• Animal cells and systems
• /
• 제13권4호
• /
• pp.363-370
• /
• 2009

Since vitamin $D_3$ is an important regulator of osteoblastic differentiation, a presently-established vitamin $D_3$-entrapped calcium phosphate film (VCPF) was evaluated for hard tissue engineering. The entrapped vitamin $D_3$ more rapidly induced bone nodule formation. To characterize the cellular events leading to regulations including faster differentiation, signal transduction pathways were investigated in osteoblastic MG63 cells at a molecular level. Major signaling pathways for MG63 cell proliferation including phosphatidylinositol-3-kinase, extracellular signal-regulated kinase, c-Jun N-terminal kinase and focal adhesion kinase pathways were markedly down-regulated when cells were cultured on calcium phosphate film (CPF) and VCPF. This agreed with our earlier observations of the immediate delay in proliferation of MG63 cells upon culture on CPF and VCPF. On the other hand, the p38 mitogen-activated protein kinase (p38 MAPK) and protein kinase A (PKA) pathways were significantly up-regulated on both CPF and VCPF. CPF alone could simulate differential behaviors of MG63 cells even in the absence of osteogenic stimulation and entrapment of vitamin $D_3$ within CPF further amplified the signal pathways, resulting in continued promotion of MG63 cell differentiation. Interplay of p38 MAPK and PKA signaling pathways likely is a significant event for the promotion of differentiation and mineralization of MG63 cells.

• 폴리머
• /
• 제33권3호
• /
• pp.248-253
• /
• 2009

의료용으로 적용될 수 있는 새로운 재료를 제조하기 위하여 폴리카프로락톤(PCL)과 양친성 구조를 갖는 폴리(에틸렌 글리콜)(PEG)이 그래프트된 PCL을 이용하여 생분해성 블렌드를 제조하였다. 제조된 블렌드는 PCL을 기본으로 하고 여기에 그래프트 공중합체의 함량을 변화시키며 열적 그리고 결정화 특성을 관찰하였다. 그래프트 공중합체의 함량 변화에 따라 결정화 온도의 변화 및 결정화 속도가 변화하였고 이를 통해 그래프트 공중합체가 PCL의 결정화 거동에 영향을 미침을 확인하였다. 이는 광학현미경을 통한 결정의 교대 소광 밴드의 관찰을 통하여서도 확인할 수 있었다. 약물방출시스템과 같은 의료용 응용을 고려하여 블렌드 필름의 흡수거동과 단백질 흡착에 대한 특성도 평가하였다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제16권4호
• /
• pp.588-595
• /
• 2003

The optimum level of fresh granulated low-calcium (0.2%) skim milk co-precipitate, as fat substitute in low-fat ground pork patties was determined on the basis of physico-chemical, cooking and sensory properties. Low-fat ground pork patties (<10% total fat), formulated with 15 per cent water, 4 per cent added fat, 1.5 per cent salt and 4-10 per cent milk co-precipitate, were evaluated for proximate composition, cooking characteristics and compared with control patties with 15 % added fat. The moisture and protein content of raw and cooked low-fat patties were significantly (p<0.05) higher than control. The incorporation of milk co-precipitate in low-fat patties improved cooking yield, fat and moisture retention and reduced shrinkage. The sensory properties of low-fat patties were comparable with control patties. The overall acceptability of low-fat patties formulated with 7% milk co-precipitate was significantly (p<0.05) higher than patties with 10% level and non-significantly (p<0.05) higher than low-fat patties containing 4% milk co-precipitate and control. Instrumental Texture Profiles of developed low-fat patties and control patties were comparable with slight increases in hardness and gumminess of the low-fat product. The developed low-fat ground pork patties (7% milk co-precipitate) had lower TBA values, better microbiological and sensory refrigerated storage stability than high-fat control patties packaged in air permeable films for 21 days.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
• /
• pp.223.2-223.2
• /
• 2015

Polyurethane acrylate (PUA) has been introduced to utilize as a mold material for sub-100 nm lithography as it provides advantages of stiffness for nanostructure formation, short curing time, flexibility for large area replication and transparency for relevant biomedical applications. Due to the ability to fabricate nanostructures on PUA, there have been many efforts to mimic extracellular matrix (ECM) using PUA especially in a field of tissue engineering. It has been demonstrated that PUA is useful for investigating the nanoscale-topographical effects on cell behavior in vitro such as cell attachment, spreading on a substrate, proliferation, and stem cell fate with various types of nanostructures. In this study, we have conducted surface modification of PUA films with micro/nanostructures on their surfaces using plasma treatment. In general, it is widely known that the plasma treated surface increases cell attachment as well as adsorption of ECM materials such as fibronectin, collagen and gelatin. Effect of plasma treatment on PUA especially with surface of micro/nanostructures needs to be understood further for its biomedical applications. We have evaluated the modified PUA film as a culture platform using adipose derived stem cells. Then, the behavior of stem cells and the level of adsorbed protein have been analyzed.

