• Tuberculosis and Respiratory Diseases
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• v.52 no.3
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• pp.251-259
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• 2002

Background : Reduced lung compliance and increased lung resistance are the primary lung mechanical abnormalities in acute respiratory distress syndrome (ARDS). Although there is little information regarding the mechanisms responsible for the increases in the respiratory resistance of ARDS, bronchodilators have been frequently administered in mechanically ventilated ARDS patients. To determine the effect of a bronchodilator on the respiratory mechanics depending on the level of applied positive end-expiratory pressure (PEEP), the changes in the respiratory mechanics by salbutamol inhalation was measured under the variable PEEP level in patients with ARDS. Materials and Methods : Fifteen mechanically ventilated paralyzed ARDS patients (14 of male, mean age 57 years) were enrolled in this study. The respiratory system compliance, and the maximum and minimum inspiratory resistance were obtained by the end-inspiratory occlusion method during constant flow inflation using the CP-100 pulmonary monitor (Bicore, Irvine, CA, USA). The measurements were performed at randomly applied 8, 10 and 12 cm $H_2O$ PEEP before and 30 mins after administrating salbutamol using a meter-dose-inhaler (100ug${\times}$6). Results : 1) The maximum inspiratory resistance of the lung was higher than the reported normal values due to an increase in the minimal inspiratory resistance & additional resistance. 2) The maximum inspiratory resistance and peak airway pressure were significantly higher at 12cm $H_2O$ of PEEP compared with those at 10cm $H_2O$ of PEEP. 3) Salbutamol induced a significant decrease in the maximum and the minimum inspiratory resistance but no significant change in the additional resistance only was observed at 12cm $H_2O$ of PEEP(from $15.66{\pm}1.99$ to $13.54{\pm}2.41$, from $10.24{\pm}2.98$ to $8.04{\pm}2.34$, and from $5.42{\pm}3.41$ to $5.50{\pm}3.58cm$ $H_2O$/L/sec, respectively). 4)The lung compliance did not change at the applied PEEP and salbutamol inhalation levels. Conclusion : The bronchodilator response would be different depending on the level of applied PEEP despite the increased respiratory resistance in patients with ARDS.

• Tuberculosis and Respiratory Diseases
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• v.67 no.1
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• pp.14-20
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• 2009

Background: The pathophysiologic mechanisms of radiation-induced lung injury should be elucidated to enhance the therapeutic efficacy of radiotherapy and to manage patients exposed to serious radiation by accident. It has been suggested that pro-inflammatory cytokines play an important role in radiation-induced effect on the lung. This study was aimed to investigate changes in pro-inflammatory cytokines such as TNF-$\alpha$, MIP-2, IL-1$\beta$ and HMGB1, a newly recognized inflammatory mediator. Methods: The chests of BALB/c mice were selectively irradiated with single fraction of 20 Gy and then sacrificed at indicated times. Pathologic changes in the lung were examined after H&E staining. The expression level of pro-inflammatory cytokines was evaluated by ELISA kits in lung homogenate and in serum. Results: Radiation induced inflammatory changes and mild fibrosis in lung. Biphasic increase of TNF-$\alpha$ and IL-1$\beta$ was found in lung homogenate at 4 hours and at 3 weeks after radiation. The elevation in the second phase tended to be more intense. However, there was no similar change in serum. MIP-2 level was slightly increased in lung homogenate at 4 hours, but not at 3 weeks. HMGB1 was increased at 3 weeks in serum while there was no significant change in lung homogenate. Conclusion: Radiation induced a biphasic increase in TNF-$\alpha$ and IL-1$\beta$. The effective control of second phase cytokine elevation should contribute to preventing severe lung fibrosis caused by radiation.

