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Biomedical subjects

C C Randall

Publications and source records attributed to C C Randall.

49 records · Page 3Linked to original sources
PubMed1970

Morphology and entry of enveloped and deenveloped equine abortion (herpes) virus.

Selective removal of the envelope of equine abortion (herpes) virus was accomplished by utilizing the nonionic detergent Nonidet P-40 followed by sonic treatment. The deenveloped particles differ significantly in size and buoyant density from the enveloped form. The cellular entry of purified enveloped and purified deenveloped virus was examined by electron microscopy during critical time periods. Both forms appeared to enter cells by a viropexis mechanism in which particles were engulfed by pseudopodia which either surround the virus and fuse with the cell membrane or to other pseudopodia, forming fusion vacuoles containing from one to numerous viral particles. This mode of entry was noted extensively at 5 min postinoculation. Deenveloped particles were apparently infectious only for hamsters, with a large inoculum being required. Contamination by enveloped forms was not noted after exhaustive search by electron microscopy.

Animals↗
PubMed1968

Biosynthesis of host and viral deoxyribonucleic acid during hyperplastic fowlpox infection in vivo.

The synthesis of deoxyribonucleic acid (DNA) during in vivo infection of chick epithelium with fowlpox virus was examined by incorporation of tritiated thymidine into the acid-insoluble fraction. The proportion of precursor incorporated into host and viral DNA at various times after infection was determined by chromatography on columns of methylated albumin-kieselguhr. The first 60-hr period of infection was characterized by the synthesis of predominantly host DNA, the rate of production of which increased markedly over the control between 36 and 48 hr postinoculation (PI). Although the replication of viral DNA began between 12 and 24 hr PI, the rate of synthesis was very low during the first 60 hr. In contrast, an abrupt increase in the rate of viral DNA synthesis occurred between 60 and 72 hr PI, concomitantly with a sharp decline of host DNA synthesis. Subsequently, between 72 and 96 hr, the ratio of synthesis of viral DNA to host DNA progressively increased to a maximum of greater than 2:1. The temporal relationship of this biphasic pattern of host and viral DNA synthesis to hyperplasia and viral replication is discussed.

Albumins↗
PubMed1968

Kinetics of viral deoxyribonucleic acid, protein, and infectious particle production and alterations in host macromolecular syntheses in equine abortion (herpes) virus-infected cells.

Infection of exponential-phase suspension cultures of mouse fibroblast cells (L-M) with equine abortion virus (EAV) resulted in inhibition of cell growth and marked alterations in host metabolic processes. The synthesis of deoxyribonucleic acid (DNA) and ribonucleic acid was inhibited within 4 hr after infection and was suppressed by more than 90% by the time of maximal virus replication (14 to 18 hr). The overall rate of protein synthesis, however, was similar in uninfected and virus-producing cells as determined by measurements of net protein and isotope incorporation. The time course of viral DNA and protein synthesis and assembly into mature virus was determined with the inhibitors 5-fluorodeoxyuridine (FUdR) and cycloheximide, respectively. Thus, viral DNA synthesis was essentially completed at 14 hr, and viral protein and infectious virus synthesis was completed at 18 hr. Although the number of plaque-forming units (PFU) produced by FUdR-treated cells (10(3) to 10(4) PFU/ml) was at least 3 logs less than that produced by untreated cells, the yield of physical particles (as determined by electron microscopy) was approximately the same at 30 hr after infection. Besides being relatively non-infective, the particles produced in FUdR-treated cells appeared morphologically incomplete as they contained little or no nucleoid material.

Abortion, Veterinary↗
PubMed1966

Physicochemical properties of fowlpox virus deoxyribonucleic acid and its anomalous infectious behavior.

Randall, Charles C. (University of Mississippi, Jackson), Lanelle G. Gafford, Richard L. Soehner, and James M. Hyde. Physicochemical properties of fowlpox virus deoxyribonucleic acid and its anomalous infectious behavior. J. Bacteriol. 91:95-100. 1966.-Deoxyribonucleic acid (DNA) was extracted from fowlpox virus-infected tissue, purified inclusions, and purified virus by five variations of detergent and phenol methods. Phenol methods gave a poor yield, whereas detergent techniques extracted up to 78% of the DNA. The buoyant density was 1.695 g/ml, and the melting temperature in 7.2 m NaClO(4) was 39 C, both approximately equivalent to a guanine plus cytosine content of 35 moles per cent. Further proof of the double-stranded nature of the DNA was shown by the characteristic behavior toward deoxyribonuclease, formaldehyde, and heat. Infectious DNA was obtained by the various methods described, but this manifestation of biological activity was capricious and for unknown reasons was often not evident. The infectivity could not be related quantitatively to the amount of DNA employed. Furthermore, the infectious nature of fowlpox virus DNA was demonstrable only when the route of infection was the chorioallantoic membrane. In contrast, whole virus infected both membrane and chick skin with equal efficiency.

Biological Assay↗
PubMed1965

Lability of host-cell DNA in growing cell cultures due to Mycoplasma.

In HeLa-cell cultures chronically infected with Mycoplasma, (PPLO) host-cell DNA is unstable as detected by incorporation of H(3)-or C1 i-thymidine into DNA and subsequent release into the medium as acidsoluble radioactivity. This characteristic can be transmitted to PPLO-free cultures of strain L cells by inoculation with preparations of PPLO from the HeLa cells, although chronically infected cultures of L cells continue to multiply. In addition, virus preparations also may carry PPLO contamination through numerous passages.

Carbon Isotopes↗