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Angiopoietin-1 and -2 and vascular endothelial growth factor expression in ovarian grafts after cryopreservation using two methods

  • Cho, In Ae;Lee, Yeon Jee;Lee, Hee Jung;Choi, In Young;Shin, Jeong Kyu;Lee, Soon Ae;Lee, Jong Hak;Choi, Won Jun
    • Clinical and Experimental Reproductive Medicine
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    • v.45 no.3
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    • pp.143-148
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    • 2018
  • Objective: The favored method of preserving fertility in young female cancer survivors is cryopreservation and autotransplantation of ovarian tissue. Reducing hypoxia until angiogenesis takes place is essential for the survival of transplanted ovarian tissue. The aim of this study was to investigate the role of angiopoietin-1 (Angpt-1), angiopoietin-2 (Angpt-2), and vascular endothelial growth factor (VEGF) in ovarian tissue grafts that were cryopreserved using two methods. Methods: Ovarian tissues harvested from ICR mice were divided into three groups: group I (control), no cryopreservation; group II, vitrification in EFS (ethylene-glycol, ficoll, and sucrose solution)-40; and group III, slow freezing in dimethyl sulfoxide. We extracted mRNA for VEGF, Angpt-1, and Angpt-2 from ovarian tissue 1 week following cryopreservation and again 2 weeks after autotransplantation. We used reverse transcriptase-polymerase chain reaction to quantify the levels of VEGF, Angpt-1, and Angpt-2 in the tissue. Results: Angpt-1 and Angpt-2 expression decreased after cryopreservation in groups II and III. After autotransplantation, Angpt-1 and Angpt-2 expression in ovarian tissue showed different trends. Angpt-1 expression in groups II and III was lower than in group I, but Angpt-2 in groups II and III showed no significant difference from group I. The vitrified ovarian tissues had higher expression of VEGF and Angpt-2 than the slow-frozen ovarian tissues, but the difference was not statistically significant. Conclusion: Our results indicate that Angpt-2 may play an important role in ovarian tissue transplantation after cryopreservation although further studies are needed to understand its exact function.

Identification of cis-Regulatory Region Controlling Semaphorin-1a Expression in the Drosophila Embryonic Nervous System

  • Hong, Young Gi;Kang, Bongsu;Lee, Seongsoo;Lee, Youngseok;Ju, Bong-Gun;Jeong, Sangyun
    • Molecules and Cells
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    • v.43 no.3
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    • pp.228-235
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    • 2020
  • The Drosophila transmembrane semaphorin Sema-1a mediates forward and reverse signaling that plays an essential role in motor and central nervous system (CNS) axon pathfinding during embryonic neural development. Previous immunohistochemical analysis revealed that Sema-1a is expressed on most commissural and longitudinal axons in the CNS and five motor nerve branches in the peripheral nervous system (PNS). However, Sema-1a-mediated axon guidance function contributes significantly to both intersegmental nerve b (ISNb) and segmental nerve a (SNa), and slightly to ISNd and SNc, but not to ISN motor axon pathfinding. Here, we uncover three cis-regulatory elements (CREs), R34A03, R32H10, and R33F06, that robustly drove reporter expression in a large subset of neurons in the CNS. In the transgenic lines R34A03 and R32H10 reporter expression was consistently observed on both ISNb and SNa nerve branches, whereas in the line R33F06 reporter expression was irregularly detected on ISNb or SNa nerve branches in small subsets of abdominal hemisegments. Through complementation test with a Sema-1a loss-of-function allele, we found that neuronal expression of Sema-1a driven by each of R34A03 and R32H10 restores robustly the CNS and PNS motor axon guidance defects observed in Sema-1a homozygous mutants. However, when wild-type Sema-1a is expressed by R33F06 in Sema-1a mutants, the Sema-1a PNS axon guidance phenotypes are partially rescued while the Sema-1a CNS axon guidance defects are completely rescued. These results suggest that in a redundant manner, the CREs, R34A03, R32H10, and R33F06 govern the Sema-1a expression required for the axon guidance function of Sema-1a during embryonic neural development.

