• Title/Summary/Keyword: blood vessel pressure

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Effect of Non-perceptual Sensory Stimulation Intensity Using Transcutaneous Electrical Nerve Stimulation on Cerebral Blood Flow (경피신경전기자극기를 이용한 비지각적 감각자극 강도가 뇌혈류에 미치는 영향)

  • Ju-Yeon Jung;Chang-Ki Kang
    • Science of Emotion and Sensibility
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    • v.27 no.2
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    • pp.81-90
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    • 2024
  • In this study, we aimed to determine the effect on cerebral blood vessels of various stimulus intensities using transcutaneous electrical nerve stimulation (TENS). In particular, we wanted to monitor changes in blood flow and structural changes in the blood vessels in the common carotid artery (CCA) through low-intensity electrical stimulation that can cause non-perceptual sensory stimulation. Twenty-four healthy adults in their 20s participated in this study. Three stimulus intensities (below the sensory threshold, at the sensory threshold, and above the sensory threshold) were applied in random order. Changes in blood flow velocity according to the intensity of TENS stimulus were measured by placing the Doppler ultrasound transducer 1 cm below the CCA bifurcation, and the vascular structure was measured using B-mode imaging. C-mode Doppler and B-mode images were acquired before, during, and after the intervention for each stimulus, and changes in blood pressure were measured in each session. As a result, it was confirmed that peak systolic velocity (PSV) decreased significantly after the intervention in non-perceived sensory stimulation below the threshold, compared to other thresholds (p = .008). In particular, the PSV decreased by 3.04% on average compared to before stimulation (p = .011). However, there was no significant change in the CCA diameters before and after stimulation at all intensities. It was found that short-term, non-perceptual sensory stimulation was effective in reducing the blood flow rate without causing significant changes in either the blood vessel diameter or blood pressure. This change appears to be caused by a decrease in blood flow due to the effect of subtle vasodilation at non-perceptual sensory stimulation, and at stimulation intensity higher than that, the sympathetic nerves in the blood vessels are stimulated excessively and the blood vessels constrict. Therefore, this study can be rated as an important attempt to control blood flow through stimulation without such a psychological burden and sensory discomfort in the carotid area.

The Effects of Local Anesthetic Agent and Epinephrine on Blood Flow of Femoral Artery in Rabbit (가토에서 국소 마취제와 Epinephrine이 대퇴동맥이 혈류에 미치는 영향)

  • Oh, Soo-Won;Koo, Gil-Hoi;Lee, Choon-Hi
    • The Korean Journal of Pain
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    • v.9 no.1
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    • pp.46-56
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    • 1996
  • Many surgeons and anesthesiologists prefer using vasoconstrictor mixed with local anesthetic agent to reduce the incidence of side effects and prolong the duration of analgesia because most local anesthetic agents, except cocaine, were believed to possess vasodilating effect. However, some investigators recently reported vasoconstricting effect of local anesthetic agents. There is still controversy on the vasoactive effect of local anesthetic agents. So this study is aimed to clarify the vasoactive effect of local anesthetics in the animal model resembling clinical settings. Rabbits were anesthesized with ketamine and haloghane, and respirations were controlled with Harvard animal ventilator. Lidocaine (0.5%, 1.0%, 1.5%) and bupivacaine (0.125%, 0.25% and 0.5%) with or without 1:100,000 epinephrine were subdermaly injected on the femoral bupivacaine of the femoral artery were measured with Doppler flow meter in vivo. The mean arterial pressure, pulse rate, arterial blood gases, pH and level of serum electrolytes were measured at every 2 minute interval for 30 minutes. Results were as follows: 1) There was no significant vasoconstriction with 0.5% lidocaine and 0.125% bupivacaine. 2) Statistically significant (p<0.05) vasodilations were observed with lidocaine (1.0~2.0%) and bupivacaine (0.25~0.5%). 3) There were no changes on the duration of vasodilation induced by local anesthetic agents of various concentrations. 4) Onset of vasodilation induced by local anesthetic agents of high concentration were faster than that of lower concentrations. 5) In the mixed injection group of epinephrine and local anesthetic agent, the vasoconstriction induced by epinephrine was completely reversed by local anesthetics, approximately 5 minutes later. In conclusion, local anesthetic agents at dose exceeding 1.0% lidocaine and 0.25% bupivacaine increase local blood flow significantly in animal study in vivo which is applicable in human clinical settings. The increase blood flow may be due to dilatation of blood vessel. Further study on the analysis of association between amount of absorbed local anesthetics in blood vessels and dilatation of blood vessels is needed.

