Bioabsorbable bone plates enabled with local, sustained delivery of alendronate for bone regeneration

Hur, W.,Park, M.,Lee, J.Y.,Kim, M.H.,Lee, S.H.,Park, C.G.,Kim, S.N.,Min, H.S.,Min, H.J.,Chai, J.H.,Lee, S.J.,Kim, S.,Choi, T.H.,Choy, Y.B. Elsevier Science Publishers 2016 Journal of controlled release Vol.222 No.-

<P>We prepared a bone plate enabled with the local, sustained release of alendronate, which is a drug known to inhibit osteoclast-mediated bone resorption and also expedite the bone-remodeling activity of osteoblasts. For this, we coated a bone plate already in clinical use (PLT-1031, Inion, Finland) with a blend of alendronate and a biocompatible polymer, azidobenzoic acid-modified chitosan (i.e., Az-CH) photo-crosslinked by UV irradiation. As we performed the in vitro drug release study, the drug was released from the coating at an average rate of 4.03 mu g/day for 63 days in a sustained manner. To examine the effect on bone regeneration, the plate was fixed on an 8 mm cranial critical size defect in living rats and the newly formed bone volume was quantitatively evaluated by micro-computed tomography (micro-CT) at scheduled times over 8 weeks. At week 8, the group implanted with the plate enabled with sustained delivery of alendronate showed a significantly higher volume of newly formed bone (52.78 +/- 6.84%) than the groups implanted with the plates without drug (23.6 +/- 3.81%) (p < 0.05). The plate enabled with alendronate delivery also exhibited good biocompatibility on H&E staining, which was comparable to the Inion plate already in clinical use. Therefore, we suggest that a bone plate enabled with local, sustained delivery of alendronate can be a promising system with the combined functionality of bone fixation and its expedited repair. (C) 2015 Elsevier B.V. All rights reserved.</P>

볏짚의 사료가치 증진을 위한 적정 알카린 H2O2 처리 수준에 관한 연구

문양수(Y . S . Moon),하종규(J . K . Ha),고종열(J . Y . Ko),최연호(Y . H . Choy),조경훈(G . H . Cho),최윤재(Y . J . Choi),한인규(I . K . Han) 한국축산학회 1990 한국축산학회지 Vol.32 No.10

This study was carried out to determine the adequate levels of alkaline hydrogen peroxide treatment for the improvement of nutritive value of rice straw. In vitro digestibility and chemical analysis after several treatments were measured. Treatment variables were soaking time(12, 24, 48 and 96 hrs), temperature(5, 25, 50 and 75℃) of alkaline H₂0₂ solution, H₂0₂ concentration (0.5, 1, 2, 3 and 4%) and substrate /solution ratio (1, 2, 3, 4 and 5g/ml). The results obtained were summarized as follows. 1. The DM digestibilities or rice straw treated with H₂O₂ for 24 and 48 hours were higher than those of the others(p$lt;0.05). There was no differ ences when the rice straw was treated for 12, 72 or 96 hours. Cell wall contents were not affected by the time of treatment. 2. The DM digestibilities were higher at pH 11.5 or above(p$lt;0.05) and was decreased as pH declined. When rice straw was treated with H₂O₂ at pH 11.5 or higher, NDF, ADF and cellulose contents were increased. However, lignin content and DM recovery percentages were decreased. 3. The DM digestibilities were not influenced by the ratio of straw versus liquid. The contents of NDF and cellulose were not affected up to the ratio of 4g rice straw/50m1, but were decreased at 5g rice straw/50m1. Lignin content and DM recovery percentages, however, were increased at 5g rice straw /50m1. 4. The DM digestibilities were not different among treatments at 5, 25 and 50℃. However, the rice straw treated at 75℃ showed lowest digestibility of all treatment (p$lt;0.05). The content of NDF, ADF and cellulose was increased by increasing temperature. However, lignin content and DM recovery percentages were decreased by increasing temperature. 5. The AHP treated rice straw had higher content of ADF and cellulose, and lower content of hemicellulose and lignin as the concentration of H₂O₂, increased. But hemicellulose, lignin and DM recovery percentages were decreased. The NDF content was not different among five different concentrations of H₂0₂ solution. In conculsion, based upon the results of present experiments the most desirable method is to soak rice straw in 1% alkaline H₂0₂ solution at pH 11.5, at room temperatrve (25℃), for 24∼48 hours and at the ratio of 4g rice straw /50m1 solmtion.

