• Tuberculosis and Respiratory Diseases
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• v.64 no.1
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• pp.22-27
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• 2008

Background: Staphylococcus aureus frequently colonizes and infects hospitalized patients. Respiratory infections with Staphylococcus aureus are common in patients with compromised airway defenses. However the mechanisms of S. aureus invasion from colonization to the epithelium are unclear. Cell invasion by S. aureus would require destruction of the extracellular matrix, which is believed to be the result of increased matrix metalloproteinases (MMP) activity. Methods: In this study, respiratory epithelial cells were infected with S. aureus. After removing the extracellular bacteria by washing, the internalized bacteria in the cells were assessed by counting the colonized forming units (CFUs). The cell adhesion proteins, dysadherin and E-cadherin, were evaluated by Western blotting. The MMPs in the bacterial invasion were evaluated by pretreating the cells with GM6001, a MMP inhibitor. Results: The internalization of S. aureus was found to be both time and dose dependent, and the increase in MMP 2 and 9 activity was also dependent on the incubation time and the initial amount of bacterial inoculation. The invasion of S. aureus was attenuated by GM6001 after 12 hours incubation with a multiply of infection (MOI)=50. The expression of dysadherin, a membrane protein, was increased in a time and dose dependent manner, while the expression of E-cadherin was decreased. Conclusion: MMPs may mediate the invasion of S. aureus into epithelial cells.

• Journal of Chest Surgery
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• v.30 no.6
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• pp.559-565
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• 1997

Donor airway ischemia is a significant problem after tracheal replacement with homograft or lung transplantation, Several factors such as omentopexy, heparin, PGl2 and fibroblast growth factor, have been shown to induce angiogenesis in vitro and in vivo. This study was designed to investigate whether omentopexy and basic flbroblast growth factor can enhance rabbit tracheal revascularization and epithelial regeneration, Three different experiments were performed with New Zealand white rabbit. In group I(n= 15 control group), only coNical tracheal autotransplantation was done. In group II(n= 15), cervical tracheal autotransplantation with omentopexy was done through subcutaneous route. In group III(n= 15), cervical tracheal autotransplantation was done and lug basic flbroblast growth factor was applied. After 3, 7 and 14 days, the animals were sacrificed. The extent of revascularization was investigated by means of uptake of the human serum albumin labelled with 99m technetium, and epithelial regeneration were assessed by means of light microscope. In the group investigated at day 3, there was statistically significant high tracheal revascularization in group III(p<0.05), but no difference at 7 and 14 days. And epithelial regenerations at day 3 were better in group III(p<0.05), and at day 7 in group II and III. But there was no difference at day 14. We concluded that b-FGF can enhance the revascularization and epithelial regeneration of the tracheal autograft especially in early phase.

• Journal of Chest Surgery
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• v.32 no.3
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• pp.215-223
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• 1999

Background: The replacement of the narrowed long-segment trachea with various prosthetic materials or tissue grafts remains a difficult and unsolved surgical problem. Homologous cryopreserved tracheal transplantation has been considered to treat the irreversibly-damaged organs, such as in the lung or heart transplantation and also to overcome the limited supply of donor organs. We examined the morphological changes and the immunosuppressive effects of the cryopreserved trachea after the heterotopic transplantation in the rats. Material and Method: Sixty tracheal segments harvested from 30 donor Wistar rats were heterotopically implanted into the peritoneal cavity of 20 recipient Wistar rats and 40 Sprague Dawley rats. The 60 recipient rats were divided into 6 groups(10 rats/ group). In groups I, II, and III, 30 tracheal segments were implanted immediately after the harvesting and in groups IV, V, and VI, the segments were implanted 28 days after the cryopreservation. Groups I and IV were Wistar syngeneic controls. Groups II and V were Sprague Dawley recipients receiving no immunosuppression and Groups III and VI, were Sprague Dawley recipients receiving immunosuppressive agents. At 28 days all rats were sacrificed and the tracheal segments were evaluated grossly and histologically. Result: Immunosuppression of the tracheal segments had a significant influence on the changes of the tracheal lumen and tracheal epithelial cells, irrespective of the cryopreservation of the trachea(p<0.001). In groups III and VI receiving immunosuppressive agents, the tracheal lumen was patent and the normal epithelial cells were observed, however in the other groups not receiving the immunosuppressive agents, there were almost luminal obliteration by the proliferation of the fibrous tissues and a loss of the epithelial cells, the findings were similar to those in the case of obliterative bronchiolitis after a lung and a heart-lung transplantation. Conclusion: With the appropriate immunosuppressive agents, the lumen and the respiratory epithelium of the transplanted tracheal segment were well preserved, even after the cryopreservation of the tracheal segment, which shows the possibility of the long-term preservation and homologous transplantation of the trachea. But fibroproliferative obliteration of the tracheal lumen and the loss of the normal respiratory epithelial cells, characteristic findings of obliterative bronchiolitis, were observed in the groups without the immunosuppression. This experiment using the rat trachea may be useful in studying the pathogenesis, treatment, and prevention of obliterative bronchiolitis after a lung and a heart-lung transplantation.

