• Parasites, Hosts and Diseases
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• v.32 no.4
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• pp.259-266
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• 1994

The role of macrophages was observed In intranasally infected CSH/HeJ mice with trophozoites (3 ×105) of Acnnthomoeba culbertsoni which was a kind of free-living amoebae inducing meningoencephalitis in human and experimental animals. The mortality was 60% in the group of intraperitoneally injected mice with silica (0.5 mg/0.5 ml). It was much higher than that of 10% in the group of amoeba infected mice without silica administration. The phagocytic index of peritoneal macrophages co-cultured with Toxoplasma gondii was estimated daily. In contrast to the control and amoeba infected group which didn't show significant fluctuation of the phagocytic indices, the silica administrated group revealed under 3% until day 3, and gradual increase up to 24.7% in day 5 which was same level of amoeba infected group without silica administration. The level of interleukin- lb (IL- lb) measured by ELISA was the highest in the amoeba infected group without silica injection and the lowest in the amoeba infected group with silica administration. In the test of the amoebicidal activity of mice peritoneal macrcphages Dl uitro, silica administration revealed reducing effect on amoebicidal activity of macrophages. In conclusion, macrophages were proven to play a significant role in defense mechanism against the development of experimentally induced Acnnthamoebo menigoencephalitis.

• Journal of fish pathology
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• v.22 no.3
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• pp.253-262
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• 2009

We conducted bacteriological and histopathological analysis for olive flounder Paralichthys olivaceus after experimental infection with Streptococcus parauberis (FP2284) isolated from diseased olive flounder under different stress conditions. Experimental challenge was performed in healthy flounder (40.4 g in average body weight) by intraperitoneal (i.p.) injection with $2{\times}10^{8}$ CFU/fish under normal (no stress) or netting (for 2 min, twice/day) stress condition. The cumulative mortalities of no-stress and netting stress group were 70% and 95%, respectively. The most prevalent changes observed in experimentally infected flounder were darkness of skin and inflammation of the heart. Severe pericarditis, myocarditis and fibrosis were observed in the heart of the affected flounder. The results of viable counts showed the number of bacteria of the heart tissue was maintained over the $10^{4}$ CFU $g^{-1}$ heart for 3 weeks after inoculation. Histological lesions of the heart was more extensive and gradual decrease in bacterial numbers of heart tissue was delayed under stress condition.

• Journal of Oral Medicine and Pain
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• v.38 no.1
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• pp.87-95
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• 2013

Osteoarthritis (OA) of the temporomandibular joint (TMJ) is a severe form of temporomandibular disorders (TMDs), presenting gradual breakdown of articular cartilage and subchondral bone by the functional load sustained to exceed the physiologic tolerance of the joint. In such a joint loaded, offensive bioactive materials such as matrix degrading proteins, cytokines, and free radicals increase in concentration to shift the tissue response in the joint to degeneration from regeneration or remodeling. Recently, it has been issued that obesity can play an offensive role in pathogenesis of OA in a metabolic way. Adipokines released by adipose cells are present at higher concentration in the arthritic joint and joints of obese individuals. However, because of conflicting data reported, further scientific study should be performed to elucidate the practical role of adipokines in pathogenesis of TMJ OA. As far as the clinical signs and symptoms of TMJ OA are not much different from those of other forms of TMD and any definitive treatment modality to control directly the bone resorptive activity is not available yet, the treatment of TMJ OA should be directed to reduce the physical load and enhance the physiologic tolerance of the joint by means of conservative treatment such as physical therapy, medication, and occlusal splint therapy for sufficient period and, if needed after that, supplementary surgical procedure such as intra-articular injection, arthrocenthesis, and arthroscopic surgery that have turned out to be effective to control OA signs and symtpoms. Enthusiastic reassurance and motivation for patients to control behaviors for themselves to reduce unnecessary functional load in daily life is very important for the joint to reach to more favorable orthopedic stability of the TMJ more quickly, guaranteeing more successful management TMJ OA.

