종양형성에서의 Ku단백질의 역할

조병옥,박춘매,장인엽 朝鮮大學校 附設 醫學硏究所 2007 The Medical Journal of Chosun University Vol.32 No.2

Ku is a protein which act as a repairing enzyme for the DNA double strand breaks (DSBs). It has a heterodimeric structure composed of two subunits, Ku70 and Ku86. The detail mechanism of Ku in DNA repair processes is still not unknown, but it is certain that Ku is a one of key protein in maintenance of chromosomal integrity and cell survival. Recent studies reported that dysfunction of Ku protein is related to the development of radioresistance in case of overexpression of Ku and tumorigenesis with Ku underexpression. As Ku may act as either a tumor suppressor or an oncoprotein, precise regulation of Ku function may be important for the tumor suppression. Ku may be used for the treatment of cancer to resist radiotherapy or chemotherapy.

안구적출에 따른 위둔덕의 칼슘결합단백질의 재구축 및 상호 연관성

안병수,고길석,안명수,김경주,권안성,정명섭,박춘매,조병옥,김진우,Samudra Acharya,Parmeshwar Narayan Amatya,장인엽 朝鮮大學校 附設 醫學硏究所 2007 The Medical Journal of Chosun University Vol.32 No.1

Background: Superior colliculus is a part of midbrain, and participates in the visual reflexes, It receives afferent fibers from optic nerve, visual cortex, and spinotectal tract. After optic deprivation, the microscopic structure of the superior colliculus changed. Calcium-binding proteins (CBPs) Play an important role in the neuronal protection, differentiation and reorganization of the central nervous system, Objectives and Methods: The effects of neonatal retinal deafferentation on a CBPs, calbindm D-28k (CB), Parvalbumin (PB) and calretimn (CR), and the existence of colocalization between the CBPs were examined immunohistochemically in the rat superior colliculus. Results: On the experimental (contralateral to enucleation) side of superior colliculus, the number of CB-immunoreactive (IR) cells was reduced (77.4% compared to control), but not fibers. The number of PB-IR neurons and fibers was also reduced on the experimental side (88.5% compared to control), In the other hand, the CR-IR cells were dramatically increased (642% compared to control), but CR-IR fibers were markedly decreased on the experimental side. The colocalization between CB-CR and PV-CR was rarely observed in the superior colliculus Conclusion: These results suggest that the changes of retinotectal projection may alter the expressional pattern of CBPs in different manners; relatively stable in CB- and PV-IR neurons and plastic in CR-IR neurons.

Mechanical Performance, Water Absorption Behavior and Biodegradability of Poly(methyl methacrylate)-Modified Starch/SBR Biocomposites

Mei-Chun Li,Xin Ge,조을룡 한국고분자학회 2013 Macromolecular Research Vol.21 No.7

Natural corn starch was modified by surface grafting with poly(methyl methacrylate) (PMMA) through emulsion copolymerization and then compounded with styrene-butadiene rubber (SBR) latex in order to prepare PMMA-modified starch/SBR biocomposites. The effect of methyl methacrylate (MMA) and starch concentration on the mechanical properties, morphology, toluene swelling behavior, water absorption behavior and biodegradability of PMMA-modified starch/SBR biocomposites was investigated. Results showed that the optimum mechanical properties were achieved when the concentrations of MMA and starch were 10 and 30 phr, respectively, which could be also confirmed through the observations from FE-SEM micrographs and equilibrium welling test. Guth-Gold and Halpin-Tsai models were employed to predict the modulus of PMMA-modified starch/SBR biocomposites. Halpin-Tsai model was better fitted with the experimentally measured data than Guth-Gold model. The water absorption ratio of PMMA-modified starch/SBR biocomposites was strongly influenced by the immersion time and the starch concentration, which further caused a significant effect on the biodegradability of biocomposites.

Sequence Divergence of Recently Duplicate Genes in Soybean (Glycine max L. Merr.)

