• Restorative Dentistry and Endodontics
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• 제29권4호
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• pp.370-377
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• 2004

The purpose of this study was to regenerate human dental pulp tissues similar to native pulp tissues. Using the mixture of type I collagen solution, primary cells collected from the different tissues (pulp, gingiva, and skin) and NIH 3T3 ($1{\;}{\times}{\;}10^5{\;}cells/ml/well$) were cultured at 12-well plate at $37^{\circ}C$ for 14 days. Standardized photographs were taken with digital camera during 14 days and the diameter of the contracted collagen gel matrix was measured and statistically analyzed with student t-test. As one of the pulp tissue engineering, normal human dental pulp tissue and collagen gel matrix cultured with dental pulp cells for 14 days were fixed and stained with Hematoxyline & Eosin. According to this study, the results were as follows: 1. The contraction of collagen gel matrix cultured with pulp cells for 14 days was significantly higher than other fibroblasts (gingiva, skin) (p < 0.05), 2. The diameter of collagen gel matrix cultured with pulp cells was reduced to 70.4% after 7 days, and 57.1% after 14 days. 3. The collagen gel without any cells did not contract, whereas the collagen gel cultured with gingiva and skin showed mild contraction after 14 days (88.1% and 87.6% respectively). 4. The contraction of the collagen gel cultured with NIH 3T3 cells after 14 days was higher than those cultured with gingival and skin fibroblasts, but it was not statistically significant (72.1%, p > 0.05). 5. The collagen gel matrix cultured with pulp cells for 14 days showed similar shape with native pulp tissue without blood vessels. This approach may provide a means of engineering a variety of other oral tissue as well and these cell behaviors may provide information needed to establish pulp tissue engineering protocols.

• 대한의생명과학회지
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• 제7권1호
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• pp.17-25
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• 2001

This study was performed to assess the effects of exogenous collagen gel for the re-epithelialization of partial thickness skin wound healing in rabbits. Adult male rabbits (New Zealand White Rabbit) 1.5~2 kg, were used for experimental animals. Skin wounds (1.5$\times$2 cm length) were created bilaterally on the flank of 10 rabbits and then treated a periods of 9 days. Wounds on the experimental site were treated with exogenous collagen gel as well as fabric material gauze dressing. Control site wounds were covered with fabric material gauze dressing alone. Histological findings indicated that the epithelial migration of the experimental site of rabbits was far more rapid than that in the other control wound sites. Moreover, exogenous collagen gel provided a moist environment to keep wound clean, and facilitate keratinocyte proliferation. The wound dressed with exogenous collagen gel demonstrated a significant increase in the healing rate and re-epithelialization.

• Asian-Australasian Journal of Animal Sciences
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• 제16권2호
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• pp.269-276
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• 2003

We studied the gel properties of porcine collagen with microbial transglutaminase (MTGase) as a catalyst. A creep meter was used to measure the mechanical properties of gel. The results showed samples with high concentration of MTGase gelled faster than those with a low concentration of MTGase. The gel strength increased with incubation time and the peaks of breaking strength for 0.1, 0.2 and 0.5% MTGase were obtained at 40, 20 and 10 min incubation time, respectively. According to SDS-PAGE, the MTGase was successfully created a collagen polymer with an increase in molecular weight, whereas no change in formation was shown without MTGase. The sample with 0.5% MTGase began to polymerize after 10 or 20 min incubation at $50^{\circ}C$, and complete polymerization occurred after 40-60 min incubation. Scanning electron microscopic analysis revealed that the gel of porcine collagen in the presence of MTGase produced an extremely well cross-linked network. The differential scanning calorimetric analysis showed the peak thermal transition of porcine collagen gel was at $36^{\circ}C$, and that with MTGase no peak was detected during heating from 20 to $120^{\circ}C$. The melting point of porcine collagen gel could be controlled by MTGase concentration, incubation temperature and protein concentration. Knowledge of the structural and physicochemical properties of porcine collagen gel catalyzed with MTGase could facilitate their use in food products.

