• Journal of Biomedical Engineering Research
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• v.23 no.6
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• pp.437-449
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• 2002

Coronary arteries are subjected to very different flow conditions compared to other arteries in systemic blood circulation. We Performed a computational fluid dynamic research to investigate influence of such flow conditions in coronary arteries on development and progress of atherosclerosis in the same. The results showed big differences in the flow field of the coronary artery compared to the abdominal and femoral arteries. The coronary artery showed higher wall shear stresses due to the small vessel diameter. On the other hand, it showed only one vortex distal to the stenosis throat during a whole pulse cycle. However. several vortices were observed in the abdominal and femoral arteries in both proximal and distal sides of the stenosis throat The wall shear stresses and extent of recirculation area were increased with impedance phase angle increasing toward more negative values. Therefore, cardiac contraction and the negative impedance phase angle as large as -110。 may induce a flow field that accelerates atherosclerosis.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.1
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• pp.69-74
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• 2004

We have examined the relaxative response to the water extract of Rheum undulatum L. (ERU) and water extract of alcohol steamed Rheum undulatum L. (SRU) with isolated thoracic aorta from sprague dawley (SD) rat. Rat thoracic aorta was investigated in vessel segments suspended for isometric tension recording by polygraph. Responses to ERU and SRU were investigated in vessels precontracted with 5-hydroxytryptamine(5-HT). We found that the thoracic aorta segments responded to ERU and SRU with a dose-dependent vasorelaxation : The thoracic aorta segments responded to ERU and SRU with a dose-dependent vasodilation. The amounts of emodin were 0.063%, 0.076% and 0.145% in ERU and SRU, respectable. The 5-HT induced contraction at 10-4M were inhibited by 85.2±4.76% and 84.0±2.91% after addition of the 0.1mg/mL water extract of ERU and SRU. The 5-HT induced contraction at 10/sup -3/M were inhibited by 100% after 10/sup -3/M emodin. In conclusion, vasodilation effect of the water extract of Rheum undulatum L. in rat thoracic aorta was not decreased according to the processing of alcohol steamed Rheum undulatum L.

• Journal of Physiology & Pathology in Korean Medicine
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• v.27 no.1
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• pp.34-42
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• 2013

Our study is to review Chinese traditional medicine's journals about the diagnosis and treatment of spasmodic torticollis such as category, syndrome differentiation, acupoints of treatment, and herbal medicine. The journal search was performed using the search engine of China Academic Journal (CAJ) and China Doctor/Master's Dissertation (CDMD) in China National Knowledge Infrastructure (CNKI) from January 1982 to October 2012. Searching key words were the diverse combination of "spasmodic torticollis", "cervical dystonia", "Chinese traditonal medicine", "herbal medicine", "acupuncture", and "syndrome differentiation". The inclusion criteria was all kinds of journals including Chinese traditional medicine approach except for experiment study. The category, syndrome differentiation, acupoints of treatment, and herbal medicine from finally selected journals were extracted and summarized. The fourty-seven Chinese journals were selected finally. The category was divided into wind syndrome, trembling syndrome, convulsive syndrome, and convulsions. The syndrome differentiation was classified as internal stirring of liver wind, yin-blood depletion, invasion of external contraction, uncontrol of governor vessel, internal obstruction of phlegm turbidity, dual deficiency of qi and blood, and blood stasis due to qi stagnation. The combination of acupoints to unblock the meridian and dissipate binds and to tonify governor vessel and repel tremor was mainly used in acupuncture treatment. Galgun-tang or galgun-tanggami was primarily used and the others were the prescriptions to tonify liver and kidney, to calm convulsion, and to dispeling wind-phlegm. We suggests that spasmodic torticollis could be treated using Korean medicine's approach in Korea.

• The Korean Journal of Physiology
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• v.17 no.1
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• pp.45-54
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• 1983

