• Journal of Korean Neurosurgical Society
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• v.57 no.2
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• pp.77-81
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• 2015

Objective : The purpose of this study was to investigate changes in the plasma level of vascular endothelial growth factor (VEGF) after Gamma Knife radiosurgery (GKRS) for the treatment of meningioma. Methods : Fourteen patients with meningiomas had peripheral venous blood collected at the time of GKRS and at 1 week, 1 month, 3 month and 6 month visits. Plasma VEGF levels were measured using commercially available enzyme-linked immunosorbent assay. For controls, peripheral blood samples were obtained from 20 healthy volunteers. Results : The mean plasma VEGF level (29.6 pg/mL) in patients with meningiomas before GKRS was significantly lower than that of the control group (62.4 pg/mL, p=0.019). At 1 week after GKRS, the mean plasma VEGF levels decreased to 23.4 pg/mL, and dropped to 13.9 pg/mL at 1 month, 14.8 pg/mL at 3 months, then increased to 27.7 pg/mL at 6 months. Two patients (14.3%) with peritumoral edema (PTE) showed a level of VEGF 6 months after GKRS higher than their preradiosurgical level. There was no significant association found in an analysis of correlation between PTE and tumor size, marginal dose, age, and sex. Conclusion : Our study is first in demonstrating changes of plasma VEGF after stereotactic radiosurgery (SRS) for meningioma. This study may provide a stimulus for more work related to whether measurement of plasma level has a correlation with tumor response after SRS for meningioma.

• Journal of Chest Surgery
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• v.15 no.1
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• pp.61-66
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• 1982

The present study was performed to evaluate hemodynamic effects on the pericardial patch graft for stenosis of right ventricle outflow tract in 19 patients of tetralogy of Fallot. The stenosis of right ventricle outflow tract was associated with or without pulmonary annular nar-rowing, pulmonary valvular stenosis, and hypoplastic narrowing of pulmonary artery. Total correction of tetralogy of Fallot was performed under cardiopulmonary bypass with moderate hypothermia and cardioplegic cardiac arrest. Ventricular septal defects were closed with Teflon patch graft. The chamber pressures in the heart were measured before and after a total correction of tetralogy of Fallot. The data of pressure measurement and the results of postoperative observation of pericardial patch were as followings: 1. Systolic and diastolic pressure of right ventricle was decreased after operation from $96.0{\pm}14.7/10.0{\pm}14.4mmHg$ to $61.0{\pm}13.1/8.0{\pm}9.3mmHg$. 2. Systolic and diastolic pressure of pulmonary artery was increased after operation from $18.0{\pm}5.6/10.0{\pm}5.5mmHg$ to $31.0{\pm}10.7/14.0{\pm}4.9mmHg$. 3. Preoperative pressure gradient between right ventricle and pulmonary artery was decreased immediately after operation from 78.0mmHg to 30.0mmHg. 4. It was observed that excellent widening effects of right ventricle outflow tract was resulted from pericardial patch graft. 5. No postoperative bleeding from pericardial patch graft was observed. 6. Aneurysm formation of pericardial patch was not be observed during 1 to 6 years postoperative periods.

• Molecules and Cells
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• v.23 no.2
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• pp.175-181
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• 2007

The present study was undertaken to determine whether $SM22{\alpha}$ participates in the regulation of vascular smooth muscle contractility using $SM22{\alpha}$ knockout mice and, if so, to investigate the mechanisms involved. Aortic ring preparations were mounted and equilibrated in organ baths for 60 min before observing contractile responses to 50 mM KCl, and then exposed to contractile agents such as phenylephrine and phorbol ester. Measurement of isometric contractions using a computerized data acquisition system was combined with molecular or cellular experiments. Interestingly, the aortas from $SM22{\alpha}$-deficient mice ($SM22^{-/-LacZ}$) displayed an almost three-fold increase in the level of $SM22{\beta}$ protein compared to wild-type mice, but no change in the levels of caldesmon, actin, desmin or calponin. $Ca^{2+}$-independent contraction in response to phenylephrine or phorbol ester was significantly decreased in the $SM22{\alpha}$-deficient mice, whereas in the presence of $Ca^{2+}$ neither contraction nor subcellular translocation of myosin light chain kinase (MLCK) in response to phenylephrine or 50 mM KCl was significantly affected. A decrease in phosphorylation of extracellular signal regulated kinase (ERK) 1/2 was observed in the $SM22{\alpha}$-deficient mice and this may be related to the decreased vascular contractility. Taken together, this study provides evidence for a pivotal role of $SM22{\alpha}$ in the regulation of $Ca^{2+}$-independent vascular contractility.

