• Title/Summary/Keyword: Molecular structures

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A Study on DPPC Lipid Membrane and its Carbohydrate Mixture Membrane for Preparation of a Functional Membrane (기능성 막 제조를 위한 DPPC 지질막과 탄수화물 혼합막에 관한 연구)

  • Jeong, Teak-Suh;Rhee, Jae-Seong;Lee, Ki-Chang;Hong, Jang-Hoo
    • Applied Chemistry for Engineering
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    • v.7 no.2
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    • pp.252-260
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    • 1996
  • In this article, we investigate into the structural changes of liposome to design its functional membranes by the synthesis of two types of liposomes, DPPC liposome and DTAB of hydrocarbon substance/DPPC liposome. The changes of membrane structures are evaluated by the CF fluorescent intensity measured above and below the phase transition temperature of the membrane, $t_c=41^{\circ}C$. CF fluorescent intensities are enhanced by the CF leakage from DPPC liposome at $45^{\circ}C$, while no changes are observed at $20^{\circ}C$. Under the same conditions, it is observed that the intensity enhanced by CF leakage from DPPC/DTAB liposome is larger than that of DPPC liposome alone, which suggests that DPPC/DTAB liposome has irregular arrangement. Under the presence of $Ca^{2+}$, Quin 2 fluorescent intensity in either DPPC liposome or DPPC/DTAB liposome is significantly increasing at $45^{\circ}C$, while almost none of the changes are observed at $20^{\circ}C$. The fluorescent intensity of DPPC liposome turns out to be larger than that of DPPC/DTAB liposome, which suggests that the DPPC/DTAB liposome is structurally more stable than the DPPC liposome. Additionally, when the analysis is done to observe changes in the shapes of membrane surfaces with ANS fluorescent, ANS fluorescent under DPPC or DPPC/DTAB liposome shows each of different appearances at $45^{\circ}C$ and $20^{\circ}C$ respectively. This result indicates that its respective membrane fluidity is changing above and below of the designated temperatures in phase transition. As to the magnitude of change of its membrane fluidity, DPPC liposome is much larger than DPPC/DTAB liposome. As far as the temperature in phase transition measured by DSC are concerned, it is $41^{\circ}C$ and $32^{\circ}C$ for DPPC and DPPC/DTAB liposome respectively, which suggests that DPPC/DTAB liposome has an irregular molecular arrangement in its structure. That is, it is summed up that DPPC/DTAB turns out to be structurally stable, even so, its structure is irregularly arranged.

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Characterization of Lactate Dehydrogenase in Acanthogobius hasta (풀망둑(Acanthogobius hasta) 젖산탈수소효소의 특성)

  • Yum, Jung-Joo
    • Journal of Life Science
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    • v.18 no.2
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    • pp.264-272
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    • 2008
  • The lactate dehydrogenase (EC 1.1.1.27, LDH) isozymes in tissues from Acanthogobius hasta were characterized by biochemical, immunochemical and kinetic methods. The activities of LDH in skeletal muscle and eye tissues were 65.30 and 53.25 units, but LDH activities in heart and liver tissues were very low. LDH/CS (EC 4.1.3.7, citrate synthase) in skeletal muscle was the highest as 22.29. Specific activities of LDH in brain, eye and skeletal muscle were 56.45, 38.04 and 11.0 units/mg, respectively. The LDH isozymes in tissues were separated by polyacrylamide gel electrophoresis after immunoprecipitation with antiserum against $A_4,\;B_4$ eye-specific $C_4$ and liver-specific $C_4$. LDH $AC_4$ isozymes were detected predominantly in skeletal muscle, brain and eye tissues, and $B_4$ isozyme was detected in heart. Anodal eye-specific $C_4$ and cathodal liver-specific $C_4$ were coexpressed in A. hasta. The eye-specific $C_4$ isozyme showed higher activity in eye tissue, but liver-specific $C_4$ isozyme showed lower activity in liver. As a result, one part of molecular structures in $A_4\;and\;C_4,\;A_4\;and\;B_4$, and eye-specific $C_4$ and liver-specific $C_4$ were similar, but in $B_4\;and\;C_4$ were different with each other. Therefore the subunit A may be conservative in evolution, and the evolution of subunit B seems to be faster than that of subunit A. The LDH $A_4$ isozyme of skeletal muscle was purified in the fraction from elution with NAD+ containing buffer of affinity chromatography and eye-specific $C_4$ isozyme was eluted right after $A_4$, so the structure of eye-specific $C_4$ isozyme is similar to $A_4$. And LDH activity remained 35.22-43.47% as a result of the inhibition by pyruvate, the Michaelis-Menten constant values for pyruvate was 0.080-0.098 mM, and Vmax were 153.85 units, 35.09 units in skeletal muscle and eye, respectively. Also the $B_4$ isozyme was the thermo-stablest and $C_4$ was stabler than $A_4$ isozyme. The optimum pH of LDH was 6.5. The results mentioned above indicate that isozymes in tissues showed the properties between LDH $A_4\;and\;B_4$ isozyme as A. hasta was adapted to hypoxic conditions. Also LDH seems to function more effectively under anaerobic condition because LDH in skeletal muscle and eye tissues have high affinity for pyruvate.

