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41.
Akihiro Hirashiki Hideo Izawa Fuji Somura Koji Obata Tomoko Kato Takao Nishizawa Akira Yamada Hiroyuki Asano Satoru Ohshima Akiko Noda Shigeo Iino Kohzo Nagata Kenji Okumura Toyoaki Murohara Mitsuhiro Yokota 《Journal of the American College of Cardiology》2006,47(7):1382-1389
OBJECTIVES: The relation between the occurrence of pacing-induced mechanical alternans and prognosis in patients with mild-to-moderate idiopathic dilated cardiomyopathy (IDCM) in sinus rhythm was investigated prospectively. The myocardial expression of genes for Ca2+-handling proteins in such patients was also examined. BACKGROUND: Mechanical alternans occurs in some patients with severe heart failure, but the relation between the occurrence of mechanical alternans and prognosis in patients with IDCM has remained unknown. METHODS: Left ventricular (LV) pressure was measured during atrial pacing, and LV endomyocardial biopsy specimens were collected in 36 IDCM patients and 8 controls. Idiopathic dilated cardiomyopathy patients were divided into two groups consisting of 22 individuals who did not develop mechanical alternans at heart rates up to 140 beats/min (group A) and of 14 individuals who did (group B). The patients were followed up for a mean of 3.7 years. RESULTS: There was no significant difference in LV ejection fraction or the plasma concentration of brain natriuretic peptide between groups A and B. The myocardial abundance of ryanodine receptor 2 messenger ribonucleic acid (mRNA) was significantly lower in groups A and B than in controls, whereas that of sarcoplasmic reticulum Ca2+-ATPase mRNA was significantly lower in group B than in group A or controls. Stepwise multivariate analysis identified pacing-induced mechanical alternans as the strongest predictor of cardiac events. Event-free survival in group A was significantly greater than that in group B. CONCLUSIONS: The occurrence of pacing-induced mechanical alternans is a potentially useful indicator of poor prognosis in patients with mild-to-moderate IDCM in sinus rhythm. 相似文献
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Naohiro Tsuyama Hajime Mizuno Atsushi Katafuchi Yu Abe Yumiko Kurosu Mitsuaki Yoshida Kenji Kamiya Akira Sakai 《Journal of radiation research》2015,56(1):46-58
Ionizing radiation (IR) induces cellular stress responses, such as signal transduction, gene expression, protein modification, and metabolite change that affect cellular behavior. We analyzed X-irradiated human Epstein-Barr virus-transformed B lymphoblastoid cells and normal fibroblasts to search for metabolites that would be suitable IR-responsive markers by Liquid Chromotography–Mass spectrometry (LC–MS). Mass spectra, as analyzed with principal component analysis, showed that the proportion of peaks with IR-induced change was relatively small compared with the influence of culture time. Dozens of peaks that had either been upregulated or downregulated by IR were extracted as candidate IR markers. The IR-changed peaks were identified by comparing mock-treated groups to 100 mGy-irradiated groups that had recovered after 10 h, and the results indicated that the metabolites involved in nucleoside synthesis increased and that some acylcarnitine levels decreased in B lymphoblastoids. Some peaks changed by as much as 20 mGy, indicating the presence of an IR-sensitive signal transduction/metabolism control mechanism in these cells. On the other hand, we could not find common IR-changed peaks in fibroblasts of different origin. These data suggest that cell phenotype-specific pathways exist, even in low-dose responses, and could determine cell behavior. 相似文献
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Lszl Szab Sari Imanishi Naohiro Kawashima Rina Hoshino Kenji Takada Daisuke Hirose Takayuki Tsukegi Kazuaki Ninomiya Kenji Takahashi 《RSC advances》2018,8(40):22729
Interfacial interactions governing the interfacial adhesion between cellulose propionate and carbon fibre surface are placed under scrutiny to pave the way towards the development of green cellulose-based carbon fibre reinforced polymers. A range of molecular entities are deposited on the surface by initially grafting aromatic structures with appropriate functions via diazonium species followed by further derivatization of these entities. Cellulose propionate was also bound covalently to the surface via a tosylated derivative invoking its facile nucleophilic displacement reaction with surface-grafted amino functions. Significant increase in interfacial shear strength was obtained for the cellulose propionate-grafted carbon fibre composite as well as for the 4-(aminomethyl)benzene-functionalized sample, in the latter case possible hydrogen bonding took place with the cellulose propionate matrix. Furthermore, the positive effect of a highly lipophilic and yet compact –CF3 substituent was also noted. In order to let the grafted structure efficiently penetrate into the matrix, steric factors, lipophilicity and potential secondary interactions should be considered. It needs to be pointed out that we provide the first synthetic strategy to covalently bind cellulose derivatives to a largely graphitic surface and as such, it has relevance to carbonaceous materials being applied in cellulose-based innovative materials in the future.Interfacial adhesion of a cellulose propionate/carbon fibre composite is tailored providing a synthetic strategy to bind cellulose derivatives to graphitic surfaces. 相似文献
46.
Jain Divyanu Oda Tomoaki Kawai Kenta Horikoshi Yoshimasa Matsumoto Masako Narumi Megumi Kohmura-Kobayashi Yukiko Furuta-Isomura Naomi Yaguchi Chizuko Uchida Toshiyuki Suzuki Kazunao Kanayama Naohiro Itoh Hiroaki Tamura Naoaki 《Journal of thrombosis and thrombolysis》2022,53(1):208-212
Journal of Thrombosis and Thrombolysis - Pulmonary thromboembolism (PTE) is one of the leading causes of maternal mortality. We previously reported that possible contamination of amniotic fluid... 相似文献
47.
Miyoshi Jun Ozaki Ryo Yonezawa Hiromi Mori Hideaki Kawamura Naohiro Matsuura Minoru Hisamatsu Tadakazu 《Journal of gastroenterology》2022,57(2):82-89
Journal of Gastroenterology - The development of feasible, reliable parameters and criteria for intestinal ultrasound (IUS) to estimate endoscopic remission of ulcerative colitis (UC) is a crucial... 相似文献
48.
Toshihiro Nakamura MD Kunihiko Kiuchi MD FHRS Koji Fukuzawa MD Mitsuru Takami MD Yoshiaki Watanabe MD Yu Izawa MD Hideya Suehiro MD Tomomi Akita MD Makoto Takemoto MD Jun Sakai MD Atsusuke Yatomi MD Yusuke Sonoda MD Hiroyuki Takahara MD Kazutaka Nakasone MD Kyoko Yamamoto MD Noriyuki Negi RT Atsushi Kono MD Takashi Ashihara MD PhD Ken-ichi Hirata MD PhD 《Journal of cardiovascular electrophysiology》2021,32(4):1005-1013
49.
Suga N Takada H Nomura A Ohga S Ishii E Ihara K Ohshima K Hara T 《British journal of haematology》2002,116(2):346-349
The perforin gene was analysed in 15 Japanese patients with primary haemophagocytic lymphohistiocytosis (HLH). Perforin gene defects were found in two out of eight patients with familial HLH (FHL), and one out of seven without affected siblings. Four novel mutations were identified. Compound heterozygous mutations (one FHL and one sporadic HLH) and only one allele mutation (one FHL) were defined. Flow cytometry revealed no perforin expression in CD8+ or CD56+ cells from a surviving patient with a mutation. The frequency of mutation was at least 20% of FHL in Japan. Flow cytometry for intracellular perforin may be useful for the screening of FHL2. 相似文献
50.