PHF2 histone demethylase acts as a tumor suppressor in association with p53 in cancer

Lee, K-H,Park, J-W,Sung, H-S,Choi, Y-J,Kim, W H,Lee, H S,Chung, H-J,Shin, H-W,Cho, C-H,Kim, T-Y,Li, S-H,Youn, H-D,Kim, S J,Chun, Y-S Macmillan Publishers Limited 2015 Oncogene Vol.34 No.22

Plant homeodomain finger 2 (PHF2) has a role in epigenetic regulation of gene expression by demethylating H3K9-Me2. Several genome-wide studies have demonstrated that the chromosomal region including the PHF2 gene is often deleted in some cancers including colorectal cancer, and this finding encouraged us to investigate the tumor suppressive role of PHF2. As p53 is a critical tumor suppressor in colon cancer, we tested the possibility that PHF2 is an epigenetic regulator of p53. PHF2 was associated with p53, and thereby, promoted p53-driven gene expression in cancer cells under genotoxic stress. PHF2 converted the chromatin that is favorable for transcription by demethylating the repressive H3K9-Me2 mark. In an HCT116 xenograft model, PHF2 was found to be required for the anticancer effects of oxaliplatin and doxorubicin. In PHF2-deficient xenografts, p53 expression was profoundly induced by both drugs, but its downstream product p21 was not, suggesting that p53 cannot be activated in the absence of PHF2. To find clinical evidence about the role of PHF2, we analyzed the expressions of PHF2, p53 and p21 in human colon cancer tissues and adjacent normal tissues from patients. PHF2 was downregulated in cancer tissues and PHF2 correlated with p21 in cancers expressing functional p53. Colon and stomach cancer tissue arrays showed a positive correlation between PHF2 and p21 expressions. Informatics analyses using the Oncomine database also supported our notion that PHF2 is downregulated in colon and stomach cancers. On the basis of these findings, we propose that PHF2 acts as a tumor suppressor in association with p53 in cancer development and ensures p53-mediated cell death in response to chemotherapy.

Biochemical, pharmaceutical and therapeutic properties of long-acting lithocholic acid derivatized exendin-4 analogs

Chae, S.Y.,Jin, C.H.,Shin, J.H.,Son, S.,Kim, T.H.,Lee, S.,Youn, Y.S.,Byun, Y.,Lee, M.S.,Lee, K.C. Elsevier Science Publishers 2010 Journal of controlled release Vol.142 No.2

Alterations in the physicochemical characteristics of peptide drugs can transform their biological and pharmaceutical features. In the present study, we explored the potentials of lithocholic acid (LCA)-modified exendin-4 derivatives as novel long-acting GLP-1 receptor agonists. Exendin-4 was modified with lithocholic acid at two lysine residues to produce three derivatives that were obtained by reverse-phase HPLC separation, namely, Lys<SUP>12</SUP>-LCA-exendin-4 (LCA-M2), Lys<SUP>27</SUP>-LCA-exendin-4 (LCA-M1), and Lys<SUP>12,27</SUP>-LCA-exendin-4 (LCA-Di)). The biological, pharmacological, and physicochemical characteristics of these three exendin-4 analogues were then investigated. Although slight reductions in the GLP-1 receptor binding capacity and insulinotropic activity of exendin-4 were observed after derivatization, the mono-LCA substitutions, especially LCA-M1, well-preserved antidiabetic activity in type 2 diabetic mice when administered subcutaneously or intraperitoneally. Furthermore, the pharmacokinetic characteristics were dramatically enhanced, that is, absorption was delayed and elimination half-life was increased (1.6+/-0.4 and 9.7+/-1.4h by exendin-4 and LCA-M1, respectively). The enhanced long-acting characteristics of the derivative was found to be due to albumin binding and nanoparticle formation, and these were verified by the restoration of normoglycemia in type 2 diabetic mice after single injection (>24h, >10nmol/kg, s.c.) and daily injections (15nmol/kg/day) maintained normoglycemia for the 4-week administration period. Furthermore, antidiabetic potentials, such as, glucose clearance kinetics and percentage areas occupied by pancreatic β-cells were also enhanced by long-term LCA-M1 administration. The present study demonstrates that the derivatization of exendin-4 with LCA offers a possible means of producing a long-acting GLP-1 receptor agonist.

