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The current statistic data on the open access (OA) journals and institutional repositories show some successes and increased awareness on OA in Asian countries. There are several concerns, however, in regards to the access and use of articles by researchers together with the continued increase of libraries' expenditure for journals. In the present article we introduce five solutions in the global and local perspectives. OA2020 initiative is a global initiative to transform existing journals to OA. Although the practical process of OA2020 remains a challenge, the transformation will increase OA without significant increase of journals and budgets for publishing. The promotion of the local and Asian journals is the second big challenge. Because these local or Asian journals still have important roles in the local research community, they should keep current publishing model of OA at the low cost but with high quality and the better access. The restructuring of the current library budget is the third challenge. The budget for periodicals should be reduced and the saved budget can be used to pay articles processing charge for OA and for purchasing monographs. The fourth important issue is 'the digital blind spot at the young unemployed and retired elderly'. These groups of poorly supported and potentially important researchers have to be considered as a priority issue to the policies on OA and scholarly knowledge. Lastly, we believe there should be different needs for other activities: optimization of the searchable database, governmental policy on open science and international cooperation on OA. ; This work is a product of collaboration and discussion among many scientists, editors of journals, copy editors, librarians, information scientists, and policy makers. Only a small number of participants are included to authors but there are many others contributed. Authors acknowledge their contribution in many different ways ; OAIID:RECH_ACHV_DSTSH_NO:T201713502 ; RECH_ACHV_FG:RR00200001 ; ADJUST_YN: ; EMP_ID:A002236 ; CITE_RATE:0 ; FILENAME:se-4-2-58 FINAL.pdf ; DEPT_NM:의학과 ; EMAIL:jwseo@snu.ac.kr ; SCOPUS_YN:N ; FILEURL:https://srnd.snu.ac.kr/eXrepEIR/fws/file/0bcf2055-985d-4c2b-8a14-1767373cbe38/link ; CONFIRM:Y

Calcium hydroxide is a widely used endodontic medicament for eliminating viable bacteria and inactivating virulence factors. Enterococcus faecalis, a pathogenic gram-positive bacterium, has been associated with refractory apical periodontitis. Because lipoteichoic acid (LTA) is a major virulence factor of gram-positive bacteria, we examined whether calcium hydroxide could detoxify LTA from E. faecalis. An enzyme-linked immunosorbent assay showed that calcium hydroxide–killed E. faecalis was less potent than heat-killed bacteria in stimulating the release of tumor necrosis factor–α by a murine macrophage line, RAW 264.7 (P < 0.05). Pretreatment of LTA with calcium hydroxide remarkably abrogated the ability of LTA to induce the release of tumor necrosis factor–α (P < 0.05). Furthermore, calcium hydroxide–treated LTA was not able to stimulate Toll-like receptor 2, which recognizes functionally intact LTA. These results suggest that calcium hydroxide could detoxify LTA, resulting in attenuation of the inflammatory responses to E. faecalis and its LTA. ; This work was supported by the Korea Research Foundation Grant funded by the Korean Government (MOEHRD) (KRF-2007-314-E00186) and by a grant (03-2007-0090) from the Seoul National University Dental Hospital Research Fund, Republic of Korea.

Introduction: Lipoteichoic acid (LTA) is a major virulence factor of Enterococcus faecal is that is closely associated with refractory apical periodontitis. Recently, we have shown that calcium hydroxide, a commonly used intracanal medicament, abrogated the ability of LTA to stimulate the production of tumor necrosis factor alpha in a murine macrophage line, RAW 264.7. Because calcium hydroxide could potentially modify the glycolipid moiety of LTA, we examined if calcium hydroxide inactivates LTA through deacylation of the LTA. Methods: LTA was prepared from E. faecalis by organic solvent extraction followed by chromatography with the hydrophobic-interaction column and the ion-exchange column. RAW 264.7 cells were stimulated with intact LTA or calcium hydroxide treated LTA for 24 hours, and the productions of nitric oxide (NO) and chemokines interferon-gamma induced protein (IP-10) and macrophage inflammatory protein-1 alpha (MIP-1 alpha) were determined. The glycolipid structure of LTA was analyzed using matrix-assisted laser desorption ionization-time of flight mass spectrometry and thin layer chromatography (TLC). Results: The production of NO, IP-1, and MIP-1 alpha was augmented in LTA-stimulated cells, whereas no such effect was observed upon stimulation with calcium hydroxide pretreated LTA. Mass spectrometry showed that intact glycolipids of LTA yielded distinct mass peaks at 930 to 1,070 mass over charge (m/z) units, corresponding to dihexosyl-diacylglycerol consisting of two acyl chains with chain lengths of C(16) to C(22) and with one or two unsaturated double bonds. However, those peaks were not observed in the mass spectra of the calcium hydroxide-treated LTA. Furthermore, free fatty acids released from the calcium hydroxide-treated LTA were detected using TLC. Conclusion: We suggest that calcium hydroxide attenuates the inflammatory activity of E. faecal is LTA through deacylation of the LTA. (J Endod 2011;37:191-196) ; Supported by grants from Korea Research Foundation funded by the Korean Government (KRF-2008-314-E00223), from the National Research Foundation of Korea (NRF) grant funded by the Korea government (MEST) (No. 2010-0029116), and from a Science Research Center grant to the Bone Metabolism Research Center (20100001746) funded by the Korean Ministry of Education, Science and Technology, Republic of Korea. ; 1

Chlorhexidine gluconate (CHX) has been widely used as a canal irrigant or an intracanal medicament on account of its antibacterial substantivity. This in vitro study aimed to determine if CHX attenuates the inflammatory activity of Enterococcus faecalis and its major virulence factor, lipoteichoic acid (LTA). An enzyme-linked immunosorbent assay showed that CHX-killed E. faecalis was less potent than heat-killed E. faecalis in the production of tumor necrosis factor α (TNF-α) by a murine macrophage cell line, RAW 264.7 (p < 0.05). Interestingly, pretreatment of LTA with 2% CHX for 6 hours or with 0.2% CHX for 24 hours almost eliminated the TNF-α inducibility (p < 0.05). Furthermore, CHX abrogated the ability of LTA to stimulate Toll-like receptor 2, resulting in the attenuated induction of TNF-α expression. Collectively, our results suggest that CHX can inactivate LTA of E. faecalis leading to the alleviation of inflammatory responses induced by E. faecalis and its LTA. ; Supported by the Korea Research Foundation Grant funded by the Korean Government (KRF-2008-314-E00223) and by a grant (03-2007-0090) from the Seoul National University Dental Hospital Research Fund, Republic of Korea.