A study on the variations of water temperature and sonar performance using the empirical orthogonal function scheme in the East Sea of Korea (동해에서 경험직교함수 기법을 이용한 수온과 소나성능 변화 연구)

  • Young-Nam Na;Changbong Cho;Su-Uk Son;Jooyoung Hahn
    • The Journal of the Acoustical Society of Korea
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    • v.43 no.1
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    • pp.1-8
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    • 2024
  • For measuring the performance of passive sonars, we usually consider the maximum Detection Range (DR) under the environment and system parameters in operation. In shallow water, where sound waves inevitably interacts with sea surface or bottom, detection generally maintains up to the maximum range. In deep water, however, sound waves may not interact with sea surface or/and bottom, and thus there may exist shadow zones where sound waves can hardly reach. In this situation, DR alone may not completely define the performance of each sonar. For complete description of sonar performance, we employ the concept 'Robustness Of Detection (ROD)'. In the coastal region of the East Sea, the spatial variations of water masses have close relations with DR and ROD, where the two parameters show reverse spatial variations in general. The spatial and temporal analysis of the temperature by employing the Empirical Orthogonal Function (EOF) shows that the 1-st mode represents typical pattern of seasonal variation and the 2-nd mode represents strength variations of mixed layers and currents. The two modes are estimated to explain about 92 % of the variations. Assuming two types of targets located at the depths of 5 m (shallow) and 100 m (deep), the passive sonar performance (DR) gives high negative correlations (about -0.9) with the first two modes. Most of temporal variations of temperature occur from the surface up to 200 m in the water column so that when we assume a target at 100 m, we can expect detection performance of little seasonal variations with passive sonars below 100 m.

Transiently Experessed Salt-Stress Protection of Rice by Transfer of a Bacterial Gene, mtlD

  • Lee, Eun-A;Kim, Jung-Dae;Cha, Yoo-Kyung;Woo, Dong-Ho;Han, In-Seob
    • Journal of Microbiology and Biotechnology
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    • v.10 no.3
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    • pp.415-418
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    • 2000
  • Productivity of a rice plant is greatly influenced by salt stress. One of the ways to achieve tolerance to salinity is to transfer genes encoding protective enzymes from other organisms, such as microorganisms. The bacterial gene, mtlD, which encodes mannitol-1-phosphate dehydrogenase (Mtl-DH), was introduced to the cytosol of a rice plant by an imbibition technique to overproduce mannitol. The germination and survival rate of the imbibed rice seeds were markedly increased by transferring the mtlD gene when it was delivered in either a pBIN19 or pBmin binary vector. When a polymerase chain reaction was performed with the genomic DNAs of the imbibed rice leaves as a template and with mtlD-specific primers, several lines were shown to contain an exogenous mtlD DNA. However, a reverse transcription (RT)-PCR analysis revealed that not all of them showed an expression of this foreign gene. This paper demonstrates that the growth and germination of rice plants transiently transformed with the bacterial gene, mtlD, are enhanced and these enhancements may have resulted from the experssion of the mtlD gene. The imbibition method empolyed in this study fulfills the requirements for testing the function of such a putative gene in vivo prior to the production of a stable transgenic plant.

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The Histone Demethylase PHF2 Promotes Fat Cell Differentiation as an Epigenetic Activator of Both C/EBPα and C/EBPδ

  • Lee, Kyoung-Hwa;Ju, Uk-Il;Song, Jung-Yup;Chun, Yang-Sook
    • Molecules and Cells
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    • v.37 no.10
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    • pp.734-741
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    • 2014
  • Histone modifications on major transcription factor target genes are one of the major regulatory mechanisms controlling adipogenesis. Plant homeodomain finger 2 (PHF2) is a Jumonji domain-containing protein and is known to demethylate the histone H3K9, a repressive gene marker. To better understand the function of PHF2 in adipocyte differentiation, we constructed stable PHF2 knock-down cells by using the mouse pre-adipocyte cell line 3T3-L1. When induced with adipogenic media, PHF2 knock-down cells showed reduced lipid accumulation compared to control cells. Differential expression using a cDNA microarray revealed significant reduction of metabolic pathway genes in the PHF2 knock-down cell line after differentiation. The reduced expression of major transcription factors and adipokines was confirmed with reverse transcription- quantitative polymerase chain reaction and Western blotting. We further performed co-immunoprecipitation analysis of PHF2 with four major adipogenic transcription factors, and we found that CCATT/enhancer binding protein (C/EBP)${\alpha}$ and C/EBP${\delta}$ physically interact with PHF2. In addition, PHF2 binding to target gene promoters was confirmed with a chromatin immunoprecipitation experiment. Finally, histone H3K9 methylation markers on the PHF2-binding sequences were increased in PHF2 knock-down cells after differentiation. Together, these results demonstrate that PHF2 histone demethylase controls adipogenic gene expression during differentiation.

