SSCP screening of individual aptamers.

Aptamers are specific binding nucleic acids that emerge from in vitro selection. During the systematic evolution of ligands by exponential enrichment (SELEX) procedure, analysis of the sequences of the numerous selected individual molecules becomes an important step in the final stage of aptamer selection. The sequencing of cloned aptamers from the selected pool generally reveals groups of identical sequences and rarely occurring individual aptamers. This study demonstrates an approach similar to the single strand conformation polymorphism (SSCP) method used for mutation testing in genes. Human angiotensin I-specific aptamers have been used to show the efficiency of the SSCP method to classify selected individual sequences into identity groups, which minimizes sequencing efforts. Additionally this approach allows the rapid isolation and identification of aptamers from a mixture.

[The ultrastructural changes in the collagenous-elastic skeleton of the wall of the cerebral vessels in spasm in the acute period of a subarachnoid hemorrhage]. / Ul'trastrukturnye izmeneniia kollagenélasticheskogo karkasa stenki sosudov golovnogo mozga pri spazme v ostrom periode subarakhnoidal'nogo krovoizliianiia.

Electron microscopic study of arteries in spasm and ischemia of the brain revealed substantial ultrastructural changes in the vascular wall. The changes are characterized by varying thickness, edema, dissociation of fibrillar and amorphous components of internal elastic membrane of the arterial wall, by lesion in the network of collagen fibers on its inner surface, by the presence of defibrotic and uncoiled collagenous fibers of the adventitia. The changes are followed by the impairment of the arterial skeleton and hence they lead to their altered elastic properties.

Tertiary ammonium ion induces contraction of rat aorta segments and increases the mobility of lipids in the membrane of rat aorta smooth muscle cells.

The effects of tertiary ammonium ion--IEM-1194 (decyldiisopropylammonium bromide)--on smooth muscle cells (SMC) isolated from rat aorta were investigated. Using the patch-clamp technique in the cell-attached configuration, two types of effects on the Ca(2+)-activated K+ channels were recorded after application of IEM-1194: an increase in the number of fast transition bursts in open channels and the prolongation of the burst. The removal of the agonist led to the activation of these channels. Mechanical responses of aortic rings were recorded using the method of isometric tension measurements. IEM-1194 (100-400 microM) caused contractions consisting of two phases. The first phase emerged immediately after application of the agonist. The second phase was observed 10-15 min after application. The contraction of the aorta was followed by the relaxation for over 1.5 h. The same results were obtained in the Ca(2+)-free external solution. Measurements of SMC membrane fluidity by the EPR method showed that IEM-1194 induced an increase in the mobility of membrane lipids. Based on these results, we suggest a mechanism of IEM-1194 action on the Ca(2+)-activated K+ channels.

[The use of radioisotope study methods in cardiology practice]. / Primenenie radioizotopnykh metodov issledovaniia v kardiologicheskoi praktike.

Methods of radionuclide diagnosis modified with regard to the clinical problems and combined with new mathematic approaches to the processing of the data obtained make it possible to substantially enlarge the diagnostic information on myocardial contractility, central hemodynamics, the status and perfusion of the myocardium and to use it in combination with the latest research methods applied in cardiological patients.

[Findings of endoscopic examination in peptic ulcer in the area of a gastroenteroanastomosis]. / Dannye éndoskopicheskogo issledovaniia pri pepticheskoi iazve v oblasti gastroénteroanastomoza.

The work analyses results of the endoscopic examination of a pathology of gastroanastomosis in 85 patients with peptic ulcers. Most of them were postgastroresectional in origin. High diagnostic value of the method is shown which allows detection of the ulcer (in 98,8%), its exact localization and characterization of the defect, the surrounding mucosa and the nature of the ulcer.