[Molecular nature of regulating cell division and differentiation in an organism]. / O molekuliarnoi prirode reguliatsii deleniia i differentsirovki kletok v organizme.

A short review of the investigations of contactins, tissue-specific compounds providing intercellular contacts, which were discovered by the authors in the 60s, is presented.

[Behavior of magnetic particles of metallic iron in animals]. / Povedenie magnitnykh chastits metallicheskogo zheleza v organizme zhivotnykh.

Intraperitoneal introduction of 5-8 mu ferromagnetic iron particles into mouse leads to their capsulation in the liver and preservation in the organism during no less than 1 month. We have observed activation of peroxide lipid oxidation during 3-4 days after the introduction of particles and a two-fold increase of the free iron content in the liver. Intraperitoneal introduction of ferromagnetic particles with diameter below 1 mu produced rapid death. Intravenous injection of 5-8 mu diameter ferromagnetic particles into rat resulted in their accumulation in the liver, lung and spleen, probably due to the absorption of the iron particles by macrophages. In two weeks these particles were transformed and vanished from the tissues.

[Stability threshold of a tissue system]. / O poroge ustoichivosti tkanevoi sistemy.

Studies of changes in the cells adhesive force during spontaneous and induced cancerogenesis, as well as under the effect of cancerogenesis promotors permits to reveal the cells adhesion forces critical values which separate tissue states stable and unstable to blastomogenesis. These data are analysed proceeding from the concepts on generalized cooperative transitions in the membranes and their role in the control over biological systems. It is taken into account that the membranes and cytoskeleton elements are the most important systems of the tissue mechanical integration, and phase transitions proceeding in them must be reflected in the tissue mechanical properties.

[Action of carcinogenesis promoters on the adhesive force of cells in the liver, lung and thyroid gland in rats and mice]. / Deistvie promotorov kantserogeneza na silu stsepleniia kletok pecheni, legkikh i shchitovidnoi zhelezy u krys i myshei.

The short-term effects of the carcinogenesis promoters on the adhesive force of cells are compared with the data from literature on their ability to exert a promoter action on the carcinogenesis development in the same organs during prolonged introduction after an initiator. The ability of substances to decrease the adhesive force in the tissue below the resistance threshold is established to correlate with its promoter activity. The coincidence of tissue specificity of both effects and active doses of substances is observed.

[Physical basis for the application of ferromagnetics introduced into body]. / Fizicheskie osnovy primeneniia ferromagnetikov, vvedennykh v organizm.

The review deals with some medico-biological problems of ferromagnetics applications with the use of physical fields effect (permanent and alternating magnetic fields, high frequency and laser radiation). The main aspects are the following: magnetic fluid as roentgenocontrast, substances; magnetically controlled drug delivery systems; magnetic microspheres with immobilized antibodies; thermo-magnetic cancer surgery; magnetic particles as a tool for subcellular structure investigation; magnetic particles distribution and removal from the organism.

[The nature of transepithelial potential of the liver]. / O prirode transépitelial'nogo potentsiala pecheni.

The method of continuous monitoring of rat liver transepithelial electrical potential in situ (the potential between electrodes inserted into the common bile duct and blood flow) with simultaneous measurement of liver blood filling by photoelectroplethysmography is described. It was suggested that spontaneous oscillations of potential value with the period 20-30 sec found in the experiment were associated with synchronous oscillations of blood vessels and bile ducts cross section square caused by synchronization of pre- and postcapillary sphincters activity.

[Integral characteristics of heat- and electroconductivity of human skin]. / Integral'nye kharakteristiki teplo- i élektroprovodnosti kozhi cheloveka.

Age relationships of integral parameters of heat- and electroconductivity (HC and EC) of human skin were studied. Measurements were performed in 14 body regions (Zakharyin-Gedd zones and opposite points) on 95 practically healthy women 10-63 years old. Cluster analysis of the experimental data has shown that population is evenly distributed in the space of characters. The correlation analysis permits the statement that HC and EC are practically independent parameters. At the same time the correlation coefficients for HC and EC values obtained in the opposite points are rather high. Therefore the integral parameters were introduced for describing the system: mean values (EC and HC), indices of lateral asymmetry IAEC and IAHC), nonhomogeneity indices (NIEC and NIHC). Age relationships of integral parameters and their root-mean-square deviations were computed using smoothing by the moving-average method with Gaussian weight function, whose width was optimized by the minimum of information losses. For EC and NIEC and for root-mean-square deviations of IAHC and NIHC statistically reliable changes with age are observed. They reflect the physiological state of the organism (EC and NIEC being of the leading character). The indicated integral parameters are suggested to be used for estimating the man's state at hormonal reconstructions of the organism.

[The nature and biological role of near-weekly rhythm]. / O prirode i biologicheskom znachenii okolonedel'nogo ritma.

Main peculiarities and possible mechanisms of the rhythms of proliferative activity and other characteristics of the tissue with near-weekly period are discussed. It is suggested that these variations may be explained by means of a simplest model which involves only processes of cell division and death with a delay of division stimulus about 24 hours, which corresponds to the duration of the mitotic cycle. In such a model there are periodic variations of the cell number with the period 4-7 times greater than the delay time.

