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Hidetaka Sato

Publications and source records attributed to Hidetaka Sato.

15 recordsLinked to original sources
PubMed2006

Suppression of azoxymethane-induced colon cancer development in rats by a cyclooxygenase-1 selective inhibitor, mofezolac.

We demonstrated recently that mofezolac, a cyclooxygenase-1 (COX-1) selective inhibitor, suppresses the development of azoxymethane (AOM)-induced colonic aberrant crypt foci in F344 rats and intestinal polyps in APC1309 mice. In the present study, we therefore investigated the effects of mofezolac on colon cancer development. Male F344 rats were injected subcutaneously with 15 mg/kg body weight of AOM in the back twice at 7-day intervals from 5 weeks of age, and fed a diet containing 600 or 1200 ppm mofezolac for 32 weeks, starting 1 day before the first dosing of AOM. Treatment with 1200 ppm mofezolac significantly reduced the incidence, multiplicity and volume of colon carcinomas to 79%, 2.15 +/- 1.65 and 7.5 +/- 11.8 mm3, respectively, compared with 94%, 3.19 +/- 1.87 and 23.7 +/- 31.2 mm3 in the AOM treatment alone. Administration of 600 ppm mofezolac showed only a slight reduction. No side effects were observed in any of the groups. These results confirm that COX-1, as well as COX-2, contributes to colon carcinogenesis and that mofezolac may be a good chemopreventive agent for human colon cancer.

Animals↗
PubMed2006

Detection method for genetically modified papaya using duplex PCR.

A simple and rapid method for the identification of genetically modified (GM) papaya, derived from Line 55-1, was developed by modifying the Japanese official PCR method. Genomic DNA was directly extracted from the fresh fruit without the lyophilization step, using a commercial silica-based kit. To develop a duplex PCR method which simultaneously detects the GM papaya-specific gene and the intrinsic papain gene, the papain 2-5'/3' (amplicon size; 184 bp) primer pair for the detection of the papain gene was newly designed within the region of the products (211 bp) amplified using the papain 1-5'/-3' primer pair adopted in the Japanese official PCR method. To detect the GM papaya-specific gene, the primer pair Nos C-5'/CaM N-3' described in the Japanese official method was used. The DNA sequences of the GM papaya gene and the intrinsic papain gene were co-amplified using the PCR method in a single tube. The developed duplex PCR method allows the simultaneous detection of the products by means of agarose gel electrophoresis or microchip electrophoresis. The proposed method for GM papaya identification is simple and rapid.

Carica↗
PubMed2006

[Detection of short tandem repeat (STR) polymorphisms by microchip electrophoresis for individual identification of cattle].

A simple and rapid detection of short tandem repeat (STR) markers was studied as a screening test for individual identification of cattle. DNAs were extracted from eight commercial beef samples by a proteinase K-boil method followed by purification with 2-propanol precipitation. Five STR markers, known to be highly polymorphic, were amplified by PCR and analyzed both by a conventional sequencing analysis (SEQ) and by a proposed microchip electrophoresis (MEP). Every marker revealed high polymorphism, such as 5-9 alleles in SEQ analysis, and 4-6 alleles in MEP analysis. This simple and rapid MEP analysis is expected to be an effective screening tool with use of confirmatory SEQ analysis.

Animal Identification Systems↗
PubMed2005

Suppressive effect of an inducible nitric oxide inhibitor, ONO-1714, on AOM-induced rat colon carcinogenesis.

The expression of inducible nitric oxide synthase (iNOS) is markedly elevated in rat colon cancers induced by azoxymethane (AOM). In addition, iNOS can be detected in most adenomas and dysplastic aberrant crypt foci (ACF), suggesting that iNOS plays an important role in colon carcinogenesis. In the present study, the effect of an iNOS inhibitor, ONO-1714 ((1S,5S,6R,7R)-7-chloro-3-imino-5-methyl-2-azabicyclo[4.1.0] heptane hydrochloride), on AOM-induced rat colon carcinogenesis was investigated. Male F344 rats were treated with 15 mg/kg body weight of AOM once a week, for 2 weeks. ONO-1714 was given to the rats at doses of 10, 20, 50, and 100 ppm in diet for 4 weeks from the day before the first carcinogen treatment. The number of AOM-induced ACF in the rats receiving 10, 20, 50 and 100 ppm ONO-1714 were 94, 73 (P < 0.05), 71 (P < 0.005), and 53% (P < 0.0005), respectively, of the control value. Moreover, the mean number of aberrant crypts per focus was significantly lowered in 100 ppm ONO-1714 group (P < 0.05). Then, the effects of long-term treatment (32 weeks) with 50 and 100 ppm ONO-1714 on AOM-induced colorectal tumor development were examined. Although incidences and multiplicities of colon tumors did not significantly differ among the groups, number of tumors developing in the middle part of colon were reduced with both 50 and 100 ppm doses (P < 0.05). Furthermore, colon tumor volume tended to be decreased by ONO-1714 treatment, and the number of colon tumors more than 3mm in diameter was significantly lowered in the 100 ppm ONO-1714 group (P < 0.01). These results suggest that iNOS plays roles in both early and late stages of colon carcinogenesis.

