Effect of water temperature and chlorophyll abundance on shell growth of the Japanese pearl oyster, Pinctada fucata martensii, in suspended culture at different depths and sites   总被引：2，自引：0，他引：2  

Y Tomaru  Y Kumatabara  Z Kawabata  & S Nakano 《Aquaculture Research》2002,33(2):109-116

To understand the relationships between shell growth and some environmental factors, we examined the relationships between water temperature or chlorophyll abundance and the shell growth of the Japanese pearl oyster, Pinctada fucata martensii, suspended at three different depths at two sites. Growth in height, length and thickness of the shells were limited by water temperature during winter (< 20 °C), whereas growth in thickness correlated with food abundance, measured as chlorophyll, during early summer (> 20 °C). These results suggest that the shell of P. fucata martensii could grow well at locations with greater abundance of food and adequate water temperatures (20–26 °C), resulting in a longer growing season.  相似文献   

Isolation of chicken taste buds for real‐time Ca2+ imaging     

Ken‐ichi Kudo  Fuminori Kawabata  Toumi Nomura  Ayumi Aridome  Shotaro Nishimura  Shoji Tabata 《Animal Science Journal》2014,85(10):904-909

We isolated chicken taste buds and used a real‐time Ca²⁺ imaging technique to investigate the functions of the taste cells. With RT‐PCR, we found that isolated chicken taste bud‐like cell subsets express chicken gustducin messenger RNA. Immunocytochemical techniques revealed that the cell subsets were also immunopositive for chicken gustducin. These results provided strong evidence that the isolated cell subsets contain chicken taste buds. The isolated cell subsets were spindle‐shaped and approximately 61–75 μm wide and 88–98 μm long, and these characteristics are similar to those of sectional chicken taste buds. Using Ca²⁺ imaging, we observed the buds' response to 2 mmol/L quinine hydrochloride (a bitter substance) and their response to a mixture of 25 mmol/L L‐glutamic acid monopotassium salt monohydrate and 1 mmol/L inosine 5′‐monophosphate disodium salt, umami substances. The present study is the first morphological demonstration of isolated chicken taste buds, and our results indicate that the isolated taste buds were intact and functional approaches for examining the taste senses of the chicken using Ca²⁺ imaging can be informative.  相似文献   

Balenine,imidazole dipeptide,induces activation of superoxide dismutase in myotubes     

Yang  Min  Sun  Luchuanyang  Kawabata  Yasunosuke  Maegawa  Takahiro  Taniyama  Shigeto  Tachibana  Katsuyasu  Hirasaka  Katsuya 《Fisheries Science》2021,87(3):403-409

Balenine is one of the endogenous imidazole dipeptides. It is composed of beta-alanine and 3-methyl-l-histidine, which exist mainly in the muscles and the brain. The exact biological properties of balenine are still not well known, although the antioxidant activity of carnosine, another imidazole dipeptide, is known. In this study we investigated whether balenine exhibits antioxidant activity. It was found to decrease the superoxide anion (O₂⁻) and increased hydrogen peroxide (H₂O₂) generation. We found that SOD activity increased in balenine-treated C2C12 myotubes, although balenine did not increase expression of SOD mRNA. On the other hand, there were no changes in other antioxidant enzymes, CAT and GPX activity, and mRNA levels. In an in vitro assay, the direct activation of SOD treated by balenine was significantly higher than with carnosine treatment. Moreover, balenine constituent amino acids did not have the ability to activate SOD. Our results suggest that balenine contributes to antioxidant effects through activation of SOD.

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Molecular and genealogical analysis of grain dormancy in Japanese wheat varieties,with specific focus on MOTHER OF FT AND TFL1 on chromosome 3A     

Makiko Chono  Hitoshi Matsunaka  Masako Seki  Masaya Fujita  Chikako Kiribuchi-Otobe  Shunsuke Oda  Hisayo Kojima  Shingo Nakamura 《Breeding Science》2015,65(1):103-109

