• 농업과학연구
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• 제24권1호
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• pp.6-10
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• 1997

초장, 엽수, 경수, 경직경, 엽장, 엽폭, 근경생산량을 평가하기위하여 수집 한 94 clone은 경수와 근경생산량에서 유용한 변이를 보여주었다. 초장, 엽수, 엽장, 엽폭, 경직경은 약간의 변이가 관찰되었다. 작물학적 특성간의 단순상관은 근경생산량과 정의 상관을 보여주었고 엽수, 초장, 경직경은 근경생산량과 고도의 정의 상관을 보여주었다. 경로계수분석을 통하여 경수, 엽수, 경직경순으로 근경생산에 직접효과를 준다는 결과를 얻을 수 있었다. 엽수를 통한 초장의 간접효과가 가장 크게 나타났고, 엽수를 통한 엽장, 엽폭과 경직경을 통한 초장, 엽장, 엽폭에서도 간접효과가 관찰되었다. 선발의 관점에서 볼 때, 초장, 엽수, 경수와 같은 특성들은 좋은 유전형을 선발하기에 적합하다고 여겨진다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제40권4호
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• pp.173-180
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• 2014

Objectives: The purpose of this study was to investigate the neurogenic differentiation of human dental pulp stem cells (DPSCs), periodontal ligament stem cells (PDLSCs), and stem cells from apical papilla (SCAP). Materials and Methods: After induction of neurogenic differentiation using commercial differentiation medium, expression levels of neural markers, microtubule-associated protein 2 (MAP2), class III ${\beta}$-tubulin, and glial fibrillary acidic protein (GFAP) were identified using reverse transcriptase polymerase chain reaction (PCR), real-time PCR, and immunocytochemistry. Results: The induced cells showed neuron-like morphologies, similar to axons, dendrites, and perikaryons, which are composed of neurons in DPSCs, PDLSCs, and SCAP. The mRNA levels of neuronal markers tended to increase in differentiated cells. The expression of MAP2 and ${\beta}$-tubulin III also increased at the protein level in differentiation groups, even though GFAP was not detected via immunocytochemistry. Conclusion: Human dental stem cells including DPSCs, PDLSCs, and SCAP may have neurogenic differentiation capability in vitro. The presented data support the use of human dental stem cells as a possible alternative source of stem cells for therapeutic utility in the treatment of neurological diseases.

• Clinical and Experimental Reproductive Medicine
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• 제35권4호
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• pp.247-265
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• 2008

목 적: 사람의 제대유래 줄기세포 (HUC)와 양막유래 줄기세포 (HAM)를 간유사세포로 분화 시키고자 하였다. 연구방법: 산모의 동의아래 만삭 정상 산모로부터 양막 및 제대를 얻고 줄기세포를 분리, 배양하였다. 분리된 세포의 줄기세포로서의 특성을 규명하기 위하여 RT-PCR, 세포면역화학 분석 그리고 중배엽성세포로의 분화능 실험을 하였다. 또한 이들 줄기세포를 분화 배양액에서 간유사세포로 분화 유도 후, 간세포 특이 유전자 발현, 알부민 ELISA, 알부민에 대한 면역블로팅 및 세포면역화학염색 그리고 PAS 염색을 시행하였다. 결 과: 사람의 양막 및 제대로부터 세포를 분리하여 줄기세포로서의 특성을 조사하고, 이들 세포의 지방세포, 연골세포, 골아세포로의 분화능력을 확인하였다. 동일한 분화 배양액에서 HUC과 HAM을 간유사세포로 분화시킨 결과 HUC이 모든 조건에서 HAM보다 알부민과 요소를 더 많이 합성 분비하였다. 간유사세포로의 분화능력이 더 좋은 것으로 나타난 HUC을 가지고 최적의 분화를 유도한 결과 $1.2{\pm}0.8\;{\mu}g/mL$의 알부민을 합성 분비하였고, $8.9{\pm}1.2\;mg/dL$의 요소를 합성 분비하였다. 결 론: HUC과 HAM 모두 알부민을 분비하는 간유사세포로 분화할 수 있었으며, HUC이 더 잘 유도되는 것으로 관찰되었다. 이러한 결과로써 HUC과 HAM을 간질환 환자의 간세포 이식 치료에 필요한 세포치료제로써 이용할 수 있을 것으로 생각된다.

