0000000000464860
AUTHOR
Armin Maidhof
Untersuchungen zur Desoxyribonucleaseaktivit�t der Haut bei Xeroderma pigmentosum
Die Gesamtaktivitat der neutralen Desoxyribonucleasen (DNasen) in Xeroderma pigmentosum (X.P.) — und in Normalhaut ist gleich. Dagegen ist die Gesamt-DNase-Aktivitat bei pH 5,3 in X.P.-Haut im Vergleich zur Kontrollhaut signifikant geringer.
Polyclonal antibodies to mannan from yeast also recognize the carbohydrate structure of gp120 of the AIDS virus: an approach to raise neutralizing antibodies to HIV-1 infection in vitro.
This study initiates a new method of developing an antigen which might be useful in the prevention of HIV-1 infection. Using a mannan preparation from Saccharomyces cerevisiae neutralizing antiserum was raised in rabbits which prevents HIV-1 infection in vitro up to a titre of 1:128. The corresponding antibody preparation neutralized the in vitro infectivity down to a concentration of 5 micrograms/ml. Analytical studies suggest that the antibodies are directed against the mannose residues of the HIV-1 glycoprotein (gp) 120 and its precursor gp 160.
Inhibition of intrinsic protein tyrosine kinase activity of EGF-receptor kinase complex from human breast cancer cells by the marine sponge metabolite (+)-aeroplysinin-1
1. (+)-Aeroplysinin-1, a naturally occurring tyrosine metabolite from the marine sponge Verongia aerophoba, was found to inhibit the phosphorylation of lipocortin-like proteins by a highly purified preparation of the epidermal growth factor (EGF) receptor-tyrosine protein kinase complex from MCF-7 breast carcinoma cells. 2. (+)-Aeroplysinin-1 blocked the EGF-dependent proliferation of both MCF-7 and ZR-75-1 human breast cancer cells and inhibited the ligand-induced endocytosis of the EGF receptor in vitro. 3. Treatment with aeroplysinin-1 in the concentration range at 0.25-0.5 microM resulted in a time- and dose-dependent total tumor cell death in vitro. 4. At a 10-fold higher concentration…