• Tuberculosis and Respiratory Diseases
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• v.46 no.4
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• pp.523-532
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• 1999

Background: With the development of the molecular biological methods, studies of the early diagnosis of lung cancer and the detection in the preneoplastic state by using genetic probes in the high risk groups are widely investigated. In lung cancer, squamous cell carcinoma is considered to progress from the normal bronchial mucosa to the preneoplastic state, and finally to the invasive carcinoma. In this study, we investigated the expression of p53 and c-erbB2 in the normal bronchi and the cancer tissues in patients with squamous cell lung cancer to evaluate the possibility of using these immunohistochemical markers as the diagnostic and prognostic parameters of patients with squamous cell lung cancer. Method: The normal and cancerous bronchial tissues of 25 patients with squamous cell carcinoma of the lung, surgically resected from May 1995 to November 1996, were immunohistochemically stained with the monoclonal antibodies to p53(DAKO-p53) and c-erbB2(phamingen 15821A) respectively. We compared the expression status of these markers between the normal bronchial mucosa and the tumor tissue, and also investigated the relationship between the expression status of these markers in tumor tissues and the pathological stage, and the survival time. Results: The pathological stage was as follows; stage I, II were found in 5 patients respectively, stage IIIA was in 8 patients, stage IIIB was in 4 patients, and stage IV was in 3 patients. The expression rate of p53 in the squamous cell lung cancer was 48%, and it was not expressed in the normal bronchial mucosa. The expression status was increased as the pathological stage advanced(p=0.0091 by test of trend). But there were no relationship between the expression of p53 and the median survival time. C-erbB2 did not yield a significantly meaningful result. Conclusion: p53 was not found in the normal bronchial mucosa, but it was expressed in 48% of the tumor tissue. And the expression rate increased as the pathological stage advanced. So it would be helpful to apply the immunochistochemical stain with p53 in the bronchial biopsy specimen in the early diagnosis trial or staging of squamous cell lung cancer.

• Radiation Oncology Journal
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• v.19 no.2
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• pp.190-198
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• 2001

Purpose : It was reported that Captopril (angiotensin converting enzyme inhibitor) had an effect to reduce the pneumonitis and pulmonary fibrosis induced by radiation in rat. We peformed this study to investigate the radioprotective effect and mechanism of Captopril. Methods and Materials : The comparison was made between the radiation only group and the combined Captopril and radiation group by examining histopathologic findings and immunohistochemical stains $(TNF\alpha\;and\;TGF\beta1)$ at 2 and 8 weeks after irradiation. Each group has 8 to 10 rats (Sprague-Dawley). 12.5 Gy of X-ray was irradiated to the left hemithorax in a single fraction. Captopril (50 mg/kg/d) mixed with water was given per oral and continuously from 1 week prior to irradiation up to 8th week of the experiment. Result : In the combined Captopril and radiation group, the histopathologic changes which were hemorrhage into alveolar space, changes of alveolar epithelium, bronchial epithelium and blood vessels, and perivascular edema were less severe than in the radisation only group at 2 weeks. At 8 weeks, the alveolar epithelial changes and perivascular edema were less prominant in the combined Captopril and radiation group. At 2 weeks, the $TNF\alpha$ expression of the combined Captopril and radiation group was markedly decreased at the alveolar epithelium (p<0.01), lymphoid tissue (p=0.06) and the macrophage of alveolar space (p<0.01) compared with the radiation only group. Furthermore the $TGF\beta1$ expression was significantly prominant at the alveolar epithelium (p<0.02) and the macrophage in alveolar space (p<0.02). At 8 weeks, the expression of $TNF\alpha\;and\;TGF\beta1$ of most sites, except $TGF\beta1$ of the macrophage of alveolar space (p=0.09), showed no significant difference between 2 groups. Conclusion : This study revealed that early lung damage induced by irradiation was reduced with the addition of Captopril in the latent and early pneumonitis phase. The expression of $TNF\alpha\;and\;TGF\beta1$ at 2 weeks and $TGF\beta1$ at 8 weeks was further decreased in the combined Captopril and radiation group than the radiation only group. From these results, it may be concluded that the proinflammatoy cytokine $(TNF\alpha)$ and fibrogenic cytokine $(TGF\beta1)$ probably play the role of the radioprotective mechanism in Captopril.

