• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.3
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• pp.365-371
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• 2020

In this study, in order to recycle the stems of opuntia cactus discarded after harvesting the fruit, the cactus stems were powdered and applied as a cement-based admixture. The powder of cactus stem was mixed into the mortar, and its effect on the fresh properties and strength of the mortar was studied. The results were compared with the properties of mortars produced by mixing with a retarder sugar and a viscosity agent methyl-cellulose, which are conventional saccharide-based admixtures. Based on the test results, the cactus stem powder did not clearly show the effect as a retarding agent, whereas the flow and the air content were similar to those of the mortar mixed with methyl-cellulose. This indicated that the cactus stem powder can be used as a viscosity agent. It was found that the strength of the mortar tended to increase when the mixing ratio of the cactus stem powder was lower than 0.3%.

• Journal of Periodontal and Implant Science
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• v.51 no.5
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• pp.329-341
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• 2021

Purpose: Periodontal treatment aims at complete regeneration of the periodontium, and developing strategies for periodontal regeneration requires a deep understanding of the tissues composing the periodontium. In the present study, the stemness characteristics and gene expression profiles of cementum-derived cells (CDCs) were investigated and compared with previously established human stem cells. Candidate marker proteins for CDCs were also explored. Methods: Periodontal ligament stem cells (PDLSCs), pulp stem cells (PULPSCs), and CDCs were isolated and cultured from extracted human mandibular third molars. Human bone marrow stem cells (BMSCs) were used as a positive control. To identify the stemness of CDCs, cell differentiation (osteogenic, adipogenic, and chondrogenic) and surface antigens were evaluated through flow cytometry. The expression of cementum protein 1 (CEMP1) and cementum attachment protein (CAP) was investigated to explore marker proteins for CDCs through reverse-transcription polymerase chain reaction. To compare the gene expression profiles of the 4 cell types, mRNA and miRNA microarray analysis of 10 samples of BMSCs (n=1), PDLSCs (n=3), PULPSCs (n=3), and CDCs (n=3) were performed. Results: The expression of mesenchymal stem cell markers with a concomitant absence of hematopoietic markers was observed in PDLSCs, PULPSCs, CDCs and BMSCs. All 4 cell populations also showed differentiation into osteogenic, adipogenic, and chondrogenic lineages. CEMP1 was strongly expressed in CDCs, while it was weakly detected in the other 3 cell populations. Meanwhile, CAP was not found in any of the 4 cell populations. The mRNA and miRNA microarray analysis showed that 14 mRNA genes and 4 miRNA genes were differentially expressed in CDCs vs. PDLSCs and PULPSCs. Conclusions: Within the limitations of the study, CDCs seem to have stemness and preferentially express CEMP1. Moreover, there were several up- or down-regulated genes in CDCs vs. PDLSCs, PULPSCs, and BMSCs and these genes could be candidate marker proteins of CDCs.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1998.05a
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• pp.22-26
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• 1998

멜론은 향기가 독특하고, 재배기간이 짧으며, 수확시의 노동력이 적게 들고, 부가가치가 높아 점차 재배면적이 늘고 있는 작물이다 멜론재배의 성패는 네트의 양호한 형성과 당도향상에 있으며 이것은 합리적인 수분관리를 통해서만 가능하고, 합리적인 수분관리를 위해서는 멜론 수분소비량의 정확한 계측이 필수적이다. (중략)

• 한국연소학회:학술대회논문집
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• 2014.11a
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• pp.191-194
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• 2014

The characteristics of laminar free jet flow with having applied AC electric fields have been investigated experimentally. A single electrode configuration was adopted such that electric fields were applied directly to nozzle and thus the surrounding could be an infinite ground. The experimental results showed that the jet flow with AC was modified significantly. At a certain axial distance, the laminar fuel stem was broken down and subsequently it was separated into three parts when AC electric fields were applied over a certain voltage in a range of frequencies less than 120 Hz. The breakdown point was measured by varying applied AC voltage and frequency. The effect of applying electric fields to jet flow was discussed in detail.

