• Tuberculosis and Respiratory Diseases
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• v.41 no.1
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• pp.11-19
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• 1994

Background: Mycobacterium tuberculosis is a facultative intracellular pathogen which persists and multiplies within macrophage. Competent cell mediated immunity by cooperation of both T lymphocyte and macrophage of the host is required to kill the Mycobacterium tuberculosis. But a precise understanding of the pathogenesis of tuberculosis infection in pulmonary alveolar macrophage has not been achived. Research on the macrophage's basic microbicidal mechanism has elucidated the importance of oxygen-dependent or oxygen-independent components. Oxygen dependent processing begins with the reduction of oxygen by NADPH oxidase and generation of superoxide. In this study, the oxidative metabolic status of blood monocyte and pulmonary alveolar macrophage in patients with active pulmonary tuberculosis was accessed and compared with that of healthy control subjects to know whether there was a basic difference in superoxide generation by mononuclear cells between two groups. Methods: Pulmonary alveolar macrophage was purified after performing BAL(bronchoalveolar lavage) through the bronchi of infected lesion by plastic adhesion method. Blood monocyte was purified by Ficoll-Hypaque method. Superoxide generation by blood monocyte and pulmonary alveolar macrophage was measured by ferricytochrome-C reduction method after either stimulated with PMA(phorbol myristate acerate) or non-stimulated states. We also measured the effect of pulmonary tuberculosis patient's serum on superoxide generation by monocyte. Results: 1) Generation of superoxide by alveolar macrophage obtained from patients with pulmonary tuberculosis was little higher than those of controls, and PMA enhanced the generation of 2) Generation of superoxide by blood monocyte obtained from patients with pulmonary tuberculosis was little higher than those of control(p>0.05), and PMA more enhanced the generation of superoxide in patientswith pulmonary tuberculosis than those in controls(p<0.02). 3) Patient's serum enhanced the generation of superoxide by blood monocyte obtained from patients with pulmonary tuberculosis and controls, but not in the case of PMA stimulated blood monocyte. Conclusion: The present study suggest that the phenomenon of M.tuberculosis escape the microbicidal action of macrophage was not result of suppressed superoxide generation by blood monocyte and pulmonary alveolar macrophage, rather there might be a factor to stimulate the generation of superoxide by blood monocyte in pulmonary tuberculosis patient serum, but the comparision with effect of control's serum on superoxide generation needs further elucidation.

• Journal of Yeungnam Medical Science
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• v.15 no.1
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• pp.55-66
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• 1998

Pathophysiological mechanism of hemorrhagic fever with renal syndrome (HFRS) is not fully understood. Major clinical findings of HFRS patients are widespread hemorrhage, acute renal failure and shock. Basic lesion is vascular injury with microvascular hemorrhage and relatively little inflammation. According to autopsy findings, renal medulla shows focal hemorrhage, tubular necrosis and interstitial mononuclear infiltrates. The predominant cell type in the renal and pulmonary interstitium is a fibroblast and it participates in the healing process at the injury site by secreting a large amount of extracellular matrix proteins. Cultured human lung fibroblasts and Mongolian gerbil fibroblasts were known to be good host cells for the hantaan virus. It is possible that not only the endothelial cell but also the fibroblast is a target of Hantaan virus and the fibroblast might be involved in the pathogenesis and the healing process in HFRS. Integrins are adhesion molecules, and act as receptors for many extracellular matrix proteins. Recently, there are many reports that cell surface integrins influence on some viral infections or reversely viruses influence on the expression of integrins. The ${\alpha}_5{\beta}_1$ integrin is a major receptor for the fibronectin which is an important extracellular matrix protein secreted by fibroblasts. In this study, the role of ${\alpha}_5{\beta}_1$ integrin in the infection of Hantaan virus was examined by using anti-${\alpha}_5{\beta}_1$, integrin, anti-${\alpha}_5$ integrin and anti-${\beta}_1$, integrin antibodies in chicken embryo fibroblasts (CEF) and Mongolian gerbil fibroblasts(MGF). The treatment of anti-${\alpha}_5{\beta}_1$, integrin antibody in CEF reduced the virion titers 26.8% and the amount of nucleocapsid N protein 32.6% when compared with control CEF. When MGF were treated with anti-${\alpha}_5$, anti-${\beta}_1$ and anti-${\alpha}_5{\beta}_1$ integrin antibodies, virion titers were reduced by 26.5%, 29.4% and 28.7% and the amount of nucleocapsid N protein were reduced by 65.2%, 59.7% and 72.6%. These results suggested that ${\alpha}_5{\beta}_1$ integrin might act as a receptor for the Hantaan virus or blocking of ${\alpha}_5{\beta}_1$ integrin influences on the viral replication in CEF and MGF. It is also possible that the blocking of only one subunit of integrin represents similar results in that of whole molecule.

