• Title/Summary/Keyword: Adhesive Membrane

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Ultrastructure of the Fertilized Egg Envelope from Hyphessobrycon serpae, Characidae, Teleost (경골어류 카라신과 Hyphessobrycon serpae의 수정란 난막 미세구조)

  • Kim, Dong-Heui;Deung, Young-Kun;Lee, Kyu-Jae
    • Applied Microscopy
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    • v.35 no.2
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    • pp.89-96
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    • 2005
  • The ultrastructures of the fertilized egg envelope from Hyphessobrycon serpae belonging to Characidae was studied using scanning and transmission electron microscopes to get systematic fundamental data for classification of species and to confirm whether micropyle is a common trait of Characidae or not. The fertilized egg was of colorless, transparent, spherical, adhesive and demersal type. There were not oil droplets in vitelline membrane and attached structures in the outside of fertilize egg envelope. The egg envelope had a single micropyle resembling the pathway of sperm in the area of the animal pole. The micropyle was surrounded by 13 to 15 protruded lines of the egg envelope in a radiated form. The outer surface of fertilized egg envelope was covered by reticular adhesive fibrous structures and irregularly arranged by pore canals. The fertilized egg envelope consisted of three distinct layers an outer adhesive fibrous layer with high electron density, a middle layer with pore canals, and an inner layer consisting of 6 to 7 lamellae alternating layers with interlamellae of lower electron density. These ultrastructural characters of fertilized egg envelope form Hyphessobrycon serpae can be utilized in taxonomy of teleost, and as fundamental data for study on early development of fertilized egg. It seems that the morphology of micropyle is a common trait of Characidae

A Study on the Oogeneis of False Dace (Pseudorasbora parva) (참붕어 (Pseudorasbora parva)의 난자형성과정에 관한 연구)

  • Kim, Dong-Heui;Lee, Kyu-Jae;Kim, Seok;Deung, Young-Kun
    • Applied Microscopy
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    • v.37 no.2
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    • pp.65-72
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    • 2007
  • The oogenesis and ultrastructure of fertilized egg envelope of false dace were investigated by light and electron microscope. The cytoplasm of false dace oogonia was basophilic and many nucleoli were located at inner side of nuclear membrane. In primary oocytes, yolk vesicles were distributed in marginal area only and egg envelope was not formed on egg outside. In secondary oocyte, the egg envelope was formed and yolk vesicles were increased than that of early stage in cytoplasm. The amount of basophilic substance was decreased. In case of matured egg, thickness of egg envelope and site of egg were increased, basophilic substance was distributed in egg envelope around only. The yolk vesicles were changed to yolk mass in accordance with development. The fertilized egg was of ellipsoidal, adhesive type and yellowish, have a single micropyle in the area of the animal pole. The fertilized egg envelope consisted of three layers, an outer adhesive layer, a middle layer consisting of 6 lamellae alternating layers and an inner electron dense layer. An outer surface of the fertilized egg envelope was arranged by adhesive fibrous structures. In conclusion, it is summarized that the oogenesis of false dace were the increase of cell size, the formation and accumulation of yolk, and decrease of basophilic intensity in cytoplasm. These ultrastructural characteristics of fertilized egg envelope from false dace can be utilized in taxonomy of teleost.

Proliposomal Clenbuterol Patch for Transdermal Delivery (프로리포솜을 이용한 클렌부테롤의 경피흡수 제제화)

