• 제목/요약/키워드: Stem factor

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Top 50 cited articles on dental stem cell research

  • Kodonas, Konstantinos;Fardi, Anastasia;Gogos, Christos;Economides, Nikolaos
    • Restorative Dentistry and Endodontics
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    • 제45권2호
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    • pp.17.1-17.10
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    • 2020
  • Objectives: Citation analysis provides a unique insight into how scientific interests and research trends have changed over time. The aim of this study was to report on the 50 top-cited papers in dental stem cell research using the Science Citation Index Expanded provided by the Web of Science database to determine the academic importance of each contribution. Materials and Methods: After the screening, article title and type, total citations and citations per year, publication journal, publication year, first and senior authors, country of origin, institution, and university of reprint author were documented for the 50 top-cited articles in dental stem cell research. Keyword analysis was performed to determine which keywords were most/least popular. Results: Top 50-cited articles were cited between 179 to 2,275 times. The majority of papers were published in 2008 and originated from the United States with the highest contribution from the National Institute of Dental & Craniofacial Research. Journal of Dental Research published the highest number of top-cited articles, followed by Stem Cells and Journal of Endodontics. The greatest number of articles was published by two individual authors, Shi and Gronthos. Among 197 unique keywords, dental pulp stem cells and mesenchymal stem cells were the most frequently used. Thirty-eight of the 50 most cited articles were original articles, and 37 of them were in the field of basic science. Conclusions: Basic science studies in dental stem cell research published in high impact factor journals had the highest citation rates.

삼차신경통 환자의 감마나이프 수술 시 섹터블록 사용의 유용성 평가 (The Usefulness of Sector Blocks in Gamma Knife Surgery with Trigeminal Neuralgia)

  • 정창영;백금문;우성호;김명준;황정호;이현비;김호성
    • 방사선산업학회지
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    • 제12권4호
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    • pp.337-341
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    • 2018
  • Sector block is not used for Gamma Knife surgery in patients with generalized trigeminal neuralgia but sector block is used to reduce the dose reaching the brain stem when the trigeminal ganglgia and the 'Brain stem', radiation sensitive tissue, are adjacent. In the Gamma Knife surgical plan of this study, a surgical plan was established using a Leksell Gamma Plan 11. 1.0 (Elekta Instrument AB, Sweden) with one patient (Block unused, Brain stem dose No volume over 12 Gy, Case 1) who did not need a sector block and four patients (Block unused, Brain stem dose 12 Gy or more, Case 2~5) with a sector block. Magnetic resonance images were obtained by MPRAGE T1 and CISS Respectively. When the trigeminal ganglion is in close proximity to the brain stem, the brain stem volume is decreased when the sector block is used, while the treatment time was increased. In conclusion, This Study evaluates the usefulness of the Sector block in brain stem through Gamma Knife surgery in trigeminal neuralgia, which is considered to be the most important factor for the Gamma Knife surgery.

고등학생들을 위한 이공계 진로동기 검사도구 개발 및 타당화 (The Development and Validation of Instrument for Measuring High School Students' STEM Career Motivation)

  • 신세인;하민수;이준기
    • 한국과학교육학회지
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    • 제36권1호
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    • pp.75-86
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    • 2016
  • 이공계 진로동기는 지속가능한 과학기술 인력의 양성에 있어 핵심적 역할을 하며, 과학학습동기에도 큰 영향을 미친다고 알려져 왔다. 이 연구의 목적은 학생들의 이공계 진로동기를 측정할 수 있는 검사 도구를 개발 및 타당화하는데 있다. 검사도구 개발의 첫 번째 절차로 사회인지진로이론(SCCT)에 기초하여 고등학생들의 이공계 진로동기의 7개의 구인인 교육, 직업가치, 이공계 교과 자아효능감, 이공계진로 자아효능감, 이공계 진로에 대한 흥미, 부모의지지, 이공계 진로 동기로 설정하였다. 각 구인들을 측정할 수 있는 예비문항의 개발 후 고등학교 1학년 학생 767명에게 투입하였다. 학생들의 응답 자료를 바탕으로 라쉬모델 분석, 탐색적 요인분석과 구조방정식 분석을 바탕으로 한 확인적 요인분석과 다중집단 요인분석을 수행하였다. 결과적으로 Messick(1995)이 제안한 6가지 측면의 타당도 중 내용 타당도, 실제적 타당도, 구조적 타당도, 일반화 타당도가 검증되었다. 또한 구조방정식 분석을 통해 이공계 진로동기의 구인간의 연결 구조를 확인하였다. 개발된 이공계 진로동기 검사도구는 고등학교 1학년 직업진로지도에 유용한 도구로 사용될 것으로 전망된다.

