Biomedical subjects

V V Zenin

Publications and source records attributed to V V Zenin.

23 records · Page 2Linked to original sources

PubMed1982

[Dependence of 3T6 cell proliferation on the serum concentration in the medium].

The characteristics of 3T6 cells in various growth phases and their reaction to the serum content decrease was studied using flow cytofluorimetry, autoradiography and thymidine incorporation in acid-insoluble cell fraction. It is concluded that 3T6 cells are arrested in G1 period after reaching the confluent state, or when the serum concentration in the cultural medium is below 0.5%. The "quiescence" state of 3T6 cells cannot be identified with Go state. The variable data seen in the case of the culture transfer into the medium with decreased serum content may suggest the necessity to control the arrest of cell proliferation in each case examined.

Animals↗

PubMed1978

[Determination of the permeability coefficients of spherical bilayer membranes for ions and nonelectrolytes].

A method for determining permeability of spherical lipid bilayer membranes for ions and nonelectrolytes is proposed. This method is based on measuring the quantity of substances penetrating inside some membrane limited volume. This method allows to measure the permeability coefficient of several substances in one membrane. Permeability coefficients have been measured in non-modified membranes for glucose. Li, K, and in membranes modified with amphotericin B for glucose, ribose and lactate.

Amphotericin B↗

PubMedDate not supplied

[A device for sample pretreatment during flow cytometry].

A device for the preliminary treatment of samples immediately prior to flow cytofluorimetric analysis is described. The device is intended for several procedures: (a) mixing of batched sample volumes with the reagent and efficient stirring of the mixture; (b) disintegration of cell aggregates; and (c) disruption of cell membranes to release the cell contents (chromosomes, micronuclei, nuclei etc.). The pretreatment is useful for studying the kinetic parameters of fast cellular processes in the flow, a more correct analysis of the cell cycle and the study of karyotypes of single mitotic cells. The device was called a magnetic microstirrer.

Cell Aggregation↗

PubMedDate not supplied

[A novel method of chromosome distribution analysis in saccharose density gradient].

The human chromosomes distribution in a sucrose density gradient was studied using a new computer method of the quantitative analysis of flow karyotypes. The dual-parameter flow distributions of human chromosomes fluorescence intensities of the sucrose density gradient fractions were analyzed to obtain the quantity of each chromosome. The chromosomes were found to distribute over sucrose density gradient as follows: 1) fractions with low sucrose density mostly contain chromosomes 1-7, and their quantity is increased between 1.4- to 3.2-fold in comparison with the control unfractionated suspension; 2) medium density fractions are enriched with chromosomes 8-20 up to 2.4-fold; 3) fractions with a high sucrose density mostly contain small chromosomes 21-22 and fragments of broken chromosomes. So the new method of quantitative analysis of flow karyotypes allows one to determine the efficiency of enrichment and the maximally enriched fraction for any chosen chromosome. Maximally enriched fractions maximize the rate of preparative flow sorting of individual chromosomes for research or biotechnology purposes.

Cell Line↗

PubMedDate not supplied

[Method to increase efficiency of irradiation of biological objects by electron beams].

The method has been proposed for active control of distribution of the dose caused by an electron beam passed through the medium. The method is based on the influence of magnetic field on charged particles and it allows concentrating of the absorbed dose in the prescribed area. To investigate this method the Monte-Carlo simulations were carried out for 20-70 MeV electrons in 0.5-3 T magnetic field using GEANT program. From the obtained results it follows that in the uniform magnetic field the maximum in distribution of the electron beam dose appears and its shape is similar to Bregg's peak for heavy charged particles. The location of the maximum may be changed by varying beam energy and magnetic fields configuration. For 60-70 MeV beam the maximum may be obtained at the depth of 10-15 cm that is convenient for radiotherapeutic usage.

Electromagnetic Fields↗