• Journal of Microbiology and Biotechnology
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• v.15 no.3
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• pp.551-559
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• 2005

The recent rapid increase in genomic data related to many microorganisms and the development of computational tools to accurately analyze large amounts of data have enabled us to design several kinds of simulation approaches for the complex behaviors of cells. Among these approaches, dFBA (dynamic flux balance analysis), which utilizes FBA, differential equations, and regulatory events, has correctly predicted cellular behaviors under given environmental conditions. However, until now, dFBA has centered on substrate concentration, cell growth, and gene on/off, but a detailed hierarchical structure of a regulatory network has not been taken into account. The use of Boolean rules for regulatory events in dFBA has limited the representation of interactions between specific regulatory proteins and genes and the whole transcriptional regulation mechanism with environmental change. In this paper, we adopted the operon as the basic structure, constructed a hierarchical structure for a regulatory network with defined fundamental symbols, and introduced a weight between symbols in order to solve the above problems. Finally, the total control mechanism of regulatory elements (operons, genes, effectors, etc.) with time was simulated through the linkage of dFBA with regulatory network modeling. The lac operon, trp operon, and tna operon in the central metabolic network of E. coli were chosen as the basic models for control patterns. The suggested modeling method in this study can be adopted as a basic framework to describe other transcriptional regulations, and provide biologists and engineers with useful information on transcriptional regulation mechanisms under extracellular environmental change.

• Molecules and Cells
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• v.22 no.2
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• pp.168-174
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• 2006

Enhanced apoptosis has been observed in the placentas of women with preeclampsia, but few studies have examined changes at the molecular level. This study was designed to detect genes specifically expressed in full-term preeclamptic placentas. Tissue samples were collected immediately after cesarean delivery from 11 normal and 8 preeclamptic placentas at 35-40 weeks of gestation. Total RNAs were extracted and hybridized to a cDNA microarray. Results were confirmed by reverse-transcription polymerase chain reaction (RT-PCR), Western blotting and immunohistochemistry. Hematoxylin and eosin and TUNEL staining were also performed to confirm apoptosis in preeclamptic placentas. Among 205 genes, three were up- or downregulated in preeclamptic placentas. The expression of caspase-10 and death receptor 3 (DR-3) was significantly increased, whereas insulin-like growth factor binding protein-3 (IGFBP-3) was strongly downregulated. RT-PCR analysis and Western blotting confirmed these effects. Immunohistochemical analysis showed that the DR-3, caspase-10 and IGFBP-3 proteins were localized in the syncytial membrane. Apoptosis in the trophoblast was also increased in term placentas from women with pregnancies complicated by preeclampsia. These results suggest that caspase-10, DR-3 and IGFBP-3 are involved in apoptosis in the preeclamptic placenta.

• KSBB Journal
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• v.29 no.1
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• pp.36-41
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• 2014

Skin disease is one of the most common diseases and its incidence is increasing dramatically in modern society. Specially, many attempts have been made to treat chronic skin inflammation diseases, such as psoriasis and atopic dermatitis, but effective therapies for the immune cell-mediated skin diseases, including psoriasis and atopic dermatitis have not been developed. Until recently, several drug candidates which were claimed to be effective for skin diseases have been reported, but most of them are not used to treat chronic skin disease. Especially, Psoriasis is characterized by excessive growth and aberrant differentiation of keratinocytes, but is fully reversible with appropriate therapy. The trigger of the keratinocyte response is thought to be activation of the cellular immune system, with T cells and various immune-related cytokines. Formation of new blood vessels starts with early psoriatic changes and disappears with disease clearance. Several angiogenic mediators are up-regulated in psoriasis development. Contact- and mediator-dependent factors derived from keratinocytes, mast cells and immune cells may contribute to the strong blood vessel formation of psoriasis. New technologies and experimental models provide new insights into the role of angiogenesis in psoriasis pathogenesis. TMP and its derivatives themselves effectively inhibited in vitro cell migration, tube formation, and the expression of angiogenic factors. However, TMP and its derivatives induced side effects including hemolysis and local side effects. Therefore, in an attempt to reduce the toxicity and the undesirable side effects of TMP and derivatives, a liposomal formulation was prepared and tested for its effectiveness. TMP and derivatives liposomes retained the effectiveness of TMP in vitro while side effects were reduced. These results support the conclusion that TMP effectively inhibits in vitro angiogenesis, with the possibility that use as a psoriasis relief agent.