• Clinical and Experimental Reproductive Medicine
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• 제29권1호
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• pp.1-12
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• 2002

Objective: In order to acquire the technique for the establishment of human embryonic stem cells (ESe) derived from the human frozen-thawed embryos produced in IVF-ET program, this study was performed to establish mouse ESC derived from the in vitro fertilized embryos. Materials and Methods: After Fl hybrid (C57BL female $\times$ CBA mael) female mice were superovulated with PMSG and hCG treatment, their oocytes were retrieved and inseminated, and the fertilized embryos were cultured for 96-120 hours until the expected stages of blastocysts were obtained. To isolate the inner cell mass (ICM), either the blastocysts were treated with immunosurgery, or the whole embryos were cultured for 4 days. Isolated ICMs were then cultured onto STO feeder cell layer, and the resultant ICM colonies were subcultured with trypsin-EDTA treatment. During the subculture process, ESC-like cell colonies were observed with phase contrast microscopy. To identify ESC in the subcultured ESC-like cell colonies, alkaline phosphatase activity and Oct-4 (octamer-binding transcription factor-4) expression were examined by immunohistochemistry and RT-PCR, respectively. To examine the spontaneous differentiation, ESC-like cell colonies were cultured without STO feeder cell layer and leukemia inhibitory factor (LIF). Results: Seven ESC-like cell lines were established from ICMs isolated from the in vitro fertilized embryos. According to the developmental stage, the growth of ICMs isolated from the expanded blastocysts was significantly better than that of ICMs isolated from the hatched blastocysts (80.3% vs. 58.7%, p<0.05). ESC-like cell colonies were only obtained from ICMs of expanded blastocysts. However, the ICMs isolated from the embryos treated with immunosurgery were poorly grown and frequently differentiated during the culture process. The established ESC-like cell colonies were positively stained with alkaline phosphatase and expressed Oct-4, and their morphology resembled that observed in the previously reported mouse ESC. In addition, following the extended in vitro culture process, they maintained their expression of cell surface markers characteristic of the pluripotent stem cells such as alkaline phosphatase and Oct-4. When cultured without STO feeder cell layer and LIF, they were spontaneously differentiated into the various types of cells. Conclusion: The findings of this study suggest that the establishment of mouse ESC can be successfully derived from the in vitro fertilized embryos. The established ESC-like cells expressed the cell surface markers characteristic of the pluripotent stem cells and spontaneously differentiated into the various types of cells.

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2003년도 학술발표대회 발표논문초록집
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• pp.76-76
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• 2003

Pluripotent embryonic stem cells can differentiate into beating cardiomyocytes with proper culture conditions and stimulants via embryo-like aggregates. We describe here the use of mouse embryonic stem (mES03) cells as a reproducible differentiation system for cardiomyocyte. mES03 cells growing in colonies were dissociated and allowed to re-aggregated in suspension [embryoid body (EB) formation〕. To induce cardiomyocytic differentiation, cells were exposed to 0.75% dimethyl sulfoxide (DMSO) during EB formation for 4 days and then another 4 days without DMSO (4+/4-). Thus treated EB was plated onto gelatin-coated dishes for differentiation. Spontaneously contracting colonies which appeared in approximately 4~5 days upon differentiation were mechanically dissected, enzymatically dispersed, plated onto coverslips, and then incubated for another 48~72 hrs. By RT-PCR, robust expression of cardiac myosin heavy chain $\alpha$, cardiac muscle heavy polypeptide 7 $\beta$($\beta$-MHC), cardiac transcription factor GATA4, and skeletal muscle-specific $\alpha$$_1$-subunit of the L-type calcium channel ($\alpha$$_1$CaC $h_{sm}$ ) were detected as early as 8 days after EB formation, but message of cardiac muscle-specific $\alpha$$_1$-subunit of the L-type calcium channel ($\alpha$$_1$CaCh) were reveled at a low level. In contrast, expression of myosin light chain (MLC-2V) and atrial natriuretic factor (ANF) were not detected during EB formation for 8 days. However, a strong expression of the atrial-specific ANF gene was expressed from day 8 onward, which were remained constant in EB. (cardiac specialization and terminal differentiation stage). Electrophysiological examination of spontaneously contracting cells showed ventricle-like action potential 17 days after the EB formation. This study indicates that mES03 cell-derived cardiomyocytes via 4+/4- protocol displayed biochemical and electrophysiological properties of subpopulation of cardiomyocytes.

