Essential hypertension (EH) is one of the most common modifiable risk factors for cardiovascular diseases and death. The aim of this study was to investigate a correlation between the levels of some cytokines (interleukins, adhesion molecules, tumor necrosis and growth factors, etc.) in the peripheral blood of patients with stage II EH and the rate of complications (myocardial infarction, acute cerebrovascular events, and transient ischemic attacks) occurring in a 5-year follow-up period. Twenty-eight cytokines were measured using ELISA, including IL1β, IL1α, IL1ra, IL18, IL18BP, IL37, IL6, sIL6r, LIF, sLIFr, IGF-1, IGFBP-1, TNFα, sTNF-RI, sVCAM-1, IL17, IL2, IL4, IL10, TGF-β1, IL8, CX3CL1, CXCL10, INFγ, M-CSF, IL34, VEGF-A, and erythropoietin, and a few vasoactive peptides, including NО, iNOS, eNOS, ADMA, SDMA, Nt-proСNP, and Nt-proBNP, in the peripheral blood samples of 200 patients with stage II EH who had been suffering from this condition for 10 to 14 years and were receiving comparable therapies to bring their blood pressure down. The patients were followed up for 5 years to keep track of complications. The retrospective analysis revealed that the group of patients who developed complications during the 5-year follow-up period exhibited a decline in the levels of IL1ra (р < 0.001) and IL10 (р < 0.001) and a rise in IL1β (р < 0.001), TNFα (р < 0.001) and M-CSF (р < 0.001) in comparison with the group of those who did not develop any complications. The multivariate Cox regression analysis was applied to the following parameters: IL1β > 18.8 pg/ml; IL1ra < 511 pg/ml; IL6 > 23.8 pg/ml; IL10 < 26.3 pg/ml; 389 pg/ml < M-CSF < 453 pg/ml; ADMA > 0.86 μmol/L; total cholesterol > 4.9 mmol/L; LDL> 3.0 mmol/L; HDL in men < 1.0 mmol/L; HDL in women < 1.2 mmol/L. The analysis revealed that M-CSF in the range from 389 to 453 pg/ml (р < 0.001) and LDL above 3.0 mmol/L (р < 0.01) correlated with an increase in the risk for end-organ damage in stage II EH. Changes in the cytokine levels can be regarded as a predictor of myocardial and cerebral damage in patients with stage II EH. Measurement of peripheral blood M-CSF can be included into the classic risk assessment schemes for the cardiovascular complications in the studied cohort of patients.

In this paper, the erythrocytes of healthy donors and people with a confirmed diagnosis of COVID-19 were tested by Raman spectroscopy and laser interference microscopy. We argue that erythrocytes (red blood cells) in COVID-19 patients have an irregular shape, and their morphometric characteristics are impaired in comparison to healthy red blood cells. Raman spectroscopy also allows us to detect a decreased oxygen transport function of these erythrocytes. The combination of these methods—Raman spectroscopy and laser interference microscopy—is a highly effective method for the diagnosis of SARS-CoV-2.

The purpose of this research is to study the characteristics of the change in the circadian rhythm of macrophage colony-stimulating factor (M-CSF) content in the peripheral blood serum of patients with stage II essential hypertension (EH) based on 5 time points (8:00, 14:00, 20:00, 2:00, and 8:00) and analyze its connection with the frequency of cardiovascular events. Materials and methods Identified levels of M-CSF in the peripheral blood serum of 60 patients with stage II EH, before and after 1 year of antihypertensive therapy using enzyme-linked immunoassays (at 8:00, 14:00, 20:00, 2:00, and 8:00). Results The research demonstrated that stage II EH patients with a medical case history lasting 10–14 years have a greater content of M-CSF in their peripheral blood serum (p > 0.001). Before the start of antihypertensive therapy, they also have an increased variability in the circadian rhythm of M-CSF content in the bloodstream (when compared with healthy individuals) due to an increase at 20:00, decrease at 2:00 and recovery at 8:00. In 70% of those patients taking antihypertensive medication and have reached their target arterial blood pressure, the cytokine decrease stabilizes at 2:00 but the increase at 20:00 remains unchanged. Thirty percent of patients retained the rhythm characteristics of M-CSF content in the blood serum typical of patients before the start of therapy. This is a predictor of an increase in the five-year risk of developing cardiovascular complications, particularly myocardial infarction and acute cerebrovascular accident, in individuals with a comparable risk of cardiovascular complications or death on the Framingham risk score.

Morphological and functional characteristics of erythrocytes, hemoglobin, and erythropoietin level in the venous blood were evaluated by laser interference microscopy, Raman spectroscopy with a short-focus extreme aperture lens monochromator, and by ELISA, respectively, in 30 patients with verified moderate COVID-19 at the time of hospitalization and 30 healthy volunteers. The patients whose course of COVID-19 has worsened to critical by day 5 had already had lower ( p <0.001) indicators at the time of hospitalization such as the area and thickness of erythrocytes, the hemoglobin distribution and packing density, hemoglobin conformation index (I 1355 /I 1550 )/(I 1375 /I 1580 ) reflecting its oxygen affinity, and blood erythropoietin content. Our findings suggest that these characteristics of erythrocytes, hemoglobin, and erythropoietin can serve as potential predictors of COVID-19 aggravation in hospitalized patients.

Pathogenetic progression mechanisms in the SARS-CoV-2–essential hypertension (EAH) system are more complex than interaction at the level of angiotensinconverting enzyme 2 (ACE2). The study was aimed to assess the dynamic changes of the IL1 members (IL1β, IL1α, IL1ra, IL18, IL18BP, IL37) blood levels in patients with EAH 10, 30, and 180 days after having COVID-19 in order to define cytokine-mediated mechanisms of EAH progression during the period following infection. The study involved four groups of patients: with a history of EAH and COVID-19 (pneumonia/no pneumonia), with a history of COVID-19 (pneumonia/no pneumonia) and no EAH. Cytokine levels were determined by enzyme immunoassay. The study results demonstrate the prolonged proinflammatory immune response during the period following infection in patients with EAH (retaining higher levels of IL1β, IL1α, and IL18 on days 10, 30, and 180 after recovery (р < 0.001) compared to levels measured prior to SARS-CoV-2 infection). In the group with no EAH, the balance of assayed cytokines was restored on day 30 of follow-up. The two-fold increase of blood IL18 levels in patients, having a history of EAH and COVID-19 and showing no increase in the IL18ВР levels after 30 days of follow up compared to the values measured prior to infection, is associated with cardiovascular complications occurring during the first six months of follow-up. This makes it possible to hypothesize the importance of these immunoregulatory peptides for the pathogenesis of complications and enhances the relevance of further scientific research.