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91.
Myocardial bridging increases the risk of coronary spasm 总被引:2,自引:0,他引:2
Teragawa H Fukuda Y Matsuda K Hirao H Higashi Y Yamagata T Oshima T Matsuura H Chayama K 《Clinical cardiology》2003,26(8):377-383
BACKGROUND: Myocardial bridging (MB) has been associated with cardiac events. Whether coronary spasm is one factor contributing to those events is unknown. HYPOTHESIS: This study investigated whether the likelihood of coronary spasm is increased in patients with MB. METHODS: A spasm-provocation test was performed by infusing acetylcholine into the left coronary artery in 114 Japanese patients with chest pain. The test result was defined as positive when the diameter of the coronary artery was reduced by > or = 50% and ST-segment changes were documented. Myocardial bridging was defined as a > 15% reduction in coronary arterial diameter during systole after intracoronary injection of nitroglycerin. RESULTS: Myocardial bridging was identified in 41 patients (36%) and was located in the mid-segment of the left anterior descending coronary artery (LAD) in all patients. Patients with MB experienced coronary spasm more frequently than patients without MB (MB+: 73%; MB-: 40%, p = 0.0006). Furthermore, among patients with a positive spasm-provocation test, coronary spasm occurred more frequently in the mid-segment of the LAD in patients with MB than in those without MB (MB+: 73%; MB-: 45%, p = 0.0259). Multivariate regression analysis demonstrated that MB was a predictor of coronary spasm (odds ratio: 3.478, p = 0.0088). CONCLUSIONS: These results suggest that MB increases the risk of coronary spasm and that coronary spasm may be the proximate etiology of cardiac events associated with MB. 相似文献
92.
Hiroshi Matsuura M.D. Masami Murai M.D. Takenori Hashimoto M.D. Takafumi Matsumoto M.D. Osamu Fukui M.D. 《The American journal of gastroenterology》1983,78(1):1-5
A rare case of systemic vasculitis with second component of complement (C2) deficiency was documented in a patient who developed colonic ulcerations, jejunal edema and dilatation, cutaneous ulcers, peripheral neuropathy, and psychosis. Colonoscopy revealed typical features of ischemic colitis and radiological examination showed ischemic changes in the jejunum and ileum. Histopathological examination of the cutaneous biopsy revealed typical necrotizing vasculitis. It is very likely that multiorgan involvement, including ischemic changes of the intestine, developed secondary to vasculitis associated with C2 deficiency. 相似文献
93.
Emiko Sekine-Suzuki Ikuo Nakanishi Kohei Imai Megumi Ueno Takashi Shimokawa Ken-ichiro Matsumoto Kiyoshi Fukuhara 《RSC advances》2018,8(19):10158
About two thirds of biological damage due to low linear energy transfer (LET) radiation, such as X-rays and the plateau region of heavy-ion beams, is known to be caused by the hydroxyl radical (˙OH), the most powerful reactive oxygen species (ROS), generated via ionisation and excitation of water molecules. Thus, compounds having an efficient scavenging activity against ROS are expected to exhibit a radioprotective activity. A planar catechin analogue, where an isopropyl fragment was introduced into the catechol ring of (+)-catechin, showed an efficient protective effect against X-ray induced apoptosis in rat thymocytes compared to (+)-catechin. The planar catechin scavenged 2,2-diphenyl-1-picrylhydrazyl radicals (DPPH˙) solubilised in water by β-cyclodextrin about 10-fold faster than (+)-catechin in phosphate buffer (0.1 M, pH 7.4) at 298 K. Furthermore, the experimental log P value of the planar catechin (1.22) is reported to be significantly larger than that of (+)-catechin (0.44). The higher radical-scavenging activity and lipophilicity of the planar catechin than those of (+)-catechin may contribute in part to the higher protective activity against X-ray-induced apoptosis in rat thymocytes.A planar catechin analogue showed a significant higher protective activity against X-ray induced apoptosis in rat thymocytes than (+)-catechin. 相似文献
94.
Yusuke Matsuya Kaori Tsutsumi Kohei Sasaki Hiroyuki Date 《Journal of radiation research》2015,56(1):90-99
We have investigated the dose rate effects on cell damage caused by photon-beam irradiation. During a relatively long dose-delivery time with a low dose rate, lesions created in cells may undergo some reactions, such as DNA repair. In order to investigate these reactions quantitatively, we adopted the microdosimetric–kinetic (MK) model and deduced a cell surviving fraction (SF) formula for continuous irradiation. This model enabled us to estimate the SF from dose and dose rate. The parameters in the MK model were determined so as to generate the SF, and we attempted to evaluate the dose rate effects on the SF. To deduce the cell-specific parameters in the SF formula, including the dose rate, we performed a split-dose experiment and a single-dose experiment with a constant dose-delivery time (10 min) (to retain the condition for equivalent behavior of cell lesions) by means of a clonogenic assay. Then, using the MK model parameters, the SFs were reproduced for a variety of dose rates (1.0, 0.31, 0.18, 0.025 and 0.0031 Gy/min) and were compared with reported experimental data. The SF curves predicted by the MK model agreed well with the experimental data, suggesting that the dose rate effects appear in the kinetics of cell lesions during the dose-delivery time. From fitting the analysis of the model formula to the experimental data, it was shown that the MK model could illustrate the characteristics of log-SF in a rectilinear form at a high dose range with a relatively low dose rate. 相似文献
95.