• Tuberculosis and Respiratory Diseases
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• v.67 no.2
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• pp.95-104
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• 2009

Background: The pathophysiologic mechanisms of early acute lung injury (ALI) differ according to the type of primary insult. It is important to differentiate between direct and indirect pathophysiologic pathways, and this may influence the approach to treatment strategies. NF-$\kappa$B decoy oligodeoxynucleotide (ODN) is a useful tool for the blockade of the expression of NF-$\kappa$B-dependent proinflammatory mediators and has been reported to be effective in indirect ALI. The purpose of this study was to investigate the effect of NF-$\kappa$B decoy ODN in the lipopolysaccharide (LPS)-induced direct ALI model. Methods: Five-week-old specific pathogen-free male BALB/c mice were used for the experiment. In the preliminary studies, tumor necrosis factor (TNF)-$\alpha$, interleukine (IL)-6 and NF-$\kappa$B activity peaked at 6 hours after LPS administration. Myeloperoxidase (MPO) activity and ALI score were highest at 36 and 48 hours, respectively. Therefore, it was decided to measure each parameter at the time of its highest level. The study mice were randomly divided into three experimental groups: (1) control group which was administered 50 ${\mu}L$ of saline and treated with intratracheal administration of 200 ${\mu}L$ DW containing only hemagglutinating virus of Japan (HVJ) vector (n=24); (2) LPS group in which LPS-induced ALI mice were treated with intratracheal administration of 200 ${\mu}L$ DW containing only HVJ vector (n=24); (3) LPS+ODN group in which LPS-induced ALI mice were treated with intratracheal administration of 200 ${\mu}L$ DW containing 160 ${\mu}g$ of NF-$\kappa$B decoy ODN and HVJ vector (n=24). Each group was subdivided into four experimental subgroups: (1) tissue subgroup for histopathological examination for ALI at 48 hours (n=6); (2) 6-hour bronchoalveolar lavage (BAL) subgroup for measurement of TNF-$\alpha$ and IL-6 in BAL fluid (BALF) (n=6); (3) 36-hour BAL subgroup for MPO activity assays in BALF (n=6); and (4) tissue homogenate subgroup for measurement of NF-$\kappa$B activity in lung tissue homogenates at 6 hours (n=6). Results: NF-$\kappa$B decoy ODN treatment significantly decreased NF-$\kappa$B activity in lung tissues. However, it failed to improve the parameters of LPS-induced direct ALI, including the concentrations of tumor necrosis factor-$\alpha$ and interleukin-6 in BALF, myeloperoxidase activity in BALF and histopathologic changes measured by the ALI score. Conclusion: NF-$\kappa$B decoy ODN, which has been proven to be effective in indirect models, had no effect in the direct ALI model.

• The korean journal of orthodontics
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• v.25 no.4
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• pp.433-445
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• 1995

Tooth movement, the phenomena and mechanisms of which are still controversial, can be considered as part of the result of the inflammatory processes. The purpose of this study was to examine the activity of macrophage and T-cell, playing important roles in the immune reaction, in the periodontal ligament of dog, in which experimental tooth movement was performed. Six one and half year-old dogs, a control and 5 experimentals, were studied. Light force (50-75g) was applied by placing open-coil spring between left mandibular premolars ; heavy force (250-300g), between right mandibular premolars. Experimental dogs were sacrificed at 12 hours, 1, 3, 7 and 14 days since force application, respectively. And the histologic and the immunohistochemical evaluation on the obtained tissue were performed, using $\alpha$-1-antichymotrypsin and CD3 antibodies. The results were as follows : 1. There were more inflammatory cell infiltrations in heavy force group than in light force group until 3 days. But from 7 dsays on, no difference was not observed between groups ; Such an infiltration was more evident at pressure side than at tension side. 2. Osteoclastic activity at pressure side began to be seen in 12 hours, increasing until 7 days. After then it decreased ; Such an activity was more evident in heavy force group than in light force group. 3. Tearing of periodontal ligament and vascular dilatation at tension side began to be seen in 12 hours, increasing until 3 days. After then it decreased ; Such an observation was more evident in heavy force group than in light force group, but there was no difference between groups in 14 days. 4. $\alpha$-1-antichymotrypsin expression in control group was positive, mainly in sulcular epithelium, but negative in periodontal membrane, pulp, bone cells. 5. $\alpha$-1-antichymotrypsin expression in experimental group was more positive in pressure side than in tension side ; The expression was a little more positive in cervical area of tooth until 3 days, but after 7days, it was more positive in apical area. 6. $\alpha$-1-antichymotrypsin expression in light force group began to be observed in 12 hours and reached to the greatest level in 7 days, after which it decreased ; In heavy force group, it was the greatest in 3 days, after which it decreased. 3 Expression in the periodontium was almost negative.

