Biomedical subjects

R R Fox

Publications and source records attributed to R R Fox.

At least 55 records · Page 3Linked to original sources

PubMed1976

Presence of a high-molecular-weight RNA and RNA-directed DNA polymerase in rabbit hereditary lymphosarcoma.

Rabbit lymphosarcoma tissues contain 70 S RNA and RNA-directed DNA polymerase encapsulated in particulate components that band in the density region of type C RNA viruses. RNA-directed DNA polymerase associated with the particles could be distinguished from cellular DNA polymerases by salt elution from phosphocellulose. The enzyme preferred the template primers poly(rA)-(dT)12-18 and poly(rC)-(dG)12-18 over other synthetic template primers and also utilized viral 70 S RNA as template; these properties are not observed with the known cellular DNA polymerases.

Animals↗

PubMed1975

Transplacental induction of primary renal tumors in rabbits treated with 1-ethyl-1-nitrosourea.

Pregnant rabbits of the two partially inbred strains III and WH were given ip injections of a single dose of 1-ethyl-1-nitrosourea (ENU) (60 mg/kg) in trioctanoin on day 18 of gestation. Controls were treated on the same day with solvent alone. Fourteen of 15 strain III progeny that survived more than 8 weeks developed primary renal tumors at a mean age of 3.3 months. Five other treated strain III progeny died at an early age due to other causes. In contrast, only 3 of 7 strain WH offspring surviving more than 8 weeks developed renal tumors; they had about the same latency period (3.9 months). In each strain, either renal tubular cystadenomas or mixed nephroblastomas appeared to develop within small renal cortical cysts. In strain III, the presence of these cysts may have been due to a high frequency of a recessive gene (rc) for renal cysts, but in strain WH they were induced by ENU. The differential strain incidence suggests that susceptibility to renal tumor inducibility by ENU is increased by the presence of the rc/rc genotype for cyst formation.

Animals↗

PubMed1975

Strain differences in aryl hydrocarbon hydroxylase induction by 3-methylcholanthrene in rabbits.

We determined both basal and induced AHH activity in livers of six partially inbred strains of rabbits. Strain III rabbits had the highest enzyme activity upon induction by 3-MCA, i.e., four to five times that in strain WH (noninducible), which has the lowest enzyme activity. AHH induction was also "low" in strains X, OS, ACEP, and AC. F1 hybrids between strains III and WH revealed a differential response to the induction of liver AHH activity by MCA: the levels of induced hydroxylase activity were consistently higher in (III X WH)F1 rabbits than in the reciprocal (WH X III)F1 hybrids. All possible crosses between these two "extreme" strains are now being analyzed to estimate the number of genes involved in their response difference to MCA.

Animals↗

PubMed1974