• Title/Summary/Keyword: gels

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A Comparison of Hydrated versus Dehydrated Gels for Evaluation of Apoptosis in Comet Assay Slides (Comet assay slides 에서 나타난 apoptosis 평가에서 함수 및 탈수 겔의 비교)

  • 최민철;수즌엠러루;에드워드엘질럿
    • Journal of Veterinary Clinics
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    • v.13 no.2
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    • pp.158-162
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    • 1996
  • Comet assay 는 포유류 세포에서 DNA의 파괴를 측정하는데 있어 신속하고 단순하며 시각적이고 민감한 방법이다. Apoptosis에서는 세포핵의 광범위한 DNA의 붕괴가 일어나므로 comet assay는 종양세포에서 apoptosis가 발생되었는가를 알아내는데 유용하다. 본 연구는 apoptosis 연구의 결과가 변화되지 않도록 comet assay slides를 좀 더 오래 보관할 수 있는 방법을 개발하고자 시행되었다. 개의 종양세포를 가지고 alkali comet assay를 끝낸 뒤 slides를 진공 건조기에서 꺼내서 증류수로 점적하여 10-20분간 침수시키고 현광현미경하에서 육안적으로 관찰하였다. 건조후 3-4일, 1주, 2주, 3주, 4주 및 7주의 slides에서 apoptosis 회복율(%)은 각각 98.1, 98.3, 99.4, 80.8 및 35.2%이었다. 3주 이내의 slides에서 대조군과 비교하여 apoptosis 회복율에서 차이가 없었으나 4주 이상의 slides를 건조후 침수시키는 방법을 이용하였을 때 apoptosis 평가에서 건조 후 3주간까지는 처음의 결과와 차이가 없으며, 이 방법을 이용하여 comet slide의 좀 더 긴 기간이 보관과 보관후의 재평가에서 이용될 수 있는 좋은 방법이 된다.

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Mullitization of Aluminium Silicate Gel (Aluminium Silicate Gel의 Mullite화)

  • 이광식;이형복;정윤중
    • Journal of the Korean Ceramic Society
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    • v.26 no.5
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    • pp.625-630
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    • 1989
  • Aluminium silicate gels were prepared by gel-technique using Al(OH)3 and TEOS as starting materials. Aluminium silicate gel as formed mullite at 120$0^{\circ}C$. From this method, homogeneous mullite was formed available needle-like shaped and close compacted. As excess SiO2 mullite composition, the needle-like shaped crystal, size according to increased with SiO2, was increased from 3${\mu}{\textrm}{m}$ to 7${\mu}{\textrm}{m}$ but liquid phase did not affect the formation of needle-like shaped mullite. As excess Al2O3 mullite composition, the needle-shape mullite crystal could not be detected because Al2O3 acted as chunky behavior.

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Preparation of Water-Soluble Syndiotacticity-Rich Low Molecular Weight Poly(vinyl alcohol) by Solution Copolymerization of Vinyl Pivalate/Vinyl Acetate in Tetrahydrofuran and Saponification (피발산비닐과 아세트산비닐의 테트라히드로푸란계 용액공중합에 의한 수용성 저분자량 교대배열 폴리비닐알코올의 제조)

  • Lyo, Won-Seok;Yeum, Jeong-Hyun;Ji, Byung-Chul
    • Proceedings of the Korean Fiber Society Conference
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    • 2002.04a
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    • pp.187-190
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    • 2002
  • Poly(vinyl alcohol) (PVA) is a representative hydrophilic and water-soluble polymer and widely employed in various applications such as fibers for clothes and industries, films, membranes, medicines for drug delivery system, and cancer cell-killing embolic materials. Moreover, PVA fibers, gels, and films are potentially high-performance materials because they have high tensile and impact strengths, high tensile modulus, high abrasion resistance, excellent alkali resistance, and oxygen barrier property which are superior to those of any known polymers[1,2]. (omitted)

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Recent advances in topical anesthesia

