• Mycobiology
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• v.45 no.4
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• pp.297-311
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• 2017

Saprolegniasis is one of the most devastating oomycete diseases in freshwater fish which is caused by species in the genus Saprolegnia including Saprolegnia parasitica. In this study, we isolated the strain of S. parasitica from diseased rainbow trout in Korea. Morphological and molecular based identification confirmed that isolated oomycete belongs to the member of S. parasitica, supported by its typical features including cotton-like mycelium, zoospores and phylogenetic analysis with internal transcribed spacer region. Pathogenicity of isolated S. parasitica was developed in embryo, juvenile, and adult zebrafish as a disease model. Host-pathogen interaction in adult zebrafish was investigated at transcriptional level. Upon infection with S. parasitica, pathogen/antigen recognition and signaling (TLR2, TLR4b, TLR5b, NOD1, and major histocompatibility complex class I), pro/anti-inflammatory cytokines (interleukin $[IL]-1{\beta}$, tumor necrosis factor ${\alpha}$, IL-6, IL-8, interferon ${\gamma}$, IL-12, and IL-10), matrix metalloproteinase (MMP9 and MMP13), cell surface molecules ($CD8^+$ and $CD4^+$) and antioxidant enzymes (superoxide dismutase, catalase) related genes were differentially modulated at 3- and 12-hr post infection. As an anti-Saprolegnia agent, plant based lawsone was applied to investigate on the susceptibility of S. parasitica showing the minimum inhibitory concentration and percentage inhibition of radial growth as $200{\mu}g/mL$ and 31.8%, respectively. Moreover, natural lawsone changed the membrane permeability of S. parasitica mycelium and caused irreversible damage and disintegration to the cellular membranes of S. parasitica. Transcriptional responses of the genes of S. parasitica mycelium exposed to lawsone were altered, indicating that lawsone could be a potential anti-S. parasitica agent for controlling S. parasitica infection.

• Archives of Pharmacal Research
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• v.21 no.5
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• pp.537-542
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• 1998

to more effectively drive immune responses toward antigen-specific T helper type 2 (Th2) cell-mediated responses, we constructed a mammalian expression vetor (oPVA/IL4) carrying a fused gene in which the ovalbumin (OVA) cDNA was covalently linked to murine interleukin-4 (IL-4) cDNA. A biologically active OVA/IL4 DNA, as demonstrated by Wes tern blotting and cytokine bioassay. In tramuscular injection of BALB/c mice with the pOVA/IL4 DNA increased both the production of OVA-specific IL-4 by CD$4^{+}$ T cells and the ratio of anti-OVA lgG1 to anti-OVA lgG2a isotypes, while the injection with the pOVA DNA alone, or with the mixture of the pOVA and pIL4 DNA did no or little increase. furthermore, the OVA-specific, Th2 cell-mediated immune responses were significantly enhanced by multiple injections with the pOVA/IL4 DNA. These studies indicate that the direct linkage of an OVA gene to an IL-4 gene in the expression plasmid confines the effects of IL-4 to the OVA-specific cells, efficiently driving the immune response toward OVA-specific, Th2 cell-mediated responses.

• Proceedings of the KACD Conference
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• 2003.11a
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• pp.545-545
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• 2003

Chitosan is applied as a dressing for oral mucous wound and a tampon following radical treatment of maxillary sinus. Furthermore, it is being investigated as an absorbing membrane for endodontic and periodontic surgeries. A few studies have reported osteoconduction and osteogenesia at the site of chitosan implant in vivo. However, compared with soft tissue healing processes, the mechanisms concerning effects of chitosan for biological mineralization have not yet been resoil In the present study, we studied the gene expression pattern using cDNA microarray and RT-PCR analyses in hard tissue forming osteoblasts cultured with water-soluble and low molecular weight chitooligosaccharide. cDNA microarray analysis revealed that 16 genes were expressed at 〉1.5-fold higher signal ratio levels in the experimental group compared with the control group after 3 days. RT-PCR analysis showed that chitosan oligomer induced an increase in the expression of two genes, CD56 antigen and tissue-type plasminogen activator. Furthermore, the expression of mRNAs for BMP-2 was almost identical in the experimental and control groups after 3 days of culture, but slightly increased after 7 days of culture with chitosan oligomer. These results suggest that a super-low concentration of chitooligosaccharide could modulate the activity of osteoblastic cells through mRNA levels and that the genes concerning cell proliferation and differentiation can be controlled by water-soluble chitosan.