• Journal of agricultural medicine and community health
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• v.12 no.1
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• pp.36-53
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• 1987

It is utmostly important to establish the efficient fitable way of peoples' active participation in primary health care especially in the areas where the public or governmental service input for the basic health care is insufficient like as in rural areas of Korea. In light of above reason, this study focused mainly on the evaluation of roles and activities of village health workers (VHWs) who were selected from grass- root level of village people in order to derive further motivation for active participation. This is believed to be a sort of feedback mechanisms. Actually, the authors collected the activity reports of VHWs who had been devoting themselves in the primary health care services of Jeomdong Area, of Yeoju Gun one of Korea University Community Health Action Programmes and survey record on the VHWs activity from correspondent people. 1 hose data were analyzed through computer programmed package. The activities performed by VHWs were limited to the performance in 1985 for conveniance. The summarized results were as follows; 1) General characteristics of VHWs. Among a total of 28 VHWs in the area, about 39.3g of them have been replaced up to the date since the implementation in 1983, because of moving out, occupational employment and of others. The age of majority (75.0%) lied between the range of 30-50, and educational background of 67.9% belonged to category of primary school graduation, about 50% of them experienced to be or were also entiled "chief of women club" of corresponding villages. 2) Work-load of VHWs. Each VHW was assigned for tasks of health care for average 55 households of 248 persons. They shared approximately 6 days a month for the activity in average and it covered 17 cases of basic health care in a month. A half of the VHWs performed home visits irregularly without solidified schedule. 3) Work performance analysis. Informations collected through VHWs were compared with data from official vital registration at local administration center "Myon Office" in 1985. VHWs collected 100.8 of new born, 116.2 of death, 58.3 of move in and 74.8 of move out in comparison with 100.0 of official registration each. Pregnant women of 79.8% of mothers among the total pregnancy of 94 which were confirmed as normally delivered or aborted cases by all means afterwards had been detected by VHWs as being pregnant and all of them received some of antenatal cares by VHWs. All(100%) of delivered women were detected by VHWs through home visits and they were cared postnatally. Whereas, according to the records of birth registration, the places of delivery were clinic in 33.7%, and mother's home in 66.3%, VHWs reported them to be clinic in 48.9%, midwifery in 20.2%. It was cleared that most of misinformation was caused by uncautious filling of birth registration at notification. Among the total of 717 eligible women under age 44 years, family planning status of 92.6% was reported by VHWs confirming practice of control to be 70.8% of reported fertile women. 4) Attitude of VHW on the roles and functions. Although 92.0% of VHWs expressed VHWs to be worthwhile, only 52.0% of them had dignity and satisfaction in their activity and 44.0% of them had passive attitude of working saying they followed direction regardlessly. Concerning difficulties in performance as a VHW, 60.7% of them pointed out lacking of medical and health related knowledge by themselves. Still, 64.0% of them thought visiting unfamilier house to be awful and 40.0% complained forms of activity to be difficult and hard. It was also revealed that 56.6% confessed lack of interest on community health service itself. Most of VHWs needed more educational training especially on clinical fields such as cares of gynecological diseases, hypertension, diabetes, and other chronic diseaes of the aged. Regular on-the-job basic trainings were said to be needed twice a year.

