Peculiarities of Cell Seeding on Electroformed Polycaprolactone Scaffolds Modified with Surface-Active Agents Triton X-100 and Polyvinylpyrrolidone.

We compared the capability of human fibroblasts to populate porous polycaprolactone (PCL) scaffolds modified during fabrication with surface-active agents Triton Ð¥-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 Ð¥-100 or polyvinylpyrrolidone are not cytotoxic, but the structure of the scaffold treated with Triton Ð¥-100 is more favorable for population with cells.

[Inflammation as a universal pathogenetic link between injury, repair and regeneration, in acute coronary syndrome. From experiment to clinic].

Theory of atherogenesis and its complications underwent numerous changes. Today we observe that inflammation is a universal pathogenetic link between various processes such as atherosclerosis, rupture of atherosclerotic plaques and following myocardial infarction, post-infarction cardiac repair and heart failure. This review discusses examples, difficulties, and prospects of implementation of anti-inflammatory therapies in management of acute coronary syndrome and its complications.

[Detection of Antigens of Cardiotropic Viruses in Atherosclerotic Plaques in Patients with Fatal Myocardial Infarction].

AIM: To assess the frequency of detection of cardiotropic virus antigens in coronary artery atherosclerotic plaques in patients with fatal myocardial infarction (MI). MATERIALS AND METHODS: We examined fragments of coronary plaques of 12 patients with fatal type 1 MI. Immunohistochemistry (IHC) of plaques was performed with the paraffin blocks using antibodies to Herpes simplex virus (HSV)-1, HSV-2, HSV-6, cytomegalovirus (CMV), parvovirus B19, adenovirus, Epstein-Barr virus and enteroviruses. RESULTS: According to the IHC all patients had virus antigens. The most common virus agents in fragments of coronary plaques were HSV-6 (10 patients) and enteroviruses (5 patients). Antigens of CMV, parvovirus B19, adenovirus, Epstein-Barr virus were not detected in any case. CONCLUSIONS: In this study viral antigens in coronary artery atherosclerotic plaques were found in all victims of fatal MI. There was no difference in the frequency of detection and type of viral agents between plaques in culprit arteries and uncomplicated atherosclerotic plaques.

[Dynamics of brain CD68+ and stabilin-1+ macrophage infiltration in patients with myocardial infarction].

Te aim of the study was to evaluate the temporal dynamics of brain CD68+ and stabilin-1+ macrophage infltration in patients with fatal myocardial infarction (MI) type 1. MATERIALS AND METHODS: Te study included 31 patients with fatal MI type I. Te control group comprised 10 patients of 18-40 age group who died from injuries incompatible with life. Patients with MI were divided into two groups. Group 1 comprised patients who died during the frst 72 hours of MI, group 2 comprised patients who died on days 4‒28. Macrophage infltration in the brain was assessed by immunohistochemical analysis. We used CD68 as a marker for the cells of the macrophage lineage and stabilin-1 as an M2-like macrophage biomarker. RESULTS: In group 1 the number of brain CD68+ macrophages was signifcantly higher than in the control group. In group 2 the intensity of brain CD68+ cells infltration was lower than in group 1 and higher than in the control group. Tere was a small amount of stabilin-1+ macrophages in the brain of healthy people, as well as of patients who died from MI. Tere were no signifcant differences in the number of stabilin-1+ cells between group 1 and group 2. Correlation analysis revealed the presence of positive correlation between the number of CD68 + macrophages in the infarct, peri-infarct, and non-infarct areas of the myocardium and the number of CD68+ macrophages in the brain in patients with MI. Tere were not correlations between the number of CD68 + and stabilin-1+ cells and the presence of diabetes mellitus, history of stroke, history of MI, and pre-infarction angina. CONCLUSION: Te number of brain CD68+ macrophages signifcantly increased during the frst three days of MI. Te number of brain stabilin-1+ macrophages did not increase and did not differ from the control values. We observed a positive correlation between the number of CD68+ macrophages in the brain and myocardium.

Peculiarities of Cell Seeding on Polylactic Acid-Based Scaffolds Fabricated Using Electrospinning and Solution Blow Spinning Technologies.

We studied the possibility of seeding bone marrow-derived stromal cells onto polylactic acid-based scaffolds fabricated by electrospinning and solution blow spinning technologies. The cells were applied to the scaffolds by dynamic seeding and scaffolds were then cultured in Petri dishes in culture medium for 3 days. Cell migration to the Petri dish surface was noted only for scaffolds fabricated by electrospinning technology, but DAPI staining confirmed the presence of cells in both scaffolds. The mean number of cells in scaffolds fabricated by electrospinning and solution blow spinning was 56±9 and 81±6, respectively. The scaffold fabricated by solution blow spinning was more effectively (p<0.05) colonized by cells due to its more optimal spatial structure.