Contractile responses of myocardium and vascular smooth muscle to angiotensin II were studied in isolated rabbit papillary muscles and aortic helical strips, with respect to the sensitivity and the mechanism of action. All experiments were performed in $HCO-_3\;-buffered Tyrode solution which was aerated with $3%\;CO_2-97%\;O_2$ and kept pH 7.35 at $35^{\circ}C$. Action potentials were measured by conventional microelectrode technique in the papillary muscles. Helical strips of vascular smooth muscle were prepared from the descending thoracic aorta of the rabbit. Angiotensin II elicited a positive inotropic effect in doses from $10^{-8}$ to $10^{-6}\;M$, and this effect was dose-dependent and characterized by a symmetrical increase of maximum dP/dt during contraction and relaxation phase. Slow responses (or slow action potentials) were induced by A. II $(10^{-6}\;M)$ in the papillary muscle hypopolarized by 27 mM $K^+$. These A. II-induced slow action potentials were eliminated by verapamil (2 mg/l), but not affected by propranolol $(10^{-5}\;M)$. In aortic helical strips, contractile force was increased dose-dependently in the range of $10^{-10}{\sim}10^{-7}\;M$ A. II. $ED_{50}$ in aorta was $3{\times}10^{-9}\;M$ A. II, whereas that in paillary muscle was $2.5{\times}10^{-7}\;M$ A. II. A. II contracted vascular smooth muscle in depolarizing concentration of $K^+$ (100 mM $K^+$), and also produced a sustained contraction even in the presence of verapamil and regitine. The results of this experiment suggest that the primarily important physiological role of A. II is the action on the blood vessel, and the positive inotropic effect of A. II in papillary muscle results from the increase of slow inward $Ca^{++}$ current, and that A. II-induced contraction of aorta is independent of transmembrane potential and associated with promoting bet transmembrane $Ca^{++}\;-influx$ and the mobilization of cellular $Ca^{++}$.

• The Journal of Internal Korean Medicine
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• v.24 no.2
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• pp.220-232
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• 2003

Objective : The purpose of this study was to analyze the effects of HwangRyunHaeDok-Tang and combinations of constituent herbs on the arterial contraction. Methods : In order to investigate the effects Scutellariae Radix. Coptidis Rhizoma, Phellodendri Cortex and Gardeniae Fructus, in which one of them, two of them, and all of them, were used to exam. Results : The results were summarized as follows; 1. HwangRyunHaeDok-Tang significantly inhibited the contraction of artery induced by Norepinephrine(NE). However the atonic effect was slightly blunted when the vascular endothelial cell was removed. No significant change in the atonic effect of HwangRyunHaeDok-Tang was found when $_L-NNA$ was used as a preliminary treatment. These results indicate that the vascular atonic effect by HwangRyunHaeDok-Tang is slightly dependent on the endothelial cell, and that the HwangRyunHaeDok-Tang works directly to the vascular smooth muscle in creating the vascular atonic effect. 2. The pretreatment of HwangRyunHaeDok-Tang extract significantly inhibited the contractile response to additive application of $Ca^{2+}$ in the strips which were contracted by NE in $Ca^{2+}$-free solution. 3. HwangRyunHaeDok-Tang extract increased the contraction of arterial smooth muscle induced by KCl. Therefore, it can be concluded that HwangRyunHaeDok-Tang may block the NE-receptor or receptor-operated $Ca^{2+}$ channel. 4. It was determined that Scutellariae Radix, Coptidis Rhizoma and Phellodendri Cortex among the ingredients of HwangRyunHaeDok-Tang have a vascular atonic effect. In addition, those ingredients plays a role in strengthening the atonic effect by working with other herbal medicines. Gardeniae Fructus causes the blood vessel to contract. but it does not influence the atonic effects of other herbal medicines. However Gardeniae Fructus tends to inhibit the vascular atonic effect of Phellodendri Cortex. Conclusion : Based on the above results, it can be said that HwangRyunHaeDok-Tang can be applied to cure hypertension considering those three herbs have significant effects of relaxation.

• The Journal of Korean Medicine
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• v.23 no.3
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• pp.63-73
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• 2002

Objective : This study aimed to investigate the effects Samyoo-tang Extract (SE) on the vascular systems, including changes in blood pressure and regional cerebral blood flow (rCBF), of male Sprague-Dawley rats. Methods : The changes in rCBF were determined by Laser-Doppler flowmetry through the opened cranial method and norepinephrine (NE)-induced blood vessel contractions were determined by physiograph in the pulmonary artery of isolated rabbits. Results and Conclusion : 1. Contractions evoked by NE ($ED_{50}$) were inhibited significantly by SE in the pulmonary artery. 2. SE inhibited the relaxation of NE induced contractions pretreated with propranolol. 3. SE did not inhibit the relaxation of NE induced contractions pretreated with ODQ and L-NNA. 4. Blood pressure was not affected by SE in rats. 5. rCBF was increased by SE in a dose-dependent manner. 6. Pretreatment with propranolol was increased by SE in a dose-dependent manner in blond pressure. 7. Pretreatment with methylene blue, ODQ and L-NNA did not inhibit SE induced increased in rCBF. These results indicate that SE can relax NE-induced contraction of rabbit blood vessels and increased the changes of rCBF in rats, that relate to the sympathetic nerve system.

