• Molecules and Cells
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• v.44 no.11
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• pp.851-860
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• 2021

Label-free optical diffraction tomography (ODT), an imaging technology that does not require fluorescent labeling or other pre-processing, can overcome the limitations of conventional cell imaging technologies, such as fluorescence and electron microscopy. In this study, we used ODT to characterize the cellular organelles of three different stem cells-namely, human liver derived stem cell, human umbilical cord matrix derived mesenchymal stem cell, and human induced pluripotent stem cell-based on their refractive index and volume of organelles. The physical property of each stem cell was compared with that of fibroblast. Based on our findings, the characteristic physical properties of specific stem cells can be quantitatively distinguished based on their refractive index and volume of cellular organelles. Altogether, the method employed herein could aid in the distinction of living stem cells from normal cells without the use of fluorescence or specific biomarkers.

• BMB Reports
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• v.55 no.2
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• pp.65-71
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• 2022

Regenerative medicine is a research field that develops methods to restore damaged cell or tissue function by regeneration, repair or replacement. Stem cells are the raw material of the body that is ultimately used from the point of view of regenerative medicine, and stem cell therapy uses cells themselves or their derivatives to promote responses to diseases and dysfunctions, the ultimate goal of regenerative medicine. Stem cell-derived extracellular vesicles (EVs) are recognized as an attractive source because they can enrich exogenous microRNAs (miRNAs) by targeting pathological recipient cells for disease therapy and can overcome the obstacles faced by current cell therapy agents. However, there are some limitations that need to be addressed before using miRNA-enriched EVs derived from stem cells for multiplexed therapeutic targeting in many diseases. Here, we review various roles on miRNA-based stem cell EVs that can induce effective and stable functional improvement of stem cell-derived EVs. In addition, we introduce and review the implications of several miRNA-enriched EV therapies improved by multiplexed targeting in diseases involving the circulatory system and nervous system. This systemic review may offer potential roles for stem cell-derived therapeutics with multiplexed targeting.

• Development and Reproduction
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• v.13 no.4
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• pp.227-237
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• 2009

Recently, adipose mesenchymal stem cells (AdMSC) that are similar to bone marrow MSC and blood derived MSC are thought to be another source for stem cell therapy. However, the diseases that can be applied for stem cells therapy are age-dependent degenerative diseases. Accordingly, the present study investigated the growth and differentiation potential to neural cells of human AdMSC (hAdMSC) obtained from aged thirty, forty and fifty. The growth of cells and cell viability were measured by passage and neural differentiation of hAdMSC was induced in neural differentiation condition for 10 days. Our results demonstrated that cell number, viability and morphology were not different from hAdMSC by age and passage. Immunofluorescence analysis of neural cell marker (TuJ1, NSE, Sox2, GFAP or MAP2) demonstrated no significant differences in neural cell differentiation by age and passage. As the number of passage was increased, the mRNA level of MAP2 and Sox2 was decreased in hAdMSC from age of 50 compared to hAdMSC from age of 30. In conclusion, the present study demonstrated that ability of neural cell differentiation of hAdMSC was maintained with ages, suggesting that autologous stem cells from aged people can be applied for stem cell therapy with age-dependent neural disease with the same stem cell quality and ability as stem cell derived from young age.

• Journal of Korean Society of Forest Science
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• v.109 no.4
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• pp.461-467
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• 2020

The aim of this study was to utilize Kozak's stem taper model to develop both a stem taper equation and a stem volume table for Criptomeria japonica, a tree species distributed across Korea. A total of 1,000 sample trees were cut and collected across the country to measure their diameters by stem height. The equation was then used to estimate examine their stem shapes. Our results show that the Fitness Index for the equation was 98.7%, the Mean Absolute Deviation (MAD) was -0.0142, and the MAD was 1.1640, thus indicating a high level of fitness. A statistically significant difference (p < 0.05) was also found from the analysis of discrepancies between a current table and the new table used in this study. It is therefore suggested that the new table-with data from actual stands-will contribute to enhancing the accuracy of national and municipal forest statistics and reducing losses caused by imprecise data on available forest resources.

• Journal of Life Science
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• v.32 no.7
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• pp.567-577
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• 2022

Recently, the prevalence of ischemic diseases, such as ischemic heart disease, cerebral ischemia, and peripheral arterial disease, has been continuously increasing due to the aging population. The current standardized treatment for ischemic diseases is reperfusion therapy through pharmacotherapy and surgical approaches. Although reperfusion therapy may restore the function of damaged arteries, it is not effective at restoring the function of the surrounding tissues that have been damaged due to ischemia. Therefore, it is necessary to develop a new treatment strategy that can safely and effectively treat ischemic damage and restore the function of surrounding tissues. To overcome these limitations, stem cell-based therapy to regenerate the damaged region has been studied as a promising strategy for ischemic vascular diseases. Mesenchymal stem cells (MSCs) can be isolated from diverse tissues and have been shown to be promising for the treatment of ischemic disease by regenerating damaged tissues through immunomodulation, the promotion of angiogenesis, and the secretion of various relevant factors. Moreover, new approaches to enhancing MSC function, such as cell priming or enhancing transplantation efficiency using a 3D culture method, have been studied to increase stem cell therapeutic efficacy. In this review, we provide various strategies by which MSCs are used to treat ischemic diseases, and we discuss the challenges of MSC transplantation, such as the differentiation, proliferation, and engraftment of MSCs at the ischemic site.