대학생의 스마트폰 중독, 불안 및 수면의 질에 대한 연구

김민지,염영은,전지은,조현정,최수민,계향미,김가현,남은재,박신영,박지영 이화여자대학교 간호과학대학 2014 이화간호학회지 Vol.- No.48

Purpose: The purpose of this study was to learn about smartphone addiction level, anxiety, and sleep quality among undergraduate students. Method: In this cross-sectional design study, a convenient sample of 231 undergraduate students were recruited between August and September, 2013. Questionnaires used for this study were the Smartphone addiction proneness scale for adults, the STAI (State-Trait Anxiety Inventory), and the PSQI (Pittsburgh Sleep Quality Index). Data were statistically analyzed using descriptive statistics, t-test, Pearson’s correlation, and ANOVA. Result: About 44 percent of the participants used smartphones in order to communicate with others; SNS (Social Network Service) was the most frequently used function among participants. 59 participants (25.5%) were smartphone addiction potentially risk group and 22 participants (9.5%) were high-risk group. Sex and amount of time used per day had significant influences on smarphone addiction score. There were statistically significant relationships among smartphone addiction level, anxiety, and quality of sleep. The smartphone addiction high-risk group had significantly higher trait anxiety scores compared to the normal group. Conclusion: Smartphone addiction was a risk factor for both anxiety and quality of sleep among undergraduate students. The proposals of this study are as follows: first, in-depth studies are required with regard to the intervention for high frequency of smartphone use and the influence of smartphone addiction as a risk factor of anxiety and mental health. Second, a smartphone addiction treatment program should be supplemented as one of the interventions for anxiety. Third, as an intervention for sleep quality, not only should sleep patterns be considered, but one’s behaviors or habits should be taken into account, particularly at the level of smartphone addiction and anxiety.

농용 트랙터 안전캡 현가 장치의 최적 설계

최현준,김경욱,김종언 한국농업기계학회 1998 바이오시스템공학 Vol.23 No.4

韓牛 牝牛의 Body Condition Score가 繁殖形質에 미치는 影響

최성복,최연호,이지웅,백광수,김영근,손삼규,김내수 한국동물자원과학회 2004 한국축산학회지 Vol.46 No.1

Data from five Hanwoo breeding farms were collected to analyze the effects of parity, season, nutrition and reproduction on body conditions of heifers and cows and to analyze the relationships of body conditions with reproductive performances and body growth. Analytic models included farms and parity which were run through SAS to estimate least squares means and correlation coefficients between traits - body condition scores(BCS) of 1(very emaciated) through 9(very obese) scale at service and at calving, calving interval, days to rebreeding, gestation length, number of services per conception. Overall averages were 4.55 for BCS at service, 5.42 for BCS at calving, 406.7days of calving interval, 287.7days of gestation length, 66.2days from calving to first service and 1.78 times of services per conception. Number of services per conception was 1.50~1.74 times for the cows of BCS 5 or under and 2.00~3.00 for those of BCS 6 or higher. Body weight of calves from cows observed averaged 23.3㎏ at birth and 70.7㎏ at weaning. 57 percent of cows showed BCS 4~5 at service while 46 percent of those showed 5~6 at calving. Extimated phenotypic correlation coefficients of BCS at service with BCS at calving, calving interval, gestation length, number of services per conception were low but positive: 0.16, 0.26, 0.08 and 0.06, respectively. Phenotypic correlations of BCS at calving with calving interval, gestation length and number of services per conception were estimated to be also low and positive: 0.10, 0.13 and 0.10, respectively. However, phenotypic correlation between calving interval and gestation length, and between gestation length and number of services per conception were negative but low as - 0.11 and -0.13 each.

Intracrystalline structure and release pattern of ferulic acid intercalated into layered double hydroxide through various synthesis routes

Kang, H.,Kim, H.J.,Yang, J.H.,Kim, T.H.,Choi, G.,Paek, S.M.,Choi, A.J.,Choy, J.H.,Oh, J.M. Elsevier 2015 Applied clay science Vol.112 No.-

We intercalated ferulic acid (FA) molecules into a layered double hydroxides (LDHs) via three different synthesis routes-ion-exchange, exfoliation-reassembly, and reconstruction-to obtain FA-LDH nanohybrids. All the nanohybrids started from same MgAl-CO<SUB>3</SUB>-LDH pristine, with a homogeneous particle size of 80nm, in order to control particle size of final products. According to infrared spectroscopy, all the synthesis routes resulted in successful hybridization between anionic ferulate and positive LDH layers. X-ray diffraction, UV-Vis spectroscopy and thermal analyses showed that the FA molecules were arranged in a zig-zag manner to maximize π-π interactions among them. From scanning electron microscopy, it was revealed that reconstruction gave rise to structural re-organization of LDH layers resulting in a house-of-cards morphology in the nanohybrid, while other methods produced a hexagonal plate-like shape. It seems that FA moieties intercalated by a reconstruction method could be accommodated in the inter-particle cavity as well as the interlayer space in FA-LDH nanohybrids. We investigated time-dependent FA release profiles from each nanohybrid in deionized water and saline. The release patterns and kinetic model fitting results revealed that the release behavior was different each nanohybrid according to the synthesis method and followed Elovich and power function models.

