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141.
The flagellin genes (fliC) of Clostridium chauvoei, Clostridium haemolyticum, Clostridium novyi types A and B, and Clostridium septicum were analysed by PCR amplification and DNA sequencing. The five Clostridium species have at least two copies of the flagellin gene (fliC) arranged in tandem on the chromosome. The deduced N- and C-terminal aminoacid sequences of the flagellin proteins (FliCs) of these clostridia are well conserved but their central region aminoacid sequences are not. Phylogenic analysis based on the N-terminal aminoacid sequence of the FliC protein revealed that these clostridia, which belong to Clostridium 16S rDNA phylogenic cluster I (), are more closely related to Bacillus subtilis than to Clostridium difficile, which belongs to the cluster XI. Moreover, a multiplex polymerase reaction (PCR) system based on the fliC sequence was developed to rapidly identify C. chauvoei, C. haemolyticum, C. novyi types A and B, and C. septicum. PCR of each Clostridium amplified a species-specific band. The multiplex PCR system may be useful for rapid identification of pathogenic clostridia. 相似文献
142.
Kobayashi S Sato R Aoki T Omoe K Inanami O Hankanga C Yamada Y Tomizawa N Yasuda J Sasaki J 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(5):429-435
Feline immunodeficiency virus (FIV) infection is characterized by chronic overactivation of immune and inflammatory system, resulting in anergic state and dysfunction of immune cells. Lactoferrin (LF), a glycoprotein present in exocrine secretions and neutrophils, plays an important role in host defense system. Our previous study showed that oral administration of bovine LF (bLF) suppressed oral inflammation, improved the clinical symptoms and decreased serum gamma-globulin as a marker of inflammation in FIV-infected cats with intractable stomatitis. The anti-inflammatory effect was partly involved in regulation of neutrophil function by bLF. In this study, to clarify the relationship between anti-inflammatory effects of bLF and peripheral blood mononuclear cells (PBMC), we examined the effect of bLF on proliferation, cell cycle progression and cytokine expression in mitogen-activated PBMC. MTT [3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyl tetrazolium bromide] assay showed that bLF inhibited the concanavalin A (ConA)-induced cell proliferation in FIV-infected cats with the asymptomatic carrier and AIDS-related complex (ARC) phase. Bovine LF restored ConA-induced cell cycle progression and resulted in suppression of the induced apoptosis in feline PBMC. Real-time RT-PCR showed that bLF suppressed ConA-induced expression of interferon-gamma and interleukin-2 in cells of the ARC group regardless of the time of its addition to the medium. These results suggest the hypothesis that therapy with bLF may have the potential to improve and protect functions of overactivated lymphocytes by modulating the cell proliferation, cell cycle and cytokines expression in cats in terminal stage of FIV infection. 相似文献
143.
Thongphakdee A Kobayashi S Imai K Inaba Y Tasai M Tagami T Nirasawa K Nagai T Saito N Techakumphu M Takeda K 《The Journal of reproduction and development》2008,54(2):142-147
This study was conducted to investigate the developmental capacity of domestic cat-bovine reconstructed embryos via interspecies somatic cell nuclear transfer (iSCNT) and to observe the mitochondrial DNA (mtDNA) content of the iSCNT embryos. The iSCNT embryos were generated using mixed-breed domestic cat fibroblasts as donor cells and enucleated bovine oocytes as the recipient cytoplasm. When the developmental capacities of iSCNT embryos and parthenogenic bovine embryos were compared, there was no difference (P>0.05) in the rates of cleavage and development to the 8-cell stage (86.6 vs. 84.0% and 32.2 vs. 36.2%, respectively). However, in contrast to development of parthenogenic embryos to the morula and blastocyst stages, no iSCNT embryos (0/202) developed beyond the 8-cell stage. For mtDNA analysis, iSCNT embryos at the 1-cell, 2-cell, 4-cell and 8-cell stages were randomly selected. Both cat and bovine mtDNA quantification analysis were performed using quantitative PCR. The levels of both cat and bovine mtDNA in cat-bovine iSCNT embryos varied at each stage of development. The cat mtDNA concentration in the iSCNT embryos was stable from the 1-cell to 8-cell stages. The bovine mtDNA in the iSCNT embryos at the 8-cell stage was significantly lower than that at the 4-cell stage (P<0.05). No difference in the proportions of cat mtDNA in the iSCNT embryos was found in any of the observed developmental stages (1- through 8-cell stages). In conclusion, bovine cytoplasm supports domestic cat nucleus development through the 8-cell stage. The mtDNA genotype of domestic cat-bovine iSCNT embryos illustrates persistence of heteroplasmy, and the reduction in mtDNA content might reflect a developmental block at the 8-cell stage. 相似文献
144.
We previously developed insertion-deletion (InDel) markers that distinguish three genotypes (two homozygous and one heterozygous) of diverse citrus cultivars. These InDel markers were codominant and could be clearly detected by using simple agarose gel electrophoresis. We sought to establish a method for cultivar identification using these 28 InDel markers to genotype 31 citrus cultivars. The results revealed that a minimum of 6 markers were required to identify individuals using the three-genotype classification method. Furthermore, we found that a simple method for distinguishing between two genotypes (homozygous and heterozygous) could be used to identify individuals using a minimum of 7 markers. Our findings provide a basis for the development of simple and rapid citrus cultivar identification methods. 相似文献
145.