• Journal of Periodontal and Implant Science
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• v.24 no.1
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• pp.98-108
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• 1994

Gingival hyperplasia is frequently associated with the long-term use of phenytoin for control of convulsive disorder. The purpose of this study was to investigate on the effects of lipopolysaccharides (LPS), ursolic acid and oleanolic acid to phenytoin-induced cell activity in human gingival fibroblast. Human gingival fibroblasts were cultured form the healthy gingiva of orthodontic patients. Gingival fibroblasts were trypsinized and transferred to the weels of microtest plates. Fibroblast were cultured in growth medium added $5{\mu}g/ml$ of phenytoin, $5{\mu}g/ml$ of LPS, $10^{-7}M$ of ursolic acid and oleanolic acid. The passage number of cultured fibroblasts were fifth and eight. Cell morphology was examined by inverted microscope and the cell activity was measured by proliferation assay. Ursolic acid significantly modulated cell morphology into globular shape at the concentrantion of $10^{-7}M$ in the presence of phenytoin and LPS, and the cell activity was significantl decreased by ursolic acid or oleanolic acid regardless of the presence of phenytoin and LPS. These results suggested that the increased phenytoin-induced cell activity might be modulated by ursolic acid regardless of the presence of phenytoin and LPS. These results suggested that the increased phenytoin-induced cell activity might be modulated by ursolic acid or oleanolic acid. Further study is needed to clarify their toxicological effects on cellular modulation and mRNA expression change.

• Journal of Radiation Protection and Research
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• v.38 no.4
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• pp.166-171
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• 2013

While high-dose ionizing radiation results in long term cellular cytotoxicity, chronic low-dose (<0.2 Gy) of X- or ${\gamma}$-ray irradiation can be beneficial to living organisms by inducing radiation hormesis, stimulating immune function, and adaptive responses. During chronic low-dose-rate radiation (LDR) exposure, whole body of mice is exposed to radiation, however, it remains unclear if LDR causes changes in gene expression of the whole brain. Therefore, we aim to investigate expressed genes (EGs) and signaling pathways specifically regulated by LDR-irradiation ($^{137}Cs$, a cumulative dose of 1.7 Gy for total 100 days) in the whole brain. Using microarray analysis of whole brain RNA extracts harvested from ICR and AKR/J mice after LDR-irradiation, we discovered that two mice strains displayed distinct gene regulation patterns upon LDR-irradiation. In ICR mice, genes involved in ion transport, transition metal ion transport, and developmental cell growth were turned on while, in AKR/J mice, genes involved in sensory perception, cognition, olfactory transduction, G-protein coupled receptor pathways, inflammatory response, proteolysis, and base excision repair were found to be affected by LDR. We validated LDR-sensitive EGs by qPCR and confirmed specific upregulation of S100a7a, Olfr624, and Gm4868 genes in AKR/J mice whole brain. Therefore, our data provide the first report of genetic changes regulated by LDR in the mouse whole brain, which may affect several aspects of brain function.

• Korean Chemical Engineering Research
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• v.58 no.1
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• pp.122-126
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• 2020

In this study, we produced the micropatterned channel system using polydimethylsiloxane (PDMS) and micromolding in capillaries (MIMIC) technology and evaluated cellular polarity signals through high-resolved imaging at the single-cell level. In cells treated with platelet-derived growth factor (PDGF), three types of key signals in cell migration; phosphoinositide 3-kinase (PI3 K), Rac, and Actin, were strongly activated in the front area compared to the rear region, whereas myosin light chain (MLC) showed no notable activity in the front and rear areas. Our results will, therefore, provide important information and methodology for studying the correlation between cell polarity signals and cell migration under the newly defined microenvironment.

• Journal of Ginseng Research
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• v.40 no.4
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• pp.431-436
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• 2016

Background: Although numerous studies of the anticancer activities of Korean Red Ginseng (KRG) have been performed, the therapeutic effect of KRG on leukemia has not been fully elucidated. In this study, we investigated the antileukemia activities of KRG and its cellular and molecular mechanisms. Methods: An established leukemia tumor model induced by xenografted T cell lymphoma (RMA cells) was used to test the therapeutic activity of KRG water extract (KRG-WE). Direct cytotoxic activity of KRG-WE was confirmed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The immunomodulatory activities of KRG-WE were verified by immunohistochemistry, nitric oxide production assay. The inhibitory effect of KRG-WE on cell survival signaling was also examined. Results: Orally administered KRG-WE reduced the sizes of tumor masses. Levels of apoptosis regulatory enzymes and cleaved forms of caspases-3 and -8 were increased by this extract. In addition, expression of matrix metalloproteinase-9, a metastasis regulatory enzyme, was decreased by KRG-WE treatment. The proportion of CD11c+ cells was remarkably increased in the KRG-treated group compared to the control group. However, KRG-WE did not show significant direct cytotoxicity against RMA cells. Conclusion: Our results strongly suggest that the KRG might have antileukemia activity through CD11c+ cell-mediated antitumor immunity.