Chun Mei Cai,Kyu Jung Van,Moon Young Kim,Suk Ha Lee 한국유전학회 2008 Genes & Genomics Vol.30 No.3

Sequence divergence of duplicate genes was investigated in soybean, a diploidized paleopolyploid. To examine gene duplication, a total of seven primers designed from expressed sequence tags (ESTs) were selected for this study because they produced (1) a single band but showed poor sequencing quality and (2) double bands on an agarose gel. After PCR amplification with genomic DNA, duplicate genes were identified by cloning and subsequent sequencing of twenty randomly-selected clones. Based on their alignment, two or three classes were identified in each amplicon. Linkage analysis confirmed that two duplicate loci were located on different chromosomes. The exon/intron structure was conserved between duplicate gene pairs. A detailed examination of the variation between duplicate pairs showed that the coding regions are highly conserved while many substitutions and insertion/deletions (indels) were identified in non-coding regions. In particular, non-homologs fragments were numerous and, on average, 82 bp in length within the non-coding region. Quantitative trait loci (QTL) for some major agronomic characters, such as seed protein and oil, seed yield, plant height, and corn earworm resistance, were positioned across duplicate loci of TC225246 and TC224550, suggesting that the gene families appear to have retained similar functions throughout genome duplication and evolution events.

Let Love Continue Enhancing the Organ Donor Nursing Competency of Intensive Care Unit Nurses

MEI-CHUN, WU,HUNG-FEI, CHIANG,MIN-LAN, CHANG 한국간호과학회 2019 한국간호과학회 학술대회 Vol.2019 No.10

Liriodenine Inhibits Dopamine Biosynthesis and L-DOPA-Induced Dopamine Content in PC12 Cells

Chun Mei Jin,Jae Joon Lee,Yoo Jung Yang,Yu Mi Kim,Young Kyoon Kim,Shi Yong Ryu,이명구 대한약학회 2007 Archives of Pharmacal Research Vol.30 No.8

The inhibitory effects of liriodenine, an aporphine isoquinoline alkaloid, on dopamine biosynthesis and L-DOPA-induced dopamine content increases in PC12 cells were investigated. Treatment of PC12 cells with 5-10 μM liriodenine significantly decreased the intracellular dopamine content in a concentration-dependent manner (IC50 value, 8.4 μM). Liriodenine was not cytotoxic toward PC12 cells at concentrations up to 20 μM. Tyrosine hydroxylase (TH) and aromatic L-amino acid decarboxylase (AADC) activities were inhibited by 10 μM liriodenine to 20-70% and 10-14% of control levels at 3-12 h, respectively; TH activity was more influenced than AADC activity. The levels of TH mRNA, intracellular cyclic AMP and basal Ca2+ concentration were also decreased by 10 μM liriodenine. In addition, 10 μM liriodenine reduced L-DOPA (20-100 μM)-induced increases in dopamine content. However, 10 μM liriodenine resulted in a protective effect against L-DOPA (50-100 μM)-induced cytotoxicity. These results suggest that liriodenine regulates dopamine biosynthesis by partially reducing TH activity and TH gene expression and has protective effects against L-DOPA-induced cytotoxicity in PC12 cells.

Antenatal Depression in East Asia: A Review of the Literature

Mei-Chun Hsiao,Mei-Chun Hsiao,Chia-Yih Liu 대한신경정신의학회 2012 PSYCHIATRY INVESTIGATION Vol.9 No.2

This current study’s goal is to summarize the literature regarding Antenatal Depression (AD) in the East Asian countries of Taiwan, China (including Hong Kong and Macau), Japan, and Korea. The main search utilized a Pub med Chinese Electronic Periodical Service (CEPS) literature review using keywords ‘AD’, and ‘Prenatal Depression’ with searches for ‘Japan’, ‘Korea’, ‘Taiwan’, ‘Hong Kong’ and Macau’. The rates of AD in East Asia appear to be relatively close to those in the Western literature, although certain studies showed slightly decreased rates. Many of the risk factors for AD were the same in the Eastern and Western literature. These risk factors included demographic factors such as younger age, smoking, low education and income, and unemployment. Other risk factors were physical symptoms such as menstrual pains and nausea. Finally, psychological factors such as a poor response to the pregnancy, poor spousal support, and poor family support were associated with AD. With regard to treatment, there were no studies examining the administration of psychotropic medications for AD. The literature from East Asia both confirmed many Western findings and made unique contributions to the literature on AD. The treatment of AD in East Asia appears to be an entity which, despite its morbidity, has not been adequately studied.