Isolation and Identification of Prepubertal Buffalo (Bubalus bubalis) Spermatogonial Stem Cells

  • Feng, Wanyou;Chen, Shibei;Do, Dagiang;Liu, Qinyou;Deng, Yanfei;Lei, Xiaocan;Luo, Chan;Huang, Ben;Shi, Deshun
    • Asian-Australasian Journal of Animal Sciences
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    • 제29권10호
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    • pp.1407-1415
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    • 2016
  • Isolation and culture of spermatogonial stem cells (SSCs) are attractive for production of genetic modified offspring. In the present study, buffalo spermatogonial stem-like cells were isolated, cultured and expression pattern of different germ cell marker genes were determined. To recover spermatogonia, testes from age 3 to 7 months of buffalo were decapsulated, and seminiferous tubules were enzymatically dissociated. Two types of cells, immature sertoli cell and type A spermatogonia were observed in buffalo testes in this stage. Germ cell marker genes, OCT3/4 (Pou5f1), THY-1, c-kit, PGP9.5 (UCHL-1) and Dolichos biflorus agglutinin, were determined to be expressed both in mRNA and protein level by reverse transcription polymerase chain reaction and immunostaining in buffalo testes and buffalo spermatogonial stem-like cells, respectively. In the following, when the isolated buffalo buffalo spermatogonial stem-like cells were cultured in the medium supplemented 2.5% fetal bovine serum and 40 ng/mL glial cell-derived neurotrophic factor medium, SSCs proliferation efficiency and colony number were significantly improved than those of other groups (p<0.05). These findings may help in isolation and establishing long term in vitro culture system for buffalo spermatogonial stem-like cells, and accelerating the generation of genetic modified buffaloes.

줄기세포와 생식세포에서 리프로그래밍 인자에 대한 최근 연구 동향과 전망 (Current Progress and Prospects of Reprogramming Factors - Stem Cells vs Germ Cells -)

  • 서유미;이경아
    • 한국발생생물학회지:발생과생식
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    • 제14권2호
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    • pp.43-50
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    • 2010
  • 최근에 체세포 리프로그래밍 기법을 사용하여 체세포에 몇 가지 전사인자(리프로그래밍 인자)를 넣어줌으로써 유도만능줄기세포(induced pluripotent stem cell, iPS)를 만드는데 성공하였다. 유도만능줄기세포는 배아줄기세포와 유사하게 자가재생 할 수 있는 능력이 있으며, 신체의 모든 타입의 세포로 분화할 수 있는 특징을 가지고 있다. 배아줄기세포와는 달리 면역거부반응이 없다는 점과 윤리적인 문제로부터 자유롭다는 장점이 있어 2006년 Yamanaka 팀이 유도만능줄기세포에 관해 처음 보고한 이후로 이 분야 연구의 급속한 발전이 이루어지고 있다. 하지만 안전성의 문제점 때문에 세포치료제로 사용되기 위해서는 리프로그래밍 인자의 도입 방법 및 새로운 리프로그래밍 인자의 발굴 등 몇 가지 해결해야 할 점들이 남아 있다. 본 종설에서는 유도만능줄기세포를 만드는데 사용된 몇 가지 리프로그래밍 인자에 대해 보고된 연구 내용을 리프로그래밍 인자가 존재하는 세포인 배아줄기세포 및 난자와 배아에서 정리하고자 하며, 리프로그래밍 인자의 연구에 관한 방향에 대해 논의하고자 한다.

조혈모세포 이식을 받은 소아 환자에서 cyclosporine의 집단 약동학 분석 (Population Pharmacokinetics of Cyclosporine after Hematopoietic Stem Cell Transplantation in Pediatric Patients)

