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41.
Bhuminad DEVKOTA Masahiro TAKAHASHI Saori SATO Kouya SASAKI Atsushi UEKI Takeshi OSAWA Masahiro TAKAHASHI Norio YAMAGISHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(7):875-878
Blood samples were obtained sequentially from 10 dairy cows around the time of
parturition to assess plasma fluctuations in estradiol-17β (E2) levels in
association with those of several bone resorption markers. Plasma E2
concentration increased sharply a few days prepartum and decreased quickly after
parturition. In terms of bone resorption markers, the plasma level of tartrate-resistant
acid phosphatase isoform 5b (TRAP5b) rose significantly, commencing 1 week prepartum, and
was maintained at this level to a few days postpartum. The plasma concentration of
carboxyterminal collagen cross-links of type-I collagen (CTx) increased significantly
after parturition. These observations suggest that osteoclast-mediated bone resorption was
activated after parturition when plasma E2 concentrations decreased. 相似文献
42.
Atsushi IDETA Yoshito AOYAGI Kanami TSUCHIYA Yuuki NAKAMURA Kou HAYAMA Atsushi SHIRASAWA Kenichiro SAKAGUCHI Naomi TOMINAGA Yoshiyuki NISHIMIYA Sakae TSUDA 《The Journal of reproduction and development》2015,61(1):1-6
Embryos obtained via superovulation are necessary for mammalian artificial reproduction, and viability is a key determinant of success. Nonfreezing storage at 4 C is possible, but currently used storage solutions can maintain embryo viability for only 24–48 h. Here we found that 10 mg/ml antifreeze protein (AFP) dissolved in culture medium 199 with 20% (v/v) fetal bovine serum and 25 mM HEPES could keep bovine embryos alive for 10 days at 4 C. We used a recombinant AFP isolated from the notched-fin eelpout (Zoarces elongatus Kner). Photomicroscopy indicated that the AFP–embryo interaction was enhanced at 37 C. Embryos pre-warmed with the AFP solution at 37 C for 60 min maintained high viability, whereas those that were not pre-warmed could live no longer than 7 days. Thus, short-term storage of bovine embryos was achieved by a combination of AFP-containing medium and controlled pre-warming. 相似文献
43.
Takafumi SUZUKI Naohito NISHII Satoshi TAKASHIMA Tatsuya MATSUBARA Atsushi IWASAWA Hirofumi TAKEUCHI Kohei TAHARA Tatsuyuki HACHISU Hitoshi KITAGAWA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(11):1379-1383
Polyclonal immunoglobulin (Ig) G autoantibodies against insulin have been
identified in sera of healthy cats. We purified and fractionated insulin-binding IgGs from
cat sera by affinity chromatography and analyzed affinity of insulin-binding IgGs for
insulin and their epitopes. Following the passing of fraction A, which did not bind to
insulin, insulin-binding IgGs were eluted into two fractions, B and C, by affinity
chromatography using a column fixed with bovine insulin. Dissociation constant (KD) values
between insulin-binding IgGs and insulin, determined by surface plasmon resonance analysis
(Biacore™system), were 1.64e−4 M for fraction B (low affinity IgGs) and
2e−5 M for fraction C (high affinity IgGs). Epitope analysis was conducted
using 16 peptide fragments synthesized in concord with the amino acid sequence of feline
insulin by an enzyme-linked immunosorbent assay. Fractions B and C showed higher
absorbance (affinity) of the peptide fragment of 10 amino acid residues at the
carboxyl-terminal of the B chain (peptide No. 19), followed by peptide fragments of 6 to
15 amino acid residues of the B chain (peptide No. 8). Fraction C showed a higher
absorbance to 7 to 16 amino acid residues of the B chain (peptide No. 5) compared with the
absorbance of fraction B. Polyclonal insulin-binding IgGs may form a macromolecule complex
with insulin through the multiple affinity sites of IgG molecules. Feline insulin-binding
IgGs are multifocal and may be composed of multiple IgG components and insulin. 相似文献
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47.