Electrochemical analysis on the growth of oxide formed on stainless steels in molten carbonate at 650 ^oC

Ahn, S.,Oh, K.,Kim, M.,Youn, J.,Jo, K.,Kim, K.,Kwon, H. Pergamon Press ; Elsevier Science Ltd 2014 International journal of hydrogen energy Vol.39 No.23

The oxide growth on stainless steel (SS) 310S and 316L, used as a cathode current collector material of molten carbonate fuel cell (MCFC), were examined in the mixture of 62 mol% Li<SUB>2</SUB>CO<SUB>3</SUB>-38 mol% K<SUB>2</SUB>CO<SUB>3</SUB> at 650 <SUP>o</SUP>C by measuring the change in corrosion potential and potentiodynamic response of the alloys and also in terms of impedance analysis on the alloy|oxide layer|electrolyte system. The corrosion potential of SS 316L was in an active region for 12 h-immersion, whereas that of SS 310S drastically increased after 6 h-immersion due to an active to passive transition. The corrosion rate of the two SSs decreased with immersion due to the growth of protective oxide. However, the decrease in the corrosion rate of SS 310S is much greater than that of SS 316L. The oxide formed on the two SSs was found to be duplex layer, composed of inner Cr enriched oxide and outer Fe enriched oxide. However, the inner Cr enriched layer of 310S is more clearly separated from the outer Fe enriched layer than that of SS 316L due primarily to the higher Cr content in SS 310S. The drastic increase in the corrosion potential of SS 310S after 6 h-immersion is closely associated with the growth of the inner Cr enriched oxide layer. The corrosion resistance of SS depends dominantly on the resistance of the inner Cr enriched oxide that is determined form the impedance analysis on the alloy|oxide layer|electrolyte system. The higher corrosion resistance of SS 310S compared with SS 316L results from the more protective inner Cr enriched oxide layer, as confirmed by its higher resistance associated with the higher Cr content in SS 310S.

Inhalable self-assembled albumin nanoparticles for treating drug-resistant lung cancer

Choi, S.H.,Byeon, H.J.,Choi, J.S.,Thao, L.,Kim, I.,Lee, E.S.,Shin, B.S.,Lee, K.C.,Youn, Y.S. Elsevier Science Publishers 2015 Journal of controlled release Vol.197 No.-

Direct pulmonary delivery of anti-cancer agents is viewed as an effective way of treating lung cancer. Here, we fabricated inhalable nanoparticles made of human serum albumin (HSA) conjugated with doxorubicin and octyl aldehyde and adsorbed with apoptotic TRAIL protein (TRAIL/Dox HSA-NP). The octyl aldehyde and doxorubicin endowed HSA with significant hydrophobicity that facilitated self-assembly. TRAIL/Dox HSA-NP was found to have excellent particle size (~340nm), morphology, dispersability, and aerosolization properties. TRAIL/Dox HSA-NP displayed synergistic cytotoxicity and apoptotic activity in H226 lung cancer cells vs. HSA-NP containing TRAIL or Dox alone. TRAIL/Dox HSA-NP was well deposited in the mouse lungs using an aerosolizer, and TRAIL and Dox-HSA were found to be gradually released over 3days. The anti-tumor efficacy of pulmonary administered TRAIL/Dox HSA-NP was evaluated in BALB/c nu/nu mice bearing H226 cell-induced metastatic tumors. It was found that the tumors of H226-implanted mice treated with TRAIL/Dox HSA-NP were remarkably smaller and lighter than those of mice treated with TRAIL or Dox HSA-NP alone (337.5+/-7.5; 678.2+/-51.5; and 598.9+/-24.8mg, respectively). Importantly, this improved anti-tumor efficacy was found to be due to the synergistic apoptotic effects of Dox and TRAIL. In the authors' opinion, TRAIL/Dox HSA-NP offers a potential inhalable anti-lung cancer drug delivery system. Furthermore, the synergism displayed by combined use of Dox and TRAIL could be used to markedly reduce doxorubicin doses and minimize its side effects.

Micropropagation of Superior Variety of Japanese Pepper Tree (Zanthoxylum piperitum Dc.)

Son, S. H 한국식물조직배양학회 1995 식물생명공학회지 Vol.22 No.3

Live attenuated nephropathogenic infectious bronchitis virus vaccine provides broad cross protection against new variant strains.

Lim, T-H,Kim, M-S,Jang, J-H,Lee, D-H,Park, J-K,Youn, H-N,Lee, J-B,Park, S-Y,Choi, I-S,Song, C-S Poultry Science Association, etc 2012 Poultry science Vol.91 No.1

<P>Infectious bronchitis virus (IBV) infections cause great economic losses to the poultry industry worldwide, and the emergence of new variant strains complicates disease control. The present study investigated the genetic and protectotypic features of newly emerged Korean IBV strains. A phylogenetic analysis showed that several recent isolates formed 2 different clusters (new cluster 1 and 2), which were distinct from other preexisting clusters. New cluster 1 IBV strains represented recombinants between Korean nephropathogenic strain KM91 and the QXIBV strain. New cluster 2 IBV strains showed low amino acid homology (<58.7%) compared with previous isolates. We evaluated the protective efficacy of commercial IBV vaccines (H120 and K2 strain) against these new isolates. In cross-protection studies, the H120 strain did not provide sufficient protection against these variants. However, highly attenuated nephropathogenic IBV vaccine, K2 strain, provided significantly higher levels of protection against variants compared with chickens vaccinated with H120 (P < 0.05 or better). These results indicate that the K2 vaccine could be helpful for the reduction of economic losses caused by newly evolving IBV recombinants (new cluster 1) and variants (new cluster 2).</P>

