Using multilayer polymer PI/Pb composites for protection against X-ray bremsstrahlung in outer space

This paper presents data about the radiation-protective characteristics of multilayer polyimide/lead (PI/Pb) composites for X-ray radiation. Multilayer composites were obtained by collecting lead-filled polyimide track membranes into a sandwich of the required thicknes

Comparative efficacy and safety of mycophenolate mofetil and azathioprine in combination with corticosteroids in the treatment of lymphocytic myocarditis

Aim. To study the efficacy and safety of mycophenolate mofetil (MM) in combination with corticosteroids in the treatment of lymphocytic myocarditis in comparison with a standard combination of corticosteroids and azathioprine.Material and methods. The study included 46 patients aged 18 years and older with severe and moderate lymphocytic myocarditis (men, 34; women 12; mean age, 53,5±13,0 years). The diagnosis was verified using endomyocardial biopsy. Symptom duration averaged 9,5 [4; 20.25] months. All patients had class 3 [2,75; 3] heart failure (HF). The main group included 29 patients who received MM 2 g/day, including six patients — instead of azathioprine, which was canceled due to cytopenia (n=3) or insufficient effect (n=3). The comparison group included 17 patients who received azathioprine 150 [100; 150] mg/day. Patients of both groups also received methylprednisolone at a starting dose of 24 [24; 32] and 24 [24; 24] mg/day and standard HF therapy. In 7/2 patients, the parvovirus B19 genome was detected in the myocardium. In all cases, an increase in anticardiac antibody titers was evidence of immune activity. The average follow-up period was 24 [12; 54] months (at least 6 months).Results. The groups were completely comparable in age, initial characteristics and standard drug therapy. In both groups, a comparable significant increase in the ejection fraction (EF) was noted as follows: from 31,2±7,6 to 44,7±8,3% and from 29±9,1 to 46±11,9% (p<0,001). An excellent response to treatment (an increase in EF by 10% or more) was noted in 68,2% and 66,7% of patients, a good response (by 9-5%) — in 27,3% and 14,3%, a poor response (an increase in less than 5% or a decrease in EF) — in 4,5% and 19,0%, respectively. In both groups, we noted the same significant (p<0,01) decrease in pulmonary artery systolic pressure (36,3±12 to 28,1±6,1 mm Hg in the MM group and from 44,1±8,5 to 30,7±12,1 mm Hg in the azathioprine group), left ventricular (LV) end-diastolic dimension (from 6,4±0,6 to 6±0,7 cm and from 6,2±0,5 to 5,8±0,6 cm), LV end-diastolic volume (from 188,7±55,2 to 178,8±57,1 ml and from 167,8±47,5 to 163,3±61,8 ml), LV end-systolic volume (from 130,3±44,1 to 98,4±32 ml and from 118,1±39 to 94,1±46 ml), left atrial volume (from 98,3±30,3 to 86,7±32,6 ml and from 105±27,4 to 91,2±47,3 ml, p<0,05), as well as mitral regurgitation grade. The incidence of deaths was 2 (6,9%) and 2 (8,7%), transplantation — 1 (3,4%) and 1 (4,3%) patients, death+transplantation end point — 3 (10,3%) and 2 (11,8%) without significant differences between the groups. The presence of the parvovirus B19 genome did not affect the results of treatment. The incidence of infectious complications was comparable in both groups (in one case, MM was completely canceled), no new cytopenia cases were noted during the follow-up period.Conclusion. In patients with moderate and severe virus-negative (except for parvovirus B19) lymphocytic myocarditis, the combination of moderate-dose corticosteroids with mycophenolate mofetil 2 g/day is at least no less effective than the standard regimen of immunosuppressive therapy. There was a tendency towards a more pronounced decrease in anticardiac antibody titers in combination with better tolerance (no cases of cytopenia) in MM group. MM in combination with corticosteroids can be recommended as an alternative treatment regimen for lymphocytic myocarditis

Infective and nonbacterial thrombotic endocarditis in patients with post-COVID-19 viral-immune myocarditis

The possibility of heart inflammation (both myocardial and endocardial) months after a coronavirus disease 2019 (COVID-19) has not been practically studied, especially since approaches to the treatment of myocarditis in combination with various endocarditis forms have not been developed.Aim. To study the prevalence and mechanisms of SARS-CoV-2-associated endocardial injury in patients with morphologically verified post-COVID-19 myocarditis, as well as to develop approaches to comprehensive therapy.Material and methods. The study included 18 patients with severe morphologically verified post-COVID-19 myocarditis (men, 9; 51,1±9,4 years; 35 to 66 years). Patients with prior verified myocarditis/myocardial infarction, rheumatic heart disease, and systemic immune diseases were excluded. The average time after COVID-19 was 6,5 [3.5; 10] months The diagnosis of myocarditis was confirmed by endomyocardial biopsy (including immunohistochemical examination with antibodies to CD3, CD20, CD45, CD68, and to SARS-CoV-2 antigens; polymerase chain reaction for SARS-CoV-2 RNA, DNA of cardiotropic viruses). The blood level of anticardiac antibodies was determined by indirect immunofluorescence. In addition, echocardiography, magnetic resonance imaging (n=8), cardiac multislice tomography (n=1), and coronary angiography (n=14) were performed.Results. Biopsy revealed active (n=12) and borderline (n=3) lymphocytic myocarditis, eosinophilic (n=2) and giant cell (n=1) myocarditis. In 4 patients, nonbacterial thrombotic endocarditis (NBTE) with parietal and intravascular thrombosis was diagnosed, and in one patient — infective endocarditis (IE) of the bicuspid aortic valve. Myocardial persistence of SARS-CoV-2 was detected in 72% of cases (in 3 patients — with NBTE; in 1 — with IE; in 9 — without endocarditis). Titers of anticardiac antibodies increased by 3-4 times in 94% of patients. Patients with endocarditis were characterized by larger heart chambers, lower ejection fraction (27,5±6,6 vs 36,0±13,4%), more severe pulmonary hypertension, and valvular regurgitation. Intraventricular thrombosis according to echocardiography/magnetic resonance imaging and cardiac embolism was not observed. Treatment in all patients included methylprednisolone at an average dose of 24 mg a day. In 10 patients, the result was monitored for at least 3 months as follows: the ejection fraction was 46,0±12,7% and 44,3±7,3% in patients with and without endocarditis, respectively.Conclusion. Endocarditis in patients with post-COVID-19 myocarditis was detected in 28% (1 patient — IE; 4 — NBTE). The key mechanisms of post-COVID-19 myocarditis and NBTE are long-term (up to 18 months) myocardial persistence of SARS-Cov-2 and the development of an autoimmune reaction. Endocarditis was diagnosed in more severe patients, including those with giant cell and eosinophilic myocarditis. The effectiveness of steroid therapy in combination with anticoagulants in patients with NBTE requires further study. In case of IE, steroids can also be used in the treatment of myocarditis (in combination with antibiotics and immunoglobulin)