  • Lee, Young-Joo;Chung, Suk-Jae;Lee, Min-Hwa;Shim, Chang-Koo
    • Journal of Pharmaceutical Investigation
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    • v.27 no.4
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    • pp.303-311
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    • 1997
  • Proliposomal patch of clenbuterol, ${\beta}_2-agonist$ bronchodilator, was prepared and its feasibility as a novel transdermal drug delivery system was examined. Proliposomal granules containing clenbuterol was prepared by a standard method using sorbitol and lecithin with (Rx 2) or without cholesterol (Rx 1). The porous structure of sorbitol in the proliposomes was maintained allowing tree flowability of the granules. Following contact with water, the granules were converted probably to liposomes almost completely within several minutes. It indicates that proliposomes may be hydrated, when they are applied on the skin under occlusive condition in vivo, by the sweat to form liposomes. Clenbuterol release from Rx 1 and Rx 2 proliposomes to pH 7.4 isotonic phospate buffer (PBS) across cellulose membrane (mol. wt. cut-off of 12000-14000) was retarded significantly compared with that from the mixture of clenbuterol powder and blank proliposomes. Interestingly, proliposomes prepared with lecithin and cholesterol (i.e., Rx 2 proliposomes) showed much more retarded release of clenbuterol than proliposomes prepared only with lecithin (i.e.. Rx 1 proliposomes), indicating that clenbuterol release from proliposomes can be controlled by the addition of cholesterol to the proliposomes. Proliposomal patches were prepared using PVC film as an occlusive backing sheet, two sides adhesive tape (urethane, 1.45 mm thickness) as a reservoir for proliposome granules and Millipore MF-membrane (0.45 mm pore size) as a drug release-controlling membrane. Rx 1 or Rx 2 proliposomes containing 4.6 mg of clenbuterol were loaded into the reservoir of the patch. Clenbuterol release from the patches to pH 7.4 PBS was determined using USP paddle (50 rpm)-over-disc release method. Clenbuterol release from the proliposomal patches was much more retarded even than from a matrix type clenbuterol patch (Boehringer Ingelheim ltd). Being consistent with clenbuterol release from the proliposomal granules, the release from the patches was highly dependent on the presence of cholesterol in the proliposomes : Patches containing Rx 2 proliposomes showed several fold slower drug release than patches containing Rx 1 proliposomes. When the patch containing Rx 1 proliposomes was applied on to the back of a hair-removed rat, clenbuterol concentration in the rat blood was maintained during 6-72 hrs. Transdermal absorption of clenbuterol from the patch was accelerated when the patch was prehydrated with 50 ml of pH 7.4 PBS before topical application. Above results indicate that sustained transdermal delivery of clenbuterol is feasible using proliposomal patches if the cholesterol content and pore size of the release rate-controlling membrane of patches, for example, are appropriately controlled.

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Regulation of an Outer Membrane Protein, OmpW, Expression and Its Biological Function in Salmonell typhimurium (Salmonella typhimurium 외막 단백질 OmpW의 발현조절 및 기능에 관한 연구)

  • Yoo, Ah-Young;Yu, Jong-Earn;Yang, Ji-Seon;Kim, Young-Hee;Bae, Chang-Ho;Oh, Jeong-Il;Kang, Ho-Young
    • Journal of Life Science
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    • v.18 no.11
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    • pp.1606-1611
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    • 2008
  • Outer membrane proteins (OMPs) expressed in the Gram negative bacteria such as Salmonella play multiple functions including material transports, adhesive factors and reception of external signals. This study has been focused on an OmpW protein known as a protein required to form a hydrophobic porin in outer membrane. We have constructed a S. typhimurium CK10 mutant deleting an ompW gene on chromosome. The CK10 strain was more tolerant to SDS than the wild-type strain did. As increase of salt concentration in the culture media, significantly decreased amount of OmpW protein in cells were detected. The maximum OmpW protein was expressed in the absence of salt supplement. However, the growth of CK10 strain was indistinguishable compared to that of the wild-type strain at the variable osmotic conditions. The biological role of differential OmpW expression in response to osmotic conditions remains to be investigated.

BIOCOMPATIBILITY OF ABSORBABLE COLLAGEN MEMBRANES IN HUMAN PDL-DERIVED FIBROBLASTS IN VITRO (인간 치주인대 유래 섬유모세포에 대한 흡수성 교원질 차폐막의 생체적합성)

  • Kwon, Yong-Dae;Lee, Baek-Soo;Jue, Sung-Sook
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.32 no.3
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    • pp.272-278
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    • 2006
  • Purpose: This study is designed to evaluate biocompatibility of three types of absorbable collagen GBR membrane in vitro. Material and Method: The human PDL fibroblasts culture was obtained through typical way and the cells used in the experiment was forth passage. The membranes examined were Experimental group A, B, C. All the 3-experimental groups were made of bovine pericardium and the membranes were excised into 5$\times$5mm respectively. The samples of the membranes were fixed on the 24-well plate with the double-sided adhesive tape. Then, 2ml of cell suspension which included $2{\times}10^4$cells was inoculated into the 24-well plate, and the cells were cultured for 1 week. Cellular viability and the alkaline phosphatase activity were measured with ELISA. The membranes in the culture were processed to examine with SEM. Results: The survival rate was highest in control and Experimental group A is the next, group B and group C in order of the value. The values are analyzed for statistical difference using Wilcoxon test. All the values of experimental groups are significantly lower than those of control, and the vaules among the experimental groups significantly differ from each other. Alkaline phosphatase level was identical order with the viable cell rate. SEM examination revealed that the PDL fibroblasts adherent on culture dish (control) and group A were spindle-shaped, but on group B and C, the cells were round-shaped without processes.

