• Title/Summary/Keyword: Dilation flow

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Retrospective Study of Patent Ductus Arteriosus in 37 Dogs: Clinical Presentations and Interventional Therapy (37마리 개의 동맥관 개존증의 임상소견과 비외과적 치료의 회고연구)

  • Park, Jong-In;Choi, Ran;Lee, Seung-Gon;Hyun, Changbaig
    • Journal of Veterinary Clinics
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    • v.30 no.2
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    • pp.87-94
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    • 2013
  • This retrospective study reviewed the clinical and diagnostic features, therapeutic outcome and compilations of interventional ductal occlusion in 37 dogs with patent ductus arteriosus (PDA). Malteses and female dogs were over-presented. Bounding pulse and left basal continuous murmur were most common findings in physical examination, while the differential cyanosis was rarely observed. Left ventricular (LV) enlargement patterns and sinus tachycardia were common in the ECG. Typical radiographic findings included LV elongation and triple bumps indicating left atrial (LA), aortic and pulmonary dilation. Echocardiographic features were typical shunt flow at the ductus arteriosus and marked LV dilation with mild to moderate mitral regurgitation (MR). The 32 of 37 dogs were interventionally treated with either thromboemolic coils (TCE) or Amplatz canine ductal occluder (ACDO). Transient hemoglobinuria caused by incomplete closure was occurred in 2 dogs treated with TCE, although the hemoglobinuria was disappeared within a week of intervention. The dislodgement of occlusion device was occurred in 2 dogs with TCE and 1 dog with ACDO. However there were no significant complications associated with this dislodgement, since those were dislodged at the lower pulmonary vasculature. We also found that no serious complications and no further medical intervention in 29 dogs having long-term follow-ups.

Effects of Uwhangchungsim-won(Niuhuangqingxin-yuan) on Systemic Blood Pressure, Pulse Rate, Cerebral Blood Flow, and Cerebrovascular Reactivity in Humans (우황청심원(牛黃淸心元)이 정상인의 혈압(血壓), 맥박수(脈搏數), 뇌혈류(腦血流) 및 뇌혈관반응도(腦血管反應度)에 미치는 영향(影響))

  • Yun, Sang-Pil;Lee, Sang-Ho;Kim, Eun-Ju;Na, Byong-Jo;Jung, Dong-Won;Shin, Won-Jun;Moon, Sang-Kwan;Bae, Hyung-Sup;Kim, Lee-Dong
    • The Journal of Internal Korean Medicine
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    • v.25 no.3
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    • pp.440-450
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    • 2004
  • Objectives: Uwhangchungsim-won(UC) has been used in the treatment of a wide variety of conditions including stroke, hypertension, arterosclerosis, autonomic imbalance, and mental instability, in Korean traditional hospitals. The aim of this study was to evaluate the effect of DC on cerebral hemodynamics and to determine the appropriate dosage. Methods: We studied changes in hyperventilation-induced cerebrovascular reactivity and mean blood flow velocity of the middle cerebral arteries(MCAs) were studied by means of transcranial Doppler ultrasound. Changes in mean blood pressure, pulse rate and expiratory CO2(PECO2) were observed using Cardiocap TM/5. Six healthy young volunteers who were administrated with full doses of DC for group A, and half doses for group B. Six other healthy subjects comprised the control group. The evaluation was performed during basal condition, and repeated at 20, 40, 60, 120, and 180 minutes after administration. Results: Increases of cerebrovascular reactivity and mean blood flow velocity in the middle cerebral artery in group A were significantly different compared with group B and the control group (p<0.1). Mean blood pressure, pulse rate and expiratory CO2 did not change during the observation and were not different among these three groups. We observed that in cerebrovascular reactivity induced hyperventilation, group A was most effective at 40 minutes after administration, and its effectiveness lasted for 120 minutes. Conclusions: This study provides evidence for UC, in full doses, as an agent for dilation of the cerebral arteriols to increase hyperventilation-induced cerebrovascular reactivity as a consequence of faster recovery of blood flow velocity.

