• Title/Summary/Keyword: multilamellar

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Effects of Local Anesthetics on the Fluidity of Synaptosomal Plasma Membrane Vesicles Isolated from Bovine Brain (국소마취제가 Synaptosomal Plasma Membrane Vesicles의 유동성에 미치는 영향)

  • Yun, Il;Han, Suk-Kyu;Baik, Seung-Wan;Kim, Nam-Hong;Kang, Jung-Sook;Chung, Joong-Ki;Lee, Eun-Joo
    • The Korean Journal of Pharmacology
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    • v.24 no.1
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    • pp.43-52
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    • 1988
  • To elucidate the mechanism of action of local anesthetics, the effects of local anethetics on the microenvironment of the lipid bilayers of synaptosomal plasma membrane vesicles (SPMV) isolated from bovine brain and dimyristoylphosphatidylcholine (DMPC) multilamellar liposomes were investigated employing the intermolecular excimer fluorescence technique and differential scanning calorimetry (DSC). The relative intensities of excimer and monomer fluorescence of pyrene are a simple linear function of the viscosity of a homologous series of solvents. The microviscosity(${\eta}$)of the hydrocarbon region of SPMV was measured by this method and the value was $57.3{\pm}5.3\;cP$ at $37^{\circ}C$. In the presence of lidocaine-HCl and procaine-HCl, the values decreased to $46.5{\pm}5.1\;cP$ and $54.7{\pm}4.8\;cP$, respectvely. The differential scanning thermograms of DMPC multilamellar liposomes showed that local anesthetics significantly lowered the phase transition temperature, broadened the thermogram peaks, and reduced the size of the cooperative unit. These results indicate that local anesthetics have significant fluidizing effects on biomembranes and perturbation of membrane lipids may produce some, but not all, of their pharmacological actions.

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The Differentiation and Ultrastructural Characteristics of Type II Pneumocyte in Early Human Fetal Lungs (태아 허파의 초기 발달 중 과립허파꽈리세포의 분화와 미세구조의 특징)

  • Yoo, Dong-Hwa;Kim, Dae-Joong;Kim, Sung-Su;Kim, Kyung-Yong;Lee, Won-Bok
    • Applied Microscopy
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    • v.29 no.3
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    • pp.291-301
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    • 1999
  • The differentiation and ultrastructural characteristics of type II pneumocyte was investigated using 7 cases of human fetal lungs from 9 to 20 weeks of gestation by transmission electron micropscopy. The result obtained were as follows. 1. From the pattern of epithelium, type II pneumocyte was not discernable, but with the gradual development of gestation, the epithelium of the future pulmonary alveoli was transformed from pseudostratified columnar into simple cuboidal epithelium after 15 weeks of geatation. 2. The multilamellar body very specific to type II pneumocyte was observed at first at 9 weeks of gestation. Besides, another characteristics of the cell were also observed such as cytoplasmic inclusion body, granular inclusionbody,multivesicularinclusionbodyanddensebody. 3. The number and size of multilamellar body increased, but those of other inclision bodies decreased at 19 and 20 weeks of gestation. In summary, type II pneumocytes (or precursor cells) with multilamellar body and another characteristic inclusion bodies were observed in the human fetal lungs from 9 weeks of gestation. And so, it is suggested that the differentiation of type II pneumocyte starts at or before 9 weeks of gestation.

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The effects of digitonin and glycyrrhizin liposomes

  • Yu, Byung-Sul;Choi, Hyun-Ok
    • Archives of Pharmacal Research
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    • v.9 no.3
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    • pp.119-125
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    • 1986
  • Digitonin is a strong hemolysin and glycyrrhizin has protective activity against the deterring effect of other hemolytic saponins. The interaction of these saponins with liposomes was studied as a function of cholesterol in membrane. In the case of multilamellar vesicles, which act as ideal osmometers, digitonin distrupted the barrier function of liposomes composed of phosphatidyl choline, dicetyl phosphate and cholesterol, however, did not influence on cholesterol-lacking liposomes. Glycyrrhizin had similar effect on liposomes irrespective of cholesterol in membrane. In the test with large unilamellar vesicles, digitonin increased the lysis with increasing cholesterol content in membrane, but glycyrrhizin showed no detectable change in cholesterol-containing liposomes. These results suggest that incorporation of cholesterol into liposomes increases the susceptibility to digitonin, resulting in lysis of liposomes, and that the inhibitory effect of glycyrrhizin against other hemolytic saponins in cholesterol-independent.

