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V V Novikov

Publications and source records attributed to V V Novikov.

At least 19 recordsLinked to original sources
PubMed1998

Combined action of static and alternating magnetic fields on ionic current in aqueous glutamic acid solution.

Combined parallel static and alternating magnetic fields cause a rapid change in the ionic current flowing through an aqueous glutamic acid solution when the alternating field frequency is equal to the cyclotron frequency. The current peak is 20-30% of the background direct current. The peak is observed with slow sweep in the alternating magnetic field frequency from 1 Hz-10 Hz. Only one resonance peak in the current is observed in this frequency range. The frequency corresponding to the peak is directly proportional to the static magnetic field. The above effect only arises at very small alternating field amplitude in the range from 0.02 microT-0.08 microT.

Cyclotrons↗
PubMed1994

A study on the mechanism of polymerisation of Bacillus brevis flagellin.

Optical properties of intact flagellin and of modified-on-tyrosine flagellin incapable of self-assembly have been studied by the circular dichroism (CD) method. The CD spectra of both flagellins do not change and virtually coincide within the pH range from 2.9 to 10.0. In the presence of polyethylene glycol (PEG) and ammonium sulfate which accelerate flagellin polymerization, the character of the CD spectra changes and depends on pH. The increase in the PEG content to 20% and that in the ammonium sulfate content to 1 M over the pH range from 4.3 to 10.0 results in a significant rise of the molar ellipticity at 222 nm ([theta]222) of both flagellins. However, [theta]222 does not reach values typical for bacterial flagella. The results obtained are discussed with respect to conformational changes in the flagellin molecule during polymerization.

Bacillus↗
PubMed1993

[ICO-166 monoclonal antibodies against the CD45RA antigen].

Monoclonal antibodies (MCA) ICO-166 against CD45RA antigen were generated and characterized. In the indirect IFA, MCA ICO-166 reacted with 54.1 +/- 1.9% lymphocytes of human peripheral blood and 15.2 +/- 2.3% monocytes but not with granulocytes or thrombocytes. The method of double labelling of cells demonstrated that MCA ICO-166 detected all B-lymphocytes, all NK-cells and 31% of mature T-lymphocytes but only 55% of CD8 suppressor cells and only 21% of CDA helper cells carried this antigen on the surface. Experiments were carried out to block binding of FITC-labeled MCA ALB11 against CD45RA antigen with human lymphocytes by pretreatment of cells with different concentrations of MCA ICO-166. Treatment of cells with MCA ALB11 blocked binding of MCA ALB11-FITC by 85% on the average. MCA ICO-166 blocked binding of MCA ALB11-FITC by 66% on the average. When different dilutions of MCA ICO-166 were used, the dose-dependent effect of blocking of MCA ALB11-FITC binding was observed. MCA ICO-166 immunoprecipitated a protein band of molecular weight 220 kDa from lysates of mononuclear cells of the human peripheral blood.

Animals↗
PubMed1989

[Karyological analysis of hybridoma cells after prolonged cultivation].

The karyological properties, the level of monoclonal antibody production and the proliferative properties of hybridoma strains after their prolonged passage in vivo and in vitro have been studied. Hybridoma EKO-G-2 having the supertetraploid set of chromosomes has proved to be a more stable antibody producer and to possess better proliferative properties. The suggestion has been made that the stability of antibody production is linked with the surplus number of chromosomal copies.

Animals↗
PubMed1989

[The possibility of using outbred mice for the production of monoclonal antibodies].

Outbred laboratory mice, pretreated with an ascites-forming stimulator and an irradiation dose of 6 Gy, can be used for the production of monoclonal antibodies. However, the passage of hybridomas in irradiated outbred mice rapidly leads to the death of the cells. The properties of antibodies obtained from ascitic fluid of outbred mice are no different from those of antibodies obtained from BALB/c mice.

Animals↗
PubMed1988

[Comparison of the action of pristan and Freund's incomplete adjuvant on the development of ascites in mice--the recipients of hybridoma cells].

