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51.
52.
Shiho Ohnishi Mariko Murata Shinji Oikawa Yusuke Hiraku Shosuke Kawanishi 《Free radical research》2013,47(6):469-478
Hydrazobenzene is carcinogenic to rats and mice and azobenzene is carcinogenic to rats. Hydrazobenzene is a metabolic intermediate of azobenzene. To clarify the mechanism of carcinogenesis by azobenzene and hydrazobenzene, we investigated DNA damage induced by hydrazobenzene, using 32P-5′-end-labeled DNA fragments obtained from the c-Ha-ras-1 proto-oncogene and the p53 tumor suppressor gene. Hydrazobenzene caused DNA damage in the presence of Cu(II). Piperidine treatment enhanced the DNA damage greatly, suggesting that hydrazobenzene caused base modification and liberation. However, azobenzene did not cause DNA damage even in the presence of Cu(II). Hydrazobenzene plus Cu(II) caused DNA damage frequently at thymine residues. Catalase and a Cu(I)-specific chelator inhibited Cu(II)-mediated DNA damage by hydrazobenzene. Typical ·OH scavengers did not inhibit the DNA damage. The main active species is probably a metal oxygen complex, such as Cu(I)-OOH. Formation of 8-oxo-7, 8-dihydro-2′-deoxyguanosine was increased by hydrazobenzene in the presence of Cu(II). Oxygen consumption and UV-Visible spectroscopic measurements have shown that hydrazobenzene is autoxidized to azobenzene with H2O2 formation. It is considered that the metal-mediated DNA damage by hydrazobenzene through H2O2 generation may be relevant for the expression of carcinogenicity of azobenzene and hydrazobenzene. 相似文献
53.
Yasuhito Hamaguchi Manabu Fujimoto Takashi Matsushita Kenzo Kaji Kazuhiro Komura Minoru Hasegawa Masanari Kodera Eiji Muroi Keita Fujikawa Mariko Seishima Hidehiro Yamada Ryo Yamada Shinichi Sato Kazuhiko Takehara Masataka Kuwana 《PloS one》2013,8(4)
Objective
To identify similarities and differences in the clinical features of adult Japanese patients with individual anti-aminoacyl-tRNA synthetase antibodies (anti-ARS Abs).Methods
This was a retrospective analysis of 166 adult Japanese patients with anti-ARS Abs detected by immunoprecipitation assays. These patients had visited Kanazawa University Hospital or collaborating medical centers from 2003 to 2009.Results
Anti-ARS Ab specificity included anti-Jo-1 (36%), anti-EJ (23%), anti-PL-7 (18%), anti-PL-12 (11%), anti-KS (8%), and anti-OJ (5%). These anti-ARS Abs were mutually exclusive, except for one serum Ab that had both anti-PL-7 and PL-12 reactivity. Myositis was closely associated with anti-Jo-1, anti-EJ, and anti-PL-7, while interstitial lung disease (ILD) was correlated with all 6 anti-ARS Abs. Dermatomyositis (DM)-specific skin manifestations (heliotrope rash and Gottron’s sign) were frequently observed in patients with anti-Jo-1, anti-EJ, anti-PL-7, and anti-PL-12. Therefore, most clinical diagnoses were polymyositis or DM for anti-Jo-1, anti-EJ, and anti-PL-7; clinically amyopathic DM or ILD for anti-PL-12; and ILD for anti-KS and anti-OJ. Patients with anti-Jo-1, anti-EJ, and anti-PL-7 developed myositis later if they had ILD alone at the time of disease onset, and most patients with anti-ARS Abs eventually developed ILD if they did not have ILD at disease onset.Conclusion
Patients with anti-ARS Abs are relatively homogeneous. However, the distribution and timing of myositis, ILD, and rashes differ among patients with individual anti-ARS Abs. Thus, identification of individual anti-ARS Abs is beneficial to define this rather homogeneous subset and to predict clinical outcomes within the “anti-synthetase syndrome.” 相似文献54.
对侧盘菌属在英国的研究概况进行了评述,研究侧重于Otidea apophysata和O.platyspora两个具有大型子囊孢子的种。同时,对4个错误地用于大型孢子种的名称进行了订正:O. abietina(Pseudotis属的模式种)是含糊名称(nomen ambiguum);O.cochleata也为含糊名称;O. felina是O.alutacea的同物异名,并为后者指定了选模式;将O.umbrina处理为O.bufonia的同物异名。此外,确定了Otidea violacea的分类地位。 相似文献
55.
