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1.
Many asthmatic children have experienced atopic dermatitis in their younger days. As it is very difficult to cure childhood asthma we attempted to determine the anti-allergic drug effects in preventing the development of asthma by using ketotifen on atopic dermatitis patients. The study was designed as a placebo controlled double blind trial of 128 atopic dermatitis patients aged from 2-34 months. 91 patients were given complete analysis in the study, 33 patients were given only a safety rate and 4 patients were dropped. The 91 patients were followed for 52 weeks. Our primary finding was that the development of bronchial asthma was inhibited in the ketotifen group compared to the placebo controlled group with a statistically significant degree (p less than 0.001). We also found that clinical symptoms of atopic dermatitis were significantly improved in the ketotifen group (p less than 0.001). Only 5 patients complained of mild side effects.  相似文献   
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Ectopic hormone production is very rare in hematological malignancy. Here, we describe an interesting case of acute lymphoblastic leukemia (ALL) with adrenocorticotropic hormone (ACTH) production. A 47-year-old man was admitted to our hospital with a 7-month history of hyperpigmentation. The plasma level of ACTH was markedly elevated without a circadian rhythm and the level of cortisol was normal. Examination of bone marrow aspiration revealed ALL, and no other disease as a cause of the elevated ACTH was detected. Sephadex G-75 chromatography of plasma ACTH extract revealed the existence of an abnormally large molecular ACTH (probably proopiomelanocortin) in addition to authentic 1-39 ACTH. Ectopic ACTH of low biological activity is considered to be the reason for a discrepancy in the plasma levels of ACTH and cortisol. Shortly after remission induction chemotherapy, blast cells in the peripheral blood disappeared, and the plasma level of ACTH became normal, leading to an improvement of skin pigmentation. These clinical findings and laboratory data suggested that leukemia cells in this case may produce the ACTH.  相似文献   
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Purpose. For tumor growth, proteolytic remodeling of the extracellular matrix (ECM) is a key factor. To determine proteolytic activity in human glioma cells, fibrinolytic activity, mRNA expression of fibrinolytic factors, and fibrinolytic inhibitors were studied in human glioma cell lines. The effect of platelet activating factor (PAF), a potent mediator of inflammatory and immune responses, on this fibrinolytic activity was also examined. Methods. The fibrinolytic activities of conditioned medium and cell lysates from human glioma cell lines, A172, T98G, U87 and TM1 were studied by fibrin plate zymography. mRNA expression of tissue plasminogen activator (tPA), urokinase-type plasminogen activator (uPA) and plasminogen activator inhibitors (PAI-1, PAI-2) was measured by Northern blot analysis. PAF was added to the medium, and its effects on cell proliferation, fibrinolytic activity, mRNA expression of plasminogens and inhibitors were studied. Results. mRNA expression of plasminogens and inhibitors differed between individual cell lines. Only the medium and cell lysates from A172 cells revealed fibrinolytic activity. A172 cells showed mRNA expression of tPA. PAF at low concentrations, such as 1 nM, stimulated A172 cell proliferation, and high concentrations of PAF inhibited proliferation. PAF stimulated tPA release into the conditioned medium. mRNA expression of tPA was stimulated by low concentrations of PAF and inhibited by high concentrations. Conclusion. The variability of mRNA expression of plasminogen activators (PAs) between different glioma cell lines may indicate that plasminogens and their inhibitors do not directly correlate with brain tumor growth. PAF may be an important factor in the local control of fibrinolytic activity in glioma and its proliferation.  相似文献   