• Journal of Biosystems Engineering
• /
• 제27권4호
• /
• pp.335-340
• /
• 2002

Recently, in Korea, round bale wrapping silage made by fresh rice straw are partially utilized. The colors of stretch film using far wrapping the fresh rice straw round bale are white, green and black. The light transmittance of green and white color stretch film was not founded the difference. However, the light transmittance of black color stretch film was largely difference of two stretch films. This study was carried out to measure qualities of fresh rice straw wrapping silage by softening processing of fresh rice straw and colors effects of wrapping stretch film. The analyzed factors were the light transmittance of stretch film, variation of the temperature in fresh rice straw round bale and qualities of the silage in crude protein, ADF, NDF, organic acid, etc. It was difficult to find in this study the colors effects of stretch film on silage qualities by the silage wrapping. But, when make fresh rice straw wrapping silage, wrapping silage fermentation effect goes well more if handle softening the fresh rice straw.

• Journal of Magnetics
• /
• 제8권1호
• /
• pp.24-31
• /
• 2003

The discoveries of antiferromagnetic coupling in Fe/Cr multilayers by Grunberg, the Giant Magneto Resistance by Fert and Grunberg and a large tunneling magnetoresistance at room temperature by Moodera have triggered enormous research on magnetic thin films and magnetoelectronic devices. Large opportunities are especially opened by the spin dependent tunneling resistance, where a strong dependence of the tunneling current on an external magnetic field can be found. We will briefly address important basic properties of these junctions like thermal, magnetic and dielectric stability and discuss scaling issues down to junction sizes below 0.01 $\mu\textrm{m}$$^2$with respect to single domain behavior, switching properties and edge coupling effects. The second part will give an overview on applications beyond the use of the tunneling elements as storage cells in MRAMs. This concerns mainly field programmable logic circuits, where we demonstrate the clocked operation of a programmed AND gate. The second 'unconventional' feature is the use as sensing elements in DNA or protein biochips, where molecules marked magnetically with commercial beads can be detected via the dipole stray field in a highly sensitive and relatively simple way.

• 폴리머
• /
• 제30권5호
• /
• pp.445-452
• /
• 2006

본 연구에서는 슈반세포와 다양한 세포 부착인자로 코팅된 고분자 표면과의 상호관계에 대해 연구하였다. 세포 접착인자로 알려진 피브로넥틴, 피브리노겐, 라미닌, 비트로넥틴, 폴리-D-라이신 및 폴리-L-라이신을 PLGA 필름에 코팅하고 물 접촉각 측정과 ESCA 분석을 실시해 표면특성을 평가하구 접착인자로 코팅하거나 하지 않은 PLGA 필름의 표면에 슈반세포를 배양한 후 세포 계수와 SEM 관찰을 통해 세포 부착과 성장을 알아보았다. 세포 계수 결과에서 세포 부착은 PLGA 표면의 단백질 흡착과 관련 있음을 확인할 수 있었으며, 세포의 성장은 배양액의 우태아혈청 함량의 영향을 받는 것으로 나타났다. 이러한 결과를 통해 슈반세포의 접착과 성장이 특정한 세포 접착인자에 의해 영향을 받음을 알 수 있었다. 본 실험의 결과를 통해 조직공학적 신경 재생에 응용하기 위한 신경유도관의 개발에서 세포의 부착과 성장을 향상시키기 위해서는 세포의 종류 및 배양조건에 따라 신경유도관이 적절한 표면환경을 제공해야 함이 필수적임을 알 수 있었다.

• Journal of Applied Biological Chemistry
• /
• 제54권3호
• /
• pp.166-170
• /
• 2011

실크 피브로인은 누에로부터 생산되는 천연단백질로서 생분해성과 생체적합성을 가지고 있어 생체재료로 사용하기에 적합한 물질이다. 본 연구에서는 이러한 실크 피브로인이 세포 생장에 미치는 영향을 확인하기 위해서, 다양한 농도의 실크 피브로인 용액을 만들고 이를 이용하여 실크 피브로인 필름을 제작하였다. 제작된 실크 필름에서 세포를 배양한 후 세포부착과 증식 능력, 형태등을 관찰하였으며, 세포 부착과 생장관련 유전자의 발현을 분석하였다. 그 결과 0.1과 1% 실크 피브로인 필름에서 배양한 세포가 세포 부착능력이 가장 우수했으며, 특히 1% 필름에서 자란 세포의 경우 다른 농도의 필름에서 보다 그 생장이 매우 좋았다. 또한 세포 생장과 관련된 유전자의 발현 수준은 0.1과 1% 실크 피브로인 필름에서 증가됨을 확인 할 수 있었다. 이러한 결과는 실크를 이용하여 다양한 용도의 의료용 소재로 사용하는데 있어 기존의 다른 생체막을 대체할 수 있을 뿐 아니라, 실크 생체막의 사용으로 결손된 부위에 대한 빠른 치유효과 또한 기대할 수 있을 것이라 생각된다.

