Search PubMed⌕ Search

Biomedical subjects

I I Gitel'zon

Publications and source records attributed to I I Gitel'zon.

At least 19 recordsLinked to original sources
PubMed1990

[Perspectives of the use of bioluminescence methods in medicine].

Major advances in the development and application of the bioluminescent analysis to detect certain biologically active substances are discussed. The main merit of the method lies in its high sensitivity and specificity along with its simplicity and rapid performance. The available methodologies allow for detection of substances of varying nature: Ca2+, ATP, FMN, NAD(P), long-chain aldehydes, ATP- and NAD(P)-dependent enzymes and their substrates, many xenobiotics and antibiotics, and mutagens. The bioluminescence methodologies may be widely applied in clinical laboratory diagnosis.

Adenosine Triphosphate↗
PubMed1985

[Bioluminescent method of determining antiprotease activity].

A method for antiprotease activity measurement based on the use of luminous bacteria luciferase as protein substrate of proteases is suggested. Antiprotease is incubated with protease for 1 to 2 min at 30 degrees C and then it is added to the reaction mixture containing luciferase, NADH: FMN-oxidoreductase and their substrates--myristic aldehyde, FMN and NADH. Biofluorescence is measured in a temperature-controlled cuvette for 1 min. The total time of the measurement is 3 min. The method can be applied both in fine biochemical assays and in medical rapid diagnosis.

Humans↗
PubMed1983

[Measurement of the intensity of erythropoiesis based on the RNA content of erythrocytes].

The relationship between RNA content in erythrocytes and the erythropoiesis rate was studied at varying exposures as a result of which a simple method for erythropoietic activity testing was proposed. It consists in the measurement of ribonucleic acid content in erythrocytes of mice with a decreased erythropoiesis after administration of the test sample. Erythropoietic activity is determined from the magnitude found. The method suggested is marked by simplicity and higher sensitivity and thus may be applied in clinical medicine and research.

Animals↗
PubMed1981

[Obtaining purified erythropoietin from rabbit plasma].

A scheme of preparing partly purified erythropoietin from rabbit blood plasma is offered. The factor of purification is about 25000. Erythropoietin was purified by ion exchange chromatography on DE-32 cellulose, affinity chromatography on phytohemagglutinin-P and by gel filtration through Ultragel ACA-44. The specific activity of erythropoietin thus obtained was about 75-100 units per mg protein. The preparation may be used for exploring the regulation and differentiation of red blood cells and as an initial material for obtaining high-purified erythropoietin..

Animals↗
PubMed1977

[Effect of hypoxemia on the erythropoietic activity of organs during perfusion].

Hypoxemia (45-minute) influence in vivo on erythropoietic activity of the kidney, liver, spleen, and sternum was studied by normoxemic perfusion of the isolated organs. The erythropoietic activity proved to increase after 6-hour perfusion of the liver; this confirmed the participation of this organ in the extrarenal secretion of the erythropoietic factor.

Animals↗
PubMed1977

[Cell population mechanisms of inhibition of erythropoiesis in polycythemia].

The ciliary activity of Ctenophore bolinopsis is inhibited by decreasing concentration of Mg2+ and increasing concentration of Ca2+ in the medium. The same changes in Mg2+ and Ca2+ concentration trigger muscle contractions and bioluminescence. Co2+ arrests the cilia beating in the rectangular position. An increase in Mg2+ concentration or decrease in Ca2+ concentration switch off the nervous inhibitory mechanisms of ciliary activity, suppress muscle contractions and bioluminescence. Ni2+ produces a similar effect, but the ciliary heating is only slightly accelerated, by the contrast to the effect of increased Mg2+ concentration. A Cl-free medium Mn2+ and tetrodotoxin in commonly used concentrations are of no effect on the systems studied. Experiments involving changes in K+ concentrations and administration of tetraethylammonium suggest that the resting potential in the examined cells may be due to K+ as the most permeant ion, and that K+-channels in the cell membrane may be voltage--controlled. The proposal about "biionic" (Ca2+/Mg2+) bioelectric control of a number of intracellular reactions is discussed.

Animals↗
PubMed1975

[Dynamics of the amino acid composition of the medium during cultivation of isolated liver and kidney by the controlled perfusion method].

The dynamics of the medium amino acid composition was studied during a 6-hour perfusion of dog kidney and liver by a mixture of autogenic plasma and medium 199 (a ratio of 2 : 3). In comparison to the initial level the amount of histidine during 6-hour cultivation of the kidney was found to increase 2.2 times, that of glutamic acid--1.7 times, and of alanine and lysine--1.6 times. At the same time the amount of arginine, serine and asparagic acid became 3.3 times and of glutamine and threonine--2.5 times lower. With the liver perfusion the level of glutaminic acid became 2.9 times, of alanine--2.3 times, of cystine--2 times and of glycine--1.5 times higher. With the liver perfusion the level of arginine decreased so rapidly that none was found in the medium after a 2-hour perfusion. The described method of amino acid analysis during the cultivation of the organs could serve as means for elaborating and correcting the culture media.

Amino Acids↗
PubMed1975

[Dynamics of the amino acid composition of the medium during cultivation of isolated organs by the directed perfusion method].

The dynamics of the amino acid composition of the medium under conditions of adequate perfusion of the isolated organs of a dog (sternum, kidney and liver) was studied. It was found that after a 6-hour perfusion of the complex of organs the amount in the perfusion medium of such amino acids as histidine, lysine, alanine, considerably increased, whereas the amount of arginine, serine, aspartic acid, threonine with glutamine, isoleucine, proline, leucine and valine decreased as compared with their initial concentration. The dynamics of the amino acid medium composition during a 4-hour perfusion was studied in experiments with the isolated sternum. The concentration of alanine, lysine and histidine increased in the medium. At the same time there was seen a decrease in the concentration of serine, aspartic acid, isoleucine, tyrosine and phenyl-alanine.

Amino Acids↗