• 한국균학회소식:학술대회논문집
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• 2018.05a
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• pp.11-11
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• 2018

Cryphonectria parasitica, chestnut blight fungus, has a characteristic of decreasing pathogenicity when infected with Cryphonectria hypovirus 1. C. parasitica is known to be one of the most representative model systems used to observe the interaction between viruses, plants and fungi. The mitogen-activated protein kinase (MAPK) pathway, which is well conserved in various organisms ranging from yeast to humans, functions in relaying phosphorylation-dependent signals within MAPK cascades to diverse cellular functions involved in the regulation of pheromone, cell wall integrity, and osmotolerance in filamentous fungi. Several genes in the MAPK pathway were revealed to be regulated by hypovirus, or to be involved in pathogenicity in C. parasitica. Among these pathways, the CWI pathway has aroused interest because CpBck1, an ortholog of yeast Bck1 (a CWI MAPKKK), was previously reported to be involved in cell wall integrity and sectorization. Interestingly, sporadic sectorization was observed in the CpBck1 mutant and sectored phenotypes were stably inherited in the progeny that were successively transferred from sectored mycelia. In this study, we analyzed the biological function of CpSlt2, downstream gene of CpBck1, to confirm whether the sectorization phenomenon occurred in the specific single gene or cell wall integrity (CWI) pathway. As results, the CpSlt2-null mutant exhibited marked changes in colonial growth, near absence of conidiation and aerial hyphae, abnormal pigmentation, CWI-related phenotypic defects, and dramatically impaired virulence. As cultivation of the mutant strains progressed, the majority of the colonies showed sporadic sectorization and mycelia from the sectored area stably maintained the sectored phenotype. These results suggest that the unique sectorization is CWI pathway-specific, though the components in the same CWI pathway have common and specific functions.

• Macromolecular Research
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• v.16 no.8
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• pp.695-703
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• 2008

Nanoparticles have tremendous potential in cancer prevention, detection and augmenting existing treatments. They can target tumors, carry imaging capability to document the presence of tumors, sense pathophysiological defects in tumor cells, deliver therapeutic genes or drugs based on the tumor characteristics, respond to external triggers to release an appropriate agent, document the tumor response, and identify the residual tumor cells. Nanoparticles < 30 nanometers in diameter show unexpected and unique properties. Furthermore, particles < 5 nanometers in size can easily penetrate cells as well as living tissues and organs. This study evaluated the safety of nano materials in a living body and the relationship between the living tissue and synthetic nano materials by examining the in-vitro cytotoxicity of poly(lactic-co-glycolic) acid (PLGA) nano-spheres and fluorescein isothiocynate(FITC)-labeled dendrimers as polymer nanoparticles. PLGA was chosen because it has been used extensively for biodegradable nanoparticles on account of its outstanding bio-compatibility and its acceptance as an FDA approved material. The dendrimer was chosen because it can carry a molecule that recognizes cancer cells, a therapeutic agent that can kill those cells, and a molecule that recognizes the signals of cell death. Cytotoxicity in L929 mouse fibroblasts was monitored using MTT assay. Microscopic observations were also carried out to observe cell growth. All assays yielded meaningful results and the PLGA nanoparticles showed less cytotoxicity than the dendrimer. These nano-particles ranged in size from 10 to 100 nm according to microscopy and spectroscopic methods.

• Korean Journal of Veterinary Research
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• v.45 no.3
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• pp.375-379
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• 2005

Porcine juvenile pustular psoriasiform dermatitis (PJPPD) is a disease of young pigs and characterized by nonpruritic round eruption of skin. The cause of this disease is yet undetermined but is presumed to be genetic predisposition. There may be few opportunities for veterinarian to detect this disease compared with actual situation in field because these lesions resolve spontaneously in two months. The authors detected spontaneous PJPPD case and performed clinical and pathological studies on three pigs from one farm. The specific skin lesions were observed in the forty-day old pigs of mixed breed, which were produced by the sows received semen from the same boar, restrictively. However, there was no skin lesion of pigs in suckling or fattening periods. Grossly, lesions were commonly found on the ventral abdominal part as a papule and were spreaded to the skin of whole body. With the spreading of lesions centrifugally, skin was showed as a umbilicated plaques or mosaic pattern with a few pustules or crusts. Microscopically, the most prominent lesion was the psoriasiform hyperplasia with acanthosis, down growth of rete ridges, exocytosis of eosinophils and neutrophils, ballooning degeneration of superficial epidermis, and koilocytic degeneration of keratinocytes. Additionally, there were moderate dermal edema and severe mixed cellular infiltration, especially eosinophils. No infectious agent which can cause the skin lesion, was detected or cultured, and no lesion caused by infectious agents was also observed, pathologically. With pathological results of this study, it is supposed that pathogenesis or severity of PJPPD may be related to the infiltration of eosinophil or hypersensitivity.