1.Detection and characterization of excretory/secretory proteins from Toxoplasma gondii by monoclonal antibodies.
The Korean Journal of Parasitology 2001;39(1):49-56
Excretory/secretory proteins (ESP) from Toxoplasma gondii were analyzed to define the function in the penetration process into host cells. Whole ESP obtained at 37 degrees C were composed of 15 bands with molecular mass of 110, 97, 86, 80, 70, 60, 54, 42, 40, 36, 30, 28, 26, 22, and 19 kDa. Five ESP of 86, 80, 42, 36, and 28 kDa were reacted with monoclonal antibodies (mAb), named as Tg386 (microneme), Tg485 (surface membrane), Tg786 (rhoptry), Tg378, and Tg556 (both dense granules), respectively. The ESP was released by a temperature-dependent/-independent manner and all at once whenever ready to pour out except Tg786. Each ESP was not exhausted within the parasite but the amount was limited. Tg786 was released continuously with increment, whereas Tg378 and Tg556 were ceased to release after 3 and 4 hr. Dense granular Tg378 and Tg556 were released spontaneously and constitutively before the entry into host cells also. The entry of T. gondii was inhibited by all the mAbs differentially. And the parasite deprived of ESP was inhibited to enter exponentially up to 90.1%. It is suggested that ESP play an essential function to provide appropriate environment for the entry of the parasite into host cells.
Animals
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*Antibodies, Monoclonal
;
*Antibodies, Protozoan
;
Antigens, Protozoan/*analysis/physiology
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Mice
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Mice, Inbred BALB C
;
Support, Non-U.S. Gov't
;
Temperature
;
Toxoplasma/*chemistry/pathogenicity
2.Protease activity of 80 kDa protein secreted from the apicomplexan parasite Toxoplasma gondii.
The Korean Journal of Parasitology 2003;41(3):165-169
This study describes the characterization of 80 kDa protease showing gelationlytic property among three proteases in the excretory/secretory proteins (ESP) from Toxoplasma gondii. The protease activity was detected in the ESP but not in the somatic extract of RH tachyzoites. This protease was active only in the presence of calcium ion but not other divalent cationic ions such as Cu (2+), Zn (2+), Mg (2+), and Mn (2+), implying that Ca (2+) is critical factor for the activation of the protease. The 80 kDa protease was optimally active at pH 7.5. Its gelatinolytic activity was maximal at 37 degrees C, and significant level of enzyme activity of the protease remained after heat treatment at 56 degrees C for 30 min or 100 degrees C for 10 min. This thermostable enzyme was strongly inhibited by metal chelators, i.e., EDTA, EGTA, and 1, 10-phenanthroline. Thus, the 80 kDa protease in the ESP secreted by T. gondii was classified as a calcium dependent neutral metalloprotease.
Animals
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Calcium/metabolism
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Endopeptidases/*metabolism
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Hydrogen-Ion Concentration
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Molecular Weight
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Temperature
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Toxoplasma/*enzymology
3.Toxoplasmacidal effect of HL-60 cells differentiated by dimethylsulfoxide.
Won Young CHOI ; Ho Woo NAM ; Jae Eul YOO
The Korean Journal of Parasitology 1988;26(4):229-238
In vitro culture of Toxoplasma gondii in HL-60 cells cnd cell-mediated immunity against Toxoplasma in dimethylsulfoxide(DMSO)-induced HL-60 cells, i.e., differentiation into granulocytes, were pursued. HL-60 cells were treated with various concentrations of DMSO, and 1.3%(v/v) for 3 day incubation was chosen as the optimal condition for differentiation into granulocytes. The degree of differentiation was assayed in physiological and functional aspects in addition to morphological point. When treated with 1.3% DMSO for 3 days, HL-60 cells did not synthesize DNA materials beyond background level, and showed active chemotactic response to chemotactic peptide, formyl-methionyl-leucyl-phenylalanine(FMLP). Morphologically promyelocytes of high nuclear/cytoplasmic(N/C) ratio changed to granulocytes of relatively low N/C ratio. The relationships between HL-60 cells or DMSO-induced HL-60 cells and Toxoplasma were examined after stain with Giemsa and fluorescent dye (acridine orange). HS-60 cells did not show any sign of toxoplasmacidal activity but showed intracellular proliferation of Toxoplasma to form rosette for 72 hr co-culture. In contrast, DMSO-induced HL-60 cells phagocytosed Toxoplasma within 1 hr, and performed a process of intracellular digestion of Toxoplasma thereafter. With the above results, it is suggested that phagosome-lysosome fusion is one of the critical events for the parasitism by Toxoplasma or for susceptibility of host cells. The in vitro culture system of this study has offered a defined condition to study the protozoan parasite-host cell interactions.
parasitology-protozoa
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Toxoplasma gondii
;
HL-60 cells
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dimethylsulfoxide
;
in vitro culture
;
dimethylsulfoxide
4.Pathological Analysis of 15 Cases of Phyllodes Tumors of the Breast.
