• 대한약리학회지
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• 제31권3호
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• pp.271-278
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• 1995

Barbiturates의 분자적 약리학적 작용기전 연구에 기초자료를 제공키 위하여 본연구를 수행하였다. 분자적 약리작용 기전 연구에서는 무엇보다도 선행되어야 하는 것이 barbiturates가 신경세포막에서 어느 부위에 주로 분포되는가를 알아내는 데에 있다. 쥐(Rat)의 뇌로부터 분리한 synaptosomal plasma membrane vesicles (RSPMV)를 분리한 후 이 RSPMV 외측 단층(outer monolayer)의 소수성 부위와 친수성 부위에 barbiturates가 분포되는 경향을 형광 probe 법으로 검색하였다. 세포막 외측 단층의 친수성 부위에 분포되는 형광 probe N-octadecylnaphthyl-2-amino-6-sulfonic acid (ONS)와 소수성 부위에 분포되는 형광 probe12-(9-anthroyloxy)stearic acid (AS)를 각각 봉입한 후 형광소광법으로 barbiturates의 분포를 측정한 결과는 다음과 같다. 1) 대부분의 barbiturates가 RSPMV 외측 단층의 친수성 부위(표면)에 분포되고 소수성 부위 (hydrophobic region)에 극히 소량만이 분포된다는 것을 확인하였다. 2) 마취효과를 크게 일으키는 barbiturates일수록 소수성 부위에 분포되는 양이 증가하였다. barbiturates 종류에 따른 RSPMV 외측 단층 소수성 부위에의 분포 크기는 thiopental sodium > pentobarbital > hexobarbital > amobarbital > phenobarbital의 순위였다.

• 대한약리학회지
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• 제29권1호
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• pp.157-163
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• 1993

n-Alkanols의 분자적 약리작용기전 탐구에 기초자료를 제공하기 위하여 소의 신선한 대뇌피질로부터 분리한 synaptosomal plasma membrane vesicles (SPMV) 지질 이중층의 측방확산운동에 미치는 n-alkanols의 영향을 형광 probe법으로 검색하였다. n-Alkanols는 SPMV 지질 이중층의 측방확산운동 범위와 속도를 농도 의존적으로 증가시켰고 1-nonanol까지는 탄소수가 두개 증가될 때마다 그 효력은 약 10배 가량 증가되었으나 탄소수 10개인 1-decanol의 효력은 오히려 감소되는 경향을 나타내었다.

• 대한임상검사과학회지
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• 제51권1호
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• pp.78-85
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• 2019

막 단백질은 심장질환, 암과 같은 우리 주변에서 흔히 발생하는 질병에 관련되어 있다. 이러한 암과 같은 특정한 질환 상태에서, 막 단백질과 관련된 신호 전달의 비정상은 세포분열을 통제하지 못하고 증가시킬 수 있으며 막 단백질의 발현에 변화가 생긴다. 막 단백질은 지질 이중층으로 이루어진 소수성 환경을 가지고 있어 불안정하기 때문에 막 단백질을 추출해서 연구를 수행하는데 어려움이 있다. 이번 연구에서는 최적화된 막 단백질 추출법을 확인하고자 서로 다른 두 가지 추출법의 효율성을 평가하였다. 두 가지 방법으로, high-speed centrifuge법과 reagent법이 비교되었다. 비교 분석결과, 미토콘드리아 내막 단백질 분석에는 high-speed centrifuge법이 효율적이고, 소포체 막 단백질 분석에는 reagent법이 유용함을 확인하였다. 게다가 유전자 온톨로지 소프트웨어를 이용해서 추출된 막 단백질의 기능분석을 진행하였을 때, 유전자 온톨로지는 reagent법에서 소포체 막 단백질에 연관된 반응이 활성화 되는 것을 확인할 수 있었다. 프로세스 네트워크 분석에서, high-speed centrifuge법에서는 하나의 클러스터를 형성화는 반면, reagent법에서는 네 개의 클러스터를 형성하는 것을 시각화하여 확인하였다. 결론적으로, 두 가지 분석법은 서로 다른 하위 막 단백질의 분석에 유용함을 확인할 수 있었다. 이러한 결과를 토대로, 막 단백질을 분석할 때, 표적의 세부 막 단백질을 고려하여 방법론을 선택하는데 도움을 줄 것으로 기대된다.

