• Journal of Plant Biotechnology
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• v.3 no.2
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• pp.83-88
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• 2001

A cell culture system of poplar (Populus alba x P.glandulosa) was established to test four different methods for evaluation of cellular stresses. Two different kinds of stresses were given to the cultures by adding either Pb(NO$_3$)$_2$ or paraquat and the cellular responses were monitored during a week period. While fresh weight reduction was observable in two days after the treatment of Pb(NO$_3$)$_2$, such changes were apparent only in later stage in paraquat treated cultures. Cells in paraquat treated cultures in the first 3 days showed no alteration in fresh weight as compared to untreated cultures, but had their MTT reducing activities completely inhibited. Neither Evans blue staining nor ion conductivity of the medium was consistent with fresh weight changes of the cultures. Overall, cell clumps formed during suspension culture appeared to interfere with staining and washing reactions and thus cause the assays unreliable. Among the four methods examined, fresh weight changes and MTT reducing activity appeared to be the most reliable and consistent.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.6
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• pp.699-705
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• 1997

Although it is known that neuronal cell death during development occurs by apoptosis, the mechanisms underlying excitatory amino acid-induced neuronal cell death remain poorly understood. In this study we have examined the mechanism by which L-glutamate, an excitatory amino acid neurotransmitter, induces cell death in PC12 cell lines. To characterize cell death, we employed sandwich enzyme-linked immunosorbent assay(ELISA) method for cellular DNA fragmentation, DNA agarose gel electrophoresis and chromatin staining by acridine orange and ethidium bromide after treating the PC12 cells with L-glutamate. L-Glutamate caused dose-dependent cell death with a maximum at 24 hrs after the treatment. These cellular fragmentation was blocked by pretreatment of MK-801, a noncompetitive N-methyl-D-aspartic acid(NMDA) receptor antagonist, and nerve growth factor(NGF). Analysis of DNA integrity from L-glutamate-treated cells revealed cleavage of DNA into regular sized fragments, a biochemical hallmark of apoptosis. The PC12 cells that were induced to die by L-glutamate treatment exhibited classical chromatin condensation under the light microscopy after acridine orange and ethidium bromide staining. These results suggest that apoptosis is one of the key features that are involved in L-glutamate-induced excitotoxic cell death in PC12 cells, and these cell death are mediated by NMDA receptor and depend on NGF.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.34 no.5
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• pp.518-524
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• 2008

Chromosome 18q alteration plays a key role in colorectal tumorigenesis, and loss of heterozygosity at 18q is associated with a poor prognosis in colon cancer. DCC(Deleted in Colorectal Cancer) is a putative tumor- suppressor gene at 18q21 that encodes a transmembrane protein with structural similarity to neural cell adhesion molecule that is involved in both epithelial and neuronal cell differentiation. DCC is implicated in regulation of cell growth, survival and proliferation. Thus, tumor progression in squamous cell carcinoma, stomach cancer, colorectal cancer correlates with downregulation of DCC expression. The mechanism for DCC suppression is associated with hypermethylation of the DCC gene promoter region. Hence, the goal of this study is to identify the promoter methylation responsible for the down-regulation of DCC expression in oral squamous cell carcinoma. 12 of tissue specimens for the study are excised and gathered from 12 patients who are diagnosed as SCC in department of OMS, dental hospital, dankook university. To find expression of DCC in each tissue samples, immunohistochemical staining, RT-PCR gene analysis and methylation specific PCR are processed. The results are as follows. 1. In the DCC gene RT-PCR analysis, 5(41.6%) of 12 specimens of oral squamous cell carcinoma did not expressed DCC gene. 2. In the promoter methylation specific PCR analysis, 5(41.6%) of 12 specimens showed promoter methylation of DCC gene. 3. In the immunohistochemical staining of poor differentiated and invasive oral squamous cell carcinoma, loss of DCC expression was observed. These findings suggest that methylation of the DCC gene may play a role in loss of gene expression in invasive oral squamous cell carcinoma.

