• Journal of Nutrition and Health
• /
• v.23 no.7
• /
• pp.477-491
• /
• 1990

To observe the effect of dietary n6 linoleic acid, n6 gamma-linolenic acid and n3 alphalinolenic acid aon plasma lipid composition and platelet aggregation, twenty college women were divided into 4 groups and treated for 2 weeks with experimental diets supplying fat at 23% cal which were different only in fatty acid composition. Dietary fat was corn oil(CO) as a source of n6 linoleic acid(LA), perilla oil(PO) for n3 alpha-linolenic acid(ALA) and evenign primrose oil(EPO) for n6 gamma-linolenic acid(GLA). Plasma cholesterol level was slightly decreased by PL(13.5g) but significantly increased by equal amount of CO. However, there was similar hypocholeaterolemic effect when double amount of CO(27.0g), was supplemented. Therefore, total fat unsaturation may be more important factor for plasma cholesterol-lowering effect than the structure of fatty acid itself. Plasma cholesterol level was not lowered by supplement of GLA in CO diet. There was similar trend in hypotriglyceridemic effect by PO and CO as in plasma cholesterol. Plasma TG level was rather increased but not significantly by GLA supplement to CO diet. Overall, plasma lipid-lowering effect was greater by ALA than LA and GLA effect was not greater than by LA. GLA supplement did not significantly improve lipid compositions to prevent against CHD. There was no significant change both in fatty acid composition in platelet and ADP-induced platelet aggregation by GLA supplement to corn oil diet and by ALA in PO diet in young women.

• Molecules and Cells
• /
• v.19 no.2
• /
• pp.205-211
• /
• 2005

The Arg-Gly-Asp (RGD) sequence serves as the primary recognition site in extracellular matrix proteins, and peptides containing this sequence can mimic the biological activities of matrix proteins. We have initiated structure-function studies of two RGD containing peptides, RGD-5(AGGDD) and cyclic RGD-6(CARGDDC). Assays have shown that cyclic RGD-peptides inhibit platelet aggregation more efficiently than linear ones. NMR data revealed that RGD-5 and RGD-6 have entirely different conformation. RGD-5 has a linear extended structure and RGD-6 has a stable loop conformation. In RGD-5 the guanidinium group of Arg2 and the carboxyl group of Asp4 lie in parallel, whereas the side-chains of Arg3 and Asp5 of RGD-6 are located in different planes, supporting the idea that the stability of the cyclic form derives from the packing of the side chain of the Arg and Asp residues. The structural features of these peptides could provide a basis for designing new drugs against diseases related to platelet aggregation and as cancer antagonists.

• Toxicological Research
• /
• v.6 no.1
• /
• pp.109-119
• /
• 1990

Ro09-0198, a cyclic peptide isolated from culture filtrates of Streptoverticillium griseoverticillatum, induced lysis of erythrocytes. Ro-09-0198-induced hemolysis was temperature-dependent and the sensitivity of hemolysis differed greatly among animal species. Preincubation of the peptide with phosphatidylethanolamine reduced the hemolytic activity, whereas other phospholipids present in erythrocytes in nature had no effect. A study of the structural requirements on phosphatidylethanolamine necessary for interaction with the peptide indicates that Ro09-0198 recognizes strictly a particular chemical structure of phosphatidylethanolamine: dialkylphosphoethanolamine as well as 1-acylglycerophosphoethanolamine showed the same inhibitory effct on hemolysis induced by Ro09-0198 as diacylphosphatidyl-ethanolamine, whereas phosphoethanolamine gave no inhibitory effect. Neither phosphatidyl-N-monomethylethanolamine nor alkylphosphopropanolamine had an inhibitory effect. Proton resonances of the peptide were observed in dimethyl sulfoxide solution in the presence of 1-dodecanoyl-sn-glycerophosphoethanolamine. This peptide caused permeability increase and aggregation of liposomes containing phosphatidylethanolamine. A glycerol backbone and a primary amino group of phosphatidylethanolamine are necessary for interaction with Ro09-0198 to cause membrane damage. Ro09-0198 induced a selective permeability change on liposomes. Glucose and umbelliferyl phosphate were effluxed significantly, but sucrose was only slightly permeable and inulin could not be released. Platelet aggregation and serotonin release simultaneously induced by Ro09-0198. Addition of peptide to rat platelet, loaded with the fluorescent $Ca^{++}$ chelator quin-2, caused immediate rise in cytosolic free $Ca^{++}$ to liposomal membrane containing phosphatidylethanolamine was observed dose dependently.

• Journal of the Korean Ceramic Society
• /
• v.49 no.5
• /
• pp.438-441
• /
• 2012

Abalone shell is a high strength and light weighted ceramic composite material, which is composed of $CaCO_3$ platelet and protein. Microstructure of abalone shell has a matrix structure that is similar to the bricks and mortar. The technology inspired from nature which consumes low energy at low temperature is called bioinspired technology. In this study, to make high strength and light weighted ceramic composite materials using bioinspired technology, porous green body was prepared with $Al_2O_3$ platelet. PMMA was infiltrated into the porous green body, then warm pressed to eliminate pores present in the composite. The microstructure of the composite was observed with FESEM, and the mechanical/thermal properties were measured.