On the Secretion and Functions of Equine Chorionic Gonadotropin (말의 융모성 성선자극 호르몬의 분비와 기능)

  • Min, K.S.
    • Korean Journal of Animal Reproduction
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    • v.24 no.2
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    • pp.125-142
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    • 2000
  • 13). Analysis of a purified preparation of eCG revealed that its $\beta$ -subunit consists of 149 amino acids, which was confirmed by the molecular cloning of its cDNA. There seem to be at least four to six, or even as many as 11, O-glycosylation sites on the extended C-tenninal region of the eCG $\beta$-subunit. Interestingly, eCG is a unique member of this family, as it appear to be a single molecule that possesses both LH- and FSH-like activities. Using the cDNA prepared from mRNA extracted from equine placental and pituitary tissues, we cloned the cDNA of eCG $\alpha$- and $\beta$ -subunits and eFSH $\beta$ -subunit. The mRNA expression of each subunit seems to be independently regulated, which may account for differences in the quantities of $\alpha$ - and $\beta$ -subunits in the placenta and pituitary. Thus, eCG is a distinct molecule from the view points of its biological function and glycoresidue structures. Recombinant eCGs including the mutants which lack oligosaccharides will be useful tools for analyzing the structure-function relationships of gonadotropins in the horse as well as other species. Similar experiments will also clarify the proposed structure and biological functions for the glycoprotein hormones. These experimental are now possible, and hopefully a resolution of the existing controversy will be forthcoming in the near future.

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The Effect of Methanol on the Structural Parameters of Neuronal Membrane Lipid Bilayers

  • Joo, Hyung-Jin;Ahn, Shin-Ho;Lee, Hang-Rae;Jung, Sung-Woo;Choi, Chang-Won;Kim, Min-Seok;Bae, Moon-Kyoung;Chung, In-Kyo;Bae, Soo-Kyoung;Jang, Hye-Ock;Yun, Il
    • The Korean Journal of Physiology and Pharmacology
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    • v.16 no.4
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    • pp.255-264
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    • 2012
  • The structures of the intact synaptosomal plasma membrane vesicles (SPMVs) isolated from bovine cerebral cortexs, and the outer and the inner monolayer separately, were evaluated with 1,6-diphenyl-1,3,5-hexatriene (DPH) and 1,3-di(1-pyrenyl)propane (Py-3-Py) as fluorescent reporters and trinitrophenyl groups as quenching agents. The methanol increased bulk rotational and lateral mobilities of SPMVs lipid bilayers. The methanol increased the rotational and lateral mobilities of the outer monolayers more than of the inner monolayers. n-(9-Anthroyloxy)stearic acid (n-AS) were used to evaluate the effect of the methanol on the rotational mobility at the 16, 12, 9, 6, and 2 position of aliphatic chains present in phospholipids of the SPMVs outer monolayers. The methanol decreased the anisotropy of the 16-(9-anthroyloxy)palmitic acid (16-AP), 12-(9-anthroyloxy)stearic acid (12-AS), 9-(9-anthroyloxy)stearic acid (9-AS), and 6-(9-anthroyloxy)stearic acid (6-AS) in the SPMVs outer monolayer but it increased the anisotropy of 2-(9-anthroyloxy)stearic acid (2-AS) in the monolayers. The magnitude of the increased rotational mobility by the methanol was in the order at the position of 16, 12, 9, and 6 of aliphatic chains in phospholipids of the outer monolayers. Furthermore, the methanol increased annular lipid fluidity and also caused membrane proteins to cluster. The important finding is that was far greater increase by methanol in annular lipid fluidity than increase in lateral and rotational mobilities by the methanol. Methanol alters the stereo or dynamics of the proteins in the lipid bilayers by combining with lipids, especially with the annular lipids. In conclusion, the present data suggest that methanol, in additions to its direct interaction with proteins, concurrently interacts with membrane lipids, fluidizing the membrane, and thus inducing conformational changes of proteins known to be intimately associated with membranes lipids.