• 마이크로전자및패키징학회지
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• 제7권1호
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• pp.25-28
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• 2000

분자선에피택시법에 의하여 GaAs(100)기판 위에 InAs 자발형성양자점을 성장하였다. InAs 양자점은 1, 3, 6, 10, 15 및 20층 등으로 다양하게 적층되어졌고, GaAs 층과 InAs 양자점 층은 각각 20 MLs와 2 MLs의 두께를 갖도록 하였다. 이 양자점의 나노구조적 특성은 PL과 STEM을 사용하여 분석하였다. 가장 높은 PL 강도는 6층의 적층구조를 갖는 시편에서 나타났고 PL 피크의 에너지가 적층회수가 증가함에 따라 분리됨을 알 수 있었다. STEM분석결과, 6충의 적층구조에서는 결함이 거의 없이 수직으로 형성된 구조를 보여준 반면에 10층 이상의 적층구조를 가질 때 그 성장 방향에 따라 volcano형상을 갖는 결함이 수직하게 성장되어졌다.

• 분석과학
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• 제31권6호
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• pp.232-239
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• 2018

Human breast milk (HBM) provides neonates with indispensable nutrition. The present study evaluated the anti-cancer activity of diluted and pasteurized early HBM (< 6 weeks' lactation) on human breast cancer cell lines. The cell lines MCF7 and MDA-MB231 were exposed to 1 % HBM from the 1st, 3rd, and 6th weeks of lactation and exhibited reduced proliferation rates. As controls, breast cell lines (293T and MCF-10A), breast cancer cell lines (MCF-7 and MDA-MB-231), and $CD133^{hi}CXCR4^{hi}ALDH1^{hi}$ patient-derived human cancer stem-like cells (KU-CSLCs) were treated with prominent milk proteins ${\beta}$-casein, ${\kappa}$-casein, and lactoferrin at varying doses (10, 50, and $100{\mu}g$) for 24 or 48 hrs. The impact of these proteins on cell proliferation was investigated. Breast cancer cell lines treated with ${\kappa}$-casein and lactoferrin exhibited significantly reduced viability, in both a dose- and time-dependent manner. Interestingly, ${\kappa}$-casein selectively impacted only cancer (but not normal breast) cell lines, particularly the more malignant cell line. However, ${\beta}$-casein-exposed human breast cancer cell lines exhibited a significantly higher proliferation rate. Thus, ${\kappa}$-casein and lactoferrin appear to exert selective anti-cancer activities. Further studies are warranted to determine the mechanisms underlying ${\kappa}$-casein- and lactoferrin-mediated cancer cell-selective cytotoxic effects.

• Asian Pacific Journal of Cancer Prevention
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• 제14권10호
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• pp.5705-5711
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• 2013