Amidines↗
PubMed2005

Prostaglandin E receptor EP3 deficiency modifies tumor outcome in mouse two-stage skin carcinogenesis.

We have recently shown that the prostaglandin E(2) (PGE(2)) receptor EP(3) plays an important role in suppression of colon cancer cell proliferation and that its deficiency enhances late stage colon carcinogenesis. Here we examined the effects of EP(3)-deficiency on two-stage skin carcinogenesis. 7,12-Dimethylbenz[a]anthracene (50 microg/200 microl of acetone) was thus applied to the back skin of female EP(3)-knockout and wild-type mice at 8 weeks of age, followed by treatment with 12-O-tetradecanoylphorbol-13-acetate (5 microg/200 microl of acetone) twice a week for 25 weeks. First tumor appearance was observed in EP(3)-knockout mice at week 10, which was 3 weeks later than in EP(3) wild-type mice, and multiplicity observed at week 11 was significantly lower in the EP(3)-knockout case. However, histological examination showed that the tumor incidence and multiplicity at week 25 were not significantly changed in knockout mice and wild-type mice (incidence, 19/19 versus 23/24; multiplicity, 3.58 +/- 0.51 versus 3.17 +/- 0.63, respectively). Interestingly, there were no squamous cell carcinomas (SCCs) in the EP(3)-knockout mice, while SCCs were observed in 3 out of 24 wild-type mice. Furthermore, benign keratoacanthomas only developed in EP(3)-knockout mice (6/19 versus 0/24, P < 0.01). The results suggest that PGE(2) receptor EP(3) signaling might contribute to development of SCCs in the skin.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed2005

Anomalous internal carotid anastomosis to contralateral anterior cerebral artery.

BACKGROUND: Many anomalies and variants in vascular anatomy have been reported in relation to the anterior cerebral artery (ACA). PATIENTS AND METHODS: We encountered an apparently novel anomaly in a 30-year-old man admitted for disturbance of consciousness following a traffic accident. Computed tomography revealed an acute subdural hematoma and subarachnoid hemorrhage. RESULTS AND CONCLUSIONS: No vascular abnormalities related to the hemorrhage were detected by conventional angiography, so we concluded that the bleeding was of traumatic origin. Anomalous origin of the ACA was disclosed incidentally, with both A1 segments arising from the right internal carotid artery; no normal A1 segment of the left ACA was visualized. We discuss possible bases for this anomalous origin.

Accidents, Traffic↗
PubMed2005

Suppression of azoxymethane-induced colon cancer development in rats by a prostaglandin E receptor EP1-selective antagonist.

Prostaglandin E(2) is involved in colon carcinogenesis through its binding to the PGE(2) receptor subtypes EP(1), EP(2), EP(3) and EP(4). We have demonstrated that administration of ONO-8711, an EP(1)-selective antagonist, suppresses development of AOM-induced ACF in C57BL/6 mice and F344 rats. ONO-8711 also reduced the numbers of intestinal polyps in Min mice. In the present study, we investigated the long-term effects of ONO-8711 on colon cancer development in rats treated with AOM. Male F344 rats were injected subcutaneously with AOM (15 mg/kg body weight) once a week for the first 2 weeks to develop colon cancer. Administration of 400 or 800 p.p.m. ONO-8711 in their diets for 32 weeks reduced the incidence, multiplicity and volume of colon carcinomas. The incidence of colon adenocarcinomas in AOM-treated rats was 97, 83 and 76% (P < 0.05) in the 0, 400 and 800 p.p.m. of ONO-8711 groups, respectively. The multiplicity of adenocarcinomas was also decreased significantly, being 3.31 +/- 0.33, 2.34 +/- 0.27 (P < 0.05) and 2.06 +/- 0.34 (P < 0.01) with 0, 400 and 800 p.p.m. of ONO-8711, respectively. Moreover, treatment with 800 p.p.m. ONO-8711 reduced the mean volume of adenocarcinomas to 49% (P < 0.05) of the value for the AOM treatment alone. Furthermore, the BrdU labeling index was decreased significantly in colon cancer cells by 800 p.p.m. ONO-8711. These results confirm that EP(1) is involved in colon carcinogenesis and that EP(1)-selective antagonists might be promising candidates for colon cancer chemopreventive agents.