• 한국식품영양학회지
• /
• 제21권2호
• /
• pp.165-175
• /
• 2008

Pacific saury, Cololabis saira kwamaegi, is a traditional local food of the Eastern sea area centering around Pohang. It is well-recognized as being both tasty and nutritious. Nevertheless, bacterial contamination, excessive dryness, and compositional changes have made it edible only during the winter months. Therefore, to improve its storage, this study examined the effects of storage material, type, temperature, and duration on compositional changes in kwamaegi. The studied samples were kwamaegis that had been dried naturally for 15 days. The storage materials included an A-film, a self-developed multi-film made of polyethylene, polyamide, EVOH, and polyethylene; as well as a B-film made of polyethylene, nylon, polyethylene, nylon and polyethylene. The B films were used after pressing and laminating. The storage types included one whole fish(1G), or 2 divided fish(2G), to increase eating convenience. The 2G type was the muscle portion divided vertically after discarding the jowl, skin, and internal organs. The storage temperatures were $0^{\circ}C$, $-15^{\circ}C$, and $-30^{\circ}C$, and the storage durations were 2, 4, and 6 months. Pathogenic bacteria and rheology were measured to observe general compositional changes. The whole kwamaegi showed a total cell number of $1,565{\pm}112$ CFU/100 g flesh, while the divided Kwamaegi showed significantly greater bacterial numbers at $2,031{\pm}145$ CFU/100 g flesh. Psychrophils and halophils increased significantly while coliform were not found; the number of mesophils also increased, but not significantly. There were no significant cell number variations between the A-film and B-film. At $0^{\circ}C$, both the A-and B-films resulted in cell numbers of $115{\sim}212$ CFU/100 g flesh, revealing just $7.3{\sim}10.4%$ of the initial storage levels. Overall, there were no significant differences between the storage materials. Generally, as the storage temperature and duration increased, the moisture content of the kwamaegi decreased. Also, as storage duration and temperature increased, crude protein and crude lipid contents increased; in addition, they increased proportionally as the moisture content of the fish decreased. There were no significant differences in crude ash content with respect to the storage materials, storage temperatures, or storage durations. Finally, there were no significant differences between the kwamaegi samples naturally dried for 15 days and those stored in the B-film vacuum storage for 6 months for strength, hardness, cohesiveness, springiness, gumminess, and water activity.

• Journal of Korean Neurosurgical Society
• /
• 제64권4호
• /
• pp.562-574
• /
• 2021

Objective : This study is to evaluate the efficacy and safety of demineralized bone matrix (DBM) gel versus DBM gel with recombinant human bone morphogenetic protein-2 (rhBMP-2) used in transforaminal lumbar interbody fusion (TLIF). Methods : This study was designed as a prospective, multi-center, double-blind method, randomized study. All randomized subjects underwent TLIF with DBM gel with rhBMP-2 group (40 patients) as an experimental group or DBM gel group (36 patients) as a control group. Post-operative observations were performed at 12, 24, and 48 weeks. The spinal fusion rate on computed tomography scans and X-rays films, Visual analog scale pain scores, Oswestry disability index and SF-36 quality of life (QOL) scores were used for the efficacy evaluation. The incidence rate of adverse device effects (ADEs) and serious adverse device effects (SADEs) were used for safety evaluation. Results : The spinal fusion rate at 12 weeks for the DBM gel with rhBMP-2 group was higher with 73.68% compared to 58.82% for the DBM gel group. The 24 and 48 weeks were 72.22% and 82.86% for the DBM gel with rhBMP-2 group and 78.79% and 78.13%, respectively, for the DBM gel group. However, there were no significant differences between two groups in the spinal fusion rate at 12, 24, and 48 weeks post-treatment (p=0.1817, p=0.5272, p=0.6247). There was no significant difference between the two groups in the incidence rate of ADEs (p=0.3836). For ADEs in the experimental group, 'Pyrexia' (5.00%) was the most common ADE, followed by 'Hypesthesia', 'Paresthesia', 'Transient peripheral paralysis', 'Spondylitis' and 'Insomnia' (2.50%, respectively). ADEs reported in control group included 'Pyrexia', 'Chest discomfort', 'Pain', 'Osteoarthritis', 'Nephropathy toxic', 'Neurogenic bladder', 'Liver function analyses' and 'Urticaria' (2.86%, respectively). There was no significant difference between the two groups in the incidence rate of SADEs (p=0.6594). For SADE in the experimental group, ''Pyrexia' and 'Spondylitis' were 2.50%. SADE reported in the control group included 'Chest discomfort', 'Osteoarthritis' and 'Neurogenic bladder'. All SADEs described above were resolved after medical treatment. Conclusion : This study demonstrated that the spinal fusion rates of DBM gel group and DBM gel with rhBMP-2 group were not significantly different. But, this study provides knowledge regarding the earlier postoperative effect of rhBMP-2 containing DBM gel and also supports the idea that the longer term follow-up results are essential to confirm the safety and effectiveness.