• Journal of Gastric Cancer
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• v.5 no.3 s.19
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• pp.206-212
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• 2005

Purpose: Angiogenesis has a critical role in tumor proliferation, invasion, and metastasis. In gastric cancer, tumor-associated macrophages and mast cells produce angiogenic factors such as VEGF, that inhibit the functional maturation of dendritic cells. The aim of this study is to identify tumor-associated macrophages, mast cells, dendritic cell infiltrations, and microvessel densities (MVD) to investigate the relationship between them and the prognosis for gastric-cancer patients. Materials and Methods: The subjects were 79 patients selected from those who had undergone a curative gastric resection for stomach cancer. With them, Immune-histochemical staining was done using CD34 for the MVD, CD68 antigen for macrophages, and S-100 protein for dendritic cells, and toluidine blue staining was done for mast cells. Results: Macrophage infiltration showed a statistically significant positive correlation with histologic differentiation and a negative correlation with invasion depth, nodal metastasis, and stage. S-100 (+) dendritic cells and mast cells had no significant correlations with histologic differentiation, invasion depth, nodal metastasis, distant metastasis, stage, and MVD. As survival, no statistically significant differences were seen between the variables. Conclusion: Tumor-associated macrophages should be evaluated as possible prognostic markers in gastric-cancer patients.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.1
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• pp.163-170
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• 2006

Nardostachyos Rhizoma (N. Rhizoma) belonging to the family Valerianaceae has been anti-arrhythmic effect, and sedation to the central nerve and a smooth muscle. We reported that the water extract of N. Rhizoma induced apoptotic cell death and differentiation in human promyelocytic leukemia (HL-60) cells. Cytotoxicity of N. Rhizoma was detected only in HL-60 cells (IC50 is about 200 ${\mu}g/ml$). The cytotoxic activity of N. Rhizoma in HL-60 cells was increased in a dose-dependent manner. We used several measures of apoptosis to determine whether these processes were involved in N. Rhizoma-induced apoptotic cell death. The high-dose (200 ${\mu}g/ml$) treatment of N. Rhizoma to HL-60 cells showed cell shrinkage, cell membrane blobbing, apoptotic bodies, and the fragmentation of DNA, suggesting that these cells underwent apoptosis. Treatment of HL-60 cells with N. Rhizoma time-dependently induced activation of caspase-3, caspase-8, and caspase-9 and proteolytic cleavage of poly(ADP-ribose) polymerase. Also, we investigated the effect of N. Rhizoma on cellular differentiation and proliferation in HL-60 cells. Differentiation and proliferation of HL-60 cells was determined through expression of CD11b and CD14 surface antigens using flow cytometry and nitroblue tetrazolium (NBT) assay, and through analysis of cell cycle using propidium iodide assay, respectively. N. Rhizoma induced the differentiation of HL-60 at the low-dose (100 ${\mu}g/ml$) treatment, as shown by increased expression of differentiation surface antigen CD11b, but not CDl4 and increased reducing activity of NBT. When HL-60 cells were treated with N. Rhizoma at concentration of $50{\mu}g/ml\;and\;100{\mu}g/ml$, NBT-reducing activities induced approximately 1.5-fold and 20.0-fold as compared with the control. In contrast, HL-60 cells treated with the N. Rhizoma-ATRA combination showed markedly elevated levels of 26.3-fold at $50{\mu}g/ml$ N. Rhizoma-0.1 ${\mu}M$ ATRA combination and 27.5-fold at 50 ${\mu}g/ml$ N. Rhizoma-0.2 ${\mu}M$ ATRA combination than when treated with N. Rhizoma alone or ATRA alone. It may be that N. Rhizoma plays important roles in synergy with ATRA during differentiation of HL-60 cells. DNA flow-cytometry indicated that N. Rhizoma markedly induced a G1 phase arrest of HL-60 cells. N. Rhizoma-treated HL-60 cells increased the cell population in G1 phase from 32.71% to 42.26%, whereas cell population in G2/M and S phases decreased from 23.61% to 10.33% and from 37.78% to 33.98%, respectively. We examined the change in the $p21^{WAF1/Cip1}\;and\;p27^{Kip1}$ proteins, which are the CKIs related with the G1 phase arrest. The expression of the CDK inhibitor $p27^{Kip1},\;but\;not\;p21^{WAF1/Cip1}$ were markedly increased by N. Rhizoma. Taken together, these results demonstrated that N. Rhizoma induces apoptotic cell death through activation of caspase-3, and potently inhibits the proliferation of HL-60 cells via the G1 phase cell cycle arrest in association with $p27^{Kip1}$ and granulocytic differentiation induction .

