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61.
Suzuki Hisamitsu; Ota Kazuo; Ohno Ryuzo; Masaoka Toru; Shibata Hirotoshi; Kimura Ikuro; Amaki Ichita; Miura Yasusada; Uzuka Yoshiro; Kawato Masafumi; Shirakawa Shigeru; Hirota Yutaka; Maekawa Tadashi; lmai Kuniyuki; Takaku Fumimaro; Shimoyama Masanori; Kitahara Takeshi; Oguro Masao; Kozuru Mitsuo; Kawagoe Hiroya; Nakamura Toru; Yamada Kazumasa 《Japanese journal of clinical oncology》1989,19(4):338-347
Patients with acute (2,569) and chronic (957) leukemia diagnosedat 19 institutes took part in the study on the "MultidisciplinaryTreatment of Leukemia" between 1971 and 1985 and were investigatedretrospectively. By dividing the 15 years into three five-yearperiods, we were able to compare patient ratios in the differentperiods. The proportions of acute to chronic leukemia casesshowed no obvious change; however, the proportions of casesdiagnosed as acute lymphocytic leukemia in acute leukemia showeda significant increase. The main chemotherapeutic drugs usedduring the three time periods were cytarabine or its analogues,the anthracyclines, 6-mercaputopurine and prednisolone, againstacute myelogenous leukemia, and the vinca alkaloids, prednisoloneand the anthracyclines against acute lymphocytic leukemia. Therate of complete remission from acute myelogenous leukemia mademarked progress, from 45.1% during 19711975 to 62.3%during 19811985, but that of acute lymphocytic leukemiashowed no significant progress, being 65% during 19711975and 69.7% during 19811985. The durations of remission,however, and the survival times for patients with acute lymphocyticleukemia, as well as for those with acute myelogenous leukemia,became significantly longer over the three periods. Median survivaltimes from chronic myelocytic leukemia were 3740 mo inall three periods, showing no progress. There was a better prognosisin cases of chronic myelocytic leukemia with, than without,Philadelphia chromosome. Except for a low incidence of chroniclymphocytic leukemia in Japan, adult leukemia patients' characteristicsand prognoses seem to be almost the same in Japan as in theU.S.A. and Europe. 相似文献
62.
Uchida Y Ohshima T Sasaki Y Suzuki H Yanai S Yamashita N Nakamura F Takei K Ihara Y Mikoshiba K Kolattukudy P Honnorat J Goshima Y 《Genes to cells : devoted to molecular & cellular mechanisms》2005,10(2):165-179
Collapsin response mediating protein-2 (CRMP2) has been identified as an intracellular protein mediating Semaphorin3A (Sema3A), a repulsive guidance molecule. In this study, we demonstrate that cyclin-dependent kinase 5 (Cdk5) and glycogen synthase kinase 3beta (GSK3beta) plays a critical role in Sema3A signalling. In In vitro kinase assay, Cdk5 phosphorylated CRMP2 at Ser522, while GSK3beta did not induce any phosphorylation of CRMP2. Phosphorylation by GSK3beta was exclusively observed in Cdk5-phosphorylated CRMP2, but barely in CRMP2T509A. These results indicate that Cdk5 primarily phosphorylates CRMP2 at Ser522 and GSK3beta secondarily phosphorylates at Thr509. The dual-phosphorylated CRMP2, but not non-phosphorylated or single-phosphorylated CRMP2, is recognized with the antibody 3F4, which is highly reactive with the neurofibrillary tangles of Alzheimer's disease. 3F4 recognized the CRMP2 in the wild-type but not cdk5-/- mouse embryonic brain lysates. The phosphorylation of CRMP2 at Ser522 caused reduction of its affinity to tubulin. In dorsal root ganglion neurones, Sema3A stimulation enhanced the levels of the phosphorylated form of CRMP2 detected by 3F4. Over-expression of CRMP2 mutant substituting either Ser522 or Thr509 to Ala attenuates Sema3A-induced growth cone collapse response. These results suggest that the sequential phosphorylation of CRMP is an important process of Sema3A signalling and the same mechanism may have some relevance to the pathological aggregation of the microtubule-associated proteins. 相似文献
63.
