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1.
2.
Previous studies of monocytes isolated from peripheral blood have suggested that the lung sequesters these cells and has an important role in monocyte kinetics. However, the lung also provides the first capillary bed encountered by these cells after intravenous injection. A major criticism of the previous reports is that the behavior of monocytes in the lung may be altered as a result of the isolation procedure. The present study addresses this question by comparing the distribution of isolated monocytes (87% pure) in various organs 10 min after they were injected into either the central venous or the arterial circulation. The data show that the extraction of monocytes on the first passage through the lung after intravenous injection was 86.5 +/- 1.5%. After the monocytes had circulated for 10 min, the lungs contained 35.5 +/- 2.5% of the cells after intravenous injection and 29.7 +/- 2.2% after intra-arterial injection (P greater than 0.05). The lung-to-blood recovery ratio after either intravenous or intra-arterial injection showed that the lung contained a marginating pool of monocytes that was five to seven times the size of the circulating pool. The retention of monocytes in a region of the lung was proportional to the regional erythrocyte transit time. The half-life of the radiolabeled monocytes in the circulation was approximately 25 h. We conclude that the lung contains a marginating pool of monocytes and speculate that they concentrate there in preparation for migration into the interstitium and air space of the lung. 相似文献
3.
Yoshihisa Iwamoto Yusaku Suzuki Akinobu Kurita Yoko Watanabe Tadayori Shimizu Hirohisa Ohgami Yasutake Yanagihara 《Microbiology and immunology》1995,39(11):831-837
A new species, Vibrio trachuri sp. nov., was isolated from the cultured Japanese horse mackerel (Trachurus japonicus). These Vibrio were Gram negative, motile rods and formed yellow colonies on BTB teepol and TCBS plate, turned TSI medium to yellow and was sensitive to 150 μM O/129 (2,4-diamino-6,7-diisopropyl pteridine phosphate) like Listonella anguillarum which has been described as Vibrio anguillarum. However, the results of VP test and decarboxylation of lysine or dihydrolation of arginine suggested that these Vibrio are rather closely related to V. parahaemolyticus. DNA similarity determined by the microplate hybridization technique revealed that these Vibrio are genetically quite distant from Listonella anguillarum or V. parahaemolyticus and rather close to V. harveyi, although there was no Vibrio species which had more than 70% similarity value. From these results we propose to nominate Vibrio trachuri sp. nov. for this new Vibrio species. 相似文献
4.
Kiyoshi Ohkawa Takashi Hatano Naoko Takizawa Kazue Shinmoto Kyosuke Yamada Makoto Matsuda Koji Takada Yutaka Tsukada 《In vitro cellular & developmental biology. Animal》1992,28(6):449-454
Summary A human yolk sac tumor cell line, TG1, which was established from a testicular yolk sac tumor, was found to replicate continuously
in a chemically defined medium supplemented with Na2SeO3 (ISRPMI). TG1 produced several plasma proteins and growth factors: albumin, alpha-fetoprotein (AFP), ferritin, carcinoembryonic
antigen, beta-2-microglobulin, polyamine, neuron specific enolase, tissue polypeptide antigen, transferrin (Tf), epidermal
growth factor, and platelet derived growth factor. By analysis of lectin (LcHA)-affinity electrophoresis, to examine the microheterogeneity
of carbohydrate chains of synthetic glycoproteins, TG1 cells cultured with ISRPMI produced only LcHA reactive Tf and AFP based
on core fucose attached to asparagine-linkedN-acetylglucosamine residues instead of LcHA-nonreactive Tf and AFP produced by TG1 cells cultured with fetal bovine serum
(FBS)-containing medium.α1-6 Fucosyltransferase activity was significantly greater in the TG1 cells cultured with ISRPMI (39.9±1.5 pmol · h−1 · mg−1 protein) than cultured with FBS-containing media (18.2±1.2 pmol · h−1 · mg−1 protein). These results have indicated that the selective increase ofα1-6 fucosyltransferase occurred when the cells were cultured with the FBS-free synthetic media. 相似文献
5.
Toshio Nakatani Kazue Ozawa Motokazu Asano Minoru Ukikusa Yasuo Kamiyama Takayoshi Tobe 《Life sciences》1981,28(3):257-264
The changes in the energy substrate utilized by the remnant liver were studied in relation to the changes in the cellular energy status of 25 and 70% hepatectomized rabbits. In 25% hepatectomized rabbits, the energy charge level of the remnant liver remained unchanged, the energy substrate of which was predominantly glucose, rather than fatty acid. In contrast, in 70% hepatectomized rabbits, the energy production by the mitochondria was mainly dependent upon fatty acid oxidation at the early period after hepatectomy when the energy charge level decreased remarkably, and then upon glucose oxidation, concomitant with the restoration of the energy charge. It is suggested that the changes in the energy substrate utilized are closely related to those in the energy charge level and the mitochondrial phosphorylative activity of the remnant liver following hepatectomy. 相似文献
6.
Abstract The substantial photosubstitution of 5-fluoro-1,3-dimethyluracil with substituted benzenes is first achieved by the addition of trifluoroacetic acid to the reaction mixture. The presence of protons is essential for the formation of 5-aryl-1,3-dimethyluracils. 相似文献
7.