• Journal of Pharmaceutical Investigation
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• 제11권2호
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• pp.1-10
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• 1981

Phospholipids were examined for their capacity to protect human erythrocytes against hemolysis induced by hypotonic solution, p-hydroxymercuribenzoate or hematin. The following results were obtained. 1. Phosphatidyl choline, lysophosphatidyl choline and phophatidyl ethanoleamine as well as chlorpromazine prevented the osmotic hemolysis of human erythrocytes which occurred due to water influx into erythrocytes from medium, but showed no effect on hematin-induced hemolysis which occurred without the volume change of erythrocytes. 2. Human erythrocytes were found to be most sensitive to the antihemolytic action of phospholipids among mammalian erythrocytes from sheep, rabbit, rat and mouse. 3. Phospholipids at the concentrations showing their strong antihemolytic effect on human erythrocytes against osmotic hemolysis had no influence on methylene blue uptake and volume change of erythrocytes in hypotonic solution. 4. Phospholipids increased erythrocyte deformability 2 to 3 times over control group and there was aclose relationship between their antihemolytic action and increase of deformability as a function of their concentrations. 5. The phospholipids increased the resistance to osmotic hemolysis of human erythrocytes by increasing membrane elasticity through their incorporation into lipid bilayer without altering glucose metabolism and water influx to erythrocytes.

• Journal of Chest Surgery
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• 제25권4호
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• pp.347-355
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• 1992

The precise mechanism of the Excitation-Contraction Coupling is still uncertain. But the concept that Ca2+ induced Ca2+ release [CICR] from the Ryanodine receptor in the sarcoplasmic reticulum [foot structure] may play a major role in E-C coupling has been widely accepted since 1970`s. It is believed that increased cytosolic Ca2+ followed by CICR is main contributor for E-C coupling of striated muscle. Resulting phenomena of ischemic /post-reperfusion myocyte is increased cytosolic Ca2+, even to the absence of Ca2+ in reperfusate. So intracellular inhibitor to CICR might prevent the ischemic and reperfusion damage of myocardial cells. The relatively purified foot protein, especially heavy sarcoplasmic reticulum rich, of the skeletal muscle was incorporated into the black lipid bilayer [Phosphatidyl ethanolamine: Phosphatidyl serine=l: 1]. Under the steady state of membrane potential [+20 mV], ionic current through Ryanodine receptor was measured with Cs+ as charge carrier. In the cis chamber [Cytoplasmic side], Mg2+ strongly inhibited CICR of Ryanodine receptor[Kd=6.2 nM]. In conclusion, naturally existing intracellular free Mg2+ can inhibit CICR from intracellular Ca2+ reservior [heavy SR]. So post-ischemic or post-reperfusing myocardium could be preserved using additional free Mg2+ in cardioplegic solution or reperfusate, otherwise the optimal concentration is undetermined.

• KSBB Journal
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• 제32권2호
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• pp.160-167
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• 2017

Coating of individual cells with organic or inorganic materials has drawn a great deal of attention, because it provides the cells with physicochemical durability, which would contribute to the development of bioreactors, biosensor, and lab-on-a-chip, as well as to the fundamental studies in single cell-based biology. Although many strategies have been developed for coating of microbial cells, limited methods are available to coat mammalian cells because most mammalian cells do not have a robust membrane or exoskeleton. Instead, they are enclosed in a lipid bilayer, which is fluidic and vulnerable to changes in its environments. It is more difficult to treat mammalian cells in vitro than microbial cells because the surfaces of mammalian cells are not protected or reinforced by a tough coat. In this work, we report a cytocompatible and degradable nanocoat for mammalian cells. Three types of mammalian cells (HeLa cells, NIH 3T3 fibroblasts, and Jurkat T cells) were individually coated within metal-polyphenol. To maintain the viability of the mammalian cells, we performed the whole processes under strictly physiological culture conditions, and carefully selected nontoxic materials.

