• Asian-Australasian Journal of Animal Sciences
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• v.20 no.10
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• pp.1503-1509
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• 2007

Endothelin-1 (ET-1) is an important factor in regulation of cardiovascular tone in humans and mammals, but the biological function of ET-1 in the avian vascular system has not been determined. The purpose of this study was to characterize the role of endogenous ET-1 in the vascular system of poultry by investigating the effect of endothelin A receptor ($ET_AR$) antagonist BQ123 on the femoral artery pressure (FAP) and the pulmonary artery pressure (PAP) in broiler chickens. First, we found that plasma and lung homogenate ET-1 levels were both increased with age over the seven weeks life cyccle of broiler chickens. Second, 60 min after intravenous injection, BQ123 ($0.4{\mu}g\;kg^{-1}$ and $2.0{\mu}g\;kg^{-1}$, respectively) induced a significant reduction in FAP and PAP (p<0.05). Third, chronic infusion of BQ123 ($2.0{\mu}g\;kg^{-1}$ each time, two times a day) into abdominal cavities led to significant decrease in systolic pressure of the femoral (p<0.05) and pulmonary arteries (p<0.01) in broiler chickens at 7 and 14 days after treatment. Taken together, the $ET_AR$ antagonist BQ123 lead to a significant reduction of FAP and PAP, which suggests that endogenous ET-1 may be involved in the maintenance and regulation of systemic and pulmonary pressure in broiler chickens.

• Journal of Chest Surgery
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• v.33 no.1
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• pp.7-19
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• 2000

Background :To assess the accuracy of Electron-Beam Tomography(EBT) in following evaluation of the pulmonary vascular system after a shunt operation in the cyanotic con-genital heart disease with pulmonary stenosis or pulmonary atresia. Material and Method : Sixteen patients(M:F=11:5) who received Blalock-Taussig(n=8) bidirectional cavo-pulmonary shunt(n=10) and unifocalization (n=2) were ncluded in the study. We evaluated the patency of the shunt the morphology of intrapericardial and hilar pulmonary arteries(PA) peripheral pulmonary vascularity by background lung attenuation and the abundance of arterial & venous collateral. Angiography(n=12) and echocardiography(n=20) were used as the gold standard for the comparison of EBT results. Result: EBT was consistent with angiogram/ echo in 100% of the evaluation for the patency of the shunt and in 12(by angiogram 100%) and 19(by echo 95%) for the detection the hypoplasia stenosis or interruption of central PA In measuring of PA EBT and angiogram corrlated(r=0.91) better than EBT-echo(r=0.88) or echo-angiogram(r=0.72) Abundant systemic arterial collateral were noted in 4 and venous collateral in 3 cases. In evaluating the peripheral pulmonary vascularity the homogenous and normal-ranged lung attenuation(m=6) decreased but homo-genous attenuation(n=1) segment-by-sgment heterogeneous attenuation(n=3) homogenous but asymmetrical attenuation(n=3) segment-by-segment heterogeneous attenuation(n=3) homogenous but asymmetrical attenuation(n=3) and venous congestion(n=2) were observed nd 12 of them were compatible with the blood flow pattern revealed by cardiac catheterization. Conclusion: EBT was accurate in the integrated evaluation of the pulmonary vascular system after the shunt including the patency of the shunt operaion the morphology and dimension of the central and hilar PAs and the loco-regional pulmonary flow in the lung parenchyma. It suggests the useful information about the need of secondary shunt operation the proper timing time for total repair and the need of interventional procedure prior to total repair.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.05a
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• pp.622-624
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• 2015

Tumor hypoxia caused by the unique characteristics of solid tumor sites such as lowered vascular density, irregular vasculature, longitudinal oxygen gradient, and unbalanced oxygen consumption has decreased therapeutic efficacy in several clinical trials such as radiation, chemotherapy, and surgery. Hence, tumor oxygenation studies at microvascular levels are important to provide better understanding of the complexity of microvasculature oxygen transport and exchange with tissue. However, polarographic microelectodes, was employed to measure $pO_2$ at the microvasculature level, but it is difficult to perform and does not provide significant spatial and temporal information of oxygen delivery. In this research, we introduce the hyperspectral imaging system able to provide a wide range of vascular characteristics by spatial maps on hemoglobin saturation information for better understanding of the relationship between blood oxygen delivery, hypervascularity, aberrant angiogenesis at microvasculature levels during tumor growth.