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A Study on Arterial Characterization using Finger-Toe Index (FTI) (지첨-족지 지수에 의한 동맥 혈관 특성화 연구)

  • Byeon, M.K.;Han, S.W.;Huh, W.
    • Journal of Biomedical Engineering Research
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    • v.28 no.6
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    • pp.777-785
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    • 2007
  • In this paper, Finger-Toe Index (FTI) is proposed as an analytic parameter for the characterization of arterial vessel. Different from the currently being employed pulse wave velocity (PWV) information of the volume pulse wave measured from 4 arterial channels, the proposed FTI uses the ratio of the shorter of the two up-stroke time of PPG from fingers ($UT_{finger}$) and that of PPG (Photoplethysmography) from toes ($UT_{toe}$). To verify the usefulness of the proposed method, Finger-Toe Indexes were derived from the volume pulse waves acquired from 50 people under examination aged from 12 to 81 years old, and they were then compared with blood pressure ankle-brachial index (ABI). It was successfully demonstrated that the arterial stiffness can be estimated with respect to age and FTI is more strongly correlated with the pulse transit time than ABI. From the regression analysis, we also found that FTI has significant correlation PWV for a quantitative index of arterial stiffness and provides more accurate information than ABI for the characterization of arterial vessel.

Serum Fatty Acids in Patients with Angiographically-Documented Coronary Artery Disease (관상동맥질환자의 혈청 지방산 조성에 관한 연구)

  • 김수연
    • Journal of Nutrition and Health
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    • v.32 no.2
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    • pp.166-174
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    • 1999
  • To study the relation between serum fatty acids and coronary artery disease(CAD), 194 subjects were randomly selected and divided into three groups(control, single vessel disease group(SVD), muliple vessel disease group(MVD)) according to the angiographic results. Total serum levels of fatty acids and serum phospholipid(PL)-fatty acids(FAs)were analysed using gas chromatography and their associations with CAD were examined. Different patterns of total serum fatty acid levels were found in men and women. Levels of most fatty acids of SVD and MVD were significantly lower in men, while those of MVD were significantly higher in women. In terms of PL-FAs in both men and women, the levels of PL-FAs follow the order of control < SVD < MVD and in women, the difference was significant. Various ratio(including ratios denoting the activites of desaturase and elongase) of total serum-and PL-FAs were similar in the three groups. In the relation of serum fatty acids to serum lipid profiles, PUFA & LDL showed a negative correlation, while, SFA & LDL-cholesterol and PUFA and HDL-cholesterol showed positive correlatons. correlations. Systolic blood pressure and alcohol intake levels negatively affected the levels of serum LA, AA, EPA and DHA in the risk factor analysis. These findings are consistent with other evidence indicating that fatty acid compositions are changed in CAD, especially on the concentration base and the change was related to the severity of the disease. Therefore, for the purpose of disease prevention and therapeutic use, balanced intakes of various fatty acids must be seriously considered.

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Ultrasonic Targeting of NK Cell in Vessel Bifurcation for Immunotherapy: Simulation and Experimental Validation

  • Saqib Sharif;Hyeong-Woo Song;Daewon Jung;Hiep Xuan Cao;Jong-Oh Park;Byungjeon Kang;Eunpyo Choi
    • Journal of Sensor Science and Technology
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    • v.32 no.6
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    • pp.418-424
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    • 2023
  • Natural killer (NK) cells play a crucial role in combating infections and tumors. However, their therapeutic application in solid tumors is hindered by challenges, such as limited lifespan, tumor penetration, and delivery precision. Our research introduces a novel ultrasonic actuation technique to navigate NK cells more effectively in the vascular system, particularly at vessel bifurcations where targeted delivery is most problematic. We use a hemispherical ultrasonic transducer array that generates phase-modulated traveling waves, focusing on an ultrasound beam to steer NK cells using blood-flow dynamics and a focused acoustic field. This method enables the precise obstruction of non-target vessels and efficiently directs NK cells toward the tumor site. The simulation results offer insights into the behavior of NK cells under various conditions of cell size, radiation pressure, and fluid velocity, which inform the optimization of their trajectories and increase targeting efficiency. The experimental results demonstrate the feasibility of this ultrasonic approach for enhancing NK cell targeting, suggesting a potential leap forward in solid tumor immunotherapy. This study represents a significant step in NK cell therapeutic strategies, offering a viable solution to the existing limitations and promising enhancement of the efficacy of cancer treatments.