Production of immunodiagnostic preparations based on monoclonal antibodies requires large amounts of such antibodies. Most frequently preparative quantities of monoclonal antibodies are provided by ascitic fluid from hybridoma-carrying mice. Prior to intraperitoneal administration of hybridoma cells mice are subjected to stimulation with pristan, a mineral oil component. The authors showed that the Freund's incomplete adjuvant (FIA) may be as well used for this purpose. The effect of pristan and the FIA on ascites development in mice with hybridomas producing monoclonal antibodies to the Ia-like antigens of man was studied. The stimulants were administered in amounts of 0.5 ml per a mouse. It was shown that irrespective of the stimulant injection time and the number of the administered hybridoma cells the amount of the ascitic fluid formed in female mice BALB/c stimulated with the FIA was 1.5-3 times higher as that in the animals stimulated with Pristane, the antibody titer in the ascitic fluid being unchanged.

Animals↗
PubMed1988

[Passage of hybridomas in male BALB/c mice].

For cultivating hybridomas in the ascitic form there are usually used female mice BALB/c and not male ones. Efficiency of production of monoclonal antibodies with cultivation of the hybridomas in male and female mice BALB/c was studied comparatively. The animals were stimulated to form ascite by administration of the incomplete Freund's adjuvant or 3 per cent peptone with petrolatum oil. Some parameters of the ascite formation were studied: viability of the hybridoma cells, ascitic fluid formation period and volume, hybridoma cell concentration and titers of monoclonal antibodies in the ascitic fluid. In regard to all the parameters studied the male animals were not inferior to the female ones and in case of one of the hybridomas even surpassed them twofold by the volume of the ascitic fluid formed. This is evident of possible using male mice for mass cultivation of hybridoma cells with a purpose of obtaining preparative amounts of monoclonal antibodies in production of immunodiagnostic agents on their basis.

Animals↗
PubMed1988

[Vaseline-peptone mixture as a stimulant of ascites formation in mouse hybridoma carriers].

A preliminary injection of vaseline oil with 3% of peptone in a dose of 0.5 ml induced ascitic tumors with a high taking rate in mice used as recipients of hybridomas. The dependence of the amount of ascitic fluid produced in such animals and the content of monoclonal antibodies on the time of the preliminary injection of the above-mentioned mixture, the number of cells introduced into the recipient animal, and the time of ascites collection has been studied. The optimal scheme of obtaining ascites with the use of the proposed mixture is presented. The comparison of the mixture with other stimulants of ascites production has been made.

Animals↗
PubMed1984

[ICO-1 monoclonal antibodies against the constant region of Ia-like (Dr) antigens].

Mouse monoclonal antibodies ICO-1 to constant part of Ia-Like (Dr) antigens were produced. Hybridoma continuously produced IgG3 antibodies during 22 passages in vivo, more than 7 months in vitro. Antibodies specifically bound to 29.1 +/- 2.3% of peripheral blood mononuclear cells of healthy people recognized the antigen on B lymphocytes and 44.2 +/- 3.4% of monocytes. This antigen was absent on granulocytes and T lymphocytes. Using monoclonal antibodies ICO-1 antigenically positive cells were detected in 40 patients with B-CLL, in 12 of 35 patients (34.3%) with chronic granulocytic leukemia at the stage of blastic crisis, in 43 of 65 patients (66.1%) with ALL, in 14 of 38 patients (36.8%) with lymphosarcoma and in 17 of 30 patients with acute myelomonocytic leukemia. The antibodies responded to surface antigens in the reaction of indirect surface immunofluorescence, complement-dependent cytotoxic reaction and radioimmune tests.

Animals↗
PubMed1983

[Mechanism of flagellin polymerization in Bacillus brevis].