• Journal of the Korean Geographical Society
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• v.40 no.2 s.107
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• pp.221-241
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• 2005

Land Use and Land Cover Changes (LUCC) occur over a wide range of space and time scales, and involve complex natural, socio-economic, and institutional processes. Therefore, modelling and predicting LUCC demands an understanding of how various measured properties behave when considered at different scales. Understanding spatial and temporal variability of driving forces and constraints on LUCC is central to understanding the scaling issues. This paper aims to 1) assess the heterogeneity of land cover change processes over the landscape in northern Ghana, where intensification of agricultural activities has been the dominant land cover change process during the past 15 years, 2) characterise dominant land cover change mechanisms for various spatial scales, and 3) identify the optimal spatial scale for LUCC modelling in a savanna landscape. A multivariate statistical method was first applied to identify land cover change intensity (LCCI), using four time-sequenced NDVI images derived from LANDSAT scenes. Three proxy land use change predictors: distance from roads, distance from surface water bodies, and a terrain characterisation index, were regressed against the LCCI using a multi-scale hierarchical adaptive model to identify scale dependency and spatial heterogeneity of LUCC processes. High spatial associations between the LCCI and land use change predictors were mostly limited to moving windows smaller than 10$\times$10km. With increasing window size, LUCC processes within the window tend to be too diverse to establish clear trends, because changes in one part of the window are compensated elsewhere. This results in a reduced correlation between LCCI and land use change predictors at a coarser spatial extent. The spatial coverage of 5-l0km is incidentally equivalent to a village or community area in the study region. In order to reduce spatial variability of land use change processes for regional or national level LUCC modelling, we suggest that the village level is the optimal spatial investigation unit in this savanna landscape.

• Journal of the Korean Geographical Society
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• v.42 no.4
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• pp.488-505
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• 2007

The purposes of this research are twofold; 1) to verify spatial differences of tectonic movement using the spatial distribution of earthquakes, and 2) to infer mechanisms that generate spatial accumulation patterns of earthquakes in the Korean Peninsula. The first part of this sequential paper (Park, 2007) argues that the Korean Peninsula consists of four geostructural regions in which tectonic deformation and consequent geomorphological development patterns are different from each other Since this conclusion has been made by terrain analyses alone, it is necessary to verify this suggestion using other independent geophysical data. Because earthquakes are results of movement and deformation of land masses moving in different directions, the distribution of earthquake epicenters may be used to identify the direction and rates of land mass movement. This paper first analysed the spatial distribution of earthquakes using spatial statistics, and then results were compared with the spatial arrangement of geostructural regions. The spatial distribution of earthquakes in the Korean Peninsula can be summarized as the followings; firstly, the intensity of earthquakes shows only weak spatial dependency, and shows large difference even at adjacent regions. Secondly, the epicenter distribution has a clear spatial accumulation pattern, even though the intensity of earthquake shows a random pattern. Thirdly, the high density area of earthquakes shows a clear 'L' shape, passing through Pyeongannam-do, centered at Pyeongyang, and Hwanghae-do, Seosan and Pohang. The correlation coefficient between the density of earthquakes and distance from geostructral region boundaries is much higher than those between the density of fault lines and distance from tectonic division boundaries. Since fault lines and tectonic divisions in the Korean Peninsula are the results of long-term geological development, there is an apparent scale discrepancy to find significant correlations with earthquakes. This result verifies the research hypothesis that the Korean Peninsula is divided into four geostructral regions in which each has its own moving direction and spatial deformation characteristics. The existence of geostructural regions is also supported by the movement parrerns of land masses estimated from the GPS measurements. This conclusion is expected to provide a new perspective to understand the geomorphological developments and the earthquake occurrences in the Korean Peninsula.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.5C
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• pp.664-672
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• 2004

Widespread popularity of wireless data communication devices, coupled with the availability of higher bandwidths, has led to an increased user demand for content-rich media such as images and videos. Since such content often tends to be private, sensitive, or paid for, there exists a requirement for securing such communication. However, solutions that rely only on traditional compute-intensive security mechanisms are unsuitable for resource-constrained wireless and embedded devices. In this paper, we propose a selective partial image encryption scheme for image data hiding , which enables highly efficient secure communication of image data to and from resource constrained wireless devices. The encryption scheme is invoked during the image compression process, with the encryption being performed between the quantizer and the entropy coder stages. Three data selection schemes are proposed： subband selection, data bit selection and random selection. We show that these schemes make secure communication of images feasible for constrained embed-ded devices. In addition we demonstrate how these schemes can be dynamically configured to trade-off the amount of ded devices. In addition we demonstrate how these schemes can be dynamically configured to trade-off the amount of data hiding achieved with the computation requirements imposed on the wireless devices. Experiments conducted on over 500 test images reveal that, by using our techniques, the fraction of data to be encrypted with our scheme varies between 0.0244％ and 0.39％ of the original image size. The peak signal to noise ratios (PSNR) of the encrypted image were observed to vary between about 9.5㏈ to 7.5㏈. In addition, visual test indicate that our schemes are capable of providing a high degree of data hiding with much lower computational costs.

