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V L Livshits

Publications and source records attributed to V L Livshits.

14 recordsLinked to original sources

[Ultrastructural anomalies of the desmosomal contacts in monolayer transformed cultures].

The ultrastructure of cell-cell desmosomal contacts and their cytoskeletal components in the cellular monolayer of transformed epithelial cultures is studied. It is suggested that asymmetry of the desmosomal contact formation, the formation of hemidesmosome-like structures on the lateral surface of one of the contacted cells and defects of cytoskeletal desmosomal components are related to transformational changes in the functionally different contacted cells.

Animals↗

[Ultrastructure of L-line lipoblast-like cells during cloning in a medium with a high serum concentration].

The ultrastructure of lipoblast-like cells produced by clones of transformed culture of strain in the medium with an increased (60%) concentration of bovine serum was studied. The aim of using the stimulator rich in adipogenous factors was the elucidation of the origin of lipid accumulation in some of cell types during heterogeneous differentiation of clones. In these conditions non-differentiated lipoblasts assumed the fine structure of mature lipid cells. The statement of the marker significance of lipid accumulation in non-differentiated cells of the clones and the conversion of these cells under the influence of non-specific stimulator to the mature lipocytes confirms the data on conservation of over-all cytogenetic potentials and the capacity of their realization in the cells of transformed cultures. It is suggested that the increased concentration of bovine serum in the cultural medium not only stimulates differentiation (by any way determined cells), but is also capable of acting on the stem elements produced by the clone. In that case the influence of the stimulator on the trends of heterogeneous differentiation is not unlikely.

Adipose Tissue↗

[Cellular ultrastructure of a cloned L-line culture].

A study of the fine structure of cells obtained from the transformed cloned culture of strain L, that have developed from a single cell, demonstrated several different cell types. The clones contained both non-differentiated and poorly-differentiated cells. The presence of morphotypical signs in the poorly-differentiated cells allowed to reveal some cell clone types and the direction of their specialization process. The study confirms the idea on the presence of the stem cell elements in the transformed cell culture of strain L causing the heterogenous way of cytodifferentiation and determining the long-term stability of cell polymorphism in this cell strain.

Animals↗

[L line cell differentiation. Histochemical and electron microscopic studies].

In a medium supplemented with 60 per cent large cattle serum, part of the cell population of L-transformed culture was seen to be differentiated into mature lipocytes. The formation of structures similar to normal fat tissue took place in the same conditions, provided a reduced quantity of the seeded cells was used. The cell differentiation was accompanied with a decrease in acid phosphatase and non-specific esterase activities. The ultrastructural study has demonstrated a suitable preservation of cytoplasmic structures and a domination of the rough cytoplasmic reticulum compared to the control cell cultures where free ribosomes and polysomes predominated.

Acid Phosphatase↗

[Method of embedding cultures in situ in epoxy resins for comprehensive light and electron microscopic analysis].

A simple method for making preparations for light and electron microscopy analysis both from tissue cultures and other biological objects is proposed. The techniques of in situ flat-parallel embedding in special forms between two layers of polyethylene phthalate (PEPh) film are described. The method makes the maximum use of all the properties of the PEPh film allowing to utilize it as a substrate-support for growing cultures and as a substrate for forming optical properties of the preparations. The preparations so made are suitable for preliminary examinations by light microscopy, photography, and marking the selected areas for subsequent flat and sagital ultratomy.

Cells, Cultured↗

[Effect of chemical carcinogens on the ultrastructure of cultured differentiating myogenic cells].

The electron microscope studies have been carried out on primary monolayer tissue culture obtained from body tissues of rat and C3H mouse embryos. The cells of tissue culture were mainly myoblasts and fibroblast-like cells. The cultures were treated with two different carcinogenic substances--benz(a)-pyrene (BP) and methylnitrosonitroguanidine (MNNG). The changes were uniform and showed some alterations in formation of cell complexes, the inhibition of development and maturing of muscle elements, and distrophy of cytoplasmic organelles. The revealed distinction in morphological reaction of myogenic cells to the effect of BP and MNNG were wave-like myofibrillar structures in MNNG-treated cultures.

Animals↗

[Spot marking of photo-optic preparations intended for ultratomy].

The possibility of a highly precise spot marking of those areas of the tissue which are of interest for the investigator of the group and individual cells revealed during the photo-optic investigation of preparations, is of particular importance for their subsequent ultrastructural studies. However, the markers used new for marking photo-optic preparations, whose effect is based on the principle of delineation and of the area concerned, suffer a number of shortcomings, one of them being the impossibility to variate while marking the geometrical form of the mark on the preparation and to apply to it simultaneously more than one mark. In combined photo-optic and electron-microscopy studies of preparations it would be invaluable to apply a highly precise spot marker capable of applying simultaneously to the preparation two marks differing from each other by their geometrical form. In this case, the process of formation of "pyramid" would have been considerably easier for the investigator during the preparation of the specimen for ultratomy. Exactly this kind of a highly precise spot universal marker based on the principle of stamping has been designed and used by the author.

Histological Techniques↗

[Light microscopic and electron microscopic study of the cells of tissue cultures irradiated with a neodymium laser].

Damage of tissue culture cells (Hela, a human amnion, a primary rat liver culture) caused by the neodymium laser radiation was studied by time-lapse phase-contrast microfilming and electron microscopy. The tested cultures were shown to display different sensitivity and the degree of cell alteration within the same cultures varied considerably. A physical mechanism of cell damage is probably of thermal and shock-wave nature.

Amnion↗