• EDISON SW 활용 경진대회 논문집
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• 제2회(2013년)
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• pp.139-151
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• 2013

Understanding interactions between nanoparticles and lipid bilayer membranes is of great importance due to the potential applications in bio-nanotechnology such as drug deliveries, carrying genes, and utilization of integral membrane proteins. To investigate the dynamics of nanoparticle penetration and translocation into membranes, we performed dissipative particle dynamics simulations which use simple and intuitive coarse-grained models yet effectively describe hydrodynamic interactions in cell environment. We discuss the influence of the shape of nanoparticles as well as the properties of membranes including large membrane-embedded proteins that are found to significantly affect orientation of nanoparticles within membranes and, in turn, the minimum force required to translocate nanoparticles.

• Journal of Nutrition and Health
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• 제27권3호
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• pp.215-227
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• 1994

Changes in total lipid content, total cholesterol content and fatty acid composition of preterm milk were investigated during early lactation. Milk samples were collected from Korean mothers of 16 premature(34 to 36 weeks gestation age) infants on day 2 to 5(colostrum) and at 6 weeks(mature) postpartum. We estimated the lipid nutrition of preterm milk by comparing with the lipids of term milk. The total lipid content of preterm colostrum was significantly lower than the lipid content of preterm mature milk(p<0.001). Lipid content, determined gravimetrically in colostrum and matured milk, was 1.50g/이 and 3.2g/dl, respectively. Also the total cholesterol content(mg/dl) in preterm milk tends to increase from 14.16mg/dl to 15.20mg/dl, while the total cholesterol(mg/g lipid) concentration higher significantly in colostrum(12.36mg/g) than in mature(5.73mg/g)(p<0.001). The total unsaturated fatty acid contents in preterm milk were higher in colostrum than in mature milk and the total saturated fatty acids were higher in mature milk. The average DHA contents of colostrum and matured milk was 0.64%, 0.53% and the P/M/S ratio of preterm milk were 0.63 : 1.05 : 1.00, 0.47 : 0.79 : 1.00, respectively. Also, $\omega$6/$\omega$3 ratio of preterm milk were 2.35 in colostrum and 5.81 in mature. Therefore, colostrum in preterm milk contained higher amounts of $\omega$3 PUFA than mature milk. The levels of total lipid in preterm milk were higher than term milk. Also, preterm milk is richer in cholesterol, and long chain polyunsaturated fatty acid than term. It appears that the milk secreted by mothers who delivered prematurely differs from milk in several important respect. These components may serve as precursors for membrane, myelin development in the preterm infants. Therefore, it would be necessary to study further into the machanism of how the gestation age might affect to the lipid composition in human milk. These data may provide a basis for better construction of infant formaulas to provide more adequately for the lipid requirements of the Korean premature infant.

• The Korean Journal of Physiology and Pharmacology
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• 제2권4호
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• pp.529-539
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• 1998

The effects of membrane surface charge originated from lipid head groups on ion channels were tested by analyzing the activity of single large conductance $Ca^{2+}-activated\;K^+$ (maxi K) channel from rat skeletal muscle. The conductances and open-state probability ($P_o$) of single maxi K channels were compared in three types of planar lipid bilayers formed from a neutral phosphatidylethanolamine (PE) or two negatively-charged phospholipids, phosphatidylserine (PS) and phosphatidylinositol (PI). Under symmetrical KCl concentrations $(3{\sim}1,000\;mM)$, single channel conductances of maxi K channels in charged membranes were $1.1{\sim}1.7$ times larger than those in PE membranes, and the differences were more pronounced at the lower ionic strength. The average slope conductances at 100 mM KCl were $251{\pm}9.9$, $360{\pm}8.7$ and $356{\pm}12.4$ $(mean{\pm}SEM)$ pS in PE, PS and PI membranes respectively. The potentials at which $P_o$ was 1/2, appeared to have shifted left by 40 mV along voltage axis in the membranes formed with PS or PI. Such shift was consistently seen at pCa 5, 4.5, 4 and 3.5. Estimation of the effect of surface charge from these data indicated that maxi K channels sensed the surface potentials at a distance of $8{\sim}9\;{\AA}$ from the membrane surface. In addition, similar insulation distance ($7{\sim}9\;{\AA}$) of channel mouth from the bilayer surface charge was predicted by a 3-barrier-2-site model of energy profile for the permeation of $K^+$ ions. In conclusion, despite the differences in structure and fluidity of phospholipids in bilayers, the activities of maxi K channels in two charged membranes composed of PS or PI were strikingly similar and larger than those in bilayers of PE. These results suggest that the enhancement of conductance and $P_o$ of maxi channels is mostly due to negative charges in the phospholipid head groups.

