• Archives of Plastic Surgery
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• 제35권6호
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• pp.716-722
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• 2008

Purpose: Split or full thickness skin graft is generally used to reconstruct the palmar skin and soft tissue defect after release of burn scar flexion contracture of hand. As a way to overcome and improve aesthetic and functional problems, the authors used the preserved superficial fat skin(PSFS) composite graft for correction of burn scar contracture of hand. Methods: From December of 2001 to July of 2007, thirty patients with burn scar contracture of hand were corrected. The palmar skin and soft tissue defect after release of burn scar contracture was reconstructed with the PSFS composite graft harvested from medial foot or below lateral and medial malleolus, with a preserved superficial fat layer. To promote take of the PSFS composite graft, a foam and polyurethane film dressing was used to maintain the moisture environment and Kirschner wire was inserted for immobilization. Before and after the surgery, a range of motion was measured by graduator. Using a chromameter, skin color difference between the PSFS composite graft and surrounding normal skin was measured and compared with full thickness skin graft from groin. Results: In all cases, the PSFS composite graft was well taken without necrosis, although the graft was as big as $330mm^2$(mean $150mm^2$). Contracture of hand was completely corrected without recurrence. The PSFS composite graft showed more correlations and harmonies with surrounding normal skin and less pigmentation than full thickness skin graft. Donor site scar was also obscure. Conclusion: The PSFS composite graft should be considered as a useful option for correction of burn scar flexion contracture of hand.

• 한국수소및신에너지학회논문집
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• 제15권3호
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• pp.201-207
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• 2004

Redox characteristics of metal oxide for hydrogen production by thermochemical water-splitting were investigated. $CuFe_2O_4$ as a redox pair that had a different molar ratio of Cu and Fe were prepared by co-precipitation method. Hydrogen production consisted of water-splitting step and thermal reduction step was performed below 1200K. Redox characteristics of Cu-ferrites were studied using the thermal gravimetric analysis technique. Also, structure change of Cu-ferrite during thermal reduction was investigated using the high temperature controlled XRD. In results, oxygen release of Cu-ferrite during the thermal reduction was initiated at oxygen site combined with Cu. Consequently, oxygen release amount of Cu-ferrite was increased with increase of Cu molar ratio of Cu-ferrite. It was found that thermal reduction of Cu-ferrite was begun at $875^\circ{C}$. It was confirmed that structure of Cu-ferrite was changed to metal and cation excess metal oxide during the thermal reduction step.

• Journal of Radiation Protection and Research
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• 제12권1호
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• pp.40-47
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• 1987

우리나라에 현재 건설중인 원자력발전소 9/10호기와 동일형인 프랑스형 900 MWe PWR 에 대해 프랑스에서 TMI 사고이후 선원항을 보수적으로 설정한 RFS V.1.a의 가정에 따라 LOCA시의 핵분열생성물질방출분석과 그에 대한 파급효과를 평가 해석하였다. 방사능 환경방출에 의한 영향평가결과 주거제한구역경계 (500 m)에서 전신외부피폭선량은 사고발생후 2시간 경과시 0.66 rem이며 방사성 옥소의 방출에 의한 갑상선 피폭선량도 동일한 시간에서 유기성 옥소의 누출율이 l0%일때 13.5 rem 으로 사고시 피폭선량 제한치이하임이 나타났다. 그러나 격납용기외부로 누출되는 방사성 옥소중 유기성 옥소의 누출율이 갑상선의 방사선피폭에서 중요한 역활을 하고있음이 나타났으며 그 누출율이 10%이상이 될 경우 주거제한구역경계에서 사고시 갑상선 피폭선량제한치를 초과할 수도 있다는 가능성을 보여주고 있다.

• 한국해안해양공학회지
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• 제10권3호
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• pp.132-140
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• 1998

진해·마산만은 오염부하량의 측정자료가 미흡하기 때문에 오염부하량에 대한 정량적인 분석·평가연구가 수행될 수 없었을 뿐만 아니라, 연안의 수질변화를 예측하는 수질모형의 다각적인 보정·검증작업이 제한적으로 이루어 질 수 밖에 없었다. 본 연구에서는 진해·마산만 22개 하천과 해양방류관을 통한 오염부하량을 측정하고, 해역내 3개 지점에서 오염물질 용출률을 측정하였다. 마산·창원 유역의 오염부하량은 진해·마산만 전체 오염부하량의 80∼90% 정도를 차지하고 있으며, 해양방류관에 의한 오염부하량은 20∼25%를 차지한다. 또한, 퇴적물로부터의 오염부하량이 유역 오염부하량과 대등하기 때문에, 퇴적물로부터 용출되는 오염물질량은 하계 수질악화 및 동계 수질양호의 계절적인 변화를 결정하는 주요한 인자 중의 하나로 파악되었다.