Sung Nam KIM ; Woo Ho KIM ; Sang Kook LEE
Korean Journal of Pathology 1993;27(1):19-26
Retrospective clinicopathologic analysis of 15 patients with the phyllodes tumors(PT) of the breast, diagnosed at SNUH over 6 years period, was done. By light microscopy, 8 cases were diagnosed as benign, and 7 cases were diagnosed as malignant. Mean ages o the patients were 37 and 34 years in malignant and benign, respectively. Most of those cases were presented with a palpable mass of the breast. None of the patients with malignant PT had distant metastasis, Local recurrences were experienced in 3 patients among the malignant PT, and one patient among the benign PT. One of 7 malignant PT was coexisted with simultaneous ipsilateral infiltrating duct carcinoma. The clinical course was not well correlated with pathologic features. The prognostic significances of several histopathologic parameters were assessed for possible correlation with local recurrence, metastasis and death; stromal cellularity, stromal cellular atypism, mitotic activity, tumor contour, necrosis, tumor size and heterologous stromal elements. Immunohistochemistry using antibody to vimentin, proliferating cell nuclear antigen(PCNA) and epidermal growth factor receptor(EGF-R) were analysed. In the 5 cases of benign PT, the stromal cells stained diffusely positive for vimentin and 3 cases of malignant tumors show similar staining for vimentin. The percentage of PCNA-positive cells were higher in the malignant PT than in the benign ones; they were 3.5% to 60% in malignancy, while they were less than 60% in all benign PT. The results of EGF-R staining were correlated with the histologic classification; only 2 cases out of 8 benign PT show diffusely positive staining of EGF-R in the cytoplasm, but 6 cases out of 7 malignant PT show positive findings.
Neoplasm Metastasis
5.Left-Sided Appendicitis: A Case Report.
Ho Suk DOH ; Eun Seuk HONG ; Chang Woo NAM
Journal of the Korean Society of Emergency Medicine 2000;11(3):385-389
Frequent anomalies causing a left-sided appendix are situs inversus and malrotation. The ectopic position of the appendix frequently causes a delay or error in diagnosis because of atypical symptoms. A physical examination is of limited value unless dextrocardia is present. A left-sided appendix is a rare anomaly, but when other diseases are ruled out, it must be considered especially at the emergency department.
Appendicitis*
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Appendix
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Dextrocardia
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Diagnosis
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Emergency Service, Hospital
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Physical Examination
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Situs Inversus
6.Laparoscopy-assisted Billroth I Gastrectomy Compared with Hand-assisted Laparoscopic Surgery for Early Gastric Cancer -A Prospective Study-.
Nam Joon YI ; Young Woo KIM ; Ho Seong HAN
Journal of the Korean Surgical Society 2002;62(1):57-63
PURPOSE: To compare standard laparoscopy-assisted Billroth I gastrectomies including standard lymph node dissection (LABIG) with hand-assisted laparoscopic surgery with the HandPort system (HALS) for the removal of early gastric cancers (EGC). METHODS: A prospective study was performed on 26 patients of EGC at Ewha Womans University Mok-Dong Hospital from July 1999 to August 2001. Seventeen patients (Group L) received LABIG using conventional laparoscopy-assisted methods and 9 patients received LABIG using HALS (Group H). We used staplers for the anastomosis, and a standard D2 lymph node dissection was done with ultrasonic shears or electrocautery. RESULTS: In group L, pathologic reports revealed 14 EGC (stage IA 14 cases), and 3 pm cancers (stage IB 1 case, II 2 cases). In group H, there were 9 early gastric cancers (stage IA 8 cases, IB 1 case). Significant differences (P<0.05) were present between group L and H in regards to the number of harvested lymph nodes (30.8 vs 18.9), estimated blood loss (462.1 vs 286.7 ml) and postoperative transfusion amounts (0.59 vs 0 unit). There were no differences in the mean operating time, distance from the lesion to the resection margin, postoperative leukocyte count, frequencies for pain control, wound size, time to diet, weight loss, serum protein, and postoperative hospital stay. Complications were present in 1 case in group L (enterocutaneous fistula) and 1 case in group H (gastric atony). There was one conversion to open surgery in group H. CONCLUSION: LABIG including standard lymph node dissections with both standard laparoscopic surgery and HALS were performed with equal outcome. The choice of surgical method depends on the characteristics of the lesion and the patient's physical factors.
