Inhibitory effect of retinoid on esophageal carcinogenesis in rats induced by N-nitroso-N-methylbutylamine in relation to cellular retinoic acid-binding protein.

The inhibitory effect of a synthetic retinoid, ethyl alltrans-9-(4-methoxy-2, 3, 6-trimethyl-phenyl)-3, 7-dimethyl-2, 4, 6, 8-nonatetraenoate (Tigason), on esophageal carcinogenesis in F344 rats induced by N-nitroso-N-methylbutylamine (NMBA) was evaluated. The animals were given NMBA daily in their drinking water for 21 weeks at a concentration of 15 mg per liter ad libitum starting at 8 weeks of age. One week before the beginning of NMBA treatment, the rats were divided randomly into Tigason-fed and -unfed groups. Thirty-five rats were fed a diet supplemented with Tigason at a concentration of 30 mg per kg of diet, and 80 rats were given a basal diet alone. In NMBA-treated rats, multiple papillomas were seen 11 weeks after NMBA treatment and squamous cell carcinoma developed 12 weeks after NMBA; the tumors increased in number thereafter, and the numbers of papillomas and carcinomas were the same at 17 and 21 weeks after NMBA. At 21 weeks after NMBA treatment, the number of papillomas was similar, regardless of the dietary Tigason supplement, however, the number of esophageal squamous cell carcinomas was significantly lower in the Tigason-fed rats than in -unfed animals (p < 0.025). In normal esophageal tissues, a small amount of cellular retinoic acid-binding protein (cRABP) was detected throughout the experimental period, while during carcinogenesis, the levels of cRABP increased continuously until 16 weeks after NMBA; the cRABP level was higher in papillomas than in squamous cell carcinomas. As Tigason specificially blocked the progression of papillomas to carcinomas, it may be a promising candidate chemopreventive agent in esophageal carcinogenesis.

Vaginal atresia with transverse septum in a cat.

A six and half-year-old nulliparous mixed breed cat which had the complaints of vomiting, abdominal distention and depression was presented to the Veterinary Teaching Hospital of Osaka Prefecture University. She was suspected of pyometra by clinical signs and tests. By laparotomy, it was clarified that both uterine horns and vagina showed distension by the accumulation of secretions, and the vagina ended blindly leaving a tough connective tissue at the border between cranial and caudal part of the vagina. Postoperative contrast-radiograph of the remaining vagina proved it had no persistence of the hymen. From these findings, the condition was diagnosed as a feline atresia vaginalis with the transverse vaginal septum which is caused by the embryonic failure of canalization of the paramesonephric duct between the end of the Müllerian duct and the urogenital sinus.

[Hepatic parenchymal changes after intraarterial administration of lipiodol: an animal experiment].

The effect of Lipiodol (LPD) on the hepatic parenchyma bearing VX2 tumor was investigated in 12 rabbits. In these rabbits Adriamycin (ADM) soluble Urografin and LPD were injected through the hepatic artery. As the control another 12 rabbits bearing VX2 tumor which were intraarterially injected with ADM solution in saline were used. Liver function tests revealed significantly higher values of serum transaminases in the LPD group than in the control group. Histologically in the LPD group, hepatocellular degeneration was observed and the severity was at its peak 3 days after injection whereas control animals preserved almost normal structure. The degeneration of the tumor-bearing lobe was more severe than that of the tumor-free lobe. This study showed the histologically and functionally demonstrable adverse effects of LPD.

A case of rheumatoid arthritis which developed after recovery from adult respiratory distress syndrome.

A 53-year-old previously healthy woman suddenly developed adult respiratory distress syndrome (ARDS) of unknown etiology. High-dose corticosteroid pulse therapy and artificial ventilation were started immediately and she dramatically responded to the treatment. However, soon after recovery from ARDS, she developed typical rheumatoid arthritis (RA). Although no apparent relationship between RA and ARDS was clear, this case is quite suggestive in the consideration of the etiology of ARDS.