• Animal cells and systems
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• 제15권3호
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• pp.211-218
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• 2011

Fragmentation in human pre-implantation embryos has been suggested as the process of apoptosis. We have previously demonstrated a direct relationship between the increased reactive oxygen species (ROS) and apoptosis in human pre-implantation embryos. ROS is known to suppress the function of mitochondria in which steroidogenic acute regulatory protein (StAR) and peripheral-type benzodiazepine receptor (PBR) are presented. Therefore, the purpose of this study was to examine the expression of StAR and PBR in human pre-implantation embryos and to evaluate whether reduction of these proteins is associated with apoptosis. Apoptosis was detected by annexin V-fluorescein isothiocyanate (FITC) and mitochondrial membrane potential was measured by 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethyl-benzimidazolyl-carbocyanine iodide (JC-1). Immunofluorescence staining and Western blotting were applied to examine the expression of StAR and PBR in the embryos. Lipid droplets in the embryos were stained with Oil Red O. The fragmented pre-implantation embryos were stained with annexin V-FITC, but not the normal ones. The mitochondria with active membrane potential were present less in the fragmented embryos compared with the non-fragmented embryos. We also confirmed that both StAR and PBR were expressed in the embryos and their expression levels were lower in the fragmented ones. In addition, the number and size of lipid droplets were increased in the fragmented embryos. The present study provides evidence that reduction of StAR and PBR in human pre-implantation embryos is associated with an increase in the lipid droplets leading to apoptosis.

• 한국식품영양과학회지
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• 제32권8호
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• pp.1328-1336
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• 2003

본 연구는 우리나라에서 발병률이 높은 간암의 발생과정에서 정어리유와 d-limonene의 섭취가 미치는 영향을 세포막 지질조성 및 PKC활성도를 통해 조사하여 이들의 항암 작용관련 기전을 규명 하고자 하였다. 따라서 이유된 흰쥐를 지방산 조성이 아주 다른 옥수수유, 정어리유를 15% 수준으로 공급하고 d-limonene 섭취군은 5%수준으로 공급하여 실험군에서는 발암물질인 DEN을 2회 복강 주사하고 PB를 물에 섞어 주어 20주간 사육하여 membrane fraction의 지방산 조성 및 지질의 조성, glutathione-S-transferase, PKC 활성도를 조사하여 아래와 같은 결과를 얻었다. 간 세포막의 콜레스테롤과 인지질 함량에 대한 C/PL ratio는 옥수수유군에서 발암물질 투여나 d-limonene의 섭취에 따른 효과가 없었으나 정어리 유군에서는 발암물질 투여시, d-limonene 섭취시 유의적인 감소를 나타내어 식이지방의 종류에 따라 발암물질과 d-limonene의 작용이 차이가 있는 것으로 나타났다. Membrane fraction의 인지질 조성은 CL을 제외한 PE, PI, PG, PC, PS와 PE/PC ratio등 모두에 있어서 식이지방의 종류, 발암물질의 투여, d-liomnene섭취에 따른 차이가 나타나지 않았다. 세포막의 지방산 조성을 나타내는 n-6/n-3 ratio가 정어리유군에서 옥수수유군보다 유의적으로 낮았고, 옥수수유군에서는 발암물질 투여나 d-limonene의 섭취에 따라 유의적으로 증가했으나 정어리유군에서는 발암물질과 d-limonene에 의한 차이가 없었다. Cytosolic PKC의 활성은 식이지방의 종류와 발암물질 투여에 따른 차이는 없었고, d-limonene의 섭 취에 따라 유의적 감소를 나타냈으며, 막부착 PKC의 활성은 옥수수유군에서 유의적으로 높았고, d-limonene 섭취에 따라 감소 경향을 발암물질 투여에 따라서는 증가 경향을 보였으나 유의적인 차이를 나타내지는 않았다. GST활성은 식이 지방의 종류에 따른 차이는 없었으나 발암물질 투여와 d-limonene 섭취에 따라 유의적으로 증가하였으며, 발암물질과 d-limonene을 같이 공급시에 더욱 더 유의적으로 증가하였다. 이상의 실험 결과를 종합에 보면 암화과정에 일어나는 지방의 대사가 식이지방의 종류에 따라 차이를 보이며, 특히 정어리유군에서 d-limonene에 의한 C/PL ratio가 감소하여 막 유동성에 변화를 초래하고, 이에 따라 membrane bound enzyme의 활성에 변화를 가져오는 것으로 생각된다. 따라서 식이지방의 종류가 암의 발생에 미치는 영향이 다르고, 막부착 PKC 활성도를 감소시켜 발암을 억제하는 효과가 있으며, 이 효과는 지방의 종류에 따라 차이가 있는 것으로 생각된다. 최근 n-3 지방산이나 d-limonene이 PKC expression을 감소시키고, apopotosis 촉진 단백질의 발현을 증가시켜 tumor cell의 apoptosis를 증가시킨다고 하여 n-3 지방산과 d-limonene의 또 다른 발암억제기전을 설명하고 있다. 그러나 n-3 지방산과 d-limonene의 상호효과에 대한 연구는 부족한 실정이므로 d-limonene과 n-3 지방산의 교호작용에 의한 발암억제 기전에 대해서는 더 많은 연구가 필요하다고 하겠다.

