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11.
ABSTRACT: The thermal stability of carp G-actin was investigated by monitoring loss of actin polymerization ability. To determine the amount of native actin remaining after heat treatment, actin was labeled with a fluorescence reagent, N-(1-pyrene)iodoacetamide. The loss of polymerization ability of carp actin during heat treatment, at between 45 and 55°C, occurred faster than that of chicken actin. The inactivation rate was influenced by concentrations of ATP and Ca2+ in solution. With the increase of Ca2+ concentration, the inactivation of carp actin was markedly suppressed. Furthermore, the activation energy of the inactivation of carp actin obtained from an Arrhenius plot was similar to that of chicken actin. These results indicated that the thermal instability of carp G-actin was due to the low affinites of ATP and Ca2+ for carp actin described in a previous report. 相似文献
12.
γ-Oryzanol is a main oleophilic component in rice bran oil and has been well recognized as a good dietary supplement for human health, as well as having uses in industrial materials. japonica-type rice cultivars generally showed significantly higher contents of total γ-oryzanol in brown rice compared with indica-type cultivars, although within-group variation was significant. The objective of this study was to explore quantitative trait loci (QTLs) responsible for the difference in the γ-oryzanol content between japonica-type and indica-type rice cultivars, using recombinant inbred lines (RILs), backcross inbred lines (BILs), and corresponding chromosome segment substitution lines (CSSLs) derived from crosses between japonica-type and indica-type. Results from RILs and BILs showed that eight QTLs were detected with R2 from .09 to .16. Nine candidate regions for QTL were also suggested from corresponding CSSLs. These QTLs from RILs and BILs and the candidate regions from CSSLs were not overlapped, although one QTLs was mapped near the boundaries of the respective candidate region. At four QTLs and three candidate regions, alleles or segments from japonica-type caused higher contents than those from indica-type. On the other hand, at the other four QTLs and six candidate regions, alleles or segments from indica-type caused higher contents than those from japonica-type, which is a reverse result to the parental differences. This result strongly suggested that alleles with increasing effects on γ-oryzanol content could be accumulated not only from japonica-type but also from indica-type, leading to a potential for increase in γ-oryzanol content in future breeding programs. 相似文献
13.
Yano S Umeda D Maeda N Fujimura Y Yamada K Tachibana H 《Journal of agricultural and food chemistry》2006,54(14):5203-5207
Flavonoids ubiquitously exist in plants, vegetables, fruits, and teas. We evaluated the effect of dietary apigenin, one of the well-known flavonoids, on the immune system in C57BL/6N mice. Mice were fed experimental diets containing apigenin for 2 weeks. After the experimental period, there was no significant difference in body and organ weights between the control and the apigenin group. The total immunoglobulin (Ig) E levels in mice fed apigenin were significantly suppressed, whereas levels of IgG, IgM, and IgA were not affected. We also examined the effect of the apigenin diet on cytokine expression in mice sera using a cytokine array. The production of regulated upon activation normal T cell expressed and secreted (RANTES) and soluble tumor necrosis factor receptor I (sTNFRI) in mice sera was down-regulated by the apigenin diet. These results suggest that a diet containing apigenin can reduce serum IgE and inflammatory cytokines such as RANTES and sTNFRI in mice. 相似文献
14.
Kinetic Parameters of Gross N Mineralization of Peat Soils as Related to the Composition of Soil Organic Matter 总被引:1,自引:0,他引:1
Bentio Heru Purwanto Akira Watanabe Jong Foh Shoon Ken-ichi Kakuda Ho Ando 《Soil Science and Plant Nutrition》2005,51(1):109-115
Peat land has been considered as an alternative type of land for agricultural development especially in the tropics. In the present study, the N-supplying capacity, one of the most important soil properties in terms of crop production, of peat soils was examined. Ten peat soil samples were collected from Indonesia, Malaysia, and Japan. Gross N mineralization in the soil samples was estimated using a zero-order model, and kinetic parameters of mineralization were determined using a simple type model. Soil organic matter composition was investigated using 13 C CPMAS NMR. Mineralization potential ( N 0 ), apparent activation energy ( E a ), and mineralization rate constant ( k ) ranged between 571–2,445 mg kg−1 , 281–8,181 J mol−1 , and 0.009–0.020 d−1 , respectively. Although none of the parameters showed a significant correlation with the soil C/N ratio, a negative correlation was observed between the k value and the ratio of the proportion of alkyl C in total C to that of O -alkyl C estimated by 13 C CPMAS NMR. The latter suggested that the k values were higher in the peat soils relatively rich in readily decomposable organic matter including carbohydrates. 相似文献
15.