Diagnostic and Prognostic Value of miR-205 in Colorectal Cancer

  • Orang, Ayla Valinezhad;Safaralizadeh, Reza;Feizi, Mohammad Ali Hosseinpour;Somi, Mohammad Hossein
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.9
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    • pp.4033-4037
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    • 2014
  • Emerging evidence has shown associations of microRNA-205 (miR-205) with crucial cell processes such as the epithelial-mesenchymal transition (EMT) and aberrant expression with tumorigenesis in many types of human malignancy. This prospective study characterized the contribution of miR-205 to the colorectal cancer (CRC) tumorigenesis. The real-time reverse transcription-polymerase chain reaction was used to examine miR-205 levels prospectively in 36 pairs of samples of CRC tissue and adjacent noncancerous tissue (>2 cm from cancer tissue). In addition, the relationship between miR-205 levels and clinicopathological features was explored. The capability of miR-205 to function as a tumor marker was also examined. miR-205 expression levels did not show significant changes overall. However, miR-205 was significantly downregulated in a group of CRC samples compared with matched noncancerous tissue samples. Moreover, decreased miR-205 correlated significantly with lymphatic metastasis. A receiver operating characteristic (ROC) curve also showed an optimum cut off point of $1.4{\times}10^{-3}$ to distinguish lymphatic metastatic CRCs from non-metastatic CRCs. Interestingly we found lymphatic metastasis in almost 80% of the depressed samples. This study suggested that miR-205 could be reduced in the majority of metastatic CRCs and the risk of CRC metastasis may be predicted by monitoring miR-205 in patient samples collected at the time of the initial diagnosis. Therefore, targeting miR-205 and its potential environmental activators might be a promising therapeutic option to prevent malignant progression toward metastasis.

Analysis of AIGaAs/GaAs Depleted Optical Thyristor using bottom mirror (하부 거울층을 이용한 AIGaAs/GaAs 완전 공핍 광 싸이리스터 특성 분석)

  • Choi Woon-Kyiug;Kim Doo-Gun;Choi Young-Wan
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.42 no.1
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    • pp.39-46
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    • 2005
  • We fabricate and analyze fully depleted optical thyristors (DOTs) using quarter wavelength reflector stacks (QWRS). QWRS are employed as bottom mirrors to enhance the emission efficiency as well as the optical sensitivity. In order to analyze their switching characteristics, S-shape nonlinear current-voltage curves are simulated and the reverse full-depletion voltages (Vneg's) of DOTs are obtained as function of semiconductor parameters by using a finite difference method (FDM). The fabricated DOTs show sufficient nonlinear s-shape I-V characteristics and switching voltage changes of these devices with and without bottom mirrors show 1.82 V and 1.52 V, respectively. Compared to a conventional DOT, this device with the bottom mirrors shows about 20% and 46% enhancement in switching voltage change and spontaneous emission efficiency, respectively.