A Study on Arterial Characterization by using Up-stroke Time of Photoplethysmogram (용적맥파 상승시간에 의한 혈관 특성화 연구)

  • Byeon, M.K.;Han, S.W.;Huh, W.
    • Journal of IKEEE
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    • v.11 no.3
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    • pp.108-116
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    • 2007
  • This paper proposed an analyzable parameter and its analytic method to provide more accurate information than currently employed 4 channels system which uses pulse wave velocity (PWV) information of the volume pulse wave measured from 4 arterial channels for the characterization of arterial vessel. In order to verify the volume pulse waves on 4 sites were simultaneously acquired subjects aged from 12 to 81 years old. and the proposed parameters were extracted from time (UT) was then compared with blood pressure. Then, the regression analyses were done relationships among the proposed parameter and others, such as aging, pulse transit time pressure (BP). The followings are the results of linear regression analysis of the proposed parameter for total 50 normal subjects. We selected any two subjects (58 years and 27 years) and measured PPG (photoplethysmogram) and BP of before and after exercise. The coefficient of correlations between BP and UT observed was -0.928 for 50 years subject, and -0.922 for 20 years subject. For total 50 normal subjects, in case of correlation between the pulse transit time and BP, the result showed -0.170 on left side and -0.233 on right side, and the coefficient value of correlation between the pulse transit time and UT was -0.607 on left side and -0.510 on right side. UI is strongly correlated with the pulse transit time than BP. Hence, we believe that the proposed parameter is related with the index of arterial stiffness.

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Protein Fraction Extracted from the Earthworm Lumbricus rubellus Activates Proteinase Activated Receptor-2 and is Effective on Hemokinesis (적토룡 추출 단백분획의 프로테나제 유도 수용체-2의 활성화 및 형행개선 효과)

  • Lee, Chul-Kyu;Shin, Jang-Sik;Choi, Young-Keun;Lim, Chae-Kon;Cho, Il-Hwan;Kim, Chul
    • YAKHAK HOEJI
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    • v.41 no.2
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    • pp.247-254
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    • 1997
  • The proteinase-activated receptor (PAR-2) belongs to the family of seven transmembrane region receptors, like the thrombin receptor, it is activated by specific proteolytic clea vage of its extracellular amino terminus and a synthetic peptide (SLIGRL). The earthworm protein fraction (EPF) extracted from Lumbricus rubellus elicted dose- and endothelium-dependent relaxations in phenylephrine-contracted rat thoracic aorta, whereas heat inactivated EPF (0.5 ${\mu}g$ /ml) had no effect. In the presence of the nitric oxide synthase inhibitor NG-methyl-L-arginine (1.8 micro M), EPF (0.5 ${\mu}g$ /ml)-induced relaxations were partially inhibited. Furthermore, EPF (0.5 ${\mu}g$ /ml) dramatically caused relaxation of thrombin-desenstized rat thoracic aorta. These results indicate that EPF activates PAR-2 in vascular endothelial cell. Intravenous injection of EPF (20 mg/kg, bolus) into anesthetized rats produced a marked depressor response. EPF (0 ~ 80 ${\mu}g$ /ml, gradient) was very effective on increasing of perfusion volume in rabbit ear vessel preparations. These results imply the usefulness of EPF as a vascular smooth muscle relaxant and indicate that the activation of PAR-2 may be a mechanism of EPF on hemokinetic improvement.

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Effects of LI11 Acupuncture on CO2 reactivity in the anterior and middle cerebral arteries during hyperventilation-induced hypocapnia in normal subjects: A before and after study.