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.8
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• pp.4031-4036
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• 2012

Background: The negative signaling provided by interactions of the co-inhibitory molecule, programmed death-1 (PD-1), and its ligands, B7-H1 (PD-L1) and B7-DC (PD-L2), is a critical mechanism contributing to tumor evasion; blockade of this pathway has been proven to enhance cytotoxic activity and mediate antitumor therapy. Here we evaluated the anti-tumor efficacy of AAV-mediated delivery of the extracellular domain of murine PD-1 (sPD-1) to a tumor site. Material and Methods: An rAAV vector was constructed in which the expression of sPD-1, a known negative regulator of TCR signals, is driven by human cytomegalovirus immediate early promoter (CMV-P), using a triple plasmid transfection system. Tumor-bearing mice were then treated with the AAV/sPD1 construct and expression of sPD-1 in tumor tissues was determined by semi quantitative RT-PCR, and tumor weights and cytotoxic activity of splenocytes were measured. Results: Analysis of tumor homogenates revealed sPD-1 mRNA to be significantly overexpressed in rAAV/sPD-1 treated mice as compared with control levels. Its use for local gene therapy at the inoculation site of H22 hepatoma cells could inhibit tumor growth, also enhancing lysis of tumor cells by lymphocytes stimulated specifically with an antigen. In addition, PD-1 was also found expressed on the surfaces of activated CD8+ T cells. Conclusion: This study confirmed that expression of the soluble extracellular domain of PD-1 molecule could reduce tumor microenvironment inhibitory effects on T cells and enhance cytotoxicity. This suggests that it might be a potential target for development of therapies to augment T-cell responses in patients with malignancies.

• BMB Reports
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• v.28 no.6
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• pp.556-561
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• 1995

The purpose of this study was to establish an in vitro culture method of tumor-specific T cells, and determine the efficacy of the cultured tumor-specific cytotoxic T-lymphocytes (CTL) as an agent of anti-tumor immunotherapy against a murine lymphoma, TIMI.4. Tumor-specific T-lymphocytes derived from C57BL/6 mice (thy-1.2) immune to TIMI.4 were activated by in vitro stimulation with the irradiated TIMI.4 cells, and expanded by restimulation with TIMI.4 in the presence of the concanavalin A-stimulated rat spleen culture supernatant, and splenic antigen-presenting cells. In vitro restimulation enhanced markedly the proportion of $CD8^+$, a predominant surface marker of CTL and the cytotoxic activity in the cultured immune T cell population. The resulting TIMI.4-specific T cells were adoptively transferred into nude mice. The tumor cells residing in the host after 7 days of adoptive transfer to B6.PL (thy-1.1) mice were quantified by use of an antibody directed to the thy-1.2 allele. The TIMI.4 cells in the recipient nude mice were decreased in a dose-dependent manner. Anti-tumor activity of the TIMI.4-specific T cells was also demonstrated by a survival test, where the tumor-bearing nu/nu mice which received the activated T-cells survived about 30% longer than the control mice which received the tumor cells alone. These suggest that adoptive transfer of TIMI.4-specific T cells could be a candidate for effective therapy of the murine lymphoma.

• Korean Journal of Veterinary Pathology
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• v.2 no.2
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• pp.95-106
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• 1998

The prevalence of primary liver carcinoma (PLC) is relatively high in Clonorchis sinensis (CS) endemic areas in Korea. PLC is a malignant tumor which can be subclassified into hepatocellular carcinoma and cholangiocarcinoma(CC). CC has been associated with clonorchiasis, but it is unclear whether clonorchiasis is associated with hepatocarcinogenesis. This experiment was designed to investigate relationships between clonorchiasis and early changes of hepatocarcinogenesis. Sixteen Sprague-Dawley rats weighing 150g were divided into two groups of 8 rats in each. All rats were fed choline-devoid(CD) diet for 4 weeks. Group 1 was given 0.015-0.020% diethylnitrosamine(DEN) as drinking water for 1 week. After one week, the rats were treated orally with 1% N-acetylaminofluorene(AAF) (5 times per week for 2 weeks). Group 2 was treated equally to group 1 except for CS infection during AAF treatment. Two rats in each group were sacrificed at 4th, 5th, 6th and 7th week of the experiment. Livers were stained with OV -6, proliferating cell nuclear antigen(PCNA) and GST-p. Results were as follows: Group 2 livers showed more oval cell proliferation in parenchyma and portal areas at the 4th, 5th, 6th and 7th weeks than did livers of group 1 (p＜0.01). PCNA was mostly localized in oval cell populations, rather than hepatocytes and biliary cells. The ratio of oval cells to hepatocytes was much higher in group 2 than in group l(p＜0.01 The ratio of hepatocytes to biliary cells is higher in group 2 than in group 1 (p＜0.05), More group 2 acidophilic foci reacted to GST-p monoclonal antibody than in the noninfected group. It appeared that CS infection promoted potentially precancerous acidophilic foci and oval cell proliferation.

