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F Rosskopf

Publications and source records attributed to F Rosskopf.

4 recordsLinked to original sources
PubMed1992

Antitumour and immunological activity of a beta 1----3/1----6 glucan from Glomerella cingulata.

The in vivo antitumour activity of a beta 1----3/1----6 glucan from the fungus Glomerella cingulata was investigated in vivo. The glucan exhibited a strong inhibition of tumour growth of the allogeneic Sarcoma-180 as well as the syngeneic DBA/2-MC.SC-1 fibrosarcoma with inhibition ratios up to 100%. Against the hormone sensitive Noble-Nb-R prostate carcinoma the glucan alone showed a moderate antitumour effect, whereas in combination with diethylstilbestrol an almost complete regression of the tumour could be achieved. It could be demonstrated that a highly ordered structure of the glucan is not essential for the antitumour activity. Since the glucan expressed no direct cytotoxic effects, the immunomodulating activity was investigated in vitro in order to get an indication for a possible mode of action. In the lymphocyte transformation assay the glucan at a dose of 100 micrograms/ml caused a fourfold increase in the proliferation of murine spleen lymphocytes. Moreover, the glucan stimulated the phagocytosis of zymosan by bone marrow macrophages up to 100%. However, the glucan was not able to render macrophages cytotoxic against P-815 mastocytoma cells.

Animals↗
PubMed1992

Immunological and antitumor effects of coumarin and some derivatives.

Coumarin and its 4-OH and 7-OH derivatives, as well as o-, m- and p-coumaric acid were tested against P-815 and P-388 tumor cells in vitro. In addition, the compounds were investigated in various in vitro immunological test systems and genuine coumarin was tested furthermore against the Sarcoma-180 in CD1 mice. In vivo, coumarin showed only a moderate antitumor effect against the allogeneic Sarcoma-180 at concentrations of 10 and 40 mg/kg, with inhibition rates of 49 and 60%, respectively. However, both concentrations were markedly toxic. In vitro all compounds were more or less cytotoxic against P-815 and P-388 tumor cell lines starting at a concentration of 100 micrograms/ml. At subtoxic concentrations (less than or equal to 10 micrograms/ml) the samples showed no mitogenic activity against murine spleen lymphocytes and PHA costimulated human peripheral blood lymphocytes. Furthermore, with the coumarin derivatives neither cytotoxic macrophages could be induced against P-815 tumor cells nor an increased release of Il-2 and TNF-alpha could be observed. Only 7-OH coumarin, in concentrations of 2 and 20 micrograms/ml, caused a strong increase in phagocytosis of 124 and 84% in both, human peripheral blood granulocytes and murine peritoneal macrophages, respectively.

Animals↗
PubMed1991

[Polysaccharides from Nerium oleander: structure and biological activity].

A water extraction of crushed leaves of Nerium oleander yielded 2.3% of a crude polysaccharide. The main fraction (67%) represents a pectic polysaccharide mainly composed of galacturonic acid besides rhamnose, arabinose and galactose. The polysaccharide structure was characterized by NMR, mild acid- and pectinase treatment combined with GC-MS analyses. In vivo tests for a possible antitumor activity did not result in a significant action. Investigation of immunomodulating activity brought some indications for mitogenic activity and a weak macrophage-mediated cytotoxicity. Increase of phagocytosis could not be doubtlessly assigned to the polysaccharide due to the high amount of endotoxin in the homogenous fraction OLE 2.

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