Susumu Kudo Minoru Kawarabayashi Mariko Ikeda Kazuo Tanishita 《Journal of Biorheology》2013,26(1-2):38-43
Recent studies suggest that the temporal gradient of shear stress that is generated by blood flow plays an important role in the pathology of arteriosclerosis. We focused on the temporal gradient of shear stress and measured the permeability of albumin under steady or pulsatile shear stress conditions. Porcine aortic endothelial cells were seeded on a membrane filter and subjected to steady or pulsatile shear stress (1 Hz) at 1 Pa for 48 h, and the permeability of albumin was measured over time. The permeability increased gradually under steady flow but increased acutely under pulsatile shear stress. In particular, the maximum permeability of albumin differed under these conditions. The value was 4.2 × 10?5 cm/s at 18 h under pulsatile shear stress and 2.8 × 10?5 cm/s at 48 h under steady shear stress. The permeable route of albumin was examined using isoproterenol, which decreases junctional permeability. The increase in albumin permeability with pulsatile shear stress was decreased by isoproterenol. These results suggest that the increased permeability of albumin with pulsatile shear stress was related to trafficking through paracellular junctions. Thus, pulsation may promote a mechanotransduction process that differs from that of steady shear stress, and these pulsation effects likely play an important role in the permeability of macromolecules. 相似文献
56.
Takeo Kawahara Naoe Hotta Yukiko Ozawa Seiichi Kato Keiko Kano Yukihiro Yokoyama Masato Nagino Takashi Takahashi Kiyoshi Yanagisawa 《PloS one》2013,8(12)
Elucidation of how pancreatic cancer cells give rise to distant metastasis is urgently needed in order to provide not only a better understanding of the underlying molecular mechanisms, but also to identify novel targets for greatly improved molecular diagnosis and therapeutic intervention. We employed combined proteomic technologies including mass spectrometry and isobaric tags for relative and absolute quantification peptide tagging to analyze protein profiles of surgically resected human pancreatic ductal adenocarcinoma tissues. We identified a protein, dihydropyrimidinase-like 3, as highly expressed in human pancreatic ductal adenocarcinoma tissues as well as pancreatic cancer cell lines. Characterization of the roles of dihydropyrimidinase-like 3 in relation to cancer cell adhesion and migration in vitro, and metastasis in vivo was performed using a series of functional analyses, including those employing multiple reaction monitoring proteomic analysis. Furthermore, dihydropyrimidinase-like 3 was found to interact with Ezrin, which has important roles in cell adhesion, motility, and invasion, while that interaction promoted stabilization of an adhesion complex consisting of Ezrin, c-Src, focal adhesion kinase, and Talin1. We also found that exogenous expression of dihydropyrimidinase-like 3 induced activating phosphorylation of Ezrin and c-Src, leading to up-regulation of the signaling pathway. Taken together, the present results indicate successful application of combined proteomic approaches to identify a novel key player, dihydropyrimidinase-like 3, in pancreatic ductal adenocarcinoma tumorigenesis, which may serve as an important biomarker and/or drug target to improve therapeutic strategies. 相似文献
57.
Tomoko Lee Yasuhiro Takeshima Yo Okizuka Kiyoshi Hamahira Noriko Kusunoki Hiroyuki Awano Mariko Yagi Norio Sakai Masafumi Matsuo Kazumoto Iijima 《Gene》2013
Geleophysic dysplasia (GD) is a rare disorder characterized by severe short stature, short hands and feet, limited joint mobility, skin thickening, characteristic facial features (e.g., a “happy” face), and cardiac valvular disorders that often result in an early death. The genes ADAMTSL2 (a disintegrin-like and metalloprotease with thrombospondin type 1 motif-like 2) and FBN1 (fibrillin 1) were recently identified as causative genes for GD. Here, we describe a 10-year-old Japanese female with GD who was born to non-consanguineous parents. At the age of 11 months, she was referred to our hospital because of very short stature for her age (− 4.4 standard deviations of the age-matched value) and a “happy” face with full cheeks, a shortened nose, hypertelorism, and a long and flat philtrum, characteristic of GD. Her hands and feet were small, her skin was thickened, and her joint mobility was generally limited. She had cardiac valvular disorders and history of recurrent respiratory failure. Mutation analysis revealed no abnormalities in ADAMTSL2. However, analysis of FBN1 revealed a novel heterozygous mutation (c.5161T > T/G) in exon 41, which encodes transforming growth factor-β-binding protein-like domain 5 (TB5). GD is an extremely rare disorder and, to our knowledge, only one case of GD with an FBN1 mutation has been reported in Japan. Similar to the previously reported cases of GD, the mutation in the current patient was located in the TB5 domain, which suggests that abnormalities in this domain of FBN1 are responsible for GD. 相似文献
58.
