• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.11
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• pp.985-990
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• 2013

An arteriovenous fistula is artificially produced using a graft for hemodialysis in patients. In an arteriovenous graft (AVG), the angle of its arterial or venous anastomosis play an important role in producing flows inside blood vessels, through which a stenosis may occur. Most studies thus far have focused on CFD results. In this study, a PIV technique is used to analyze the hemodynamic characteristics at the arterial or venous anastomosis of an AVG having an angle of $30^{\circ}C$. For flow dynamic similarity, the Reynolds number is set to be the same for real and simulated flows. A PIV experiment is performed with a control valve in the arterial part. In conclusion, the recirculation flow appeared in the bifurcation area and the total blood velocity changed according to the extent of valve opening.

• IMMUNE NETWORK
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• v.7 no.3
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• pp.117-123
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• 2007

Background: This study was designed to investigate the role of the hepatocyte growth factor (HGF) with regards to differentiation of somatic stem cells originating from the human umbilical cord blood (UCB) into hepatic lineage cells in vitro culture system. Methods: Mononuclear cells from UCB were cultured with and without HGF based on the fibroblast growth factor (FGF)-1, FGF-2, and stem cell factor. The cultured cells were confirmed by immunofluorescent staining analysis with albumin (ALB), cytokeratin-19 (CK-19), and proliferating cell nuclear antigen (PCNA) MoAb. ALB and CK-18 mRNA were also evaluated by reverse transcription-polymerase chain reaction. In order to observe changes in proliferating capacity with respect to the cultured period, CFSE with affinity to proliferating cells were tagged and later underwent flow cytometry. Results: In the HGF-treated group, cultured cells had a large oval shaped appearance with adherent, but easily detachable characteristics. In the HGF-non treated group, these cells were spindle-shaped with strong adherent characteristics. Expressions of ALB and CK-19 were evident in HGF-treated group compared to non-expression of those in to HGF-non treated group. Dual immunostaining analysis of the ALB producing cells showed presence of PCNA in their nuclei, and ALB and CK-18 mRNA were detected on the 21st day of cultured cells in the HGF-treated group. Conclusion: Our findings suggest that HGF has a pivotal role in differentiating somatic stem cells of human UCB into hepatic lineage cells in vitro.

• Proceedings of the KSME Conference
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• 2001.06e
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• pp.560-565
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• 2001

The objective of the present study is to investigate the characteristics for flow and wall shear stress in the aneurysm which is a local dilatation of the blood vessel. The numerical simulation using the commercial software for the laminar and steady flow were carried out over the diameter ratios(ratio of maximum diameter of aneurysm to the diameter of blood vessel) ranging from 1.5 to 2.5 and Reynolds number ranging from 900 to 1800. It was shown that a recirculating vortex occupied the entire bulge with its core located closer to the distal end of the bulge and the strength of vortex increased with increase of the Reynolds number and diameter ratio. Especially, for the Reynolds number of 1800 and diameter ratio of 2.5, the very weak secondary recirculating flow was produced at the left upper of the aneurysm. The position of a maximum wall shear stress was the distal end of the aneurysm(z=18mm) regardless of the Reynolds number and diameter ratios. But the maximum values of the wall shear stress increased in proportion to the increase of Reynolds number and diameter ratio.

• Korea-Australia Rheology Journal
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• v.18 no.2
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• pp.51-65
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• 2006

Of concern in the present theoretical investigation is the study of blood flow and convection-dominated diffusion processes in a model bifurcated artery under stenotic conditions. The geometry of the bifurcated arterial segment having constrictions in both the parent and its daughter arterial lumen frequently appearing in the diseased arteries causing malfunction of the cardiovascular system, is constructed mathematically with the introduction of suitable curvatures at the lateral junction and the flow divider. The streaming blood contained in the bifurcated artery is treated to be Newtonian. The flow dynamical analysis applies the two-dimensional unsteady incompressible nonlinear Wavier-Stokes equations for Newtonian fluid while the mass transport phenomenon is governed by the convection diffusion equation. The motion of the arterial wall and its effect on local fluid mechanics is, however, not ruled out from the present model. The main objective of this study is to demonstrate the effects of constricted flow characteristics and the wall motion on the wall shear stress, the concentration profile and on the mass transfer. The ultimate numerical solutions of the coupled flow and diffusion processes following a radial coordinate transformation are based on an appropriate finite difference technique which attain appreciable stability in both the flow phenomena and the convection-dominated diffusion processes.

• Journal of Environmental Science International
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• v.22 no.12
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• pp.1615-1624
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• 2013

The aims of this study were to investigate and confirm the occurrence and distribution patterns of blood lipid lower agents (BLLAs) in Nakdong river basin (mainstream and its tributaries). 4 (atorvastatin, lovastatin, mevastatin and simvastatin) out of 5 statins and 2 (clofibric acid and zemfibrozil) out of 3 fibrates were detected in 29 sampling sites and simvastatin (>50%) was predominant compound followed by atorvastatin, lovastatin and clofibric acid. The total concentration levels of BLLAs on April, August and November 2009 in surface water samples ranged from ND~25.7 ng/L, ND~18.8 and ND to 38.8 ng/L, respectively. The highest concentration level of BLLAs in the mainstream and tributaries in Nakdong river were Goryeong and Jincheon-cheon, respectively. The sewage treatment plants (STPs) along the river affect the BLLAs levels in river and the BLLAs levels decreased with downstream because of dilution effects.