Asahi HORINAKA Yo-Han KIM Atsushi KIMURA Eiji IWAMOTO Tatsunori MASAKI Toshihiro ICHIJO Shigeru SATO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(7):1098
We investigated changes in the predicted functions of the rumen bacterial community in Japanese Black beef cattle during fattening. Nine cattle were fed a high-concentrate diet during the early, middle, and late fattening stages consecutively (10–14, 15–22, and 23–30 months of age, respectively). The rumen fluid and solid samples collected at each stage were subjected to sequencing analyses. The sequencing results were clustered and classified into operational taxonomic units (OTUs). Representative sequences and a raw counting table for each OTU were submitted to the Piphillin website. The predicted functions were revealed by the Kyoto Encyclopedia of Genes and Genomes database as the ratio of the total sequence. In the early stage, “Biosynthesis of secondary metabolites” was significantly higher in the fluid fraction than in the solid fraction. “Two-component system” in the middle stage was significantly lower and “Purine metabolism” in the late stage was significantly higher in the fluid fraction than those in the solid fraction. The fluid fraction was significantly correlated with acetic acid, propionic acid, and bacterial metabolism, such as “Biosynthesis of secondary metabolites” and “Sugar metabolism.” Moreover, the solid fraction was correlated with “Purine metabolism” and “Biosynthesis of secondary metabolism”. These results suggest that the rumen bacterial community in Japanese Black beef cattle adapts to changes in rumen conditions by altering their functions in response to a long-term high-grain diet. 相似文献
48.
Kodama S Yamamoto A Sato A Suzuki K Yamashita T Kemmei T Taga A Hayakawa K 《Journal of agricultural and food chemistry》2007,55(16):6547-6552
Chiral resolution of isoxanthohumol (IX) in beer samples was performed by hydroxypropyl-gamma-cyclodextrin-modified micellar electrokinetic chromatography. The optimum running conditions were found to be 20 mM phosphate buffer (pH 7.0) containing 45 mM hydroxypropyl-gamma-cyclodextrin and 100 mM sodium dodecyl sulfate with an effective voltage of +20 kV at 20 degrees C using direct detection at 210, 295, and 370 nm. IX was detected in 12 beer samples and the total levels of (+)- and (-)-IX ranged from 0.15 to 1.4 mg/L. But the amount of xanthohumol (XN) was below the detection limit (0.017 mg/L). Each level of (-)-IX was almost the same as that of (+)-IX, suggesting that IX was a racemic mixture in these beer samples. The racemization of IX in beer could be attributed to the production of a racemic mixture from XN during boiling and to the fact that IX enantiomers were easily interconverted. 相似文献
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50.
Reduction of transport stress of ayu by obligated schooling 总被引:3,自引:0,他引:3
KEI'ICHIRO IGUCHI FUMINARI ITO KOGI OGAWA NAOTO MATSUBARA TAIGA YODO TSUGIKO YAMASAKI 《Fisheries Science》2002,68(4):849-853
We investigated stress responses of ayu Plecoglossus altivelis under the hypothesis that overcrowding during transport can be a stressor and the stress predisposes fish to disease by decline in immunocompetence. The extent of stress response was determined under different fish densities. As inferred from the serum concentration of cortisol 1 day after the treatment, the density at more than 23 kg/m3 , which was within the range of normal transporting procedures, acutely evoked intense stress responses. To examine a possible way to reduce the stress response of fish under crowding conditions, we compared two fish groups established in water tanks with circulating (whirling) and turbulent currents at the same density. The cortisol levels 1 day after the treatment were 2.5-fold higher in turbulent current than in whirling current. Fish in whirling current formed a school, while those in turbulent current aggregated with each other. Schooling of fish induced by water flow may reduce their stress responses during transport. A transport system with a directional water flow should keep fish in good condition without reducing the number of fish contained. 相似文献