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Effect of Gastrodia Elata BL Water Extract on Human Cerebral Blood Flow using Transcranial Doppler (천마추출물이 정상인의 뇌혈류에 미치는 영향)

  • Moon Sang-Kwan;Kim Young-Suk;Park Seong-Uk;Jung Woo-Sang;Ko Chang-Nam;Cho Ki-Ho;Bae Hyung-Sup
    • The Journal of Korean Medicine
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    • v.26 no.1 s.61
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    • pp.115-122
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    • 2005
  • Background and objective: Gastrodiae Rhizoma (GR), the rhizoma of Gastrodia elata BL., is one of the popular drugs to treat headache, dizziness, blackout, numbness of limbs, hemiplegia, facial paralysis, dysphrasia, and infantile convulsions. It has been reported that it provides an antihypertensive effect and lowers cerebrovascular resistance in animal experiments. However, there has been no data about these effects with human subjects. In this study, the author examined the effect of Gastrodiae water extracts on blood pressure and cerebrovascular reactivity in human subjects. Methods: We selected 16 normal volunteers, who were divided into 2 groups: Gastrodiae extract administration group and placebo (creamy powder) group. Using transcranial Doppler ultrasound, we monitored changes of mean flow velocity and breath-holding induced CO2 reactivity of middle cerebral artery in both groups. Mean blood pressure, heart rate and PETCO2 were measured using Compact Anesthesia Monitor. In both groups, all evaluation was performed during basal condition, and repeated at 30, 60, and 90 min after administration. Results: Gastrodiae extract decreased CO2 reactivity after administration, reaching the lowest level at 90 minutes $(-29.1\%\;vs.\;basal\;level)$, which showed significant difference compared with the placebo group (p = 0.004). In the placebo group, the pulse rates tended to decrease over time (at 90 minute, $-5.2\%$ vs. basal level) while in the Gastrodiae group the values showed nearly no change, which showed significant difference between both groups (p = 0.036). However, the changes of mean blood pressure and mean flow velocity did not show significant difference between both groups. Conclusion : This study demonstrated that Gastrodiae extract significantly decreased breath-holding induced CO2 reactivity. This result suggests that the clinical effect of Gastrodiae extract might be caused by increasing cerebral blood flow via dilation of cerebral resistant vessels instead of antihypertensive effect.

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Numerical modelling of Fault Reactivation Experiment at Mont Terri Underground Research Laboratory in Switzerland: DECOVALEX-2019 TASK B (Step 2) (스위스 Mont Terri 지하연구시설 단층 내 유체 주입시험 모델링: 국제공동연구 DECOVALEX-2019 Task B(Step 2))

  • Park, Jung-Wook;Guglielmi, Yves;Graupner, Bastian;Rutqvist, Jonny;Park, Eui-Seob
    • Tunnel and Underground Space
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    • v.29 no.3
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    • pp.197-213
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    • 2019
  • We simulated the fault reactivation experiment conducted at 'Main Fault' intersecting the low permeability clay formations of Mont Terri Underground Research Laboratory in Switzerland using TOUGH-FLAC simulator. The fluid flow along a fault was modelled with solid elements and governed by Darcy's law with the cubic law in TOUGH2, whereas the mechanical behavior of a single fault was represented by creating interface elements between two separating rock blocks in FLAC3D. We formulate the hydro-mechanical coupling relation of hydraulic aperture to consider the elastic fracture opening and failure-induced dilation for reproducing the abrupt changes in injection flow rate and monitoring pressure at fracture opening pressure. A parametric study was conducted to examine the effects of in-situ stress condition and fault deformation and strength parameters and to find the optimal parameter set to reproduce the field observations. In the best matching simulation, the fracture opening pressure and variations of injection flow rate and monitoring pressure showed good agreement with field experiment results, which suggests the capability of the numerical model to reasonably capture the fracture opening and propagation process. The model overestimated the fault displacement in shear direction and the range of reactivated zone, which was attributed to the progressive shear failures along the fault at high injection pressure. In the field experiment results, however, fracture tensile opening seems the dominant mechanism affecting the hydraulic aperture increase.

Right coronary artery atresia in Marfan's syndrome: A case report (Marfan 증후군에 동반된 우관상동맥 폐쇄증 - 1 례 보고 -)

  • 이재원
    • Journal of Chest Surgery
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    • v.34 no.9
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    • pp.720-723
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    • 2001
  • A case of Marfan’s syndrome with atresia of right coronary artery is reported. A 45-year-old woman, who was diagnosed as Marfan’s syndrome 1 year ago, came to the hospital complaining of acute chest pain. The patient showed arachynodactyly, pectus carinatum, and long and slender extremities. In echocardiography there were severe aortic regurgitation measured grade IV and aortic dilatation of ascending aorta maximally 5.9 cm in diameter. Mitral regurgitation was mild, but there were also moderate left ventricular dilation and moderately decreased ejection fraction of left ventricle. At operation, atresia of right coronary artery was found. We performed Bentall type operation with SJM 27mm valved conduit for left coronary artery, and Piehler’s modification for right coronary artery bypass using 6mm PTFE graft. The atretic portion of right coronary artery from the suspected right coronary ostium to distal coronary flow was about 4 cm in length. The combination of right coronary artery atresia and Marfan’s syndrome is very rare. The author describes the rare case, which is treated with combined technique of Bentall and Piehler modification for reconstruction of coronary circulation.

