Blood Circulation Pattern in Highly Skilled Swimmers

Echocardiography was used to study the parameters of cardiodynamics, systemic hemodynamics, left ventricular morphology and functioning, phase analysis of cardiac activity, and rheological blood properties in highly skilled expert swimmers. The relationship between different levels of blood circulation was established. A close correlation between the blood flow at rest and arterial pressure was found to contribute to the optimization of microvascular pressure and shear stress in accordance with body demands.     

Interplay between recombinant Hsp70 and proteasomes: proteasome activity modulation and ubiquitin-independent cleavage of Hsp70

The heat shock protein 70 (Hsp70, human HSPA1A) plays indispensable roles in cellular stress responses and protein quality control (PQC). In the framework of PQC, it cooperates with the ubiquitin-proteasome system (UPS) to clear damaged and dysfunctional proteins in the cell. Moreover, Hsp70 itself is rapidly degraded following the recovery from stress. It was demonstrated that its fast turnover is mediated via ubiquitination and subsequent degradation by the 26S proteasome. At the same time, the effect of Hsp70 on the functional state of proteasomes has been insufficiently investigated. Here, we characterized the direct effect of recombinant Hsp70 on the activity of 20S and 26S proteasomes and studied Hsp70 degradation by the 20S proteasome in vitro. We have shown that the activity of purified 20S proteasomes is decreased following incubation with recombinant human Hsp70. On the other hand, high concentrations of Hsp70 activated 26S proteasomes. Finally, we obtained evidence that in addition to previously reported ubiquitin-dependent degradation, Hsp70 could be cleaved independent of ubiquitination by the 20S proteasome. The results obtained reveal novel aspects of the interplay between Hsp70 and proteasomes.     

ACE and AGTR1 Polymorphisms in Pathogenesis of Human Left Ventricular Hypertrophy

The A2350G polymorphism of exon 17 of the angiotensin I-converting enzyme gene (ACE) and the A1166C polymorphism of the 3-untranslated region (3-UTR) of the angiotensin II type 1 receptor gene (AGTR1) were tested for association with left ventricular hypertrophy (LVH) in patients with essential hypertension (EH) or arterial hypertension (AH) combined with diabetes mellitus type 2 (DM2). The patients with EH or AH + DM2 did not differ significantly in ACE or AGTR1 allele or genotype frequencies from healthy subjects. Both polymorphisms were associated with LVH in EH. AGTR1 allele 1166C was more frequent in patients with LVH than without (33.6 vs. 20.7%) and affected the left ventricular mass index (LVMI) in patients with EH (p = 0.007). The frequency of ACE allele 2350G in EH patients with LVH was 1.5 times higher, and that of genotype GG was 3.5 times higher, than in patients without LVH. LVMI differed significantly (p = 0.002) between patients with different ACE genotypes, being maximum in homozygotes GG and minimum in homozygotes AA. Thus, AGTR1 allele 1166C and ACE allele 2350G were identified as predisposing to LVH in EH. The two polymorphisms were not associated with the incidence or severity of LVH in patients with AH and DM2.     

Structure and function of enteric alpha defensins in norm and pathology

This review summarizes currently available data on enteric alpha defensins structure, their functions in the innate and adaptive immunity systems and the role in development of intestinal illnesses.     

Identification of proteins with altered expression in colorectal cancer by means of 2D-proteomics

Modern proteomic techniques make it possible to identify numerous changes in protein expression in tumors as compared to normal tissues. Although proteomics is currently widely used, identification of proteins differentially expressed in particular types of cancer remains a challenging task. The goal of our study was to detect novel protein markers of colorectal cancer using comparative proteomics of protein extracts obtained from primary tumors and adjacent normal tissues. Coloreetal cancer is nearly asymptomatic at the early stages, which calls for development of fast and sensitive methods for molecular diagnostics. Proteomes of 11 paired specimens of primary colorectal tumors and adjacent histologically normal tissues were studied using comparative 2D PAGE. Altogether, 16 proteins with altered expression levels were detected, including 13 proteins with increased levels and three proteins with decreased levels in tumor tissues. These proteins were identified using MALDI-TOF mass spectrometry. The proteins GPD1, RRBP1 (increased levels), HNRNPH1, and SERPINB6 (decreased levels) have been associated with colorectal cancer for the first time.     

Holliday junction formation by the Borrelia burgdorferi telomere resolvase, ResT: implications for the origin of genome linearity

Spirochetes of the genus Borrelia include the causative agents of Lyme disease and relapsing fever. They possess unusual, highly segmented genomes composed mostly of linear replicons with covalently closed hairpin telomeres. The telomeres are formed from inverted repeat replicated telomere junctions ( rTel s) by the telomere resolvase, ResT. ResT uses a reaction mechanism with similarities to that employed by the type IB topoisomerases and tyrosine recombinases. Here, we report that the relationship of ResT to the tyrosine recombinases extends to the ability to synapse-replicated telomeres and to catalyse the formation of a Holliday junction. We also report that ResT can use asymmetrized substrates that mimic the properties of a recombination site for a tyrosine recombinase, to form Holliday junctions. We propose a model for how this explains the origin of genome linearity in the genus Borrelia.     

Long-term results of chronic occlusion recanalization in patients with coronary heart disease

The study was undertaken to assess the long-term results of recanalization of chronically occluded coronary arteries, by applying drug-eluting stents to patients with coronary heart disease. The study enrolled 585 patients with one-vessel occlusive lesion of one of three great coronary arteries (TIMI 0; occlusion duration, > or = 3 months): 321 patients who underwent successful recanalization of chronic occlusion and further implantation of drug-eluting stents and 264 patients who received drug therapy (a control group). The short- and long-term results of recanalization were investigated. The follow-up averaged 1095 +/- 36 days; reexaminations were made after 1, 2, and 3 years. The direct success rate of recanalization of chronically occluded coronary arteries was 84.9% (321/378). The results of a 3-year follow-up showed the efficiency and expediency of endovascular recanalization of chronic occlusions: the invasively treated patients had the symptoms of angina pectoris and heart failure significantly less frequently, showed higher exercise tolerance and a less need for antianginal therapy, and had a better long-term prognosis.