• 건강소식
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• v.35 no.12
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• pp.16-17
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• 2011

골다공증은 골강도에 문제가 생겨서 골절 위험이 커지는 질환이다. 골강도는 골밀도와 골의 질로 결정되는데, 골강도의 70%는 골량 즉, 골밀도에 의존한다. 따라서 골밀도는 골다공성 골절을 가장 잘 예측할 수 있는 지표가 된다.

• Journal of Biomedical Engineering Research
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• v.23 no.6
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• pp.451-458
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• 2002

Osteoporosis is a systemic skeletal disease caused by low bone mass and the decrease of bone density in the microstructure of trabecular bone. Drug therapy(PTH Parathyroid hormone) may increase the trabecular thickness and thus bone strength. Vertebroplasty is a minimally invasive surgery foy the treatment of osteoporotic vertebral compression fracture. This Procedure includes Puncturing vertebrae and filling with Polymethylmethacrylate(PMMA). Although altering recommended monomer-to-Powder ratio affects material properties of bone cement, clinicians commonly alter the mixture ratio to decrease viscosity and increase the working time. The Purposes of this study were to analyze the effect of 4he monomer-to-powder ratio on the mechanical characteristics of trabecular. In this paper, the finite element model of human vertebral trabecualr bone was developed by modified Voronoi diagram, to analyze the relative effect of hormone therapy and vertebroplasty at the treatment of osteoporotic vertebrae. Trabeuclar bone models for vertebroplasty with varied monomer-to-Powder ratio(0.40∼1.07 ㎖/g) were analyzed. Effective modulus and strength of bone cement-treated models were approximately 60% of those of intact models and these are almost twice the values of hormone-treated models. The bone cement models with the ratio of 0.53㎖/g have the maximum modulus and strength. For the ratio of 1.07㎖/g, the modulus and strength were minimum(42% and 49% respectively) but these were greater than those for drug therapy. This study shows that bone cement treatment is more effective than drug therapy. It is found that in vertebroplasty, using a monomer-to-powder ratio different from that recommended by manufacturer nay significantly not only reduce the cement's material Properties but also deteriorate the mechanical characteristics of osteoporotic vertebrae.

• Journal of Acupuncture Research
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• v.19 no.5
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• pp.219-233
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• 2002

면역억제활성이 알려진 Cerves korean TEMMINCK var. manchur-icus Swinhoe(Nokyong) 약침(CPH)은 다모 뿔의 녹용을 열수추출한 용액이다. 본 연구에서는 녹용 약침의 효과를 adjuvant 유발 관절염 실험용쥐를 이용하여 골체, 골강도 및 골대체율의 감소를 평가하였다. 위의 골 대사 관련 검정실험을 위하여 6주령의 암컷 실험용쥐에 20일간 약물투여를 실시하였다. 실험적인 관절염유발은 실험용쥐의 뒤쪽 다리에 Adjuvant를 주사하여 유발시킨 결과, 요부의 골 무기질함량과 밀도(BMC, BMD) 그리고 압축강도는 관절염 실험용쥐에서 감소되었다. 10일 경과 후 골형성도(BFR/BS, BFR/BV)의 조직형태학적 기준척도인 혈청 osteocalcin 수가 정상대조군과 비교해 볼 때 현저하게 감소되었다. 그러나, 몸무게로 나눈 BMC치는 관절염 유발군과 정상군 사이에 큰 차이가 보이지 않았다. 그리고 골무기질 함량은 정상군에 비해 감소하지 않았다. 20일 경과후 몸무게로 나누거나 나누지 않은 BMC치 모두, 관절염 군에서 요부 몸체의 골무기질 함량과 강도가 정상군과 비교해 볼 때 현저하게 감소되었다. 잔존 소주(小柱)의 무기질 침착 표면은 현저하게 감소하였으며 파골 세포의 수는 증가하였다. 초기부터 매일 Shinsu(B23)에 CPH 약침 투여(10, 20, $50{\mu}g/kg$)는 20일 경과후 만성적인 다리 부종을 현저하게 방지하였으며, 골 무기질함량, 골강도 및 소주골 형성등의 감소와 파골세포수 증가도 완화하였다. Adjuvant주사로 장애를 받았던 연령대비 요부 길이 증가도 유지되었다. 이러한 결과는 Adjuvant에 의한 관절염 실험용쥐의 2차적인 골관절염에서 충분히 요추 몸체뼈와 강도 감소를 나타내기 위해서는 적어도 20일이 필요하다는 것을 제시하였다. 본 결과로부터 CPH가 실험용쥐의 관절염에 대한 골체, 골강도 및 골대체율을 조절하는데 유효하게 작용하고 있음을 알 수 있었다.