• 생명과학회지
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• 제13권5호
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• pp.692-698
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• 2003

뇌 세포막 유동성의 촉진 및 LPO생성의 억제효과는 중풍 등 뇌혈관질환을 억제할 수 있을 뿐만 아니라 혈관성치매의 예방에도 크게 기여할 것으로 기대된다[26,18]. 따라서 솔잎 EtOAc획분을 하루 25, 50, 100 mg/kg BW로써 SD계 랫트에 45일동안 투여하여 뇌조직중의 세포막 유동성 (membrane fluidity : MF), 기초 및 유도활성산소(BOR 및 IOR), 산화적 스트레스로서 과산화지질(lipid peroxide : LPO) 및 산화단백질(oxidized protein : OP), 그리고 리포푸신(lipofuscin : LF)의 축적에 미치는 영향을 평가하여 보았다. 솔잎 EtOAc획분의 투여에 의하여 뇌조직의 mitochondria 및 microsome획분에서 용량의존적으로 MF가 증가효과가 나타났지만, EtOAc-100 투여그룹의 mitochondria 획분에서만 약 10%의 유의적인 MF의 증가효과가 인정되었다. 뇌조직의 mitochondria에서 기초 및 유도활성산소로서 BOR 및 IOR의 생성은 EtOAc-50 및 EtOAc-100투여그룹에서 각각 9.2∼10.2% 및 17.1∼24.0%의 유의적인 억제효과가 인정되었고, microsomes에서 BOR 및 IOR의 생성은 EtOAc-50및 EtOAc-100투여그룹에서 각각 11.6∼16.6% 및 12.1∼16.1%의 유의적인 억제효과가 인정되었다. 산화적 스트레스에 미치는 영향은 mitochondria 및 microsomes획분에서 EtOAc-50 및 EtOAc-100투여그룹에서 각각 8.5∼12.0% 및 11.6∼18.5%의 유의적인 LPO의 생성 억제효과가 인정되었지만, 뇌조직의 두 획분에서 OP의 생성은 EtOAc획분의 용량의존적으로 억제되었지만, 유의성은 인정할 수 없었다. 또한 뇌조직에서 LF의 축적도 EtOAc획분의 용량 의존적으로 억제효과가 나타났지만, 유의성은 인정할 수 없었다. 이상의 결과에서 평가하여 볼 때 솔잎 EtOAc획분의 투여는 뇌조직의 유동성을 촉진하고 LPO의 생성을 효과적으로 억제할 수 있지만, 현재의 투여농도에서는 OP 및 LF의 생성을 방지할 수 없을 것으로 생각된다.

• 생명과학회지
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• 제13권5호
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• pp.684-691
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• 2003

솔잎 EtOAc획분을 하루 25, 50, 100 mg/kg체중으로서 SD계 랫트에 45일동안 투여하여 간장획분의 세포막 유동성(membrane fluidity MF), 기초 및 유도활성산소(BOR 및 IOR), 산화적 스트레스로서 과산화지질(lipid peroxide : LPO) 및 산화단백질(oxidized protein : OP), 그리고 리포푸신(lipofuscin : LF)의 축적에 미치는 영향을 평가하여 보았다. 솔잎 EtOAc획분의 투여에 의하여 간장의 mitochondria 및 microsome획분에서 어느 정도 MF가 증가하였지만, 유의성은 EtOAc-100 투여그룹의 mitochondria획분에서만 인정되었다. 기초 및 유도활성산소로서 BOR 및 IOR의 생성 억제효과는 간장의 두 획분의 EtOAc-50 및 EtOAc-100투여그룹에서 유의적인 활성산소의 생성 억제 효과가 인정되었다. 산화적 스트레스에 미치는 영향에서는 mitochondria획 분에서 는 EtOAc-100투여그룹에서, 그리고 microsome획분에서는 EtOAc-50 및 EtOAc-100투여그룹에서 유의적인 LPO의 생성 억제효과가 인정되었고, mitochondria 획분에서는 EtOAc-50 및 EtOAc-100투여그룹에서 유의적인 OP의 생성 억제효과가 인정되었지만, microsome 획분에서는 아무런 유의성도 인정할 수 없었다. 그렇지만, 간장의 클로로포름층에서 측정한 LF의 축적은 EtOAc-25, EtOAc-50 및 EtOAc-100 투여그룹에서 다같이 유의적인 LF의 축적 억제효과가 인정되었다. 이상의 결과에서 평가하여 볼 때 솔잎 EtOAc획분의 투여는 간장의 유동성을 촉진하고 산화적 스트레스를 효과적으로 억제할 수 있을 것으로 기대된다.

