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111.
Yoshikiyo Akasaka MD PhD ; Kinji Ito PhD ; Kazuko Fujita PhD ; Kazuo Komiyama DDS ; Ichiro Ono MD PhD ; Yukio Ishikawa MD PhD ; Yuri Akishima MD PhD ; Hiroko Sato MD PhD ; Toshiharu Ishii MD PhD 《Wound repair and regeneration》2005,13(4):373-382
To characterize apoptosis in keloids and the mechanisms responsible for this process, the expression of activated caspase-9 and -3 in fibroblasts obtained from keloids was analyzed. Immunohistochemistry revealed that the number of fibroblasts positive for terminal deoxynucleotide transferase-mediated dUTP nick-end labeling (TUNEL) or activated caspase-9 or -3 was low but was significantly higher in keloid tissues than in normal scar tissues. Significant relationships between the number of caspase-positive fibroblasts and TUNEL-positive fibroblasts suggested that the activation of caspase-9 and -3 induces apoptosis in a subpopulation of keloid fibroblasts. All keloid fibroblast cell lines established in this study showed activation of caspase-9 and -3 after serum deprivation for 3 or 4 hours, as shown using Western blotting. Furthermore, serum deprivation-induced apoptosis in a keloid fibroblast line was blocked by a caspase-9 inhibitor (acetyl-Leu-Glu-His-Asp-al), indicating that activation of caspase-9 was necessary for the process of apoptosis in keloid fibroblasts. Although serum deprivation did not significantly change the level of apoptosis protease activating factor-1 in any of the lines, cytochrome c release was detected in cytosolic fractions of the lines after serum deprivation for 3 or 4 hours. These results strongly suggest that keloid fibroblasts are predisposed to apoptosis and cytochrome c release and that caspase-9 activation may underlie regulation of apoptosis in keloid fibroblasts in vivo. 相似文献
112.
Yasushi Sano Hirohisa Machida Kuang‐I. Fu Hiroaki Ito Takahiro Fujii 《Digestive endoscopy》2004,16(Z1):S93-S96
The goal of endoscopic mucosal resection (EMR) is to allow the endoscopist to obtain tissue or resect lesions not previously amenable to standard biopsy or excisional techniques and to remove malignant lesions without open surgery. In this article, we describe the results of conventional EMR and EMR using an insulation‐tipped (IT) electrosurgical knife (submucosal dissection method) for large colorectal mucosal neoplasms and discuss the problems and future prospects of these procedures. At present, conventional EMR is much more feasible than EMR using IT‐knife from the perspectives of time, money, complication, and organ preservation. However, larger lesions tend to be resected in a piecemeal fashion; and it is difficult to confirm whether EMR has been complete. For accurate histopathological assessment of the resected specimen en bloc EMR is desirable although further experience is needed to establish its safety and efficacy. Further improvements of in EMR with special knife techniques are required to simply and safely remove large colorectal neoplasms. 相似文献
113.
Yasuyuki Ito Akira Mori Kiminobu Yonemura Yoichiro Hashimoto Teruyuki Hirano Makoto Uchino 《Clinical neurology》2007,47(9):589-592
We presented here two patients with hemorrhagic infarction occurred during subacute phase of brain embolism. The patients were 71-year-old and 73-year-old men who suffered from brain infarction of the left posterior cerebral artery and right middle cerebral artery territory, respectively. Both of them were diagnosed as having cryptogenic stroke and patent foramen ovale. After transferred to rehabilitation hospitals taking aspirin for a secondary prevention of stroke, they developed hemorrhagic infarction at day 17 and day 19, respectively. Their blood pressure remained within normal range throughout acute and subacute phase. Although most of hemorrhagic infarction occurs within 24 hours of stroke onset, some patients develop symptomatic hemorrhagic infarction even after 10 days. We need to be careful about late-onset hemorrhagic infarction, because many patients are now transferred early to rehabilitation hospitals to facilitate dedicated systematic rehabilitation. 相似文献
114.
Masahiro Fujita Kazuhiko Ito Hiroshi Kawamoto Saburo Kashii Mihoko Norioka Sumie Monden Minoru Okuma 《European journal of haematology》1993,50(4):200-205
Abstract: A cell line, BAD05, derived from B lymphocytes of an adenosine deaminase (ADA; EC 3,5,4,4)-deficient patient could not proliferate in a serum-free medium containing 100 μmol/l deoxyadenosine. When BAD05 was cultured with ADA-positive fibroblasts, the proliferation of BAD05 was improved. BAD05 cell density increased when the initially mixed ratio of fibroblasts/BAD05 was 1/10 or higher, but decreased when the ratio was 1/20 or lower. Deoxyadenosine concentrations in the medium and ATP and deoxyATP (dATP) levels in the BAD05 were measured after 4 hours of coculture at initial BAD05 cell densities of 1 × 105and 1 × 106cells/ml. Deoxyadenosine concentrations in the medium decreased as the density of fibroblasts increased. The dATP level decreased as the mixed ratio rose. The ratio of fibroblasts/BAD05 rather than the cell density of fibroblasts had a larger effect on the dATP levels in BAD05. Under our experimental conditions, ADA-negative cells proliferated well when the ratio of ADA-positive cells/ADA-negative cells was over 1/10. 相似文献
115.
