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91.
A new method, utilizing microsphere-bound luminol, which makes possible the direct measurement of highly reactive oxygen within phagosomes, was studied. When Freund's complete adjuvant-elicited mouse peritoneal macrophages and luminol-binding microspheres were mixed, the microspheres were engulfed in macrophages and enclosed in phagosomes, where chemiluminescence (CL) was generated, showing the generation of highly reactive oxygen. The reactive oxygen could be quantitatively assayed by measuring the intensity of CL. The addition of cytochalasin B inhibited the CL. CL production by the thioglycollate-elicited macrophages was found to be only a ninth of that by Freund's complete adjuvant-elicited macrophages, though the phagocytic activities were almost equivalent in both cases. 相似文献
92.
The reversibility and cation selectivity of the K(+)-Cl(-) cotransporter (KCC), which normally extrudes Cl(-) out of neurons, was investigated in dissociated lateral superior olive neurons of rats using the gramicidin perforated patch technique. Intracellular Cl(-) activity (alpha[Cl(-)](i)) was maintained well below electrochemical equilibrium as determined from the extracellular Cl(-) activity and the holding potential, where the pipette and external solutions contained 150 mM K(+) ([K(+)](pipette)) and 5 mM K(+) ([K(+)](o)), respectively. Extracellular application of 1 mM furosemide or elevated [K(+)](o) increased alpha[Cl(-)](i). When the pipette solution contained 150 mM Cs(+) ([Cs(+)](pipette)), alpha[Cl(-)](i) increased to a value higher than the passive alpha[Cl(-)](i). An increase of alpha[Cl(-)](i) with the [Cs(+)](pipette) was not due to the simple blockade of net KCC by the intracellular Cs(+) since alpha[Cl(-)](i), with the pipette solution containing 75 mM Cs(+) and 75 mM K(+), reached a value between those obtained using the [K(+)](pipette) and the [Cs(+)](pipette). The higher-than-passive alpha[Cl(-)](i) with the [Cs(+)](pipette) was reduced by 1 mM furosemide, but not by 20 microM bumetanide or Na(+)-free external solution, indicating that the accumulation of [Cl(-)](i) in the [Cs(+)](pipette) was mediated by a KCC operating in a reversed mode rather than by Na(+)-dependent, bumetanide-sensitive mechanisms. Replacement of K(+) in the pipette solution with either Li(+) or Na(+) mimicked the effect of Cs(+) on alpha[Cl(-)](i). On the other hand, Rb(+) mimicked K(+) in the pipette solution. These results indicate that K(+) and Rb(+), but not Cs(+), Li(+), or Na(+), can act as substrates of KCC in LSO neurons. 相似文献
93.
Kawauchi S Okuda S Morioka H Iwasaki F Fukuma F Chochi Y Furuya T Oga A Sasaki K 《Human pathology》2005,36(10):1096-1100
Large cell neuroendocrine carcinoma (LCNEC) of the uterine cervix is a newly introduced category of the revised World Health Organization classification. We reported a case of cervical LCNEC with cytogenetic analysis by comparative genomic hybridization (CGH). The cervical tumor showed moderately increased mitotic activity (8-14 mitotic figures per 10 high-power fields) and focal necrosis, which made it problematic to differentiate from atypical carcinoid. CGH analysis failed to detect chromosome 11q loss that has been reported to be characteristic of pulmonary atypical carcinoids. Furthermore, chromosome 3q amplification, which has been detected frequently in pulmonary small cell carcinomas and LCNECs but not in pulmonary typical and atypical carcinoids, was the most remarkable chromosomal aberration. Although CGH reports are extremely rare in neuroendocrine tumors of the uterine cervix, specific chromosomal aberrations may be useful in their distinction. 相似文献
94.