Conversion to Open Surgery
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Diet, Reducing
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Electrocoagulation
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Female
;
Gastrectomy*
;
Gastroenterostomy*
;
Hand-Assisted Laparoscopy*
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Humans
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Laparoscopy
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Length of Stay
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Leukocyte Count
;
Lymph Node Excision
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Lymph Nodes
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Prospective Studies*
;
Stomach Neoplasms*
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Ultrasonics
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Wounds and Injuries
7.Comparison of mecA Gene Detection with Susceptibility Testing Methods in Coagulase Negative Staphylococcus According to the New NCCLS Guidelines(1999).
Myung Hyun NAM ; Hee Yeon WOO ; Jang Ho LEE ; Nam Yong LEE
Korean Journal of Clinical Microbiology 2000;3(1):57-61
BACKGROUND: Coagulase negative staphylococcus (CNS) spp. is a major pathogenic organism of nosocomial and community-acquired urianry tract infections, and causes infrctions in the immunocompromised host, and in particular, bloodstream infetions in patent with indwelling devices. High prevalance of methicillin resistance has been noticed in CNS which also have been recongnized as an important multidrug resistant pathogen. The optimal phenotypic method for detecting methicillin resistance still remains controversial, and new guidelines for detecting methicillin resistance of CNS was proposed by NCCLS in January 1999. We evaluated the relationship between mecA gene by PCR method and antimicrobial susceptibility tests according to the new NCCLS guidelines. METHODS: A total of 82 CNS isolates were examined for MICs and penicillin MICs by disk diffusion and agar dilution method according to NCCLS guidelines, and detections, and detection of mecA gene by PCR. RESULT: In disk diffusion method, 66 strains (80.5%) and 63 strains (76.8%) showed resistance to penicillin and oxacillin, respectively, and in agar dilution method, 71 strains(86.6%) and 53 strains (64.6%), respectively. In PCR method, mecA genes were detected in 49 strains(59.8%). Comparing with mecA gene detection by PCR method, the sensitivity of disk diffusion and agar dilution method was 95.8% and 89.8%, repectively. However, the sensitivity of disk diffusion and agar dilution method was 65.3% and 75.5%, respectively using previous NCCLS criteria. CONCLUSION: The new criteria of NCCLS detects the methicillin resistance induced by mecA gene more sensitively than previous one.
Agar
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Coagulase*
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Diffusion
;
Immunocompromised Host
;
Methicillin Resistance
;
Oxacillin
;
Penicillins
;
Polymerase Chain Reaction
;
Staphylococcus*
8.Seroprevalence of toxoplasmosis in Korean pregnant women.
Kyoung Ju SONG ; Jong Chul SHIN ; Ho Joon SHIN ; Ho Woo NAM
The Korean Journal of Parasitology 2005;43(2):69-71
This study was performed in order to evaluate the sero-epidemiological status of toxoplasmosis in pregnant Korean women. Among 5, 175 sera and 750 amniotic fluid samples obtained from pregnant women, 41 serum samples (0.79%) and 10 (1.33%) amniotic fluid samples tested positive for IgG antibodies by ELISA. Fifty one cases showing a score more than 0.25 on ELISA were tested for PCR reaction against the SAG1 gene. Only one case of the 51 ELISA positive cases exhibited a positive reaction on all tests. This case had a history of acute nephropyelitis during early pregnancy, but fortunately, had delivered a phenotypically healthy baby. In this study, the seroprevalence of toxoplasmosis in pregnant women was found to be comparatively low, consistent with previous reports from Korea. However our trials, performed with a variety of diagnostic tools, were considered to be useful for the precise diagnosis of congenital toxoplasmosis.
Adult
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Animals
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Antibodies, Protozoan/*blood
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Female
;
Humans
;
Korea/epidemiology
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Pregnancy
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Pregnancy Complications/diet therapy/*epidemiology
;
Seroepidemiologic Studies
;
Toxoplasma/*immunology
;
Toxoplasmosis/*epidemiology
9.A case of right cornual twin pregnancy following IVF-ET after bilateral salpingectomy due to tubal pregnancy.
Jaeng Woo NAM ; Sung Ho KIM ; Sang Hun CHA ; Jin Ho IM
Korean Journal of Obstetrics and Gynecology 1993;36(7):2355-2359
No abstract available.
Female
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Humans
;
Pregnancy
;
Pregnancy, Tubal*
;
Pregnancy, Twin*
;
Salpingectomy*
;
Twins*
10.A case of right cornual twin pregnancy following IVF-ET after bilateral salpingectomy due to tubal pregnancy.
Jaeng Woo NAM ; Sung Ho KIM ; Sang Hun CHA ; Jin Ho IM
Korean Journal of Obstetrics and Gynecology 1993;36(7):2355-2359
No abstract available.
Female
;
Humans
;
Pregnancy
;
Pregnancy, Tubal*
;
Pregnancy, Twin*
;
Salpingectomy*
;
Twins*