[Mechanisms of social behavior of the vertebrate tissue cells: cultural models].

Morphogenetic interactions between cells in the organism are largely reproduced in the cell cultures of various types, in particular, in that of the epitheliocytes and fibroblasts. The cultured cells interact by means of receptors and ligands, which activate intracellular signal systems. Three microenvironment components (liquid medium, extracellular matrix, and intercellular contacts) play the role of such ligands. The ligands of liquid medium include hormones, growth factors, apoptosis factors and other molecules. Specific structures strongly tied with the cytoskeleton (with the actin one, first of all) use to appear during contacts with other cells and with the cellular base. Encounter between two fibroblasts or between two epitheliocytes causes local inhibiting of pseudopodial activity (so called contact paralysis). Regeneration of the connective tissue and the epithelial layer, as well as epithelial-mesenchimal transformation, is successfully reproduced in the cell culture. Incomplete epithelial-mesenchimal transformation seems to serve as a base for morphogenesis of various glands and lungs, as well as of angiogenesis.

Morphogenetic response of cultured normal and transformed fibroblasts, and epitheliocytes, to a cylindrical substratum surface. Possible role for the actin filament bundle pattern.

Morphometric characteristics such as cell area, dispersion, elongation and orientation were studied in normal and transformed fibroblasts, and in epitheliocytes cultured on flat or cylindrical substrata. Cylindrical surfaces with a high degree of curvature (12-13 or 25 microns radii) were shown to affect cell size, shape and alignment. The reaction of the cells to the curvature of cylindrical substrata was different in various cell types studied and depended on the pattern of actin microfilament bundles. The cells containing pronounced straight actin bundles (mouse embryo fibroblasts at the polarization stage of spreading, single spread cells of the 'normal' epithelial FBT line or the fully transformed epithelial IAR 6-1 line) were relatively resistant to bending around a cylindrical substratum, and became elongated and oriented along the cylinder. Cells with circular actin bundles as the predominant pattern (mouse embryo fibroblasts at the radial stage of spreading, single spread cells of 'normal' epithelial IAR 20 line) and cells with insufficient or no actin bundles (transformed fibroblastic L line) were prone to bending around a cylinder with much less pronounced elongation and orientation along its axis. The data obtained indicate that the reaction of cultured cells to the geometry of the substratum surface and, in particular, to a cylindrical surface is determined not only by the presence or absence of actin microfilament bundles but by their pattern in the cell.

[The differential diagnosis of Kozhevnikov's epilepsy]. / Differentsial'naia diagnostika épilepsii Kozhevnikova.

Based on the data of a comprehensive examination of 40 patients with Kozhevnikov's epilepsy, 24 with hyperkinesis epilepsy (Sokolianskii-Kliuchikov syndrome), 10 with myoclonus epilepsy (Unverricht-Lundborg syndrome) and 6 with cerebellar myoclonic dyssynergy, the most informative differential diagnostic criteria were distinguished. Their use will make it possible to determine one or another above-indicated disease entity more reliably. The structure of the paroxysmal syndrome and the character of myoclonic hyperkinesis are determined by dissimilar involvement into the pathological process of the cortical, subcortical, stem and cerebellar structures.

[Differential diagnosis of subarachnoid hemorrhage]. / Differentsial'naia diagnostika subarakhnoidal'nogo krovoizliianiia.

Differential diagnosis (DD) of subarachnoidal hemorrhage (SH) should be carried out in two directions: (1) syndromic and nosological and (2) etiological. The diagnosis of 739 verified cases of SH of different etiology was analyzed. The data on DD of SH were systematized, with specification of the concrete disease entities which are to undergo DD. The portion of each of the disease entities was defined, the DD criteria for SH of different etiology were distinguished and tabulated.

Distribution of platelets on flat substrata.

Rabbit platelets attached at a high density to flat glass were examined in a scanning electron microscope. Contours of neighbouring well-spread platelets were almost parallel to each other; overlapping of the edges of two cells were small and rare. Quantitative analysis has shown that overlappings actually observed were much smaller in area that those calculated on the basis of the assumption that platelets are randomly distributed on the substratum. Thus, contact inhibition of spreading is characteristic not only of nucleated cells but also of platelets.

[Estimation of the randomness of the overlapping of cellular structures]. / Otsenka sluchainosti perekryvaniia kletochnykh struktur.

Methods for estimation of randomness of mutual overlaps of cells, their parts, and intracellular structures are developed. Two methods are proposed: a "method of areas" based on the estimation of the area of overlaps of randomly located figures, and a "method of contours" based on the evaluation of the number of intersections of linear structures located randomly. Examples are given as applied to cells and cellular nuclei, in particular during contact inhibition of cellular movement.

[Contact interactions of spreading thrombocytes]. / Kontaktnye vzaimodeistviia rasplastyvaiushchikhsia trombotsitov.

Contact interactions of rabbit platelets was studied in the course of their spreading over the siliconized glass surface. When the density of cells adhered to the substratum surface is high enough, the platelets are spreading in such a way that their edges are in a close proximity, while the overlapping of cells is very rare and scarcely pronounced. A morphometric analysis of the probability of such an organization of platelets at their random and independent disposition on the substratum proves the existence of a contact inhibition of platelets spreading on the substratum. Thus, a phenomenon of the contact inhibition seems to be a common feature not only of large nucleated cells but also of small anuclear platelets.