• Journal of Ocean Engineering and Technology
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• v.17 no.4
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• pp.31-36
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• 2003

In case of this thick rolling-steel for a multistory building, a large oil-drilling structure, a large vessel, a bridge and so on, Lamella Tearing around the welded joint zone is the most serious problems. In order to prevent Lamella Tearing, not only is choice of material important, but also the comprehensive investigation for the structural design and the construction. The Lamella Tearing that is a staircase-shape occurs due to the contraction stress to the thickness direction of the plate and has the character that the cracks progress along the elongated inclusion by rolling. In general, because cracks occur at the heat affected zone and around HAZ, it is necessary to establish the safety and the confidence of the welded structure to restrain the welding defect such as Lamella Tearing. The mechanical approaches are the easier and more economical than the approaches of the material and the construction method. In addition, the appropriate welding profile and the optimum welding condition contribute toward the improvement of the productivity and influence on the standardization of the manufacturing technology.

• Biomolecules & Therapeutics
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• v.16 no.4
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• pp.299-305
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• 2008

Active cardiovascular anaphylactic response was induced in ovalbumin-sensitized, pithed Sprague-Dawley and Wistar rats. On intravenous administration of the antigen, ovalbumin, marked tachycardia and pressor responses were immediately elicited. Thereafter, a delayed long-lasting severe hypotensive response was observed. These anaphylactic cardiovascular responses were maximal 2-3 weeks after the sensitization, and the response was slightly diminished 6 weeks after sensitization. The immediate pressor response was blocked by a non-selective serotonin antagonist methysergide at a dose-dependent manner, but not by histamine receptor antagonists mepyramine (pyrilamine) or cimetidine. The delayed hypotension was reduced either by histamine $H_1$ receptor antagonist mepyramine or $H_2$ receptor antagonist cimetidine, both in a dose-dependent manner. The tachycardic response was not influenced by serotonin or histamine receptor antagonists examined in this study. Differently from the cardiovascular responses, there was no observable bronchial contraction in Sprague-Dawley rat trachea in contrast to Wistar rat where the trachea contracted to in vitro antigen challenge. The cardiovascular anaphylactic model seems to be useful for studying cardiovascular events that occur exclusively in peripheral heart-blood vessel systems. The involvement of two major anaphylactic mediators, serotonin and histamine, is partially demonstrated.

• Journal of Navigation and Port Research
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• v.32 no.2
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• pp.121-126
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• 2008

This paper presents hull stress monitoring system installed in LNGC damaged by a Typhoon Elongation/contraction of removed areas has been assessed in terms of possible residual stress that will take place in replaced blocks when the applied load is removed. The bending moment of a vessel changes actually in terms of loss of longitudinal members and the change of weight distribution in repair procedure. The change of bending moment affects mainly in hull stress of longitudinal members. Hull stress monitoring system was installed on upper deck to prove LNGC stable in the criteria to be less than 40MPa during the period of repair procedure. A temperature measuring system was also installed to exclude the additional stress due to thermal effect from the measured hull stress. As a result, the hull stress was modified with the data measured by the temperature measuring system. This hull stress considering thermal effect was used as a guide stress to check the safety of LNGC during the period of repair procedure.

• Journal of Biomedical Engineering Research
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• v.25 no.6
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• pp.599-604
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• 2004

Implantable flexible sensor using polymer/metal multilayer processing technique for telemetrical real-time blood pressure monitoring is presented. The realized sensor is mechanically flexible, which can be less invasively implanted and attached on the outside of blood vessel to monitor the variation of blood pressure. Therefore, unlike conventional detecting methods which install sensor on the inside of vessel, the suggested monitoring method can monitor the relative blood pressure without injuring blood vessel. The major factor of sudden death of adults is a disease of artery like angina pectoris and myocardial infarction. A disease of circulatory system resulted from vessel occlusion by plaque can be preventable and treatable early through continuous blood pressure monitoring. The procedure of suggested new method for monitoring variation of blood pressure is as follows. First, integrated sensor is attached to the outer wall of blood vessel. Second, it detects mechanical contraction and expansion of blood vessel. And then, reader antenna recognizes it using telemetrical method as the relative variation of blood pressure. There are not any active devices in the sensor system; therefore, the transmission of energy and signal depends on the principle of mutual inductance between internal antenna of LC resonator and external antenna of reader. To confirm the feasibility of the sensing mechanism, in vitro experiment using silicone rubber tubing and blood is practiced. First of all, pressure is applied to the silicone tubing which is filled by blood. Then the shift of resonant frequency with the change of applied pressure is measured. The frequency of 2.4 MHz is varied while the applied pressure is changed from 0 to 213.3 kPa. Therefore, the sensitivity of implantable blood pressure is 11.25 kHz/kPa.