Effect of viral preinfection upon cell adherence in some staphylococcus strains from specific infections or carriers.

The adherence of bacteria to eukaryote cells has been largely investigated as an essential step in the occurrence of bacterial infection. Some clinical and epidemiological studies have revealed the frequent association of certain viral infections with bacterial infections originating in the same ecological niche. Therefore, we investigated the effect of the viral preinfection (ADV4) of some cultivated cells (HEp-2 and IC.

Reactivity of HeLa tumoral cells under the in vitro action of some aromatic compounds from the phytomass.

The in vitro action of some natural polyphenolic preparations, extracted from the leaves of Asclepias syriaca, upon the proteinosynthesis of HeLa cancerous cells and, implicitly, upon the development of HeLa cells cultures was investigated. The significant perturbation of proteic biogenesis, the inhibition of HeLa tumoral cells cultures development, as well as the existence of a dose--response relationship argue the behaviour of these products as in vitro active cytostatic agents. This characterization justifies their introduction in the in vivo screening program on rats bearing of different experimental tumoral lines, for the preclinical pharmacological evaluation of the POLYAS I and POLYAS II vegetable polyphenols antineoplastic activity.

Effect of prostaglandin E2 (PGE2) and cyclic adenosine monophosphate (cAMP) upon actin cytoskeleton in human pulmonary fibroblasts (ICP-23) infected by measles virus.

The evolution of the actin cytoskeleton after trypsinization and recultivation as well as the effect of the PGE2 modulator and that of the secondary messenger, the cyclic AMP upon the same cytoskeletal proteins in human pulmonary fibroblasts (ICP-23) were studied. The substances were administered simultaneously and after one hour of viral adsorption. Using epifluorescence for pointing out filamentous actin the modifications occurring in this cytoskeletal protein when contacting trypsin and the virus and when PGE2 and cAMP are administered in the experimental variants are observed.

Adaptation of the herpetic virus on human diploid and monkey kidney cells.

Viral suspensions of herpetic virus were inoculated on different cell cultures: human diploid cells (HDC) and monkey kidney cells--primary culture and cell line--for adapting the virus on these cells and obtaining several high constant titers. The human diploid cells and the monkey kidney cell line have proved to be the most suitable cells for the virus growth; thus an optimum development of the virus with a high constant titer was obtained starting with the 4th passage (10(5.7)-10(6)CPD/50/ml).

The anti-initiator action of p-methoxyphenol phosphate upon the transformation of normal human embryo cells induced by benzo(a)pyrene.

The association of p-methoxyphenol phosphate (10(-5)M) to benzo(a)pyrene treatment (10(-6)M) reduced significantly the anchorage independent growth and the number of transformed foci of the human embryo lung fibroblasts, after six passages from treatment application. Results from cytogenetic analysis show that p-methoxyphenol phosphate induced the decrease of numerical and structural chromosome aberration after the first passage of the treated cells. In terms of the results obtained by cytogenetic analysis the reduction of genetic instability seems to remain constant from the first to the sixth passage in the cell cultures treated with p-methoxyphenol phosphate associated to benzo(a)pyrene.

Prostaglandin E2 (PGE2) effect upon ICP-23 human pulmonary fibroblasts growth in culture and on measles virus multiplication in this cell type.

The influence of PGE2 in different concentrations (10(-4)M, 10(-6)M, 10(-8)M) and of 1 mM AMPc upon ICP-23 human pulmonary fibroblasts and also the influence of PGE2 upon measles virus multiplication in the same cell type were studied. PGE2 inhibited fibroblasts growth in all administered concentrations, depending on them. AMPc adding to human fibroblasts in culture progressively stimulated cells growth in the first 24 hours, produced a steady growth during 24-48-hour interval and slightly inhibited cellular divisions between 48 and 72 hours.

In vitro effects of pulsed near-ultraviolet laser exposure on human larynx carcinoma cells.

Effects of pulsed near-ultraviolet laser beam on structural characteristics and macromolecular synthesis of carcinoma HEp2 cells were investigated. Laser irradiation damage induced in these eukaryotic cells could be characterized by two development stages: a) a reversible stage with minor morphological damages (1.5 kJ/m2) and 2) an irreversible one, at higher fluences, characterized by cellular membrane damage, necrobiosis and cells detachment from the substrate (4.

Laser effects on cellular adhesion and influence on the interrelation between HeLa S3 and human diploid cells.

The interactions between HeLa S3 tumoral cells and human fibroblasts after nitrogen-laser irradiation (337.1 nm) have been studied by using an in vitro cell invasion model. For the quantitative and morphological evaluation of nitrogen-laser radiation action upon tumoral adhesion to the fibroblast monostrate, we used: a) 3H-thymidine labelling of HeLa S3 tumoral cells; b) morphological modifications studies by phase contrast and scanning electron microscopy.

The protective effect of Thiola against the genotoxic action of benzo(a)pyrene.

The protective effect of Thiola against the genotoxicity, induced by benzo(a)pyrene, in vitro and in vivo, was investigated. By association of Thiola to benzo(a)pyrene a significant decrease of the numerical and structural chromosome aberrations and a reduction of the incidence of c-mitoses has been obtained in human diploid cells, i.e.

Some characteristics of the ICCe-1, a new simian embryo cell line.

A new simian embryo cell line has been established from a Cercopithecus male whole embryo. The resultant predominant fibroblast-like cell population has been frozen in convenient quantities and characterized for use in biological research as well as in theoretical and practical virological purposes. The cell line was designated ICCe-1 (Institute Cantacuzino Cercopithecus embryo-1).