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Although CD4(+) helper T lymphocytes have been demonstrated to play an important role in antitumor immune response, only a few epitopes of tumor-associated antigens recognized by HLA class II-restricted CD4(+) T lymphocytes have been identified. In the present study, we addressed the question of whether leukemia-associated fusion proteins are recognized by CD4(+) T lymphocytes. Immature dendritic cells (DCs) were loaded with necrotic or apoptotic leukemia cells with t(6;9) or t(9;22) and then cocultured with the dek-can fusion peptide-specific or the bcr-abl fusion peptide-specific CD4(+) T lymphocyte clone. The dek-can peptide-specific and bcr-abl peptide-specific CD4(+) T lymphocyte clones produced interferon-gamma (IFN-gamma) when they were cocultured with HLA-DR-matched but not with mismatched DCs which had been loaded with apoptotic as well as necrotic leukemia cells with t(6;9) and t(9;22), respectively. IFN-gamma production by CD4(+)T lymphocyte clones in response to stimulation with DCs loaded with leukemia cells was inhibited by the anti-HLA-DR monoclonal antibody. These data indicate that the acute myelogenous leukemia-associated fusion protein, dek-can, and chronic myelogenous leukemia-associated fusion protein, bcr-abl, are both processed and presented by DCs to the fusion peptide-specific CD4(+) T lymphocytes.  相似文献   
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Encapsulated hepatocyte transplantation is a promising approach to cell transplantation without immunosuppression as an alternative to whole organ liver transplantation. However, the shortage of donor cells for hepatocyte transplantation has not been resolved, and at this critical point, it seems necessary to establish a method of hepatocyte cryopreservation to allow clinical application of hepatocyte transplantation and the development of a bioartificial liver system in the near future. In this study we demonstrated that cryopreserved microencapsulated rat and human hepatocytes can retain their hepatic function and that cryopreserved microencapsulated human hepatocytes transplanted into rat spleen remain viable without immunosuppression. Rat and human hepatocytes were isolated by a collagenase digestion method, and they were microencapsulated with poly-L-lysine. The microencapsulated rat hepatocytes were transferred to culture medium (DMEM containing 10% FBS and 10% DMSO) and immediately frozen in liquid nitrogen. A warm water bath (37 degrees C) was used to thaw the microencapsulated hepatocytes. Hepatic function, drug metabolism, and cell morphology were assessed after 90 days of cryopreservation. After 1 week of cryopreservation, microencapsulated hepatocytes were cultured for up to 2 weeks to assess their hepatic function and morphology. The morphology of human hepatocytes was assessed after 30 days of cryopreservation. Cryopreserved human hepatocytes were transplanted into rat spleen to assess their morphology. Cryopreserved microencapsulated hepatocytes retained their viability and were strongly positive for expression of albumin, OAT2, CYP3A2, and CYP3A9. Two weeks after cultivation, the cryopreserved microencapsulated rat hepatocytes had retained their hepatic function (urea synthesis). Cryopreserved microencapsulated human hepatocytes also mainly survived and retained their hepatic function for at least 30 days after cryopreservation. Moreover, entrapped cryopreserved human hepatocytes also survived and expressed albumin in rat spleen after transplantation. We demonstrated a novel method of long-term cryopreservation of rat and human hepatocytes by using an encapsulation technique, with retention of biological activity and excellent survival of the cryopreserved microencapsulated human hepatocytes transplanted into rat spleen. We believe that this novel approach to hepatocytes cryopreservation provides a new direction in encapsulated cell therapy with the goal of clinical application in the near future.  相似文献   