• Journal of Microbiology and Biotechnology
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• v.32 no.4
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• pp.531-540
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• 2022

Due to the high incidence of malignant melanoma, the establishment of in vitro models that recapitulate the tumor microenvironment is of great biological and clinical importance for tumor treatment and drug research. In this study, 3D printing technology was used to prepare GelMA/PEGDA composite scaffolds that mimic the microenvironment of human malignant melanoma cell (A375) growth and construct in vitro melanoma micro-models. The GelMA/PEGDA hybrid scaffold was tested by the mechanical property, cell live/dead assay, cell proliferation assay, cytoskeleton staining and drug loading assay. The growth of tumor cells in two- and three-dimensional culture systems and the anti-cancer effect of luteolin were evaluated using the live/dead staining method and the Cell Counting Kit-8 (CCK-8) method. The results showed a high aggregation of tumor cells on the 3D scaffold, which was suitable for long-term culture. Cytoskeleton staining and immunofluorescent protein staining were used to evaluate the degree of differentiation of tumor cells under 2D and 3D culture systems. The results indicated that 3D bioprinted scaffolds were more suitable for tumor cell expansion and differentiation, and the tumor cells were more aggressive. In addition, luteolin was time- and dose-dependent on tumor cells, and tumor cells in the 3D culture system were more resistant to the drug.

• Journal of Periodontal and Implant Science
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• v.23 no.1
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• pp.56-66
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• 1993

The Langerhans cells are dendritic nonkeratinocytes found suprabasally in most stratified squamous epithelia, such as human epidermis and the epithelium of the oral mucosa including that of gingiva. After Paul Langerhans found it in the skin in 1968, there have been sturdies of it's function and distribution . Stingle et al. reported that the Langerhans cells seem able to present antigens and to stimulate T-lymphocytes. Shelley et al. discovered that they can take up contact allergens. Accordingly it has been suggested that Langerhans cells are important elements of p Peripheral cell mediated immune system. In this study, the gingival tissue of a adult periodontitis patient was taken and freeze dried. In one specimen, we used the CD1 monoclonal antbody to staining the Langerhans cell. The other specimen, we embedded in paraffin and staining it with S-100 monoclonal antibody. The purpose of this study was to use these specimens to find out the distribution, orientation, morphology of the Langerhans cell and to discover the increase or decrease of Langerhans cell in an increased inflammatory state. The results were obtained as follows : 1. Langerhans cells were distributed between the basal cell layer and spinous cell layer against the CD1 & S-100 monoclonal antibody. 2. Langerhans cessl were plentiful in the oral eptihelium, and there was very little in the sulcular epithelium. 3. There were no Langerhans cell in the junction epithelium and pocket lining epithelium. 4. The number of Langerhans cells that responsed to the CD1 & S-100 monoclonal antibody had a statistically difference. 5. As the infiltration of the lymphocyte into the connective tissue were increased, the number of Langerhans cells in the epithelium were increased. 6. As the inflammation was increased, Langerhans cells in the spinous cell layer were more increased than those of the basal layer.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.36 no.1
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• pp.1-6
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• 2010

Purpose: Chemokines are structurally related, small polypeptide signaling molecules that bind to and activate a family of transmembrane G protein-coupled receptors, the chemokine receptors. Recently, interaction between the chemokine receptor CXCR4 and its ligand, stromal cell-derived factor 1 (SDF-1 or CXCL12), has been found to play an important role in tumorigenicity, proliferation, metastasis and angiogenesis in many cancers such as lung cancer, breast cancer, melanoma, glioblastoma, pancreatic cancer and cholangiocarcinoma. Hence, the goal of this study is to identify the correlation of clinicopathological factors and the up-regulation of SDF-1 expression in oral squamous cell carcinoma. Material and methods: We studied the immunohistochemical staining of SDF-1, quantitative RT-PCR (qRT-PCR) of SDF-1 gene in 20 specimens of 20 patients with oral squamous cell carcinoma. Results: 1. In the immunohistochemical study of poor differentiated and invasive oral squamous cell carcinoma, the high level staining of SDF-1 was observed. And the correlation between immunohistochemical SDF-1 expression and tumor nodes metastases (TNM) classification of specimens was significant.($x^2$ test, P < 0.05) 2. In the SDF-1 gene qRT-PCR analysis, SDF-1 expression was more in tumor tissue than in carcinoma in situ tissue. Paired-samples analysis determined the difference of SDF-1 mRNA expression level between the cancer tissue and the carcinoma in situ tissue.(Student's t-test, P < 0.05) Conclusion: These findings suggest that up-regulation of the SDF-1 may play a role in progression and invasion of oral squamous cell carcinoma.

