To clarify the changes occurring in diabetic animals in the responsiveness of the myocardium to alpha 1- and beta-adrenoceptor agonists, we examined both alpha- and beta-adrenoceptor-mediated electrophysiological and mechanical responses in the depolarized right ventricular papillary muscle of streptozotocin (STZ) induced diabetic rats and age-matched controls. Both methoxamine (10(-7)-10(-4) M) and isoproterenol (10(-9)-10(-6) M) enhanced the slow response action potential in a concentration-department manner. The amplitude and the APD50 (time required for 50% repolarization) of the methoxamine-induced slow response action potential were both markedly increased in STZ-induced diabetic rats in comparison with control rats, whereas those of the isoproterenol-induced slow response were significantly decreased. The methoxamine-induced contraction in depolarized muscle was slightly but not significantly increased in STZ-induced diabetic rats, whereas the isoproterenol-induced contractile response was significantly attenuated. The maximum number of binding sites (Bmax) for [3H]dihydroalprenolol and for [3H]prazosin were both significantly decreased in diabetic rats, compared with age-matched control rats, without any change in the affinity constants. The slow response action potential induced by methoxamine but not isoproterenol was attenuated by IAP (islet-activating factor) treatment (50 micrograms/kg, i.v. for 3 days). These results suggest that an alpha-adrenoceptor-mediated electrophysiological response is unmasked when the beta-adrenoceptor-mediated response is desensitized in the papillary muscle of STZ-induced diabetic rats.

Objective To clarify the incidence of concomitant esophageal cancers in patients with head and neck cancer (HNC), and to investigate which risk factors are responsible for this association.Patients and Methods From 1994 to 2000, 134 patients with HNCunderwent upper gastrointestinal endoscopy using the 0.8% Lugol stain method to detect esophageal cancer. Acase-control study was designed to compare HNC patients with and without esophageal cancer. Logistic-regression analysis was used to obtain odds ratios of risk factors.Results Out of 134 patients with HNC, Lugol unstained area was detected in 42 patients. Biopsy specimens revealed squamous cell carcinoma in 17 (12.7%), dysplasia in 9 patients (6.6%), and normal in the others. Gastric carcinoma was also detected in 7 patients (5.2 %). The estimated depth of cancer invasion was mucosa in 9 patients, submucosa in 5 patients, and proper muscle or deeper in 3 patients. In the results of statistical analysis, high alcohol consumption of more than 75 g per day increased the risk of esophageal cancer (odds ratio: 20.2, p<0.01). Intake of hard liquor showed a high odds ratio (whisky: 28.7, p<0.05, shochu: 12.7, p<0.05). The amount of cigarette smoking was not related to this association. Conclusion High incidence of esophageal cancer was found in the patients with HNC. A high alcohol consumption level, and in particular hard liquor, participated in the development of esophageal cancer in the patients with HNC. But cigarette smoking was not related to this association. (Internal Medicine 40: 692-696, 2001)

The preventive effects of hydroxychalcone derivatives on ulcer formation induced by severe necrotizing agents such as 60% ethanol in 150 mM HCl (HCl-ethanol) and 0.2 N NaOH in rats were examined. Among the compounds tested, 2',4'-dihydroxychalcone gave the strongest activity in both experimental models and protected the gastric mucosa from the insult of either necrotizing agent at oral doses ranging from 1 to 10 mg/kg, as evidenced by a dose-related reduction in the ulcer index. The mucosal protective activity of 2',4'-dihydroxychalcone was not affected by pretreatment with indomethacin (5 mg/kg, s.c.). To investigate the detailed mechanism of the mucosal protective action of 2',4'-dihydroxychalcone, its inhibitory effects on the decrease in the hexosamine content from the gastric mucus induced by HCl-ethanol were studied by using it in combination with a dye, Alcian blue. As a result, 2',4'-dihydroxychalcone at an oral dose of 10 mg/kg inhibited the decrease in the dye-recovery from the gastric mucus induced by HCl-ethanol. PGE2 at an oral dose of 0.1 mg/kg exhibited a similar action. These results established that 2',4'-dihydroxychalcone is a potent cytoprotective agent similar to PGE2 effectively preventing gastric ulcer formation induced by strong necrotizing agents and seems to suggest that this compound protects the stomach against its own peptic secretions by reinforcement of gastric resistances. In fact, 2',4'-dihydroxychalcone prevented ulcer formation induced by water-immersion stress in rats and also showed a marked enhancement of the healing of acetic acid-induced gastric ulcers in rats.

Leiomyomatosis peritonealis disseminata (LPD) is a rare benign smooth muscle tumour located in the peritoneal cavity. Increased oestrogen exposure appears to be an aetiological factor for LPD. We report two cases of LPD after leiomyomectomy and assisted reproductive technology pregnancy, which can cause a high serum concentration of oestrogen. CT and MR scanning demonstrate many intraperitoneal well-demarcated nodules of varying size that mimic widespread intraperitoneal malignancy.

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