• The Korean Journal of Physiology and Pharmacology
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• v.14 no.1
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• pp.51-57
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• 2010

It was hypothesized that NaF induces calcium sensitization in $Ca^{2+}$-controlled solution in permeabilized rat mesenteric arteries. Rat mesenteric arteries were permeabilized with $\beta$-escin and subjected to tension measurement. NaF potentiated the concentration-response curves to $Ca^{2+}$ (decreased $EC_{50}$ and increased $E_{max}$). Cumulative addition of NaF (4.0, 8.0 and 16 mM) also increased vascular tension in $Ca^{2+}$-controlled solution at pCa 7.0 or pCa 6.5, but not at pCa 8.0. NaF-induced vasocontraction and $GTP{\gamma}S$-induced vasocontraction were not additive. NaF-induced vasocontraction at pCa 7.0 was inhibited by pretreatment with Rho kinase inhibitors H1152 or Y27632 but not with a MLCK inhibitor ML-7 or a PKC inhibitor Ro31-8220. NaF induces calcium sensitization in a $Ca^{2+}$ dependent manner in $\beta$-escin-permeabilized rat mesenteric arteries. These results suggest that NaF is an activator of the Rho kinase signaling pathway during vascular contraction.

• Journal of Ginseng Research
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• v.16 no.3
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• pp.175-182
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• 1992

Intravenous administration of saponin from the root of Panax ginseng (red ginseng) lowered the blood pressure in a dose-dependent manner (10~100 mg/kg B.W) in anesthetized rats. Therefore, experiments were designed to study whether this lowering of blood pressure is associated with the release of endothelium-derived relaxing factor. Rings of thoracic aorta with and without endothelium were suspended for the measurement of isometric tension in organ chamber. All experiments were performed in the presence of indomethacin (10-5 M). Ginseng saponin (10-5~3$\times$10-4 g/ml) relaxed contractions induced by phenylephrine (10-5 M) in the aorta with endothelium but not in that without endothelium. Treatment of aortic rings with NG_monomethyl-L-arginine (L-NMMA 10-4 M for 30 min), a competive inhibitor of nitric oxide synthase and methylene blue (M.B., 3$\times$10-7 M for 30 min), an inhibitor of soluble guanylate cyclase, diminished the relaxation induced by ginseng saponin. In thoracic aortic rings from rats treated with ginseng saponin for 2 weeks intraperitoneally, the relaxation to acetylcholine was increased compared with non-ginseng treated rings. These data suggest that red ginseng saponin evokes hypotension and that vascular relaxations induced by red ginseng saponin are inediatpd by release of endothelium-derived relaxing factor.

• Korean Journal of Veterinary Research
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• v.45 no.3
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• pp.423-427
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• 2005

Color Doppler imaging (CDI) was carried out to evaluate the anesthetics effect on ophthalmic circulation using CDI-derived resistive index (RI) values. CDI was preformed on 24 dogs, and RI values were calculated for the medial long posterior ciliary artery (mLPCA) and ophthalmic artery (OA) before and after administration of anesthetics. After administration of benoxinate or acepromazine, a significant change of the mLPCA RI was not found. But, a significant decrease of the RI following ketamine (p < 0.001) or xylazine (p < 0.01) administration could be observed as compared with the self-control. Mean RI value of OA also showed this same trend. Intraocular pressure was significantly decrease following benoxinate (p < 0.01), acepromazine (p < 0.01), and xylazine (p < 0.001) administration within normal range. The results suggest that some anesthetics influence on ophthalmic vascular resistance. Therefore, chemical restraint was carefully used in clinical application of CDI-derived RI measurement. Particularly, benoxinate and acepromazine is useful chemical restraint without a change of the ophthalmic vascular resistance.