[A system of mechanical integration of tissue as the basic regulation system at the tissue level of organization]. / Sistema mekhanicheskoi integratsii tkani--osnovnaia upravliaiushchaia sistema tkanevogo urovnia organizatsii.

A new concept for tissue--level regulation system is proposed. This concept is based on three groups of facts: 1) possibility of regulation of tissue behavior by fields of mechanical tension; 2) correlation between changes in mechanical properties of the tissue and its biological behavior at different stages of blastomogenesis; 3) regulative role of tissue--specific (endo- and exo)-genic factors which influence directly the mechanical properties of the tissue. This system is called the system of the mechanical integration of the tissue. Some problems concerning the action mechanism of this system are discussed.

[Effect of hemodynamic disorders on the transepithelial potential of the rat liver in vivo]. / Vliianie gemodinamicheskikh narushenii na transépitelial'nyi potentsial pecheni krys in vivo.

The presence of transepithelial electrical potential (TEP) formed on the border between the interstitium and the interior of the rat liver bile capillary has been demonstrated. The initial TEP value (II+ 3 mV) reduced rapidly to zero after the ligation of different portal fissure vessels, while ischemia arrest led to TEP restoration. True periodical oscillations of TEP value with the period and amplitude of about 30 s and 1-2 mV, respectively, were registered. These oscillations appeared in all cases of liver ischemia 5-7 min after ischemia removal and lingered till the end of the experiment. It was assumed that variations in TEP and membrane potential of hepatocytes have the common nature.

[Transformation of ferromagnetic suspensions in the animal body]. / Prevrashchenie ferromagnitnykh suspenzii v organizme zhivotnykh.

Ferromagnetic suspension (FS) was introduced into rat and mouse organisms by different ways. Transformation of FS into some organs was estimated by ESR-method within the temperature region 80-250 K. It was shown that FS introduced in the animal organism was utilized in it very quickly.

[Cell surface RNA--a possible molecular receptor of adaptogens]. / RNK poverkhnosti kletok--vozmozhnyi molekuliarnyi retseptor adaptogenov.

When RNA of the cell surface is destroyed with RNAase, the effect of adaptogenes is removed. Such effect is produced by introduction of actinomycin D 30 minutes before intake of adaptogene. Destruction of surface RNA stimulates protein synthesis. Comparison of these facts permits a hypothesis to be advanced saying that surface RNA is a receptor of adaptogenes obtained from plants of Aralia family.

[Prolonged changes in hormonal homeostasis after brief circulatory arrest in the small intestine]. / Dlitel'nye izmeneniia gormonal'nogo gomeostaza posle kratkovremennoi ostanovki krovoobrashcheniia v tonkoi kishke.

It has been established that temporary cessation of blood circulation in the rat small intestine induces alterations in the levels of thyroid and glucocorticoid hormones. These alterations are of the wavy character and can be traced up to 2 weeks after the operation that correlates with duration of previously found functional biochemical, and morphological changes.

[Trigger mechanisms for cell division in vivo]. / Ob osobennostiakh puskovykh mekhanizmov deleniia kletok in vivo.

A model of stimulating liver regeneration by temporary ligation of selected branches of the hepatic blood vessels was developed in the experiments on rats. For initiating compensatory hypertrophy of the liver it is necessary to compress the portal vessels of the left hepatic lobes up to 20--22 hours, that is until the cells entry into the S-phase. A suggestion was put forward about the differences of stimulation of cell division in the in vivo and in vitro systems.

[Nature of the membrane potential of liver cells]. / O prirode membrannogo potentsiala kletok pecheni.

Light scattering (90 degrees) of Ehrlich ascites tumor and sarcoma 37 cell suspension in the temperature range 25,60 degrees C was studied (heating velocity was 3 grad/min). It is found that the scattering curve has the peak at 46 degrees C and two plots which are typical of phase transitions in the membranes; the first plot in the range 40-46 degrees C is reversible and the second one at 46-51 degrees C is irreversible. It is proposed that 46 degrees is a critical temperature for the membranes structure stability and viability of the studied cells.

[Effect of hepatic adhesion factor, contactin, on the mechanical properties of ultrastructural elements of hepatocyte contact]. / Vliianie adgezionnogo faktora pecheni--kontaktina na mekhanicheskie svoistva ul'trastrukturnykh élementov kontakta gepatotsitov.

Injection of isotonic fluid under heightened pressure 20--30 mm of Hg into the bed of the liver reveals inhomogeneity of the mechanical properties of the simple junction of heptacytes: the zone where the divergence of the contact surfaces is observed is interrupted by highly adhesive regions (HAR) where the normal distance between the membranes is preserved. The adhesive factor acts as an organizer of the inhomogeneity of the simple junction: when it is introduced in vivo, new HAR appear in the simple junction. On account of contact-tropic activity of adhesive factor we termed it--contactin.