Chemical characteristics and potential source of fulvic acids leached from the plow layer of paddy soil 总被引:2,自引:0,他引:2
To understand better the chemical characteristics and source of dissolved organic matter (DOM) leached from the plow layer of rice paddies, a lysimeter study was conducted, which simulated submerged paddy topsoil during rice growth. The fulvic acid (FA) fraction in the percolation water from the lysimeter was collected by adsorption onto insoluble polyvinylpyrrolidone (PVP), and the temporal variations in its elemental composition, molecular size distribution, IR spectra, 13C CPMAS NMR spectra, and δ13C values were investigated. The proportion of the FA fraction to bulk DOM varied greatly, but the chemical characteristics of the FA fraction did not change appreciably during the experimental period. Thus, it is considered that the changes in the DOM composition in percolation water were mainly due to the differing contributions of the FA fraction. Further, to investigate the source of the FA fraction in the leachate, the chemical characteristics of the FA fraction in the leachate were compared with those extracted from the plow layer soil. A sequential extraction of the FA fraction was conducted using a sequence of water, 0.25 M Na2SO4, 0.1 M Na4P2O7 (pH 7.0), 0.1 M Na4P2O7 (pH 10.5), and NaBH4+0.1 M Na4P2O7 (pH 10.5). It was found that the water- and 0.25 M Na2SO4-extractable fractions, which were most mobile, were not the only source of the FA fraction in the leachate. The small molecular size sub-fraction of the NaBH4+0.1 M Na4P2O7 (pH 10.5)-extractable FAs, most of which are probably bound mainly to iron oxides, are considered to be another source of the FA fraction leached from the plow layer of paddy fields. 相似文献
16.
Shintaro TOMURA Atsushi TOSHIMA Akira NOMURA Masahiko HIRATA Tetsushi YAMAGAMI Yumiko KAGAWA Tsuyoshi KADOSAWA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(3):439
An 11-year-old neutered male Domestic Shorthair cat presented with a 3-month history of hypoglycemia, two episodes of seizure, and intermittent tick-like signs. Serum biochemistry revealed severe hypoglycemia associated with high insulin concentrations. Dynamic abdominal computed tomography (CT) indicated two pancreatic masses, which were enhanced most during the late arterial phase but had different degrees and variations of attenuation. Partial pancreatectomy was performed. Histopathology and immunohistochemistry confirmed that one mass was an insulinoma and the other was an ectopic splenic tissue, consistent with the differences in imaging findings. When an intrapancreatic lesion with hyper-attenuation on dynamic abdominal CT is detected, not only insulinoma or metastasis of malignancies but also intrapancreatic accessory spleen (IPAS) should be considered as differential diagnoses. 相似文献
17.
Hiroshi UENO Osamu YAMATO Takeshi SUGIURA Moeko KOHYAMA Akira YABUKI Kenjiro MIYOSHI Kazuya MATSUDA Tsuyoshi UCHIDE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(1):91-95
A male Japanese domestic cat with retarded growth in Hokkaido, Japan, showed
progressive motor dysfunction, such as ataxia starting at 3 months of age and tremors,
visual disorder and seizure after 4 months of age. Finally, the cat died of neurological
deterioration at 9 months of age. Approximately half of the peripheral blood lymphocytes
had multiple abnormal vacuoles. Magnetic resonance imaging showed bisymmetrical
hyperintensity in the white matter of the parietal and occipital lobes in the forebrain on
T2-weighted and fluid-attenuated inversion recovery images, and mild encephalatrophy of
the olfactory bulbs and temporal lobes. The activity of lysosomal acid β-galactosidase in
leukocytes was negligible, resulting in the biochemical diagnosis of GM1 gangliosidosis.
