• The Journal of Korean Academy of Prosthodontics
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• v.9 no.1
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• pp.53-57
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• 1969

Trauma from occlusion causes apparent changes in the blood vessels of the periodontal ligament. The initial response is primarily mechanical, due to compression, and secondarily characterized by necrotic changes. Recently, many investigators are concerned with vascular changes in relation to the loss of the alveolar bone. Author observed vascular changes of the periodontium in the experimental trauma from occlusion on rats. The results were observed as follows.: 1) There were no remarkable changes in the gingiva. 2) The blood vessels that normally occupied a position closer to the bone surface showed a displace-ment toward the cemental surface due to trauma from occlusion. 3) There were no appreciable changes of the alveolar bone in the initial period of trauma from occlusion, whereas there was excessive resorption of the alveolar bone in the long range.

• Physical Therapy Rehabilitation Science
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• v.2 no.2
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• pp.63-69
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• 2013

Objective: To assess the effect of vitamin D administration on the skin blood flow response to occlusion and heat. Design: Cross-sectional study. Methods: Twenty age matched subjects; 10 who had diabetes and 10 who were controls were administered 4,000 IU of vitamin D3 for 3 weeks at breakfast. The function of the endothelial cells was evaluated in 2 ways; first, the response to 4 minutes of vascular occlusion of the skin was measured with a laser Doppler flow meter. Second, the skin blood flow response to local heat at 42 degrees C for 6 minutes was examined. Results: The results of the experiments showed that the blood flow response to heat was reduced after 3 weeks administration of vitamin D in the subjects with diabetes and in the control subjects (p<0.05). The response to occlusion was not significantly different within each group before and after vitamin D administration, but the group with diabetes had a significantly lower blood flow response to occlusion than did the controls (p<0.05). Conclusions: Acute doses of vitamin D may impair nitric oxide production and reduce blood flow to tissue during stressors in people with diabetes.

• Physical Therapy Rehabilitation Science
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• v.1 no.1
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• pp.6-12
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• 2012

Objective: Coenzyme (CoQ10) is an enzymatic co factor used in normal cellular metabolism. Recent evidence shows that in people with heart disease it can reverse endothelial cell damage in the blood vessels. It is also a potent antioxidant. Design: One group pretest-posttest design. Methods: In the present study, endothelial function was evaluated using the response to occlusion and heat before and 2 weeks after administration of CoQ10, 300 mg/day. Thirty Eight subjects, who are physical therapy students, participated in a series of experiments to see if taking 300 mg of CoQ10 daily for 2 weeks would impact resting blood flow in the forearm skin and the blood flow response to 4 minutes of vascular occlusion and the response to local heat ($42^{\circ}C$) for 6 minutes. Results: The results showed that, for this population, there was no difference in the response to heat. However, the response to occlusion was improved after administration of CoQ10. Conclusions: It would appear that in a young population CoQ10 has no effect on the nitric oxide vasodilator pathway in skin but does influence other vasodilator pathways.

• Journal of Ginseng Research
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• v.46 no.5
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• pp.683-689
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• 2022

Background: Since ginsenosides exert an anti-thrombotic activity, blood flow-improving effects of DK-MGAR101, an extract of mountain ginseng adventitious roots (MGAR) containing various ginsenosides, were investigated in comparison with an extract of Korean Red Ginseng (ERG). Methods: In Sprague-Dawley rats orally administered with DK-MGAR101 or ERG, oxidative carotid arterial thrombosis was induced with FeCl₃ (35%), and their blood flow and occlusion time were measured. To elucidate underlying mechanisms, the cytoprotective activities on rat aortic endothelial cells (RAOECs) exposed to hydrogen peroxide (H₂O₂) were confirmed. In addition, the inhibitory activities of DK-MGAR101 and ERG on agonist-induced platelet aggregation, thromboxane B₂ production, and ATP granule release from stimulated platelets as well as blood coagulation were analyzed. Results: DK-MGAR101 containing high concentrations of Rb1, Rg1, Rg3, Rg5, and Rk1 ginsenosides (55.07 mg/g) was more effective than ERG (ginsenosides 8.45 mg/g) in protecting RAOECs against H₂O₂ cytotoxicity. DK-MGAR101 was superior to ERG not only in suppressing platelet aggregation, thromboxane B₂ production, and granule release, but also in delaying blood coagulation, FeCl₃-induced arterial occlusion, and thrombus formation. Conclusions: The results indicate that DK-MGAR101 prevents blood vessel occlusion by suppressing platelet aggregation, thrombosis, and blood coagulation, in addition to endothelial cell injury.