• 한국유기농업학회지
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• 제7권2호
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• pp.125-151
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• 1999

After the release of facts that the high nitrate contents in vegetables by Korean organic farming, organic farmers were recommended by Korean Organic Farmer Association to apply 20t/ha compost while they applied before as much as they could, sometimes even more than 100t/ha. This study was aimed to check the safety of Korean organic product in terms of nitrate content. Current nitrate content in leaf and root vegetables by 3 different farming systems(organic farming, conventional farming, greenhouse farming) were monitored and furthermore it was compared with previously published another data in Korea to find out any changes among the monitored years(1993-1999). Current nitrate content in chinese cabbage, lettuce and kale became less compare to those of the beginning of monitoring, and especially those cultivated organic farming got the lowest value while previous organic vegetables at beginning of 90's showed the higher value than those cultivated in greenhouse. This decrease in organic vegetables was affected by less application rate of organic fertilizer than before at 20t/ha. But the nitrate level by organic farming was still higher compare to those cultivated by conventional farming in open field, since currently monitored organic vegetables were cultivated basically in greenhouse condition. It shows the organic farmer the necessity of transfer their farming site and condition from greenhouse to open field in order to decrease of its high level of nitrate caused long-term application and slow release characteristics of organic fertilizer. It was concluded the adoption of soil nitrate test to recommend a organic farmer the exact application rate for need of crop growth. Additionally the mechanism of lower nitrate accumulation in rice and fruit vegetables were also discussed in the paper.

• Asian-Australasian Journal of Animal Sciences
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• 제32권7호
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• pp.977-987
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• 2019

Objective: The use of tannin extract and other phytochemicals as dietary additives in ruminants is becoming more popular due to their wide biological actions such as in methane mitigation, bypass of dietary protein, intestinal nematode control, among other uses. Unfortunately, some have strong astringency, low stability and bioavailability, and negatively affecting dry matter intake and digestibility. To circumvent these drawbacks, an effective delivery system may offer a promising approach to administer these extracts to the site where they are required. The objectives of this study were to encapsulate acacia tannin extract (ATE) with native starch and maltodextrin-gum arabic and to test the effect of encapsulation parameters on encapsulation efficiency, yield and morphology of the microparticles obtained as well as the effect on rumen in vitro gas production. Methods: The ATE was encapsulated with the wall materials, and the morphological features of freeze-dried microparticles were evaluated by scanning electron microscopy. The in vitro release pattern of microparticles in acetate buffer, simulating the rumen, and its effect on in vitro gas production was evaluated. Results: The morphological features revealed that maltodextrin/gum-arabic microparticles were irregular shaped, glossy and smaller, compared with those encapsulated with native starch, which were bigger, and more homogenous. Maltodextrin-gum arabic could be used up to 30% loading concentration compared with starch, which could not hold the core material beyond 15% loading capacity. Encapsulation efficiency ranged from $27.7%{\pm}6.4%$ to $48.8%{\pm}5.5%$ in starch and $56.1%{\pm}4.9%$ to $64.8%{\pm}2.8%$ in maltodextrin-gum arabic microparticles. Only a slight reduction in methane emission was recorded in encapsulated microparticles when compared with the samples containing only wall materials. Conclusion: Both encapsulated products exhibited the burst release pattern under the pH conditions and methane reduction associated with tannin was marginal. This is attributable to small loading percentages and therefore, other wall materials or encapsulation methods should be investigated.

• The Korean Journal of Physiology and Pharmacology
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• 제25권4호
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• pp.333-339
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• 2021

Injection lipolysis or mesotherapy gained popularity for local fat dissolve as an alternative to surgical liposuction. Phosphatidylcholine (PPC) and aminophyl-line (AMPL) are commonly used compounds for mesotherapy, but their efficacy and safety as lipolytic agents have been controversial. Glycerophosphocholine (GPC) is a choline precursor structurally similar to PPC, and thus introduced in aesthetics as an alternative for PPC. This study aimed to evaluate the effects of GPC on adipocytes differentiation and lipolysis and compared those effects with PPC and AMPL using in vitro and in vivo models. Adipogenesis in 3T3-L1 was measured by Oil Red O staining. Lipolysis was assessed by measuring the amount of glycerol released in the culture media. To evaluate the lipolytic activity of GPC on a physiological condition, GPC was subcutaneously injected to one side of inguinal fat pads for 3 days. Lipolytic activity of GPC was assessed by hematoxylin and eosin staining in adipose tissue. GPC significantly suppressed adipocyte differentiation of 3T3-L1 in a concentration-dependent manner (22.3% inhibition at 4 mM of GPC compared to control). Moreover, when lipolysis was assessed by glycerol release in 3T3-L1 adipocytes, 6 mM of GPC stimulated glycerol release by two-fold over control. Subcutaneous injection of GPC into the inguinal fat pad of mice significantly reduced the mass of fat pad and the size of adipocytes of injected site, and these effects of GPC were more prominent over PPC and AMPL. Taken together, these results suggest that GPC is the potential therapeutic agent as a local fat reducer.

