• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 학술대회
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• pp.186-196
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• 2008

The dependence of the rheological properties of blood on shape, aggregation, and deformability of red blood cells (RBCs) has been investigated using hybrid systems by coupling fluid with solid models. We present a simple approach for simulating blood as a multi-component fluid, in which RBCs are modeled as droplets of acquired biconcave shape. We used lattice Boltzmann method (LBM) due to its excellent numerical stability as a simulation tool. The model enables us to control the droplet static shape by imposing non-isotropic surface tension force on the interface between the two components. The use of the proposed non-isotropic surface tension method is justified by the Norris hypothesis. This hypothesis states that the shape of the RBC is due to a non-uniform interfacial surface tension force acting on the RBC periphery. This force is caused by the unbalanced distribution of the lipid molecules on the surface of the RBC. We also used the same concept to investigate the dynamic shape change of the RBC while flowing through the microvasculature, and to explore the physics of the Fahraeus, and the Fahraeus-Lindqvist effects.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년 추계학술대회논문집
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• pp.186-196
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• 2008

The dependence of the rheological properties of blood on shape, aggregation, and deformability of red blood cells (RBCs) has been investigated using hybrid systems by coupling fluid with solid models. We present a simple approach for simulating blood as a multi-component fluid, in which RBCs are modeled as droplets of acquired biconcave shape. We used lattice Boltzmann method (LBM) due to its excellent numerical stability as a simulation tool. The model enables us to control the droplet static shape by imposing non-isotropic surface tension force on the interface between the two components. The use of the proposed non-isotropic surface tension method is justified by the Norris hypothesis. This hypothesis states that the shape of the RBC is due to a non-uniform interfacial surface tension force acting on the RBC periphery. This force is caused by the unbalanced distribution of the lipid molecules on the surface of the RBC. We also used the same concept to investigate the dynamic shape change of the RBC while flowing through the microvasculature, and to explore the physics of the Fahraeus, and the Fahraeus-Lindqvist effects.

• 순환기질환의공학회:학술대회논문집
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• 순환기질환의공학회 2005년도 제5회 학술대회 초록집
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• pp.27-28
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• 2005

• 순환기질환의공학회:학술대회논문집
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• 순환기질환의공학회 2005년도 제5회 학술대회 초록집
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• pp.29-30
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• 2005

• 순환기질환의공학회:학술대회논문집
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• 순환기질환의공학회 2006년도 제6회 학술대회
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• pp.15-16
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• 2006

• Toxicological Research
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• 제8권1호
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• pp.109-118
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• 1992

Streptozotocin (STZ) is a naturally occurring nitrosoamide used extensively to produce diabetes in experimental animals. Since streptozotocin reportedly decrease deformability of red blood cells (RBC), we sought to investigate its potential toxicity at RBC. In addition to elevation blood glucose, 100mg/kg iv streptozotocin caused significant RBC hemolysis in female Sprague-Dawley at 48 hrs post treatment. Streptozotocin induced hemolysis was found to be dose and time-dependent` complete hemolysis required a relatively high streptozotocin concentration (500 mM, 4 hrs incubation), which is much more than in vivo dose.

• 대한한의학회지
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• 제23권2호
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• pp.164-179
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• 2002

Object: Death rate due to hypertension, atherosclerosis, ischemic heart disease and cerebral infarction induced by Westernized diet and increased average life span is on the rise. Decrease in blood circulation, activation of thrombus generation and intravascular lipid accumulation, cited as the principal causes of the above mentioned diseases in recent studies, result in circulatory disturbance and blood vessel obstruction leading to ischemic cell death of heart, brain and peripheral vessels. Method: We investigated the biochemical changes in microvascular permeability, aggregation of platelet and the intravascular lipid accumulation in induced-diabetic rat using Streptozotocin. We also studied the effects of Woohwangcheongsirn-won after oral administration on blood circulation, platelet function and lipid metabolism. The results are as follows: I. Woohwangcheongsim-won increased blood circulation in microvessels. 2. Woohwangcheongsim-won increased the reduced erythrocyte deformability in diabetes. 3. Woohwangcheongsim-won induced the reduction of contents of 2, 3-DPG, but failed to affect the reduced contents of ATP in erythrocyte in diabetes. 4. Woohwangcheongsim-won reduced the activity of Ca/sup 2+/-ATPase in the membrane of erythrocyte. 5. Woohwangcheongsim-won reduced the platelet aggregation evoked by platelet agglutinin factor. 6. Woohwangcheongsim-won reduced the production of platelet-derived granules. 7. Woohwangcheongsim-won reduced the production of metabolites of arachidonic acid in diabetes, and also reduced the production of increased thromboxane B2. 8. Woohwangcheongsim-won reduced the synthesis of oxidized LDL-cholesterol. In conclusion, Woohwangcheongsim-won enhanced blood circulation in microvesseles, erythrocyte deformability and inhibited the increased platelet aggregation and the synthesis of oxidized LDL-cholesterol in diabetes. Therefore Woohwangcheongsim-won is believed to positively affect blood circulation (J Korean Oriental Med 2002;23(2):164-179)

