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41.
Hirasaki S Kanzaki H Fujita K Suzuki S Kobayashi K Suzuki H Saeki H 《World journal of gastroenterology : WJG》2008,14(4):638-640
Intussusception is rare in adults. We describe a 47-yearold man with ileal schwannoma that led to ileocolic intussusception. Abdominal ultrasonography, abdominal CT scan and barium enema confirmed an ileal tumor. Colonoscopy revealed a peduncular submucosal tumor (SMT) 75 mm long with an ulcerated apex at the ascending colon. The provisional diagnosis was a gastrointestinal stromal tumor of the terminal ileum. Ileocecal resection was carried out and the tumor was histologically diagnosed as schwannoma. Abdominal pain resolved postoperatively. This case reminds us that ileal schwannoma should be included in the differential diagnosis of intussusception caused by an SMT in the intestine. 相似文献
42.
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
43.
Ryosuke Ando Aya Tomita Kohei Watanabe Hiroshi Akima 《Clinical physiology and functional imaging》2018,38(4):566-572
We compared vasti muscle electromyograms for two knee joint angles during fatiguing tetanic contractions. Tetanic contraction of the knee extensors was evoked for 70 s by electrical stimulation of the femoral nerve at knee joint angles of 60° (extended, with 0° indicating full extension) and 110° (flexed) in eight healthy men. Surface electromyography was recorded from the vastus intermedius (VI), vastus lateralis (VL) and vastus medialis (VM) muscles. Knee extension force and M‐wave amplitudes and durations were calculated every 7 s, which were normalized by the initial value. Normalized knee extension force was decreased at the flexed knee joint angle compared with that of the extended knee joint angle (P<0·05). Decreased normalized M‐wave amplitude and increased normalized M‐wave duration of the VI were greater at the flexed knee joint angle than the extended knee joint angle (P<0·05), whereas those for the VL and VM were similar (P>0·05). These results suggest that peripheral fatigue profiles of the VI might be greater at the flexed than the extended knee joint angles, but that of VL and VM might be similar in the tested range of knee joint angles (i.e. 60°–110°) during continuous tetanic contraction induced by electrical stimulation. Therefore, greater reduction of knee extension force at the flexed knee joint angle than the extended knee joint angle may reflect fatigue development of the VI more than other quadriceps femoris components. 相似文献
44.
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
45.
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46.
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
47.
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
48.
Junya Sato Hiroyuki Matsubayashi Hirotoshi Ishiwatari Tatsunori Satoh Junichi Kaneko Kazuma Ishikawa Masao Yoshida Kohei Takizawa Yohei Yabuuchi Yoshihiro Kishida Kenichiro Imai Kinichi Hotta Katsuhiko Uesaka Keiko Sasaki Hiroyuki Ono 《Internal medicine (Tokyo, Japan)》2021,60(5):739
We herein report a unique form of autoimmune pancreatitis (AIP) spreading along the main pancreatic duct (MPD). A 70-year-old man was referred for a small lesion at the pancreatic neck, accompanying an adjacent cyst and dilated upstream MPD. Four years earlier, health checkup images had shown a pancreatic cyst but no mass lesion. Endoscopic ultrasonography showed a contrast-enhanced, tumorous lesion, mainly occupying the MPD. With a preoperative diagnosis of ductal neoplasms mainly spreading in the MPD, Whipple''s resection was performed. The resected specimens showed MPD periductitis with IgG4-related pathology, indicating type 1 AIP. Clinicians should practice caution concerning the various AIP forms. 相似文献
49.
Kohei Ashikaga Haruki Itoh Tomoko Maeda Hidetaka Itoh Yuri Ichikawa Shiori Tanaka Ryuichi Ajisaka Akira Koike Shigeru Makita Kazuto Omiya Yuko Kato Hitoshi Adachi Masatoshi Nagayama Akihiko Tajima Naomi Harada Yoshihiro J Akashi 《Journal of cardiology》2021,77(1):57-64
BackgroundThe current understanding of ventilator efficiency variables during ramp exercise testing in the normal Japanese population is insufficient, and the responses of tidal volume (VT) and minute ventilation (V?E) to the ramp exercise test in the normal Japanese population are not known.MethodsA total of 529 healthy Japanese subjects aged 20–78 years underwent cardiopulmonary exercise testing using a cycle ergometer with ramp protocols. VT and V?E at rest, at anaerobic threshold, and at peak exercise were determined. The slope of V?E versus carbon dioxide (V?CO2) (V?E vs. V?CO2 slope), minimum V?E/V?CO2, and oxygen uptake efficiency slope (OUES) were determined.ResultsFor males and females in their 20 s, peak VT (VTpeak) was 2192 ± 376 and 1509 ± 260 mL (p < 0.001), peak V?E (V?Epeak) was 80.6 ± 18.7 and 57.7 ± 13.9 L/min (sex differences p < 0.001), the V?E vs. V?CO2 slope was 24.4 ± 3.2 and 25.7 ± 3.2 (p = 0.035), the minimum V?E/V?CO2 was 24.2 ± 2.3 and 27.0 ± 2.8 (p < 0.001), and the OUES was 2452 ± 519 and 1991 ± 315 (p < 0.001), respectively. VTpeak and V?Epeak decreased with age and increased with weight and height. The V?E vs. V?CO2 slope and minimum V?E/V?CO2 increased with age, while conversely, the OUES decreased with age.ConclusionsWe have established the normal range of VT and V?E responses, the V?E vs. V?CO2 slope, the minimum V?E/V?CO2, and the OUES for a healthy Japanese population. Some of these parameters were influenced by weight, height, sex, and age. These results provide useful reference values for interpreting the results of cardiopulmonary exercise testing in cardiac patients. 相似文献
50.
Yasuharu Matsunaga-Lee MD Yasuyuki Egami MD Kohei Ukita MD Akito Kawamura MD Hitoshi Nakamura MD Yutaka Matsuhiro MD Koji Yasumoto MD Masaki Tsuda MD Akihiro Tanaka MD Naotaka Okamoto MD Masamichi Yano MD PhD Ryu Shutta MD Yasushi Sakata MD PhD FACC FESC Masami Nishino MD PhD FACC FESC Jun Tanouchi MD PhD 《Journal of cardiovascular electrophysiology》2021,32(1):58-66