• Tuberculosis and Respiratory Diseases
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• v.59 no.5
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• pp.530-535
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• 2005

Background and Aims : Cigarette smoking induces an inflammatory response in the airways, which may play a key role in the pathogenesis of chronic obstructive pulmonary disease. Interleukin-6 (IL-6) is one of the cytokines that plays an important role in inducing bronchial inflammation. The aim of this study was to determine if the level of the pro-inflammatory cytokine, Interleukin-6, is increased when the bronchial epithelial cells are exposed to a cigarette smoke extract (CSE) and an extract from stop smoking-aiding cigarettes, and examined the safety of these commercially available stop smoking-aiding cigarettes. Method : Bronchial epithelial cells were exposed to CSE from cigarette and stop smoking-aiding cigarettes for 24 hours. ELISA was used to measure the IL-6 levels in the supernatant from each condition. The IL-6 mRNA levels were measured by Taqman Real time RT-PCR. N-acetyl-L-cysteine(NAC) was added to each condition to determine if NAC can inhibit the release of IL-6 from the bronchial epithelial cells when they are exposed to CSE from cigarette and stop smoking-aiding cigarettes. Result : When bronchial epithelial cells were exposed to a CSE from cigarettes and stop smoking-aiding cigarettes, each type of CSE stimulated IL-6 production from the bronchial epithelial cells. The IL-6 mRNA level in the Bronchial epithelial cells was also elevated and NAC was found to inhibit the release of IL-6 from bronchial epithelial cells when they were exposed to the CSE from cigarettes and stop smoking-aiding cigarettes. Conclusion : Commercially available stop smoking-aiding cigarette can induce bronchial inflammation and can be harmful to smokers. Therefore, the safety of these cigarettes for smoking cessation should be evaluated.

• Tuberculosis and Respiratory Diseases
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• v.63 no.2
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• pp.165-172
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• 2007

Background: The pathogenesis of lung cancer includes the accumulation of multiple genetic abnormalities. The CREB-binding protein(CBP) is one of several transcriptional co-activators among various sequence-specific DNA-binding transcription factors. CBP is involved in a wide range of cellular activities, such as DNA repair, cell growth, differentiation, and apoptosis that are suspected of contributing to tumorigenesis. The goal of this study was to evaluate CBP expression in a series of human lung tissues containing normal epithelium, premalignant lesions(hyperplasia and dysplasia) and squamous cell carcinomas. Materials and Methods: Immunohistochemical staining was performed on formalin-fixed paraffin-embedded sections by use of a monoclonal anti-CBP antibody. CBP expression was compared in samples from 120 patients with premalignant and malignant histological types including 20 metaplastic specimens, 40 dysplastic specimens, and 60 squamous cell carcinomas in the lung. Results: CBP expression was seen in 35% (7/20) of the metaplastic specimens. 65% (26/40) of the dysplastic specimens, and 70% (42/60) of the squamous cell carcinomas (p<0.05). According to celluar atypism, CBP expression was 50% (10/20) of the low-grade dysplastic specimens and 80% (16/20) of the high-grade dysplastic specimens(p <0.01). By cellular differentiation, CBP expression was seen in 95% (19/20) of the well differentiated squamous cell carcinomas, 85% (17/20) of the moderately differentiated carcinomas and 30% (6/20) of the poorly differentiated lesions (p <0.05). Conclusion: These results suggest that CBP may have an important role in malignant transformation of precancerous lung lesions and may be a marker for malignancy.

• Tuberculosis and Respiratory Diseases
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• v.45 no.2
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• pp.311-321
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• 1998

