Improvement of human faecal flora-associated mouse model for evaluation of the functional foods.

AIMS: Animal models are required for evaluation of the functional foods such as pro/prebiotics exerting effects through the metabolism of the intestinal microflora. The object of this study was to establish new human flora-associated mice reflecting the environment of the human intestinal tract. METHODS AND RESULTS: We inoculated a human faecal suspension into segmented filamentous bacteria (SFB) monoassociated mice as a model system. In both human flora (HF) and SFB-associated mouse (HF-SFB mouse), intestinal characteristics such as the composition of intraepithelial lymphocytes, the expression of major histocompatibility complex (MHC) class II molecules and the number of immunoglobulin A-producing cells in the mucosa was closer to those of conventionally reared mice than was case with human flora-associated mice (HF mice) lacking SFB. Several predominant bacterial groups except lactobacilli in human flora were found in faeces of HF-SFB mice. Lactobacilli established small populations in the gut of HF-SFB mice when administered before inoculation with the human flora. Faecal enzymatic activities and organic acid concentration of HF-SFB mice proportionally reflected those of the donor subject. CONCLUSION: We established a new human flora-associated mouse (HF-SFB mouse), in which intestinal characteristics are normally developed and their major microbial composition reflect the human. SIGNIFICANCE AND IMPACT OF THE STUDY: HF-SFB mice are a valuable model for studying pro/prebiotic effects on the human intestine.

Inhibitory effect of microfibril wheat bran on azoxymethane-induced colon carcinogenesis in CF1 mice.

Microfibril wheat bran (MFW), a processed dietary fiber prepared by milling of coarse wheat bran (WB), is softer and has a more pleasant taste than WB. In this study, we examined the inhibitory effect of MFW on azoxymethane (AOM)-induced colon carcinogenesis in female CF1 mice and compared its effect with that of WB and cellulose (CL). The mice were fed a modified AIN 76 A diet supplemented with either MFW, WB, or CL at a final concentration of 20% (w/w). Six weekly s.c. injections of AOM (10 mg/kg body weight) were administered per mouse commencing 1 week after the start of the feeding period. Control mice were injected with saline only. Thirty-three weeks after the initial injection, the mice were sacrificed, examined for tumors, and the cecal contents were analyzed to determine the moisture content and the concentrations of short-chain fatty acids (SCFA). The average number of total tumors per mouse in the MFW (2.9 +/- 0.6, P = 0.017) and WB (5.3 +/- 1.3, P = 0.373) diet groups was lower than that of the CL diet group (7.5 +/- 1.3), though there was no significant difference in tumor incidence (94.7%, 90.0% and 94.7%, respectively) between the groups. More than 90% of the tumors in each group were adenocarcinomas. The incidence of adenoma and that of carcinoma in situ in the MFW diet group (5.3% and 0%, respectively) were also lower than those in the CL diet group (26.3 and 26.3%, respectively; P = 0.180 and P = 0.046, respectively). Analysis of the cecal contents revealed a significantly higher moisture content and significantly higher concentrations of SCFA, butyrate in particular, in the MFW and WB diet groups. The results of this study indicate that the source and texture of dietary fiber can influence tumor development in CF1 mice, and more specifically that MFW is a promising and useful dietary supplement with properties serving to protect against the development of colon cancer.

Molecular cloning of Frizzled-10, a novel member of the Frizzled gene family.

The Frizzled genes encode WNT receptors. Frizzled-10 (FZD10), a novel member of the Frizzled gene family, has been cloned and characterized. Nucleotide sequence analysis showed that human FZD10 gene encodes a seven-transmembrane-receptor of 581 amino acids, with the N-terminal cysteine-rich domain and the C-terminal Ser/Thr-Xxx-Val motif. Larger amounts of FZD10 mRNA, 4.0 kb in size, were detected in the placenta and fetal kidney, followed by fetal lung and brain. In adult brain, FZD10 mRNA was abundant in the cerebellum. Among cancer cell lines, FZD10 was highly expressed in a cervical cancer cell line, HeLa S3, and moderately in a colon cancer cell line, SW480. The FZD10 gene was mapped to human chromosome 12q24.33. FZD10 shares 65.7% amino-acid identity with Frizzled-9 (FZD9). FZD10 and FZD9 constitute a subfamily among the Frizzled genes.

