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We studied the relationship of inotropic responses of the isolated myocardium to stimulation of β 1 -and β 2 -adrenergic receptors (β-AR) with echocardiography parameters in 28 patients with coronary heart disease (CHD). Myocardial fragments (trabeculae of the right atrial appendage) were obtained during coronary artery bypass surgery. The inotropic response of the trabeculae was assessed in an isometric mode. Stimulation of β 1 -and β 2 -AR with agonists was performed against the background of preliminary α-AR blockade. In case of preserved ejection fraction, significant inotropic response of the trabeculae (135 (112; 154)% from the initial contraction amplitude) was observed after β 1 -AR stimulation, while in reduced ejection fraction, its significant increase was observed after β 1 -AR stimulation (126 (112; 170)% from the initial contraction amplitude). In patients with preserved and reduced ejection fraction, the correlations between the inotropic responses of the trabeculae to β 1 -and β 2 -AR stimulation and echocardiography parameters were different. The revealed differences reflect the degree of cardiac remodeling under condition of the studied pathology., (© 2024. Springer Science+Business Media, LLC, part of Springer Nature.)

We compared the expression of Са 2+ -ATPase (SERCA2a), calsequestrin (CASQ2), ryanodine receptors (RyR2) proteins and their genes (ATP2A2, CASQ2, and RYR2) in coronary heart disease (CHD) patients with and without comorbid type 2 diabetes mellitus. All studies were performed on the right atrial appendages resected during coronary bypass surgeries. Expression of SERCA2a and RyR2 proteins and their ATP2A2 (p=0.046) and RYR2 genes in comorbid pathology was significantly (p=0.042) higher (by 1.2 and 2 times; p=0.025). The expression of CASQ2 protein and its gene did not differ significantly between the groups (p=0.82 and p=0.066, respectively). It was concluded that the expression of SERCA2a and RyR2 proteins and their genes (but not CASQ2 and its gene) is elevated in CHD associated with type 2 diabetes mellitus. Expression of the studied proteins correlated with the expression of their genes. Increased expression of CASQ2 protein and its gene can probably prevent imbalance of the Ca 2+ -transporting systems in cardiomyocytes and contractile dysfunction of the myocardium, even in CHD associated with type 2 diabetes mellitus., (© 2021. Springer Science+Business Media, LLC, part of Springer Nature.)

We compared the capability of human fibroblasts to populate porous polycaprolactone (PCL) scaffolds modified during fabrication with surface-active agents Triton Х-100 (type 1 scaffold) and polyvinylpyrrolidone (type 2 scaffold). The mean fiber diameter in both scaffolds was almost the same: 3.90±2.19 and 2.46±2.15 μ, respectively. Type 1 scaffold had higher surface density and hydrophilicity, when type 2 scaffold was 1.6 times thicker. The cells were seeded on the scaffolds by the dynamic seeding technique and then cultured in Petri dishes with nutrient medium in a humid atmosphere. During 3-day culturing, no cell release from the matrix was noted. DAPI staining proved the presence of cells in both scaffolds. However, in type 1 scaffold the cells populated the whole thickness, while in type 2 scaffold, the cells were present only in the superficial layer. These findings suggest that PCL scaffolds modified with Triton Х-100 or polyvinylpyrrolidone are not cytotoxic, but the structure of the scaffold treated with Triton Х-100 is more favorable for population with cells.