• Archives of Pharmacal Research
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• 제13권1호
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• pp.64-68
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• 1990

The stabilization effect of .alpha.-tocopherol incorporated into liposomal phospholipid membrane was investigated by fluorospectrophotometry and UV-visible spectretarded by the presence of .alpha.-tocopherol in the bilayer of liposomal phospholipid membrane relative to cholesterol-containing liposomes and pure phospholipid liposomes. .alpha.-tocopherol-containing liposomes prolonged the oxidation of liposomes-embedded heme as those of cholesterol-containing liposomes and pure phospholipid liposomes. Thus .alpha.-tocopherol-containing liposomes may be useful for the carrier systems of nutrients and drugs to phospholipid bilayer and stabilized liposomes.

• Journal of Periodontal and Implant Science
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• 제34권4호
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• pp.711-722
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• 2004

The purpose of this study is to evaluate the regenerated bone histollogically using titanium reinforced ePTFE(TR-ePTFE) membrane and to investigate cell occlusiveness, wound stabilization and tissue integration of TR-ePTFE membrane. Adult male rabbits (mean BW 2kg) and TR9W (W.L.Gore&Associate.INC,USA) were used in this study. Intramarrow penetration defects were surgically created with round carbide bur(HP long #6) on calvaria of rabbits. TR-ePTFE membrane was applied to defect. Then guided bone regeneration was carried out using TR-ePTFE membrane and resorbable suture. At 2,4,8,12 weeks after the surgery, animals were sacrificed. Nondecalcified specimens were processed for histologic analysis. The result and conclusion of this study were as follows: 1. TR-ePTFE membrane had good ability of biocompatibility and cell occlusiveness. 2. space making for guided bone regenerayion was good at TR-ePTFE membrane. 3. Tissue integration was not good at TR-ePTFE membrane. So, wound stabilization was not good. 4. At 8 weeks, 12 weeks after GBR procedure, bone formation was seen. From the above results, TR-ePTFE membrane fixed tightiy on alveolar bone might be recommended for the early bone formation.

• Membrane and Water Treatment
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• 제2권4호
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• pp.207-223
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• 2011

Supported Liquid Membranes (SLMs) have been widely studied as feasible alternative to traditional processes for separation and purification of various chemicals both from aqueous and organic matrices. This technique offers various advantages like active transport, possibility to use expensive extractants, high selectivity, low energy requirements and minimization of chemical additives. SLMs are not yet used at large scale in industrial applications, because of the low stability. In the present paper, after a brief overview of the state of the art of SLM technology the facilitated transport mechanisms of SLM based separation is described, also introducing the small and the big carrousel models, which are employed for transport modeling. The main operating parameters (selectivity, flux and permeability) are introduced. The problems related to system stabilization are also discussed, giving particular attention to the influence of membrane materials (solid membrane support and organic liquid membrane (LM) phase). Various approaches proposed in literature to enhance SLM stability are also reviewed. Modification of the solid membrane support, creating an additional layer on membrane surface, which acts as a barrier to LM phase loss, increases system stability, but the membrane permeability, and then the flux, decrease. Stagnant Sandwich Liquid Membrane (SSwLM), an implementation of the SLM system, results in both high flux and stability compared to SLM. Finally, possible large scale applications of SLMs are also reviewed, evidencing that if the LM separation process is opportunely carried out (no production of byproducts), it can be considered as a green process.

• 한국막학회:학술대회논문집
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• 한국막학회 1995년도 추계 총회 및 학술발표회
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• pp.5-9
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• 1995

In the dry-jet-wet-spinning process of a hollow fiber membrane, the polymer solution is pumped into a coaxial tube, jet spinneret. The threadline emerging from the spinneret is stabilized by an internal coagulating medium(liquid or gas) as it emerges from the jet orifice. The nascent hollow thread is further stabilized in a quench bath as shown in Fig. 1. In this scheme, three mechanism of formatiota(temperature gradient, solvent evaporation, and solvent-nonsotvent exchange) can be combined. The changes which promote stabilization often play a dominant role in determining the ultimate fiber wall structure as well. Hence, in pratice, hollow fiber stabilization and development of membrane structure are commonly inseparable. However, fiber dimension(the inside diameter and wall thickness of the hollow fiber) is mainly a rheological problem and is determined by dope pumping rate, spinneret diatance from the coagulation bath, inner coagulant flow rate, and fiber draw-rate. Besides rheological phenomena play a prominent part in the final properties of the hollow fiber.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2012년도 추계학술대회 논문집
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• pp.665-666
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• 2012

• 한국자기공명학회논문지
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• 제23권3호
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• pp.67-72
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• 2019