• Journal of Biosystems Engineering
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• v.29 no.4
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• pp.347-356
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• 2004

치아인회석, 키토산, 시아노아크릴레이트 등의 생분해성 생체재료를 이용해 새로운 생체흡수성 골시멘트를 개발하고자 하였다. 이들 골시멘트들에 대해서 중합온도, 응고시간 등의 조작특성과 압축강도, 전단강도 등의 물성을 분석하였다. 특히, 치아인회석과 키토산의 미립가루와 부틸 시아노아크릴레이트의 강력접착제를 이용한 시멘트(B)에 대해서는 직접 접촉방법과 XTT 방법을 통해 세포독성을 분석하였고, 또한 쥐를 이용한 동물실험에서 시멘트(B)의 처리그룹에 따라 생체적합성을 분석하였다. 시아노아크릴레이트를 이용한 골시멘트의 최대중합온도는 약 33$^{\circ}C$, 조작(응고)시간은 3-6분, 압축강도는 약 15-25㎫, 전단강도는 약 0.4-l.7 ㎫를 나타내었다. 첨가제로 사용된 Lipiodol은 골시멘트의 주사성과 강력접착제의 초기 중합지연도를 높였고, 특히 송진가루는 시아노아크릴레이트의 초기중합을 지연시켰다. 시아노아크릴레이트를 이용한 시멘트(B)의 세포독성을 분석한 결과, 대부분의 처리 그룹에서 낮게 나타났고, 특히 키토산과 치아인회석을 사용한 경우 각각 세포 독성이 더 낮게 나타났다. 그리고 골시멘트(B)의 동물 생체적합성 실험의 방사선상 및 조직학적 분석에서도 뼈 형성 및 결합이 우수하게 나타났다.

• The Journal of the Korea Contents Association
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• v.9 no.10
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• pp.218-226
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• 2009

This study conducted the following experiment to examine effects of bone metabolism on aquatic exercise, Drynariae Rhizoma and aquatic exercise with Drynariae Rhizoma. This experiment was conducted to compare bone strength, bone mineral density, weight, change of femur, osteocalcin, ALP, Ca and P effects by aquatic exercise for 6 weeks, Drynariae Rhizoma and Drynariae Rhizoma for aquatic exercise with 40 SD rats of postoophorectomy osteoporosis and it divided 10 subjects. experiment group (I) is applying postoophorectomy osteoporosis group, (II) is applying aquatic exercise group, (III) is applying Drynariae Rhizoma group and (IV) is applying aquatic exercise with Drynariae Rhizoma group. These result lead us to the conclusion that osteocalcin were showed a statically increase and blood Ca level were showed a statically decrease on other groups compare to group(I). Consequently, aquatic exercise and Drynariae Rhizoma would be lead to increment of bone metabolism on postoophorectomy osteoporosis.

• Food Engineering Progress
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• v.14 no.2
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• pp.106-111
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• 2010

In this study, we performed corrugation fluting experiments to examine the relationship between high-low corrugation of a corrugated medium and compressive strength of corrugated containers for food packaging. A low-grade corrugated medium was found to suffer from weak tensile resistance and to be prone to stealing, which tends to produce low corrugation. In contrast, a medium with a large corrugation deviation often caused slimming during fluting and produced irregular corrugations. Experiments of high-low corrugation distribution according to corrugated medium grades indicate that a high grade medium shows a smaller ratio of low corrugation. The thickness of corrugated fiberboard is weakly correlated to the basis weight of medium, yet positively correlated to the medium thickness (y=3.9732x+4.2712, $R^{2}=0.8142$) and inversely proportional to the medium density (y=-3.1213x+6.8736, $R^{2}=0.9919$). Compressive strength of a corrugated fiberboard box is low, if made of corrugated medium with large low corrugation distribution. Compressive strength showed 13% variation with respect to medium grades and 21% variation for various test samples. The corrugation fluting of a corrugated medium is related to physical properties such as basis thickness and density.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.26 no.4
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• pp.363-368
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• 2000

