Quantitative cytochemical analysis by microdensitometry of spontaneous or alpha-MSH-stimulated melanogenesis in B16 melanoma cells cultivated in vitro

in European Journal of Cancer & Clinical Oncology (1985), 21(8), 951-956

Spontaneous and alpha-MSH stimulated melanogenesis has been studied in B16 cells by densitometry. De novo synthesis of the enzyme dopa-oxydase takes place following alpha-MSH treatment.

Mechanism of action of free or incorporated into liposomes cis-DDPt : a comparative study in Ehrlich tumour cells

in Hacher, M. P.; Douple, F. B.; Krakoff, I. M. (Eds.) Platinum Coordination Complexes in Cancer Chemotherapy (1984)

Effects of gold compounds, free or incorporated in liposomes, on human synovial cells in culture

in Archives de Biologie (1984), 95(4), 413-21

Two gold compounds with anti-inflammatory action are separately introduced into fluid negative liposomes : Aurol-sulfide (colloidal gold compound) into the aqueous phase of liposomes, Auranofin (soluble ... [more ▼]

Two gold compounds with anti-inflammatory action are separately introduced into fluid negative liposomes : Aurol-sulfide (colloidal gold compound) into the aqueous phase of liposomes, Auranofin (soluble organic compound) into the lipidic phase. Their effects are analysed in synovial cells in culture. Aurol-sulfide, given alone, rapidly enters into the cells where it is found inside membrane limited inclusions. Under our experimental conditions, this agent is atoxic and has no effect on the cell cycle. When transported inside liposomes, Aurol-sulfide is found free, at least in part, in the cytoplasm and rapidly induces cell degeneration. Auranofin, given alone, is very cytotoxic under some experimental conditions. On the contrary, synovial cells are less sensitive to Auranofin whe encapsulated in liposomes. [less ▲]

Alteration in the nucleosome and chromatin structures upon interaction with platinum coordination complexes

in Biochimica et Biophysica Acta-Gene Structure and Expression (1983), 739(3), 317-25

The interaction of various platinum coordination complexes with nucleosomes and chromatin has been investigated by ultraviolet absorption spectrophotometry, circular and electric linear dichroism, and ... [more ▼]

The interaction of various platinum coordination complexes with nucleosomes and chromatin has been investigated by ultraviolet absorption spectrophotometry, circular and electric linear dichroism, and thermal denaturation, at low binding ratios (r < 0.1–0.2). The general trend of the changes in these physicochemical properties is similar to that observed for the DNA-platinum complexes, which indicates that the same binding sites are involved in the platinum interaction with DNA and with its nucleoprotein complex. The cis-bidentate ligands, cis-dichlorodiammine, diaminocyclohexane and ethylenediamine platinum(II), showed a distinct behavior, with a more important destabilization of the DNA structure in the nucleoprotein than the trans-bidentate ligand, trans-dichlorodiammine-Pt(II), and monodentate ligand, diethylenetriamine-Pt(II). The drastic decrease of the negative electric dichroism in the 260 nm absorption band of the bases, observed with the five ligands, indicates a profound alteration of the DNA arrangement in chromatin and nucleosomes, attributed to a condensation of its superhelical structure. Some differences with previous observations on DNA complexes with the same platinum compounds indicate the possible formation of protein-DNA crosslinks in chromatin and nucleosomes. These could have some importance for the biological effects. [less ▲]

Effets de trois Alcaloides Extraits du Strychnos usambarensis sur des Cellules Cancereuses en Culture

in Planta Medica (1982), 45(6), 123-6

The cellular effects of three alkaloids isolated from STRYCHNOS USAMBARENSIS (melinonine F, strychnofoline, 18-19-dihydro-usambarine) are analysed by cytological methods in experimental animal tumours ... [more ▼]

The cellular effects of three alkaloids isolated from STRYCHNOS USAMBARENSIS (melinonine F, strychnofoline, 18-19-dihydro-usambarine) are analysed by cytological methods in experimental animal tumours cultivated IN VITRO (B 16 mouse melanoma cells, mouse Ehrlich tumour cells ELT, HW 165 rat hepatoma). Under some experimental conditions, a certain degree of antimitotic activity is demonstrated. [less ▲]

La melanogenese, expression de la differenciation de cellules cancereuses en culture

in Bulletin de l'Association des Anatomistes (1982), 66(194), 291-295

In B16 mouse melanoma in culture, differentiated cells actively synthesize melanin. They are analyzed by cytological and cytochemical methods. When cultured for long periods (several months ... [more ▼]

In B16 mouse melanoma in culture, differentiated cells actively synthesize melanin. They are analyzed by cytological and cytochemical methods. When cultured for long periods (several months), melanogenesis is expressed according to a cyclic way, even when maintained in a culture medium of constant composition and without adding any chemical agent eventually able to influence this phenomenon. The spontaneous cyclic activity is analyseed and an explanation is given as an hypothesis. [less ▲]

Modulation of melanogenesis of B16 melanoma cells in culture

Conference (1981, May)

Scanning electron microscopic study on the interaction of liposomes with cells in vitro

in European Journal of Cell Biology (1980), 22

Biomedical application of PIXE in University of LIEGE

in Nuclear Instruments and Methods (1980), 168

Three biomedical applications of charged particle induced X-ray emission spectroscopy (PIXE) are outlined. The different fields investigated include biophysics (protein study), cancer chemotherapy (cis ... [more ▼]

Three biomedical applications of charged particle induced X-ray emission spectroscopy (PIXE) are outlined. The different fields investigated include biophysics (protein study), cancer chemotherapy (cis-dichlorodiamineplatinum (II) associated to liposomes as carriers) and lung pathology (serum and bronchio-alveolar lavages). The samples were irradiated with 3 Me V protons (cyclotron) in a nitrogen atmosphere. [less ▲]

Interaction of DNA and purine nucleosides with cis-dichlorodiammineplatinum(II) and antimitotic activity of the complexes on meristematic root cells

in Chemico-Biological Interactions (1979), 25