Background: Mucoepidermoid carcinoma of the lung arises from submucosal gland of tracheobronchial tree. Histologically, the tumor is composed of mucin-secreting cells, squamous cells, and intermediated cells, which show no particular differentiating characteristics, in varying proportions. The tumor is divided into low grade and high grade depending on the proportion of cells, and the degree of the mitotic activity, cellular necrosis and nuclear pleomorphism. While favorable prognosis of low grade tumor, high grade tumor, which is very difficult to differentiate from adenosquamous carcinoma, has an aggressive clinical course. The tumor is rare, comprising 0.1 to 0.2% of primary lung cancers and 1 to 5% of bronchial adenomas. Method: A retrospective clinical study was done on 17 cases of mucoepidermoid carcinoma. The study investigated the clinical features, radiologic findings, bronchoscopic findings, histology and clinical courses. Results: Age ranged between second to seventh decade with a mean age of 42 years. Twelve out of 17 cases were male. Five out of 17 cases were smokers with a mean 11 pack-years. Common symptoms included dyspnea, cough, hemoptysis, and wheezing. Two out of 17 cases was asymptomatic. Atelectasis or mass was common radiologic finding. Plain chest radiography was normal in one patient whom the tumor was located in upper trachea. Bonchoscopy revealed exophytic mass in 12 cases and nodular infiltrations in 4 cases. One case having solitary pulmonary nodule in the right lower lung was normal on bronchoscopy. Histologically, ten out of 17 cases were low grade, and seven out of 17 cases were high grade. Among 10 patients with low grade tumor,9 patients were performed operation and have been alive without recurrence during a mean follow-up of 30 months. Two out of 7 patients with high grade tumor were performed pneumonectomy and have been alive during a follow-up of 3 and 8 months, respectively. Conclusion: Most of mucoepidermoid carcinoma is located at central airway and is presented symptoms by mucosal irirtation. Although atelectasis or mass is common radiologic finding. chest X -ray can be normal. The histologic grading and the extent of tumor are two most important factors for prognosis.

• Applied Microscopy
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• v.29 no.3
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• pp.291-301
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• 1999

The differentiation and ultrastructural characteristics of type II pneumocyte was investigated using 7 cases of human fetal lungs from 9 to 20 weeks of gestation by transmission electron micropscopy. The result obtained were as follows. 1. From the pattern of epithelium, type II pneumocyte was not discernable, but with the gradual development of gestation, the epithelium of the future pulmonary alveoli was transformed from pseudostratified columnar into simple cuboidal epithelium after 15 weeks of geatation. 2. The multilamellar body very specific to type II pneumocyte was observed at first at 9 weeks of gestation. Besides, another characteristics of the cell were also observed such as cytoplasmic inclusion body, granular inclusionbody,multivesicularinclusionbodyanddensebody. 3. The number and size of multilamellar body increased, but those of other inclision bodies decreased at 19 and 20 weeks of gestation. In summary, type II pneumocytes (or precursor cells) with multilamellar body and another characteristic inclusion bodies were observed in the human fetal lungs from 9 weeks of gestation. And so, it is suggested that the differentiation of type II pneumocyte starts at or before 9 weeks of gestation.

• Tuberculosis and Respiratory Diseases
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• v.45 no.4
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• pp.835-845
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• 1998

Background: Silica-induced lung diseases is characterized by the accumulation of inflammatory cells at early stage and fibrosis in pulmonary parenchyma and interstitium at late stage. As a consequence of inflammation, silicosis is accompanied with the expansion of interstitial collagen and the formation of fibrotic nodule. In this process, several kinds of lung cells produce cytokines which can amplify and modulate pulmonary fibrosis. The alveolar macrophage is a potent source of proflammatory cytokines and growth factor. But in the process of silicotic inflammation and fibrosis, there are many changes of the kinetics in cytokine network. And the sources of cytokines in each phase are not well known. Method: 2.5 mg of silica was instillated into the lung of C57BL/6J mice. After intratracheal instillation of silica, the lungs were removed for imunohistochemical stain at 1, 2, 7 day, 2, 4, 8, 12 week, respectively. We investigated the expression of IL-1$\beta$, IL-6, TNF-$\alpha$ and TGF-$\beta$ in lung tissue. Results: 1) The expression of IL-6 increased from 1 day after exposure to 8 weeks in vascular endothelium. Also peribronchial area were stained for IL-6 from 7 days and reached the peak level for 4 weeks. 2) The IL-1 $\beta$ was expressed weakly at the alveolar and peribronchial area through 12 weeks. 3) The TNF-$\alpha$ expressed strongly at alveolar and bronchial epithelia during early stage and maintained for 12 weeks. 4) TGF-$\beta$ was expressed strongly at bronchial epithelia and peribronchial area after 1 week and the strongest at 8 weeks. Conclusion: The results above suggests IL-6, TNF-$\alpha$ appear to be a early inflammatory response in silica induced lung fibrosis and TGF-$\beta$ play a major role in the maintenance and modulation of fibrosis in lung tissue. And the regulation of TNF-$\alpha$ production will be a key role in modultion of silica-induced fibrosis.