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81.
Delayed Gastric Emptying by Helicobacter pylori Lipopolysaccharide in Conscious Rats 总被引:6,自引:0,他引:6
Toshikatsu Okumura Etsuro Shoji Nobuhiko Takahashi Hirokazu Wakebe Kenichi Imagawa Mikio Kikuchi Yutaka Kohgo 《Digestive diseases and sciences》1998,43(1):90-94
The present study was carried out to investigatethe possibility that lipopolysaccharide deprived fromHelicobacter pylori may alter gastric motility. Toaddress the question, we examined the effect of H. pylori lipopolysaccharide on gastricemptying in conscious rats. Gastric emptying wasevaluated by the phenol red method. Time-course anddose-related effects of intraperitoneal administrationof H. pylori lipopolysaccharide were investigated.Intraperitoneal injection of H. pylorilipopolysaccharide significantly suppressed gastricemptying of a liquid meal in a dose-dependent manner.The inhibitory action of H. pylori lipopolysaccharide wasobserved 2, 4, 8, or 12 hr after the injection. Theseresults suggest for the first time that H. pylorilipopolysaccharide may suppress gastric emptying in along-lasting fashion. It is also suggested that H. pylorimay influence gastric function through its cell wallstructure named lipopolysaccharide. 相似文献
82.
Yoshino K Takeda N Sugimoto M Nakashima K Okumura S Hattori J Sasaki A Kawachi S Takami K Takami R Yasuda K 《Metabolism: clinical and experimental》1999,48(11):1418-1423
Troglitazone and D-chiroinositol have been shown to exert antidiabetic effects by either potentiating or mimicking insulin action. We studied whether pretreatment with these compounds can prevent the deleterious effects of glucosamine on insulin action that may play an important role in hyperglycemia-induced insulin resistance. Normal Wistar rats were pretreated with troglitazone (100 mg/kg/d), D-chiroinositol (100 mg/kg/d), or placebo (saline) for 7 days. Glucosamine (50 micromol/kg/min) was then infused for 210 minutes, and a euglycemic glucose clamp was performed during the last 120 minutes. Pretreatment with troglitazone or D-chiroinositol had no effect on fasting plasma glucose or insulin or basal hepatic glucose output (HGO). Under the euglycemic-hyperinsulinemic (956+/-93 pmol/L) clamp condition, HGO in glucosamine-infused placebo-treated rats was not suppressed, but instead was increased over the basal level, indicative of hepatic insulin resistance. In contrast, HGO failed to increase during glucosamine infusion in rats pretreated with troglitazone but was not normally suppressed. This may indicate a partial improvement in the hepatic insulin resistance. D-Chiroinositol pretreatment had no effect on the glucosamine-induced increase in HGO. The glucose disposal rate (GDR) was 25% lower in rats infused with glucosamine versus saline-infused rats (25.5+/-2.5 v 34.1+/-2.0 mg/kg/min), indicative of peripheral insulin resistance. Pretreatment with D-chiroinositol (34.5+/-2.3 mg/kg/min) prevented the glucosamine-induced decrease in the GDR, indicating an improvement in peripheral insulin resistance. Troglitazone (25.2+/-3.3 mg/kg/min) was without effect. In conclusion, (1) in normal control rats, glucosamine infusion induced hepatic and peripheral insulin resistance; (2) D-chiroinositol, but not troglitazone, pretreatment prevented glucosamine-induced peripheral insulin resistance; and (3) troglitazone, but not D-chiroinositol, partially blocked the glucosamine-induced hepatic insulin resistance. D-Chiroinositol may provide a novel pharmacological approach to hexosamine-induced peripheral insulin resistance. 相似文献
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84.