Koyanagi M Imanishi K Arimura Y Kato H Yagi J Uchiyama T 《International immunology》2004,16(2):315-326
To determine the levels of maturation and differentiation ofmurine CD4 single-positive (SP) T cells, we compared the secondaryresponses of staphylococcal enterotoxin A (SEA)-induced neonatalthymic, adult thymic and adult splenic CD4 SP T cell blastsprepared from whole or heat-stable antigenlow CD4 SP T cells.Proliferative responses upon re-stimulation with SEA were strongin adult splenic CD4 SP T cell blasts, but quite weak in neonatalthymic and adult thymic CD4 SP T cell blasts. SEA-induced IL-2production was weaker in neonatal thymic blasts than in theadult splenic CD4 SP T cell blasts. In contrast, SEA-inducedIL-4 production was high in neonatal thymic CD4 SP T cell blasts,and low in adult splenic and thymic CD4 SP T cell blasts. Expressionof GATA-3, that directs production of IL-4 in T cells, examinedat protein and mRNA levels, was higher in neonatal thymic cellsthan in adult thymic and splenic cells. These results suggestthat neonatal and adult thymic CD4 SP T cells in the final stageof maturation are relatively immature compared with adult splenicCD4 SP T cells. The cytokine production profile of neonatalthymic CD4 SP T cells suggests that they are inclined towardsa Th2 response. 相似文献
64.
Masafumi Hara Yutaka Tsutsumi Keiichi Watanabe Sohtaro Suzuki Norio Tani Takeshi Miwa 《Pathology international》1985,35(4):831-840
Six solitary gastric polyps in the acid-secreting fundic mucosa were histo-chemically investigated using the mucin histochemistry, immunoperoxidase method, and silver methods for endocrine cells. Histologically, the polyps were grouped into three types : they largely consisted of either hyperplastic foveolar cells (group 1), normal-appearing fundic gland cells with mild cystic changes (group 2) or hyperplastic fundic gland cells with cystic dilatation (group 3). The presence of parietal cells and mucous neck cells was confirmed in all polyps by the immunoperoxidase method using parietal cell autoantibody and the paradoxical Concanavalin A staining, respectively. Regarding the endocrine component, somatostatin-containing cells, Grimelius-positive argyrophil cells, and Fontana-Masson-positive enterochromaffin cells were scattered in the fundic gland area of the polyps as well as in the surrounding normal-appearing fundic mucosa. Gastrin-containing cells were absent. In one of the group 2 polyps and both group 3 polyps, a varying number of glicentin-containing cells were found among the fundic gland components : In one polyp in group 3, glucagon immunoreactivity was detected in the glicentin-containing cells. These findings suggest that some of the polyps express characteristics of the fetal fundic mucosa, since glicentin and glucagon immunoreactivities in normal human stomach have been detected exclusively in the fetal fundus. ACTA PATHOL. JPN. 35: 831–840, 1985. 相似文献
65.
Activation of protease-activated receptor 2 stimulates proliferation and interleukin (IL)-6 and IL-8 secretion of endometriotic stromal cells 总被引:3,自引:0,他引:3
Hirota Y Osuga Y Hirata T Harada M Morimoto C Yoshino O Koga K Yano T Tsutsumi O Taketani Y 《Human reproduction (Oxford, England)》2005,20(12):3547-3553
BACKGROUND: Inflammation has been proposed to play essential roles in the pathophysiology of endometriosis, in which neutrophils and mast cells have been suggested to be involved. We studied whether the protease-activated receptor 2 (PAR2), which is activated by enzymes from neutrophils and mast cells, in endometriotic stromal cells (ESC) has any implication in the development of the disease. METHODS: Cultured ESC were stimulated with various concentrations of a specific PAR2 agonist peptide. Proliferating activity of the cells was determined using immunostaining of proliferating cell nuclear antigen (a cell proliferation marker), 5-bromo-2'-deoxyuridine incorporation into DNA and cell count. The concentrations of interleukin (IL)-6 and IL-8 were measured using specific enzyme-linked immunosorbent assay kits. The phosphorylation of three mitogen-activated protein kinases (MAPK), i.e. p38 MAPK, p42/44 MAPK and stress-activated protein Kinase/c-jun N terminal Kinase, in ESC was examined with Western blot analysis. RESULTS: Activation of PAR2 stimulated the proliferation of ESC and the secretion of IL-6 and IL-8 from ESC in a dose-dependent manner. Activation of PAR2 stimulated the phosphorylation of all three MAPK, and inhibitors of each MAPK suppressed the PAR2 activation-induced proliferation of ESC. CONCLUSIONS: The activation of PAR2 in ESC may be involved in the pathophysiology of endometriosis by inducing the growth and inflammation of endometriotic lesions. 相似文献
66.