In the wheat (Triticum aestivum L.) cultivar ‘Zenkoujikomugi’, a single nucleotide polymorphism (SNP) in the promoter of MOTHER OF FT AND TFL1 on chromosome 3A (MFT-3A) causes an increase in the level of gene expression, resulting in strong grain dormancy. We used a DNA marker to detect the ‘Zenkoujikomugi’-type (Zen-type) SNP and examined the genotype of MFT-3A in Japanese wheat varieties, and we found that 169 of 324 varieties carry the Zen-type SNP. In Japanese commercial varieties, the frequency of the Zen-type SNP was remarkably high in the southern part of Japan, but low in the northern part. To examine the relationship between MFT-3A genotype and grain dormancy, we performed a germination assay in three wheat-growing seasons. On average, the varieties carrying the Zen-type SNP showed stronger grain dormancy than the varieties carrying the non-Zen-type SNP. Among commercial cultivars, ‘Iwainodaichi’ (Kyushu), ‘Junreikomugi’ (Kinki-Chugoku-Shikoku), ‘Kinuhime’ (Kanto-Tokai), ‘Nebarigoshi’ (Tohoku-Hokuriku), and ‘Kitamoe’ (Hokkaido) showed the strongest grain dormancy in each geographical group, and all these varieties, except for ‘Kitamoe’, were found to carry the Zen-type SNP. In recent years, the number of varieties carrying the Zen-type SNP has increased in the Tohoku-Hokuriku region, but not in the Hokkaido region.  相似文献   

Oxidative dimers produced from protocatechuic and gallic esters in the DPPH radical scavenging reaction     

Kawabata J  Okamoto Y  Kodama A  Makimoto T  Kasai T 《Journal of agricultural and food chemistry》2002,50(19):5468-5471

DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging reactions of protocatechuic and gallic acids, and their methyl esters, have been investigated by NMR. In acetone, methyl protocatechuate was gradually converted to a Diels-Alder adduct of two molecules of the intermediate quinone in the reaction with DPPH radical, whereas methyl gallate rapidly gave a symmetrical dimer via a putative quinone precursor. Both dimers are rather unstable and their structures have been deduced by in situ NMR measurements of the reaction mixtures. Gallic acid also gave a corresponding symmetrical dimer in the same reaction as methyl gallate, although protocatechuquinone produced from protocatechuic acid did not yield a Diels-Alder adduct, unlike its methyl ester. Interestingly, these dimer formations were not observed in methanol solution.  相似文献   

Nationwide Cyprinid herpesvirus 3 contamination in natural rivers of Japan     

Minamoto T  Honjo MN  Yamanaka H  Uchii K  Kawabata Z 《Research in veterinary science》2012,93(1):508-514

Cyprinid herpesvirus 3 (CyHV-3) disease is a significant threat for common and koi carp cultivators and for freshwater ecosystems. To determine the prevalence of CyHV-3 in Japanese rivers, a nationwide survey of all national class-A rivers was undertaken in the Summer of 2008. The virus was concentrated from river water samples using the cation-coated filter method. CyHV-3 DNA was detected in 90 rivers, representing 90% of 103 successfully analysed rivers. More than 100,000 copies of CyHV-3 DNA per litre of sample were detected in four rivers, higher than that reported during the Yura River outbreak in 2007. For CyHV-3-positive rivers, the log CyHV-3 density was negatively correlated with the water temperature on the sampling date and positively correlated with the suspended solids and dissolved oxygen, which are annually averaged for each river. Our results demonstrate that virus detection using molecular biology techniques is a powerful tool for monitoring the presence of CyHV-3 in natural environments.  相似文献   

Distribution of photoperiod-insensitive allele Ppd-A1a and its effect on heading time in Japanese wheat cultivars     

Masako Seki  Makiko Chono  Tsutomu Nishimura  Mikako Sato  Yasuhiro Yoshimura  Hitoshi Matsunaka  Masaya Fujita  Shunsuke Oda  Katashi Kubo  Chikako Kiribuchi-Otobe  Hisayo Kojima  Hidetaka Nishida  Kenji Kato 《Breeding Science》2013,63(3):309-316