Correction of Minor-Form and Microform Cleft Lip Using Modified Muscle Overlapping with a Minimal Skin Incision

  • Kim, Min Chul;Choi, Dong Hun;Bae, Sung Gun;Cho, Byung Chae
    • Archives of Plastic Surgery
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    • v.44 no.3
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    • pp.210-216
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    • 2017
  • Background In treating minor-form or microform cleft lip, obtaining an optimal result is a challenge because of the visible scarring caused by traditional surgery. We present a refined method using muscle overlapping with a minimal skin incision in patients younger than 3 years, a group characterized by thin muscle. Methods The surgical technique involves restoration of the notched vermillion using Z-plasty, formation of the philtral column using overlapping of an orbicularis oris muscle flap through an intraoral incision, and correction of the cleft lip nasal deformity using a reverse-U incision and V-Y plasty. A single radiologist evaluated ultrasonographic images of the upper lip. Results Sixty patients were treated between September 2008 and June 2014. The age at the time of operation ranged from 6 to 36 months (mean, 26 months). The follow-up period ranged from 8 to 38 months (mean, 20 months) in minor-form cases and from 14 to 64 months (mean, 37 months) in microform cases. A notched cupid's bow was corrected in 10 minor-form cases and 50 microform cases. Ultrasonographic images were obtained from 3 patients with minor-form cleft lip and 9 patients with microform cleft lip 12 months after surgery. The average muscle thickness was 4.5 mm on the affected side and 4.1 mm on the unaffected side. Conclusions The advantages of the proposed procedure include the creation of an anatomically natural philtrum with minimal scarring. This method also preserves the continuity and function of the muscle and provides sufficient augmentation of the philtral column and nostril sill.

Comparison of cytokine expression profiles in infants with a rhinovirus induced lower respiratory tract infection with or without wheezing: a comparison with respiratory syncytial virus

  • Roh, Da Eun;Park, Sook-Hyun;Choi, Hee Joung;Kim, Yeo Hyang
    • Clinical and Experimental Pediatrics
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    • v.60 no.9
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    • pp.296-301
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    • 2017
  • Purpose: The aim of this study was to evaluate whether infants with rhinovirus (RV) infection-induced wheezing and those with respiratory syncytial virus (RSV) infection-induced wheezing have different cytokine profiles in the acute stage. Methods: Of the infants with lower respiratory tract infection (LRTI) between September 2011 and May 2012, 88 were confirmed using reverse transcription polymerase chain reaction and hospitalized. Systemic interferon-gamma ($IFN-{\gamma}$), interleukin (IL)-2, IL-12, IL-4, IL-5, IL-13, and Treg-type cytokine (IL-10) responses were examined with multiplex assay using acute phase serum samples. Results: Of the 88 patients, 38 had an RV infection (RV group) and 50 had an RSV infection (RSV group). In the RV group, the $IFN-{\gamma}$ and IL-10 concentrations were higher in the patients with than in the patients without wheezing (P=0.022 and P=0.007, respectively). In the RSV group, the differences in $IFN-{\gamma}$ and IL-10 concentrations did not reach statistical significance between the patients with and the patients without wheezing (P=0.105 and P=0.965, respectively). The $IFN-{\gamma}$ and IL-10 concentrations were not significantly different between the RV group with wheezing and the RSV group with wheezing (P=0.155 and P=0.801, respectively), in contrast to the significant difference between the RV group without wheezing and the RSV group without wheezing (P=0.019 and P=0.035, respectively). Conclusion: In comparison with RSV-induced LRTI, RV-induced LRTI combined with wheezing showed similar $IFN-{\gamma}$ and IL-10 levels, which may have an important regulatory function.

Generation of Simulated Image from Atmospheric Corrected Landsat TM Images (대기보정된 Landsat TM 영상으로부터 모의영상 제작)

  • Lee, Soo Bong;La, Phu Hien;Eo, Yang Dam;Pyeon, Mu Wook
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.33 no.1
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    • pp.1-9
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    • 2015
  • A remote sensed image simulation following to weather and season conditions can be performed by a reverse atmospheric correction which is a function of image preprocessing. In this study, we have made an experiment to generate the simulated image to the raw image, which is prior to the atmospheric corrected images under the specific weather conditions. The applied methods in this study were the Forster algorithm (1984) and 6S RTM (Radiative Transfer Model). The simulated images has been compared with the original image to analyze compliances. In fact, the results from 6S RTM method show better compliances than Forster, with a mean of RMSE of DN difference 9.35 and a mean of $R^2$ 0.7. In conclusion, a simulated image has practical feasibility when similar to the period and season as the reference image.