Evaluation of Therapeutic Effects of Cognitive-Behavioral Therapy in Patients with Panic Disorder using Serial $^{99m}Tc-ECD$ Brain Perfusion (공황장애 환자에서 $^{99m}Tc-ECD$ 뇌관류 SPECT를 이용한 인지행동치료 효과 평가)

  • Kim, Jung-Hee;Song, Ho-Chun;Yang, Jong-Chul;Lee, Byeong-Il;Heo, Young-Jun;Bom, Hee-Seung;Park, Tae-Jin;Min, Jung-Joon
    • Nuclear Medicine and Molecular Imaging
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    • v.40 no.6
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    • pp.302-308
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    • 2006
  • Purpose: Although several neuroanatomical models of panic disorder have been proposed, little is known regarding the neurological mechanisms underlying cognitive-behavioral therapy (CBT) in patients with panic disorder. This study was performed to identify the brain structures that show changes of regnioal cerebral blood flow (rCBF) after CBT in patients with panic disorder. Materials and Methods: Seven patients who were diagnosed as panic disorder by DSM-IV were treated with CBT for 8 weeks and twelve healthy volunteers joined in this study. Serial $^{99m}Tc-ECD$ brain perfusion SPECT images were acquisited and PDSS-SR (Self-Report version of Panic Disorder Severity Scale) and ACQ (Agoraphobic Cognitive Question) scores were measured just before and after CBT in all patients. Data were analyzed using SPM2. Results: Subjective symptoms were improved, and PDSS-SR and ACQ scores were significantly reduced ($14.9{\pm}3.9\;vs.\;7.0{\pm}1.8$, p<0.05; $30.3{\pm}8.5\;vs.\;21.6{\pm}3.4$, p<0.05, respectively) after CBT in panic patients. Before CBT, a significant increase of rCBF was found in the cingulate gylus, thalamus, midbrain, both medial frontal and temporal lobes of the panic patients compared to the normal volunteers. After CBT, we observed a significant rCBF decrease in the left parahippocamus, right insula and cingulate gyrus, both frontal and temporal lobes, and a significant rCBF increase in both the occipital lobes, left insula, both frontal and left parietal lobes. Conclusion: These data suggested that CBT is effective for panic disorder and diminish the activity of the brain areas associated with fear in panic disorder.

A Study on the Correlations between Molecular Structures of Soil Humins and Sorption Properties of Phenanthrene (토양 휴민(Humin)의 분자구조 특성과 Phenanthrene 흡착상수와의 상관관계에 대한 연구)

  • Lee, Doo-Hee;Eom, Won-Suk;Shin, Hyun-Sang
    • Journal of Korean Society of Environmental Engineers
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    • v.35 no.12
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    • pp.897-905
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    • 2013
  • In this study, sorption coefficients (${\log}K_{OC}$, n) for the binding of phenanthrene (PHE) to soil humins, insoluble fraction of soil humc substances (HS), were determined and relationship between the sorption coefficients and structural characteristics of the soil humins were investigated. The soil humins used in the present study were isolated from 7 different soils including 5 domestic soils, an IHSS standard and a peat soil, and characterized by elemental analysis and CPMAS $^{13}C$ NMR method. $^{13}C$ NMR spectral features indicate that the soil humins are mainly made up of aliphatic carbons (57.1~72.3% in total carbon) with high alkyl-C moiety, and the alkyl-C contents ($C_{Al-H,C}$, %) was in order of granite soil Hu (26~42%) > volcanic ash soil, HL Hu (23.9%) > Peat Hu (14.0%). The results of correlation study show that a positive relationship ($r^2$ = 0.77, p < 0.05) between organic carbon normalized-sorption coefficients ($K_{OC}$, mL/g) and alkyl-C contents($C_{Al-H,C}$, %), while negative relationship ($r^2$ = (-)0.74, p < 0.05) between Freundlich sorption parameter (n) and H,C-substituted aromatic carbon contents ($C_{Ar-H,C}$, %). The magnitude of $K_{OC}$ values are also negatively well correlated with polarity index (e.g., PI, N + O)/C) ($r^2$ = (-)0.74, p < 0.1). These results suggest that the binding capacity (e.g., $K_{OC}$) for PHE is increased in soil humin molecules having high contents of alkyl-C or lower polarity, and nonlinear sorption for PHE increased as the H,C-substituted aromatic carbon contents ($C_{Ar-H,C}$, %) in the soil humins increased. The PHE sorption characteristics on soil humins are discussed based on the dual reactive mode of sorption model.

