• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.4
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• pp.339-347
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• 2000

An algicidal bacterium, Micrococcus sp. LG-5 against the harmful dinoflagellate, Cochlodinium polykrikoides was isolated. The optimal conditions for the highest algicidal activity of bacterial culture filtrate showed in the range of $20{\~}30^{\circ}C$, at pH 7.0 and $3.0{\%}$ of NaCl concentration. In addition, $IC_(50)(mean of 50{\%} inhibitory concentration)$ of the culture filtrate against C. polykrikoides after incubation of 5 days was $0.482{\%}$. To investigate heat and pH stability of the culture filtrate of Micrococcus sp. LG-5, the culture filtrate ($pore size, 0.1 {\mu}m$) was heated to $121^{\circ}C for 15 min$ and adjusted pH from 2.0 to 10.0. There were no significant changes in algicidal activity by heat treatment and the pH change between pH from 5.0 to 10.0. The algicidal substances produced from Micrococcus sp. LG-5 were mainly detected in the fraction of $10,000{\~}1,000$ MWCO (molecular weight cut-off). The culture filtrate of Micrococous sp. LG-5 showed antimicrobial activity against Enterococcus faecalis, Escheiichia coli, Uebsiella pneunioniae and Vibrio altinolyticus, but did not show against Pseudomonas aeminosa, P. Buorescens, Salmonella typhi, Staphylococcus aureus, V. cholerae and V parahaemolyicus. The culture filtrate of Micrococcus sp. LG-5 was examined against 16 phytoplankton species and showed the algicidal activity against Ajexandzium tuarense, Eutreptiella Drnnastin, Gymnodinium catenatum, G. mikimotoi, G. sanguineum, eyodinium impuaicum, Heterocapsa triquetra, Heterosipa akashiwo, Prorocentrum micans and Pyraminonas sp.. However no algicidal effects of Micrococcus sp. LG-5 were observed against Chlamydomonas sp., Cylindrotheoa closterium, P. mininum, P. triestimum, Pseudonieschia sp. and Sczipuiella trochoidea. On the other hand, algicidal activity on the tested marinelivefood was not detected except for Isochrysis galbana. In addition, physiological responses of cultured olive flounder (Paralichthys oliraceus) exposed to $1 and 10{\%}$ of the culture filtrate of Micrococcus sp. LG-5 were measured. There were no clear changes in AST, GGT, creatinine, urea, total cholesterol, total protein, albumine, $Mg^(+2), Ca^(+2), Na^+, K^+, and Cl^-$. These results indicate that olive flounders were not affected when they were exposed to the culture filtrate of Micrococcus sp. LG-5.

• Tuberculosis and Respiratory Diseases
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• v.51 no.6
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• pp.559-569
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• 2001

Background : Pleural effusion is one of the most common clinical manifestations associated with a variety of pulmonary diseases such as malignancy, tuberculosis, and pneumonia. However, there are no useful laboratory tests to determine the specific cause of pleural effusion. Therefore, an attempt was made to analyze the various types of pleural effusion and search for useful laboratory tests for pleural effusion in order to differentiate between the diseases, especially between a malignant pleural effusion and a non-malignant pleural effusion. Methods : 93 patients with a pleural effusion, who visited the Severance hospital from January 1998 to August 1999, were enrolled in this study. Ultrasound-guided thoracentesis was done and a confirmational diagnosis was made by a gram stain, bacterial culture, Ziehl-Neelsen stain, a mycobacterial culture, a pleural biopsy and cytology. Results : The male to female ratio was 56 : 37 and the average age was $47.1{\pm}21.8$ years. There were 16 cases with a malignant effusion, 12 cases with a para-malignant effusion, 36 cases with tuberculosis, 22 cases with a para-pneumonic effusion, and 7 cases with transudate. The LDH2 fraction was significantly higher in the para-malignant effusion group compared to the para-pneumonic effusion group [$30.6{\pm}6.4%$ and $20.2{\pm}7.5%$, respectively (p<0.05)] and both the LDH1 and LDH2 fraction was significantly in the para-malignant effusion group compared to those with tuberculosis [$16.4{\pm}7.2%$ vs. $7.6{\pm}4.7%$, and $30.6{\pm}6.4%$ vs.$17.6{\pm}6.3%$, respectively (p<0.05)]. The pleural effusion/serum LDH4 fraction ratio was significantly lower in the malignant effusion group compared to those with tuberculosis [$1.5{\pm}0.8$ vs. $2.1{\pm}0.6$, respectively (p<0.05)]. The LDH4 fraction and the pleural effusion/serum LDH4 fraction ratio was significantly lower in the para-malignant effusion group compared to those with tuberculosis [$17.0{\pm}5.8%$ vs. $23.5{\pm}4.6%$ and $1.3{\pm}0.4$ vs. $2.1{\pm}0.6$, respectively (p<0.05)]. Conclusion : These results suggest that the LDH isoenzyme was the only useful biochemical test for a differential diagnosis of the various diseases. In particular, the most useful test was the pleural effusion/serum LDH4 fraction ratio to distinguish between a para-malignant effusion and a tuberculous effusion.