• Korea-Australia Rheology Journal
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• 제21권3호
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• pp.155-160
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• 2009

Micropore filtration of dilute red blood cell (RBC) suspensions is a widely known method for determining red blood cell deformability. Use of this method for cells from various laboratory animal species does require considering the effects of the cell size to pore size ratio and of suspension hematocrit. In general, previous animal studies have utilized 5% hematocrit suspensions and five micron pores, and thus conditions similar to human clinical laboratory practice. However, when used for repeated sampling from small laboratory animals or for parallel multiple samples from different sites in large laboratory animals, the volume of blood sampled and hence the hematocrit of the test suspension may be limited. Our results indicate that hematocrit levels yielding stable values of RBC pore transit time are pore size and species specific: three micron pores = $2{\sim}5%$ for dog and $3{\sim}5%$ for rat; five micron pores $3{\sim}5%$ for dog and $1{\sim}5%$ for rat. An analytical approach using a common expression for calculating transit time is useful for determining the sensitivity of this time to hematocrit alterations and hence to indicate hematocrit levels that may be problematic.

• Biomolecules & Therapeutics
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• 제9권1호
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• pp.1-6
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• 2001

Sa-Mul-Tang (Si-Wu-Tang, SMT), a kind of Chinese medicine, has been used for the hemato-deficient disease for hundreds of years. In this work, investigations on the anti-anemic activity of an aqueous extract of SMT were undertaken in order to find the pharmacological basis for the ethnomedical use of the formulation. Three kinds of Angelicase species, such as Angelica sinensis, Angelica acutiloba, and Angelica gigas, were used for preparing the water extracts of SMT. Anemic model rats were induced by the treatment of phenylhydrazine (40 mg/kg/day, i.p.) for 4 days. After the treatment of phenylhydrazine, rats were divided into several groups for their different treatment of three kinds of SMT. Red blood cell (RBC), hemoglobin (Hg), and hematocrit (Hct) were determined on the day 0, 3, 6, 10, 14 after the treatment of SMTs and erythrocytes deformabilities were also determined at the end of experiments. Oral administration of SMT (1g/kg/day) for 14 days did not ameliorate drug-induced anemic states evaluated by RBC counts, Hg contents, and Hct values. However, the erythrocyte deformabilities were improved in phenylhydrazine-treated group by the administragest that SMTs (p<0.05). Especially, these effects were high in the Angelica acutiloba group. These results suggest that SMTs have an ameliorative effect on blood rheology related to the blood stasis syndrome in oriental diagnostics not on the blood deficient states related to the anemic syndrome.

• 대한한방내과학회지
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• 제21권5호
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• pp.829-837
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• 2000

Purpose : To investigate the inhibitory effect of BHE on platelet aggregation and erythrocyte deformability, we performed following experiments. Methods : Concentrated Boyanghwanotang (BHE) was fed to rats for 10days. High dose group was treated with $500{\beta}{\partial}/kg$ and low dose group with $500{\beta}{\partial}/kg$. Results : BHE enhanced the blood filtration rate, reduced the platelet aggregability, inhibited granule release from collagen-stimulated platelet, the prostaglandin syn-thesis in platelet and enhanced erythrocyte deformability. Conclusion : BHE should inhibit thrombos formation due to platlete hyperaggregabili-ty and reduction of erythrocyte deformabi-lity.