Caveolae are small plasma membrane invaginations that play many roles in signal transduction, endocytosis, mechanoprotection, lipid metabolism. The most important protein in caveolae is the integral membrane protein, caveolin, which is divided into three families such as caveolin 1, caveolin 2, and caveolin 3. Caveolin 1 and 3 are known to incorporate palmitate through linkage to three cysteine residues. Regulation of the protein palmitoylation cycle is important for the cellular processes such as intracellular localization of the target protein, membrane association, conformation, protein-protein interaction, and activity. However, the detailed aspect of individual palmitoylation has not been studied. In the present work, the role of each lipid modification at three cysteines was studied by NMR. Our results suggest that each lipid modification at the natively palmitoylation site has its own roles. For example, lipidations to C106 and C129 are play a role in structural stabilization, however, interestingly, lipid modification to C116 interrupts the structural stabilization.

• Advances in Traditional Medicine
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• 제7권4호
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• pp.395-408
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• 2007

This study reports the analgesic, anti-inflammatory and membrane-stabilizing property of alcoholic extract of Ophiorrhiza nicobarica (ON), a wild herb, used as an anti-infective ethnomedicine of Nicobarese and Shompen tribes of Great Nicobar Island, India. We for the first time investigated the analgesic and antiinflammatory potential of this herb in acute, subacute and chronic model of inflammation in Swiss albino mice and Wistar albino rats, along with sheep RBC-induced sensitivity and membrane stabilization. The acetic acid induced writhing, tail flick and tail immersion tests are used as a model for evaluating analgesic activity; while the carrageenin-induced paw oedema was used as the model for acute inflammation, dextran-induced oedema as sub-acute and cotton-pellateinduced granuloma as chronic inflammatory model. The probable mode by which ON mediate its effect on inflammatory conditions was studied on sheep RBC-induced sensitivity and membrane stabilization. The in vitro results revealed that the ON extract possesses significant (P < 0.05) dose dependent analgesic and antiinflammatory activity at 200 and 300 mg/kg and its fractions at 50 mg/kg, p.o. respectively, compared to the control groups. However, the extract failed to exhibit membrane-stabilizing property as it unable to reduce the level of haemolysis of RBC exposed to hypotonic solution. The acute toxicity studies of ON extract in rats and mice revealed that the extract was nontoxic even up to 3.0 g/kg body weight of the animals, with a high safety profile. We have isolated ursolic acid, ${\beta}$-sitosterol and harmaline respectively, from the bioactive part of the extract. The results indicated that the O. nicobarica is indeed beneficial in primary health care, and suggest that its anti-inflammatory activity may not be related to membrane-stabilization.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1994년도 한국생물과학협회 학술발표대회
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• pp.200.1-200
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• 1994

No Abstract, See Full Text

• International Journal of Industrial Entomology and Biomaterials
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• 제10권2호
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• pp.125-129
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• 2005

Ribosome-associated membrane protein 4 (RAMP4) is a membrane protein that exposes its N-terminal hydrophilic portion on the cytoplasmic side and spans the membrane close to the C-terminal end. RAMP4 has previously been reported to belong to the set of proteins that remains associated with membrane-bound ribosomes, and controls the glycosylation of major histocompatbility complex class II-associated invariant chain. RAMP4 also may be relative to the stabilization of membrane proteins in response to stress, with other components of translocon, and molecular chaperons in ER. Application of 5'-RACE technique with specially designed primer, we cloned a 715 bp cDNA fragment which contains a 195 bp ORF, termed RAMP4. The deduced protein has 64 amino acid residues and contains a putative transmembrane-spanning domain at the COOH terminus.

• 한국지반환경공학회 논문집
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• 제23권1호
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• pp.5-13
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• 2022

In tropical regions, lateritic soil is frequently used in road embankment. However, it is one of the sources of road failure owing to its low strength. Generally, cement and lime are used as stabilizers for lateritic soil, but they are not environmentally friendly. Some studies try to use eggshells, for they are food waste and share the same chemical composition as lime. Previous researchs have shown that eggshell powder could enhance the strength of lateritic soil. This research investigated the effect of particle size of the eggshell powder and the effect of the protein-membrane presence in the eggshell on stabilizing capacity of soil. Through laboratory tests, unconfined compressive strength was examined for various particle sizes. The particle size of eggshell powder ranging between 150 ㎛ and 88 ㎛ was appropriate size that made an excellent stabilizer at 3% concentration. On the other hand, the protein-membrane reduced the stabilizing ability of the eggshell powder when the content of eggshell powder is less than 4% in soil. Numerical analysis of road embankment was performed based on the results obtained in the laboratory tests. It is shown that the eggshell powder has improved the stability of the sub-base of the road embankment.