  • 조소연;강원구;이정;김재연;안숙희;곽혜선
    • 한국임상약학회지
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    • 제28권1호
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    • pp.24-29
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    • 2018
  • Background: Cyclosporine is an immunosuppressive agent used to treat and prevent graft versus host reaction (GVHR)-a complication associated with stem cell transplantation. This study aimed to develop a population pharmacokinetic model of cyclosporine and investigate factors affecting cyclosporine clearance in pediatric hematopoietic stem cell transplant patients. Methods: A total of 650 cyclosporine concentrations recorded in 65 patients who underwent hematopoietic stem cell transplantation were used. Data including age, sex, weight, height, body surface area (BSA), type of disease, chemotherapy before stem cell transplantation, type of donor, serum creatinine levels, total bilirubin concentration, hematocrit value, and type of concomitant anti-fungal agents and methylprednisolone used were retrospectively collected. Data related to cyclosporine dosage, administration time, and blood concentration were also collected. All data were analyzed using the non-linear mixed effect model; a two-compartment model with first-order elimination was used. Results: The population pharmacokinetic model of cyclosporine using the NONMEM program was as follows: $CL(L/h)=5.9{\times}(BSA/1.2)^{0.9}$, V2 (L) = 54.5, Q (L/h) = 3.5, V3 (L) = 1080.0, $k_a(h^{-1})=0.000377$. BSA was selected as a covariate of cyclosporine clearance, which increased with an increase in BSA. Conclusion: A population pharmacokinetic model for Korean pediatric hematopoietic stem cell transplant patients was developed, and the important factor affecting cyclosporine clearance was found to be BSA. The model might contribute to the development of the most appropriate dosing regimen for cyclosporine. Further studies on population pharmacokinetics should be carried out, prospectively targeting pediatric patients.

누드 마우스에서 Poly(D,L-lactic-co-glycolic acid) (PLGA) 지지체 내 인체 지방줄기세포의 골성분화 (Osteogenic Differentiation of Human Adipose-derived Stem Cells within PLGA(Poly(D,L-lactic-co-glycolic acid)) Scaffold in the Nude Mouse)

  • 유결;조성돈;변준희;이종원
    • Archives of Plastic Surgery
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    • 제34권2호
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    • pp.141-148
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    • 2007
  • Purpose: The object of this study was to evaluate the development of continuous osteogenic differentiation and bone formation after the subcutaneous implantation of the tissue-engineered bone, in vitro. Methods: Human adipose-derived stem cells were obtained by proteolytic digestion of liposuction aspirates. Adipose-derived stem cells were seeded in PLGA scaffolds after being labeled with PKH26 and cultured in osteogenic differentiation media for 1 month. The PLGA scaffolds with osteogenic stimulated adipose-derived stem cells were implanted in subcutaneous layer of four nude mice. Osteogenesis was assessed by RT-PCR for mRNA of osteopontin and bone sialoprotein(BSP), and immunohistochemistry for osteocalcin, and von Kossa staining for calcification of extracellular matrix at 1 and 2 months. Results: Implanted PLGA scaffold with adipose-derived stem cells were well vascularized, and PLGA scaffolds degraded and were substituted by host tissues. The mRNA of osteopontin and BSP was detected by RT-PCR in both osteogenic stimulation group and also osteocalcin was detected by immunohistochemistry at osteogenic stimulation 1 and 2 months, but no calcified extracellular deposit in von Kossa stain was found in all groups. Conclusion: In vivo, it could also maintain the characteristics of osteogenic differentiation that adipose-derived stem cells within PLGA scaffold after stimulation of osteogenic differentiation in vitro, but there were not normal bone formation in subcutaneous area. Another important factor to consider is in vivo, heterologous environment would have negative effect on bone formation as.[p1]

Induction of a Neuronal Phenotype from Human Bone Marrow-Derived Mesenchymal Stem Cells

  • Oh, Soon-Yi;Park, Hwan-Woo;Cho, Jung-Sun;Jung, Hee-Kyung;Lee, Seung-Pyo;Paik, Ki-Suk;Chang, Mi-Sook
    • International Journal of Oral Biology
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    • 제34권4호
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    • pp.177-183
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    • 2009
  • Human mesenchymal stem cell (hMSCs) isolated from human adult bone marrow have self-renewal capacity and can differentiate into multiple cell types in vitro and in vivo. A number of studies have now demonstrated that MSCs can differentiate into various neuronal populations. Due to their autologous characteristics, replacement therapy using MSCs is considered to be safe and does not involve immunological complications. The basic helix-loop-helix (bHLH) transcription factor Olig2 is necessary for the specification of both oligodendrocytes and motor neurons during vertebrate embryogenesis. To develop an efficient method for inducing neuronal differentiation from MSCs, we attempted to optimize the culture conditions and combination with Olig2 gene overexpression. We observed neuron-like morphological changes in the hMSCs under these induction conditions and examined neuronal marker expression in these cells by RTPCR and immunocytochemistry. Our data demonstrate that the combination of Olig2 overexpression and neuron-specific conditioned medium facilitates the neuronal differentiation of hMSCs in vitro. These results will advance the development of an efficient stem cell-mediated cell therapy for human neurodegenerative diseases.