CD44 variant 6 in endometrioid carcinoma of the uterus: its expression in the adenocarcinoma component is an independent prognostic marker 总被引:10,自引:0,他引:10
Hoshimoto K Yamauchi N Takazawa Y Onda T Taketani Y Fukayama M 《Pathology, research and practice》2003,199(2):71-77
The expression of variant isoforms of CD44 (CD44v) correlates with the metastatic potential of various carcinomas. In endometrial cancer, however, the significance of CD44v-expression as a prognostic indicator has not been fully investigated, nor has it been compared with that of p53, estrogen receptor or Ki67. Surgical material consisted of 14 atypical endometrial hyperplasias (AEH) and 163 endometrial carcinomas (EC). Expression of CD44s, v3 and v6 in carcinoma tissue, and other prognostic markers were immunohistochemically evaluated. The expression in the squamous differentiation was strictly excluded for the evaluation of immunohistochemistry, because the significance was different from that in the adenocarcinoma component. CD44s was frequently expressed in AEH and EC. On the other hand, CD44v3- and v6-positivities were rare or nonexistent in AEH, but were observed in 8 and 35% of EC, respectively. CD44v3-expression correlated significantly with histologic grade and lymph node metastasis. However, there was no correlation between CD44v6 expression and any clinicopathologic factor, nor were other prognostic markers expressed. Univariate analysis revealed that each CD44 was a prognostic determinant in the patients with EC. However, employing multivariate analysis, there were only three independent factors: p53 overexpression, CD44v6 expression and myometrial invasion. CD44v6 expression in the adenocarcinoma component may directly affect the behavior of carcinoma and the prognosis of patients with EC. 相似文献
67.
Repair of infarcted myocardium mediated by transplanted bone marrow-derived CD34+ stem cells in a nonhuman primate model 总被引:6,自引:0,他引:6
Yoshioka T Ageyama N Shibata H Yasu T Misawa Y Takeuchi K Matsui K Yamamoto K Terao K Shimada K Ikeda U Ozawa K Hanazono Y 《Stem cells (Dayton, Ohio)》2005,23(3):355-364
Rodent and human clinical studies have shown that transplantation of bone marrow stem cells to the ischemic myocardium results in improved cardiac function. In this study, cynomolgus monkey acute myocardial infarction was generated by ligating the left anterior descending artery, and autologous CD34(+) cells were transplanted to the peri-ischemic zone. To track the in vivo fate of transplanted cells, CD34(+) cells were genetically marked with green fluorescent protein (GFP) using a lentivirus vector before transplantation (marking efficiency, 41% on average). The group receiving cells (n = 4) demonstrated improved regional blood flow and cardiac function compared with the saline-treated group (n =4) at 2 weeks after transplant. However, very few transplanted cell-derived, GFP-positive cells were found incorporated into the vascular structure, and GFP-positive cardiomyocytes were not detected in the repaired tissue. On the other hand, cultured CD34(+) cells were found to secrete vascular endothelial growth factor (VEGF), and the in vivo regional VEGF levels showed a significant increase after the transplantation. These results suggest that the improvement is not the result of generation of transplanted cell-derived endothelial cells or cardiomyocytes; and raise the possibility that angiogenic cytokines secreted from transplanted cells potentiate angiogenic activity of endogenous cells. 相似文献
68.
