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C WALLIS

Publications and source records attributed to C WALLIS.

At least 37 records · Page 2Linked to original sources
PubMed1962

An aluminum marker for the differentiation and separation of virulent and attenuated polioviruses.

A new character, the A marker, for polioviruses is described. In the presence of Al(+++) (1 to 100 mM) attenuated, but not virulent, strains of type 1 and type 2 polioviruses are stabilized so that they resist thermal inactivation at 50 degrees C. Differences between the attenuated and virulent type 3 strains studied were of the opposite character and less marked. By the use of optimal concentrations of Al(+++) (12 mM for type 1 and 1 mM for type 2) attenuated strains can be separated from mixtures containing virulent type 1 or 2 strains. The A marker was found to be correlated with the d but not the rct/40 or T marker. The A marker has been used for following genetic changes of vaccine strains after their multiplication in man.

Aluminum↗
PubMed1962

Thermal inactivation of poliovirus under anaerobic conditions.

Wallis, Craig (Baylor University, Houston, Texas) and Joseph L. Melnick. Thermal inactivation of poliovirus under anaerobic conditions. J. Bacteriol. 84:389-392. 1962.-Of the six strains of poliovirus tested (three antigenic types), none was stabilized at 50 C under anaerobic conditions. The previously reported stabilization of polioviruses using thioglycolate had been attributed to anaerobic conditions. However, the sparing effect attained with high concentrations of thioglycolate was achieved as readily with other organic salts (benzoate, acetate) which could not be attributed to the anaerobic state. The viruses failed to be stabilized when low oxygen tension was obtained by dilute thioglycolate, l-cysteine, and nitrogen.

Acetates↗
PubMed1959

Studies on the pathogenesis of rabies in insectivorous bats. I. Role of brown adipose tissue.

Studies on the pathogenesis of rabies in two species of experimentally infected insectivorous Chiroptera, the Mexican free-tailed bat (Tadarida mexicana), a quasi hibernator, and the little brown bat (Myotis lucifugus), a deep hibernator, provided evidence that brown adipose tissue may serve as an extraneural site for storage and multiplication of rabies virus. Although the Mexican free-tailed bat proved to be relatively insusceptible to experimental rabies infection, virus was demonstrated in the brown fat of 22 per cent of those animals shown to be infected by viral assay in white Swiss mice. Rabies infection in this species was most evident 20 to 40 days after intramuscular inoculation of virus. Rabies virus was found to be widely distributed in the little brown myotis 9 to 26 days following inoculation and virus concentrations in some of the tissues approached the level of the stock mouse brain virus suspension used in inoculating these bats. The shorter incubation period and higher virus titers in the tissues assayed reflect the increased susceptibility of Myotis lucifugus as compared with the Mexican free-tailed bat. Virus was demonstrated in the brown fat of 30 per cent of the experimentally infected Myotis. In the experimentally infected Myotis lucifugus and in the Syrian hamster which is highly susceptible to rabies infection, rabies virus was isolated more frequently from the brown fat than from the salivary gland indicating that in a susceptible host brown adipose tissue may be as frequent a site of viral proliferation as salivary gland. Since rabies virus was found to persist for long periods of time in the brown fat of experimentally infected bats and was occasionally demonstrated in this tissue alone, it is suggested that brown adipose tissue provides a mechanism by which these animals may serve as reservoirs for this agent in nature. The possibility that similar mechanisms may be involved in the maintenance of other viral agents during interepidemic periods is discussed.

Adipose Tissue↗