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31.
Effects of halothane on spinal dorsal horn WDR(wide dynamic range) neuronal activity in cats 总被引:1,自引:0,他引:1
H Nagasaka S Nakamura T Genda T Miyazaki K Aikawa N Matsumoto I Matsumoto T Hori I Sato 《Masui. The Japanese journal of anesthesiology》1991,40(7):1096-1101
The effects of halothane (0.2%, 0.5%, and 1.0%) on the spinal dorsal horn wide dynamic range (WDR) neuronal activity was studied in either spinal cord intact or spinal transected cats. Extracellular activity was recorded in the dorsal horn from single WDR neurons responding to noxious and non-noxious stimuli applied to the cutaneous receptive fields on the left hind foot pads of intact or decerebrate, spinal cord transected (L 1-2) cats. When 10 micrograms of bradykinin was injected into the femoral artery ipsilateral to the recording site as the noxious test stimulus in the spinal cat, all of 7 WDR neurons gave excitatory responses which were not depressed by 0.2% and 0.5% halothane but were depressed significantly by 1.0%. On the other hand, when the injection of 10 micrograms of bradykinin into the femoral artery ipsilateral to the recording site was used in the intact cat, 7 of 14 WDR neurons (50%) gave excitatory responses, which were not depressed by 0.2% halothane but were significantly depressed by 0.5% and 1.0% halothane, and 7 of 14 WDR neurons (50%) gave inhibitory responses, which were significantly depressed by 0.2%, 0.5%, and 1.0% halothane. We have found that halothane reduces the excitation as well as the inhibition of dorsal horn WDR neuronal activity induced by bradykinin injection. 相似文献
32.
Cloning of regions required for contact hemolysis and entry into LLC-MK2 cells from Shigella sonnei form I plasmid: virF is a positive regulator gene for these phenotypes. 总被引:10,自引:5,他引:5 下载免费PDF全文
Two distinct regions required for both contact hemolysis and entry into LLC-MK2 cells were cloned into Escherichia coli from the Shigella sonnei form I plasmid, pSS120. The first region was cloned into an E. coli HB101 strain containing noninvasive Tn1 insertion mutants of the form I plasmid, and expression of ipa (invasion plasmid antigen) gene products was restored. The plasmid carrying the first region was then transformed into E. coli lacking the form I plasmid, and additional DNA fragments from the form I plasmid were cloned into the same recipient on compatible vectors. Five of these double transformants were found to be positive for contact hemolysis activity. Restriction analysis of these five clones indicated that the previously reported ipa locus and the invA locus were present on the second plasmid region. Only the strains carrying both of these regions were active in contact hemolysis and cell invasion assays. Several proteins, including the a, b, c, and d proteins encoded by the ipa genes, were detected in the double transformants by Western blot (immunoblot) analysis with serum of a monkey convalescing from shigellosis. A positive regulator was suggested to exist in the first region, since the amounts of most of these proteins were simultaneously increased in the presence of this region. Subcloning and nucleotide sequencing indicated that this positive regulator gene was virF. Product analysis of the virF gene with minicells showed that two peptides (30 and 21 kilodaltons) were synthesized and that at least the 30-kilodalton protein was essential for regulation of the ipa genes. 相似文献
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34.
Keisuke Mitsuoka Sosuke Miyoshi Yukio Kato Yoshihiro Murakami Rie Utsumi Yoshiyuki Kubo Akihiro Noda Yukio Nakamura Shintaro Nishimura Akira Tsuji 《Journal of nuclear medicine》2008,49(4):615-622
H+/peptide transporter, PEPT1, is functionally expressed in some human cancer cell lines and might be a candidate molecular target for detection of cancers in vivo using PET. The aim of the present study was to establish a novel tumor-imaging technology using a PET tracer targeted to H+/peptide transporter(s). We also compared the tracer with 18F-FDG, focusing on the specificity of their accumulation between tumor and inflammatory tissues. METHODS: A dipeptide PET tracer, 11C-glycylsarcosine (11C-Gly-Sar), was injected intravenously into athymic mice transplanted with human pancreatic, prostate, and gastric cancer cells. The distribution patterns of 11C-Gly-Sar and 18F-FDG in the tumor-bearing mice, and in mice with inflammatory tissue, were assessed by imaging with a positron planar imaging system (PPIS). Tissue distributions of tracer radioactivity were also measured. The expression levels of PEPT1 and PEPT2 (PEPTs) proteins in tumor xenografts and inflammatory tissue were examined by immunohistochemical analysis. The messenger RNA expression levels of PEPTs in 58 available cancer cell lines were quantified by means of real-time polymerase chain reaction. RESULTS: All 3 tumor xenografts were well visualized with the PPIS after injection of 11C-Gly-Sar. Expression of PEPTs in those xenografts was confirmed by immunohistochemical analysis. Tumor-to-blood concentration ratios of 11C-Gly-Sar increased in a time-dependent manner and were much higher than unity. Most of the radioactivity found in the tumor tissue was recovered as the intact tracer. These results indicated that 11C-Gly-Sar was taken up by the PEPTs in tumor xenografts. It is noteworthy that 11C-Gly-Sar was minimally present in inflammatory tissues that expressed no PEPT1 or PEPT2 protein, whereas 18F-FDG was highly accumulated, with the values of the selectivity index being >25.1 and 0.72 for 11C-Gly-Sar and 18F-FDG, respectively. The mRNAs of PEPT1 and PEPT2 were expressed in 27.6% and 93.1%, respectively, of the cancer cell lines examined in the present study. CONCLUSION: The present study indicates that 11C-Gly-Sar is a promising tumor-imaging agent and is superior to 18F-FDG for distinguishing between tumors and inflammatory tissue. Because PEPTs were ubiquitously expressed in various types of tumor cells examined, 11C-Gly-Sar could be useful for the detection of many types of cancers. 相似文献
35.