Primary leiomyosarcoma of the thyroid gland 总被引:1,自引:0,他引:1
Osamu Ozaki Kiminori Sugino Takashi Mimura Kunihiko Ito Seiichi Tamai Yasuhiro Hosoda 《Surgery today》1997,27(2):177-180
Primary leiomyosarcoma of the thyroid gland is extremely rare, and to the best of our knowledge only five well-documented
cases have been reported in the world literature. We herein report a 58-year-old female patient with primary leiomyosarcoma
of the thyroid who was successfully treated by total thyroidectomy with a modified neck dissection. Immunohistochemically,
the tumor cells showed positive reactivity to α-smooth muscle actin and vimentin. Radical surgery was thus considered to be
essential in the treatment of this rare but rather aggressive malignancy. 相似文献
116.
117.
Yasunori Utsunomiya Toshiyuki Imasawa Aya Abe Keita Hirano Tetsuya Kawamura Ryuji Nagasawa Tetsuya Mitarai Naoki Maruyama Osamu Sakai 《Clinical and experimental nephrology》1997,1(2):83-91
Background The purpose of this study was to examine the effects of bacterial suporantigens, which can derange the immune response and
contribute to the renal lesions of immunoglobulin A (lgA) nephropathy.
Methods Twenty-five micrograms of a bacterial superantigen, staphylococcal enterotoxin B (SEB), was injected into IgA nephropathy-prone
ddY mice intrathymically when they reached 6 weeks of age. Evaluation included measurement of albumin excretion in urine,
immunoglobulin concentration, and lymphokine production in vitro, as well as analysis of T-cell receptor expression in splenic
T-cell subsets and examination of renal histology by light and fluorescence microscopy.
Results At 40 weeks of age, the serum level of IgA in these mice was substantially increased and the number of Vβ8+ CD4+splenic T-cells was significantly decreased compared with measurements in untreated controls. Both control and SEB-treated
mice excreted less than 30 μg/mL of urinary albumin. In mice given SEB, the amount of interleukin 2 (IL-2) and tumor necrosis
factor-α (T helper 1 [Th1]-type cytokines) produced by the in vitro-stimulated lymphocytes significantly decreased. whereas
that of interleukin 4 (IL-4) and interleukin 6 (IL-6) (Th2-type cytokines) markedly increased compared with measurements in
control mice. At 40 weeks of age, mice given SEB showed marked glomerular hypercellularity and enhanced glomerular C3 deposition
by renal histology, compared with control mice.
Conclusion These results suggest that bacterial superantigen SEB may modify glomerular lesions through activating Th2 cells, while inducing
deletion of Th1 cells in this experimental model. 相似文献
118.
119.
Haruo Ito Zengo Kataumi Shigeyuki Yanagi Kenji Kawamura Hidenori Sumiya Hideki Fuse Jun Shimazaki 《International journal of andrology》1986,9(3):161-169
Testicular development was studied in prepubertal boys with retractile testes. Testicular volume, the diameter of the seminiferous tubules and the number of spermatogonia in the tubules were decreased in cases of unilateral retractile testis, when compared with values for the contralateral normally descended testis. On the other hand, in patients with a unilateral retractile testis and contralateral inguinal testis, there was no difference in the developmental parameters between the two testes. These results suggest that the retractile testis has developmental failures characteristic of a cryptorchid testis and therefore requires orchiopexy. 相似文献
120.
Akihiro Ito Tadateru Takahashi Hiromitsu Watanabe Peter Osa Ogundigie Taro Okamoto 《Cancer science》1992,83(10):1052-1056
Mouse liver tumors occurring in C3H/HeN, C57BL/6N and C3B6F1 hybrid (C3H × C57BL) were studied following 252 Cf fission neutron irradiation. Three strains of mice of both sexes (about 30 mice/group) were irradiated once with 252 Cf at doses of 0,12.5, 50 and 200 cGy. The groups were observed for 13 months after irradiation. The incidence of liver tumors in the non-irradiated controls was 0% in both sexes of CS7BL/6N, 11.7% in males and 0% in females of C3B6F1 and 39.5% in males and 11.4% in females of C3H/HeN mice. In the four strains of mice thus far studied, including B6C3F1 hybrid (CS7BL × C3H) which was previously studied, 252 Cf irradiation has increased the tumor incidence dose-dependently in males and in females, but less effectively in females. The mean number and size of liver tumors were clearly correlated with tumor incidence. The incidence was always highest in C3H/HeN mice of both sexes, followed by B6C3F1, C3B6F1 and C57BL/6N mice. The influence of sex hormones was studied in B6C3F1 mice of both sexes after 200 cGy of 252 Cf irradiation. In males, the incidence of liver tumors was significantly decreased from 55.2% to 23.3% and 25.9% after orchidectomy, and in females it was slightly decreased from 27.6% to 14.8% and 18.8% after ovariectomy. Supplementation of testosterone in orchidectomized mice did not restore the occurrence of liver tumors. 相似文献