• Radiation Oncology Journal
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• v.14 no.4
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• pp.281-290
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• 1996

Purpose : Chest irradiation leads to a significant cardiac injury in a number of patients. To prevent, or to reduce the risk of radiation-induced cardiac injury, pentoxifylline(PTX), a haemorrheologic agent that improves the blood flow through small blood capillaries has been employed. Materials and Methods : One hundred and eighty ICR mice were divided into three study groups: control, radiation alone, and radiation-pentoxifylline. Each group was subdivided into 12 subgroups: 1 3, 6 and 10 days and 2, 3, 4, 6, 8, 12, 16 and 20 weeks by observation Period after irradiation. The total 15Gy of radiation was delivered in a single fraction through anterior mediastinal port. Pentoxifylline was injected subcutaneously daily 50mg/kg to the back of the mice from the first day of irradiation throughout the observation period. The mice of each group after a certain observation period were sacrificed and sectioned for histopathologic examination of the heart. Result : The findings of acute radiation-induced carditis i.e., heterophilic infiltration and vacuolization and ballooning of endothelial cells were observed upto 6 weeks and reduced sharply afterwards. The late radiation effects including pericarditis with mononuclear cell infiltration, pericardial fibrosis, endothelial cell changes, myocardial degeneration and fibrosis present from 4 weeks onwards after irradiation but with various degree of severity. The overall process of pathologic changes of radiation-pentoxifylline group was similar to those of radiation alone group but the duration of acute stage was relatively short and the severity of late cardiac toxicity was much lesser compared with those of radiation alone group. Conclusion : Pentoxifylline can effectively reduce the late radiation-induced cardiac injury and reslve the acute effects relatively rapidly.

• Tuberculosis and Respiratory Diseases
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• v.52 no.2
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• pp.107-116
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• 2002

Background: Matrix metalloproteinases(MMP) are essential enzymes for tumor invasion and metastasis. Among the MMP family, elevated MMP-9 and stromelysin-3(STR-3) expression have been reported to be poor prognostic factors in lung cancer patients. To evaluate the possibility of a molecular diagnosis of lung cancer using peripheral blood, the mRNA expression level of MMP-9 and STR-3 was measured using a reverse transcriptase-polymerase chain reaction (RT-PCR) in patients with lung cancer. Methods : Ninety six patients(44 patients with lung cancer, 19 pulmonary infection, and 33 control) were included. To detect MMP-9 and STR-3 mRNA expression, RT-PCR was performed in peripheral blood mononuclear cells. ELISA was also used to measure the serum level of MMP-9. Results : MMP-9 was expressed more frequently in patients with a pulmonary infection(18/19, 94.7%) compared to lung cancer patients(26/44, 59.1%) or the controls (23/33, 69.7%) (p=0.018). On the other hand, STR-3 expression was observed more frequently in patients with lung cancer(37/44, 84.1%) compared to the lung infection patients(8/19, 42.1%) or control(20/33, 60.6%) (p=0.003). Among the lung cancer patients, MMP-9 was expressed more frequently when a tumor invaded the lymph nodes(17/24, 70.8%) compared to when a tumor did not(3/13, 23.1%) (p=0.005). The MMP-9 and STR-3 expression levels had no relationship with age, sex, tumor size, distant metastasis, or tumor histology. The serum MMP-9 concentration was not higher in lung cancer patients compared to patients with a pulmonary infection or the control subjects. Conclusion : STR-3 may be used as a diagnostic marker in the peripheral blood of lung cancer patients using RT-PCR. Further studies to evaluate the clinical significance of elevated STR-3 expression in lung cancer patients is recommended.