Yaba virus-specific DNA in the host cell nucleus

DNA-DNA hybridization studies show that Yaba virus-specific DNA is present in the host cell nucleus late in the infection cycle. The nuclear DNA appears to exist as a complete genome, not convalently linked to host cell DNA, as demonstrated by sedimentation analyses. The DNA apperas to be synthesized in the nucleus, since its level of incorporation of label is ten times the background incorporation detectable in the cytoplasm. Extraction of the nuclei by treatment with SDS and EDTA after precipitation with 1 M NaCl separates most of cellular DNA from the Yaba virus-specific DNA.

Inhibition of simian virus 40 DNA synthesis in Yaba virus-preinfected cells

The effect of Yaba virus preinfection on DNA synthesis in SV40-infected Jinet cells was studied. Time-course synthesis studies were conducted using the incorporation of labeled thymidine. Yaba virus preinfection resulted in the inhibition of SV40 DNA synthesis when the elapsed time between Yaba virus and SV40 infections was three days. This inhibition was demonstrated by hybridization studies and sedimentation analysis. In addition, the usual stimulation of cellular DNA synthesis induced by SV40 infection was inhibited. This inhibition occurred at a time in Yaba virus infection when no cytoplasmic Yaba virus-specific DNA synthesis occurred.

Phenytoin inhibition: failure to inhibit periosteal responses to lathyrogen

beta-Aminopropionitrile (BAPN) administered to rats has caused exostosis formation at sites of muscle attachment and also caused delay in the healing of soft tissue wounds and of bone fractures. Since phenytoin sodium has an opposite effect on wound healing, bone fractures, and the tensile strength of connective tissues, an experiment was performed to determine whether or not BAPN could produce periosteal exostoses in the presence of phenytoin. Rats that were given both BAPN and phenytoin produced similar exostoses as rats that were given BAPN alone. This indicates that phenytoin does not prevent inhibition of lysyl oxidase by BAPN, does not promote increased tensile strength of connective tissues in the presence of BAPN, and does not facilitate the detoxification of BAPN. Further, no evidence for an increased cellular response with phenytoin was observed. The mechanism by which phenytoin promotes wound healing is still unknown.

Malpractice in the United Kingdom

The end of the last century saw the development in the United Kingdom of medical protection and defense societies. Their history, objects, growth, and scope are outlined. Reference is made to leading cases of medical malpractice and to the relevant statutes. The relationship between the protection societies and the National Health Service authorities is dealt with and a comparison made of the relative situations in the United States and United Kingdom. Finally, recent trends are examined and views expressed about possible future developments in this field which will be the subject of recommendations by a Royal Commission on Civil Liability and Compensation for Personal Injury which is now sitting.

Pregnancy following jejunoileal bypass. Effects on fetal outcome

Four cases of pregnancy following jejunoileal bypass surgery for obesity are presented, and 9 cases from the recent literature are reviewed. Pregnancy after bypass surgery often resulted in low-birthweight infants (46%) at term, and this was especially true when conception occurred within 2 years of the surgery. In light of these findings it may be advisable to postpone pregnancy until after the second postoperative year.

Effects of subchronic steroid therapy on vitamin E-deficient rats (38480)

Experiments were carried out to determine the effectiveness of steroid therapy in vitamin E-deficiency, as measured by autohemolysis of isolated RBC's body weight gain, serum creatine phosphokinase activity, and stabilization or labilization of isolated hepatic lysosomes. Results of such experiments would indicate whether triamcinolone acetonide could supplant vitamin E in vitamin E-deficiency states via its ability to stablize various membranes. Autohemolysis induced by vitamin E-deficiency could not be prevented by daily administration of triamcinolone. Daily dosages of 0.1 and 0.4 mg/kg (ip) triamcinolone given concomitantly with replacement vitamin E (at sufficient dosages to reverse the autohemolysis) resulted in an increased autohemolysis. No changes in lysosomal membrane fragility were noted when hepatic lysosomes were obtained from vitamin E-deficient rats with triamcinolone resulted in a greater attenuation of body-weight gain. Creatine phosphokinase levels were not augmented in vitamin E-deficient rats. Vitamin E-deficient rats supplemented with vitamin E and treated with triamcinolone, manifested an increase in creatine, phosphokinase. It was therefore concluded that although triamcinolone and vitamin E possess a common ability to stablize membranes and proteins, their mechanisms must be different since triamcinolone could not substitute for vitamin E in a deficiency state. Indeed, triamcinolone was found to be more toxic in the absence of vitamin E.