Kanako Ishihara Kumiko Nakajima Satoko Kishimoto Fumiaki Atarashi Yasukazu Muramatsu Akitoyo Hotta Satomi Ishii Yasuyuki Takeda Masanori Kikuchi Yutaka Tamura 《Microbiology and immunology》2013,57(10):684-691
To determine and compare the extent of contamination caused by antimicrobial‐resistant lactic acid bacteria (LAB) in imported and domestic natural cheeses on the Japanese market, LAB were isolated using deMan, Rogosa and Sharpe (MRS) agar and MRS agar supplemented with six antimicrobials. From 38 imported and 24 Japanese cheeses, 409 LAB isolates were obtained and their antimicrobial resistance was tested. The percentage of LAB resistant to dihydrostreptomycin, erythromycin, and/or oxytetracycline isolated from imported cheeses (42.1%) was significantly higher than that of LAB resistant to dihydrostreptomycin or oxytetracycline from cheeses produced in Japan (16.7%; P = 0.04). Antimicrobial resistance genes were detected in Enterococcus faecalis (tetL, tetM, and ermB; tetL and ermB; tetM) E. faecium (tetM), Lactococcus lactis (tetS), Lactobacillus (Lb.), casei/paracasei (tetM or tetW), and Lb. rhamnosus (ermB) isolated from seven imported cheeses. Moreover, these E. faecalis isolates were able to transfer antimicrobial resistance gene(s). Although antimicrobial resistance genes were not detected in any LAB isolates from Japanese cheeses, Lb. casei/paracasei and Lb. coryniformis isolates from a Japanese farm‐made cheese were resistant to oxytetracycline (minimal inhibitory concentration [MIC], 32 µg/mL). Leuconostoc isolates from three Japanese farm‐made cheeses were also resistant to dihydrostreptomycin (MIC, 32 to > 512 µg/mL). In conclusion, the present study demonstrated contamination with antimicrobial‐resistant LAB in imported and Japanese farm‐made cheeses on the Japanese market, but not in Japanese commercial cheeses. 相似文献
59.
Michio Nakamura Nadia Corp Mariko Fujimoto Shiho Fujita Shunkichi Hanamura Hitoshige Hayaki Kazuhiko Hosaka Michael A. Huffman Agumi Inaba Eiji Inoue Noriko Itoh Nobuyuki Kutsukake Mieko Kiyono-Fuse Takanori Kooriyama Linda F. Marchant Akiko Matsumoto-Oda Takahisa Matsusaka William C. McGrew John C. Mitani Hitonaru Nishie Koshi Norikoshi Tetsuya Sakamaki Masaki Shimada Linda A. Turner James V. Wakibara Koichiro Zamma 《Primates; journal of primatology》2013,54(2):171-182
We have analyzed the ranging patterns of the Mimikire group (M group) of chimpanzees in the Mahale Mountains National Park, Tanzania. During 16 years, the chimpanzees moved over a total area of 25.2 or 27.4 km2, as estimated by the grid-cell or minimum convex polygon (MCP) methods, respectively. Annually, the M group used an average of 18.4 km2, or approximately 70 %, of the total home-range area. The chimpanzees had used 80 % of their total home range after 5 years and 95 % after 11 years. M group chimpanzees were observed more than half of the time in areas that composed only 15 % of their total home range. Thus, they typically moved over limited areas, visiting other parts of their range only occasionally. On average, the chimpanzees used 7.6 km2 (in MCP) per month. Mean monthly range size was smallest at the end of the rainy season and largest at the end of the dry season, but there was much variability from year to year. The chimpanzees used many of the same areas every year when Saba comorensis fruits were abundant between August and January. In contrast, the chimpanzees used several different areas of their range in June. Here range overlap between years was relatively small. Over the 16 years of the study we found that the M group reduced their use of the northern part of their range and increased their frequency of visits to the eastern mountainous side of their home range. Changes in home-range size correlated positively with the number of adult females but not with the number of adult males. This finding does not support a prediction of the male-defended territory model proposed for some East African chimpanzee unit-groups. 相似文献
60.
Kensuke Miyamoto Mariko Oka Eiji Uheda Junichi Ueda 《Acta Physiologiae Plantarum》2013,35(9):2675-2683
Changes in cell wall polysaccharides in oat (Avena sativa L.) leaf segments during senescence promoted by methyl jasmonate (JA-Me) were studied. During the incubation with water at 25 °C in the dark, the loss of chlorophyll of the segments excised from the primary leaves of 8-day-old green seedlings was found dramatically just after leaf excision, and leaf color completely turned to yellow after the 3- to 4-day incubation in the dark. Application of 10 µM JA-Me substantially promoted the loss of chlorophyll corresponding with the chloroplast degradation. Cell wall polysaccharides in oat leaf segments mainly consisted of hemicellulosic and cellulosic ones. During the process of leaf senescence, the amount of hemicellulosic I and II, and cellulosic polysaccharides decreased, but little in pectic polysaccharides. JA-Me significantly enhanced the decrease in cellulosic polysaccharides, but little in hemicellulosic ones. Arabinose, xylose and glucose were identified as main constituents of neutral sugars of hemicellulosic polysaccharides. The neutral sugar compositions of hemicellulosic polysaccharides changed little during leaf senescence both in the presence or absence of JA-Me. These facts suggest that JA-Me affects sugar metabolism relating to cellulosic polysaccharides during leaf senescence. 相似文献