Animals↗
PubMed2004

Tie2/angiopoietin-1 signaling regulates hematopoietic stem cell quiescence in the bone marrow niche.

The quiescent state is thought to be an indispensable property for the maintenance of hematopoietic stem cells (HSCs). Interaction of HSCs with their particular microenvironments, known as the stem cell niches, is critical for adult hematopoiesis in the bone marrow (BM). Here, we demonstrate that HSCs expressing the receptor tyrosine kinase Tie2 are quiescent and antiapoptotic, and comprise a side-population (SP) of HSCs, which adhere to osteoblasts (OBs) in the BM niche. The interaction of Tie2 with its ligand Angiopoietin-1 (Ang-1) induced cobblestone formation of HSCs in vitro and maintained in vivo long-term repopulating activity of HSCs. Furthermore, Ang-1 enhanced the ability of HSCs to become quiescent and induced adhesion to bone, resulting in protection of the HSC compartment from myelosuppressive stress. These data suggest that the Tie2/Ang-1 signaling pathway plays a critical role in the maintenance of HSCs in a quiescent state in the BM niche.

Angiopoietin-1↗
PubMed2004

[Inter-laboratory evaluation studies for development of notified ELISA methods for allergic substances (milk)].

Extracts of sausage, sauce, cookie, cereal and pasta sauce spiked with milk standard protein at a level of 5-20 ng/mL as sample solutions were analyzed in replicate in 10 laboratories. Coefficients of variation (CVs) of the three ELISA methods using a Milk Protein Casein ELISA Kit (Casein kit), a Milk Protein Beta-Lactoglobulin ELISA Kit (Beta-Lactoglobulin kit) and a FASTKIT Milk ELISA Kit (Milk ELISA kit) were mostly below 10%. Mean recoveries of the milk standard protein from the food extracts were over 40% in the three ELISA methods with a few excertions. The recoveries of milk standard protein from the sauce extract in Casein kit were improved by adjusting the extract to neutrality before the Casein kit assay. The recoveries of milk standard protein from cookie, cereal and pasta sauce were improved by the increasing the amount of antibody coated in the Milk ELISA kit. The detection limits of all the ELISA methods were 1 ng/mL in sample solutions. These results suggested that the notified ELISA methods are reliable and reproducible for the inspection of milk protein levels in extracts of sausage, sauce, cookie, cereal and pasta sauce.

Allergens↗
PubMed2004

[Inter-laboratory evaluation studies for development of notified ELISA methods for allergic substances (wheat)].

Extracts of sausage, sauce, pasta sauce, fish paste and cereal spiked with wheat standard protein at a level of 5-20 ng/mL as sample solutions were analyzed in replicate in 10 laboratories. Coefficients of variation (CVs) of both ELISA methods using a Wheat Protein ELISA Kit (Gliadin kit) and a FASTKIT Wheat ELISA Kit (Wheat ELISA kit) were mostly below 10%. Mean recoveries of the wheat standard protein from the food extracts were over 40% in the two ELISA methods except those from cereal extract determined using the Wheat ELISA kit. Repeatability relative standard deviations of wheat standard protein in the five food extracts were in the ranges of 16-26.9% and 3.7-36.2% for the Gliadin kit and the Wheat ELISA kit, respectively. Reproducibility relative standard deviations of wheat standard protein in the five food extracts were 21.6-38.5%, 29.7-53.8% for the Gliadin kit and the Wheat ELISA kit, respectively. The recoveries of wheat standard protein from the cereal extract were improved by the increasing the amount of antibody coated on the plate in the Wheat ELISA kit. The detection limits of both ELISA methods were 1 ng/mL in sample solutions. These results suggested that the notified ELISA methods are reliable and reproducible for the inspection of wheat protein levels in extracts of sausage, sauce, pasta sauce, fish paste and cereal.

Allergens↗
PubMed2004

[Inter-laboratory evaluation studies for establishment of notified ELISA methods for allergic substances (buckwheat)].

