Experimental and Computational Study of Hyaluronidase Interactions with Glycosaminoglycans and their Ligands.

Covalent conjugation of hyaluronidase with copolymeric glycosaminoglycans (GAG, heparin and dermatan sulfate) considerably inactivates the enzyme, while conjugation with polymeric GAG (chondroitin sulfate and hyaluronan) improves its stability. These effects are associated with structural differences of these GAG caused by С-5 epimerization of glucuronic and iduronic acid residues and different effects of (α[1 - 4] and α[1 - 3] relative to β[1 - 4] and β[1 - 3]) glycosidic bonds. Pronounced effects of galactose C-4 epimers (in comparison with glucose) and disaccharide mixture (lactose, cellobiose, maltose) on endoglycosidase activity of hyaluronidase emphasize the importance of its diversified multi-contact microenvironment.

Cancer/testis genes expression in human melanoma cell lines.

We analyzed the expression of 15 cancer/testis and four melanoma differentiation antigens in 21 metastatic melanoma cell lines using reverse transcriptase-polymerase chain reaction (RT-PCR) assay. On the basis of morphological characteristics, tumor cell lines were divided into three groups with high, moderate, and low grade of differentiation. Evaluation of gene expression and melanoma cell morphology has revealed a correlation between increased expression of cancer/testis genes and differentiation grade of cancer cells.

Atrial appendage transcriptional profile in patients with atrial fibrillation with structural heart diseases.

During the last few years DNA microarray studies of gene expression changes in human atrial tissues from patients with and without atrial fibrillation (AF) have been performed. For this purpose, tissue samples are usually collected from AF patients undergoing open heart surgery. These investigations have limitations associated with the unavoidable heterogeneity of compared groups which is due to the presence of various structural changes accompanying different sets of underlying heart diseases in both groups.

In vitro selection of single-stranded DNA aptamers that bind human pro-urokinase.

Single-chain pro-urokinase is an inactive proenzyme form of human urokinase (urinary plasminogen activator) with a Mr of 50,000 which is converted to the active two-chain form by catalytic amounts of plasmin. It is used for thrombolytic therapy of acute myocardial infarction and acute ischemic stroke. We have isolated single-stranded DNA molecules with significantly increased binding affinity for human pro-urokinase by SELEX (systematic evolution of ligands by exponential enrichment) procedure from a pool of 10(15) molecules containing 24 randomized positions which are flanked by defined regions.

Total RNA suitable for molecular biology analysis.

Development of methods based on determining expression of individual genes resulted in the need for large amounts of high quality RNA preparations. It is widely accepted that in intact rRNA the 28S and 18S band ratio must be 2:1. It is not quite clear what is the main cause of lower rRNA bands intensity ratio.

Carbocyclic dinucleoside polyphosphonates: interaction with HIV reverse transcriptase and antiviral activity.

Carbocyclic alpha, gamma-bis(nucleoside)-5,5'-triphosphonates and alpha, delta-bis(nucleoside)-5,5'-tetraphosphonates (Ap4A and Gp4G) analogues were shown to be a new type of terminating substrate of HIV reverse transcriptase. They effectively inhibited the DNA synthesis catalyzed by this enzyme in model cell-free systems, but their antiviral activity both in Rat1 fibroblast cell culture bearing MLV reverse transcriptase and in HIV-infected MT-4 cells was low. When a liposome delivery system was used, the antiviral efficacy of the compounds under study was increased.