympathetic activity estimated by 123I-mIBG scintigraphy are associated with late AF relapses in persistent AF patients with normal LVEF and absence of significant CAD.

1-benzoyl-6-hydroxy-2,2,4-trimethyl-1,2-dihydroquinoline exerts a neuroprotective effect and normalises redox homeostasis in a rat model of cerebral ischemia/reperfusion.

Ischemia is one of the main etiological factors of stroke and is associated with the development of energy deficiency, oxidative stress, and inflammation. An abrupt restoration of blood flow, called reperfusion, can worsen the effects of ischemia. In our study, we assessed the neuroprotective potential of 1-benzoyl-6-hydroxy-2,2,4-trimethyl-1,2-dihydroquinoline (BHDQ) in cerebral ischemia/reperfusion (CIR) in rats. Wistar rats, divided into 4 groups were used in the study: sham-operated animals; animals with CIR caused by occlusion of the common carotid arteries and subsequent removal of the occlusions; rats treated with BHDQ at a dose of 50 mg/kg in the presence of pathology; sham-operated animals treated with BHDQ. The analysis of the state of energy metabolism in the brain, the level of the S100B protein and the histological assessment of the brain tissue were carried out. The antioxidant potential of BHDQ was assessed by measuring biochemiluminescence parameters, analysing the level of 8-isoprostane, products of lipid and protein oxidation, concentration of α-tocopherol and citrate, and aconitate hydratase activity during CIR in rats. A study of the effect of BHDQ on the regulation of the enzymatic antioxidant system and the inflammatory processes was performed. We demonstrated that BHDQ has a neuroprotective effect in CIR, reducing histopathological changes in the brain, normalizing pyruvate and lactate concentrations, and the transcripts level of Hif-1α gene. The positive effect of BHDQ was probably due to its antioxidant and anti-inflammatory activity, manifested in a decrease in the parameters of the oxidative stress, decreased mRNA of proinflammatory cytokines and NF-κB factor genes. In addition, BHDQ reduced the load on antioxidant protection enzymes, contributing to a change in their activities, decreased the level of antioxidant gene transcripts and expression of Nrf2 and Foxo1 factors toward control. Thus, BHDQ exhibited a neuroprotective effect due to a decrease in the level of oxidative stress and inflammation and the normalization of redox homeostasis on CIR in rats.

Analgesic properties of the dry combined extract BNO 1016 in leukotriene depended hyperalgesia.

Combined dry extract BNO 1016 is a herbal drug commonly used for rhinosinusitis therapy. It is known that a significant role in rhinosinusitis pathogenesis is played by an inflammatory reaction in maxillary sinuses of the nasal cavity. At the initial stage of any inflammation the largest impact is caused by leukotrienes. Major chronic rhinosinusitis (CRS) according to the guideline EPOS-2020 include facial pain as clinical diagnostic criteria for rhinosinusitis. Therefore, it is reasonable to study the analgesic effects of the combined dry extract BNO 1016 on the model of zymozan- induced hyperalgesia. The tested drug is the combined dry extract BNO 1016 ("Bionorica SE", Germany) at different dose levels. The reference drug is ibuprofen. Leukotriene hyperalgesia was induced by subplantar injection of zymozan into the paw of Wistar rats. Pain threshold was evaluated with Ugo-Basil analgesimeter and analgesic activity was calculated together with mean effective dose (ED50) with help of the Probit Analysis. The highest analgesic activity was observed at a dose level of 500 mg/kg of BNO 1016 during all time-points of the experiment and reached 169.5% 3h after hyperalgesia onset. The analgesic activity of BNO 1016 at doses of 50 mg/kg in 1h, 2h, 3h after induction hyperalgesia, 150 mg/kg and 500 mg/ kg was credibly higher than that of Ibuprofen at all time-points of the experiment. Based on the experimental data, the index of ED50 for analgesic activity of BNO 1016 was calculated with Probit Analysis. The combined dry extract BNO 1016 shows a high level of analgesic activity in the leukotriene-depended hyperalgesia model, which is very promising for the improvement of treatment of patients with CRS, but additional preclinical and clinical researches are reasonable.

[Time perspective, sleep and wellbeing of the elderly during COVID-19 pandemic.]

The purpose of this study was to analyze the association between the time perspective and the psychophysiological state of the elderly during the pandemic COVID-19. 433 residents from 11 Russian cities aged 60,8±9,8 years (range - 50-94 years, women - 78,7%) took part in the study. During the online survey, each participant of the study provided personal data (place of residence, sex, age, height, and weight) and completed the Zimbardo Time Perspective Inventory, the Munich Chronotype Questionnaire, the Beck Depression Inventory and the Yale Food Addiction Scale. It was found that elderly people with a balanced time perspective had the lowest level of depression during the pandemic COVID-19 and less expressed sleep inertia at work days, while those with a past negative time perspective had the highest level of depression, high frequency of detection of food addiction and low sleep efficiency. The other types of time perspective (past positive, present hedonistic, present fatalistic and future) had intermediate values of indicators between these two extreme options. Thus, the conducted studies have shown that elderly people with a balanced time perspective showed the highest level of resistance to psychoemotional stress caused by the pandemic COVID-19.

δ2-Opioid Receptors as a Target in Designing New Cardioprotective Drugs: the Role of Protein Kinase C, AMPK, and Sarcolemmal KATP Channels.

In rats anesthetized with α-chloralose, coronary artery occlusion (45 min) and reperfusion (120 min) were modeled. The selective δ2-opioid receptor agonist deltorphin II was administered 5 min before reperfusion. Protein kinase C inhibitor chelerythrine, AMP-activated protein kinase inhibitor compound C, and ATP-sensitive K+ channel blockers glibenclamide, 5-hydroxydecanoate, and HMR 1098 were administered 10 min before reperfusion. It was found that the infarct-limiting effect of deltorphin II is associated with activation of protein kinase C and opening of sarcolemmal ATP-sensitive K+ channel.

Parameters of Oxidative Stress and Activity of Antioxidant Enzymes in the Saliva of Patients with Type 1 Diabetes Mellitus.

Glucose concentration in the saliva is increased in type 1 diabetes mellitus. This parameter directly correlates with markers of the disease in the blood serum. Increased concentration of 8-oxo-2'-deoxyguanosine (8-OHdG) and diene conjugates, markers of oxidative stress, and reduced activities of superoxide dismutase and catalase were also observed in this pathology. Correlation analysis revealed a strong positive correlation between glucose concentration and the levels of oxidative stress markers and a negative correlation between activity of antioxidant enzymes and glucose concentration. The results indicate that the level of 8-OHdG, diene conjugates, and superoxide dismutase and catalase activities can serve as diagnostic markers of pathophysiological changes in the body in type 1 diabetes mellitus.

[Complete atrioventricular block as the first manifestation of dermatomyositis].

Dermatomyositis is a rare systemic autoimmune disease characterized by primary damage of the skin and striated muscles with the development of chronic muscle weakness. Due to the polymorphic nature of the clinical picture, early diagnosis of dermatomyositis is challenging since patients may visit different specialists depending on predominating symptoms. This entails a late diagnosis and, as a result, the absence of necessary treatment. The article presents a clinical case of a late diagnosis of dermatomyositis, which resulted in the development of autoimmune myocarditis with complete atrioventricular block in a female patient.