Herbert C. Lee Piyush Kumar Leonard I. Wiebe Robert McDonald John R. Mercer Kazue Ohkura 《Nucleosides, nucleotides & nucleic acids》2013,32(9):1995-2016
Abstract The stereospecific synthesis of 1-(5-deoxy-5-iodo-α-D-arabino-furanosyl)-2-aminoimidazole (iodoaminoimidazole arabinoside: IAIA, 2) is described. The reaction of the protected sugar bromide (8) and trifluoroacetamidoimidazole (10B) gave the coupled product (11B), which gave the free nucleoside (4) on deblocking. It was identical with AIA obtained by reduction of AZA (azomycin arabinoside), whose anomeric configuration was found to be a by the X-ray crystallography. 相似文献
8.
Masashi Kato Mayuko Y. Kumasaka Shoko Ohnuma Akio Furuta Yoko Kato Hossain U. Shekhar Michiyo Kojima Yasuko Koike Nguyen Dinh Thang Nobutaka Ohgami Thuy Bich Ly Xiaofang Jia Husna Yetti Hisao Naito Gaku Ichihara Ichiro Yajima 《PloS one》2013,8(6)
Health risk for well drinking water is a worldwide problem. Our recent studies showed increased toxicity by exposure to barium alone (≤700 µg/L) and coexposure to barium (137 µg/L) and arsenic (225 µg/L). The present edition of WHO health-based guidelines for drinking water revised in 2011 has maintained the values of arsenic (10 µg/L) and barium (700 µg/L), but not elements such as manganese, iron and zinc. Nevertheless, there have been very few studies on barium in drinking water and human samples. This study showed significant correlations between levels of arsenic and barium, but not its homologous elements (magnesium, calcium and strontium), in urine, toenail and hair samples obtained from residents of Jessore, Bangladesh. Significant correlation between levels of arsenic and barium in well drinking water and levels in human urine, toenail and hair samples were also observed. Based on these results, a high-performance and low-cost adsorbent composed of a hydrotalcite-like compound for barium and arsenic was developed. The adsorbent reduced levels of barium and arsenic from well water in Bangladesh and Vietnam to <7 µg/L within 1 min. Thus, we have showed levels of arsenic and barium in humans and propose a novel remediation system. 相似文献
9.
Yui Shimizu Kazue Ohishi Rintaro Suzuki Yuko Tajima Tadasu Yamada Yuka Kakizoe Takeharu Bando Yoshihiro Fujise Hajime Taru Tsukasa Murayama Tadashi Maruyama 《Microbiology and immunology》2013,57(9):624-632
Morbillivirus infection is a severe threat to marine mammals. Mass die‐offs caused by this infection have repeatedly occurred in bottlenose dolphins (Turiops truncatus) and striped dolphins (Stenella coeruleoalba), both of which belong to the family Delphinidae, but not in other cetaceans. However, it is unknown whether sensitivity to the virus varies among cetacean species. The signaling lymphocyte activation molecule (SLAM) is a receptor on host cells that allows morbillivirus invasion and propagation. Its immunoguloblin variable domain‐like (V) region provides an interface for the virus hemagglutinin (H) protein. In this study, variations in the amino acid residues of the V region of 26 cetacean species, covering almost all cetacean genera, were examined. Three‐dimensional (3D) models of them were generated in a homology model using the crystal structure of the marmoset SLAM and measles virus H protein complex as a template. The 3D models showed 32 amino acid residues on the interface that possibly bind the morbillivirus. Among the cetacean species studied, variations were found at six of the residues. Bottlenose and striped dolphins have substitutions at five positions (E68G, I74V, R90H, V126I, and Q130H) compared with those of baleen whales. Three residues (at positions 68, 90 and 130) were found to alternate electric charges, possibly causing changes in affinity for the virus. This study shows a new approach based on receptor structure for assessing potential vulnerability to viral infection. This method may be useful for assessing the risk of morbillivirus infection in wildlife. 相似文献
10.
Isamu Shiio Shin-ichi Sugimoto Kazue Kawamura 《Bioscience, biotechnology, and biochemistry》2013,77(7):1849-1854
Azaserine-resistant mutants derived from a 5-fluorotryptophan-resistant, l-tryptophan-producing mutant of Brevibacterium flavum, accumulated 10.3 g/liter of l-tryptophan at maximum. The production increased to 11.4 g/liter when l-serine was added. In the mutant, only anthranilate synthase among enzymes of the tryptophan-specific bio synthetic pathway increased in activity to a 2-fold higher level than that in the parent strain, No. 187. Sensitivity of anthranilate synthase to the feedback inhibition was not altered by the mutation. Activity of 3-deoxy-d-arabino-heptulosonate 7-phosphate synthase, the first common enzyme for aromatic amino acid biosynthesis, also increased 2.7-fold and was less sensitive to the feedback inhibition by phenylalanine and tyrosine. Tryptophan transport activity in strain A-100 was similar as that in the parent. Azaserine inhibited anthranilate synthase activity by 50% at 0.075 mm. The inhibition was of a mixed type with respect to both the two substrates. Anthranilate synthase of strain A-100 was inhibited in a similar manner to that of the parent. 相似文献