• Tuberculosis and Respiratory Diseases
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• v.38 no.2
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• pp.143-154
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• 1991

Pneumconiosis is a sort of pulmonary fibrosis consequent to the inhalation of the respirable dusts. Thus, the pathogenesis of silicosis have concentrated largely on the early response of alveolar macrophage and the later fibroblastic stimulation. But the role of the other cells and continuing cell injury in the pathogenesis has not been fully studied. And the chemical factors such as prostaglandin, fibroblast stimulating factor and inhibiting factor and chemotaxin are also participated in the mechanism of pulmonary fibrosis in silicosis. In order to clarify the role of alveolar cells and prostaglandin, we investigated the changes of the cellularities in bronchoalveolar lavage fluid and tissue pathology in the experimental silicosis with the time sequence. The experimental animals were divided into 3 groups; control group received only intratracheal injection of 0.5 ml saline, silica group received the intratracheal instillation of 40 mg silica with the same amount saline, and aspirin group received 450 mg/kg of aspirin after silica instillation. The results were as follows: 1) The total cells of bronchoalveolar lavage fluid in the silica group markedly increased in comparison with the control group, but there was no significant difference between the silica and aspirin groups. 2) The percentages of alveolar macrophages to the total number of cells in the silica group tended to be lower than those in the control group and also lower than those in the aspirin group at the 1st week after silica instillation. 3) The percentages of neutrophils to the total number of cells in the silica group were significantly higher than those in the control group during the entire period and also higher than those in the aspirin group at the 3rd day after silica instillation. 4) In the silica group, the percentages of lymphocytes to the total number of cells were increased 143 progressively with the time course and those were significantly higher than those in the control group from the 3rd week after silica administration. There were marked differences of lymphocyte percentages between the silica and aspirin groups at the 1st week after silica instillation. 5) The inflammatory change was observed in the rat lung at the 1st day after silica instillation. Also the silicotic nodule appeared in the silica group at the 1st week but we could not find out that nodule in the aspirin group at that time. The fibrotic changes in the rat lung tended to be increased progressively with the time course, therefore, the diffuse fibrotic pattern appeared in the whole field at the 20th week after silica instillation. 6) By the electron microscopy, there were gradual increases of phagosomes and vacuoles in the alveolar macrophage in the silica group as compared with the control group. These results suggest that the neutrophils and the lymphocytes have also participated in the pulmonary fibrosis even though the alveolar macrophage has a major role, and prostaglandin mediate the inflammation and pulmanary fibrosis in the experimental silicosis.

• The Korean Journal of Nuclear Medicine
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• v.30 no.3
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• pp.325-331
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• 1996

Purpose : To assess the functional change of salivary gland, recovery of salivary destruction, difference of susceptibility to irradiation between the parotid and sub-mandibular gland, correlation between the xerostomia and excretory rate by irradiation in salivary scan using $^{99m}Tc$-pertechnetate in patients with head and neck cancer. Materials and Methods : We evaluated 19 patients with head and neck cancer who had taken $^{99m}Tc$-pertechnetate salivary gland scan before, during and after radiotherapy. We measured the uptake of radioactivity every 5 minutes for 60 minutes after injection of $^{99m}Tc$-pertechnetate(370MBq). We also evaluated the first excretory function stimulated by 5% citric acid at 30 minutes after injection of $^{99m}Tc$-pertechnetate and then the second excretory function stimulated by 10% citric acid at 45 minutes. Results : The mean uptake curves showed a sharp increase at the 1st week of radiotherapy and then showed a gradual decrease afterwards during radiotherapy. And the mean uptake curves after radiotherapy Persistently decreased on follow up scans without being recovered. The excretory rates decreased gradually as radiation dose increased and were not recovered after radiotherapy. Our study was not satisfactory enough to show the difference of susceptibility to irradiation between the parotid and salivary gland and the correlation between the symptom of xerostomia and the change of the excretory rates. Conclusion : The parotid and submandibular gland scans using $^{99m}Tc$-pertechnetate are useful in the assessment of the functional change of the salivary gland by radiotherapy and predicted the functional change of the salivary gland until 1 year-follow up scan.