Inter-laboratory evaluation studies were conducted for the ELISA methods for allergic substances (buckwheat). Extracts of snack, bun and udon spiked with buckwheat standard protein at a level of 5-20 ng/mL as sample solutions were analyzed in replicate at 10 laboratories. Coefficients of variation (CVs) of the ELISA methods using a Buckwheat Protein ELISA Kit (Buckwheat kit) and a FASTKIT Buckwheat ELISA kit (Buckwheat ELISA kit) were mostly below 10%. Mean recoveries of the buckwheat standard protein from the food extracts were over 40% in the two ELISA methods. Repeatability relative standard deviations of buckwheat standard protein in three food extracts were in the ranges of 6.8-78.5% and 5.0-33.9% for the Buckwheat kit and the Buckwheat ELISA kit, respectively. Reproducibility relative standard deviations of buckwheat standard protein in three food extracts were 11.9-69.5% and 16.5-34.1% for the Buckwheat kit and the Buckwheat ELISA kit, respectively. The detection limits of both ELISA methods were 1 ng/mL in sample solutions. These results suggest that the notified ELISA methods are reliable and reproducible for the inspection of buckwheat protein levels in extracts of snack, bun and udon.

Allergens↗
PubMed2004

[Inter-laboratory evaluation studies for establishment of notified ELISA methods for allergic substances (peanuts)].

Inter-laboratory evaluation studies were conducted for ELISA methods for allergic substances (peanuts). Extracts of biscuit, sauce, chocolate and butter spiked with peanut standard protein at a level of 5-20 ng/mL as sample solutions were analyzed in replicate in 10 laboratories. Coefficients of variation (CVs) of the ELISA methods using a Peanut Protein ELISA Kit (Peanut kit) and a FASTKIT Peanut ELISA kit (Peanut ELISA kit) were mostly below 10%. Mean recoveries of the peanut standard protein from the food extracts were over 40% in the two ELISA methods. Repeatability relative standard deviations of peanut standard protein in four food extracts were in the ranges of 15.2-49.7% and 3.0-28.3% for the Peanut kit and the Peanut ELISA kit, respectively. Reproducibility relative standard deviations of peanut standard protein in four food extracts were 23.5-44.4%, 9.6-28.4% for the Peanut kit and the Peanut ELISA kit, respectively. The detection limits of both ELISA methods were 2-2.5 ng/mL in sample solutions. These results suggested that the notified ELISA methods are reliable and reproducible for the inspection of peanut protein levels in extracts of biscuit, sauce, chocolate and butter.

Allergens↗
PubMed2003

[Inter-laboratory evaluation studies of notified ELISA methods for allergic substances (egg)].

Inter-laboratory evaluation studies were conducted for the notified ELISA methods for allergic substances (Egg). Standard extracts of egg spiked in extracts of sausage, sauce, cookie, bread and cereal at a level of 5-20 ng/mL as the sample solution were analyzed in replicate in 10 laboratories. Coefficients of variation (CVs) of all three ELISA methods using an Egg Protein ovalbumin ELISA Kit (ovalbumin kit), an Egg Protein ovomucoid ELISA Kit (ovomucoid kit) and a FASTKIT Egg ELISA kit (Egg ELISA kit) were mostly less than 10%. Mean recoveries of the standard extract of egg were over 40% in the three ELISA methods. Repeatability relative standard deviations of egg standard solution in five food extracts were in the ranges of 18.7-25.5%, 18.6-41.8%, 21.3-43.3% for the ovalbumin kit, the ovomucoid kit and the Egg ELISA kit, respectively. Reproducibility relative standard deviations of egg standard solution in five food extracts were 16.8-35.1%, 19.6-35.8%, 24.7-51.1% for the ovalbumin kit, the ovomucoid kit and the Egg ELISA kit, respectively. The detection limits of all the ELISA methods were 4-5 ng/mL in sample solutions. These results suggested that the notified ELISA methods are reliable and reproducible for the inspection of egg protein levels in extracts of sausage, sauce, cookie, bread and cereal.

Allergens↗
PubMedDate not supplied

Interlaboratory evaluation of two enzyme-linked immunosorbent assay kits for the detection of egg, milk, wheat, buckwheat, and peanut in foods.

The labeling of 5 major allergenic ingredients (egg, milk, wheat, buckwheat, and peanut) is mandatory in Japan, and 2 series of enzyme-linked immunosorbent assay (ELISA) kits have been established as official screening methods. However, these official methods have not provided the necessary sensitivity, due in part to poor extraction efficiency. To address this need, 2 novel ELISA kits have been developed: the FASTKIT ELISA Ver. II Series and the FASPEK Allergenic Substances Detection Kit. The new kit systems use an improved extraction buffer that can extract insoluble proteins produced by processing and feature new antibodies that bind to the denatured proteins extracted with the new extraction buffer. The analytical performances of the 2 new ELISA kit series were evaluated in an interlaboratory study. Ten laboratories participated in the study and determined the major allergenic ingredients contained in 5 types of model processed food. The 2 ELISAs displayed fairly good reproducibility and sufficient recovery.

Allergens↗