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PubMedDate not supplied

[The use of immobilized enzymes for the synthesis of nucleosides and nucleotides including the ones labeled with radioactive isotopes].

Nucleoside phosphorylases from E. coli immobilized in polyacrylamide gel were used for production of nucleosides from nitrous bases during the transglucosylase reaction. Phosphorylation of nucleosides resulted in the formation of 5'-nucleotides was performed in the presence of carrot nucleoside phosphotransferase immobilized in polyacrylamide gel. Using 14C-labelled nitrous bases as starting substrates, labelled nucleosides and nucleotides can be obtained with the 75-80% yield that have radioactive purity of 95-99%. The stability of the immobilized enzymes was being studied under the conditions of the reactions using them in the batch and plug flow reactors.

Enzyme Stability↗
PubMed1994

LB-145 a new radioactive isotope eliminating product with high selectivity.

LB-145 is a macrocyclic ligand, which forms, 200 times more stable complex with Stroncium (Sr) ions, than with calcium ones. The product is not toxic, it has no effect on circulation, respiratory system. 85,90Sr and 144Ce were given oral, i.p., s.c. or by inhalation, LB-145 either prophylactic or 30 (60) minutes after the radiointoxication i.v. or i.p. to the animals. The isotope contents of the organism were measured by whole body autoradiography, liquid scintillation, or by NK 350 ratemeter. One injection given prophylactic inhibited the incorporation of isotopes into the organism, within 24 hours after radiointoxication 75-80% of the isotopes were excreted by urine and faeces on the first day, 90-95% excreted on the first week. Also the isotope contents of femur and scissors were mobilised. The suggested human dose-0.5 g/70 kg bw-can be life-saving antihavaric injection.

Animals↗
PubMed1986

Analysis of protein incorporation of radioactive isotopes in the Chinese hamster ovary cell cycle by electronic sorting and gel microelectrophoresis.

The patterns of [3H]-leucine and [32P]-phosphate incorporation of proteins extracted with varying molarities of sodium chloride were analyzed from nuclei physically sorted from six fluorescence windows after propidium iodine staining of the G0 + G1 and G2 + M phases of the Chinese hamster ovary (CHO) cell cycle. Eight hundred nanograms of protein were used in each electrophoretic analysis obtained from 200,000 nuclei, a portion of the sample, from each window. Autoradiography was performed in a two-dimensional polyacrylamide gel ultra-microelectrophoresis apparatus (UMEA) designed and fabricated in this laboratory. There was a net reduction and/or loss of [3H]-leucine- and [32P]-phosphate-labeled protein regions from the autoradiographs occurring primarily in the G2 + M phase. Two phosphorylated proteins that were stage specific were observed in partitions of the G2 + M phase. The use of isolated proteins and the coelectrophoresis of these markers demonstrated the similarity in mobility of a number of proteins seen in the autoradiographs of proteins extracted with high and low salt molarities and implied they are synonymous. Coelectrophoresis indicated that a substantial number of high molecular weight proteins that decreased or disappeared at late stages of G2 + M and early mitosis were composed, in part, of nucleolar proteins.

Animals↗