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J E KEMPF

Publications and source records attributed to J E KEMPF.

17 recordsLinked to original sources

PRESERVATION OF T2 BACTERIOPHAGE WITH LIQUID NITROGEN.

There have been few reports on the preservation of viruses at the temperature of liquid nitrogen (-196 C). In this study, factors affecting the survival of phage were observed. Phage lysates in broth did not lose titer after a storage period of 4 weeks in liquid nitrogen. The rate of freezing was not critical, but freezing in nitrogen vapor was not satisfactory. When the virus was partially purified and suspended in buffered saline solution, it rapidly lost titer. Of seven protective agents recommended in the literature, only gum acacia seemed to demonstrate significant protection of purified virus against loss of viability. The temperature of thawing of phage suspended in broth did not affect its titer after freezing and storing in liquid nitrogen.

Bacteriological Techniques↗

DECREASE OF BOUND SIALIC ACID AND INHIBITOR IN CHORIOALLANTOIC MEMBRANES INFECTED WITH INFLUENZA VIRUS.

Tess, Bernard R. (University of Illinois at the Medical Center, Chicago) and J. Emerson Kempf. Decrease of bound sialic acid and inhibitor in chorioallantoic membranes infected with influenza virus. J. Bacteriol. 86:239-245. 1963.-During the adsorption period after the inoculation of chick embryos with the PR8 strain of influenza A virus, bound sialic acid (BSiA) in the chorioallantoic membranes decreased, presumably as a result of cleavage of surface glycoprotein by the viral neuraminidase. A further decrease occurred between 1 and 6 hr after infection, indicating that cleavage of the surface glycoprotein was continuing, and that the enzyme may have begun to act upon intracellular glycoprotein. Decreased levels of BSiA continued until 48 hr after infection, possibly as a result of continued intracellular enzyme activity plus destruction of glycoprotein as virus was released from the surface of the cells. BSiA began to increase 48 hr after infection, presumably because of regeneration of glycoprotein and its decreased destruction by the viral enzyme, since the process of infection was largely completed. Heat-stable hemagglutination inhibitor did not begin to decrease until 8 hr after infection; thereafter, the levels of BSiA and inhibitor appeared to be related.

Adsorption↗