In a survey of 49 papilloma patients accurate maternal condyloma history was obtained in 31 instances and of these, 21 were positive for the presence of condyloma during pregnancy or parturition. Molecular virological studies indicate that positive hybridization could be demonstrated to human papilloma virus 2 in both laryngeal papilloma and condyloma by the Southern blot technique. Immunoperoxidase staining illustrated the presence of virus-related particles only near the surface of the mucous membrane papilloma, which is in contrast to the definite staining of the stratum granulosum and stratum corneum of verrucae. Collectively this provides convincing evidence for an etiological relationship between condyloma acuminata and some laryngeal papillomata. The highly contagious nature of human papilloma virus infection is discussed and the possibility of cesarian section in the presence of active condyloma must be considered.

No abstract

No abstract

No abstract

The level of messenger ribonucleic acid specific for the argECBH gene cluster (arg-mRNA) of Escherichia coli was measured by deoxyribonucleic acidribonucleic acid hybridization in a number of strains. During the first 10 min after removal of arginine (derepression), the rate of arg-mRNA accumulation was six to ten times greater than that found in arginine-repressed argR+ cells. In the absence of arginine, L-canavanine (200 gg/ml) repressed arg-mRNA synthesis to a level only 20 to 30% lower than that found after arginine deprivation. High levels of arg-mRNA were produced by argRstrains with or without added arginine. Within about 2 min after arginine addition to argR+ cells, the rate of synthesis of arg-mRNA reached the repressed level. Likewise, 2.5 min after rifampin addition, all transcription of arg-mRNA was completed. These data are consistent with the view that arginine signals repression by inhibiting the initiation of transcription of arg-mRNA mediated in some way by the argR gene. The kinetics of arg-mRNA accumulation and the kinetics of completion of transcription together with the profile of hybridizable arg-mRNA in sucrose density gradients (major component 16S) suggest that the argECBH gene cluster is transcribed in short pieces rather than as a single unit.