• Journal of Microbiology and Biotechnology
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• 제7권4호
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• pp.267-271
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• 1997

We developed a dermal equivalent (DE) which was engineered using human dermal fibroblasts and a matrix of collagen gel. The in vitro construction of the DE was accomplished by casting a porcine collagen type I solution plus concentrated medium with isolated and cultured fibroblasts. These constructs were attached to culture dishes or left floating in culture medium. Contraction of attached gels results in decreased gel thickness without a change in gel diameter, and contraction of floating gels results in decreased gel thickness and diameter. After contraction, there was no increase in cell number in floating gels, but cells in attached gels began to increase after about 4 days of the lag phase in cell growth curve. At this lag phase, addition of fibroblast growth factor (FGF) at a concentration of $0.1{\mu}$/ml promoted cell proliferation in the attached collagen gels, but no effect in floating gels. These results indicate that the method of contraction had an influence on the extracellular matrix (ECM) organization, and this influenced not only cell growth but also fibroblast responsiveness to FGF. This suggests that attached collagen gel is more suitable as a dermal equivalent than the floating gel. And the final contracted area of attached gel is much larger than that of the floating gel since floating gel is contracted in all directions but attached gel is contracted only vertically.

• KSBB Journal
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• 제11권4호
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• pp.453-461
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• 1996

간세포를 in vitro에서 효율적으로 장기간 배양 및 증식을 유도하여 이용하는 기술을 수립하기 위해서 본 연구에서는 일차배양한 쥐 간세포에 중요한 세포외 기질(ECM)인 collagen이 간세포의 장기배양시 생존능과 기능유지에 미치는 영향을 분석하고자 하였다. 간세포를 in vitrovo에서 40여일 간의 장기간 배양시에 일반적으로 사용되고 있는 단층 배양(single gel)법과 in vivo 상태의 세포 극성에 유사한 환경을 제공하는 복층 배양(sandwich gel)법으로 배양한 경우에 미치는 영향을 서로 비교하여 보았다. 이를 위해서 간세포의 생존 상태를 비교하였요며 나아가 간세포의 특성인 알부민, 파이브로넥틴, 피브리노겐 등의 단백질 생산 빛 분비기능 측정 그리고 요소 생산능과 암모니아 제거능 등을 비교하였다. 복층 배양법이 단층 배양법보다 알부민, 파이브로넥틴, 피브 리노겐 등의 분비기능을 훨씬 효율적으로 유지시키는 것을 관찰할 수 있었으며 또한 요소 생산능과 암모니아 제거능도 훨씬 더 효율적으로 장기간 유지시 킬 수 있음을 확인할 수 있었다. 이로써 in vitro에서 간세포의 기능을 효율척으로 유지시키기 위해서 간세포 배양시 3차원적 공간을 유지시키는 것이 중 요한 요인 중의 하나임을 확인할 수 있었다.

• 대한의용생체공학회:의공학회지
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• 제14권1호
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• pp.51-62
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• 1993

An experimental study was performed for the preparation of living skin-equivalent by the using collagen gel contraction with human fibroblasts as neodermls and cultured human keratinocytes as neoderm is . The results were as follows ; 1) The rate of collagen gel contraction was dependent on the number of fibroblasts into the lattice and collagen contraction was progressed according to the increment of the number of the cells. 2) The rate of collagen gel contraction was progressed according to the decrement of the contraction of the collagen. 3) The rate of gel contraction was progressed according to the increment of serum concentration in the fixed concentration of the fibroblasts and collagen. 4) The lattice contraction was decreased according to the increment of the population doublings of the fibroblasts. 5) Macroscopically, the artificial dermis was gray white in color and tissue-like consistency and elas- ticity. 6) Microscopically, three dimensionally contracted artificial dermis showed more dense fibroblasts and its newly formed collagen fibrils in the matrix than one dimensionally contracted one. 7) Finally prepared skin-equivalent showed good attachment of living stratified keratinocytes to the dermal equivalent microscopically. It has been proposed that newly formed skin-equivalent is suitable for the graft of extensively and deeply burned patients. Shortening of the manufacturing period of skin-equivalent and development of conservation technique as a readily usable state are to be solved for our ongoing works.