• Tuberculosis and Respiratory Diseases
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• v.45 no.2
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• pp.301-310
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• 1998

Background: Cell mediated immune response mediated by interaction between CD4+ T lymphocytes and macrophagies is thought to play an important role in tuberculous pleurisy. This interaction is dependent on the interplay of various cytokines. The immunologic response of tuberculous pleurisy is thought to depend on the balance between helper T cell(Th1) cytokine Interleukin-12, Interferon gamma and Th2 cytokine IL-4, IL-10. To understand immunologic mechanism in tuberculous pleurisy and evaluate diagnostic value of these cytokines, the concentrations of Th1 cytokine IL-12, IFN -$\gamma$ and Th2 cytokine IL-10 were measured in tuberculous pleurisy and malignant pleural effusion group. Material and Methods: The concentrations of IL-10, IL-12 and IFN-$\gamma$ were measured by ELISA method in pleural fluids and serums of 20 patients with tuberculous pleurisy and 20 patients with malignant pleural effusion ADA activities were measured by spetrophotomery in pleural fluids of both groups. Results: In tuberculous pleurisy, the mean concentrations of IL-10, IL-12 and IFN-$\gamma$ of pleural fluids showed $121.3{\pm}83.7$ pg/mL, $571.4{\pm}472.7$ pg/mL and $420.4{\pm}285.9$ pg/mL. These were significantly higher than that of serum, $21.2{\pm}60.9$ pg/mL, 194.5 pg/mL, $30.1{\pm}18.3$ pg/mL respectively(p< 0.01). In malignant pleural effusion, the mean concentrations of IL-10, IL-12 and IFN-$\gamma$ of pleural fluids showed $88.4{\pm}40.4$ pg/mL, $306.5{\pm}271.1$ pg/mL and $30.5{\pm}54.8$ pg/mL respectively. Compared with that of serum ($43.4{\pm}67.2$ pg/mL, $206.8{\pm}160.6$ pg/mL, $14.6{\pm}3.3$ pg/mL), only IL-10 was significantly higher (p<0.001), but IL-12, IFN-$\gamma$ were not significant. In tuberculous pleural effusion compared with malignant pleural effusion, the concentration of IL-12, IFN-$\gamma$, ADA were significantly higher (p=value 0.046, <0.001, <0.001), but IL-10 was not significant. For differential diagnosis of tuberculous pleurisy from malignant pleural effusion, using cut-off value of IL-12, IFN-$\gamma$, ADA as 300 pg/mL. 100 pg/mL, 45 U/L, the sensitivity/specificity were 60%/70%, 90%/87.5%, 85%/90% respectively. Conclusion: In tuberculous pleurisy, IL-10, IL-12 and IFN-$\gamma$ were selectively concentrated highly in pleural space than serum. Compared with malignant pleural effusion, IL-12 and IFN-$\gamma$ were significantly higher, but IL-10 were not in tuberculous pleural effusion. The results suggest that Th1 pathway contributes to immune resistant mechanism in tuberculous pleurisy. IFN-$\gamma$ and ADA revealed useful methods of differential diagnosis in tuberculous pleurisy from malignant pleural effusion.