M Okumura I Sotobata S Isomura T Kondo S Okajima T Shino Y Koike H Hishida 《Japanese heart journal》1979,20(5):577-585
Echocardiographic motions of right ventricular anterior wall (RVAW) were investigated in 71 patients with Wolff-Parkinson-White (WPW) syndrome. According to the criteria of Rosenbaum et al the electrocardiograms were classified as type A in 35 patients and type B in 36. Sixteen type B patients exhibited abnormal RVAW motion, which was characterized by an early onset of the posterior movement before S1 andl also by a premature peak formation before S2. A small step or hump nearly coincident with S1 was observed in 10 of these 16 patients. These findings seem to suggest that both contraction and relaxation of RVAW begin earlier than normal due to anterior right ventricular pre-excitation. RVAW motion was normal in all of type A patients. Echocardiographic investigation of RVAW motion appears to be useful in non-invasive estimation of the site of pre-excitation, especially in type B WPW patients. 相似文献
85.
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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88.
Masaki Naganuma Atsushi Tachibana Takuya Fuchigami Sadato Akahori Shuichiro Okumura Kenichiro Yi Yoshimasa Matsuo Koichi Ikeno Toshiro Yonehara 《Journal of stroke and cerebrovascular diseases》2021,30(7):105791
ObjectivesThe Alberta Stroke Program Early Computed Tomography Score (ASPECTS) is a promising tool for the evaluation of stroke expansion to determine suitability for reperfusion therapy. The aim of this study was to validate deep learning-based ASPECTS calculation software that utilizes a three-dimensional fully convolutional network-based brain hemisphere comparison algorithm (3D-BHCA).Materials and MethodsWe retrospectively collected head non-contrast computed tomography (CT) data from 71 patients with acute ischemic stroke and 80 non-stroke patients. The results for ASPECTS on CT assessed by 5 stroke neurologists and by the 3D-BHCA model were compared with the ground truth by means of region-based and score-based analyses.ResultsIn total, 151 patients and 3020 (151 × 20) ASPECTS regions were investigated. Median time from onset to CT was 195 min in the stroke patients. In region-based analysis, the sensitivity (0.80), specificity (0.97), and accuracy (0.96) of the 3D-BHCA model were superior to those of stroke neurologists. The sensitivity (0.98), specificity (0.92), and accuracy (0.97) of dichotomized ASPECTS > 5 analysis and the intraclass correlation coefficient (0.90) in total score-based analysis of the 3D-BHCA model were superior to those of stroke neurologists overall. When patients with stroke were stratified by onset-to-CT time, the 3D-BHCA model exhibited the highest performance to calculate ASPECTS, even in the earliest time period.ConclusionsThe automated ASPECTS calculation software we developed using a deep learning-based algorithm was superior or equal to stroke neurologists in performing ASPECTS calculation in patients with acute stroke and non-stroke patients. 相似文献
89.
Okumura Takahiro Matsuda Keisuke Fukuoka Yu Dai Junya Shiraishi Naoko 《Journal of artificial organs》2021,24(3):320-326
Journal of Artificial Organs - In Japan, perfusionists who work on other clinical tasks are involved in cardiopulmonary bypass. Moreover, the number of cases they can perform is limited. In view of... 相似文献
90.
Yoshiyuki Sasaki Shinji Osada Ryuutarou Mori Hisashi Imai Yoshihiro Tanaka Nobuhiro Matsuhashi Naoki Okumura Kenichi Nonaka Takao Takahashi Kazuhiro Yoshida 《International journal of medical sciences》2013,10(9):1231-1241
Background: The optimal timing of surgical resection of liver metastasis remains controversial, and guidelines regarding the upper limits of operative indications have not yet been defined. Surgical indication for metastasis from colorectal cancer (CLM) based on results of preoperative chemotherapy and RNF8 was investigated. Methods: Differences in CLM size on CT were evaluated as shrinkage rate/day by dividing tumor shrinkage rates by the interval in days between CT. Levels of RNF8 of resected colorectal cancer and CLM frozen specimen were detected. Results: When the cut line for shrinkage rate at 12 weeks was set at 0.35%, disease-free survival was significantly better in patients with a shrinkage rate >0.35% vs. ≤0.35% (p=0.003). RNF8 expression was significantly higher in Tis (p=0.001). In liver metastasis, RNF8 expression level was significantly lower in patients with partial response to FOLFOX than with stable disease, (p=0.017). Conclusions: A strategy of FOLFOX administration for 12 weeks to patients with low RNF8 expression and hepatectomy planned after 4 weeks rest may be accepted as the best therapeutic option for treating CLM. 相似文献