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1.
A new doxorubicin analogue, epirubicin (EPI), was evaluated in 41 patients with acute leukemia at 11 Japanese institutions participating in a phase II study between January 1983 and July 1985; during this period 35 patients were considered evaluable. There were 25 males and 10 females with a median age of 43 years (range, 19-71 years) and the median PS of 2 (range, 0-4). EPI was given to 25 patients who had previously been treated with intensive combination chemotherapy, of whom 22 had already received anthracyclines. Ten patients had not been treated previously. Two dose schedules were explored. The higher dose schedule (18 cases) consisted of the administration of 24 to 60 mg/m2 for 3 to 5 consecutive days, and the lower dose schedule (17 cases) consisted of 11 to 20 mg/m2 for 5 to 7 days. Remissions were obtained in 7 patients (20%), 2 of whom showed complete remission and 5 partial remission. The remission duration was 2, 2, 3, 5, 16, 16 and 29+ weeks, respectively. The expected myelosuppression was universal. Stomatitis occurred in 15 patients, of which 7 cases were severe. This stomatitis occurred frequently in the higher dose schedule, and was thought to be a dose-limiting factor. In others, alopecia, G.I. symptoms, and diarrhoea (4 patients) were seen. These results from a cooperative group study indicated that EPI was an effective drug for the treatment of acute leukemia.  相似文献   
2.
Expression of six proto-oncogenes (fos, myc, myb, Ki-ras, Ha-ras, and N- ras) in 43 cases of non-Hodgkin's lymphoma was analyzed by means of in situ hybridization. Biotinylated DNA probes of the six oncogenes and those of immunoglobulin H (IgH) gene and T-cell receptor beta (TCR beta) chain gene were used. The results of in situ hybridization performed under blind conditions by IgH gene and TCR beta chain gene probes were compatible with those of typing by cell surface markers. The nuclear protein-related proto-oncogenes, fos, myc, and myb, were expressed in about 70% to 80% of all cases regardless of phenotype, histology, or histologic grade. On the contrary, genes of ras family were expressed in more limited numbers of cases except for the Ki-ras gene, which was more frequently expressed by cases of the T-cell immunophenotype with a high malignancy grade. The results of dot hybridization with RNA extracted from some cases were compatible with those of in situ hybridization, further demonstrating the specificity of in situ hybridization.  相似文献   
3.
A 48-year-old man presented with malignant hypertension and massive proteinuria. Renal angiography showed complete obstruction of the left renal artery and 99mTc-mercaptoacetylglycine (MAG3) renography showed a nonfunctioning left kidney. Percutaneous transluminal renal angioplasty of the left renal artery was unsuccessful; hence, the patient underwent left nephrectomy because of uncontrolled hypertension and proteinuria. Histological examination of a right kidney specimen revealed lesions of focal segmental glomerulosclerosis with benign nephrosclerosis. In contrast, histology of the left kidney showed typical ischemic kidney with hypertrophy of arteriolar smooth muscle cells. The patient responded favorably to the nephrectomy, as his blood pressure and urinary protein dramatically decreased with no antihypertensive medication. This case illustrates the heterogeneous effect of the renin-angiotensin system on either kidney in patients with renovascular hypertension due to unilateral renal artery stenosis.  相似文献   
4.
Using differential radiation sensitivity of components of mouse embryonal thymus, an in vitro method for studying T-cell differentiation from hemopoietic stem cells (HSCs) in the G0 phase was established. Intrathymic T-cell precursors present in embryonal thymus were found to be quite radioresistant (up to 20 Gy), and consequently 25-Gy-irradiated embryonal thymic lobes were used. Thymic lobes (25-Gy irradiated) taken from mouse fetuses (gestation day 15) were placed in Millipore-HA culture plates supported on squares of gelatin foam sponge in 24-well culture plates in which neonatal thymus stromal cells were cultured. HSCs (10(5) cells per well) in the G0 phase were added to these thymic lobes and cocultured at 37 degrees C in a 5% CO2/95% air incubator. Half the culture medium was changed every week. After 3 weeks, a large number of colonies had formed. Immunohistochemical studies and fluorescence-activated cell sorter analyses revealed that the colonizing cells regularly develop and exhibit surface markers characteristic of T cells (Thy-1, IL-2R, L3T4, Lyt-2, etc.). In situ hybridization analyses revealed that mRNA expression for T-cell receptor (TCR) beta chains occurred within colonizing cells. Using a monoclonal antibody (F23.1), expression of TCR beta-chain variable domain (V beta 8) on the surface of these developing T cells was demonstrated. These cells responded to interleukin 2 and/or anti-CD3 monoclonal antibody, indicating functional T cells. This method will be useful in studying T-cell differentiation pathways from pluripotent HSCs and in clarifying the mechanisms involved in negative and positive selection of T cells within the thymus.  相似文献   
5.
A novel glutathione-conjugated metabolite of morphine has been isolated from the bile of guinea pigs given morphine. The metabolite was separated by preparative HPLC on a reverse phase column (YMC-GEL C18) using methanol/water (1:4, v/v) as eluate and purified by HPLC on another reverse phase column (mu-Bondapak phenyl) using water/acetonitrile/trimethylamine/acetic acid (150:3:2:1, v/v) as a mobile phase. The unambiguous structure assignment of the metabolite was performed by fast atom bombardment mass spectrometry and 400 MHz fourier transform NMR spectrometric analysis, and it was identified as (8S)-glutathion-S-yl)dihydromorphinone, in comparison with the synthetic morphinone-glutathione adduct.  相似文献   
6.