Histologically, swollen neurons characterized by accumulation of pale, slightly granular
cytoplasmic materials were observed throughout the central nervous system. Dysmyelination
or demyelination and gemistocytic astrocytosis were observed in the white matter.
Ultrastructually, membranous cytoplasmic bodies were detected in the lysosomes of neurons.
However, genetic analysis did not identify the c.1448G>C mutation, which is the single
known mutation of feline GM1 gangliosidosis, suggesting that the cat was affected with a
new variant of the feline disease. 相似文献
18.
Measurements were carried out to survey the quantity of above- and below-ground biomass and its distribution of five Japanese
black pines (Pinus thunbergii Parl.) growing on a sandy soil. The roots, divided into diameter groups, were surveyed using two methods—soil coring and
excavation. Average dry weight of total biomass of the trees was 176,185 g. Roots represented 13.2%, below-ground stump 6.5%,
stem 70.4% and branches with needles 9.9% of total biomass. Roots made up about two thirds and stump one third of below-ground
biomass. Total length of below-ground biomass (except roots with diameter < 0.1 cm) was 479.1 m/tree. Roots with diameter
of 0.1–0.2 cm represented only 0.7% of below-ground biomass, however as much as 49.9% of their total length. Roots with diameter
over 10.0 cm constituted as much as 21.6% of below-ground biomass, however were only 0.3% of its total length. Root systems
had well developed tap roots to maximal depth of 231 cm. The results indicated that mass and length of roots with diameter
0.5–2.0 cm had a close correlation with branch mass. Mass and length of roots with diameter 2.0–10.0 cm closely correlated
to stem mass. Stem mass, root mass and root length closely correlated to DBH. A rather low correlation was found between DBH
and mass of branches and below-ground stump. DBH was a suitable variable for predicting total biomass. 相似文献
19.
Shiro Itoi Noriyuki Takai Satomi Naya Keitaro Dairiki Akira Yamada Seiji Akimoto Kiyoshi Yoshihara Haruo Sugita 《Fisheries Science》2008,74(3):503-510
ABSTRACT: Gnomefish Scombrops boops and Scombrops gilberti are commercially important fishes in Japan, but these species are often confused in the markets because of their morphological similarity. To identify these two species, we performed nucleotide sequencing and restriction fragment length polymorphism (RFLP) analysis on 16S ribosomal RNA (rRNA) gene and the control region in mitochondrial DNA. Five and 12 nucleotide substitutions were observed between species in the 777-bp 16S rRNA gene and 471-bp control region, respectively. Diagnostic restriction sites for discriminating between S. boops and S. gilberti were found in the 16S rRNA gene, but not in the control region. Polymerase chain reaction (PCR)–RFLP analysis using two enzymes, Eco NI and Mva I, clearly discriminated between S. boops and S. gilberti identified by meristic characters. The PCR–RFLP analysis identified most of the 168 Scombrops young caught in the coastal waters of the Izu and Miura peninsulas as S. boops , suggesting that S. gilberti juveniles are rare in this area. 相似文献
20.
Itaru Shioya Koji Inoue Akihisa Abe Akira Takeshita Takahiro Yamaguchi 《Fisheries Science》2011,77(5):883-889
The meat quality of farmed yellowtail Seriola quinqueradiata fed on extruded pellets (EP) containing 0.5% (v/v) red pepper (experimental group) was compared with yellowtail of the same
age fed on EP (control group). In 1-year-old yellowtail, the crude lipid content of the dorsal muscle of the experimental
group tended to be lower than that of the control group. In contrast, there was no difference in the lipid content of the
dorsal muscle between the control group and the experimental group in 2-year-old yellowtail. The muscle texture of the experimental
group was significantly firmer than that of the control group, with the effect of red pepper unrelated to fish age and lipid
content. Color change of red muscle of the experimental group was significantly lower than that of the control group, and
the content of thiobarbituric acid-reactive substances in the red muscle was significantly lower in the experimental group
than in the control group. These results are the first to demonstrate that the inclusion of red pepper in the diet is able
to reduce the loss of muscle texture firmness and to slow down color change in red muscle of yellowtail. 相似文献