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71.
72.
Takao Kato Tsunehito Kimura Ryuhei Miyakawa Shinichi Tanaka Takako Kamio Kazuko Yamamoto Kyoichi Hamano Motohiko Aiba Makio Kawakami 《Surgery today》1996,26(2):105-114
This study was undertaken to assess blood vessel invasion (BVI) and other histologic features to determine the best method of histologic prognosis in node-negative breast cancer patients. The prognostic significance of the clinicopathological findings was evaluated in 70 patients with nodenegative breast cancer among 135 patients operated on between 1971 and 1981. The prognostic factors investigated included BVI, peritumor lymphatic invasion, clinical tumor size, nuclear grade, histological grade, mitotic grade, and tumor necrosis. BVI was detected by factor VIII-related antigen and elastica van Gieson staining. BVI-negative patients had a 20-year cumulative survival of 93.7%, versus 74.7% for BVI-positive patients (P=0.0294). The clinical tumor size also correlated well with prognosis (P<0.0001). However, the other histologic features did not correlate with a poor prognosis. Moreover, we retrospectively examined the effect of postoperative chemotherapy for patients with BVI and T3, and the prognosis of those given chemotherapy seemed to be better than that of those who were not. Tumors measuring more than 51 mm and BVI may thus represent adverse prognostic factors in node-negative breast cancer patients.Presented at the 35th World Congress of the International Society of Surgery in Hong Kong, August, 1993. 相似文献
73.
Taiji Kunitomi M.D. Hirotoshi Takigawa M.D. Makio Sugita M.D. Shin Nouno M.D. Masayuki Suemune M.D. Masakatsu Inoue M.D. Nobuyuki Kodani M.D. Megumi Oda M.D. Masanori Ikeda M.D. 《Pediatrics international》1990,32(1):16-19
Antibody-dependent cellular cytotoxicity (ADCC) and natural killer (NK) ativity were examined using MT-2 cells persistently infected by HTLV-1 as target cells, and mononuclear cells as effector cells, from helathy one-week-old newborn babies, infants, children and adults. More than 10% of ADCC was observed in 17 newborn babies out of 22 (77.3%) and in all 67 healthy one-month-old babies to adults, by adding serum from anti-HTLV-1 positive carriers. When anti-HTLV-1 negative serum was added, less than 10% of ADCC was observed. If infants without anti-HTLV-1 antibodies were breast-fed they had the possibility of HTLV-1 vertical transmission. There was no significant decrease in NK activity between 90 healthy newborn babies, infants, children, or adults. These results suggest that ADCC and NK activity protect against the transmission of HTLV-1 from mother to child. 相似文献
74.
Makio Ogawa 《International journal of hematology》2002,76(1):151-151
It has been generally held that human hematopoietic stem cells are lineage-negative CD34+ CD38?. However, murine hematopoietic stem cells were reported to be CD34?. We have characterized the surface phenotypes of murine hematopoietic stem cells by using a murine transplantation model. Our studies revealed that the majority of the stem cells in normal adult mice are CD34? while a minority (15%–20%) being CD34+. Our studies also revealed that stem cells that are activated by injection of 5-fluorouracil in vivo, exposure to cytokines in vitro, or mobilization by G-CSF are CD34+ and that CD34 expression is reversible. It has been reported that fetal murine hematopoietic stem cells are CD34+. Our studies revealed that stem cells of juvenile mice are CD34+ and that the developmental change from CD34+ to CD34? state takes place between 7 and 10 weeks of age. In adult mice, expression of CD38 by steady-state and activated stem cells was completely reciprocal of CD34 expression. Activated stem cells and the minority population of the stem cells in the normal mice are CD34+ CD38?. In contrast, the majority of stem cells in normal adult mice are CD34- CD38+. Recently, we studied CD38 expression by stem cells of neonatal and juvenile mice. Stem cells of newborn mice are CD38?. About half of the stem cells of 5-week-old mice are CD38+. Finally, our studies indicated that some of the CD34+ stem cells in the bone marrow of normal adult mice express lineage markers such as Mac-1 and CD4. These studies in a murine model clearly documented that expression of both CD34 and CD38 by stem cells is under developmental control and may be subject to changes induced by activation of the stem cells. In order to test whether or not these principles apply to human stem cells we tested surface phenotypes of human stem cells using two xenotransplantation techniques. Studies based on human/sheep xenograft model indicated that a significant portion of adult human long-term engrafting cells are CD34?. Similar to mouse stem cells expression of CD34 by human stem cells was reversible. Studies based on our newborn NOD/SCID/β-microglobulinnull mice indicated that human cord blood stem cells are CD34+ CD38?. These results appear to support the validity of studies of murine stem cells to provide insight into human stem cells. 相似文献
75.
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder characterized by progressive motor paralysis and selective motor neuron death. There is increasing evidence that motor neuron death in ALS is mediated by glutamate toxicity resulting from reduced activity of astrocytic glutamate transporter‐1 (GLT‐1). Recent morphological studies have shown that N?‐(carboxymethyl)lysine (CML) accumulates in reactive astrocytes of ALS spinal cords. CML is a product of post‐translational protein modification by glyoxal, a reactive aldehydic intermediate. In considering these documents, it is important to determine whether GLT‐1 protein modification by glyoxal might cause reduced GLT‐1 activity. To address this issue, we investigated the effects of glyoxal on GLT‐1 properties in cultured rat astrocytes. High performance liquid chromatography showed reduced glutamate uptake activity in the glyoxal‐exposed cells. Immunocytochemical analysis displayed CML accumulation in the cytoplasm of astrocytes by glyoxal exposure. Immunoblots of immunoprecipitated GLT‐1 disclosed GLT‐1 CML adduct formation in the glyoxal‐exposed cells. Our results indicate that glyoxal modifies GLT‐1 to form CML and simultaneously deprives its glutamate uptake activity. Thus, these toxic effects of glyoxal on astrocytes might be implicated in motor neuron death in ALS. 相似文献
76.