7.
To elucidate the mechanisms of metastasis, we established two sublines HPC-1H5 with a highly liver metastatic cell line and HPC-1P5a with a highly peritoneal disseminating cell line, which were sequentially selected from the parental pancreatic cancer cell line HPC-1. Using these three cell lines, we investigated several biological properties and mRNA levels of differentially-expressed genes involved in cancer metastasis by cDNA macroarray. Microscopic findings for the three cell lines were the same. The tumorigenicity, in vitro growth ability, motile activity, adhesive activity and the production of IL-8 of metastatic sublines were higher than those of parental HPC-1 cells. Particularly, HPC-1H5 cells showed clearly higher levels of IL-8 expression and tumors of HPC-1H5 cells grew faster and bigger than those of HPC-1P5a cells. In cDNA macroarray analysis of HPC-1H5 cells, 22 genes were up-regulated and 44 genes were down-regulated compared with parental HPC-1 cells. In HPC-1P5a cells, 9 genes were up-regulated and 28 genes were down-regulated compared with parental HPC-1 cells. This study provides a demonstration of global gene expression analysis of pancreatic cancer cells with liver metastasis and peritoneal dissemination. Furthermore, our results provide a new insight into the study of liver metastasis and peritoneal dissemination of human pancreatic cancer. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
8.
It is well known that dendritic cells (DCs) are developed from the peripheral blood of mice when peripheral blood mononuclear cells (PBMCs) are cultured with GM-CSF. We have previously found that immature DCs are present in the blood even in humans. In the present study, we show that CD11c+ CD3- B220- cells in the mouse peripheral blood are immature DCs. The percentage of CD11c+ CD3- B220- cells in the (PBMCs) of normal mice ranges from 0.5 to 2.5%. The CD11c+ CD3- B220- cells in the PBMCs show dendrites, similar in shape to the CD11c+ CD3- B220- cells in the spleen, which are thought to be DCs definitely. However, they have practically no capacity to stimulate the proliferation of allogeneic T cells, and show a lower expression of MHC class II, B7-1 and B7-2 than CD11c+ CD3- B220- cells in the spleen. When the CD11c+ CD3- B220- cells in the PBMCs are cultured with GM-CSF, they show not only the potent ability to stimulate the proliferation of allogeneic T cells but also a higher expression of MHC class II, B7-1 and B7-2. Moreover, they migrate into the spleen when they are injected intravenously. These results suggest that CD11c+ CD3- B220- cells in the PBMCs are immature DCs, and that they migrate into the spleen, where they mature.  相似文献   
9.
Structural changes in the developing rat lung were studied by a combined use of light microscopy including immunohistochemistry for a-smooth muscle actin (alpha-SMA) and scanning electron microscopy (SEM) using the KOH-collagenase digestion method. In the embryonic stage (E11-E13), the lung bud appeared as an outgrowth from the ventral wall of the foregut which grew caudally into the splanchnic mesoderm to form a pair of bronchial buds at the end. At E13, the airway smooth muscle cells first appeared around the bifurcation of the trachea. These smooth muscle cells were restricted to the dorsal surface of the tracheal epithelium, suggesting a difference in character between the dorsal and ventral sides of the mesenchymal cells in this region. During the pseudoglandular stage (E13-E18.5), the bronchial buds repeatedly gave off branches in the mesenchymal tissue. The smooth muscle cells in the bronchioles were spindle-shaped and arranged completely circularly around the epithelial tube, except that the terminal bud of bronchioles lacked the smooth muscles. The neck of the terminal bud was constantly surrounded by flat and irregularly-shaped immature smooth muscle cells, representing an early event in the smooth muscle cell differentiation from mesenchymal cells. In the canalicular to saccular stages (E18.5 to birth), the terminals of bronchioles became saccular, thus forming prospective alveolar acini. At birth, the alveolar wall became thinner than before birth, and the individual smooth muscle cells in bronchioles were elongated like a tape. As to the blood vessel differentiation, various sized sinusoidal spaces indicating the primitive blood vessels were already present in the mesenchymal tissue at E11.5. The endothelial cells of these sinusoidal spaces were irregularly shaped and sometimes extended their processes into the lumen. The network of tubular vessels appeared from E14.5. These vessels had tapering ends as well as transluminal trabeculae, suggesting that capillary growth proceeds by both the sprouting and partitioning (i.e., intussusception) of vessels in the pseudoglandular stage.  相似文献   
10.
We report and discuss a case of Kimura's disease with an unusual eosinophilic epithelioid granulomatous reaction. A 3-year-old Japanese boy with eosinophilia and a high concentration of IgE developed lymphadenopathy and multiple cervical masses. A lymph node biopsy demonstrated the infiltration of eosinophils in the stroma, which is consistent with the findings of Kimura's disease. Interestingly, a number of apoptotic eosinophils was detected in the infiltrating eosinophils. Multiple epithelioid granulomas with central eosinophilic abscesses and necrosis were also observed. Macrophages and giant cells had phagocytosed the apoptotic eosinophils at the edge of the granulomas. In situ terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) assay showed that the TUNEL-positive eosinophils were both in the macrophages and in the central eosinophilic abscesses of the granulomas. These findings suggest that the eosinophils had undergone an accelerated apoptosis in this case of Kimura's disease, and that the epithelioid granulomas were produced by phagocytosis of the apoptotic eosinophils by macrophages.  相似文献   
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