Opioid systems mainly regulate physiological functions such as pain, emotional tone and reward circuitry in neural tissues (brain and spinal cord). These systems are also found in extraneural tissues (ganglia, gut, spleen, stomach, lung, pancreas, liver, heart, blood and blood vessels), and recent studies have elucidated their roles in various organs. The current review focuses on the roles of opioid systems in blood vessels, especially angiogenesis, during development and tumour malignancy. The balance between endogenous activators and inhibitors of angiogenesis delicately maintains a normally quiescent vasculature to sustain homeostasis. Disturbance of this balance causes pathogenic angiogenesis and, especially in tumours, several activators such as VEGF are highly expressed in the tumour microenvironment and strongly induce tumour angiogenesis, the so-called angiogenic switch. Recently, we demonstrated that κ opioid receptor agonists function as anti-angiogenic factors, which impede the angiogenic switch, in vascular development and tumour angiogenesis by inhibiting the expression of receptors for VEGF. In clinical medicine, angiogenesis inhibitors that target VEGF signalling such as bevacizumab are used as anti-cancer drugs. Although therapies that inhibit tumour angiogenesis have been highly successful for tumour therapy, most patients eventually develop resistance to this anti-angiogenic therapy. Thus, we must identify novel targets for anti-angiogenic agents to sustain inhibition of angiogenesis for tumour therapy. The regulation of responses to κ opioid receptor ligands could be useful for controlling vascular formation under physiological conditions and in cancers, and thus could offer therapeutic benefits beyond the relief of pain.
LINKED ARTICLES
This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2 相似文献96.
Masanori Kitamura Suguru Sasaki Riho Nishikawa Kohei Yamada Munetaka Kunishima 《RSC advances》2018,8(40):22482
In this paper, we discuss the synthesis of imido-substituted chlorotriazines and demonstrate their use in dehydrative condensation reactions. Chemoselective amide-forming reactions of amino alcohols using succinimido-substituted chlorotriazine (2A) proceeded smoothly. Occasionally, nonselectivity was problematic during the synthesis of hydroxy-substituted amides. Moreover, it was noteworthy that this method was applicable to hydroxy-substituted carboxylic acids that could have formed a lactone or an ester during the carboxylic acid activation step. The imido-substituted chlorotriazine (2A) was superior to the amido-substituted chlorotriazine and 2-chloro-4,6-dimethoxy-1,3,5-triazine (CDMT) in terms of reaction rates and yields.In this paper, we discuss the synthesis of imido-substituted chlorotriazines and demonstrate their use in dehydrative condensation reactions. 相似文献
97.
Asaoka Kohei Watanabe Yuki Itoh Kazuhiro Hosono Naoko Hirota Tomoya Ikawa Masamichi Yamaguchi Tomohisa Hatta Satomi Imamura Yoshiaki Nishino Ichizo Yamauchi Takahiro Iwasaki Hiromichi 《Clinical rheumatology》2021,40(6):2477-2483
Clinical Rheumatology - Eosinophilic fasciitis (EF) is a rare connective tissue disease that causes inflammation and fibrosis of the fascia, inducing pain and motor dysfunction. Characteristic skin... 相似文献
98.
Shinzaki Shinichiro Matsuoka Katsuyoshi Tanaka Hiroki Takeshima Fuminao Kato Shingo Torisu Takehiro Ohta Yuki Watanabe Kenji Nakamura Shiro Yoshimura Naoki Kobayashi Taku Shiotani Akiko Hirai Fumihito Hiraoka Sakiko Watanabe Mamoru Matsuura Minoru Nishimoto Shohei Mizuno Shinta Iijima Hideki Takehara Tetsuo Naka Tetsuji Kanai Takanori Matsumoto Takayuki 《Journal of gastroenterology》2021,56(6):560-569
Journal of Gastroenterology - This multicenter prospective study (UMIN000019958) aimed to evaluate the usefulness of serum leucin-rich alpha-2 glycoprotein (LRG) levels in monitoring disease... 相似文献
99.
Matsumoto Kazuhisa Tobiume Takeshi Matsuura Tomomi Ise Takayuki Kusunose Kenya Yamaguchi Koji Yagi Shusuke Fukuda Daijyu Wakatsuki Tetsuzo Yamada Hirotsugu Soeki Takeshi Sata Masataka 《Journal of interventional cardiac electrophysiology》2022,63(2):417-424
Journal of Interventional Cardiac Electrophysiology - Previous studies examined the right atrial (RA) input site of the antegrade fast pathway (AFp) (AFpI). However, the left atrial (LA) input to... 相似文献
100.