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Investigation of the Incorporation Efficiency of $\beta$-Carotene into Liposomes

  • Rhim, Chae-Hwan;Lee, Kyong-Eun;Yuk, Hyun-Gyun;Lee, Sang-Chun;Lee, Seung-Cheol
    • Preventive Nutrition and Food Science
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    • v.5 no.3
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    • pp.177-178
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    • 2000
  • Chemical and photochemical precesses during food storage an preparation rapidly degrade $\beta$-carotene, the most active form of carotenoids. We investigated the possibility of liposomes as tool to preserve $\beta$-carotene. Liposomes with $\beta$-carotene were prepared as multilamellar vesicles by using soybean phosphatidylcholine, in terms of the ratio of $\beta$-carotene to phospholipid and pH. Incorporated efficiency was 99.7% at 1:0.05 of phospholipid : $\beta$-carotene and at pH 9.0. As the concentration of $\beta$-carotene increased, the incorporated efficiency increased progressively. pH did not affect the incorporation efficiency greatly.

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DEVELOPMENT OF DRIED LIPOSOMES CONTAUBUBG $\beta$-GALACTO-SIDASE FOR THE DIGESTION OF LACTOSE IN MILK.

  • Lee, Na-Choi;Kim, Chong-Kook
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1996.04a
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    • pp.283-283
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    • 1996
  • The hydrolyzed-lactose milk for the lactase-deficient subject is sweeter than whole milk, and some subjects dislike its taste. To overcome this shortcoming the dried liposomes containing ${\beta}$-galactosidase to digest lactose in milk after drinking were prepared and examined the possible application of this dried liposomes to the lactase-deficient subjects. To improve the stability of conventional liposome suspension, the dried liposomes in the presence of trehalose were prepared by the dehydration-rehydration vesicles method. Small unilamellar vesicles, prepared with egg phosphatidyl cholesterol, and cholesterol, were mixed with ${\beta}$-galactosidase solution and then ;up[jo;ozed. The freeze-dried liposome was rehydrated and centrifuged. The resultant multilamellar vesicles were mixed with trehalose(4g/g lipid) and then lyophilized to produce final dried liposome. Trehalose increased the entrapping efficiency of liposomes by 3 fo1d compared to the liposomes without trehalose (13% vs. 46%).

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Interactions of Membrane and PMAP-23 Studied by $^{31}P$ solid-state NMR Spectroscopy

  • Kim, Si-Won;Kim, Suhk-Mann
    • Journal of the Korean Magnetic Resonance Society
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    • v.11 no.2
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    • pp.110-114
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    • 2007
  • [ $^{31}P$ ] powder pattern spectra were measured to investigate the aspects of the interaction between the MLV (Multilamellar vesicle) and PMAP-23, a membrane of cathelicidin family and then CSAs(chemical shift anisotropy) were calculated to indentify the extent of perturbation of phospholipid mobility by the peptides. We found that acidic phospholipid interacts strongly with PMAP-23, and the analogues which modified to increase the amphipathic property showed that larger change of CSA. The analogue which introduced positive charge showed the same effects with amphipathic property.

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Stability and Formation Mechanism for MLV liposomes with Phospholipid Film by Use of the Microfluidizer

  • Kim, In-Young;Seo, Bong-Seok
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.22 no.2
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    • pp.99-114
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    • 1996
  • The MLV liposomes have been developed in many drugs and cosmetics fields. The phospholipid base is made from ceramides, cholesterol, cholesteryl ester, lecithin, lanolin ester, and B-sitosterol, and surfactants are made by using (PEG)n-sitosterol(n=5) and K-cetyl phosphate. We made visicles stable by passing samples through Microfludizer and croated multilamellar vesicles to make MLV liposomes similar to the structure of men's skin. In order to make MLV liposomes, we created lipid membrane films which a mixure of phospholipid base and polyol group was reacted above Tc(95$^{\circ}C$) by gelation for 3 hours. As the optimum conditions of Microfluidizer, we figured out 700 bar for the passing pressure of samples, 4$0^{\circ}C$ for its temperature, and 3 times of frequency to pass through samples. Our MLV liposomes is stable on conditions of a low temperature(5$^{\circ}C$) and a high temperature(45$^{\circ}C$), which is not to be split in a large range. We produced our own moisturizing cream which has a good affinity to skin by means of this system.