• Molecules and Cells
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• v.27 no.2
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• pp.191-198
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• 2009

The present study was undertaken to determine whether treatment with genistein, the plant-derived estrogen-like compound influences agonist-induced vascular smooth muscle contraction and, if so, to investigate related mechanisms. The measurement of isometric contractions using a computerized data acquisition system was combined with molecular experiments. Genistein completely inhibited KCl-, phorbol ester-, phenylephrine-, fluoride- and thromboxane $A_2$-induced contractions. An inactive analogue, daidzein, completely inhibited only fluoride-induced contraction regardless of endothelial function, suggesting some difference between the mechanisms of RhoA/Rho-kinase activators such as fluoride and thromboxane $A_2$. Furthermore, genistein and daidzein each significantly decreased phosphorylation of MYPT1 at Thr855 had been induced by a thromboxane $A_2$ mimetic. Interestingly, iberiotoxin, a blocker of large-conductance calcium-activated potassium channels, did not inhibit the relaxation response to genistein or daidzein in denuded aortic rings precontracted with fluoride. In conclusion, genistein or daidzein elicit similar relaxing responses in fluoride-induced contractions, regardless of tyrosine kinase inhibition or endothelial function, and the relaxation caused by genistein or daidzein was not antagonized by large conductance $K_{Ca}$-channel inhibitors in the denuded muscle. This suggests that the RhoA/Rho-kinase pathway rather than $K^+$- channels are involved in the genistein-induced vasodilation. In addition, based on molecular and physiological results, only one vasoconstrictor fluoride seems to be a full RhoA/Rho-kinase activator; the others are partial activators.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.834-837
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• 2005

In this paper, we describe the method of non-invasive blood pressure measurement using pulse wave transit time(PWTT). PWTT is a new parameter involved with a vascular that can indicate the change of BP. PWTT is measured by continuous monitoring of ECG and pulse wave. No additional sensors or modules are required. In many cases, the change of PWTT correlates with the change of BP. We measure pulse wave using the photo plethysmograph(PPG) sensor in an earlobe and we measure ECG using the ECG monitoring device our made in the chest. The measurement device for detecting pulse wave consists of infrared LED for transmitted light illumination, pin photodiode as light detector, amplifier and filter. We composed 0.5Hz high pass, 60Hz notch and 10Hz low pass filter. ECG measurement device consists of multiplexer, amplifier, filter, micro-controller and RF module. After amplification and filtering, ECG signal and pulse wave is fed through micro-controller. We performed the initial work towards the development of ambulatory BP monitoring system using PWTT. An earlobe is suitable place to measure PPG signal without the restraint in daily work. From the results, we can know that the dependence of PWTT on BP is almost linear and it is possible to monitoring an individual BP continuously after the individual calibration.

• Journal of Sensor Science and Technology
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• v.27 no.4
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• pp.259-263
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• 2018

A radial artery pulse wave is measured while pressing an artery with constant force. However, pulse waveform measurements vary depending on pressing force and direction. Accurate pulse waveform measurements are important for analysis. Thus, it is necessary to define the measurement range of the permissible force and direction from which a correct pulse waveform is derived. In this study, pulse waves were generated by a pulse wave generator for accurate control. The pulse waves generated for different angles and pressing forces were analyzed. The augmentation index (AIx), which is the most commonly used index for evaluating vascular stiffness, was analyzed. The AIx was measured within ${\pm}6^{\circ}$ of the vessel direction and within ${\pm}8^{\circ}$ perpendicular to the vessel direction with a force that was 25% or more of the pressing force at which the maximum pressure wave was generated. We identified the applicable pressing force and angle range by analyzing the effect of pressing angle on the pulse wave. The AIx analysis performed using the pulse wave measurement device is reliable and reproducible.

• Journal of the Optical Society of Korea
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• v.19 no.2
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• pp.169-174
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• 2015

Muscle vibration measurement has long been an unique scientific study, in general, and the direct reaction of animals to feel pain (algesia), either from vascular or muscle contraction, is a complex perceptual experience. Thus this paper proposes a way to measure animal algesia quantitatively, by measuring the changes in muscle vibration due to a pinprick on the surface of the skin of a Spodoptera litura larva. Using the laser optical triangulation measurement principle, along with a CMOS image sensor, linear laser, software analysis, and other tools, we quantify the subtle object point displacement, with a precision of up to $10{\mu}m$, for our chosen Spodoptera litura larva animal model, in which it is not easy to identify the tiny changes in muscle contraction dynamics with the naked eye. We inject different concentrations of formalin reagent (empty needle, 12% formalin, and 37% formalin) to obtain a variety of different muscle vibration frequencies as the experimental results. Because of the high concentrations of reagent applied, we see a high frequency shift of muscle vibration, which can be presented as pain indices, so that the algesia can be quantified.