• Journal of Chest Surgery
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• v.54 no.5
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• pp.377-382
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• 2021

Background: Subclavian vein (SV) catheterization is a method for the delivery of fluids, drugs, and blood products, venous blood sampling, and central vein pressure monitoring in cardiac surgery. Catheter occlusion is a serious complication of SV catheterization during cardiac surgery, especially after sternal retractor expansion. Methods: In this observational study, 303 patients who had successful right infraclavicular SV catheterization from September 2019 to April 2020 were enrolled to determine the incidence of catheter occlusion. After catheterization, the lumens of all catheters were checked for the ability to infuse and withdraw blood from the catheter before and after sternal retractor expansion. The patients' characteristics, cannulation approach, on-pump or off-pump technique, occlusion of the catheter and its lumens, and any associated complications were recorded. The data were analyzed using IBM SPSS ver. 22.0 (IBM Corp., Armonk, NY, USA). Results: Of the 303 patients studied, 205 were male (67.7%) and 98 were female (32.3%). Catheter occlusion occurred in 11 patients with on-pump cardiopulmonary bypass (CPB) (227 patients) and 4 patients with off-pump CPB (76 patients) (p=0.863). The incidence of catheter occlusion was 4.95% (15 of 303 patients) with no cases of simultaneous 3-lumen occlusion in a catheter. The most commonly occluded lumen was the distal lumen (57.92%). Simultaneous 2-lumen occlusion occurred in 4 patients. Catheter occlusion was found in 3 of 13 malpositioned catheters (23.07%). Conclusion: The current study showed that malpositioning of the catheter tip was a risk factor for catheter occlusion and that the distal lumen of a triple-lumen catheter was the most commonly occluded lumen.

• Journal of Chest Surgery
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• v.25 no.2
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• pp.200-204
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• 1992

A 63 year old male had suffered from hypertension and angina pectoris for 4 years, On physical examination, blood pressure was 150/110 mmHg with medication of antihypertensive drugs. Aortogram showed the stenosis of the left renal artery, the complete occlusion of the right renal artery, and atherosclerotic change of abdominal aorta. Blood urea nitrogen was 25 mg/dl, serum creatinine was 1.2 mg/dl, and renin activity in peripheral blood was 8.7 ng /ml /hour, The stenosis of left renal artery and the complete occlusion of right renal artery should have produced the renovascular hypertension Bilateral aorto-renal bypasses with saphenous grafts were done for treatment of ren-ovascular hypertension Postoperatively, blood pressure was normalized with only small dosage of antihypertensive drugs.

• Journal of Veterinary Clinics
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• v.33 no.1
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• pp.10-15
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• 2016

The purpose of this study was to establish reproducible ischemic infarction model using allogenic blood clot in beagle dogs and identify induced ischemic lesion after middle cerebral artery occlusion using magnetic resonance imaging (MRI) and histopathologic findings. Twenty eight male beagle dogs with no evidence of neurologic disease were experimented. Allogenic embolus was made using a healthy beagle dog. After internal carotid artery (ICA) was exposure, 16G catheter was introduced through the ICA. The dog was administered 0.3 ml blood clot for 15 seconds followed by 3 ml of saline for 15 seconds. MRI scans were performed with 1.5T to evaluate ischemic lesion at 7 days after middle cerebral artery occlusion procedure. Evaluation parameters of MRI include location, distribution, infarction type, margin, shape, mass effect and intensity of T1-weighted imaging (T1WI), T2-weighted imaging (T2WI), fluid attenuated inversion recovery (FLAIR) sequence, diffusion weighted imaging (DWI) and apparent diffusion coefficient (ADC). On MRI, all dogs (28/28) showed focal or multifocal lesion including telencephalon and thalamus lesions, especially caudate nucleus (24/28). These lesions had well-defined margin from adjacent brain parenchyma, none or mild mass effect and various shape. Most of dogs appeared hyperintensity on T1WI, T2WI, FLAIR, and DWI/ADC, corresponding to chronic infarction. These lesions were histopathologically confirmed atrophic changes and unstained lesion. In conclusion, MRI is the useful method to provide information about ischemic infarction in dogs and the best reproducible ischemic infarction model was developed by using allogenic blood clot.

• Journal of Chest Surgery
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• v.20 no.2
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• pp.342-347
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• 1987

Complete occlusion of the main LCA is associated with a poor prognosis if the RCA becomes severely occluded. The functional role of collateral circulation is critical in this situation. This study lends support to the hypothesis that coronary collateral circulation can provide critically needed myocardial blood flow via right to left collaterals. Not surprisingly, left ventricular function was maintained in 4 of the 5 patients studied who had main LCA occlusion and well-developed collateral circulation.

• Honam Mathematical Journal
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• v.30 no.1
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• pp.75-89
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• 2008

Interrupted blood flow diminishes the concentration of oxygen in tissues. Hypoxia first appears in the region distal to the capillaries and grows throughout the entire t issue. However, the time-wise evolution of hypoxic area is diverse when some of capillaries are blocked in a multi-capillary domain with different oxygen squirt. The process of the development of hypoxia through time course is analyzed mathematically in the domain. Each source in steady state is controlled by a time sensitive function to simulate the occlusion.

• Current Optics and Photonics
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• v.1 no.5
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• pp.433-439
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• 2017

The rodent model has been used frequently to understand stroke pathophysiology, due to its low cost and the large spectrum of genetic strains available. Here, we present a diffuse speckle contrast analysis system (DSCA) with a $1{\times}2$ optical switch that was used to non-invasively assess cerebral blood flow (CBF) changes in the rat during intraluminal suturing for middle cerebral artery occlusion (MCAO) surgery. The blood flow index (BFI) in the left hemisphere was lower than that in the right hemisphere because the left middle cerebral artery was occluded. Furthermore, the performance of the DSCA system was compared with that of commercial laser Doppler flowmetry. The changes in the BFI measured by the two systems were correlated strongly. The DSCA system was less sensitive to motion artifacts and able to measure relatively deep tissue flow in the rat's brain. In conclusion, the DSCA system secured CBF monitoring during surgery in a rodent model without craniotomy.