Fruit and vegetable consumption and risk of colorectal cancer in Japan: The Miyagi Cohort Study

OBJECTIVE: Adequate fruit and vegetable intake has been suggested to protect against colorectal cancer. However, several recent prospective studies have reported no association. We therefore examined the association between fruit and vegetable intakes and the risk of colorectal cancer in a prospective cohort study in Japan. DESIGN: Between June and August 1990, 47 605 Japanese men and women completed a self-administered questionnaire, including a food-frequency questionnaire. We divided the subjects into quartiles based on their self-reported fruit and vegetable consumption. There were 165 colon cancer and 110 rectal cancer incidences identified during 7 years of follow-up, to the end of December 1997. We used Cox proportional hazards models to estimate the relative risk (RR) of developing colorectal cancer according to the level of fruit and vegetable consumption, applying adjustments for potential confounders. RESULTS: No statistically significant association was observed between fruit and vegetable consumption and the risk of colorectal cancer. The multivariate RR of colon cancer in the highest quartile of fruit and vegetable intake compared with the lowest was 1.13 (95% confidence interval (CI) 0.73-1.75), the RR for vegetables alone was 1.24 (95% CI 0.79-1.95) and that for fruit alone was 1.45 (95% CI 0.85-2.47). The corresponding multivariate RRs for rectal cancer were 1.12 (95% CI 0.67-1.89), 1.14 (95% CI 0.67-1.93) and 1.41 (95% CI 0.73-2.73). CONCLUSIONS: We found no association between the consumption of fruit and vegetables and the risk of colorectal cancer among the Japanese population.     

Formation process of staining-type hypermelanosis in Japanese flounder juveniles revealed by examination of chromatophores and scales

Staining-type hypermelanosis, defined as blind-side melanosis occurring after completion of metamorphosis, reduces commercial value in hatchery-produced flatfishes. Detailed characterization was performed on the stained area of juvenile Japanese flounder Paralichthys olivaceus to physiologically understand this phenomenon. From 80 to 120 days after hatching, juveniles were reared in sandy and sandless tanks. By classifying the staining degree into 7 levels, about 2 times higher occurrence of middle-level staining was reconfirmed in sandless tank (about 80 %) than in sandy tank (about 40 %). In the stained area, we found 3 types of chromatophores (melanophore, xanthophore, and iridophore) and ctenoid scales, which would be typically observed on the normal ocular side. Detailed examination on the melanophores revealed further similarity between the stained area and the normal ocular side, in terms of the distribution at 2 layers (shallower and deeper than scale), and the densities in both layers (about 1000 cells/mm² above scale and 200 cells/mm² beneath scale). These results strongly suggest that the staining is a status change in the body surface conditions from the blind side to that on the ocular side, and not a simple darkening caused by disordered proliferation of melanophores on the blind side.     

Development of a sandwich enzyme-linked immunosorbent assay (ELISA) to quantify γ-glutamyl-carboxylated clotting factor IX and assess redox susceptibility of anticoagulant chemicals

Anticoagulant chemicals (ACCs) such as warfarin are widely used in medical applications as well as for their rodenticide properties. Their efficacy is greatly influenced by polymorphisms in the gene encoding vitamin K epoxide reductase (VKOR). Evaluation of the activity of ACCs toward VKOR variants is essential to determine their proper use. Presently, this is achieved by co-expressing VKOR of Rattus Norvegicus and human clotting factor IX in cultured cells and measuring inhibition of vitamin K-dependent gamma-glutamyl carboxylation of factor IX (glaFIX) activity. However, glaFIX has only been quantified using indirect methods like blood coagulation assays. We have developed a sandwich enzyme-linked immunosorbent assay using a glaFIX-specific antibody to quantify glaFIX and used this to analyze inhibition of VKOR activity by warfarin.     