• Tuberculosis and Respiratory Diseases
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• v.40 no.3
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• pp.223-235
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• 1993

Background: Superoxide anion which was produced by macrophage and neutrophil has a defensive role to kill invasive microorganisms and also an injurious role to produce self lung damage. Production of oxygen free radicals including superoxide is a main mechanism of acute lung injury caused by bacterial endotoxin. Endotoxin is known to activate alveolar macrophage to produce increased oxygen free radicals after the stimulation with various biological materials (priming effect). Calcium is a very important intracellular messenger in that cellular process of superoxide production. Method: This experiment was performed to elucidate the effects of endotoxin and calcium on superoxide production by phorbol myristate acetate-stimulated alveolar macrophage and the effect of verapamil on priming effect of endotoxin. Results: 1) Preincubation of macrophages with endotoxin (E. coli 055-B5) primed the cells to respond with increased superoxide production after the stimulation with PMA. Priming with endotoxin ($10^{-1}$ug/ml) produced a maximal enhancement of superoxide production (43%). 2) Verapamil could inhibit the superoxide production by PMA stimulated macrophage regardless of the presence of extracellular calcium. This means that the inhibitory effect of verapamil is caused by a mechanism independent of blocking calcium influx. 3) Verapamil could inhibit the priming effect of endotoxin on alveolar macrophage (from 30% increment to 13% increment) and could inhibit the superoxide production by PMA-stimulated macrophage preincubated with endotoxin. Conclusion: We concluded that verapamil could inhibit the superoxide production by PMA-stimulated rat alveolar macrophage and also inhibit the priming effect of endotoxin on alveolar macrophage. These inhibitory effects of verapamil could be one of the mechanisms of verapamil effects on endotoxin induced lung injury.

• Tuberculosis and Respiratory Diseases
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• v.42 no.2
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• pp.184-205
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• 1995

Background: Pulmonary toxicity by bleomycin has multiple mechanisms including direct tissue toxicity due to oxygen-derived free radicals and indirect toxicity through amplification of pulmonary inflammation. To evaluate the effect of chelators or free radical scavenger to lung damage induced by bleomycin, penicillamine as a copper chelator, deferoxamine as an iron chelator and vitamin E as a free radical scavenger were administered. Methods: Two hundred Wistar rats were divided into five groups: Control, bleomycin treated, bleomycin-penicillamine treated, bleomycin-deferoxamine treated, and bleomycin-vitamin E treated groups. Rats sacrificed on day 1, day 3, day 4, day 7, day 14, and day 28 after treatment. Bronchoalveolar lavage, light microscopic and immunohistologic studies for type I, III, IV collagens, fibronectin, laminin and NBD phallicidin were evaluated. Results: There was a significant increase in the total cell counts of bronchoalveolar lavage on day 1 from all treated animals and vitamin treated group showed an abrupt decrease in total cell counts with decrease of neutrophils on day 3. Bleomycin-vitamin E treated group had the least histologic changes such as pulmonary fibrosis. The alveolar basement membranes were positive for type IV collegen and laminin. Basement membranes of bleomycin, bleomycin-penicillamine, or bleomycin-deferoxamine treated groups were disrupted and fragmented on day 4 or 7. The bleomycin-vitamin E treated group had intact basement membranes until day 28. Conclusion: Bleomycin-induced pulmonary fibrosis was related to the severity of acute injury to oxygen radicals or activation of neutrophils and disruption of basement membrane. Vitamin E seemed to be the most effective antioxidant in the inhibition of bleomycin-induced pulmonary injury and fibrosis.