Work in progress: radioprotection of human breast cancer cells by elevation of intracellular cyclic AMP

MCF-7 human breast cancer cells that were treated for one hour prior to X irradiation with the cyclic AMP-inducing agent 1-methyl-3-isobutylxanthine displayed a slight but significant increase in surviving fraction over untreated controls at each radiation dose level. This was accompanied by a two-fold increase in the level of intracellular cyclic AMP.     

Study on toxicity of butylated hydroxyanisole (BHA) in pregnant gilts and their foetuses

An embryotoxicity study on butylated hydroxyanisole (BHA) was carried out in SPF pigs (Danish Landrace). BHA was incorporated in the diet and administered to pigs in doses of 0, 50, 200 and 400 mg/kg body wt/day from mating (artificial insemination) to day 110 of the gestation period, when the foetuses were removed. Significant lower weight gain was observed in the dams dosed 400 mg/kg body wt/day. Absolute and relative organ weight for the liver and thyroid gland showed a dose-related increase. BHA neither affected the reproduction data nor the incidence of defects in the foetuses.     

Urothelial atypia and survival rate of 500 unselected patients with primary transitional-cell tumour of the urinary bladder

In a consecutive series of 500 unselected patients with primary urinary bladder tumours the influence of urothelial atypia on the 5 years survival-rate was examined. All tumours were transitional-cell tumours categorized according to the T-classification. Mucosal biopsies from 7 pre-selected sites were taken at the initial cystoscopy in 391 patients (78%) to identify urothelial atypia. The over-all cumulative 5 years survival-rate was 48%. Submucosal and muscle invasion had major influence on survival, whereas tumour grade was less important. Patients with urothelial atypia fared significantly worse than those with normal bladder mucosa (5 years survival 42% versus 62%). This difference in survival-rate became apparent first after two years of observation. Grade II atypia in the bladder mucosa and grade III (carcinoma in situ) had equal significance assessed by the survival-rates.     

Comparison of systemic and local immunity in dogs with canine parvovirus gastroenteritis.

To determine whether resistance to canine parvovirus (CPV) gastroenteritis is mediated by local or systemic immunity or both, an enzyme-linked immunospecific antibody assay (ELISA) was developed that quantitated different classes of antibody to CPV. Antibody levels in serum and feces of dogs with CPV-associated gastroenteritis were compared with their clinical signs and viral hemagglutination (HA) titers. Dogs with high levels of CPV coproantibody had a favorable clinical prognosis, high serum antibody levels (hemagglutination inhibition [HI] and ELISA), and low viral HA titers in feces. Conversely, dogs with little or no detectable CPV coproantibody had severe clinical signs and associated mortality rates and high viral HA titers in feces. Many of these dogs had high HI antibody titers. Statistical analysis revealed that only coproantibody level correlated (inversely) with HA titer; serum antibody, whether measured by HI or ELISA, did not. These data suggest that local intestinal immunity is more important than humoral immunity in developing immunological resistance to CPV gastroenteritis.     

Observations of the early diuretic response after intravenous administration of bumetanide and furosemide in dogs.

A transient natriuretic peak was observed in dogs the third minute after the i.v. administration of the highly active diuretics bumetanide and furosemide. The peak is dependent on the sodium balance such that it is potentiated during positive sodium balance and is not observed in sodium depleted dogs. A relationship exists between the simultaneous occurrence of the peak and abolition of the cortico-medullary electrolyte gradient.     

Clonidine-induced increase of renal prostaglandin activity and water diuresis in conscious dogs.

I.v. administration of clonidine to conscious dogs induces a water diuresis with hyposmotic urine and minor effect on electrolyte excretion. The diuresis is preceded by an increased urinary PGE excretion, but no change of urinary ADH output is observed. Plasma renin activity decreases. Both ADH infusion and indomethacin pretreatment inhibit the diuretic effect of clonidine. The results support the hypothesis that clonidine-induced water diuresis is mediated via an anti ADH effect due to increased renal prostaglandin activity. Moreover the results suggest that there is no direct stimulation of renin release by PGE.     

The Effect of Arvin on Experimental Pulmonary Embolism in the Rabbit

S ummary . Arvin therapy produced alterations in the histological structure of experimental pulmonary emboli in rabbits. Early and extensive necrosis was observed in the emboli which were not organized by fibroblasts. The emboli disappeared more rapidly from the pulmonary vessels than in non-treated animals.