Nobuyuki Tanaka Kazumasa Sugihara Tetsuyo Odajima Masafumi Mimura Yutaka Kimijima Shizuko Ichinose 《Medical Electron Microscopy》2002,35(3):127-138
Oral squamous cell carcinoma is the most common oral malignancy, and we performed electron microscopic and immunohistochemical investigation of the tumor. In patients with cervical metastasis, microvilli were developed and a small number of desmosomes were found, regardless of the width of the intercellular spaces. In patients without the metastasis, few microvilli were found in relatively wide intercellular spaces, or numerous microvilli were found in narrow intercellular spaces, and a large number of desmosomes were shown. However, these findings were different from those of tumors that had received radiotherapy, in which numerous microvilli and a small number of desmosomes were found in the nonmetastatic cases. Transferrin receptor, which is a marker of cell proliferation, was localized on the cell membrane, especially in microvilli. Ultrastructural similarity between the primary tumor and the metastatic tumor was recognized, however, the features of microvilli, desmosomes, and the intercellular spaces differed between them in most cases. It is suggested that microvilli might be related to the metastasis of oral squamous cell carcinoma cells. Immunohistochemically, the protein expression of p53 and pRb2/p130 was related to the clinical course of the patients with oral squamous cell carcinoma; the mechanism of the synthesis of these proteins should be investigated in order to understand the biological behavior of the tumor. 相似文献
69.
Nobuyuki Tanaka Masafumi Mimura Yutaka Kimijima Kodo Sasaki Shizuko Ichinose Teruo Amagasa 《Medical Electron Microscopy》2002,35(4):204-216
Sarcoma of the oral region is extremely rare and ultrastructural studies of the tumor are limited in number. We collected oral sarcomas, such as fibrosarcoma, malignant fibrous histiocytoma, liposarcoma, leiomyosarcoma, rhabdomyosarcoma, angiosarcoma, alveolar soft-part sarcoma, solitary plasmacytoma, and osteosarcoma, and performed ultrastructural studies of these tumors. The value of these studies for an understanding of the biological behavior of the tumors was then investigated. In these studies, electron microscopic examinations of oral sarcoma were of assistance in our attempt to establish correct diagnosis and histogenesis. Data from the studies of oral sarcoma by light microscopy, electron microscopy, and immunohistochemistry should be accumulated. 相似文献
70.
Rapid and efficient generation of lentivirally gene-modified dendritic cells from DC progenitors with bone marrow stromal cells 总被引:4,自引:0,他引:4
Sumimoto H Tsuji T Miyoshi H Hagihara M Takada-Yamazaki R Okamoto S Ikeda Y Takahashi T Kawakami Y 《Journal of immunological methods》2002,271(1-2):153-165
Since dendritic cells (DC) play pivotal roles in both innate and adaptive immunity, DC can be a good target for immuno-gene therapy. However, the optimal generation method for gene-modified DC has not yet been well exploited. CD34+ cells from cord blood (CB), bone marrow (BM), or peripheral blood (PB) were expanded in a medium containing stem cell factor (SCF), flt 3 ligand (Flt3L) and thrombopoietin (TPO) with or without HESS-5, a murine BM stromal cell line, for 2 weeks (the first expansion step), then differentiated to DC in a medium containing granulocyte-macrophage colony-stimulating factor (GM-CSF), flt 3 ligand (Flt3L), stem cell factor (SCF), tumor necrosis factor-alpha (TNF-alpha), IL-4, and lipopolysaccharide (LPS) for 9 days (the second differentiation step). DC progenitors were transduced with human immunodeficiency virus (HIV) vectors at different time points during the second step. Use of HESS-5 during the first step resulted in more DC generation than without it (cell expansion: CB, 10,461 vs. 354-fold; BM, 962 vs. 225-fold; peripheral blood mononuclear cell (PBMC), 8,506 vs. 240-fold; %DC: CB, 83.4% vs. 76.9%; BM, 83.6 vs. 69.8%; PBMC, 85.9 vs. 60.5%). Gene transduction to the in vitro expanded DC progenitors at day 3 during the second step, resulted in better final yield of the gene-modified DC than that to those at day 0 or day 6 (as much as 44% of DC expressed green fluorescence protein (GFP) as a transgene) and the transduction efficiency correlated with endocytic ability and percent of S phase. DC transduced with an HIV vector encoding a melanoma antigen, MART-1, were adequately recognized by specific anti-MART-1 CTL. The two-step culture method with HESS-5 is useful for rapid expansion of DC progenitors and subsequent lentiviral gene transduction to DC. 相似文献