  • Lee, Hyo-Seol
    • Journal of Dental Anesthesia and Pain Medicine
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    • v.16 no.4
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    • pp.237-244
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    • 2016
  • Topical anesthetics act on the peripheral nerves and reduce the sensation of pain at the site of application. In dentistry, they are used to control local pain caused by needling, placement of orthodontic bands, the vomiting reflex, oral mucositis, and rubber-dam clamp placement. Traditional topical anesthetics contain lidocaine or benzocaine as active ingredients and are used in the form of solutions, creams, gels, and sprays. Eutectic mixtures of local anesthesia cream, a mixture of various topical anesthetics, has been reported to be more potent than other anesthetics. Recently, new products with modified ingredients and application methods have been introduced into the market. These products may be used for mild pain during periodontal treatment, such as scaling. Dentists should be aware that topical anesthetics, although rare, might induce allergic reactions or side effects as a result of an overdose. Topical anesthetics are useful aids during dental treatment, as they reduce dental phobia, especially in children, by mitigating discomfort and pain.

Preparation and Evaluation of Adhesive Hydrogel of Ketoprofen Using Microsphere System (마이크로스피어 시스템을 이용한 케토프로펜 점착성 하이드로겔의 제조 및 평가)

  • Cho, Young-Ho;Lee, Gye-Won
    • KSBB Journal
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    • v.25 no.3
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    • pp.297-302
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    • 2010
  • Ketoprofen is one of the propionic acid class of nonsteroidal anti-inflammatory drug with analgesic and antipyretic effects. The most common side effects from ketoprofen after oral administration are gastrointestinal irritation, diarrhea, abdominal pain and retention of fluid. Ketoprofen was formulated as water-soluble gels to reduce these side effects. To increase the skin permeability of ketoprofen, microsphere containing ketoprofen was prepared with chitosan and ploy-$\varepsilon$-caprolactone. And then prepared microsphere was manufactured as an adhesive hydrogel with polyvinylpyrrolidone K-25, polyethylene glycol 4000, and various permeation enhancers. The flux and permeability of ketoprofen were evaluated. As the concentration of tween 80 and enhancers increased, the flux of ketroprofen was accelerated. Also the permeation rate was facilitated by enhancers, but did not affect the lag time. From these results, the adhesive hydrogel using microsphere could be a good delivery system for ketoprofen to improve the skin permeation.

Fluidized Bed Drying Effect on the Aerogel Powder Synthesis

  • Hong, Seong-Hoon;Lee, Dong-Kyu;Oh, Chang-Sup;Kim, Yong-Ha
    • Journal of Energy Engineering
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    • v.21 no.1
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    • pp.43-46
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    • 2012
  • A fluidized bed drying approach was utilized to the synthesis of water glass based silica aerogel powders. The effects of the fluidized bed drying conditions such as the superficial velocity and temperature of hot air and bead size as well as bead/wet-gel ratio, on the physical properties such as tapping density and productivity of the aerogel powders were systematically investigated. The experimental results showed that the amount of beads mixed with wet-gels in the fluidized bed column has the most profound impact on the fluidization efficiency, greatly enhancing the yield of the aerogel powders up to 98% with a proper bead/wet-gel weight ratio as compared to 72% without using beads. No significant change was observed in the tapping density over a wide range of the fluidized drying condition. Consequently the fluidized bed drying approach shows a good promise as an alternative route for the large-scale production of the aerogel powders.

Phase Equilibria of Ethane Hydrate in Porous Silica Gels (다공성 실리카 젤에서 에탄 하이드레이트의 상평형 측정)