Ung-il Chung Hiroshi Kawaguchi Tsuyoshi Takato Kozo Nakamura 《Journal of orthopaedic science》2004,9(4):410-414
Mammalian bones have three distinct origins (paraxial mesoderm, lateral plate mesoderm, and neural crest) and undergo two different modes of formation (intra-membranous and endochondral). Bones derived from the paraxial mesoderm and lateral plate mesoderm mainly form through the endochondral process. During this process, hypertrophic chondrocytes play a vital role in inducing both osteogenesis and angiogenesis. One of the essential osteogenic factors secreted from hypertrophic chondrocytes is Indian hedgehog (Ihh). In contrast, bones derived from the neural crest mainly form through the intramembranous pro-cess and do not require Ihh. Thus, depending on their origin, bones have distinct signaling properties, which need to be considered in the research and application of bone biology.Presented at the 18th Annual Research Meeting of the Japanese Orthopaedic Association, Kitakyushu, Japan, October 17, 2003 相似文献
36.
37.
M Okada S Matsuda S Kozawa S Yasuoka K Ogawa K Nakamura 《Japanese circulation journal》1986,50(9):888-894
Between 1970 and 1985, 221 patients with coronary artery occlusive disease underwent aorto-coronary bypass (A-C bypass) and other procedures. Among these patients, 187 had A-C bypass alone and A-C bypass in addition to correction of valvular lesions or arterialization of the coronary vein, myocardial puncture by laser. The remaining 34 had surgical corrections for myocardial infarction and its complications. Subjects were 100 patients who underwent A-C bypass alone over 6 months ago and whose follow-up study could be performed in 93 survival cases [corrected]. Subsequently, 94% of the patients have met the criteria for grade I of NYHA functional capacity and have returned to normal work at a mean of 4 years and 2 months after surgery. Improved left ventricular function has been maintained postoperatively in the patients with complete revascularization. Improved operative technique, in addition to intraoperative balloon angioplasty and onlay patch grafting, have increased the patency rate (78% in 1 mm, 94% in 2 mm of coronary diameter) of the grafts with postoperative anticoagulant therapy. On the basis of our long-term observations, coronary bypass surgery, particularly in complete revascularization, provides for significant improvement in both the quality and life expectancy of patients with severe coronary heart disease. Treadmill exercise test and magnetic resonance image (MRI) were useful, non-invasive and acceptable examinations in long-term follow up. 相似文献
38.
Benign schwannoma of the pancreas 总被引:2,自引:0,他引:2
Labile Togba Soumaoro Kenichi Teramoto Tohru Kawamura Noriaki Nakamura Takahiro Sanada Kenichi Sugihara Shigeki Arii 《Journal of gastrointestinal surgery》2005,9(2):288-290
Reported cases of intrapancreatic schwannomas have recently increased in the literature. However, none of these cases were
diagnosed clearly as schwannoma preoperatively. We herein describe the clinicopathologic findings of a solitary benign schwannoma
occurring in the head of the pancreas. Additionally, the differential diagnosis versus other cystic- and solid-appearing pancreatic
masses is briefly discussed. 相似文献
39.
40.
Masahiko Harano Masatoshi Eto Motonobu Nakamura Yoshihiro Hasegawa Motonori Kano Akito Yamaguchi Seiji Naito 《International journal of urology》2007,14(2):112-117
OBJECTIVE: To assess the functional results, health-related quality of life (QOL) outcomes, and complications in patients with an ileal neobladder in comparison to those with cutaneous diversion (ileal conduit and cutaneostomy). METHODS: Between September 1992 and February 2003, we consecutively performed an ileal neobladder (the Studer method) in 30 patients and cutaneous diversion in 38 patients. In August 2004, questionnaires were mailed to 54 patients. The questionnaire included the validated health-related quality of life (QOL) questionnaire, SF-36 General Health Survey, and a urinary incontinence questionnaire. We also evaluated the functional results in patients with an ileal neobladder and the postoperative complications in patients with both urinary diversions. RESULTS: The data from 41 patients (21 ileal neobladder procedures and 20 cutaneous diversions) were available for the analysis. No differences in the overall QOL were observed between the two groups. Complete daytime and night-time urinary continence was achieved in the 21 patients (100%) and 13 patients (61.9%), respectively. The mean value of the maximum flow rate was 15 +/- 12 mL/min in the 21 neobladder patients. There were 19 early complications in 18 patients (60.0%) and seven late complications in six patients (20.0%) with an ileal neobladder. However, there were 15 early complications in 14 patients (36.8%) and eight late complications in six patients (15.8%) with cutaneous diversions. CONCLUSION: The findings regarding the health-related QOL and the frequency of complications in the neobladder group and those in the cutaneous diversion group were similar. However, the functional results and the status of urinary continence in the neobladder patients were satisfactory. 相似文献