Ultrasonographic Assessment of the Cutaneous Changes Induced by Topical Use of Novel Peptides Comprising Laminin 5

  • Park, Kyong Chan;Kim, Se Young;Khan, Galina;Park, Eun Soo
    • Archives of Plastic Surgery
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    • v.49 no.3
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    • pp.304-309
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    • 2022
  • Background Laminin 5, which is found in the basement membrane of dermal-epidermal junction (DEJ), is a major adhesive component and associated with proliferating and migrating keratinocytes. In this study, we hypothesized that the topical application of the skin care products containing the novel peptides might restore the DEJ structure by deriving deposition of laminin 5 and promoting the keratinocyte migration. Here, we evaluated the restoration of DEJ by measuring the skin thickness. Methods Single-center retrospective analysis was performed on a total of 13 patients who underwent skin care using Baume L.C.E. (France, Laboratories d' Anjou) between January and March 2021. All patients applied the skin care agent for 2 weeks only on their left hand dorsum. Before the initiation of the application and after 2 weeks, both their hands were evaluated on photography and ultrasound. And the patients were asked to rate their satisfaction with the questionnaire after 2 weeks. Results There was no obvious improvement in photographic assessment and questionnaire. The post-pre difference of skin thickness in ultrasound images was, in left hand, 0.1 ± 0.37 in distal point and 0.1 ± 0.35 in proximal point; and, in right hand, 0 ± 0.17 in distal point and 0 ± 0.15 in proximal point, respectively. The pre-post difference was statistically significant in proximal point (p = 0.035). Conclusion Topical application of novel peptide derivative comprising laminin 5 demonstrated cutaneous changes including skin thickness, as assessed by ultrasound. Further studies using other modalities including dermal density measurement, three-dimensional photography, optical coherence tomography, or skin biopsy would be helpful to determine the skin-improving effects.

Silicone Rubber Blended with Polyurethane as the Matrix for Ion-Selective Membrane Electrodes

  • Lee, Hyun Jung;Rho, Kyung Lae;Kim, Chang Yong;Oh, Bong Kyun;Cha, Geun Sig;Nam, Hakhyun
    • Analytical Science and Technology
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    • v.8 no.4
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    • pp.623-630
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    • 1995
  • Silicone rubber-based sodium-selective membranes are developed for solid-state ion sensors. It was shown that the potetiometric performance of SR-based membranes are greatly dependent on the type of neutral carriers employed; among the three ionophores, N,N,N',N'-tetracyclohexyl-1,2-phenylenedioxydiacetamide (ETH 2120), bis[(12-crown-4)methyl]dodecylmethylmalonate (D12C4DMM) and monensin methyl ester (MME), examined, only ETH 2120 was compatible with the SR-based matrix. Addition of about 20 wt% plasticizer to the SR-based matrix provided the resulting membranes with potentiometric properties essentially equivalent to those of the corresponding PVC-based membranes. Owing to the strong adhesive strength of SR-based membranes, the CWEs coated \vith those membranes exhibited long lifetime with conventional electrode-like performance. Blending of PU into the SR matrix increased the lifetime of CWEs from two weeks to one month.