• Food Science and Biotechnology
• /
• v.18 no.6
• /
• pp.1423-1429
• /
• 2009

Rhizopus oryzae KSD-815 was isolated from nuruk that has been used to make Korean traditional wines. This study was performed to investigate the effect of cultures of R. oryzae KSD-815 on cardiovascular disorders and cancer metastasis. Firstly, these cultures were sequentially fractionationed with n-hexane (TAHe), ethylacetate (TAE), n-butanol (TAB), and $H_2O$ (TAW). The TAE inhibited the activity of angiotensin-converting enzyme (ACE) and TAB suppressed platelet aggregation in vitro. TAE and TAB inhibited cell motility of human breast cancer cells. Furthermore, TAW interrupted the formation of neovasculature and tube-like structure, and down-regulated the expression of angiogenic factors, basic fibroblast growth factor (bFGF), tumor necrosis factor-$\alpha$ (TNF-$\alpha$), and hypoxia-inducible factor-$1{\alpha}$ (HIF-$1{\alpha}$) in breast cancer cells. These results indicated that cultures of R. oryzae KSD-815 display the inhibitory activities on hypertension, platelet aggregation, and metastasis, and suggest that these cultures might be further probed for the purposes as therapeutic agents or dietary supplements.

• Journal of the Korean Ceramic Society
• /
• v.46 no.3
• /
• pp.288-294
• /
• 2009

The platelet AlO(OH) nano colloids were prepared by hydrothermal reaction of the $\gamma-Al_2O_3$ obtained with dehydration of $\gamma$-AlO(OH) and dilute $CH_3COOH$ solution. In hydrothermal reaction process, reversible reaction was accompanied between $\gamma-Al_2O_3$ and AlO(OH), and hydrothermal reaction temperature, hydrothermal reaction time and $CH_3COOH$ concentration had an effect on the crystal structure, surface chemical property, surface area, pore characteristics and crystal morphology of the AlO(OH) nano colloid particles. In this study, it was investigated to the hydrothermal reaction condition of the AlO(OH) nano colloid for using catalyst support, heat resisting agent, adsorbents, binder, polishing agent and coating agent. The crystal structure, surface area, pore volume and pore size of the platelet AlO(OH) nano colloids were investigated by XRD, TEM, TG/DTA, FT-IR and $N_2$ BET method in liquid nitrogen temperature.

• Journal of Biomedical Engineering Research
• /
• v.8 no.2
• /
• pp.199-204
• /
• 1987

ABA type block copolymers composed of r benzyle L-glutamate as the A component and poly(ethylene glycol) as the B components were obtained. Platelet adhesion on their sunfaces was investigated by a column elusion method to examine the effects of microdomain and secondary structure. The number of platelets adhered from whole blood and plasma rich platelet was smaller for the block copolymer systems than for the homopolymers. In the block copolymer system, the number of platelets adrered on their surfaces increased with increasing the content of PEG, that is, with decreasing of a-helix of block copolymers. A thick thrombus formation on the PBLG homopolymer was observed than block copolymer by scanning electron micrographs. The platelets adhesion increased with increasing the critical surface tension of the block copolymer.

• Journal of the Korean Vacuum Society
• /
• v.4 no.S2
• /
• pp.8-19
• /
• 1995

Ion beam enhanced deopsition(IBED) was adopted to synthesize biocompatible titanium oxide film. Structure characteristics of titanium oxide film were investigated by RBS, AES and XRD. The blood compatibility of the titanium oxide film was studied by measurements of blood clotting time and platelet adhesion. The results show that the anticoagulation property of titanium oxide film is improved significantly. The mechanism of anticoagulation of the titanium oxide film was discussed.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.34 no.9
• /
• pp.1320-1324
• /
• 2005

Soybean (Glycine max L.) is an increasingly important food source and functional food. Platelet aggregation plays an important role in thrombogenesis and atherosclerosis. Here, we studied the anti-platelet aggregating effects of solvent extracts from Korean soybean varieties and isoflauone derivatives. Nine Korean soybean varieties were extracted by solvents (methanol and buthanol and their extracts was investigated for the inhibition against tile aggregation of washed rabbit platelets induced by collagen or thrombin. Maximal inhibition of buthanol extracts against platelet aggregation induced by collagen was $95\%$ in Black-kong and Jinpum - kong. The potency of their inhibition was in the following order : Black > Jinpum > Bokwang > Hwangkum > Pureun > Malli > Danbaek > Danyeob > Jangsu - kong. The Black - kong only seemed to produce the maximal inhibition against platelet aggregation induced by thrombin. Total isoflavone content measured was Jinpum-kong ($1347.8{\mu}g/g$) and Black-kong ($918.7{\mu}g/g$). Maximal inhibition of isoflavone derivatives against platelet aggregation induced by collagen was $97\%$ in genistein. The potency of their inhibition was in the following order: genistein>daidzein>genistin. The isoflavone derivatives did not affect the platelet aggregation induced by thrombin. However, Black-kong cortex seemed to Produce the optimal inhibition against platelet aggregation induced by collagen. These results suggest that Black-kong and Jinpum-kong may be a good source for antiplatelet agents, and their antiplatelet effect be related to tile content and the chemical structure with the number of -OH group and the attached glycoside in the isoflavone derivative.

• Archives of Pharmacal Research
• /
• v.29 no.11
• /
• pp.952-956
• /
• 2006

A phytochemical investigation of stems from Salvadora persica resulted in the first isolation of four benzylamides from a natural source. The isolated compounds were identified as butanediamide, $N^{1},\;N^{4}$-bis(phenylmethyl)-2(S)-hydroxy-butanediamide (1), N-benzyl-2-phenylacetamide (2), N-benzylbenzamide (3) and benzylurea (4). The structure elucidation was accomplished using spectroscopic methods, especially 2D NMR and HREIMS. Compound 2 revealed a significant inhibitory effect on human collagen-induced platelet aggregation, and a moderate antibacterial activity against Escherichia coli.