Cloning and characterization of cDNA encoding a prohibitin-like protein from Theileria orientalis

A cDNA clone encoding a prohibitin-like protein (Toprh) was isolated from a piroplasm cDNA library of Theileria orientalis and its nucleotide sequence was determined. An open reading frame, encoding a polypeptide of 278 amino acid residues, was found in Toprh cDNA sequence. An intron of 89 bp was identified when this cDNA clone was compared with the Toprh gene in the genome of T. orientalis. The deduced amino acid sequence of Toprh shares 93.8, 93.1 and 69.1% identities with the prohibitins of T. parva (from chromosome 1), T. annulata (from chromosome 1), and Plasmodium falciparum, (from chromosome 10), respectively. By Western blot analysis, Toprh was found to be expressed in the piroplasm stage of the parasites.     

<Emphasis Type="Italic">Agrobacterium tumefaciens</Emphasis>-mediated transformation as a tool for random mutagenesis of <Emphasis Type="Italic">Colletotrichum trifolii</Emphasis>

We transformed Colletotrichum trifolii, the causal agent of alfalfa anthracnose, using Agrobacterium tumefaciens as a new tool for random insertional mutagenesis. Fungal spores of C. trifolii were transformed with T-DNA including the hygromycin phosphotransferase gene (hph). Southern analysis showed that every randomly selected transformant had a unique hybridization pattern of T-DNA, suggesting that the T-DNA was randomly integrated into the fungal genome. More significantly, about 75% of transformants had a single copy of the T-DNA. The results demonstrate that insertional mutagenesis via A. tumefaciens is a useful tool for studying the function of C. trifolii genes.     

A case of gastrinoma in a Shih-Tzu dog

A five-year-old male Shih-Tzu dog presented with severe vomiting and weight loss. The clinical signs were successfully improved by an eight-day treatment with an H(2)-receptor antagonist, gastrointestinal protectant and antibiotics. Ten days later, however, recurrence of vomiting was seen despite continuous medical treatment. Based on clinical signs and the results of various diagnostic tests including CBC, biochemical analysis, contrast radiography, and endoscopy, a duodenal or pancreatic neoplasm was suspected and exploratory laparotomy was conducted. Some swollen pancreatic regions were found, and biopsy of the pancreas indicated the diagnosis of a gastrin-secreting tumor. Consequently, based on a high serum gastrin level as well as clinical signs and immunohistological findings, we diagnosed the disease as canine gastrinoma, a rare tumor of the pancreas.     

Seroepidemiological study of canine ehrlichial infections in Yamaguchi prefecture and surrounding areas of Japan

Randomly selected serum samples from 150 dogs from Yamaguchi and neighbouring prefectures were subjected to the indirect immunofluorescent assay to detect antibodies against Ehrlichia canis, Ehrlichia chaffeensis, Ehrlichia muris and Ehrlichia from Ixodes ovatus. A total of 30 out of the 150 serum samples reacted with at least one of the antigens at a titer of 1:20 or more. Considerable cross-reactivity was seen and most samples reacted with at least two different antigens. Fifteen (10.0%) dogs had higher titers to E. canis than any of the other antigens. Four (2.7%) dogs had higher titers to Ehrlichia from Ixodes ovatus and one (0.6%) dog had higher titers to E. muris compared to the other antigens. The findings suggest that these five dogs may be infected with the domestic Ehrlichia of Japan. The remaining ten dogs had similar high titers to two or more of the antigens. This is the first serological evidence obtained of canine infection with the domestic Ehrlichia of Japan.     

Kid depletion in mouse oocytes associated with multinucleated blastomere formation and inferior embryo development

This study investigated the knockdown (KD) of Kid on maturation developmental competence and multinucleation of mouse germinal vesicle (GV) oocytes after parthenogenetic activation. Data revealed that Kid messenger RNA (mRNA) was expressed in GV and MII stage oocyte and 1‐ and 2‐cell embryos. Additionally, Kid mRNA expression in the Kid KD group decreased by nearly 46% compared to the control small interfering RNA (siRNA) groups. The rate of multinucleated embryos in the Kid KD group (52.4%) was significantly higher (P < 0.05) than the control siRNA group (4.7%). Finally, the developmental rates were significantly lower in the Kid siRNA group at > 4‐cell stage (28.6% vs. 53.5%) and the blastocyst stage (2.4% vs. 23.3%) compared to the control siRNA groups. Suppression of Kid using siRNA caused multinucleation in early embryos with high frequency and it may increase 2‐ to 4‐cell arrested embryos and reduce the developmental competence to blastocyst.