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E A Modianova

Publications and source records attributed to E A Modianova.

31 records · Page 2Linked to original sources
PubMedDate not supplied

[Stability threshold of a tissue system].

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.

Adenoma↗
PubMedDate not supplied

[A system of mechanical integration of tissue as the basic regulation system at the tissue level of organization].

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.

Animals↗
PubMedDate not supplied

[Effect of hepatic adhesion factor, contactin, on the mechanical properties of ultrastructural elements of hepatocyte contact].

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.

Animals↗
PubMedDate not supplied

[Changes in the intercellular contacts of hepatocytes in the ontogeny of inbred mouse strains with a high (CBA) and low (C57BL) frequency of spontaneous hepatomas].

Some parameters of cellular contacts between hepatocytes were studied in ontogenesis of the inbred mouse lines with the high (CBA) and low (C57BL) frequency of spontaneous hepatomas. In both the lines the force of intercellular linkage of the hepatocytes drops down by the end of the animal's life. But in the C57BL mice this characteristics increases sharply between the 5th and 10th days after birth, whereas in the CBA mice no such increase is observed. During the whole postnatal development the force of linkage in the CBA mouse liver is thrice lower than in the C57BL mouse liver. The stability of contacts between the hepatocytes in the C57BL mice is not affected during ontogenesis, as well as in the CBA mice, except in the males at the age of 15-24 months when the stability of contacts decreases. This parameter decreases still more in the tumour. Since the CBA males are characterized by a higher frequency of spontaneous hepatomas, a suggestion is put forward to the effect that the primary disturbance of the stability of contacts reflects the early changes characteristic for the spontaneous liver carcinogenesis.

Aging↗
PubMedDate not supplied

[The carcinogen urethane induces high-amplitudes circaseptan variations in target tissues and disrupts the rhythm of cell count in lymphoid organs].

The presence of tumor is accompanied by biological rhythms disturbance both in damaged (target) organ, and in nondamaged systems. As discoordination of biorhythms is sometimes one of the causes of pathologic states, we have investigated, which changes in system of about 7-day duration (circaseptan) biorhythms preceded the tumor appearance. The model of lung carcinogenesis, induced by single dose (0.25 mg/g of body weight) of carcinogen urethan in A mice, was used. Characteristics of both target organ, and other organs was studied at the stage, preceding the tumor appearance. The data obtained were compared with the analogous characteristics of the control group, once injected with noncarcinogenic analog of urethan, methylcarbamate. The presence of about 7-day rhythms in several organs, nonsensitive to carcinogenic action of urethan, was demonstrated in the control group. The periods of oscillations were: in bone marrow (the number of nuclear cells)--5.2 days; in thymus (mass; the number of nuclear cells)--7.8, 8.2 days; in liver (mass)--6.2 days; in kidney) mass)--8.9 days; in blood (the number of leukocytes)--10.6 and 4.0 days, ect. In the control lungs low-amplitude rhythm of tissue mechanical characteristics (T = 3.5 days), was revealed (these characteristics indicate the extent to which cells are integrated into tissue). Single carcinogen injection resulted in statistically significant decrease (1.4-1.8 fold) of the periods of the main garmonic in the resistant organs. In lungs (target organ) powerful high-amplitude circaseptan oscillations, not inherent to the lungs of control mice, arise in this tissue after the carcinogen injection.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenal Glands↗