To evaluate the quality of various grading systems for lymph node invasion in cancer of the thoracic esophagus, the surgical results of 142 patients who underwent systematic lymph node dissection with curative intent were analyzed. The survival probability of patients in the same grade was modeled using a Weibull distribution and the parameters were estimated by the maximum likelihood principle. The quality of each grading system was measured by the Akaike Information Criterion (AIC) of the estimated statistical model, by which the smaller the AIC of a grading system, the smaller the loss of information for predicting outcomes. The AIC of the TNM grading of the International Union Against Cancer, the grading of the Japanese Society for Esophageal Diseases, and the grading designed according to the total number of positive lymph nodes became substantially smaller in that order. The AIC of grading systems variously designed on rather simple criteria were examined with the aim of creating a better grading system. It was concluded that a grading system based on the total number of positive nodes and the state of the paratracheal and/or middle mediastinal node groups was better than the other systems examined. 相似文献
77.
BACKGROUND: Chronic colitis-harboring TCRalpha(- / - ) x AIM(- / - ) mice showed PBC-like bile duct damage in the liver. Bacterial infection is one of the candidates for the pathogenesis of PBC. We demonstrated that the bacterial cell wall component lipotheicoic acid (LTA) was detected at sites of inflammation around damaged bile ducts in PBC patients. The aim of this study was to investigate the pathophysiology of the liver and other organs in TCRalpha(- / - ) x AIM(- / - ) mice. METHODS: Thirteen female TCRalpha(- / - ) x AIM(- / - ) mice were sacrificed at 24 weeks of age. The liver, stomach, small intestine, colon, pancreas, kidney and spleen were studied for pathological examination. Using anti-LTA antibody as the primary antibody, an immunohistochemical study was carried out. RESULTS: In the liver, LTA was mainly detected in the portal area with inflammation, and some of the cytoplasm of hepatocytes. Inflammations were also observed in the stomach, intestine, pancreas and kidney. Throughout the gastrointestinal tract, from the stomach to the colon, LTA was detected in the epithelium at sites of inflammation. Furthermore, LTA was detected around both pancreatic ducts with inflammation and distal renal tubules with inflammation. CONCLUSIONS: The development of inflammations in the liver as well as extensive organs, strongly suggests a close relationship between bile duct damage and systemic multifocal epithelial inflammations, perhaps involving bacterial LTA, in TCRalpha(- / - ) x AIM(- / - ) mice. 相似文献
78.
79.
Matsukawa H Kanai T Naganuma M Kamada N Hisamatsu T Takaishi H Ogata H Mukai M Ishii H Mimori T Watanabe M Hibi T 《Journal of gastroenterology》2005,40(10):945-955
Background Apoptosis is a crucial element in the behavior of mammalian cells in many different situations. We here report the establishment
of a novel monoclonal antibody (anti-LHK mAb) that has apoptosis-inducing activity against colon cancer Colo205 cells.
Methods The mechanism of anti-LHK mAb-induced cell death was assessed by microscopic morphology, Annexin V/Hoechst 33528 staining,
and detection of DNA fragmentation. The molecular weight of LHK antigen was determined by Western blotting. Growth inhibition
of Colo205 cells induced by anti-LHK mAb was determined by in vitro and in vivo studies.
Results Anti-LHK reacted with a 70-kDa antigen and completely blocked the proliferation of Colo205 cells bearing LHK in vitro in a
manner characteristic of apoptosis. Strikingly, anti-LHK mAb suppressed tumor growth in a murine peritoneal dissemination
model.
Conclusions LHK antigen, which is restricted to epithelial cells, may be a novel death receptor that plays a critical role in controlling
the growth, invasion, and metastasis of human colon cancer cells. 相似文献
80.
Dysregulation of granulocyte, erythrocyte, and NK cell lineages in Fli-1 gene-targeted mice
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Masuya M Moussa O Abe T Deguchi T Higuchi T Ebihara Y Spyropoulos DD Watson DK Ogawa M 《Blood》2005,105(1):95-102
Targeted disruption of the Friend leukemia integration 1 (Fli-1) proto-oncogene results in severe dysmegakaryopoiesis and embryonic lethality. We used morula-stage aggregation as a strategy to further clarify the hematopoietic defects of the Fli-1 gene-targeted mice. Analyses of lineage expression of Fli-1(+/-) and Fli-1(-/-) cells in the peripheral blood and bone marrow of chimeric mice consistently demonstrated reduced numbers of neutrophilic granulocytes and monocytes and increased numbers of natural killer (NK) cells. Transplantation studies using sorted Fli-1 mutant cells produced similar findings. Clonal culture studies of bone marrow cells revealed increased numbers of granulocytic and early erythroid progenitors in the Fli-1(+/-) cells. The sorted Fli-1(-/-) bone marrow cells revealed specific down-regulation of CCAAT/enhancer binding protein-alpha (C/EBPalpha) and C/EBPepsilon, and the receptors for granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage CSF (GM-CSF), consistent with their critical roles in granulopoiesis. Collectively, these observations suggest previously unknown physiologic roles for Fli-1 in granulocytic, erythroid, and NK cell proliferation and differentiation. Production of chimeras by morula-stage embryo aggregation is an effective way to unravel cell-autonomous hematopoietic defects in gene-targeted mice. 相似文献