  • Kim, Gyeong-muk;Jung, Woo-Sang;Kwon, Seungwon;Jin, Chul;Cho, Seung-Yeon;Park, Seong-Uk;Moon, Sang-Kwan;Park, Jung-Mi;Ko, Chang-Nam;Cho, Ki-Ho
    • The Journal of Korean Medicine
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    • v.42 no.4
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    • pp.164-175
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    • 2021
  • Objectives: The LI11 (Quchi) acupuncture point has always been included in the Seven acupoints for stroke; however, additional LI11 acupuncture research is needed. In this study, the effect of LI11 acupuncture on cerebral blood flow of the anterior cerebral arteries (ACA) and middle cerebral arteries (MCA) was investigated. Method: This study included 10 healthy young male subjects. Cerebral blood flow velocity and cerebrovascular reactivity were measured using transcranial Doppler sonography. Changes in hyperventilation-induced carbon dioxide (CO2) reactivity and modified ACA and MCA blood flow velocity at 40 mmHg (CV40), blood pressure, and heart rate were observed before and after LI11 acupuncture treatment. Results: A statistically significant increase in contralateral anterior cerebral artery CO2 reactivity (p=0.036) and decrease in contralateral middle cerebral artery CV40 (p=0.047) were observed. No significant difference in mean blood pressure was shown. A statistically significant increase in heart rate occurred after LI11 acupuncture; however, it was not clinically significant as there were negligible changes in the heart rhythm. Conclusions: LI11 acupuncture treatment could improve cerebral blood flow velocity. These results might be explained by regulating endothelium-dependent vessel dilation in the anterior cerebral artery region. Trial registration: This trial has been registered with Clinical Research Information Service, a service of the Korea Centers for Disease Control and Prevention: KCT0004494 (retrospectively registered). https://cris.nih.go.kr/cris/search/search_result_st01.jsp?seq=15359

Analysis of Pulse Wave Parameters According to Aging for Arteriosclerosis Evaluation (동맥경화 평가를 위한 연령별 맥파 주요인자 분석)

  • Lee, Na-Ra;Lee, Seung-Wook;Kim, Soo-Byeong;Lee, Yong-Heum
    • Korean Journal of Acupuncture
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    • v.28 no.4
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    • pp.79-89
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    • 2011
  • Objectives : The aim of this study is to propose the W area of pulse (AW) as a new index which can confirm the arteriosclerosis by analyzing parameters of 5-level pressure pulse waveform measurement system for normotensive group according to aging. Methods : We measured radial pulse waveforms of normotensive group (20 to 60 years old) using 3-dimensional pulse imaging analyser (DMP-3000, DAEYOMEDI Co., Korea). And then we analyzed various parameters for sclerosis of the arteries such as Height (h1, h2, h3, h4, h5), Time (t1, t2, t3, t4, t5), AW, AW rate, Total area of pulse (At) and Augmentation Index (AIx). Results : As a result of analyzing parameters according to the aging, h2, h3, AS (systolic area rate to AT), AIx and AW were increased but t2/t, t3/t, t5/t and AD (diastolic area rate to AT) were decreased. Conclusions : We checked blood vessel conditions for normotensive group according to aging and confirmed various parameters. Also, we found that AW was analogous to AIx which has been used for diagnosing arteriosclerosis. Furthermore, we confirmed the usefulness of AW as a new parameter for checking vessel condition and characteristic compared with the AIx.

Direct Open Venous Drainage: An Alternative Choice for Flap Congestion Salvage

  • Park, Su Han;Choi, Woo Young;Son, Kyung Min;Cheon, Ji Seon;Yang, Jeong Yeol
    • Archives of Craniofacial Surgery
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    • v.16 no.3
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    • pp.143-146
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    • 2015
  • In this report, we present a scalp defect reconstruction with lateral arm free flap. We highlight the difficulty in obtaining a recipient vein and the venous drainage managed through an open end of the donor vein. A 52-year-old woman presented with a pressure sore on the left scalp. A lateral arm free flap was transferred to cover this $8{\times}6cm$ defect. The arterial anastomosis was successful, but no recipient vein could be identified within the wound bed. Instead, we used a donor venous end for the direct open venous drainage. In order to keep this exposed venous end patent, we applied heparin-soaked gauze dressing to the wound. Also, the vein end was mechanically dilated and irrigated with heparin solution at two hour intervals. Along with fluid management and blood transfusion, this management was continued for the five days after the operation. The flap survived well without any complication. Through this case, we were able to demonstrate that venous congestion can be avoided by drainage of the venous blood through an open vessel without the use of leeches.