[COVID-19 in haemodialysis patients: result analysis of the first year of the pandemic].

BACKGROUND: Present concepts of the novel coronavirus infection prognosis in haemodialysis (HD) patients are rather controversial. There is little information on therapy efficiency and safety in such patients. We studied COVID-19 course specifics, prognostic factors associated with fatal outcomes, therapy efficiency and its transformation at different stages of the pandemic first year. MATERIALS AND METHODS: Single-centre retrospective uncontrolled study included 653 COVID-19 HD-patients treated at Moscow City Nephrology Centre from April 1 to December 31, 2020. RESULTS: This period mortality rate was 21.0%. Independent predictors of COVID-19 unfavourable outcome in HD patients were pulmonary lesion extension (CT grades 34), high comorbidity index, and mechanical ventilation. Approaches to COVID-19 treatment modified significantly at different periods. Immunomodulatory drugs (monoclonal antibodies to IL-6, corticosteroids) were used largely at later stages. With tocilizumab administration, mortality was 15.1%, tocilizumab together with dexamethasone 13.3%; without them 37.8% (р0,001). Tocilizumab administration in the first 3 days after hospitalization of patients with CT grades 12 was associated with more favourable outcomes: 1 out of 29 died vs 6 out of 20 (tocilizumab administered at later periods); p0.04. There was no significant difference in death frequency in patients with CT grades 34 depending on tocilizumab administration time. CONCLUSION: COVID-19 in HD patients can manifest in a severe course with unfavourable outcome. It is urgent to identify reliable disease outcome predictors and develop efficient treatment in this population.

[A rare concurrence of polymyalgia rheumatica and AA-amyloidosis]. / Redkoe sochetanie revmaticheskoi polimialgii s AA-amiloidozom.

Polymyalgia rheumatica (PMR) is a rare chronic inflammatory disease. It predominantly affects the elderly. The disease has a slow onset, pain and stiffness in the muscles of the shoulder and pelvic girdle, fever, weight loss, and a high acute-phase inflammatory response. The disease is concurrent with giant cell arteritis in a quarter of cases, which allows some authors to consider them as two different manifestations of the same pathological process. The kidneys are rarely involved. This disease is rarely complicated by AA amyloidosis. The authors describe a case of RPM in a patient who has developed secondary AA amyloidosis.

[RHEUTMATIC MYALGIA COMPLICATED BY AA-AMYLOIDOSIS].

Rheumatic myalgia is associated with intense inflammation and, unlike other diseases, is very rarely complicated by AA- amyloidosis. Only 12 such cases have been described worldwide, most of them in combination with giant cell arteritis. The present article reports the first case of rheumatic myalgia complicated by AA-amyloidosis encountered in Russia and the relevant literature review.

[High-dose gamma-irradiation enhance expression of transgene under control of immediate-early CMV promoter in stably transfected tumor cells].

Gamma-irradiation is a usual method to inactivate whole-cellular anticancer vaccines consisting viable tumor cells. To evaluate the effect of gamma-irradiation to transgene expression in tumor cells we constructed several stably transfected clones of human and mouse cell lines expressing transgenic GM-CSF or GFP under control of IE-CMV promoter. Irradiation of those cells with different doses (ranged from 20 to 100 Gr) of gamma-radiation caused loss of proliferation capacity with survival of the cells population clearly depended on irradiation dose. Cell-cycle staining reveals accumulation of the cells with G2/M DNA content and almost loss of cells in S-phase. Substantial proportion of irradiated cells shows beta-galactosidase activity and morphological changes associated with cell senescence. An irradiated cell shows no changes in the level of mitochondrial dehydrogenase activity regardless irradiation dose exposed. Irradiated cells retain their ability to express transgene. Moreover, amount of the secreted GM-CSF as well as MFI in GFP-expressing cells significantly increases after gamma-irradiation up to 10 fold for cells exposed with 100 Gr. Enhancing of the transgene expression in both human and mouse cells positively correlates with total dose of gamma-irradiation gained by the cells and demonstrates gradual nature. Overall, our results supports using of 100 Gr of gamma-irradiation as the optimal dose for whole-cell anticancer vaccine inactivation.