• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제37권4호
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• pp.301-311
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• 2011

Introduction: This study examined the effect of the application of low intensity pulsed ultrasound on bone healing after an injection of adipose tissue-derived stem cells (ADSCs) during the implantation of a titanium implant in the tibia of diabetes-induced rats. Materials and Methods: Twelve Sprague-Dawely rats were used. After inducing diabetes, the ADSCs were injected into the hole for the implant. Customized screw type implants, 2.0 mm in diameter and 3.5 mm in length, were implanted in both the tibia of the diabetes-induced rats. After implantation, LIPUS was applied with parameters of 3 MHz, 40 mW/$cm^2$, and 10 minutes for 7 days to the left tibiae (experimental group) of the diabetesinduced rats. The right tibiae in each rat were used in the control group. At 1, 2 and 4 week rats were sacrificed, and the bone tissues of both tibia were harvested. The bone tissues of the three rats in each week were used for bone-to-implant contact (BIC) and bone area (BA) analyses and the bone tissues of one rat were used to make sagittal serial sections. Results: In histomorphometric analyses, the BIC in the experimental and control group were respectively, $39.00{\pm}18.17%$ and $42.87{\pm}9.27%$ at 1 week, $43.74{\pm}6.83%$ and $32.27{\pm}6.00%$ at 2 weeks, and $32.62{\pm}11.02%$ and $47.10{\pm}9.77%$ at 4 weeks. The BA in experimental and control group were respectively, $37.28{\pm}3.68%$ and $31.90{\pm}2.84%$ at 1 week, $20.62{\pm}2.47%$ and $15.64{\pm}2.69%$ at 2 weeks, and $11.37{\pm}4.54%$ and $17.69{\pm}8.77%$ at 4 weeks. In immunohistochemistry analyses, Osteoprotegerin expression was strong at 1 and 2 weeks in the experimental group than the control group. Receptor activator of nuclear factor kB ligand expression showed similar staining at each week in the experimental and control group. Conclusion: These results suggest that the application of low intensity pulsed ultrasound after an injection of adipose tissue-derived stem cells during the implantation of titanium implants in the tibia of diabetes-induced rats provided some positive effect on bone regeneration at the early stage after implantation. On the other hand, this method is unable to increase the level of osseointegration and bone regeneration of the implant in an uncontrolled diabetic patient.

• Clinical and Experimental Reproductive Medicine
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• 제26권1호
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• pp.9-20
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• 1999

The genetic defects in human gametes and embryos can cause adverse effects on overall reproductive events. Biopsy of embryos for preimplantation genetic diagnosis (PGD) offers a new possibility of having children free of the genetic disease. In addition, advanced embryo culture method may enhance the effectiveness of embryo biopsy for the practical application of PGD. This experimental study was undertaken to evaluate the effects of coculture on the development in vitro of biopsied mouse embryos as a preclinical model for PGD of human embryos. Embryos were obtained after in vitro fertilization (IVF) from F1 hybrid mice (C57BLfemale/CBAmale). Using micromanipulation, 1, 2, 3 or 4 blastomeres of 8-cell stage embryos were aspirated through a hole made in the zona pellucida by zona drilling (ZD) with acidic Tyrode's solution (ATS). After biopsy of blastomeres, embryos were cultured in vitro for 110 hours in Ham's F-10 supplemented with 0.4% BSA or cocultured on the monolayer of Vero cells in the same medium. The frequence of blastocyst formation were recorded, and the embryos beyond blastocyst stage were stained with 10% Giemsa to count the total number of nuclei in each embryo. There was no significant difference in the blastocyst formation between the zona intact control group and the zona drilling (ZD) only, or biopsied groups. The hatching rate of all the treatment groups except 4/8 group was significantly higher than that of control group. In all the treatment groups, there was a significant reduction in the mean cell number of embryos beyond blastocyst stage ($50.2{\pm}14.0$ in control group vs. $41.2{\pm}7.9$ in ZD, $39.3{\pm}8.8$ in 7/8, $29.7{\pm}6.4$ in 6/8, $25.1{\pm}5.7$ in 5/8, and $22.1{\pm}4.3$ in 4/8 groups, p<0.05). When the same treatments were followed by coculture with Vero cells, a similar pattern was seen in the blastocyst formation and the hatching rate. However, in all the treatment groups, there was a significant increase in the mean cell number of embryos beyond blastocyst stage with coculture, compared with the parallel groups without coculture. In the cleavage rate of biopsied blastomeres cultured for 110 hours after IVF, there was no significant difference between coculture and non-coculture groups (87.2% vs. 78.7%). However, the mean cell number of embryos developed from the biopsied blastomeres was significantly higher in coculture group ($11.5{\pm}4.7\;vs.\;5.9{\pm}1.9$, p<0.05). In conclusion, biopsy of mouse embryos after ZD with ATS is a safe and highly efficient method for PGD, and coculture with Vero cells showed a positive effect on the development in vitro of biopsied mouse embryos and blastomeres as a preclinical model for PGD of human embryos.