• Clinics in Shoulder and Elbow
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• v.15 no.2
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• pp.65-72
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• 2012

Purpose: To evaluate the differentiation potential of stem cells and their immunophenotype from 3 different sources. Methods: Our study involved three stem cell sources-subacromial bursal tissue, bone marrow, and umbilical cord blood. We obtained the subacromial bursal tissue and bone marrow from the patients undergoing shoulder surgery. After collecting the sample, we applied specific induction media for neurogenic, adipogenic and osteogenic differentiation. Also, flow-cytometry analysis was done to reveal the cell surface antigens. Results: We obtained 100% (8 cases) neural and adipogenic differentiation, but 62.5% (5 of 8 cases) osseous differentiation among the subacromial bursal tissue group. Bone marrow derived cells showed 100% neural (6 cases) and adipogenic (5 cases) differentiation, but 80% (4 of 5 cases) osseous differentiation. Umbilical cord blood derived cells revealed 97% (65 of 67 cases) neural, 53.7% (29 of 54 cases) adipogenic and 68.4% (39 of 57 cases) osseous differentiation. Immunophenotype analysis revealed that surface markers of bone marrow, subacromial bursal cell and umbilical cord blood derived mesenchymal stem cells are different from each other. Conclusions: Mesenchymal stem cells are potential agents in regenerative medicine and are characterized by expression of surface markers and by their differentiation potential. Our study with stem cells from subacromial bursal tissue, bone marrow and umbilical cord discovered that each stem cell has unique differentiation potential and function based on its origin. Various stem cells show multi-lineage differentiations in vitro which can be correlated to in vivo conditions.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.09b
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• pp.951-951
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• 2005

The characteristics of Boussinesq starting forced plumes were investigated in this study. Two distinct periods in the transient plume penetration were identified, namely the Period of Flow Development (PFD) and Period of Developed Flow (PDF). PFD refers to the time period whereby the penetration rate is governed by the complex vortex dynamics initiated by the exit conditions that can include vortex coalescence, vortex leapfrogging, pinching off of the head vortex from the trailing stem and the eventual reconnection. The pinch-off and reconnection leads to an overshoot of the plume front which is a common observation reported in previous studies. The penetration rate in PDF is more predictable and depends on the continuous feeding of buoyancy and momentum into the head vortex by the trailing buoyant-jet stem. Similarity solutions are developed for PDF to describe the temporal variation of the penetration rate, by incorporating the behavior of an isolated buoyant vortex ring and recent laboratory results on the trailing buoyant jet. In particular, the variations of velocity ratios between the head vortex and trailing buoyant jet are analytically computed. To verify the similarity solutions, experiments were conducted on vertical starting forced plumes using planar laser induced fluorescence (PLIF).

• Molecules and Cells
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• v.38 no.6
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• pp.548-561
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• 2015

By combining conventional single cell analysis with flow cytometry and public database searches with bioinformatics tools, we extended the expression profiling of thymic stromal cotransporter (TSCOT), Slc46A2/Ly110, that was shown to be expressed in bipotent precursor and cortical thymic epithelial cells. Genome scale analysis verified TSCOT expression in thymic tissue- and cell type- specific fashion and is also expressed in some other epithelial tissues including skin and lung. Coexpression profiling with genes, Foxn1 and Hoxa3, revealed the role of TSCOT during the organogenesis. TSCOT expression was detected in all thymic epithelial cells (TECs), but not in the $CD31^+$endothelial cell lineage in fetal thymus. In addition, ABC transporter-dependent side population and Sca-$1^+$ fetal TEC populations both contain TSCOT-expressing cells, indicating TEC stem cells express TSCOT. TSCOT expression was identified as early as in differentiating embryonic stem cells. TSCOT expression is not under the control of Foxn1 since TSCOT is present in the thymic rudiment of nude mice. By searching variations in the expression levels, TSCOT is positively associated with Grhl3 and Irf6. Cytokines such as IL1b, IL22 and IL24 are the potential regulators of the TSCOT expression. Surprisingly, we found TSCOT expression in the lung is diminished in lung cancers, suggesting TSCOT may be involved in the suppression of lung tumor development. Based on these results, a model for TEC differentiation from the stem cells was proposed in context of multiple epithelial organ formation.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.9
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• pp.3715-3721
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• 2015