Fukuda Toshiyuki Sato Yuichi Takiguchi Mako Yamamoto Takahiro Murasawa Hiroyasu Pawlak Akiko Kobayashi Hiroyuki Tamano Haruna Takeda Atsushi 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(2):279-282
Plant Foods for Human Nutrition - Amyloid β (Aβ) peptides produced from the amyloid precursor protein, a transmembrane protein, are neurotoxic and blocking the neurotoxicity may lead to... 相似文献
146.
Takao Morita Kaoru Banshoya Takahiro Tsutsumoto Yasuhide Murase 《Journal of Wood Science》1999,45(6):463-469
Continuous milling tests with diamond-coated and uncoated cemented carbide tools and polycrystalline diamond tools were carried out on air-dried and wet melapi (Shorea sp.) and western redcedar (Thuja plicata D. Don). These tools were examined for corrosive-wear characteristics of the tool-edge appearance, cutting-edge profile, edge recession, and cutting-power consumption. The tool surfaces were observed with a scanning electron microscope and were analyzed by energy-dispersive X-ray spectroscopy. Based on these examinations, the occurrence of corrosive wear while cutting wet woods was confirmed for the uncoated and polycrystalline diamond tools. In contrast, the coated tools did not exhibit corrosive wear, nor did delamitation or wear of the diamond film occur with any of the work materials. The diamond-coated tools showed high resistance not only to mechanical wear but also to corrosive wear.The results of this work were presented at the 48th annual meeting of the Japan Wood Research Society, Shizuoka, April 1998 相似文献
147.
Genetic differences between a collection of aeromonads were studied in two laboratories by analysis of randomly amplified polymorphic DNA (RAPD). A single randomly designed primer, generated reproducible profiles of genomic DNA in both laboratories for Aeromonas salmonicida subspecies salmonicida, although the profiles differed between laboratories. Analysis of atypical strains of A. salmonicida and isolates of the A. hydrophila group produced scattered profiles in both laboratories. The uniform fingerprints produced for A. salmonicida subspecies salmonicida indicate genomic homogeneity. The scattered RAPD profiles of the motile aeromonads demonstrate the genomic diversity of this group. A group of unspeciated motile aeromonads gave uniform fingerprints, suggesting the possibility of a genomically homogeneous species. Although the RAPD technique is susceptible to the effects of minor technical variations, this study has demonstrated that where there is DNA similarity, it can be recognized, and where there is diversity, differentiation can be made. RAPD promises to be useful in epidemiological studies for rapid identification of bacteria where a source of reference DNA is available and may be useful in preliminary investigations of relatedness within groups. 相似文献
148.
149.
Hidehiro Kondo Takami Morita Maki Ikeda Chihiro Kurosaka Aiko Shitara Yuka Honda Reiko Nozaki Takashi Aoki Ikuo Hirono 《Fisheries Science》2010,76(1):161-165
Expressed sequence tag (EST) analyses were performed with the aim of identifying enzyme genes in the liver of the Bleeker’s squid Loligo bleekeri. Of the 768 ESTs identified and sequenced, 669 were grouped into 324 clusters. Of these clusters, 123 comprising 245 ESTs were found to be homologous to genes reported to date. Among these, 43 clusters were annotated as enzymes according to the Enzyme Commission (EC) numbering system. Two EC groups, oxidoreductases and hydrolases, possessed a large number of ESTs. A cluster homologous to the glutathione peroxidase, an enzyme in the oxidoreductase group, contained 16 ESTs, which accounted for 2.4% of the total ESTs sequenced. There are three serine proteases, three cathepsins, two triacylgricerol lipases, and two chitinases among the clusters homologous to the enzymes in the hydrolase group. Since the squid liver functions in the digestive process, these enzymes would be involved in food digestion. Our data provide information on the various types of enzymes expressed in the squid liver and may provide a useful basis for further characterization of these enzymes. 相似文献
150.
Hiroki Yasuma Ryo Nakagawa Takashi Yamakawa Kazushi Miyashita Ichiro Aoki 《Fisheries Science》2009,75(3):545-552
Sound-speed and density contrasts (h and g, respectively), important acoustic material properties, of Japanese sandeel Ammodytes personatus were measured to estimate theoretical target strength (TS). The measured sound-speed contrast of adult fish varied between
1.016 and 1.023 (mean 1.020), and showed temperature dependence. The measured density contrast differed significantly between
juvenile and adult. The density contrast of juvenile varied between 1.017 and 1.024 (1.021), and that of adult varied between
1.026 and 1.038 (1.032). Using these results, TS at 38 and 120 kHz in the fishing season were estimated by an empirical sound
scattering model. TS of an individual fish varied significantly with change of tilt angle. TS of near-dorsal aspect (TSmax) and tilt-averaged TS (TSave) differed by up to 7 dB. At both frequencies, two different TSave−length relationships (TSave = a log L + b) were obtained for adult and juvenile. The coefficients of log L of adult were close to 20, suggesting that backscattering strength was proportional to square of body length. These values
were larger in juvenile (34.0 at 120 kHz, 56.5 at 38 kHz), suggesting that backscattering strength varied drastically with
the cube or fifth power of body length. 相似文献