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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• pp.501-519
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• 2003

Silk Sericin(SS) is a natural protein extracted from cocoon of bombix mori and shows moisturizing effect to the skin due to a number of hydroxyl groups in the structure. But its application to cosmetics is limited due to its poor solubility in water. In order to solve this drawback and expand its application to cosmetics, polyethyleneglycol(PEG) was conjugated with sericin by reacting activated polyethyleneglycol(ActPEG). Reaction site of sericin is tyrosine residue, which was determined by using $^1$H-NMR. Random coil structure of sericin was transformed to beta-sheet structure by conjugating polyethyleneglycol. It was confirmed that melting point of sericin-PEG conjugate was lowered compared to that of each sericin and PEG due to the interaction between sericin and PEG in crystalline structure. Self-assembled sericin-PEG nanoparticle was obtained by dialyzing with alcohol solution of sericin-PEG conjugate against water. The particle is spherical and has 200-400nm of size. The moisturizing ability of sericin-PEG nanoparticle was much higher than that of sericin itself. Incorporation of vitamin A into sericin-PEG nanoparticle was carried out by diafiltration method. The content of incorporated Vitamin A in sericin-PEG nanoparticle was 8.9 wt％. Releasing behaviour of vitamin A incorporated into nanoparticle was tested in phosphate buffer, pH 7.4 at 37$^{\circ}C$. and half-life of Vitamin A release was 43hrs. Sericin-PEG nanoparticle exhibited higher moisturing effect than sericin itself and distilled water, respectively. No toxicity and irritation were observed in animal tests. It can be expected that the self-assembled sericin-PEG nanoparticle can be developed for cosmetics.

• BMB Reports
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• 제57권2호
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• pp.71-78
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• 2024

Melanoma is one of the most aggressive skin tumors, and conventional treatment modalities are not effective in treating advanced melanoma. Although immunotherapy is an effective treatment for melanoma, it has disadvantages, such as a poor response rate and serious systemic immune-related toxic side effects. The main solution to this problem is the use of biological materials such as hydrogels to reduce these side effects and amplify the immune killing effect against tumor cells. Hydrogels have great advantages as local slow-release drug carriers, including the ability to deliver antitumor drugs directly to the tumor site, enhance the local drug concentration in tumor tissue, reduce systemic drug distribution and exhibit good degradability. Despite these advantages, there has been limited research on the application of hydrogels in melanoma treatment. Therefore, this article provides a comprehensive review of the potential application of hydrogels in melanoma immunotherapy. Hydrogels can serve as carriers for sustained drug delivery, enabling the targeted and localized delivery of drugs with minimal systemic side effects. This approach has the potential to improve the efficacy of immunotherapy for melanoma. Thus, the use of hydrogels as drug delivery vehicles for melanoma immunotherapy has great potential and warrants further exploration.

• 생태와환경
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• 제45권4호
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• pp.482-489
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• 2012

어류는 수체 내에 서식하기 때문에 시각적으로 행동이나 이동을 연구하는 데에는 어려움이 있다. 원격측정방식 중 하나인 수중음향측정 방식(acoustic telemetry)은 수생 생물 특히, 어류에 효과적으로 적용되는 방식으로 이동경로 및 거리, 패턴의 분석에 효과적이다. 본 연구에서는 국내에 서식하는 잉어과 어류인 눈불개를 대상으로 하여 수중음향측정방식을 적용, 서식처범위(home range)와 이동패턴에 대한 모니터링을 시행하였다. 연구는 금강 하구둑부터 백제보까지의 약 70 km 구간을 대상으로 총 9 개체의 눈불개를 하구둑(Sc1-3)과 백제보(Sc4-9)에서 각각 방류하여 모니터링을 진행하였다. 하구둑에서 방류한 개체들은 방류지점으로부터 12.7 km 상류지점까지를 서식처 범위로 하여 이동하는 패턴을 나타냈고, 백제보에서 방류한 개체들은 가장 하류까지 이동한 Sc6 (방류지점에서 직선거리로 53.4 km 하류까지 이동)을 제외하고 대부분 방류지점에서 7.2 km 하류 지역을 서식처 범위로 이용하고 있었다. 상대적으로 크기가 작은 Sc7, 8, 9 개체는 큰 이동을 보이지 않았다. 눈불개의 총 이동거리는 개체의 체장의 크기와 관련이 있는 것으로 나타났고($r_s$=0.715, p=0.03), 또한 이동 개체와 이동하지 않은 개체 비교 시 이동 개체들의 체장이 통계적으로 유의하게 큰 것으로 확인되었다(Mann-Whitney U test, p=0.024). 따라서 눈불개의 이동 범위는 크기와 관련이 있고, 체장이 커질수록 총 이동거리가 늘어나는 것으로 나타났다. 비록 모니터링 개체수가 많지 않았지만 대상종의 이동과 관련된 의미 있는 자료들의 수집이 가능하였으며, 연구방식이 전반적으로 국내의 다양한 어류에 안정적으로 적용이 가능하기 때문에 향후 어류의 이동을 모니터링을 하는데 있어서 활용가치가 높을 것으로 판단되었다.