B. Loddo

In vitro guanidino-resistance and guanidino-dependence of poliovirus

Il virus poliomielitico può essere reso,in vitro, guanidino-resistente se propagato serialmente in culture cellulari contenenti dosi crescenti di guanidina. Proseguendo nei passaggi seriali in presenza delle dosi massime di guanidina tollerate dalle cellule, si ottiene un ceppo di polio virus che si sviluppa assai meglio in terreni contenenti la sostanza che non in terreni che ne siano privi. Tale caratteristica, che richiama quella della antibiotico-dipendenza di alcuni schizomiceti, sembra deporre per una autonomia del virus rispetto alla cellula ospite maggiore di quanto sinora ritenuto.

Selective inhibition of poliovirus growth by d-penicillamine in vitro

Abstract d -Penicillamine inhibits poliovirus growth in vitro. This effect is related to a parallel inhibition of viral RNA synthesis. d -Penicillamine possesses a very narrow antiviral spectrum. In fact it exerts a weak inhibition against Coxsackie and ECHO viruses and shows no inhibitory effect against herpes simplex, vaccinia, and vesicular stomatitis viruses. The inhibitory action of d -penicillamine is suppressed by phenylalanine, tyrosine, tryptophan, and leucine and by Cu and Fe salts. l -penicillamine is ineffective as an antiviral agent.

Antagonism of the guanidine interference with poliovirus replication by simple methylated and ethylated compounds

Abstract Simple methylated and ethylated compounds (trimethylamine, tetramethylammonium iodide, methylformate, methylacetate, methanol, triethylamine, tetraethylammonium iodide, choline, hemicholinium HC-3, methionine, ethionine, etc.) are able to inhibit the influence of guanidine on in vitro poliovirus replication either when guanidine acts as a growth inhibitor, or when it acts as a growth-promoting factor. The mechanism by which these compounds antagonize guanidine is not clear. The lack of activity of betaine, with the antiguanidine activity of ethionine, seems to exclude the involvement of known biological methylating systems.

POLIOVIRUS: GUANIDINE DEPENDENCE AND LOSS OF NEUROVIRULENCE FOR MONKEYS.

Guanidine-dependent polioviruses are obtained in vitro by subculturing Brunenders, Mahoney, and Sabin strains in the presence of increasing concentrations of guanidine. Mahoney viruses dependent on guanidine lose virulence (as indicated by paralysis) for monkeys inoculated intramuscularly or intracerebrally. Protection against virulent Mahoney viruses is induced by treatment with guanidine-dependent strains, and serum antibodies against the virulent strains are present in the treated animals

Infective ‘ribonucleic acid’ extraction from poliovirus by sodium dodecylsulfate

Il dodecilsolfato di Sodio (SDS) si è dimostrato capace di estrarre, se fatte o agire a temperature di 65°–90°C, acido ribonucleico infettivo da culture di cellule HeLa infettate con estratte da inocula massivi di poliovirus 1.