• Journal of Chest Surgery
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• v.43 no.3
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• pp.316-319
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• 2010

An aneurysm is a focal, localized dilatation of a blood vessel. This term is most commonly applied to dilatation of arteries. However, dilatation can occur in any part of the vascular system. Primary true aneurysm of the superficial venous system that contains all the vascular layers is known to be very rare. We report here on surgically treating a case of primary true aneurysm on the dorsalis pedis vein and we briefly review the related literature.

• The Korean Journal of Physiology and Pharmacology
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• v.21 no.6
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• pp.643-650
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• 2017

Vascular dementia (VaD) is a group of heterogeneous diseases with the common feature of cerebral hypoperfusion. To identify key factors contributing to VaD pathophysiology, we performed a detailed comparison of Wistar and Sprague-Dawley (SD) rats subjected to permanent bilateral common carotid artery occlusion (BCCAo). Eight-week old male Wistar and SD rats underwent BCCAo, followed by a reference memory test using a five-radial arm maze with tactile cues. Continuous monitoring of cerebral blood flow (CBF) was performed with a laser Doppler perfusion imaging (LDPI) system. A separate cohort of animals was sacrificed for evaluation of the brain vasculature and white matter damage after BCCAo. We found reference memory impairment in Wistar rats, but not in SD rats. Moreover, our LDPI system revealed that Wistar rats had significant hypoperfusion in the brain region supplied by the posterior cerebral artery (PCA). Furthermore, Wistar rats showed more profound CBF reduction in the forebrain region than did SD rats. Post-mortem analysis of brain vasculature demonstrated greater PCA plasticity at all time points after BCCAo in Wistar rats. Finally, we confirmed white matter rarefaction that was only observed in Wistar rats. Our studies show a comprehensive and dynamic CBF status after BCCAo in Wistar rats in addition to severe PCA dolichoectasia, which correlated well with white matter lesion and memory decline.

• Genomics & Informatics
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• v.2 no.1
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• pp.36-44
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• 2004

Astrocytes play supportive roles for neurons in the brain. Recently, they have been accepted to have various functions in the vascular system as well as in the nervous system. We investigated the differential gene expression in rat astrocytes according to the oxygen tension, which is a crucial factor for angiogenesis. A cDNA microarray was performed to find the genes whose expression was sensitive to oxygen tension. We found 26 genes in the astrocyte were found and classified into 4 groups. In order to show the genes' relevancy to angiogenesis, seven of the 26 genes were investigated to see whether they have capabilities of interaction with angiogenesis­related factors in AngioDB. Through this investigation, we found interactions of three proteins with angiogenesis-related factors. These genes were further investigated with a new focus on the vascular endothelial growth factor (VEGF) expression in an astrocyte based on our hypothesis that astrocytes can have effects on endothelial angiogenesis via the release of VEGF. Collectively, we identified several genes whose expressions were dependent on the oxygen concentration of the astrocyte. Furthermore, the relevancy of astrocytes to angiogenesis was investigated using preexisting information of AngioDB, and suggested a possible signaling pathway for VEGF expression in the aspects of brain endothelial angiogenesis by astrocytes.

• The Korean Journal of Physiology and Pharmacology
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• v.15 no.5
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• pp.273-277
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• 2011

Nitric oxide (NO) and atrial natriuretic peptide (ANP) may induce vascular relaxation by increasing the production of cyclic guanosine monophosphate (cGMP), an important mediator of vascular tone during sepsis. This study aimed to determine whether regulation of NO and the ANP system is altered in lipopolysaccharide (LPS)-induced kidney injury. LPS (10 $mg{\cdot}kg^{-1}$) was injected in the tail veins of male Sprague-Dawley rats; 12 hours later, the kidneys were removed. Protein expression of NO synthase (NOS) and neutral endopeptidase (NEP) was determined by semiquantitative immuno-blotting. As an index of synthesis of NO, its stable metabolites (nitrite/nitrate, NOx) were measured using colorimetric assays. mRNA expression of the ANP system was determined by real-time polymerase chain reaction. To determine the activity of guanylyl cyclase (GC), the amount of cGMP generated in response to sodium nitroprusside (SNP) and ANP was calculated. Creatinine clearance decreased and fractional excretion of sodium increased in LPS-treated rats compared with the controls. Inducible NOS protein expression increased in LPS-treated rats, while that of endothelial NOS, neuronal NOS, and NEP remained unchanged. Additionally, urinary and plasma NOx levels increased in LPS-treated rats. SNP-stimulated GC activity remained unchanged in the glomerulus and papilla in the LPS-treated rats. mRNA expression of natriuretic peptide receptor (NPR)-C decreased in LPS-treated rats, while that of ANP and NPR-A did not change. ANP-stimulated GC activity reduced in the glomerulus and papilla. In conclusion, enhancement of the NO/cGMP pathway and decrease in ANP clearance were found play a role in the pathogenesis of LPS-induced kidney injury.