Leukemia is a clonal disorder with blocked normal differentiation and cell death of hematopoietic progenitor cells. Traditional modalities with most used radiation and chemotherapy are nonspecific and toxic which cause adverse effects on normal cells. Differentiation inducing therapy forcing malignant cells to undergo terminal differentiation has been proven to be a promising strategy. However, there is still scarce of potent differentiation inducing agents. We show here that Angelica sinensis polysaccharide (ASP), a major active component in Dong quai (Chinese Angelica sinensis), has potential differentiation inducing activity in human chronic erythro-megakaryoblastic leukemia K562 cells. MTT assays and flow cytometric analysis demonstrated that ASP inhibited K562 cell proliferation and arrested the cell cycle at the G0/G1 phase. ASP also triggered K562 cells to undergo erythroid differentiaton as revealed by morphological changes, intensive benzidine staining and hemoglobin colorimetric reaction, as well as increased expression of glycophorin A (GPA) protein. ASP induced redistribution of STAT5 protein from the cytoplasm to the nucleus. Western blotting analysis further identified that ASP markedly sensitized K562 cells to exogenous erythropoietin (EPO) by activating EPO-induced JAK2/STAT5 tyrosine phosphorylation, thus augmenting the EPO-mediated JAK2/STAT5 signaling pathway. On the basis of these findings, we propose that ASP might be developed as a potential candidate for chronic myelogenous leukemia inducing differentiation treatment.

• Journal of Embryo Transfer
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• v.27 no.3
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• pp.183-187
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• 2012

Adult stem cell transplantation has been increased every year, because of the lack of organ donors for regenerative medicine. Therefore, development of reliable and safety cryopreservation and bio-baking method for stem cell therapy is urgently needed. The present study investigated safety of dimethyl sulfoxide (DMSO) such as common cryoprotectant on porcine bone marrow derived mesenchymal stem cells (pBM-MSCs) by evaluating the activation of Caspase-3 and -7, apoptosis related important signal pathway. pBM-MSCs used for the present study were isolated density gradient method by Ficoll-Paque Plus and cultured in A-DMEM supplemented 10% FBS at $38.5^{\circ}C$ in 5% $CO_2$ incubator. pBM-MSCs were cryopreserved in A-DMEM supplemented either with 5%, 10% or 20% DMSO by cooling rate at $-1^{\circ}C$/min in a Kryo 360 (planner 300, Middlesex, UK) and kept into $LN_2$. Survival rate of cells after thawing did not differ between 5% and 10% DMSO but was lowest in 20% DMSO by 0.4% trypan blue exclusion. Activation of Caspase-3 and -7 by Vybrant FAM Caspase-3 and -7 Assay Assay Kit (Molecular probes, Inc.OR, USA) was analyzed with a flow cytometer. Both of cryopreserved and control groups (fresh pBM-MSCs) were observed after the activation of Caspase-3 and -7. The activation did not differ between 5% and 10% DMSO, but was observed highest in 20% DMSO. Therefore 5% DMSO can be possibly used for cell cryopreservation instead of 10% DMSO.

• IMMUNE NETWORK
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• v.7 no.3
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• pp.117-123
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• 2007

Background: This study was designed to investigate the role of the hepatocyte growth factor (HGF) with regards to differentiation of somatic stem cells originating from the human umbilical cord blood (UCB) into hepatic lineage cells in vitro culture system. Methods: Mononuclear cells from UCB were cultured with and without HGF based on the fibroblast growth factor (FGF)-1, FGF-2, and stem cell factor. The cultured cells were confirmed by immunofluorescent staining analysis with albumin (ALB), cytokeratin-19 (CK-19), and proliferating cell nuclear antigen (PCNA) MoAb. ALB and CK-18 mRNA were also evaluated by reverse transcription-polymerase chain reaction. In order to observe changes in proliferating capacity with respect to the cultured period, CFSE with affinity to proliferating cells were tagged and later underwent flow cytometry. Results: In the HGF-treated group, cultured cells had a large oval shaped appearance with adherent, but easily detachable characteristics. In the HGF-non treated group, these cells were spindle-shaped with strong adherent characteristics. Expressions of ALB and CK-19 were evident in HGF-treated group compared to non-expression of those in to HGF-non treated group. Dual immunostaining analysis of the ALB producing cells showed presence of PCNA in their nuclei, and ALB and CK-18 mRNA were detected on the 21st day of cultured cells in the HGF-treated group. Conclusion: Our findings suggest that HGF has a pivotal role in differentiating somatic stem cells of human UCB into hepatic lineage cells in vitro.