Geochemical Characteristics of Granodiorite and Arenaceous Sedimentary Rocks in Chon-Ashuu Area, Kyrgyzstan (키르키스스탄 촌아슈 지역 화강섬록암질암 및 사질원 퇴적암의 지화학적 특징)

  • Kim, Soo-Young;Chi, Sei-Jung;Park, Sung-Won
    • Economic and Environmental Geology
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    • v.44 no.4
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    • pp.273-288
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    • 2011
  • Chon-Ashuu copper mining claim area is located, in terms of the geotectonic setting, in the northern part of the suture line which is bounded with the marginal part of Issik-kul micro-continent on the southern part of North Tien-Shan terrane. The geological blocks of Chon-Ashuu districts belong to the southern tip of Kazakhstan orocline. The rock formation of this area are composed of the continental crust or/and arc collage and the paleo-continental fragments-accretionary wedge complex of pre-Altaid orogenic materials. ASI(Alumina Saturation Index) of Paleozoic plutonic rocks in Chon-Ashuu area belong to the peraluminous and metaluminous rocks which were generated from fractional crystallization of Island and volcanic arc crusts in syn-post collisional plate. The geology of the ChonAshuu area consists of upper Proterozoic and Paleozoic rock formations. According to Harker variation diagrams for Chon-Ashuu arenaceous sedimentary rocks, the silty sandstone of Chon-Ashuu area showing the mineralogical immaturity were derived from Island arc or the marginal environments of active continent in Cambro-Carboniferous period. Numerous intrusive rocks of Chon-Ashuu area are distributed along north east trending tectonic structures and are bounded on four sides by the conjugate pattern. The most common type of the plutonic rocks are granodiorite and monzodiorite. According to the molecular normative An-Ab-Or composition (Barker, 1979), the plutonic rocks in Chon-Ashuu area are classified into tonalite - trondhjemite - granodiorite (TTG) series which are an aggregation of rocks which is the country rock of copper mineralization, that are formed by melting of hydrous mafic crust at high pressure.

Effect of Lignans from Schisandra chinensis Baillon on Seed Germination in Pepper (오미자 (Schisandra chinensis Baillon)로 부터 추출한 리그난이 고추종자의 발아에 미치는 영향)

  • Shin, Woo-Jung;Lee, You-Jin;Son, Beung-Gu;Kang, Jum-Soon;Lee, Yong-Jae;Park, Young-Hoon;Lee, Young-Geun;Kim, Yong-Cheol;Choi, In-Soo;Kim, Sun-Tae;Choi, Young-Whan
    • Journal of Life Science
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    • v.20 no.3
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    • pp.430-436
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    • 2010
  • In this study, the effects of dibenzocyclooctadiene on seed germination were investigated in pepper. Four $C_{18}$ dibenzocyclooctadiene lignans - schisandrin (1143.7 mg), schisandrin C (317.3 mg), gomisin A (261.4 mg) and gomisin N (213.4 mg) - were isolated from hexane extracts of the fruits of Schisandra chinensis. The molecular structures of the four lignans were elucidated based on spectroscopic analyses including 1D NMR experiments, and bi comparing their spectroscopic data with those of previous literatures. Seeds were immersed in $10^{-5}\;M$ schisandrin, $10^{-6}\;M$ schisandrin C and $10^{-7}\;M$ gomisin A and gomisin N for 1 hr and incubated at $25^{\circ}C$ in the dark for germination. Compared to untreated control, treatment with schisandrin C and gomisin A suppressed seed germination at 48 hrs after incubation, whereas treatment with gomisin N increased germination rate at 48 hrs after incubation. The results of the germination activity of the lignans from S. chinensis confirm their potential plant growth role, and the relative natural abundances of these metabolites suggest their potential use as natural plant growth regulators.