• 대한의생명과학회지
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• 제15권3호
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• pp.241-247
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• 2009

Wound healing is a complex and highly organized biological response to injury that results in the loss of tissue integrity. Our particular interest was propolis, traditional used as an antimicrobial and an anti-inflammatory agent. The purpose of this study was to see the effects of propolis on healing of the laser induced wounds and the level of collagen formation. 808 nm laser (20 J) was irradiated on the back of rats. Irradiated wounds were divided into gel control and 6 experimental groups (3 and 5% of different three kinds of propolis). Gel type of propolis (supplied by Seoul Propolis Co., Daejeon, Korea) in water based were applied on the laser wound once daily for 14 days. One fourth of rats were sacrificed on $3^{rd}$, $7^{th}$, $10^{th}$, and $14^{th}$ day and each wound was evaluated for degree of wound healing and the level of collagen formation. Healing of wound was evaluated by measuring and comparing the width and depth of the wounds. The levels of collagen were increased in 3 and 5% gel groups comparing to control on $3^{rd}$ day and the collagen level were increased more on $7^{th}$ day. Wounds of the experimental groups showed better healing in width comparing to the healing of the control. The results of this study demonstrated that propolis accelerated healing of wounds induced by laser irradiation and good collagen formation.

• 폴리머
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• 제36권6호
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• pp.789-794
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• 2012

생체적합성 및 생분해성의 장점을 지닌 PLGA는 우수한 기계적 성질과 분해속도를 조절할 수 있는 장점을 가지고 있지만 소수성으로 인해 세포의 초기부착률이 낮고, 지지체 내부에 영양액의 공급이 원활하지 않다. 본 연구에서는 이러한 단점을 보완하고자 탈미네랄화된 골분(DBP, demineralized bone particle) 젤을 PLGA 지지체에 함침시켰다. 다양한 형태의 지지체 압축강도를 측정한 결과 PLGA/DBP 지지체가 연골과 비슷한 강도를 가지고 있었으며, 이를 바탕으로 DBP젤을 함침시킨 PLGA/DBP젤 지지체를 제작하였다. 연골세포를 파종하여 in vivo 실험을 진행하였고 조직화 정도를 확인하기 위해 H&E, Safranin-O, Alcian blue, Collagen type I 및 Collagen type II 염색을 실시하였다. 그 결과 DBP를 함침시킨 PLGA 지지체에서 GAG, Collagen type I 및 Collagen type II의 높은 발현과 조직화를 보여 연골조직으로 대체할 수 있는 가능성을 확인하였다.

• Mass Spectrometry Letters
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• 제12권3호
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• pp.81-84
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• 2021

Collagen, which accounts for one-third of human protein, is reduced due to human aging, and much attention is focused on making collagen into food to prevent such aging. Gel permeation chromatography with Reflective Index (RI) detection (GPC/RI) was chosen as the most suitable instrument to confirm molecular weight distribution, and we explored the use of this technique for analysis of collagen peptide molecular sizes and distributions. Data reliability was verified by matrix-assisted laser desorption/ionization coupled to time-of-flight (MALDI-TOF) mass spectrometric analysis. The data were considered meaningful for comparative analysis of molecular weight distribution patterns.

• Journal of Periodontal and Implant Science
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• 제40권6호
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• pp.257-264
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• 2010

Purpose: Connective tissue reattachment to periodontally damaged root surfaces is one of the most important goals of periodontal therapy. The aim of this study was to develop a root conditioning agent that can demineralize and detoxify the infected root surface. Methods: Dentin slices obtained from human teeth were treated with a novel root planing agent for 2 minutes and then washed with phosphate-buffered saline. Smear layer removal and type I collagen exposure were observed by scanning electron microscopy (SEM) and type I collagen immunostaining, respectively. Cell attachment and lipopolysaccharides (LPS) removal demonstrated the efficiency of the root conditioning agent. Results: SEM revealed that the smear layer was entirely removed and the dentinal tubules were opened by the experimental gel. Type I collagen was exposed on the surfaces of the dentin slices treated by the experimental gel, which were compared with dentin treated with other root planing agents. Dentin slices treated with the experimental gel showed the highest number of attached fibroblasts and flattened cell morphology. The agar diffusion assay demonstrated that the experimental gel also has effective antimicrobial activity. Escherichia coli LPS were effectively removed from well plates by the experimental gel. Conclusions: These results demonstrated that this experimental gel is a useful tool for root conditioning of infected root surfaces and can also be applied for detoxification of ailing implant surface threads.