Chung-Ang University

About: Chung-Ang University is a education organization based out in Seoul, South Korea. It is known for research contribution in the topics: Population & Thin film. The organization has 13381 authors who have published 26978 publications receiving 416735 citations. The organization is also known as: CAU & Chung.

FOXL2 interacts with steroidogenic factor-1 (SF-1) and represses SF-1-induced CYP17 transcription in granulosa cells.

Abstract: Mutations in FOXL2 are responsible for blepharophimosis-ptosis-epicanthus inversus syndrome (BPES) type I, in which affected women exhibit premature ovarian failure. FOXL2-null mice showed defects in granulosa cell development during folliculogenesis. We screened a rat ovarian yeast two-hybrid cDNA library to identify FOXL2-interacting proteins and found steroidogenic factor-1 (SF-1). Here, we show that human FOXL2 and SF-1 proteins interact in human granulosa cells and that FOXL2 negatively regulates the transcriptional activation of a steroidogenic enzyme, CYP17, by SF-1. Furthermore, FOXL2 mutants found in blepharophimosis-ptosis-epicanthus inversus syndrome type I patients lost the ability to repress CYP17 induction mediated by SF-1. Chromatin immunoprecipitation and EMSA results further revealed that FOXL2 inhibited the binding of SF-1 to the CYP17 promoter, whereas the FOXL2 mutants failed to block this interaction. Therefore, this study identifies a novel regulatory role for FOXL2 on a key steroidogenic enzyme and provides a possible mechanism by which mutations in FOXL2 disrupt normal ovarian follicle development.

Accuracy and Reliability of Length Measurements on Three-Dimensional Computed Tomography Using Open-Source OsiriX Software

Abstract: There is a growing interest in three-dimensional computed tomography (3D-CT) as a research tool for the study of bone, joint anatomy, and kinematics. However, when CT data are processed and handled manually using image processing programs to yield 3D image and coordinate value, systematic and random errors should be validated. We evaluated the accuracy and reliability of length measurement on CT with OsiriX software. 3D-CT scans were made of 14 frozen pig knees with five transosseous holes in the metaphyseal portion of femur. The lengths between tunnel orifices were measured using Mitutoyo Digimatic digital calipers to establish the gold standard, and with the OsiriX program in 3D multi-planar reformatting mode for comparison. All measurements were recorded by a principal (replicate 1, trial 1) and a secondary observer (replicate 2, trial 1) and were repeated once by each observer (trial 2). The mean differences between OsiriX and real measurements were less than 0.1 mm in both replicates, and maximum differences were less than 0.3 mm. There were no significant differences between the replicates and real measurements (p = 0.544 and 0.622 for replicates 1 and 2, respectively). The intraclass correlation coefficients (ICC) were very high between trials and between replicates (ICC = 0.998 and 0.999, respectively). For kinematic analysis of the knees, length measurements on 3D-CT using OsiriX program can be used as alternatives to real measurements with less than 0.3-mm accuracy and very high reliability.