Similarities and differences in the regulation of hepatic cytochrome P-450 enzymes by diabetes and fasting in male rats

The effects of streptozotocin-induced diabetes and fasting on hepatic cytochrome P-450 enzymes in sexually mature male rats were studied by immunochemical techniques and enzyme assays. The level of cytochrome P-450ac (an acetone/ethanol inducible form), 65 pmol/mg microsomal protein in control rats, increased 4- to 5-fold in diabetic rats and 3- and 5-fold in fasting rats. In contrast, P-450 UT-A (a male specific form) decreased drastically from 295 pmol/mg in the control group to about 10% of this value in diabetic rats and to 50% in fasting rats. P-450 PCN-E (a 16 alpha-cyanopregnenolone/dexamethasone inducible form), on the other hand, decreased from 151 pmol/mg to 38% in diabetic rats and increased 2-fold in fasting rats. These changes were also reflected in catalytic activities using N-nitrosodimethylamine, benzphetamine, and erythromycin as substrates. Slight changes in cytochromes P-450 UT-F, P-450 UT-I and P-450 PB-C were also observed under these conditions, but the biological significance is not known. These results suggest that different mechanisms exist for the regulation of the expression of cytochrome P-450 enzymes in diabetic and fasting rats.

[One stage resection of esophageal cancer and pulmonary bulla--a report of three patients]

Since 1982, three patients with esophageal cancer complicated with pulmonary bullae have been treated by operation on the esophagus and lung in one performance: In all the patients, the bullae were on the same side of the operation. The esophageal or cardiac cancer was resected first, then the bulla was treated. The site of esophago-gastric anastomosis was reinforced by the greater omentum. For mid-upper esophageal cancer, cervical anastomosis was done in order to avoid infection or leakage. In the third patient, pyopneumothorax occurred after wedge resection of a large bulla in the right upper lung and the surrounding tissues. The patient survived after timely drainage and medical management. The extent of resection for pulmonary bulla (bulla, segment or lobe) depends on the location, shape, size and number of the bullae and the pathological change in the surrounding tissues. We suggest that the indications: Cardio-pulmonary functions of the patient be stage II or better, even with mild emphysema so as they can tolerate anesthesia and surgery. Pulmonary function can be compensated after the lesion is removed, otherwise it is taken as a contraindication. The one stage removal of two foci makes it possible to avoid postoperative complications.