Yuxiang Ma Daxian Zhang Teruyuki Kawabata Takahiro Kiriu Shinya Toyokuni Koji Uchida Shigeru Okada 《Pathology international》1997,47(4):203-208
The copper and Iron status in the liver of non-tumor bearing Long-Evans Cinnamon (LEC) rats (average age 17 months) was investigated. A direct quantitation of loosely-bound copper and iron was also investigated by using a chelating agent, nitrilotriacetic acid (NTA-chelatable free copper and iron). Besides the total copper and iron contents, the level of NTA-chelatable free copper was also higher in LEC rats than In LEA rats (P<0.05). But for the free iron level there was no signiflcant difference between the two rat groups (P>0.05). The formation of thiobarbituric acid-reactive substances was higher In LEC rats than In LEA rats (P<0.01). The 4–hydroxy-2–nonenal (HNE)-modified proteins were also clearly demonstrated in LEC rat liver. The copper and iron which produced the most important effect In the process of oxidative damage in LEC rats could not be distinguished. Even though free copper, which could induce free radical injuries, was increased in LEC rats, neither tumor-induction nor preneo-plastic lesions in the experimental LEC rats were observed. Therefore it is speculated that the elevation of a free iron is another important factor. Copper and iron, both important translation metals In the body, may participate In the Induction of DNA damage and oncogenesls 相似文献
95.
The relationship of VEGF and PGE2 expression to extracellular matrix remodelling of the tenosynovium in the carpal tunnel syndrome 总被引:1,自引:0,他引:1
Hirata H Nagakura T Tsujii M Morita A Fujisawa K Uchida A 《The Journal of pathology》2004,204(5):605-612
Tenosynovial thickening within the confined space of the carpal tunnel is thought to be the cause of the carpal tunnel syndrome (CTS). However, little is known about the pathological mechanism of tenosynovial thickening. In this study, the role of prostaglandin E(2) (PGE(2)) and vascular endothelial growth factor (VEGF) (two representative molecules that can induce oedema by increasing vascular permeability) was analysed in CTS by using immunohistochemistry and enzyme-linked immunosorptive assay (ELISA). Expression of these molecules was compared with the patients' clinical histories and a temporary increase in production of these molecules was found in cells within the vessels and synovial lining during the intermediate phase of the syndrome when the histology of the tenosynovium changes from oedematous to fibrotic. Statistical analysis clearly demonstrated that there is a close correlation between the expression of PGE(2) and VEGF. Furthermore, immunohistochemical analysis with anti-proliferating cell nuclear antigen (PCNA) revealed that the area with distinct VEGF expression closely matched the area where endothelial cells, vascular smooth muscle cells, and synovial lining cells proliferate. In contrast, despite marked alteration in the extracellular matrix (ECM) component of the tenosynovium, the fibroblasts responsible for most ECM framework production do not proliferate during any phase of CTS. Histological analysis demonstrated that angiogenesis takes place only during the intermediate phase. Since clusters of capillaries and arterioles are often surrounded by type III collagen-rich, disorganized, degenerate connective tissue, which contains fewer fibroblasts than normal, angiogenesis appears to take place as a part of a regenerative reaction that results in fibrosis. These findings strongly indicate that both PGE(2) and VEGF are expressed in the tenosynovium in CTS during the intermediate phase and induce the histological changes seen in the tenosynovium. 相似文献
96.