• Parasites, Hosts and Diseases
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• v.27 no.3
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• pp.177-186
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• 1989

Observations were made on the differences in cell-mediated immune responses in the mice infected with strongly pathogenic Naegleria fewleyi ITMAP 359, weakly pathogenic Naegzeria jadini 0400, or non.pathogenic Naegleria gruberi EGB, respectively. Variations in cell-mediated responses and changes in antibody titers according to the duration after infection wore noted. Infections were done by dropping $5{\;}{\mu}l$ saline suspension containing $10{\times}10^4$ trophozoites cultured Bxenically in the CGVS medium into the right nasal cavity of ICR mice aging about 6~7 weeks, under the anesthesia by intraperitoneal injection of'secobarbital. Following infection, delayed type hypersensitivity(DTH) iesponses in the footpad and blastogenic responses of the mouse spleen cells using [$^3H$]-thymidine were observed on the day 1, 4, 7, 10 and 14 after infection. For the preparation of amoeba Iysates, each of cultured trophosoites were homogenized with an ultrasonicator, and centrifugated at 20,000 g. The supernatants of amoeba Iysates were used as the mitogen'and antigen for ELISA. Confanavalin A(Con. A) and lipopolysaccharide(LPS) were also used as mitogens in the blastogenic response. 1. The mice infected with N, fowleri showed the mortality rate of 75.7%. The rate was 6.2% for the N. jadini infected group, while no dead mouse was observed for N. gruberi infections. 2. In regard to DTH responses in the H. fewleri infected mice, the level increased in com- parison to the control group but declined after 7 days. An increase was also noted for the JV. jadini group after 1 day, but gradual decreases were observed through the infection period. In addition, no difference was noted between the N. gruberi infected and control groups. 3. Concerning the blastogenic response of the splenocytes, it increased after 10 days in the experimental group of N, fcwleri infection, but the differences ware not statistically significant compared with control group. It was evident that N. jadini group was not different from control group either, while there was a tendency of decrease in SV. gruberi infected group. In regard to the blastogenic response of the splenocytes by LPS, it was found that the N. fowlgri, N. jadini and N. gruberi infected groups had no differences from the control group. 4. The serum antibody titer of N. fcwleri and N. jadini infected mice increased from the day 7 and 14 after infection respectively, while the N. gruberi infected mice showed no increase. In summary of the results, it was observed that there were differences in the cell-mediated immune responses and serum antibody titers in the mice infected with strongly pathogenic JV. fowleri, weakly pathogenic N. jadini, or non.pathogenic N. gruberi, respectively.

• Korean Journal of Remote Sensing
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• v.38 no.2
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• pp.139-151
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• 2022

SAGD (Steam-Assisted Gravity Drainage) method is widely used for oil recovery in oil sands regions. The SAGD operation causes surface displacement, which can affect the stability of oil recovery plants and trigger various geological disasters. Therefore, it isimportant to monitor the surface displacement due to SAGD in the oil sands region. In this study, the surface displacement due to SAGD operations of the Athabasca oil sands region in Alberta, Canada, was observed by applying Permanent Scatterer Interferometric Synthetic Aperture Radar (PSInSAR) technique to the Sentinel-1 time series SAR data acquired from 2016 to 2021. We also investigated the construction and expansion of SAGD facilitiesfrom Landsat-7/8 time seriesimages, from which the characteristics of the surface displacement according to the oil production activity of SAGD were analyzed. Uplift rates of 0.3-2.5 cm/yr in the direction of line of sight were observed over the SAGDs and their vicinity, whereas subsidence rates of -0.3--0.6 cm/yr were observed in areas more than several kilometers away from the SAGDs and not affected by oil recovery activities. Through the analysis of Landsat-7/8 images, we could confirm that the SAGDs operating after 2012 and showing high oil production activity caused uplift rates greater than 1.6 cm/yr due to the subsurface steam injection. Meanwhile, very small uplift rates of several mm per year occurred over SAGDs which have been operated for a longer period of time and show relatively low oil production activity. This was probably due to the compression of reservoir sandstone due to continuous oil recovery. The subsidence observed in areas except for the SAGDs and their vicinity estimated to be a gradual land subsidence caused by melting of the permafrost. Considering the subsidence, it was expected that the uplift due to SAGD operation would be greater than that observed by the PSInSAR. The results of this study confirm that the PSInSAR can be used as an effective means for evaluating productivity and stability of SAGD in the extreme cold regions.