• Journal of Microbiology and Biotechnology
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• 제19권8호
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• pp.810-817
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• 2009

The effect of cryoprotectants (maltodextrin+glycerol) and cryoprotectants+antioxidant [ascorbic acid and/or butylated hydroxytoluene (BHT)] mixtures on the survival, electrolyte leakage, and lipid degradation of freeze-dried Weissella paramesenteroides LC11 during storage was investigated and compared with that of the control (cells without additives) over a 90-day storage period at 4 or $20^{\circ}C$ in glass tubes with water activity ($a_w$) of 0.23. The survival, electrolyte leakage, and lipid degradation were evaluated through colony counts, electrical conductivity, and thiobarbituric acid reactive substances (TBARS) content, respectively. The fatty acids composition was determined by gas chromatography, in both the total lipid extract and the polar lipid fraction, and compared with that of the control after the 90-day storage period. As the storage proceeded, increases in leakage value and TBARS content, as well as a decrease in viability, were observed. After 90 days of storage, the major fatty acids found in both the total lipid extract and the polar lipid fraction were palmitic (16:0), palmitoleic (16:1), stearic (18:0), oleic (18:1), linoleic (18:2), and linolenic (18:3) acids. The survival, leakage value, TBARS content and 18:2/16:0 or 18:3/16:0 ratio were the greatest for the protected strain held at $4^{\circ}C$. Cells with the cryoprotectants+BHT mixture showed the highest percentage of survival and 18:2/16:0 or 18:3/16:0 ratio in both lipid extracts, as well as the lowest leakage value and TBARS content after the 90-day storage period. Drying cells with the cryoprotectants+BHT mixture considerably slowed down polar lipid degradation and loss of membrane integrity, resulting in improved viability during storage.

• 대한임상독성학회지
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• 제1권1호
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• pp.6-11
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• 2003

Various forms of dialytic techniques are available for detoxification. Hemodialysis, hemoperfusion and hemofiltration (hemodialfiltration) are the main treatment modalities. Because these modalities are rather invasive and expensive, it must be decided in balance of the risk and benefit to the patient. The prime consideration in the decision is based on the clinical features of poisoning; hemodialysis or hemoperfusion should be considered in general if the patient's condition progressively deteriorates despite intensive supportive therapy. The hemodialysis technique relies on passage of the toxic agent through a semipermeable membrane so that it can equilibrate with the dialysate and subsequently removed. It needs a blood pump to pass blood next to a dialysis membrane, which allows agents permeable to the membrane to pass through and reach equilibrium. Solute (or drug) removal by dialysis has numerous determinants such as solute size, its lipid solubility, the degree to which it is protein bound, its volume of distribution etc. The technique of hemoperfusion is similar to hemodialysis except there is no dialysis membrane or dialysate involved in the procedure. The patient's blood is pumped through a perfusion cartridge, where it is in direct contact with adsorptive material (usually activated charcoal) that has a coating material such as cellulose. This method can be used successfully with lipid-soluble compounds and with higher-molecular-weight compounds than for hemodialysis. Protein binding does not significantly interfere with removal by hemoperfusion. In conclusion, hemodialysis, hemoperfusion and hemofiltration can be used effectively as adjuncts to the management of severely intoxicated patients.

• Applied Microscopy
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• 제24권4호
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• pp.13-31
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• 1994

피자식물내 엽육조직 미세구조연구의 일환으로 형태해부학적으로 매우 다른 특성을 지닌 국화과 Dubautia속 식물 3종(Dubautia scabra var. leiophylla, D. knudsenii, D. scabra var. leiophylla, D. knudsenii)의 엽육조직이 연구되었다. 부모종 엽육조직의 형태해부학적 특성과 그들의 잡종 엽육조직세포의 분화 정도를 추정하기 위하여 palisade mesophyll내의 chloroplasts, microbodies, mitochondria 및 grana내의 thylakoid membrane system, phytoferritin-like structures, plastoglobuli와 starch grain 등 엽록체 내부의 초미세구조 형질들을 중점적으로 비교 분석하였다. 잡종의 엽육조직세포들은 형태해부학적 엽육형질 및 thylakoidal membrane system 등의 형질에서 부모종 엽육조직의 중간적 특성 (intermediacy)을 나타내어 전형적인 bilateral inheritage를 보여주었으며, thylakoid membrane number/granum, phytoferritin-like structures, starch grain의 분포 등에서는 어느 한 부모종 형질과 더 유사하게 관찰되었다. 미소체 및 미토콘드리아는 대체로 비슷한 양상으로 관찰되었고 phytoferritin-like structures는 국화과 식물 엽록체내에서 처음 보고되는 미세구조이다.