• The Journal of Korean Medicine
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• v.39 no.1
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• pp.35-43
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• 2018

Objectives: In the brain, glutamate is the most important excitable neurotransmitter in physiological and pathological conditions. However, the high level of glutamate induces neuronal cell death due to exitotoxicity and oxidative stress. The present study investigated to evaluate a possible neuroprotective effect of furosin isolated from Euphorbia helioscopia against glutamate-induced HT22 cell death. Methods: Furosin was isolated from methanol extract of Euphorbia helioscopia and examined whether it protects glutamate-induced neuronal cell death. The cell viability was determined using Ez-Cytox assay. Anti-oxidative effect of furosin was determined by DPPH scavenging activities, and the levels of intracellular reactive oxygen species (ROS) were determined by the fluorescent intensity after staining the cells with $H_2DCFDA$. To evaluate apoptotic cell death, we performed nuclear staining and image-based cytometeric analysis. Results: The cell viability was significantly increased by treatement with furosin compared with the treatment with glutamate. Furosin showed a strong DPPH radical scavenging activity ($EC50=1.83{\mu}M$) and prevented the accumulation of intra cellular ROS. Finally, the presence of 50 and $100{\mu}M$ furosin significantly the percentage of apoptotic cells compared with glutamate treatment. Conclusion: The present study found that furosin is a potent neuroprotectant against glutamate-induced oxidative stress through inhibition of apoptotic cell death induced by glutamate. Therefore, the present study suggests that furosin as a bioactive compound of E. helioscopia can be a useful source to develop a drug for the treatment of neurodegenerative diseases and acute brain injuries.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6513-6519
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• 2015

Background: Recent attention on chemotherapeutic intervention against cancer has been focused on discovering and developing phytochemicals as anticancer agents with improved efficacy, low drug resistance and toxicity, low cost and limited adverse side effects. In this study, we investigated the effects of Curcuma C20-dialdehyde on growth, apoptosis and cell cycle arrest in colon and cervical cancer cell lines. Materials and Methods: Antiproliferative, apoptosis induction, and cell cycle arrest activities of Curcuma C20-dialdehyde were determined by WST cell proliferation assay, flow cytometric Alexa fluor 488-annexin V/propidium iodide (PI) staining and PI staining, respectively. Results: Curcuma C20 dialdehyde suppressed the proliferation of HCT116, HT29 and HeLa cells, with IC50 values of $65.4{\pm}1.74{\mu}g/ml$, $58.4{\pm}5.20{\mu}g/ml$ and $72.0{\pm}0.03{\mu}g/ml$, respectively, with 72 h exposure. Flow cytometric analysis revealed that percentages of early apoptotic cells increased in a dose-dependent manner upon exposure to Curcuma C20-dialdehyde. Furthermore, exposure to lower concentrations of this compound significantly induced cell cycle arrest at G1 phase for both HCT116 and HT29 cells, while higher concentrations increased sub-G1 populations. However, the concentrations used in this study could not induce cell cycle arrest but rather induced apoptotic cell death in HeLa cells. Conclusions: Our findings suggest that the phytochemical Curcuma C20-dialdehyde may be a potential antineoplastic agent for colon and cervical cancer chemotherapy and/or chemoprevention. Further studies are needed to characterize the drug target or mode of action of the Curcuma C20-dialdehyde as an anticancer agent.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.280-280
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• 2010

Alzheimer disease is a progressive neurodegenerative disease of the aged, characterized by memory loss and dementia. For diagnosis of Alzheimer disease we have simply modified macrophage with amyloid beta bonded with different molecules. Modified Macrophage was observed with microscope for co-localization of amyloid beta molecule. For this experiment we used fluoroscene labeling substances. The macrophage was modified also with cell staining method. For cell staining method was used avidin-biotin reaction principles. All experiments were carried out on poly-L-lysine coated and sterilized glass substrates. In the presentation we will show the further investigations and applications with modified macrophage.

• The Korean Journal of Cytopathology
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• v.4 no.2
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• pp.133-139
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• 1993

A case of presacral chordoma in a 55-year-old male diagnosed by aspiration biopsy cytology Is reported. Cytologically, three cell types were recognized in a mucoid background. large, mononucleated or binucleated physaliphorous cells with vacuolated bubbly cytoplasm; small, uniform and rounded non-vacuolated cells; and cells with microvacuolated and plump cytoplasm. The diagnosis of chordoma was possible because typical radiological and cytomorphological features were supported by the results of special staining and immunohistochemical staining with the cell block specimen obtained from the fine needle aspiration.