In vitro carcinogenesis of hepatocytes obtained from acetylaminofluorene-treated rat liver and promotion of their growth by phenobarbital

The hepatic cells of rats being fed acetylaminofluorene were transferred into culture at various times. Proliferative hepatocytic foci were obtained from animals treated with the carcinogen for more than 9 weeks. These hepatocytic foci became transplantable and capable of growth in soft agar after 4 to 12 months in culture. Phenobarbital markedly enhanced the growth of these hepatocytes in culture.

Mechanisms of inhibition by simultaneously administered phenobarbital of 3'-methyl-4-(dimethylamino)azobenzene-induced hepatocarcinogenesis in the rat

The mechanisms of inhibition by simultaneously administered phenobarbital of 3'-methyl-4-(dimethylamino)azobenzene (3'-Me-DAB)-induced hepatocarcinogenesis in the rat were studied. Weanling rats were fed a diet containing 0.06% 3'-Me-DAB or 0.06% 3'-Me-DAB and 0.05% phenobarbital for 3 weeks, followed by either basal diet or a diet containing 0.05% phenobarbital as a promoter. The number and the size of enzyme-altered islands and the number of tumors larger than 5 mm in diameter were scored at week 12 and week 40, respectively. The simultaneous feeding of phenobarbital and 3'-Me-DAB resulted in a significant decrease in the number and size of enzyme-altered islands and in the number of tumors, in comparison with those scored in animals fed 3'-Me-DAB alone. It was concluded that the simultaneous feeding of phenobarbital inhibits both the initiation of carcinogenesis and also the promotive action of the carcinogen resulting from its selective toxicity on the liver tissue.

Dissecting aneurysm during pregnancy and the puerperium

According to Schnitker, Mandel, Hirst and their associates, approximately half of the dissecting aneurysms in women under 40 years of age are associated with pregnancy. This significant relationship between dissecting aneurysm and pregnancy has been discussed by considering hemodynamic stress and also the hormonal changes of pregnancy. In this report, we describe five patients with dissecting aneurysm during pregnancy or the puerperium, review the literature and discuss the influence of pregnancy on the pathogenesis of this disease.

Induction of gamma-glutamyl transpeptidase activity by dietary phenobarbital in "spontaneous" hepatic tumors of C3H mice

Biochemical features of spontaneous hepatic tumors in C3H mice were studied histochemically in comparison with those of neoplastic lesions developed in animals fed dietary phenobarbital (PB) continuously or treated with diethylnitrosamine (DEN) during 11 approximately 14 weeks of age. All 42 spontaneous hepatic tumors that developed in control mice by 74 weeks of age were completely negative for gamma-glutamyl transpeptidase (gamma-GTPase) activity. Dietary phenobarbital enhanced hepatic tumorigenesis remarkably, and 32 out of 43 tumors found at 70 weeks showed multifocal gamma-GTPase activity. DEN induced gamma-GTPase-positive islands of hepatocytes, but 12 out of 13 tumors larger than 5 mm in diameter that developed by 60 weeks were gamma-GTPase-negative. The phenomenon of induction of gamma-GTPase activity by PB in "spontaneous" hepatic tumors appears to be important both for elucidating the mechanism of promotion by PB and also for analyzing multisteps of carcinogenesis.

Induction by parathyroid hormone of ornithine decarboxylase in rabbit costal chondrocytes in culture

The activity of ornithine decarboxylase (ODC) in rabbit costal chondrocytes in culture markedly increased after addition of parathyroid hormone (PTH), reaching a maximum 4 to 5 h after PTH addition. The effect of PTH was dose-dependent both in the presence and absence of fetal calf serum. Addition of cycloheximide or actinomycin D prevented the induction of ODC by PTH. Calcitonin, 1,25-dihydroxyvitamin D3, and vitamin A had no stimulatory effect on the activity of ODC, and did not inhibit the induction of ODC by PTH, when added with PTH.

[Postoperative spinal canal stenosis (author's transl)]

Four cases of postoperative spinal canal stenosis were presented in which compression of cauda equina was observed. The lesion was found in 5.8% of operated spinal stenosis (four out of 69 cases). One must pay attention to differentiate the lesion from the recurrence of initial disorder, because the symptoms of the postoperative spinal stenosis is no always typical but sometimes resemble to the symptoms of the initial disorder which needed the operation. Myelography is the only reliable method to decide the extent of the spinal canal stenosis.

[Effects of a proteolytic-enzyme preparation used concomitantly with an antibiotic in osteoarticular infections (author's transl)]

Studies were performed in 8 patients with osteoarticular infections to examine the concentrations of sulbenicillin in the venous blood and exudate following administration and the concentrations of the antibiotic in the exudate when serratiopeptidase was orally administered concomitantly with the antibiotic. The results of the examination indicated that the transfer of sulbenicillin into the exudate tended to increase when 30 mg/day of serratiopeptidase was concomitantly given for 6 days, though further examination was thought necessary by increasing number of subjects and elaborating on the methodology.

Preparation of perfluorodecalin emulsion, an approach to the red cells substitute

The major problems unsolved in fluorocarbon emulsions have been the long lasting retention of the substance in tissues of organs and acute shock symptom in animals receiving "coarse" emulsion with particles larger then 0.2 mum. This report offers a new, stable and sterile preparation of 25% "fine" perfluorodecalin emulsion with yolk phospholipid that is eliminated from liver, spleen and other organs within a few weeks, and whose acute and subacute toxicity is as low as perfluorotributylamine/Pluronic F68 emulsion. Effects of the perfluorodecalin emulsion thus prepared for maintaining contractile force of isolated guinea pig heart by perfusion and survival of animals receiving repeated circulatory exchange proved similar to perfluorotributylamine/Pluronic F68 emulsion.

Measurement of venous blood flow and pressure using thermoelectric and pressure transducers

In order to simplify procedures for testing the circulatory function of a patient, changes in the venous blood flow as well as venous pressure following exercise were continuously observed using the thermoelectric flowmeter. The level of zero flow necessary for evaluation of the velocity of flow was successfully indicated without occlusion of blood vessels by means of a form of compensation for thermal diffusion devised by the authors.