• Title/Summary/Keyword: membrane penetration

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Healing of the bone around pure titanium implants without primary bone contact (초기 골 접촉이 없는 순수 티타늄 임프란트 주위 골의 치유반응)

  • Ahn, Jae-Hyun;Kim, Heung-Joong;Park, Joo-Cheol;Han, Kyung-Yoon;Kim, Byung-Ock
    • Journal of Periodontal and Implant Science
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    • v.29 no.1
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    • pp.233-249
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    • 1999
  • Primary fixation is one of the most important factor in establishing adequate osseointegration between implant and bone. To evaluate the initial healing response of bone around implants without primary bone contact, this study was designed to create considerable space between implant and bone in 5 mongrel dogs, about 1-year old. After 3 holes of 6.0mm in diameter were prepared at the femur neck of the dogs, commercially pure titanium thread type implants(STERI-$OSS^{(R)}$), 8mm in length and 3.8mm, 5.0mm and 6.0mm in diameter, were inserted. Implants were supported by only nonresorbable membrane($Teflon^{(R)}$), and the penetration of upper soft tissue into the gap was inhibited by it. The each implant was positioned in the center of the drilled hole. 9 implants with different diameters were inserted in 3 dogs for histologic observation, and 12 were inserted in 2 dogs for mobility test and removal torque test.Fluorescent dyes were injected in order of Doxycycline, Alizarin Red S, and Calcein at intervals of 2 weeks. At 4-, 8-, and 12-week after placement, 3 dogs were sacrificed for histologic observation, and at 8- and 12-week after placement, 2 dogs were sacrificed for mobility test using $Periotest^{(R)}$ (Simens AG, Bensheim, Germany) and torque test using Autograph AGS-1000D $series^{(R)}$(Japan). The result were as follows: 1. The wider the gap between bone and implant was, the less bone maturity was, and the later osseointegration was occurred. Trabecular direction of new bone around implant was changed from parallel to perpendicular to the implant, and the gap was filled with new bone, over time. 2. There was a decreasing tendency over time in the mobility of all implants, but the wider gap between bone and implant was, the smaller decrease of the mobility was. 3. There was a increasing tendency over time in the removal torque gauge of all implants, and the wider gap was, the smaller increase of the removal torque gauge was. The results suggest that osseointegration in case of implant without primary bone contact may be obtained by guided bone regeneration technique with prolonged healing period, but the time of second surgery should be considered carefully.

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Variation of Soil Properties by Permeating Injection of Chemical Grouts (약액(藥液)의 침투주입(浸透注入)에 의한 토질성상변화(土質性狀變化))

  • Chun, Byung Sik
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.2 no.4
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    • pp.1-9
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    • 1982
  • Variation of soil properties is studied by permeating injection of chemical grouts, such as cement type, water-glass type and acrylamide type, to the same soil samples with different densities. Moreover, injection tests using specially prepared equipments of 1.0 shot system and 1. 5 shot system are attempted to investigate permeating injection effects in highly compacted soil and in the presence of ground water. The main factor which causes the improvement of cut-off effect and shearing strength is the cohesion of soil. The strength in the loose state is fundamentally governed by the membrane cohesion, meanwhile, in the loose state is governed by the structural cohesion. Injection effects under the ground water flow is considerably decreased, and effective gelling ratio of approximate 45~80% is observed by variation of velocity and gel time, besides grading of injection materials has high relation with permeation and traveling length but has little relation with effective gelling ratio. Permeating injection effects, such as gelling scope, gelling strength in highly compaoted soil conditions can be confirmed by penetration resistance diagram and iso-strength curve.

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Clinical and molecular biological aspect of the hyaluronidases: basis and clinical overview for oriental medical application

  • Kim, Cheorl-Ho;Lee, Dong-Gyu;Jang, Jun-Hyouk;Kim, Jong-De;Nam, Kyung-Soo;Kim, Jeong-Joong;Park, Jong-Kun;Choo, Young-Kug;Kim, Hyung-Min;Lee, Young-Choon
    • Advances in Traditional Medicine
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    • v.1 no.1
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    • pp.8-27
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    • 2000
  • Components of extracellular matrix and the matrix-degrading enzymes are some of the key regulators of tumor metastasis and angiogenesis. Hyaluronic acid (HA), a matrix glycosaminoglycan, is known to promote tumor adhesion and migration, and its small fragments are angiogenic. Until now, we have compared levels of hyaluronidase, an enzyme that degrade HA, in normal adult prostate, benign prostate hyperplasia and prostate cancer tissues and in conditioned media from epithelial explant cultures, using a substrate (HA)-gel assay and ELISA-like assay (Kim et al., unpublished results). The present review described an overall characterization of hyaluronidases and its application to human diseases. The hyaluronidases are a family of enzymes that have, until recently, deed thorough explication. The substrate for these enzymes, hyaluronan, is becoming increasingly important, recognized now as a major participant in basic processes such as cell motility, wound healing, embryogenesis, and implicated in cancer progression. And in those lower life forms that torment human beings, hyaluronidase is associated with mechanisms of entry and spread, e.g. as a virulence factor for bacteria, for tissue dissection in gas gangrene, as a means of treponema spread in syphilis, and for penetration of skin and gut by nematode parasites. Hyaluronidase also comprises a component of the venom of a wide variety of organisms, including bees, wasps, hornets, spiders, scorpions, sh, snakes and lizards. Of particular interest is the homology between some of these venom hyaluronidases and the enzyme found in the plasma membrane of mammalian spermatozoa, attesting to the ancient nature of the conserved sequence, a 36% identity in a 300 amino acid stretch of the enzyme protein. Clearly, hyaluronidase is of biological interest, being involved in the pathophysiology of so many important' human disorders. Greater effort should be made in studying this family of enzymes that have, until recently, been overlooked. Also, oriental medical application of the hyaluronidase will be discussed with respect to inhibition and suppression of inflammation and malignacy.