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Studies on the Haustorium of Cuscuta japonica Choisy (새삼(Cuscuta japonica Choisy)의 흡기에 관한 연구 I. 숙주조직 침투전의 흡기)

  • 이재두
    • Journal of Plant Biology
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    • v.28 no.4
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    • pp.261-270
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    • 1985
  • The portion of Cuscuta japonica haustorium which lies external to the host tissues, the upper haustorium, was investigated at the light- and electron-microscopic levels. The haustorium lightly contacted with the host was formed by the expansion of the epidermis and cortex of the stem at the contact side, and to have a group of meristematic cells within the haustorial cortex. When such a haustorium was closely contacted with the host, the meristematic region transformed into a primordial structure of the endophyte (endophyte primordium, EP) which may penetrate into the host tissues. EP consisted of the three kinds of cell group: dividing cells at the adaxial or proximal side; large, elongate cells (idioblasts) at the middle portion,; compressed cells at the abaxial or basal side. the idioblasts were characterized by the presence of large nucleus, dense cytoplasm, several small vacuoles, and abundant cell organelles including the multilamellar structures and cytosegresomes, and thus suggested to have a high metabolic activity. The features of the EP were discussed in relation to the possibility of the penetrating into host tissues.

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Multivesicular bodies 및 Cytolysomes에 관(關)한 전자현미경적(電子顯微鏡的) 연구(硏究)

  • Kim, Woo-Kap;Kim, Chang-Whan;Park, Hong-Duok;Yang, He-Young
    • Applied Microscopy
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    • v.6 no.1
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    • pp.21-32
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    • 1976
  • The origins and the functions of the multi vesicular bodies and the various structures of the membranes related to the cytolysomes were studied in the mycelium cells of Rhizopus nigricans, Aspergillus niger and A. ochraceus, in the hymenium and basidium cells of Agricus bisporus sand Rhizopogon rubesecens, in the cells of assimilation tissue of Marchtantia polymorpha and Pogonalum inflexum and in the mesophyll cells of Pteridium aqiulinum, Pinus densiflora, Ginkgo biloba and Panax ginseng fixed with glutaraldehyde-paraformaldehyde-$ OsO_4$. In Rhizopus nigricans, Aspergillus niger, A. ochraceus, Agricus bisporus sand Rhizopogon rubescens, the concentric multilamellar, multivesicular, myelin-vesicle-tubular and concentric parallel-lamellar complexes were originated from the plasmalemma, while in Marehantia polymorpha, Pogonatum inflexum, Pteridium aquilinum, Pinus densiflora, Ginkgo biloba and Panax ginseng, they were originated from plasmalemma and the cytoplasm. The structures originated from the plasmalemma may be grouped into multi vesicular body and myelin-like structure, both forming the secondary vacuoles or protruding into the central vacuoles and finally degrading, In some cases, endoplasmic reticulum within the cytoplasm encloses some part of the cytoplasm to form a circle where the membranous lamellae increase in number, while the enclosed cytoplasm decrease to be eventually replaced by the multilamellar structure which is released into the vacuoles and subsquently degraded. The structures originated from the cytoplasm are believed to be the cytosegresomes or cytolysomes closely related to the differentiation of the vacuoles. The possible fate of these structures are also discussed.

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Effects of Residual Solvents in the Phase Transition, Transition Enthalpy, and Transition Temperature of Phospholipid Membranes (잔류 유기 용매가 모델 세포 지질막의 상전이, 상전이 엔탈피 및 상전이 온도에 미치는 영향)

  • An, Eun Seol;Choi, Jae Sun;Lee, Dong Kuk
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.40 no.2
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    • pp.163-170
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    • 2014
  • Lipid membranes composed of phosphatidylcholine (PC) are used in biophysical study to mimic cellular membranes and interactions between the membrane and chemicals, where organics solvents are used in dissolving lipids or chemicals. Later, solvents are removed from the solution under nitrogen gas at room temperature, followed by the further removal of the solvent at vacuum condition for several hours. In this process, some solvents are easily removed under described conditions above and others are required more severe conditions. In this study, $^{31}P$ solid-state nuclear magnetic resonance (SSNMR) techniques and differential scanning calorimetry (DSC) were used to see any changes in the line shapes of $^{31}P$ NMR spectra of multilamellar vesicles (MLVs) samples of POPC and in the phase change temperature of multilamellar vesicles (MLVs) of DPPC in DSC thermogram with or without any residual solvents. The thermodynamic parameters associated with the solvents did exhibit noticeable changes depending on solvent types. Thus, it is concluded that solvents should be carefully chosen and removed completely and experimental results should also be interpreted with caution particularly for the experiments investigating lipid phase changes and related topics.