[Prognosis of intra-arterial chemo-embolization in metastatic liver cancer].

We treated 63 patients (pts) suffering from metastatic liver cancer with intra-arterial infusion chemotherapy, and analysed 44 of their for survival since the first treatment with regard to the primary foci of cancer and the method of intra-arterial therapy. Via the superficial femoral artery, we performed superselective hepatic catheterization by Seldinger's method. Three types of intraarterial therapy were used: Gelfoam embolization with mitomycin-C (MMC) in 12 pts (GS-TAE), capillary chemo-embolization with MMC-Lipiodol emulsion in 28 pts (LP-TAI) and "one-shot" slow infusion of MMC or cisplatinum in 4 pts. Fifty-percent survival was 189 days in pts with metastases from colo-rectal cancer (n = 20), 109 days from gastric cancer (n = 9), 100 days from pancreatobiliary cancer (n = 5) and 240 days from breast cancer (n = 7). More than one-year survival was obtained in 13 out of the 40 pts (32.5%). Survival of 12 pts, treated with GS-TAE regimen, was not significantly superior to that of 28 pts with LP-TAI regimen. Hence, we conclude that LP-TAI is the treatment of choice in chemo-embolization for unresectable liver metastases, because it causes less damage to the hepatic arterial beds, and facilitates repeat intraarterial therapy in these pts.

[Preoperative chemoembolization of iopamiron-solved adriamycin and lipiodol on hepatocellular carcinoma--clinicopathological study of ten surgical cases].

Preoperative chemoembolization was performed in 10 patients with hepatocellular carcinoma. The therapeutic regimen included Adriamycin (ADM) solved in nonionic contrast media, Iopamiron and Lipiodol (LP). Two to four ml of the solution, containing 20-40 mg of ADM, was mixed with 5-10 ml of LP by "pumping" method. This emulsion was infused superselectively into the hepatic artery by the balloon-occluded method. The regimen contained no permanent embolic material (e.g., Gelfoam or Ivaron). Dense deposition of LP in the tumor was seen on the CT scan 3-4 weeks after TAI. Surgical specimens, resected 3-12 weeks after TAI, revealed total necrosis of the tumor in 4 cases, subtotal necrosis (more than 80% on the cut surface) in 3 cases, and partial necrosis (less than 80%) in 3 cases. Tumor invasion in the fibrous capsules was necrosed in 4/7 of the cases. Tumor thrombi in the portal vein were also necrosed in 2/4. Our new method is more effective than the previous ones of LP and ADM without Iopamiron, and is equally effective as the regimen using LP, anticancer drugs, and permanent embolic materials.

[The effect of PSK on laryngeal cancer].

In order to examine effects of PSK (polysaccharide Kureha) on laryngeal cancer, clinical results of 28 patients treated by PSK were compared with those of 31 of the historical control group. Three months after treatments, the PSK group showed a higher cumulative survival rate and better results in immunological parameters such as counts of peripheral lymphocyte, PPD and PHA skin reaction. However, these differences between the PSK group and the control group were not significant statistically, except peripheral leucocyte counts. The side effect was found in one patient who complained of stomach discomfort after applicating PSK.

Circadian rhythm of brain susceptibility to haloperidol during chronic administration.

Circadian fluctuation has been reported to exist to the effects of haloperidol after acute administration. In an attempt to clarify the viability of chronotherapy with haloperidol, the antiapomorphine effect of haloperidol after chronic administration was investigated in the present paper. Haloperidol was administered once daily at the same time for 21 consecutive days to rats which were kept under 12 hr lighting conditions with light onset at 19:30. Then the chronology of the antiapomorphine effect was investigated. The antiapomorphine effect was significantly stronger in the group treated at 19:30 than that treated at 13:30. These data agreed with the results found after the acute administration of the drug. After chronic administration, no difference was found in the plasma and brain level of haloperidol due to the time of administration. These experimental results seem to suggest that a circadian rhythm in the brain susceptibility to haloperidol exists even during chronic administration.