Evaluation of the clinical pathway for laparoscopic cholecystectomy and simulation of short-term hospitalization. 总被引:1,自引:0,他引:1
Ken Yanagi Koji Sasajima Masayuki Miyamoto Seiji Suzuki Tadashi Yokoyama Hiroshi Maruyama Takeshi Matsutani Yasuo Arima Eiji Uchida Takashi Tajiri 《Nippon Ika Daigaku zasshi》2007,74(6):409-413
The effectiveness of the clinical pathway for laparoscopic cholecystectomy was evaluated, and the efficiency of medical care was analyzed. The duration of hospitalization and the number of National Health Insurance (NHI) points for medical service fees were compared between 86 patients treated after introduction of the clinical pathway (pathway group) and 56 patients treated before introduction of the clinical pathway (pre-pathway group). In the pathway group, variance from the pathway occurred in 24 patients (27.9%) due to postponement of discharge in 7 patients, to earlier discharge in 5 patients, and to insertion of a bile duct catheter in 5 patients. Total and postoperative hospitalization times were significantly shorter in the pathway group than in the pre-pathway group (8.0 +/- 1.6 vs 13.7 +/- 9.0 days, p<0.0001, 5.4 +/- 1.1 vs 6.5 +/- 2.2 days, p<0.0001, respectively). In the pathway group, the total number of NHI points was lower and the number of points per day was higher. By simulation, the total number of NHI points for the 5-day pathway (discharge on postoperative day 3 or earlier) was significantly lower than that for the current 7-day pathway. Moreover, the weekly profit per bed with the 3-day pathway (discharge on postoperative day 1) was more than twice that with the current pathway. The results suggest that the clinical pathway for laparoscopic cholecystectomy is beneficial for patients and useful for the introduction of diagnosis procedure combination in our hospital. 相似文献
97.
Yasunori Higuchi Yoichi Tamura Tomohisa Uchida Keiko Matsuura Naoki Hijiya Shunsuke Yamamoto 《Pathobiology》2004,71(1):1-11
We generated transgenic mice expressing osteopontin (OPN) under the control of the alpha(1)-antitrypsin promoter. These mice (OPN-T mice) expressed OPN mRNA in liver and kidney, and released a large amount of plasma OPN, which increased after stimulation with turpentine oil. Before sensitization, the number of CD4+ T cells in lymph nodes was significantly higher in OPN-T than nontransgenic mice, and that in spleen was slightly higher, whereas that of CD8+ T cells was no different between OPN-T and nontransgenic mice. After sensitization, the CD4+ T cell numbers in spleen increased significantly, while there were almost no changes in the CD8+ T cells in lymph nodes and spleen. The intensity of contact hypersensitivity responses to 2,4-dinitrofluorobenzene (DNFB) was obviously enhanced in OPN-T mice. In the delayed-type hypersensitivity (DTH) model elicited by DNFB, the number of CD8+ T cells among DNFB-2,4,6-trinitrobenzenesulfonic acid (TNBS)-peritoneal exudate cells was significantly higher in OPN-T than nontransgenic mice, while there was almost no difference in that of CD4+ T cells. Adoptive transfer experiments revealed that the enhanced reactivity is carried by CD4+ and CD8+ T cells, respectively, although the ability of transferring DTH was significantly lower in CD8+ than in CD4+ T cells. The enhancement of CD8+ T cell migration was observed in OPN-T mice. These results suggest that OPN induces a proliferation of effector CD4+ and CD8+ cells in cell-mediated reactions and plays a role in the migration of CD8+ T cells. 相似文献
98.
Yuji J Masaki T Yoshida S Kita Y Feng H Uchida N Yoshiji H Kitanaka A Watanabe S Kurokohchi K Kuriyama S 《International journal of molecular medicine》2004,13(5):721-728
The adaptor molecule Shc is a proto-oncogene product, and it is known to be associated with cell proliferation. However, the role of Shc in the proliferation and regeneration of hepatocytes remains unknown. In the present study, we report that p46 Shc is specifically expressed in the nuclei of proliferative (or regenerative) hepatocytes, suggesting that p46 Shc protein plays a role in hepatocellular proliferation. The expression of Shc was analyzed in liver tissue after partial hepatectomy (PH) or sham operation in Wistar rats by using immunohistochemistry and/or Western blot analysis. In addition, the expression of various cell cycle-related proteins, such as Cdk4, cyclin D1, PCNA, and Cdk1 was analyzed in the tissues of regenerating rat liver. Furthermore, the tyrosine phosphorylation of Shc was studied in liver tissue after PH or sham operation by immunoprecipitation using a monoclonal phosphotyrosine antibody. Although the protein levels of p52 Shc were unchanged in liver tissues after PH or sham operation, tyrosine phosphorylation was detected only in the regenerating rat liver after PH. The levels of p46 Shc protein were markedly increased in liver tissues during the liver regenerative process. In contrast, p66 Shc was not detected in the liver tissues after PH or sham operation. Western blotting and immunohistochemistry showed that the main location of p46 Shc was in the nuclei of proliferating hepatocytes after PH. These data suggest that p46 Shc expressed in hepatocellular nuclei may be closely related to the proliferation of hepatocytes. Therefore, it is suggested that p46 Shc expressed in hepatocellular nuclei may be a useful marker for detecting hepatocytes with high proliferative activity. 相似文献
99.