[Variants in the onset and development of the clinical manifestations of brain tumors]. / Varianty debiuta i razvitiia klinicheskikh proiavlenii opukholi golovnogo mozga.

A retrospective analysis of clinical manifestations of verified brain tumors in 1542 patients showed that the onset of the disease was acute in 5.8%, subacute in 12.3% and gradual in 81.9% while its further course was progressing in 60.5%, progression in 26.9%, remittent in 10.4% and even relatively stable in 2.2%. In 70.4% of the cases the brain tumor developed according to the classic "blastomatous" variant while in the remaining cases it developed atypically, i. e., as an inflammatory (13.1%) or vascular (10.7%) cerebral process, epilepsy (3.3%) or the syndrome of intracranial hypertension without focal symptoms (2.5%). or the syndrome of intracranial hypertension without focal symptoms (2.5%).

[Diencephalic disorders in the acute period of cerebral aneurysm rupture]. / Diéntsef'nye narusheniia v ostrom periode razryva anevrizm sosudov golovnogo mozga.

On the basis of a special study (diencephalic tests and the EEG) carried out in 48 patients with verified intracranial aneurysms the character of the diencephalic disturbances in the acute period of aneurysm rupture was specified. Two forms of the disturbances, i. e. the clinical (in 94% of the patients) and the latent (in 6%) ones, as well as variants of the diencephalic syndrome (vasomotor, catabolic, neurodystrophic and mixed) were differentiated. It is suggested that the development of the diencephalic disturbances in the acute period of rupture of arterial aneurysms is of a stage character.

Behaviour of normal and neoplastic rat cells on grooved substrates.

The distribution and shape of rat cells cultivated on plastic surfaces containing cylindrical areas of various radii and grooves of various depths were studied. Normal embryo cells and two lines of neoplastic cells (LW13K2 and RsK4) were used. The nuclear shape, orientation of the nuclei and migration of cells from the bottom of the grooves were assessed by quantitative methods. All characteristics of the behaviour of both neoplastic cell lines on the grooved substrates were found to be different from those of normal cells: a) the nuclei of neoplastic cells, in contrast to those of the normal ones, did not undergo additional elongation on the cylindrical areas of the substrate; b) the orientation of neoplastic cells with regard to the axis of the cylindrical substrate was decreased or absent; c) the migration of neoplastic cells from certain types of the grooves was decreased. It is suggested that the different reaction to the geometry of the substrate may be a characteristic feature of transformed cells. Possible mechanisms of these alterations are discussed.

Changes in the "shape reaction" and "orientation reaction" of cell nuclei as a consequence of neoplastic transformation. / Izmeneniia "reaktsii formy" i "reaktsii orientatsii" kletochnykh iader vsledstvie neoplasticheskoi transformatsii.

Reactions of cell nuclei on curvature of cylindrical surfaces (curvature radii 333, 75 or 61 mcm) in 9 lines of cultured transformed human, Syrian hamster, rat and murine fibroblasts were studied quantitatively. The nuclear elongation was assessed as a ratio of long to short axes. Contact orientation was characterized by values derived from the angles, formed by long nuclear axes with the direction of cylinder axis. Due to transformation, cells lost the ability to elongate their nuclei in response to cultivation on cylindrical surfaces. The ability of cells cultured on cylindrical surfaces to increase the contact orientation values was also lost or weakened considerably.

[Effect of a number of metabolic inhibitors and other biologically active substances on the development of sea urchin embryos]. / Vliianie riada metabolicheskikh ingibitorov i drugikh biologicheski aktivnykh veshchestv na razvitie zarodyshei morskogo ezha.

Benzo(a)pyrene, hydrocortisone, corticosterone, ethidium bromide, actinomycin D and papaverin arrested the development of sea urchin embryos at the stage of early gastrula when the synthesis of rRNA increases. The fertilization membrane did not prevent the penetration of hydrocortisone and benzo(a)pyrene in the embryo cells. These drugs did not affect RNA synthesis at the early stages of development and markedly suppressed it at the early gastrula stage. A suggestion is put forward to the effect that the developmental arrest at the early gastrula stage is connected with the suppression of rRNA synthesis. The mechanism of selective sensitivity of rRNA synthesis to a wide range of biologically active substances is discussed.

[Shape and orientation of nuclei of embryonal fibroblast-like cells cultured on substrates with ordered relief]. / Forma i orientatsiia iader émbrional'nykh fibroblastopodobnykh kletok na podlozhkakh s uporiadochennym rel'efom

Embryo fibroblasts of hamster, rat, mouse, and were cultured 24 hrs on polyvinylchloride plates with regular relief of grooves with cylindric surfaces in between. Most cells were accumulated on the middle part of spaces between the grooves, their nuclei were elongated and oriented in the direction of grooves. Nuclear elongation was assessed quantitatively by the ratio of long to short nuclear axes. Contact orientation was measured as deviation of the long nuclear axes from the grooves direction. Both contact orientation and elongation considered respectively as "orientation reaction" is maximal and the "form reaction", increased with increasing cylinder curvature (i. e. when the radii diminished from 333 to 61 mcm). Both reactions are well expressed in cultures of the human and (less distinctly) the rat cells. In murine cells, the "orientation reaction" is maximal and the "form reaction" is weak while for the hamster cells the opposite is true. Therefore, both types of reaction seem to be independent characteristics of cells.