• Korean Journal of Head & Neck Oncology
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• v.13 no.2
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• pp.206-212
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• 1997

H$\"{u}$rthle cell neoplasm of the thyroid gland is an uncommon, but potentially malignant lesion. However, in many instances, the malignant potential of the H$\"{u}$rthle cell neoplasm is very difficult to judge histologically. For this reason, the biologic behavior of this tumor and its optimal treatment have come under considerable debate in recent years. In order to review the clinicopathologic features of the H$\"{u}$rthle cell neoplasm and to determine its optimal treatment modalities, we studied 26 patients with path logical proof of H$\"{u}$rthle cell tumor from January 1987 to September 1997. We also performed an immunohistochemical study using the monoclonal antibodies against antigen CD34 for the angiogenic activity of this tumor and evaluated the differences of microvessel density(MVD) between benign and malignant tumors. The age of the patients ranged from 1 to 71 years with a mean of 44.2 years. There were 6 males and 20 females(M : F= 1 : 3.3). The accuracies of fine needle aspiration biopsy and frozen section were very low; 6.3% and 34.8%, respectively. There were 20 benign tumors and 6 malignant tumors(23.1%). All the malignant tumors were microinvasive(intermediate) type which had minimal capsular invasion and most of them(5 cases) were diagnosed postoperatively. Any specific clinicopathologic differences were not seen between benign and intermediate groups. Most of the cases had conservative surgeries(15 ipsilateral lobectomy-isthmusectomy, 7 subtotal thyroidectomy) while total thyroidectomy was performed in 4 cases. Of the cases with malignant tumor, 2 had ipsilateral lobectomy-isthmusectomy, 3 had subtotal thyroidectomy and the remaining 1 had total thyroidectomy. Mean size of the tumors was 3.0 cm(0.1- 8.5 cm) in the greatest diameter and multiple tumors were seen in 6 cases(23.1 %). During the follow-up period, only one recurrence(3.8%) of benign tumor occurred but distant metastasis or cause-specific death was seen in the benign or intermediate groups. Mean MVDs of the benign(n=13) and intermediate(n=6) groups were $121.7{\pm}35.3$ and $114.3{\pm}31.7$, respectively and there was no statistical significance between them. In conclusion, because of the low accuracies of fine needle aspiration biopsy and frozen section for the H$\"{u}$rthle cell neoplasm, the extent of surgery could be individualized based on permanent pathologic examination; Conservative surgery would be adequate for patients with benign or intermediate H$\"{u}$rthle cell neoplasm and total or near-total thyroidectomy for those with definite malignancy.

• Tuberculosis and Respiratory Diseases
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• v.47 no.5
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• pp.691-696
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• 1999

Epithelioid hemangioendothelioma(EH) is a rare pulmonary vascular malignancy. Clinically, EH has been considered as an indolent, generally non-aggressive tumor. We report a case of EH which was confirmed by open lung biopsy. A 34-year-old woman was admitted for further evaluation of multiple small(less than 2cm in size) nodules, incidentally detected on screening chest radiograph. The chest CT showed multiple, relatively well-marginated, variable sized nodules at both whole lung. Transbronchial lung biopsy and transthoracic needle aspiration were nondiagnostic and open lung biopsy was performed from right middle lobe of lung. On light-microscopic examination, the nodules were composed of a poorly cellular hyaline core and a more cellular peripheral zone which extended into air space in a micropolypoid fashion and obliterated blood vessels. The tumor cells at the peripheral zone had intracytoplasmic vacuoles which suggested primitive, vascular differentiation. Immuno-histochemical study revealed the cellular area which gave positive reaction to factor VIII-related antigen. She received no specific therapy after open lung biopsy and chest X-ray films had showed no change for about two years.