• YAKHAK HOEJI
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• v.54 no.4
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• pp.300-308
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• 2010

Adrenoceptor has been considered to be an important target in psychiatric disorders. Based on x-ray structures of bovine rhodopsin, we established homology model of ${\alpha}_{2c}$-adrenoceptor (ADA2C_rat) and then analyzed docking from binding model of receptor-ligand complex with high-active compound No.29 in tricyclic isoxazole analogues (1-30). We observed that the N (1.907 $\AA$) and O (1.712 $\AA$) atoms of isoxazole ring on the docked ligand (No.29) formed H-bonding interaction with O-H of Ser5.32 and carmeron phenyl ring centroid of tricyclic isoxazole formed $\pi-\pi$ interaction at 3.342 $\AA$ distance with phenyl ring centroid of Phe6.52. According to predictions of blood-brain distribution (logBB) through penetration of blood-brain barrie (BBB) and polar surface area (PSA) of the ligands, the high-active compound No.29 has values of logBB=-0.203, PSA=67.50, respectively. These results suggest that the high-active compound No.29 is a novel anti-depressant with the characteristics such as dopamine and serotonin.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.18
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• pp.8197-8201
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• 2016

Background: To investigate the expression of the fragile histidine triad (FHIT) gene in acute lymphoblastic leukemia and its clinical significance. Materials and Methods: The level of expressed FHIT mRNA in peripheral blood from 50 patients with acute lymphoblastic leukemia (ALL) and in 50 peripheral blood samples from healthy volunteers was measured via RT-PCR. Correlation analyses between FHIT gene expression and clinical characteristics (gender, age, white blood count, immunophenotype of acute lymphoblastic leukemia and percentage of blast cells) of the patients were performed. Results: The FHIT gene was expressed at $2.49{\pm}7.37$ of ALL patients against $14.4{\pm}17.9$ in the healthy volunteers. The difference in the expression levels between ALL patients and healthy volunteers was statistically significant. The rate of gene expression did not significantly vary with immunophenotype subtypes. Gene expression was also found to be correlated with increase of total leukocyte and decrease in platelets, but not with age, gender, immunophenotyping or percentage of blast cells. Conclusions: FHIT gene expression is low in acute lymphoblastic leukemia and could be a useful marker to monitor minimal residual disease. This gene is also a candidate target for the immunotherapy of acute lymphoblastic leukemia.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.8
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• pp.4009-4011
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• 2016

Background: Classical Hodgkin's lymphoma (cHL) is a B-cell lymphoid neoplasm characterized by a distinctive biological behavior with potentially curable disease characteristics. It is an uncommon hematological malignancy which primarily affects younger individuals. The rationale of this study was to determine its clinico-hematological profile along with stage stratification in Pakistani patients. Materials and Methods: In this descriptive study, adult patients with Hodgkin's lymphoma were enrolled from January 2010 to December 2014. Results: Sixty two histopathologically confirmed cases of cHL were identified. There were 42 males and 20 females, with a male to female ratio of 2: 1. The mean age was $29.7{\pm}13.8$ years with the median age of 30 years. B symptoms were present in 72.5% of patients. Histopathologically, the mixed cellularity type constituted 62.9% of cases, followed by nodular sclerosis in 25.8%, lymphocyte predominant in 9.6% and lymphocyte depleted in 1.6%. Stages I and II were present in 43.5% of patients at disease presentation, with 56.4% in stages III and IV. Conclusions: Our analysis shows that clinico-pathological features of Hodgkin's lymphoma in Pakistan are comparable to published data. Mixed cellularity is the commonest histological variant and advanced stage at presentation are common findings in our patients.

• Korea-Australia Rheology Journal
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• v.16 no.2
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• pp.101-108
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• 2004

The hemodynamics behavior of the blood flow is influenced by the presence of the arterial stenosis. If the stenosis is present in an artery, normal blood flow is disturbed. In the present study, the characteristics of pulsatile flow in the blood vessel with stenosis are investigated by the finite volume method. For the validation of numerical model, the computation results are compared with the experimental ones of Ojha et al. in the case of 45％ stenosis with a trapezoidal profile. Comparisons between the measured and the computed velocity profiles are favorable to our solutions. Finally, the effects of stenosis severity and wall shear stress are discussed in the present computational analysis. It can be seen, where the non-dimensional peak velocity is displayed for all the stenosis models at a given severity of stenosis, that it is exponentially increased. Although the stenosis and the boundary conditions are all symmetric, the asymmetric flow can be detected in the more than 57％ stenosis. The instability by a three-dimensional symmetry-breaking leads to the asymmetric separation and the intense swirling motion downstream of the stenosis.

• Journal of Korean Biological Nursing Science
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• v.4 no.2
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• pp.51-58
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• 2002

The purpose of this study was to identify clinical characteristics of type 2 diabetic patients with hypertension. The subjects were 209 type 2 diabetic patients who visited at the endocrine center at Kangnam St. Mary's Hospital of Catholic University in Seoul from beginning of March through the end of April in 2001. The patient's clinical laboratory data were assessed at medical record review. The data were analyzed using for t-test, $x^2$ test. The results were as follows: 1) There were no significant differences in age, body mass index, sex, family history of diabetes and oral hypoglycemic agents between hypertensive group and normotensive group, However, percentage of patients receiving insulin treatment was higher significantly in the hypertensive group. 2) Creatinine and microalbuminuria levels were higher significantly in the hypertensive group. However, fasting blood glucose levels were lower significantly in the hypertensive group. There were no significant differences in $HbA_1c$, 2-hour postprandial blood glucose, total cholesterol, triglyceride, high density lipoprotein cholesterol, lipoprotein(a) and blood urea nitrogen between two groups. Our present study supports that Creatinine and microalbuminuria levels were higher significantly in the hypertensive group.