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Effects of inorganic fluosilicate agent on the properties of concrete (규불화염계 혼화제가 콘크리트의 물성에 미치는 영향)

  • Lee, Sang-Ho;Moon, Han-Young
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.9 no.3
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    • pp.187-194
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    • 2005
  • This paper deals with a waterproof and mechanical feature of concrete using an inorganic self waterproof agent. The waterproof agents having been used in our country were a membrane agent, penetration agent and an organic waterproof agent. However, these agents have a lot of problems such as losing the effect of waterproof in the environment of lots of water, the difficulty of dispersion. For the clear of problems of these water -proof agents, we used the inorganic waterproof agent. This agent was made from inorganic fluosilicate. Generally, a waterproof agent has been used only for the waterproof effect. In this paper, however through the some tests of concrete using the inorganic self waterproof agent, we recognized that the concrete using the agent is more excellent in some peculiar properties than general concrete's properties. In this paper, we performed compressive strength, permeability, pore volume test, etc. As a result, the concrete of using the agent is more excellent in economy, waterproof, compressive strength.

A Study of the Transdermal Permeation of Lotion Formulations Containing Angelica gigas Nakai Extracts in Franz Diffusion Cells (Franz diffusion cell을 이용한 참당귀 추출물 함유한 로션제형의 피부 투과 연구)

  • Kim, Kang Min
    • Journal of Life Science
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    • v.31 no.11
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    • pp.1004-1009
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    • 2021
  • Angelica gigas Nakai (AGN) has been used in Korean herbal medicine for various pharmacological activities, such as to create antioxidant and skin whitening effects. Decursin and decursinol angelate of AGN extracts can be used as potential active drugs and cosmetic ingredients. This study investigated the possibility of topical delivery of AGN extracts using a manufactured emulsion system. Lotion was formulated by using Tefose® and paraffin for the oil phase, Kolliphor RH 40 for the surfactant and solubilizing agent-which showed high solubility in water (0.82 mg/ml)-and a water phase with a carbomer. In vitro skin permeation of decursin and decursinol angelate was determined using a Strat-M® membrane in Franz diffusion cells. Lotion samples as the experimental group (248.08±19.72 ug/cm2) significantly increased the permeation of decursin and decursinol angelate for up to 24 hr compared to the control group (119.18±19.23 ug/cm2). The permeability was also characterized by the flux (penetration rates) and Kp (permeability coefficient) values. The experimental group (17.20±1.23 ug/h/cm2 and 5.73±1.39 cm/h*10-3) had higher flux and Kp than the control group (8.22±1.24 ug/h/cm2 and 2.74±0.51 cm/h*10-3). Lotion with decursin and decursinol angelate of AGN extracts could be used for the topical application of drug and cosmetic products.

Physicochemical Characteristics and Skin Absorption of Transfersomes Containing Centella asiatica Extract According to Edge Activators (Edge Activator 에 따른 병풀추출물 함유 트렌스퍼좀의 물리화학적 특성과 피부흡수)

  • Eun-hee Lee;Kyung-Sup Yoon
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.49 no.2
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    • pp.147-157
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    • 2023
  • Centella asiatica extract is widely used as a raw material for cosmetics due to its various effects, but it is difficult to expect penetration into the skin due to its high molecular weight and low solubility. In order to solve these problems, lipid-based liposomes of various types were developed to increase skin absorption. Therefore, in this study, we tried to increase the skin absorption rate by preparing transfersomes using surfactants as edge activators in existing liposomes. Liposome and transfersomes containing Span 80 and Tween 20, 60, 80, and 85, respectively, were prepared using a high-pressure homogenizer, and we evaluated the particle size, polydispersity index, zeta potential, and skin absorption rate. As a result, there was almost no change in the physical properties of particle size, polydispersity index and zeta potential from 25 ℃ to 60 d, and the particle size of transfersomes containing Tween 20, 60, and 80 increased after 60 d at 45 ℃. Madecassoside, main substances of the Centella asiatica extract was used as an standard and madecassoside was measured and calculated when measuring the skin absorption rate using Franz diffusion cells. As a result, formulations containing Tween 20 were the most, whereas formulations containing Span 80 were the least. According to the skin absorption coefficient (Kp) value, all formulations showed 'very fast', and the absorption rate was similar or greater than that of liposomes, except for formulations containing Span 80. Through this, it was confirmed that the larger the HLB value of the nonionic surfactant, the smaller the particle size of the transfersome, and the increased skin absorption rate due to the increased flexibility of the vesicle membrane. Through this study, transfersome using surfactant as an edge activator can be expected to solve local skin problems not only as a cosmetic raw material or product, but also by increasing skin absorption.