An emerging recombinant cluster of nephropathogenic strains of avian infectious bronchitis virus in Korea

Lim, T.H.,Lee, H.J.,Lee, D.H.,Lee, Y.N.,Park, J.K.,Youn, H.N.,Kim, M.S.,Lee, J.B.,Park, S.Y.,Choi, I.S.,Song, C.S. Elsevier Science 2011 Infection, genetics and evolution Vol.11 No.3

The infectious bronchitis virus (IBV) is continuously evolving through point mutation and recombination of their genome, subsequently the emergence of IBV variants complicates disease control. The objective of this study was to investigate genetic characterization of new IBV variants isolated from commercial chicken flocks in Korea collected between 2005 and 2010. Phylogenetic analysis revealed that all new IBV isolates belonged to Korean group II (K-II), which included the nephropathogenic IBV strains. However, the isolates formed a new gene cluster that was distinguished from the two distinct K-II subgroups (KM91-like and QX-like). Recombination events were identified in the S1 gene, with their putative parental strains being the KM91-like or QX-like subgroup. In addition, two crossover sites were observed in the S1 gene of IBV isolates. These results suggest that natural genetic recombination between heterologous strains classified into different genetic groups has occurred and may have caused the emergence of new IBV strains. This finding provides important information on IBV evolution and is essential for the effective control of IB in Korea.

문학반응이론에 의한 보건의학기술계열 국가시험개선방안에 관한 연구

이창규,이승관,조경진,박종성,정수경,유병서,박상숙,윤효숙,황선철,문경환,김정민,함용운,김지환,임국환,김영순,윤경희,황성준 高麗大學校 倂設 保健大學 保健科學硏究所 1998 保健科學論集 Vol.24 No.1

The nationally-governed examinations for certification of allied health professions in Korea have been continued for thirty three years. During that time, there were a lot of managerial improvements in carrying out the examinations, for example, the looking-over the papers converted from manual method to computerized one. Nevertheless, the overall aspects of item management in the national examinations are still remained as obsolete style. In some developed countries they have already tried or adopted computerized system in making questions, executing item analysis, developing item banking, and in overall management of examinations, looking over papers for their national licensure examinations, and have established good reputations. Since the National Health Personnel Licensing Examination Board was established in 1998, now we can expect there would be a lots of improvements in the managerial systems and organizational structures associated with the national licensing examinations suggesting followings. 1. The contents and scope of the licensing examinations based on job analysis should be announced publicaly. 2. Items should be developed based on the scopes and contents of job characteristics. 3. All the developed items for the licensing examinations should be tested quantitatively prior to banking items. 4. All the parameters of the stored items should be fully estimated through item response theory. 5. All the efforts should be given in order to execute the examinations in individual residential areas on behalf of every examinee. 6. To the licensing examination system the Computerized Adaptive Testing system should be introduced in order to enhance the efficiencies. 7. Security enhancement on the stored items should be reminded in order to prevent leaking out the banking items. 8. Much more improvements should be made for the proper job evaluations. 9. Every efforts should be given to prevent cheatings encountable during the examinations. 10. Make the best of professional volunteers from the various fields in the execution of licensing examinations. 11. Consider a new system in that examinations can be executed twice or more in a year. 12. The current methods of presiding over the examinations should be replaced by a more reasonable one. 13. The results of the examinations should be announced as soon as possible in order not to prolong the examinees' unemployment periods. 14. The National Health Personnel Licensing Examination Board should try to rationalize the management keeping step with the information-oriented society.

Butyric acid production from softwood hydrolysate by acetate-consuming Clostridium sp. S1 with high butyric acid yield and selectivity

Kim, M.,Kim, K.Y.,Lee, K.M.,Youn, S.H.,Lee, S.M.,Woo, H.M.,Oh, M.K.,Um, Y. Elsevier Applied Science 2016 Bioresource technology Vol.218 No.-

The aim of this work was to study the butyric acid production from softwood hydrolysate by acetate-consuming Clostridium sp. S1. Results showed that Clostridium sp. S1 produced butyric acid by simultaneously utilizing glucose and mannose in softwood hydrolysate and, more remarkably, it consumed acetic acid in hydrolysate. Clostridium sp. S1 utilized each of glucose, mannose, and xylose as well as mixed sugars simultaneously with partially repressed xylose utilization. When softwood (Japanese larch) hydrolysate containing glucose and mannose as the main sugars was used, Clostridium sp. S1 produced 21.17g/L butyric acid with the yield of 0.47g/g sugar and the selectivity of 1 (g butyric acid/g total acids) owing to the consumption of acetic acid in hydrolysate. The results demonstrate potential of Clostridium sp. S1 to produce butyric acid selectively and effectively from hydrolysate not only by utilizing mixed sugars simultaneously but also by converting acetic acid to butyric acid.

Molecular Analysis Oculocutaneous Albinism Patients in Korea

Hwang, J. H Korean Dermatological Association 1997 Annals of Dermatology Vol.9 No.3