We have studied the effect of butyrate on mammary tumorigenesis by 7,12-dimethylbenz(a)anthracene. As reported previously, a high incidence of mammary tumors was observed in rats fed a basal diet containing 20% margarine. However, the enhancing effect of margarine was inhibited when sodium butyrate was supplemented in the high margarine diet. Sodium butyrate did not cause any effect when it was supplemented in the basal diet. The result suggests a possibility that a part of the inhibitory effect of butter on mammary tumorigenesis, which we had previously reported, was caused by butyrate milk lipids.

9,10-Dimethyl-1,2-benzanthracene↗

PubMedDate not supplied

Aspirin shares a short-term effect, inhibition of pyruvate kinase activity with tumor-promoting agents, but fails to promote rat liver carcinogenesis.

Since aspirin was found to cause a persistent decrease in pyruvate kinase activity, which is a prominent characteristic of the hepatic promoters, the effect of aspirin on hepatic tumorigenesis in the rat has been studied. Male Wistar rats were initiated with a diet containing 0.06% 3'-methyl-4-dimethylamino-azobenzene for 4 weeks. They were divided into 3 groups and each group was fed one of the following diets containing either 0, 0.5 or 1% aspirin. At the end of a 58-week experimental period, no differences were observed in the incidence of hepatic lesions and hepatocellular carcinomas among the groups. Thus, it was concluded that aspirin does not promote nor inhibit the postinitiation step of hepatic tumorigenesis in the rat.

Animals↗

PubMedDate not supplied

Adhesion preventive effect of a novel hyaluronic acid gel film in rats.

This study evaluated the efficacy of a novel hyaluronic acid (HA) gel for preventing adhesions in a rat caecal model. The gel was manufactured from an acidic HA solution using a freezing procedure. HA gel films with four different half-lives (50-200 h) in physiological buffered saline at 37 degrees C were prepared, by regulating the freezing time, and tested. The HA gel film was applied as a barrier on the injured caecal surface after standardized treatment with a rotary abrasion apparatus. A control group of 20 animals were abraded in the same way but not treated. Seven days after the initial operation, the incidence and severity of any adhesions were recorded. Application of the HA gel film significantly reduced the incidence and severity of adhesion formation in all treatment groups compared with the control group. This novel HA gel film is effective for reducing post-operative adhesions in this rat model and the resorption rate is optimum for adhesion prevention on the caecal surface.

Animals↗

PubMedDate not supplied

Tumor size does not have prognostic significance in stage Ia NSCLC.

PURPOSE: We aimed to determine whether the prognosis of non-small cell lung cancer (NSCLC), with lesions 2 cm or less in diameter, was better than that of Stage Ia lung cancer having a diameter of more than 2 cm. METHODS: We reviewed 64 cases of NSCLC which were preoperatively diagnosed as TINOMO. The tumors were classified into 2 groups on the basis of a tumor diameter set at 2 cm. After comparison of background factors, we compared the prognoses of the groups and determined the prognostic factors in Stage IA NSCLC. RESULTS: No differences were observed in the survival rate between the 2 groups. Statistically significant factors for the survival period in Stage IA NSCLC were serum carcino-embryonic antigen (CEA), residual tumor condition and lymph node metastasis. Those cases where CEA was abnormal were all in Stage II or inllmore advanced stage. CONCLUSION: It is not justifiable to sub-classify Stage IA NSCLC on the basis of a tumor diameter of 2 cm. The present study revealed that the most important preoperative prognostic factor was serum CEA.

Adenocarcinoma↗