• Korean Journal of Plant Taxonomy
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• v.46 no.4
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• pp.392-404
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• 2016

The anatomical characters of the 19 taxa of Korean Juncus were reviewed in order to examine their significance in taxonomy. Cross-section analyses were conducted on the stem, leaf, and capsule. Descriptions, line drawings, tables, and a species key of Korean Juncus are provided for species identification based on anatomical characters. The results of this study showed that the arrangements of the vascular bundle, fiber, and air-space structure in the stems as well as the arrangements of the vascular bundle and parenchyma in the leaves and the development of placenta in capsules are the key characters to be used when classifying each species of Juncus. It was revealed that the studied anatomical features were more useful for identification at the subgenera and section levels than at the species level. Therefore, these anatomical characters used in conjunction with external morphological features will make a valuable contribution to establishing a natural classification system for Juncus.

• Archives of Plastic Surgery
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• v.36 no.4
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• pp.380-384
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• 2009

Purpose: Autologous vessels remain the gold standard for vascular grafts in microanastomoses. However, they are sometimes unavailable and have a limited long - term patency. Synthetic vessels have high success rates in large - diameter reconstructions but failed when used as small - diameter grafts due to graft occlusion. It has been proved that endothelial cell seeding improves prosthesis performance and long - term patency. Among polyurethane, PET and ePTFE, polyurethane has the best affinity to endothelial cells and mechanical properties closest to human vessels. We examined the ability of endothelial cells to attach to a polyurethane graft manufactured by the electrospinning method. Methods: Endothelial cells, which were cultured from porcine internal jugular veins, were attached to polyurethane grafts with an internal diameter of 3 mm. The same cells were attached to allogeneic decellularized porcine internal carotid artery grafts as controls. Both of the 10 mm - long grafts were exposed to endothelial cells in a well for 1 hour. Each well contained $2{\times}10^5$ endothelial cells. The graft materials were rotated through 90 degrees every 15 minutes in order to minimize the effect of gravity. The extent of cell attachment was examined with the MTT assay. Results: The MTT assay showed good incorporation of endothelial cells into both grafts. For the evaluation of affinity, the number of attached cells was counted at 10 fields of microscopic examination with ${\times}40$ magnification. Endothelial cells adhered more to polyurethane grafts (mean, $127.4{\pm}6.2cells$) compared to porcine artery grafts (mean $45.8{\pm}5.1cells$)(p<0.05,Mann - Whitney test). Conclusion: In this study, we attached porcine endothelial cells to polyurethane grafts, manufactured by electrospinning. The grafts exhibited a better affinity to endothelial cells than allogeneic decellularized porcine internal carotid artery grafts. It is suggested that the time required for endothelial cells to attach to decellulized artery grafts may be longer than that which is required for attachment to polyurethane grafts.

• Journal of Digital Convergence
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• v.12 no.3
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• pp.367-375
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• 2014

In this thesis we observe microvascular structure in mice by using micro-computed tomography (CT), which is high-resolution X-ray imaging equipment that can acquire Real-time dynamic image, and it aims to investigate the usefulness of micro-CT developed by Institute for Radiological Imaging Science Wonkwang University School of Medicine. After acquiring the systemic images of rats, contrast-enhanced 3D images of vascular structures could be acquired by using Maximum Intensity Projection (MIP) and Volume Rending Technique (VRT), This was divided into each vascular system of head, abdomen and heart and systemic vascular system.