Background: Embryonic stem cells (ESCs) have the potential to form teratomas when implanted into immunodeficient mice, but data in immunocompetent mice are limited. We therefore investigated teratoma formation after implantation of three different mouse ESC (mESC) lines into immunocompetent mice. Materials and Methods: BALB/c mice were injected with three highly germline competent mESCs (129Sv, BALB/c and C57BL/6) subcutaneously or under the kidney capsule. After 4 weeks, mice were euthanized and examined histologically for teratoma development. The incidence, size and composition of teratomas were compared using Pearson Chi-square, t-test for dependent variables, one-way analysis of variance and the nonparametric Kruskal-Wallis analysis of variance and median test. Results: Teratomas developed from all three cell lines. The incidence of formation was significantly higher under the kidney capsule compared to subcutaneous site and occurred in both allogeneic and syngeneic mice. Overall, the size of teratoma was largest with the 129Sv cell line and under the kidney capsule. Diverse embryonic stem cell-derived tissues, belonging to the three embryonic germ layers, were encountered, reflecting the pluripotency of embryonic stem cells. Most commonly represented tissues were nervous tissue, keratinizing stratified squamous epithelium (ectoderm), smooth muscle, striated muscle, cartilage, bone (mesoderm), and glandular tissue in the form of gut- and respiratory-like epithelia (endoderm). Conclusions: ESCs can form teratomas in immunocompetent mice and, therefore, removal of undifferentiated ESC is a pre-requisite for a safe use of ESC in cell-based therapies. In addition the genetic relationship of the origin of the cell lines to the ability to transplant plays a major role.

• 생명과학회지
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• 제26권7호
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• pp.835-846
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• 2016

항암제 내성은 화학적 치료법의 가장 큰 난관의 하나로 효과적인 항암치료를 위해서 반드시 극복 되야 할 문제이다. ABCG2는 다약제 내성과 이를 특징으로 하는 암 줄기세포와의 연관성도 매우 높다고 보고되고 있다. 최근 암용해 바이러스가 다양한 암종과 항암제내성을 보이는 암 치료에 새로운 대안으로 대두되고 있다. 이에 본 연구에서는 항암제 내성 암 치료를 위해 새로운 암용해 백시니아 바이러스 SLJ-496을 개발하였다. 본 연구에서, cytophathic effect, plaque assay, viability assay를 통하여 야생형 바이러스에 비교하여 증가된 종양친화성을 확인하였다. 또한, invitro 환경에서 대장암 세포주(HT-29, HCT-116, HCT-8)를 비롯하여 위암 세포주(AGS, NCI-N87, MKN-28), 간암 세포주(SNU-449, SNU-423, SNU-475, HepG2) 그리고 난치성 암 종인 중피 세포종(NCI-H226, NCI-H28, MSTO-211h)에서 유의적인 세포독성효능을 입증하였다. ABCG2의 발현이 높은 HT-29세포의 3차원 구형배양을 통하여 ABCG2와 암줄기세포 특성의 연관성을 증명하였으며, 항암제 내성세포 모델에서 SLJ-496GFP가 유의한 세포독성을 나타내며 암세포내 복제능을 가지는 것을 입증하였다. ABCG2를 과발현 시킨 세포주 내 야생형 바이러스에 비교하여 유의적으로 낮은 세포 생존율을 증명하였으며, 바이러스의 복제능 또한 검증하였다. 또한, 지속적인 항암제 투여를 통하여 ABCG2의 발현이 높은 항암제 내성 세포주에서의 항종양 효능 또한 입증하였다. 이상의 결과를 토대로 ABCG2가 과발현 된 암 줄기세포 및 항암제 내성에 새로운 항종양 바이러스 SLJ-496 백시니아 바이러스 치료법이 새로운 치료 대안이 될 수 있을 것이라 제안한다.

• BMB Reports
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• 제49권12호
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• pp.655-661
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• 2016

Polymer brush is a soft material unit tethered covalently on the surface of scaffolds. It can induce functional and structural modification of a substrate's properties. Such surface coating approach has attracted special attentions in the fields of stem cell biology, tissue engineering, and regenerative medicine due to facile fabrication, usability of various polymers, extracellular matrix (ECM)-like structural features, and in vivo stability. Here, we summarized polymer brush-based grafting approaches comparing self-assembled monolayer (SAM)-based coating method, in addition to physico-chemical characterization techniques for surfaces such as wettability, stiffness/elasticity, roughness, and chemical composition that can affect cell adhesion, differentiation, and proliferation. We also reviewed recent advancements in cell biological applications of polymer brushes by focusing on stem cell differentiation and 3D supports/implants for tissue formation. Understanding cell behaviors on polymer brushes in the scale of nanometer length can contribute to systematic understandings of cellular responses at the interface of polymers and scaffolds and their simultaneous effects on cell behaviors for promising platform designs.