Kyung-hee Choi

Embryonic stem cell-derived embryoid bodies contain a unique precursor population which, in response to vascular endothelial growth factor, gives rise to blast colonies in semi-solid medium. Upon transfer to liquid culture with appropriate cytokines, these blast colonies generate both hematopoietic and adherent, stromal-type cells. Cells within the adherent population display characteristics of endothelial lineage including the expression of CD31, flk-1, flt-1, tie-2, the capacity to take up ace

In the developing embryo, the initial hematopoietic and vascular structure can be identified as the blood islands of the yolk sac. Blood islands are formed from mesodermal aggregates that have migrated from the primitive streak. The outer cells differentiate into endothelial cells and the inner to primitive blood. The close developmental association between hematopoietic and endothelial cell lineages has led to a hypothesis that they share a common progenitor, the hemangioblast. This review will

Hematopoietic and endothelial cell lineages are the first to mature from mesoderm in the developing embryo. However, little is known about the molecular and (or) cellular events leading to hematopoietic commitment. The recent applications of technology utilizing gene targeted mice and the employment of many available in vitro systems have facilitated our understanding of hematopoietic establishment in the developing embryo. It is becoming clear that embryonic hematopoiesis occurs both in the ext

The transcription factor nuclear factor κB (NF-κB) plays a crucial role in immune and inflammatory response, and protects cells from apoptosis. In this report, we investigate whether the NF-κB signaling pathway is blocked during apoptosis induced by 2,3-dichloro-5,8-dihydroxy-1,4-naphthoquinone (NA), an analog of naphthoquinone. It is observed that NA triggers apoptotic cell death in HeLa cells and destroys resistance to apoptosis caused by tumor necrosis factor-α. Data presented in this study e

Myct1 inhibition controls tumor angiogenesis, remodels tumor immunity, and improves immunotherapy outcomes in mouse tumor models.

The nuclear factor-κB (NF-κB) family is involved in the expressions of numerous genes, in development, apoptosis, inflammatory responses, and oncogenesis. In this study we identified four NF-κB target genes that are modulated by TIP60. We also found that TIP60 interacts with the NF-κB RelA/p65 subunit and increases its transcriptional activity through protein-protein interaction. Although TIP60 binds with RelA/p65 using its histone acetyltransferase domain, TIP60 does not directly acetylate RelA

이 연구의 목적은 중학교 과학 수업에서 교사와 학생간의 언어적 상호작용이 실제로 어떻게 이루어지고 있는지를 관찰분석하여 이에 대한 특징을 추출함으로써 과학수업에서 교사와 학생간의 언어적 상호작용에 대한 기초 자료를 제공하는데 있다. 이를 위해 수업 분석 준거를 개발하였으며, 8명의 과학 교사의 수업 12차시를 관찰 및 녹화하였으며, 교사와의 면담을 실시하였다. 수업 분석 결과, 관찰한 과학 수업에서 교사와 학생간의 언어적 상호작용은 주로 교사의 단순 확인/기억 질문, 학생의 단답형 응답, 교사의 즉각적 피드백이 주를 이루었다. 교사가 사고 질문을 하고 지연 피드백을 부여 하는 경우 학생들이 자신의 생각을 드러내고 이를 기반으로 사고를 진전시켜 나갈 수 있었으나 이러한 사례는 그 수가 상당히 적었다. 교사들은 학생들의 사고를 유발하고 이를 진전시키기 위한 노력보다는 수업 내용을 논리적 흐름에 맞추어 체계적으로 제시하는 것에 더 큰 중점을 두는 경향이 있었다. 또한 관찰한 수업에서 교사

Abstract The ETS transcription factor Etv2 is necessary and sufficient for the generation of hematopoietic and endothelial cells. However, upstream regulators of Etv2 in hemangiogenesis, generation of hematopoietic and endothelial cells, have not been clearly addressed. Here we track the developmental route of hemangiogenic progenitors from mouse embryonic stem cells, perform genome-wide CRISPR screening, and transcriptome analysis of en route cell populations by utilizing Brachyury , Etv2 , or

p73beta is a structural and functional homologue of p53, a tumor suppressor gene. In this study, we identified a novel p73beta-binding protein, p19ras, by the yeast two-hybrid screening method. Alternative splicing of the proto-oncogene H-ras pre-mRNA has led to two distinct transcripts, p19ras and p21ras. In both endogenous and overexpressed systems, we confirmed that p19ras binds to full-length p73beta in vivo and in vitro. Coexpression of p19ras with p73beta stimulated the transcriptional act