• 지능정보연구
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• 제20권1호
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• pp.177-193
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• 2014

개인정보 분야에서의 다양한 정보 보안 이슈가 발생함에 따라 해당 분야의 전문가를 확인하기 위한 프레임워크는 매우 중요한 영역이 되었다. 전문가 탐색과정은 주로 연구 업적 등을 통한 주관적인 평가가 일반적이지만 보다 객관적인 방식을 통한 선정이 매우 중요하다. 소셜 네트워크 분석기법의 응용이 다양한 영역에서 활용됨에 따라 본 연구는 개인정보보호분야의 전문가를 확인하고 해당 전문가들의 연구실적을 판단하기 위한 분석 프레임워크를 제시하고자 하였다. 본 연구는 연구 목적에 따라 개인정보보호 연구영역의 연구성과 자료를 바탕으로 소셜 네트워크 분석을 실시하고 핵심연구자의 성과를 분석하였다. 수집된 데이터는 연구의 공저자, 발행기관, 소속기관 등의 네트워크 구성에 활용되어 핵심전문가 집단을 관리하기 위한 프레임워크를 제시하였다. 본 연구는 NDSL에서 최근 5년 동안 발표된 논문들을 중심으로 자료를 수집하였다. 연구자들이 학술 정보를 교환하는 정기 간행물인 학술지를 바탕으로 연구 네트워크를 형성하는 네트워크 자료를 수집함으로써 연구활동에 대한 정보를 분석할 수 있었다. 일반적으로 연구자들은 연구 결과를 논문으로 발표하고, 발표된 논문들이 다수의 관련 분야 전문가들에게 공유된다는 점에서 학술연구지는 연구자들의 지식관련 의사소통 공간이며 지식의 구조화에 핵심적인 역할을 수행한다. 그에 따라 본 연구의 연구 대상 분야로 설정한 개인정보보호 분야의 연구 구조를 이해하기 위해 국내에서 발표된 관련 분야의 논문들을 연구 대상으로 자료가 수집되었다. 특히 자료의 선별 기준은 국내 최대의 데이터베이스를 보유하고 있는 NDSL에서 개인정보보호 관련 키워드를 보유한 논문 데이터를 수집 및 정제하여 분석 자료로 사용하였다. 2005년부터 2013년까지 약 2,000개의 연구결과 중 주제 관련성, 공저자 추출 등을 수집하였다. 데이터 수집 이후 연구 분석을 위한 데이터 처리를 통하여 통해 총 784개의 논문을 선정하고 분석대상으로 확정하였다. 분석 결과, 개인정보보호 연구영역의 전문가 집단을 이용한 연구논문 성과에 대한 분석은 핵심 연구자들을 추출해내고 전문가 집단을 관리하는 데 도움을 제공할 수 있다. 특히 소속집단 및 연구논문 발행기관을 분석함으로써 개인정보보호 연구영역에서 확인되지 않았던 연구자들의 연구 논문 게재의 공저자 네트워크가 매우 밀접함을 확인할 수 있다. 또한 연구논문의 발행기관 및 소속집단의 특성을 추출함으로써 개인정보보호 영역의 전문가 평가지표로서 소셜 네트워크 지표들의 활용가능성을 확인하였다.