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The incidence of hepatic venous complications in partial liver transplantation is more frequent than that in whole liver transplantation. There are no reports of a surgical strategy for hepatic venous outflow block (HVOB) after living-donor liver transplantation. HVOB was diagnosed when the pull-through pressure gradient across the anastomotic site was over 5 mm Hg. Reoperation for venous anastomosis was performed if the angioplasty was unsuccessful. After dissection around the hepatic venous anastomotic site, a patch venoplasty of the anastomosis was performed. When the inferior vena cava was constricted, venoatrial anastomosis was performed. In 6 years, 5 of 223 patients experienced HVOB. Balloon angioplasty was successfully performed in two patients, a patch venoplasty of the anastomosis in two, and venoatrial anastomosis in one. In all patients, the ascites stopped. HVOB must be diagnosed as soon as possible with Doppler ultrasound and venography. Prompt surgical revision can salvage the grafts.  相似文献   
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Purpose We have previously demonstrated doxorubicin-induced urokinase (uPA) and interleukin-8 (IL-8) expression in human H69 small-cell lung carcinoma (SCLC) cells by a microarray technique using Human Cancer Chip version 2, in which 425 human "cancer-related" genes are spotted on the plates. The microarray analysis also revealed a significant induction of tumor necrosis factor-alpha (TNF-), and doxorubicin-induced macrophage chemoattractant protein-1 (MCP-1) expression was demonstrated by an RNase protection assay. We extended the study by testing the effects of doxorubicin on the induction of TNF-, uPA, IL-8 and MCP-1 in other types of lung carcinoma cells.Methods We investigated the effects of doxorubicin on the expression of TNF-, uPA, IL-8 and MCP-1 in 12 human lung carcinoma cell lines, including five SCLC, three adenocarcinoma and four squamous cell carcinoma cells. The surface expression of their receptors was also investigated.Results TNF- was significantly induced in three cell lines, H69, SBC-7 (SCLC) and PC-9 (adenocarcinoma), uPA in five cell lines, H69, SBC-7, EBC-1 (squamous cell), EBC-2 (squamous cell), and Sq-1 (squamous cell), IL-8 in three cell lines, H69, PC-9 and EBC-1, and MCP-1 in five cell lines, H69, SBC-3 (SCLC), SBC-7, PC-9 and Sq-1. In H69 cells, TNF- antigen levels were increased approximately fivefold in the conditioned medium of doxorubicin-treated cells, in parallel with an increase in mRNA levels. As with uPA and IL-8, the maximum induction was observed at the "sublethal" concentrations of 2 and 4 M at which cell growth was slightly inhibited 24 h after treatment. Furthermore, the cells did not express receptors including types I and II TNF- receptors, uPA receptor (uPAR), C-x-C-chemokine receptor-1 (CXCR-1), or C-C-chemokine receptor-2, corresponding to TNF-, uPA, IL-8 and MCP-1, respectively, that were induced by doxorubicin in the cells, although SBC-7 cells expressed uPAR, and EBC-1 cells expressed CXCR-1.Conclusions TNF-, uPA, IL-8 and MCP-1 induced and secreted from tumor cells upon doxorubicin stimulation may activate surrounding cells expressing the receptors such as neutrophils and monocytes/macrophages in a paracrine fashion. TNF- is a major proinflammatory cytokine, and IL-8 and MCP-1 are major chemoattractants for neutrophils and monocytes/macrophages, respectively. Furthermore, uPA activates matrix metalloproteinase 9 which can truncate and activate IL-8. Thus, the simultaneous induction of TNF-, uPA, IL-8 and MCP-1 may enhance the interaction between tumor and inflammatory/immune cells, and augment cytotoxicity.Abbreviations BSA Bovine serum albumin - C-C Cysteine-cysteine - C-x-C Cysteine-x-cysteine - CCR-2 C-C chemokine receptor-2 - CXCR-1 C-x-C chemokine receptor-1 - ELISA Enzyme-linked immunosorbent assay - IL-1 Interleukin-1 - IL-6 Interleukin-6 - IL-8 Interleukin-8 - MCP-1 Macrophage chemoattractant protein-1 - MTT (3-(4,5-dimethylthiazol-2-yl)2,5-diphenyl tetrazolium bromide - PBS Phosphate-buffered saline - ROS Reactive oxygen species - SCLC Small-cell lung cancer - TNF- Tumor necrosis factor-alpha - TNFRI Type I tumor necrosis factor-alpha receptor - TNFRII Type II tumor necrosis factor-alpha receptor - uPA Urokinase-type plasminogen activator - uPAR Urokinase-type plasminogen activator receptor  相似文献   
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