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The aim of the study was to investigate the expression of basic fibroblast growth factor (bFGF) and its receptor, fibroblast growth factor receptor (FGFR)-1, in the central airways of smokers with chronic bronchitis. The lobar bronchi from 17 subjects undergoing thoracotomy for solitary nodules were examined. All had a history of cigarette smoking, nine had symptoms of chronic bronchitis and airflow limitation, and eight were asymptomatic with normal lung function. Using immunohistochemical methods, bFGF and FGFR-1 expression in the total airway wall and the different airway compartments, i.e. bronchial glands, submucosal vessels and smooth muscle, was quantified. Moreover, to investigate the role of bFGF in angiogenesis, the number of submucosal vessels was quantified. Smokers with chronic bronchitis had an increased bFGF expression in the total airway wall compared with asymptomatic smokers, which was mainly due to bFGF upregulation in bronchial glands. By contrast, the expression of FGFR-1 and the number of submucosal vessels was similar in the two groups of subjects examined. In conclusion, smokers with chronic bronchitis have an increased expression of basic fibroblast growth factor in the central airways, which is mainly due to an increased expression in bronchial glands, suggesting the involvement of this growth factor in the pathogenesis of chronic bronchitis.  相似文献   
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The pleural space is a virtual compartment between the lung and chest wall that becomes filled with fluid and inflammatory cells during a variety of respiratory diseases. Here, we study the potential role of the eicosanoid metabolite leukotriene B4 (LTB4) in disparate diseases leading to acute (pneumonia) or chronic (tuberculosis, cancer) inflammation of the pleural space. LTB4 concentrations were significantly higher in pleural fluid due to pneumonia, tuberculosis and cancer with respect to congestive heart failure and correlated with neutrophil elastase, which is used as an indication of state of activation of neutrophils in the pleural space. Moreover, pleural LTB4 was biologically active, as an anti-LTB4 antibody partially neutralized the chemotactic activity of parapneumonic, tuberculous and cancer effusions. Macrophages, neutrophils, lymphocytes, mesothelial cells and cancer cells all expressed mRNA for 5-lipoxygenase, the enzyme that initiates leukotriene synthesis leading to the production of LTB4, in exudative pleural effusions. Upon stimulation in transudative pleural effusions, pleural macrophages produced, in a time-dependent fashion, a significantly higher concentration of LTB4 than mesothelial cells. These studies demonstrate that different cell types are capable of producing LTB4 in the inflamed pleural space and that this mediator may play a crucial role in the recruitment of neutrophils into the pleural space.  相似文献   
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The inflammatory and remodelling processes that underlie asthma result from a highly complex interaction between various cell types. Apart from inflammatory cells, such as eosinophils, activated T cells, mast cells and macrophages, structural tissue cells such as epithelial cells, fibroblasts and smooth muscle cells can also play an important effector role through the release of a variety of mediators, cytokines and chemokines. This results in an acute inflammatory response that is characterized by vascular leakage, mucus hypersecretion, epithelial shedding and widespread airway narrowing. At the same time, through the release of mediators, cytokines, chemokines and growth factors, epithelial and mesenchymal cells cause persistence of the inflammatory infiltrate and induce structural changes in the airway wall, such as increased thickness of the basement membrane, increased collagen deposition, changes in bronchial microcirculation, and smooth muscle hypertrophy and hyperplasia. The end result of airway inflammation and remodelling is an increased thickness of the airway wall, leading to a reduced baseline airway calibre and exaggerated airway narrowing.  相似文献   
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BACKGROUND: The outcome of patients with nasopharyngeal carcinoma (NPC) presenting as advanced-stage disease or failing conventional radio-chemotherapy is poor. Thus, additional forms of effective, low-toxicity treatment are warranted to improve NPC prognosis. Since NPC is almost universally associated with Epstein-Barr virus (EBV), cellular immunotherapy with EBV-specific cytotoxic T lymphocytes (CTLs) may prove a successful treatment strategy. Patient and methods A patient with relapsed NPC, refractory to conventional treatments, received salvage adoptive immunotherapy with EBV-specific CTLs reactivated ex vivo from a human leukocyte antigen-identical sibling. EBV-specific immunity, as well as T-cell repertoire in the tumor, before and after immunotherapy, was evaluated. RESULTS: CTL transfer was well tolerated, and a temporary stabilization of disease was obtained. Moreover, notwithstanding the short in-vivo duration of allogeneic CTLs, immunotherapy induced a marked increase of endogenous tumor-infiltrating CD8+ T lymphocytes, and a long-term increase of latent membrane protein 2-specific immunity. CONCLUSIONS: Preliminary data obtained in this patient indicate that EBV-specific CTLs are safe, may exert specific killing of NPC tumor cells in vitro, and induce antitumor effect in vivo.  相似文献   
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Several clinical observations have confirmed that a donor immune-mediated anti-malignancy effect, called graft-versus-leukemia or graft-versus-tumor, occurs following allogeneic hematopoietic stem cell transplantation. While the potential antitumor effect mediated by donor lymphocytes has been established in many hematological malignancies, its efficacy in inducing clinically meaningful responses in solid tumors has been largely unexplored despite evidence of its potential benefit in experimental animal models. Only in recent years has the investigational application of non-myeloablative stem cell transplantation in patients with refractory non-hematological cancers proved that a graft-versus-tumor effect can be generated in patients with metastatic renal cell cancer and possibly with other solid tumors. In the present article we review the biological basis, development and early clinical results of this novel immunotherapeutic approach for solid tumors.  相似文献   
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ABSTRACT— Severe coagulation defects, as reflected by platelet count and prothrombin time, have always been considered a contraindication to needle biopsy of the liver, but there are very limited data on the actual rate of bleeding in patients with such severe alterations and none whatsoever on the bleeding risk associated with newer, fine-gauge needles that produce less trauma to the liver tissue. In addition, there has never been any evidence that platelet count and/or prothrombin time are the most sensitive indices of bleeding risk. This retrospective study of 85 patients, with platelet counts less than 50 000/mm3 and/or prothrombin times less than 50% of controls, subjected to ultrasound-guided fine-needle liver punctures for diagnostic or therapeutic (percutaneous ethanol injection) purposes showed no bleeding episodes after any of the 229 punctures performed. No type of replacement therapy was administered to correct clotting defects prior to the procedure. Correct pathologic diagnoses were obtained in 81.2% of all patients. Ultrasound-guided fine needle puncture appears to be safer than currently believed in patients with severe clotting defects and deserves further evaluation as an alternative to surgical procedures to diagnose and treat liver lesions, even when severe coagulation impairment is present.  相似文献   
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Since the early 1980s high dose chemotherapy with autologous hematopoietic stem cell support was adopted by many oncologists as a potentially curative option for solid tumors, supported by a strong rationale from laboratory studies and apparently convincing results of early phase II studies. As a result, the number and size of randomized trials comparing this approach with conventional chemotherapy initiated (and often abandoned before completion) to prove or disprove its value was largely insufficient. In fact, with the possible exception of breast carcinoma, the benefit of a greater escalation of dose of chemotherapy with stem cell support in solid tumors is still unsettled and many oncologists believe that this approach should cease. In this article, we critically review and comment on the data from studies of high dose chemotherapy so far reported in adult patients with small cell lung cancer, ovarian cancer, germ cell tumors and sarcomas.  相似文献   
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