The purposes of the study was to examine changes in thickness and strength of the rat femur after administration of sodium fluoride in the drinking water. 48 female Sprague-Dawley rats were randomly divided into 4 groups, and they were supplied with 0(control), 1, 5 and 50 ppm of fluoride in the drinking water ad libitum for 6 weeks. Rats were killed and both sides of femur were dissected. Bone strength was measured as the stress of failure of femur at the middle point and femoral neck with Instron. Histologic slides were prepared from the femur shaft with routine processing of fixing, demineralizing, embedding and HE staining. Thickness and area of cortical bone and medullary cavity were measured by using Camera Lucida and Image Analyzer. All the collected data were analyzed with one-way ANOVA, Duncan's multiple range test for post-hoc tests and ANCOVA using the SAS 6.12 package at the level of 0.05. Bone strength increased significantly in the animals given 1 and 5 ppm of fluoride in the water, as compared to the control group. There were significant decreases of stress at fracture in 50 ppmF group compared to the 1 and 5 ppmF groups. The similar trends of bone strength at the femoral neck fracture test, but there were no statistical significances. Cortical bone thickness and area of the femur increased in the 1 and 5 ppmF groups compared to the control. However, the thickness of 50 ppmF group also decreased significantly as compared to 1 and 5 ppmF groups. On the other hand, medullary thickness and area increased in all fluoride groups than control group. All of the findings presented support the conclusion that, low fluoride dosage used in water fluoridation could increase the bone strength and might have preventive effect on femur fracture.

• 대한관절경학회:학술대회논문집
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• 2007.10a
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• pp.91-91
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• 2007

• Journal of Life Science
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• v.14 no.3
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• pp.385-390
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• 2004

Chitosan is abundant polysaccharide polymer in nature Chitosan has been the subject of much research regarding its potential as a nutritional adjunct and pharmaceutical ingredient. In the present study, we examined fracture-healing process with chitosan administration and low calcium diet in rats. Left femur was fractured and fixed with intramedullary pin. The rats were fed normal diet or low calcium diet and administered chitosan with the doses of 0, 50, 100 and 150ng/ml orally 5 times a week for 10 weeks. Soft X-ray and mechanical testing of all fractured femora was taken. Radiographical finding showed that the callus formation and process of fracture healing was present in all the fractured femora. Mechanical testing indicated that the maximum load and stiffness of femur in rat fed low calcium diet was lower than those of that in rat fed normal diet. No difference in maximum load and stiffness of fractured femora in chitosan treated rat were observed as compared to vehicle treated rat. Chitosan or/and low calcium diet did not affect the ratio of fractured/unfractured femur about maximum load and stiffness. The results suggest that chitosan dose not affect the bone mechanical strength and the process of fracture healing. Low calcium diet does decrease the bone mechanical strength.

• Journal of the Korea Society of Computer and Information
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• v.12 no.5
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• pp.285-292
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• 2007

This study was developed the metallic plate for fixation in the femur fracture for the orthopedic region and rigid fixation with plates has a firm place in fracture treatment. Most plates can be used for rigid as well as biological and dynamical fracture fixation. The device's designation and sizing has a specific with bending structural stiffness and strength, known meaning that is reliable regardless of the plate by the short type and long type. Short plate have a wrapping of femur and long plate have to preserve a pole of femur. The bending strength of the curved metallic long plate has to evaluate a 11,000N and The bending strength of the curved metallic short plate has to evaluate a 6,525N. The tensile stress through to press a plate is $1573N/m^2\;and\;1539N/m^2$. The device can be used to support Revision case of Hip Implant and to use a case of Hip screw compression of Hip Neck Fracture.