H Yoshimura H Uchida H Ohishi N Honda S Ohue Y Kinoshita M Katsuragi N Matuso Y Hosogi M Hatakeyama 《European journal of radiology》1986,6(3):195-198
The hepatic arteries of 122 patients were analysed on angiography to identify the left medial segment of the liver. Left medial arterial branches were classified into three types: type I arising from the left hepatic artery on the umbilical portion of the portal vein; type II arising from proximal portion of left hepatic artery before reaching the umbilical portion of the portal vein; type III arising from right hepatic artery. Incidence of each type is 37.2%, 35.8% and 27.0%, respectively. The artery frequently kinks at the right side of the umbilical portion of the portal vein and a total of incidence is 68% and that of each type is 23.5%, 89.8% and 100%, respectively. We call this characteristic kinking point of the left medial arterial branches, the "M-point". 相似文献
100.
Hideyuki Arima Yu Yamato Kimihito Sato Yoshihiro Uchida Toshiyuki Tsuruta Kanehisa Hashiguchi Hajime Hamamoto Eiichiro Watanabe Kaoru Yamanaka Tomohiko Hasegawa Go Yoshida Tatsuya Yasuda Tomohiro Banno Shin Oe Hiroki Ushirozako Tomohiro Yamada Koichiro Ide Yuh Watanabe Yukihiro Matsuyama 《Journal of orthopaedic science》2021,26(4):577-583
BackgroundSagittal spino-pelvic malalignment in patients with chronic low back pain (CLBP) have been reported in the past, which may also affect cervical spine lesions. The purpose of this study is to investigate the cervical alignment in patients with CLBP.MethodOf the patients who visited an orthopedic specialist due to low back pain lasting more than three months, 121 cases (average 71.5-years-old, 46 male and 75 female) with whole standing spinal screening radiographs were reviewed (CLBP group). Cervical parameters included cervical lordosis (CL), C2–C7 sagittal vertical axis (C2-7 SVA), and the T1 slope minus CL (T1S-CL). Cervical spine deformity was defined as C2-7 SVA >4 cm, CL <0°, or T1S-CL ≧20°. We compared the cervical alignment of these patients with 121 age and gender matched volunteers (control group).ResultsThe prevalence of cervical spine deformity was significantly higher in the CLBP group than in the control group (20.7% vs. 10.7%, P = 0.034). The mean CL was smaller in the CLBP group than in the control group (16.1° vs. 21.4°, P = 0.002). The mean C2-7 SVA was 17.6 mm vs. 18.7 mm in the CLBP group and in the control group, respectively (P = 0.817). The mean T1S-CL was larger in the CLBP group than in the control group (9.1° vs. 3.5°, P < 0.001). Multivariate analysis showed that people with CLBP were more likely to have cervical deformities than people without CLBP (odds ratio 2.16, 95% confidence interval 1.006 to 4.637).ConclusionsThis study results suggest that people with CLBP present with worse cervical sagittal alignment and higher prevalence of cervical spine deformities than age and gender matched volunteers with no CLBP. This means CLBP impacts cervical spine lesions negatively.Level of evidenceⅣ 相似文献