Antioxidant Peptide Purified from Enzymatic Hydrolysates of Isochrysis Zhanjiangensis and Its Protective Effect against Ethanol Induced Oxidative Stress of HepG2 Cells

Mei-Fang Chen,Yuan Yuan Zhang,Mei Di He,Cheng Yong Li,Chun Xia Zhou,Peng Zhi Hong,Zhong-Ji Qian 한국생물공학회 2019 Biotechnology and Bioprocess Engineering Vol.24 No.2

Marine microalgae have been widely applied in cosmaceuticals, nutraceuticals, and functional foods. In the present study, we first investigated the hepatoprotective effects of peptide purified from microalgae, Isochrysis zhanjiangensis on HepG2 cells alcoholic injury. I. zhanjiangensis was hydrolyzed utilizing chymotrypsin, trypsin, pepsin, and by vitro gastrointestinal digestion. Among hydrolysates, the gastrointestinal hydrolysate showed relatively high free radical scavenging ability preliminarily and was purified with following sequential chromatography methods. The amino acid sequence and molecular mass of the purified peptide from I. zhanjiangensis (PIZ) was identified as Asn-Asp-Ala-Glu-Tyr-Gly-Ile-Cys-Gly-Phe (NDAEYGICGF; MW, 1088.16 Da) via Q-TOF ESI/MS. Additionally, PIZ attenuated ethanol-induced cytotoxicity and inhibited the production of intracellular reactive oxygen species by DCFH-DA assay. Western blot results showed that superoxide dismutase (SOD) and glutathione (GSH) levels up-regulated with PIZ treatment before alcohol exposure while gamma-glutamyltransferase (GGT) protein expression down-regulated. These results provide an opportunity to discover new highly active peptide against alcohol toxicity in HepG2 cells.

An Exploration of Nurses' Knowledge and Clinical Practice on Pressure Ulcer Prevention and Management in a Medical Center of Southern Taiwan

Mei-Chun Chen,Hsiu-Yuan Lo 한국간호과학회 2005 한국간호과학회 학술대회 Vol.2005 No.10

Optimization of SNP Genotyping Assay with Fluorescence Polarization Detection

Chun Mei Cai,반규정,김문영,이석하 한국작물학회 2005 Korean journal of crop science Vol.50 No.6

Single nucleotide polymorphisms (SNPs) are valuable DNA markers due to their abundance and potential for use in automated high-throughput genotyping. Numerous SNP genotyping assays have been developed. In this report, one of effective and high throughput SNP genotyping assays which was named the template-directed dye-terminator incorporation with fluorescence polarization detection (FP-TDI) was described. Although the most of this assay succeed, the objective of this work was to determine the reasons for the failures, find ways to improve the assay and reduce the running cost. Ninety F2-derived soybean, Glycine max (L.) Merr., RILs from a cross between Pureunkong and Jinpumkong 2 were genotyped at four SNPs. FP measurement was done on Victor3 microplate reader (Perkinelmer Inc., Boston, MA, USA). Increasing the number of thermal cycles in the single-base extension step increased the separation of the FP values between the products corresponding to different genotypes. But in some assays, excess of heterozygous genotypes was observed with increase of PCR cycles. We discovered that the excess heterozygous was due to misincorporation of one of the dye-terminators during the primer extension reaction. After pyrophosphatase incubation and thermal cycle control, misincoporation can be effectively prevented. Using long amplicons instead of short amplicons for SNP genotyping and decreasing the amount of dye terminator and Acyclopol Taq polymerase to 1/2 or 1/3 decreased the cost of the assay. With these minor adjustments, the FP-TDI assay can be used more accurately and cost-effectively.