Isolation and Identification of a Photosensitizer from Pueraria thunbergiana Leaves that Induces Apoptosis in SK-HEP-1 Cells (P. thunbergiana 잎으로부터 SK-HEP-1세포에 대한 apoptosis를 유도하는 광과민성물질의 분리 및 구조동정)

  • Lee, Jun Young;Kim, Mi Kyeong;Ha, Jun Young;Kim, Yong Gyun;Hong, Chang Oh;Kim, So Young;Kim, Chung-Hwan;Kim, Keun Ki
    • Journal of Life Science
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    • v.24 no.3
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    • pp.242-251
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    • 2014
  • The objective of this study was to isolate a photosensitizer from Pueraria thunbergiana leaves that induces apoptosis in SK-HEP-1 cells. Column chromatography and thin layer chromatography were used to isolate active compounds from extracts of P. thunbergiana leaves. The structures of the isolated compounds were determined by 1D-NMR, 2D-NMR, and FAB-mass spectroscopy. A substance, named M4-3, was purified from the leaves of P. thunbergiana using various chromatography methods, and the absorbance of the substance was measured. The absorbance was highest at 410 nm, suggesting that the M4-3 substance was a different compound from chlorophyll a and b, which absorb at 410, 502, 533, and 607 nm. Further analyses revealed that the M4-3 compound was a $13^2$-hydoxy pheophorbide, a methyl ester with a molecular weight of 662. M4-3 was identified as a derivative compound of pheophorbide, with a structure that magnesium comes away from the porphyrin ring. The results of the analysis of the cytotoxicity of the M4-3 substance against the SK-HEP-1 cells revealed that it inhibited rates of cell growth by 40% and 80% at a concentration of 0.04 ${\mu}M$ and 0.08 ${\mu}M$, respectively. The M4-3 compound was found to be a photosensitizer for cytotoxicity because it was appeared only in light condition as examining activity in different irradiation conditions (light condition and nonlight condition) under the same concentration. Analysis of morphological changes in the cells following cell death induced by exposure to the M4-3 substance reveled representative phenomena of apoptosis (nuclear condensation, vesicle formation, and fragmentation of DNA). The induction of apoptosis was attributed to the compound's photodynamic activity.

Structural Characterization of the Anti-Complementary and Macrophage Activating Polysaccharides Isolated from Agaricus bisporus (양송이에서 분리한 보체계와 대식세포 활성화 다당류의 구조적 특성)

  • Kim, Byung-Hee;Kweon, Mee-Hyang;Lim, Wang-Jin;Sung, Ha-Chin;Yang, Han-Chul
    • Korean Journal of Food Science and Technology
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    • v.30 no.3
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    • pp.709-716
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    • 1998
  • Three kinds of anti-complementary system and macrophage activating polysaccharides, AB-20-Ia, AB-20-IIa-2a and AB-20-IVa-2 were isolated from the fruit body of Agaricus bisporus and their structures were characterized. The proteoglycan, AB-20-IVa-2 showing the most potent anti-complementary and macrophage activity was composed of glucose, galactose, mannose, xylose, fucose and arabinose in a molar ratio of 3.48:1.83:1.00:0.79:0.74:0.11 and its main component amino acids were phenylalanine (34.72%) and valine (27.84%). The neutral polysaccharides, AB-20-Ia and AB-20-IIa-2a showing lower activity than AB-20-IVa-2, consisted of xylose, glucose, mannose, fucose and arabinose in molar ratios of <0.05:<0.05:2.07:1.00:2.72 and 2.16:1.58:1.00:0.20:0.14, respectively. The molecular weights of AB-20-Ia, AB-20-IIa-2a and AB-20-IVa-2 were 840,000, 750,000 and 650,000 respectively. In the $^1H-\;and\;^{13}C-NMR$ spectra of AB-20-Ia and AB-20-IIa-2a, AB-20-Ia showed only ${\beta}-configuration\;(^1H:\;4.8\;ppm,\;^{13}C:\;107.0\;ppm)$ in the anomerization of the glycosidic linkages, while AB-20-IIa-2a had both ${\alpha}-anomer\;(^1H:\;5.4\;ppm,\;^{13}C:\;102.0\;ppm)\;and\;{\beta}-anomer$. Especially, AB-20-Ia and AB-20-IIa-2a showed acetyl signals $(^1H:\;2.5\;ppm,\;^{13}C:\;21.0\;ppm)$. In the methylation analysis of the three polysaccharides, high proportion of 1,6-linked glucofuranosyl residues were detected in AB-20-Ia, whereas 1,6-linked glucopyranosyl residues and branches linked at position 4 of those mainly contained in AB-20-IIa-2a. AB-20-IVa-2 consisted mainly of 1,2-linked xylofuranosyl residues and 1,6-linked glucopyranosyl residues and branches linked at position 3 of those.

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