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Friction behavior of controlled low strength material-soil interface

  • Han, WooJin;Kim, Sang Yeob;Lee, Jong-Sub;Byun, Yong-Hoon
    • Geomechanics and Engineering
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    • v.18 no.4
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    • pp.407-415
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    • 2019
  • A controlled low strength material (CLSM) is a highly flowable cementitious material used for trench backfilling. However, when applying vertical loads to backfilled trenches, shear failure or differential settlement may occur at the interface between the CLSM and natural soil. Hence, this study aims to evaluate the characteristics of the interface friction between the CLSM and soils based on curing time, gradation, and normal stress. The CLSM is composed of fly ash, calcium sulfoaluminate cement, sand, silt, water, and an accelerator. To investigate the engineering properties of the CLSM, flow and unconfined compressive strength tests are carried out. Poorly graded and well-graded sands are selected as the in-situ soil adjacent to the CLSM. The direct shear tests of the CLSM and soils are carried out under three normal stresses for four different curing times. The test results show that the shear strengths obtained within 1 day are higher than those obtained after 1 day. As the curing time increases, the maximum dilation of the poorly graded sand-CLSM specimens under lower normal stresses also generally increases. The maximum contraction increases with increasing normal stress, but it decreases with increasing curing time. The shear strengths of the well-graded sand-CLSM interface are greater than those of the poorly graded sand-CLSM interface. Moreover, the friction angle for the CLSM-soil interface decreases with increasing curing time, and the friction angles of the well-graded sand-CLSM interface are greater than those of the poorly graded sand-CLSM interface. The results suggest that the CLSM may be effectively used for trench backfilling owing to a better understanding of the interface shear strength and behavior between the CLSM and soils.

Seven Days Breaking Up Prolonged Sitting Improves Systemic Endothelial Function in Sedentary Men (일주일간의 간헐적 좌식차단의 혈관기능 개선 효과)

  • Park, Soo Hyun;Yoon, Eun Sun;Jae, Sae Young
    • Exercise Science
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    • v.26 no.1
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    • pp.61-68
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    • 2017
  • PURPOSE: To examine the cumulative (7 days) effect of breaking up prolonged sitting on systemic endothelial function in sedentary men. METHODS: Thirty sedentary men ($33.93{\pm}5.72years$) participated in two randomized 7 days sitting trial (Sit group (control) vs. Breaks group). The protocol of Breaks group is as follows: 4-minute of moderate-intensity marching in place (walking) every 1 hour during business hour (total: 8 breaks/day). Assessment of brachial artery endothelial function using flow-mediated dilation (FMD) and arterial stiffness indices (augmentation index, arterial pressure and pulse wave velocity) were measured before and after 7 days treatment. RESULTS: Brachial artery FMD significantly increased after 7 days breaking up prolonged sitting treatment (Breaks groups, $9.65{\pm}2.61$ to $9.62{\pm}2.6%$) compared with 7 days prolonged sitting (Sit group, $8.37{\pm}3.41$ to $10.11{\pm}3.75%$) (interaction effect, p=.004). Arterial pressure (AP) significantly increased after treatment (Breaks group, $2.75{\pm}2.19$ to $2.38{\pm}1.63mmHg$, p=.002) in Sit group but there was no change (Sit group, $1.00{\pm}3.18$ to $2.50{\pm}9.23mmHg$) in Breaks groups (interaction effect, p=.008). CONCLUSIONS: These finding show that 7 days regular breaking up prolonged sitting improve in FMD, compared with prolonged sitting. Therefore, regular breaking up prolonged sitting may improve systemic endothelial function in sedentary men.

A Two Mobilized-Plane Model for Soil Liquefaction Analysis (액상화해석을 위한 두 개의 활성면을 가진 구성모델)

  • Park, Sung-Sik
    • Journal of the Korean Geotechnical Society
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    • v.22 no.10
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    • pp.173-181
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    • 2006
  • A Two Mobilized-Plane Model is proposed for monotonic and cyclic soil response including liquefaction. This model is based on two mobilized planes: a plane of maximum shear stress, which rotates, and a horizontal plane which is spatially fixed. By controlling two mobilized planes, the model can simulate the principal stress rotation effect associated with simple shear from different $K_0$ states. The proposed model gives a similar skeleton behaviour for soils having the same mean stress, regardless of $K_0$ conditions as observed in laboratory tests. The soil skeleton behaviour observed in cyclic drained simple shear tests, including compaction during unloading and dilation at large strain is captured in the model. Undrained monotonic and cyclic response is predicted by imposing the volumetric constraint of the water on the drained or skeleton behaviour. This constitutive model is incorporated into the dynamic coupled stress-flow finite difference program of FLAC (Fast Lagrangian Analysis of Continua). The model was first calibrated with drained simple shear tests on Fraser River sand, and verified by comparing predicted and measured undrained behaviour of Fraser River sand using the same input parameters.