• Bulletin of the Korean Chemical Society
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• 제33권12호
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• pp.3998-4002
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• 2012

With continuing progress of nanotechnologies and various applications of nanoparticles, one needs to develop a quick and fairly standard assessment tool to evaluate cytotoxicity of nanoparticles. However, much cytotoxicity studies on the interpretation of the interaction between nanoparticles and cells are non-mechanistic and time-consuming. Here, we propose a simple screening method for the analysis of the interaction between several AgNPs (5.3 to 64 nm) and fluorescence-dye containing vesicles ($12{\mu}m$) acting as a biomimetic cell-membrane. Fluorescence-dye containing vesicle was prepared using a fluorescence probe (1,6-diphenyl-1,3,5-hexatryene), which was intercalated into the lipid bilayer due to their hydrophobicity. Zeta potential of all materials except for bare-AgNPs (+32.8 mV) was negative (-26 to -54 mV). The morphological change (i.e., rupture and fusion of vesicle, and release of dye) after mixing of the vesicle and AgNPs was observed by fluorescence microscopy, and fluorescence image were different with coating materials and surface charge of x-AgNPs. In the results, we found that the surface charge of nanoparticles is the key factor for vesicle rupture and fusion. This proposed method might be useful for analyzing the cytotoxicity of nanoparticles with cell-membranes instead of in vitro or in vivo cytotoxicity tests.

• Molecules and Cells
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• 제45권9호
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• pp.603-609
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• 2022

Cells can communicate in a variety of ways, such as by contacting each other or by secreting certain factors. Recently, extracellular vesicles (EVs) have been proposed to be mediators of cell communication. EVs are small vesicles with a lipid bilayer membrane that are secreted by cells and contain DNA, RNAs, lipids, and proteins. These EVs are secreted from various cell types and can migrate and be internalized by recipient cells that are the same or different than those that secrete them. EVs harboring various components are involved in regulating gene expression in recipient cells. These EVs may also play important roles in the senescence of cells and the accumulation of senescent cells in the body. Studies on the function of EVs in senescent cells and the mechanisms through which nonsenescent and senescent cells communicate through EVs are being actively conducted. Here, we summarize studies suggesting that EVs secreted from senescent cells can promote the senescence of other cells and that EVs secreted from nonsenescent cells can rejuvenate senescent cells. In addition, we discuss the functional components (proteins, RNAs, and other molecules) enclosed in EVs that enter recipient cells.

• 대한의용생체공학회:의공학회지
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• 제45권1호
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• pp.20-25
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• 2024

Extracellular vesicles (EVs) are nano-sized lipid bilayer vesicles released by cells. EVs act as messengers for cell-to-cell communication. Inside, it contains various substances that show biological activity, such as proteins, lipids, nucleic acids, and metabolites. The study of EVs extracted from terrestrial organisms and stem cells on inflammatory environments and tissue regeneration have been actively conducted. However, marine organisms-derived EVs are limited. Therefore, we have extracted EVs from sea urchins belonging to the Echinoderm group with their excellent regenerative ability. First, we extracted extracellular matrix (ECM) from sea urchin gonads treated with hypotonic buffer, followed by collagenase treatment, and filtration to collect ECM-bounded EVs. The size of sea urchin gonad-derived EVs (UGEVs) is about 20-100 nm and has a round shape. The protein content was higher after EVs burst than before, which is evidence that proteins are contained inside. In addition, proteins of various sizes are distributed inside. PKH-26 was combined with UGEVs, which means that UGEVs have a lipid membrane. PHK-26-labeled UGEVs were successfully uptaken by cells. UGEVs can be confirmed to have the same characteristics as traditional EVs. Finally, it was confirmed that Schwann cells were not toxic by increasing proliferation after treatment.

• BMB Reports
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• 제33권3호
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• pp.221-227
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• 2000

The distribution of barbiturates in the model membranes of total lipids (SPMVTL) and total phospholipids (SPMVPL) extracted from synaptosomal plasma membrane vesicles was determined by employing a fluorescent probe technique. The two fluorescent probes 2-(9-anthroyl)stearic acid and 12-(9-anthroyl)stearic acid were utilized as probes for the surface and the hydrocarbon interior of the outer monolayer of the SPMVTL and SPMVPL, respectively. The Stern-Volmer equation of fluorescent quenching was modified to calculate the relative distribution. The analysis of preferential quenching of these probes by barbiturates indicates that pentobarbital, hexobarbital, amobarbital and phenobarbital are predominantly distributed on the surface area, while thiopental sodium has an accessibility to the hydrocarbon interior of the outer monolayer of the SPMVTL and SPMVPL. From these results, it is strongly suggested that the more effective penetration into the hydrocarbon interior of the outer monolayer of the membrane lipid bilayer could result in a higher general anesthetic activity.