Myocardial Protection against Ischemic and Reperfusion Injuries (Experimental Study).

The effects of hypoxic, hyperoxic, and hypoxic-hyperoxic preconditioning were examined in the prospective study on narcotized and artificially ventilated rabbits. Under artificial circulation, acute myocardial ischemia was modeled by ligation of anterior descending coronary artery, which was followed by reperfusion. The degree of ventricular arrhythmias was assessed, and the ischemic area was evaluated in percent of the area at risk. Microscopic characterization of the myocardium was employed to assess the cardioprotective effect of hypoxic and/or hyperoxic preconditioning. According to Kruskal-Wallis test, the greatest resistance of the myocardium to ischemic and reperfusion injury was observed after hypoxic-hyperoxic preconditioning (H=42.459; p=0.009). The rabbits subjected to this type of preconditioning demonstrated the least damaged myocardium in comparison with nonconditioned controls.

[Determination of the efficiency of single-photon emission computed tomography with 99mTc-HMPAO-labelled leukocytes in the diagnosis of myocarditis: Comparison of scintigraphic and histological data].

OBJECTIVE: to determine the efficiency of single-photon emission computed tomography (SPECT) with 99mTc-HMPAO- labelled leukocytes in diagnosing myocarditis, by comparing scintigraphic and histological data. MATERIAL AND METHODS: The investigation enrolled 35 patients with suspected myocarditis, who were planned to undergo coronaroventriculography or intervention with endomyocardial biopsy. Prior to endomyocardial biopsy, all the patients underwent myocardial scintigraphy using 99mTC-exametazime-labelled leukocytes. The results of myocardial scintigraphic and histological examinations were compared. RESULTS: Abnormal myocardial 99mTc-HMPAO-labelled leukocyte accumulation was detected in 7 (20%) examinees. Myocarditis was histologically verified in 9 (25.7%) persons. Our findings showed that the sensitivity of 99mTc-HMPAO-labelled leukocyte SPECT in diagnosing myocardial inflammatory changes was 62%; its specificity and diagnostic accuracy were 92% and 85%, respectively. Conclusion. 99mTc- HMPAO-labelled leukocyte scintigraphy is today one of a few procedures for the primary noninvasive diagnosis of myocardial inflammation. However, in view of its sufficiently low sensitivity and laboriousness and the sigh cost of consumables, the technique is irrationally used in routine clinical practice.

Radiofrequency ablation as a possible method for preparing pathologically altered myocardium for intramyocardial cell transplantation.

We studied the effects of radiofrequency ablation on the results of intramyocardial transplantation of bone marrow NSC into the myocardium of rats with postinfarction cardiosclerosis. It was shown that exposure of the pathologically changed myocardium to radiofrequency radiation led to destruction of formed connective tissue. Transplantation of MSC into sites exposed to radiofrequency radiation promoted the development of regenerative processes (abundant infiltration with mononuclear cells, presence of granulation tissue, and numerous newly formed blood vessels). We concluded that preliminary radiofrequency irradiation of the myocardial areas promotes realization of the regenerative potential of cell transplantation.

Economical technology of creation of cell-free matrix of animal and human arterial vessels.

We present a technology of creation of blood vessel connective tissue framework by 2-3-h vessel perfusion with detergents. The technology ensures effective removal of vascular cells without damaging collagen and elastic fibers. The connective tissue frameworks prepared by this method can the used for restoring blood flow in various vascular pathologies. The presented approach attenuates the damaging effect of treatment on the vascular framework due to maximum simplification and shortening of the duration of treatment and is universal for human and animal vessels.

Evaluation of the efficacy of granulocyte colony-stimulating factor for the treatment of experimental myocardial destruction in mice.

We studied the effects of recombinant granulocytic CSF on heart remodeling in BALB/c mice after cryodestruction. Administration of granulocytic CSF was started 1 day after cryodestruction (subcutaneously, 10 µg/kg/day, for 4 days). As early as after the first injection, leukocytosis in the peripheral blood started to develop, leukocyte count peaked on days 4-6 and returned to normal on day 14. Treatment with granulocytic CSF significantly increased the content of progenitor cells in the bone marrow and led to rapid development of the inflammatory reaction and myocardium infiltration with mononuclear cells. Injections of granulocytic CSF did not reduce scar area, but provided significantly less pronounced heart hypertrophy, which attests to its better functional properties. By day 30 after cryodestruction, control animals and animals receiving granulocytic CSF exhibited similar morphological picture at the site of damage. Thus, our regimen of granulocytic CSF administration produced a mobilizing effect on bone marrow progenitor cells and postinfarction heart remodeling. Direct effects of granulocytic CSF on the heart have to be established for its use in the treatment of myocardial infarction.