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Improvement in Long-term Stability of Pd Alloy Hydrogen Separation Membranes (팔라듐 합금 수소분리막의 내구성 향상)

  • Kim, Chang-Hyun;Lee, Jun-Hyung;Jo, Sung-Tae;Kim, Dong-Won
    • Journal of the Korean institute of surface engineering
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    • v.48 no.1
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    • pp.11-22
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    • 2015
  • Pd alloy hydrogen membranes for hydrogen purification and separation need thermal stability at high temperature for commercial applications. Intermetallic diffusion between the Pd alloy film and the porous metal support gives rise to serious problems in long-term stability of Pd alloy membranes. Ceramic barriers are widely used to prevent the intermetallic diffusion from the porous metal support. However, these layers result in poor adhesion at the interface between film and barrier because of the fundamentally poor chemical affinity and a large thermal stress. In this study, we developed Pd alloy membranes having a dense microstructure and saturated composition on modified metal supports by advanced DC magnetron sputtering and heat treatment for enhanced thermal stability. Experimental results showed that Pd-Cu and Pd-Ag alloy membranes had considerably enhanced long-term stability owing to stable, dense alloy film microstructure and saturated composition, effective diffusion barrier, and good adhesive interface layer.

Fine structure of the silk spinning system in the caddisworm, Hydatophylax nigrovittatus (Trichoptera: Limnephilidae)

  • Hyo-Jeong Kim;Yan Sun;Myung-Jin Moon
    • Applied Microscopy
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    • v.50
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    • pp.16.1-16.11
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    • 2020
  • Silk is produced by a variety of insects, but only silk made by terrestrial arthropods has been examined in detail. To fill the gap, this study was designed to understand the silk spinning system of aquatic insect. The larvae of caddis flies, Hydatophylax nigrovittatus produce silk through a pair of labial silk glands and use raw silk to protect themselves in the aquatic environment. The result of this study clearly shows that although silk fibers are made under aquatic conditions, the cellular silk production system is quite similar to that of terrestrial arthropods. Typically, silk production in caddisworm has been achieved by two independent processes in the silk glands. This includes the synthesis of silk fibroin in the posterior region, the production of adhesive glycoproteins in the anterior region, which are ultimately accumulated into functional silk dope and converted to a silk ribbon coated with gluey substances. At the cellular level, each substance of fibroin and glycoprotein is specifically synthesized at different locations, and then transported from the rough ER to the Golgi apparatus as transport vesicles, respectively. Thereafter, the secretory vesicles gradually increase in size by vesicular fusion, forming larger secretory granules containing specific proteins. It was found that these granules eventually migrate to the apical membrane and are exocytosed into the lumen by a mechanism of merocrine secretion.

Fabrication of Field Emitter Arrays by Transferring Filtered Carbon Nanotubes onto Conducting Substrates

  • Jang, Eun-Soo;Goak, Jung-Choon;Lee, Han-Sung;Lee, Seung-Ho;Lee, Nae-Sung
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.06a
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    • pp.311-311
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    • 2009
  • Carbon nanotubes (CNTs) belong to an ideal material for field emitters because of their superior electrical, mechanical, and chemical properties together with unique geometric features. Several applications of CNTs to field emitters have been demonstrated in electron emission devices such as field emission display (FED), backlight unit (BLU), X-ray source, etc. In this study, we fabricated a CNT cathode by using filtration processes. First, an aqueous CNT solution was prepared by ultrasonically dispersing purified single-walled CNTs (SWCNTs) in deionized water with sodium dodecyl sulfate (SDS). The aqueous CNT solution in a milliliter or even several tens of micro-litters was filtered by an alumina membrane through the vacuum filtration, and an ultra-thin CNT film was formed onto the alumina membrane. Thereafter, the alumina membrane was solvated by acetone, and the floating CNT film was easily transferred to indium-tin-oxide (ITO) glass substrate in an area defined as 1 cm with a film mask. The CNT film was subjected to an activation process with an adhesive roller, erecting the CNTs up to serve as electron emitters. In order to measure their luminance characteristics, an ITO-coated glass substrate having phosphor was employed as an anode plate. Our field emitter array (FEA) was fairly transparent unlike conventional FEAs, which enabled light to emit not only through the anode frontside but also through the cathode backside, where luminace on the cathode backside was higher than that on the anode frontside. Futhermore, we added a reflecting metal layer to cathode or anode side to enhance the luminance of light passing through the other side. In one case, the metal layer was formed onto the bottom face of the cathode substrate and reflected the light back so that light passed only through the anode substrate. In the other case, the reflecting layer coated on the anode substrate made all light go only through the cathode substrate. Among the two cases, the latter showed higher luminance than the former. This study will discuss the morphologies and field emission characteristics of CNT emitters according to the experimental parameters in fabricating the lamps emitting light on the both sides or only on the either side.

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