The optical properties of acid-dissociated and tetranitromethane-modified flagellin has been studied by circular dichroism (CD) techniques. The flagellins have the same CD spectra which do not change over the 2.9-10.0 range. The spectra character depends on pH in the presence of polyethylene glycol (PEG) and ammonium sulphate which accelerate polymerization. As the content of PEG goes up to 20% and ammonium sulphate to 1 M, the value of the molecular ellipticity at 222 nm ([O]222) of the both flagellins considerably increases at pH 4.3-10.0, however [O]222 does not achieve the value for bacterial flagella. PEG and ammonium sulphate addition at pH 2.9-3.9 gives less dramatic increase of the [O]222 value. It has been concluded that the changes in the CD spectra at pH 4.3-10.0 is a result of conformational rearrangements in flagellin before it incorporates into the flagella.

Bacillus↗
PubMed1981

[Polymerization of bacterial flagellar flagellin in the presence of polyethyleneglycol].

Polymerization of flagellin from the flagella of Bacillus brevis in the presence of polyethyleneglycol (PEG) with molecular weight varying from 400 to 40 000 was studied. When 10% PEG2000-6000 was used, polymerization was completed within 5 min. When PEG with higher molecular weights were used, their higher concentrations were necessary. Polymerization of flagellin in the presence of PEG400-600 did not practically differ from that without PEG. At flagellin concentrations up to 0.1 mg/ml the polymerization process with PEG also occurred at a very high rate. Polymerization of flagellin obtained by heating of bacterial flagella in the presence of PEG did not require exogenous primer. A possible mechanism of flagellin polymerization in the presence of PEG is discussed.

Bacillus↗
PubMedDate not supplied

[Molecular mechanisms of the biological effects of weak magnetic fields. V. Inactivation in vitro of recombinant Rous sarcoma virus reverse transcriptase under the combined action of weak direct and low-frequency alternating magnetic fields, adjusted to the cyclotron resonance of polar amino acid ions].

The effect of weak direct and alternative magnetic fields adjusted to cyclotron frequencies of ions of polar amino acids leads to a functional inactivation of the recombinant reverse transcriptase of Rous sarcoma virus, which is coupled with the proteolysis of this enzyme.

Amino Acids↗
PubMedDate not supplied

[Effect of weak combined low frequency constant and alternative magnetic fields on intrinsic fluorescence of proteins in aqueous solutions].

It was shown that weak combined static (42 microT) and low-frequency variable (40 nT; 3-5 Hz) magnetic fields change the intensity of intrinsic fluorescence of some proteins (cytochrome c, bovine serum albumin, horseradish peroxidase, alkaline phosphatase). The effect can be interpreted as a change in the conformational state of the protein in water environment by the action of weak magnetic fields. The dynamics of the process, the concentration dependence, the binding of proteins to the fluorescence probe 1,8-ANS after treatment with magnetic fields, the frequency dependence of these reactions, and the dependence of the effect on the presence of the static constituent of the magnetic field were studied. It was shown that the changes in the intrinsic fluorescence of some enzymes (horseradish peroxidase, alkaline phosphatase) are related to changes in their functional activity. It was found that the effect is partially transferred via a solvent (water, 0.01 M NaCl) preliminarily treated with magnetic field. In the solvent, changes in its intrinsic fluorescence by the action of weak magnetic fields were also registered.

Alkaline Phosphatase↗
PubMedDate not supplied

[Effect of treated with weak magnetic field aqueous salt solutions on the intrinsic fluorescence of bovine serum albumin. Isolation from solutions and partial characterization of the biologically active fluorescing fraction].

It was shown that water with additions of Ca2+, Na+, K+ and Cl- ions preliminarily treated with weak combined constant (42 microT) and low-frequency alternating (0.06 microT) magnetic fields affects the intrinsic fluorescence of bovine serum albumin, the magnitude of the effect being dependent on the frequency of the alternating field and ionic composition of the aqueous salt solution. A practically complete transfer of the effect through a small portion of the solution treated with magnetic fields was revealed. It was also found that after magnetic treatment, the solution contains a rather large (molecular mass 700-900 D) and stable molecular associate, which possesses, at least partially, the properties and characteristics inherent in the whole solution that were as acquired as a result of magnetic treatment.

Calcium Chloride↗