The Ppd-A1 genotype of 240 Japanese wheat cultivars and 40 foreign cultivars was determined using a PCR-based method. Among Japanese cultivars, only 12 cultivars, all of which were Hokkaido winter wheat, carried the Ppd-A1a allele, while this allele was not found in Hokkaido spring wheat cultivars or Tohoku-Kyushu cultivars. Cultivars with a photoperiod-insensitive allele headed 6.9–9.8 days earlier in Kanto and 2.5 days earlier in Hokkaido than photoperiod-sensitive cultivars. The lower effect of photoperiod-insensitive alleles observed in Hokkaido could be due to the longer day-length at the spike formation stage compared with that in Kanto. Pedigree analysis showed that ‘Purple Straw’ and ‘Tohoku 118’ were donors of Ppd-A1a and Ppd-D1a in Hokkaido wheat cultivars, respectively. Wheat cultivars recently developed in Hokkaido carry photoperiod-insensitive alleles at a high frequency. For efficient utilization of Ppd-1 alleles in the Hokkaido wheat-breeding program, the effect of Ppd-1 on growth pattern and grain yield should be investigated. Ppd-A1a may be useful as a unique gene source for fine tuning the heading time in the Tohoku-Kyushu region since the effect of Ppd-A1a on photoperiod insensitivity appears to differ from the effect of Ppd-B1a and Ppd-D1a.  相似文献   

Probing a Coral Genome for Components of the Photoprotective Scytonemin Biosynthetic Pathway and the 2-Aminoethylphosphonate Pathway     

Eiichi Shoguchi  Makiko Tanaka  Takeshi Takeuchi  Chuya Shinzato  Nori Satoh 《Marine drugs》2013,11(2):559-570

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Optimization and validation of a flow cytometric method for immunophenotyping peripheral blood lymphocytes from cynomolgus monkeys (Macaca fascicularis)     

Baker DL  Finco-Kent DL  Reagan WJ  Conklyn MJ  Kawabata TT 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2008,37(1):42-48

BACKGROUND: Guidelines published by the Food and Drug Administration and Center for Human Medicinal Products describe the need to assess immunotoxic effects in nonclinical studies that evaluate drug toxicity, including the use of immunophenotyping to measure immunotoxicity. We are not aware of previous studies, however, that have validated methods for immunophenotyping peripheral blood lymphocyte subsets in whole blood samples from cynomolgus monkeys. OBJECTIVE: The purpose of this study was to optimize and validate a flow cytometric assay for immunophenotyping lymphocytes in the peripheral blood of cynomolgus monkeys. METHODS: A series of prevalidation experiments were done to determine optimal reagents, volumes, timing, and other procedural details of the flow cytometric assay. Using the optimized method, we then determined precision, interindividual variation, laboratory-to-laboratory variability, and sample stability. Stabilized human blood was used as a positive control for staining, processing, and analysis. The percentage and number of pan-T cells (CD3+), T-helper cells (CD3+4+), T cytotoxic/suppressor cells (CD3+8+), natural killer cells (CD3-16+), and B-cells (CD3-20+) were determined in 146 male and 140 female, clinically healthy monkeys and reference intervals were calculated. RESULTS: By doing 4-color staining with a lyse-wash method, intra- and interassay precision were <5% for all lymphocyte subsets. Variability between technicians and laboratories was minimal (CVs<3%). Samples were stable for up to 24 hours after staining and fixing. CONCLUSIONS: The validated method is extremely robust and can be performed under good laboratory practice conditions to support nonclinical studies. Reference intervals for lymphocyte subsets were similar to those previously reported.  相似文献   

A Comparison of the Plasma Fructose Concentrations in Dogs and Cats and Changes in the Fructose Concentrations in Dogs Following Intravenous Administration of Fructose     

Arai  T.  Hashimoto  K.  Muzutani  H.  Kawabata  T.  Sako  T.  Washizu  T. 《Veterinary research communications》1999,23(4):203-209

The plasma concentrations of fructose, glucose, free fatty acids (FFA) and triglycerides (TG) were measured in dogs and cats. Changes in these concentrations were investigated in dogs by an intravenous fructose tolerance test (IVFTT) at a dose of 0.1 g/kg body weight. Fructose concentrations in the plasma of dogs were significantly higher than those of cats. There was no significant difference in plasma glucose concentrations between dogs and cats. Plasma FFA concentrations decreased and TG concentrations increased after feeding in both dogs and cats. During the IVFTT, the plasma fructose concentrations in the dogs increased rapidly to a peak by 2 min and then decreased to half of the peak by 5 min after the administration of fructose. Administration of fructose resulted in an increase in the plasma TG concentrations and reduced plasma FFA concentrations in the dogs. Only 4% of the administered fructose was detected in the urine of dogs following IVFTT. Plasma fructose was considered to be rapidly absorbed and metabolized in both dogs and cats. However, as with glucose metabolism, there appear to be some differences in fructose metabolism between dogs and cats.  相似文献