• BMB Reports
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• v.57 no.5
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• pp.250-255
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• 2024

Due to their stem-like characteristics and immunosuppressive properties, Mesenchymal stem cells (MSCs) offer remarkable potential in regenerative medicine. Much effort has been devoted to enhancing the efficacy of MSC therapy by enhancing MSC migration. In this study, we identified deubiquitinase BRCA1-associated protein 1 (BAP1) as an inhibitor of MSC migration. Using deubiquitinase siRNA library screening based on an in vitro wound healing assay, we found that silencing BAP1 significantly augmented MSC migration. Conversely, BAP1 overexpression reduced the migration and invasion capabilities of MSCs. BAP1 depletion in MSCs upregulates ERK phosphorylation, thereby increasing the expression of the migration factor, osteopontin. Further examination revealed that BAP1 interacts with phosphorylated ERK1/2, deubiquitinating their ubiquitins, and thus attenuating the ERK signaling pathway. Overall, our study highlights the critical role of BAP1 in regulating MSC migration through its deubiquitinase activity, and suggests a novel approach to improve the therapeutic potential of MSCs in regenerative medicine.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2002.05a
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• pp.16-22
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• 2002

STEP Method(STEM)는 의사결정자와 최적화 모형간의 상호작용을 통하여 문제를 해결하는 다목적 최적화 기법이다 STEM은 최적화 모형을 계산하는 계산 단계와 계산 단계에서 도출된 결과에 대하여 의사결절자의 선호도 정보를 모형에 반영하는 의사결정 단계로 구성되어 있다. STEM의 두 단계에서는 의사결정자의 선호도 정보가 불확실성을 포함한 경우를 적절히 고려하지 못하고 있다. 본 연구에서는 퍼지모델링 기법을 사용하여 STEM의 문제점을 보완한 기법을 제안하고자 한다.

• Journal of Life Science
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• v.30 no.7
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• pp.651-659
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• 2020

Cardiovascular disease is one of the leading causes of death across the world, and gold-standard treatments such as percutaneous coronary intervention and artery bypass grafting have various limitations including myocardial damage and subsequent maladaptive cardiac remodeling. To overcome this, stem-cell therapies are emerging as a promising strategy for cardiovascular regeneration. Endothelial progenitor cells (EPCs) have high potential to proliferate and differentiate into endothelial cells for vascularization and tissue regeneration, and several clinical trials have explored EPC function in tissue repair in relation to clinical safety and improving cardiac function. Consequently, EPC has been suggested as a feasible stem-cell therapy. However, autologous EPC transplantation in cardiovascular disease patients is restricted by risk factors such as age, smoking status, and hypertension that lead to reduced bioactivity in the EPCs. New approaches for improving EPC function and stem-cell efficacy have therefore been suggested, including cell priming, organoid culture systems, and enhancing transplantation efficiency through 3D bioprinting methods. In this review, we provide a comprehensive understanding of EPC characteristics, therapeutic approaches, and the current state of clinical research into EPCs as stem-cell therapy for cardiovascular disease.

• Horticultural Science & Technology
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• v.33 no.2
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• pp.276-282
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• 2015

Seasonal variation in the contents of sugars (fructose, glucose, and sucrose) in the floret, leaf, and stem of broccoli were studied in ten commercial broccoli cultivars. Plants were grown in the spring and fall seasons in 2011. In both seasons, glucose was the major constituent, comprising about 50% of the total sugar content in the floret and leaf tissue of most cultivars, whereas the broccoli stem showed an unusual pattern of accumulation. Sucrose exhibited greater cultivar dependency as well as seasonal variation compared to fructose and glucose in floret and leaf tissues. The floret tissue had a higher total content of sugar in the spring compared to the fall due to an increase in glucose and fructose. However, most of the leaf and stem tissues of broccoli had a higher total sugar content in the fall compared to the spring. Furthermore, stem and leaf tissues possessed a relatively higher total sugar content compared to floret tissue in both seasons. 'Grandeur' broccoli contained a significantly greater amount of total sugar in both floret and leaf tissues in both seasons, whereas 'YuDoRi No.1' broccoli exhibited the highest total content of sugar in stem tissue. At overall, the results showed significant influences of genotype, plant part and growing season on sugar content in broccoli.

• Journal of Microbiology and Biotechnology
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• v.32 no.12
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• pp.1615-1621
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• 2022

Tissue regeneration is the ultimate treatment for many degenerative diseases, however, repair and regeneration of damaged organs or tissues remains a challenge. Previously, we showed that B1 Ab and H3 Ab induce stem cells to differentiate into microglia and brown adipocyte-like cells, while trafficking to the brain and heart, respectively. Here, we present data showing that another selected agonist antibody, P1 antibody, induces the migration of cells to the pancreatic islets and differentiates human stem cells into beta-like cells. Interestingly, our results suggest the purified P1 Ab induces beta-like cells from fresh, human CD34⁺ hematopoietic stem cells and mouse bone marrow. In addition, stem cells with P1 Ab bound to expressed periostin (POSTN), an extracellular matrix protein that regulates tissue remodeling, selectively migrate to mouse pancreatic islets. Thus, these results confirm that our in vivo selection system can be used to identify antibodies from our library which are capable of inducing stem cell differentiation and cell migration to select tissues for the purpose of regenerating and remodeling damaged organ systems.