Genetic Models for Carcass Traits with Different Slaughter Endpoints in Selected Hanwoo Herds I. Linear Covariance Models

Choy, Y.H.,Lee, C.W.,Kim, H.C.,Choi, S.B.,Choi, J.G.,Hwang, J.M. Asian Australasian Association of Animal Productio 2008 Animal Bioscience Vol.21 No.9

Carcass characteristics data of Hanwoo (N = 1,084) were collected from two stations of the National Livestock Institute of Animal Science (NIAS), Korea and records from thirteen individual cow-calf operators were analyzed to estimate variance and covariance components and the effect of different slaughter endpoints. Carcass traits analyzed were cold carcass weight (CWT, kg), REA (rib eye area, cm2), back fat thickness (mm) and marbling score (1-7). Four different models were examined. All models included sex and contemporary group as fixed effects and the animal's direct genetic potential and environment as random effects. The first model fitted a linear covariate of age at slaughter. The second model fitted both linear and quadratic covariates of age at slaughter. The third model fitted a linear covariate of body weight at slaughter. The fourth model fitted both linear covariates of age at slaughter and body weight at slaughter. Variance components were estimated using the REML procedure with Gibb's sampler. Heritability estimate of CWT was in the range of 0.08-0.11 depending on the model applied. Heritability estimates of BF, REA and MS were in the ranges of 0.23-0.28, 0.19-0.26, and 0.44-0.45, respectively. Genetic correlations between CWT and BF, between CWT and REA, and between CWT and MS were in the ranges of -0.33 - -0.14, 0.73-0.84, and -0.01- 0.11, respectively. Genetic correlations between REA and BF, between MS and BF and between REA and MS were in the ranges of -0.82 ~ -0.72, 0.04~0.28 and -0.08 ~ -0.02, respectively. Variance and covariance components estimated varied by model with different slaughter endpoints. Body weight endpoint was more effective for direct selection in favor of yield traits and body weight endpoints affected more of the correlated response to selection for the traits of yield and quality of edible portion of beef.

Inorganic–Biomolecular Hybrid Nanomaterials as a Genetic Molecular Code System

Choy, J.-H.,Oh, J.-M.,Park, M.,Sohn, K.-M.,Kim, J.-W. WILEY-VCH Verlag 2004 ADVANCED MATERIALS Vol.16 No.14

<B>Graphic Abstract</B> <P>A molecular-level coding method utilizing DNA base pairs as code units has been systemized. The system consists of four steps: encoding, encrypting, decrypting and decoding (see Figure), which are realized by tailor-made nanohybrids (DNA–layered double hydroxide (LDH) and polypyrrole–maghemite). The nanohybrids give solutions to the inherent problems which hamper DNA molecular code systems; stability in encrypting and rapidity in analysis. <img src='wiley_img/09359648-2004-16-14-ADMA200400027-content.gif' alt='wiley_img/09359648-2004-16-14-ADMA200400027-content'> </P>

Evolution of Interface Voids under Current and Temperature Stress in Integrated Circuit Metallization

J. H. Choy,K. L. Kavanagh,Y. C. Kim 대한금속학회 2004 METALS AND MATERIALS International Vol.10 No.5

Application of RAPD Methods in Meat for Beef Breed Identification

Choy, Y.H.,Oh, S.J.,Kang, J.O. Asian Australasian Association of Animal Productio 2001 Animal Bioscience Vol.14 No.12

Bovine genome samples were collected from meat of three different beef breeds (Hanwoo, Holstein and imported beef breed) that are commercially merchandized in Korean beef market. Operon B (OPB)-kits were used as random primers (3, 7, 10, 11, 12, 14) in random amplified polymorphic DNA (RAPD) method on whole genome. Each primer provided characteristic bands that were highly polymorphic. Each single primer could provide relatively efficient polymorphic band patterns among breeds. However, use of two or more primers in combination is recommended to improve resolution of experiments with higher molecular weight bands of DNA. In our experiments, OPB-11 resolved well between beef cattle breeds and Holstein. And OPB-7, 12 and 14 could be combined with OPB-11 to identify Hanwoo beef from the other two kinds of beef.