  • Lee, Seung-Min;Cha, In-Uk;Lee, Ju-Dong;Seo, Yong-Won
    • 한국신재생에너지학회:학술대회논문집
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    • 2008.05a
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    • pp.584-587
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    • 2008
  • 최근 새로운 천연가스 수송/저장 방법으로 가스 하이드레이트 형성법이 주목받고 있다. 본 연구에서는 천연가스의 저장 매체로 다공성 실리카 젤을 사용하였다. 다공성 매질을 사용할 경우 물이 기체와 접촉하는 면적이 극대화되어 하이드레이트로의 전환율이 높아진다. 기공의 직경이 각각 6.0, 15.0, 30.0 nm의 실리카 젤을 사용하여 270 - 285 K의 온도 범위와 0.5 - 3.0 MPa의 압력 범위에서 기공 크기의 분포를 고려하여 에탄 하이드레이트의 3상 평형점 (하이드레이트 (H) - 물 (LW) - 기상 (V))을 측정하였다. 기공의 크기가 작아질수록 벌크 상태의 에탄 하이드레이트에 비해 하이드레이트 평형 조건이 온도는 낮아지고 압력이 높아지는 저해효과가 커짐을 알 수 있었다. 천연가스 수송/저장으로의 응용을 고려할 경우 저해효과가 적은 30.0 nm 이상의 실리카 젤을 사용하는 것이 유용할 것으로 사료된다. 본 연구의 결과는 심해저 천연가스 개발, 이산화탄소 심해저장 등의 가스 하이드레이트 응용 연구에도 유용한 기초자료가 될 것이다.

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Foreign Body Granulomas after the Use of Dermal Fillers: Pathophysiology, Clinical Appearance, Histologic Features, and Treatment

  • Lee, Jeong Min;Kim, Yu Jin
    • Archives of Plastic Surgery
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    • v.42 no.2
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    • pp.232-239
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    • 2015
  • A foreign body granuloma is a non-allergic chronic inflammatory reaction that is mainly composed of multinucleated giant cells. Foreign body granulomas may occur after the administration of any dermal filler. Factors such as the volume of the injection, impurities present in the fillers, and the physical properties of fillers affect granuloma formation. The formation of granulomas involves five phases: protein adsorption, macrophage adhesion, macrophage fusion, and crosstalk. The clinical and pathologic features of granulomas vary depending on the type of filler that causes them. Foreign body granulomas can be treated effectively with intralesional corticosteroid injections. Surgical excisions of granulomas tend to be incomplete because granulomas have ill-defined borders and moreover, surgical excisions may leave scars and deformities.

Identification of Differentially Expressed Genes by cDNA-AFLP in Magnaporthe oryzae

  • Chi, Myoung-Hwan;Park, Sook-Young
    • Research in Plant Disease
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    • v.25 no.4
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    • pp.205-212
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    • 2019
  • Analysis of differentially expressed genes has assisted discovery of gene sets involved in particular biological processes. The purpose of this study was to identify genes involved in appressorium formation in the rice blast fungus Magnaporthe oryzae via analysis of cDNA-amplified fragment length polymorphisms. Amplification of appressorial and vegetative mycelial cDNAs using 28 primer combinations generated over 200 differentially expressed transcript-derived fragments (TDFs). TDFs were excised from gels, re-amplified by PCR, cloned, and sequenced. Forty-four of 52 clones analyzed corresponded to 42 genes. Quantitative real-time PCR showed that expression of 23 genes was up-regulated during appressorium formation, one of which was the MCK1 gene that had been shown to be involved in appressorium formation. This study will be providing valuable resources for identifying the genes such as pathogenicity-related genes in M. oryzae.

Antiinflammatory Activity of Ketoprofen Gel (케토프로펜 겔의 함염증작용)

  • Tan, Hyun-Kwang;Chi, Sang-Cheul;Jun, H.Won
    • Journal of Pharmaceutical Investigation
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    • v.24 no.1
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    • pp.17-24
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    • 1994
  • The antiinflammatory and antirheumatic activities of a 3% ketoprofen gel (ID-GEL) were evaluated using carrageenan-induced paw edema method and adjuvant-induced arthritis method, respectively, after its transdermal administration of 50 mg on rat paws in reference to existing transdermal preparations containing 3% ketoprofen and other nonsteroidal antiinflammatory drugs (NSAIDs). The % inhibition of carrageenan-induced edema by ID-GEL was 56.2-65.0%, close to the maximum inhibition obtainable with this model, while the % inhibition by existing 3% ketoprofen gels and other NSAID transdermal preparations were 33.8-47.7% and 18.7-29.2%, respectively. ID-GEL had a pronounced antirheumatic activity in both preventive and curative studies with adjuvant-induced arthritis in rats in respect with the inhibition of edema, arthritis score and weight gain, in reference to existing 3% ketoprofen gel.

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