Evaluation of Circulating Endothelial Progenitor Cells in Abdominal Aortic Aneurysms after Endovascular Aneurysm Repair

  • Weihua Wu;Jinlong Zhang;Lianbo Shao;Haoyue Huang;Qingyou Meng;Zhenya Shen;Xiaomei Teng
    • International Journal of Stem Cells
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    • v.15 no.2
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    • pp.136-143
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    • 2022
  • Background and Objectives: Circulating endothelial progenitor cells (EPCs) participate in vascular repair and predict cardiovascular outcomes. The aim of this study was to investigate the correlation between EPCs and abdominal aortic aneurysms (AAAs). Methods and Results: Patients (age 67±9.41 years) suffering from AAAs (aortic diameters 58.09±11.24 mm) were prospectively enrolled in this study. All patients received endovascular aneurysm repair (EVAR). Blood samples were taken preoperatively and 14 days after surgery from patients with aortic aneurysms. Samples were also obtained from age-matched control subjects. Circulating EPCs were defined as those cells that were double positive for CD34 and CD309. Rat models of AAA formation were generated by the peri-adventitial elastase application of either saline solution (control; n=10), or porcine pancreatic elastase (PPE; n=14). The aortas were analyzed using an ultrasonic video system and immunohistochemistry. The levels of CD34+/CD309+ cells in the peripheral blood mononuclear cell populations were measured by flow cytometry. The baseline numbers of circulating EPCs (CD34+/CD309+) in the peripheral blood were significantly smaller in AAA patients compared with control subjects. The number of EPCs doubled by the 14th day after EVAR. A total of 78.57% of rats in the PPE group (11/14) formed AAAs (dilation ratio >150%). The numbers of EPCs from defined AAA rats were significantly decreased compared with the control group. Conclusions: EPC levels may be useful for monitoring abdominal aorta aneurysms and rise after EVAR in patients with aortic aneurysms, and might contribute to the rapid endothelialization of vessels.

The Effects of Jayun-tang on the Changes of Cerebral Flow (자윤탕이 뇌혈류 변화에 미치는 영향)

  • Kim Yong-Jin;Jeon Sang-Yoon;Ann Jeong-Jo;Choi Chang-Won;Hong Seok
    • The Journal of Korean Medicine
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    • v.26 no.3 s.63
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    • pp.188-203
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    • 2005
  • Objectives : This study was designed to investigate the effects of Jayun-tang extract (JYT) on the change of cerebral hemodynamics [regional cerebral blood flow (rCBF), pial arterial diameter (PAD) and mean arterial blood pressure (MABP)] in normal and cerebral ischemic rats, na to determine the mechanisms of action of JYT. Methods : We investigated whether JYT inhibits lactate dehydrogenase activity in neuronal cells and cytokines production in serum of cerebral ischemic rats. Results : 1. JYT significantly increased rCBF and PAD in a dose-dependent manner, but MABP was not changed by injecting JYT. These results suggested JYT significantly increased rCBF by dilating PAD. 2. The JYT-induced increase in rCBF was significantly inhibited from pretreatment with indomethacin (1mg/kg, i.p.), an inhibitor of cyclooxygenase and methylene blue $(10{\mu}g/kg, i.p.)$, an inhibitor of guanylate cyclase. 3. The JYT-induced dilation in PAD was significantly inhibited from pretreatment with indomethacin, but was increased by pretreatment with methylene blue. 4 The JYT-induced increase in MABP was reduced by pretreatment with indomethacin and methylene blue. 5. JYT significantly inhibited lactate dehydrogenase activity in neuronal cells. These results suggest that JYT prevented the neuronal death. 6. Both rCBF and PAD were significantly and stably increased by JYT $(10{\mu}g/kg,\;i.p.)$ during the Period or cerebral reperfusion, which contrasted with the findings of rapid and marked increase in the control group. 7. In cytokine production in the serum drawn from femoral artery 1hr after middle cerebral artery occlusion, the sample group showed significantly decreased production of $IL-1\beta$ and $TNF-\alpha$ as well as increased production of IL-10 and $TGF-\beta$ compared with rho control group. 8. In cytokine production in the serum drawn from femoral artery 1hr after reperfusion, the sample group showed significantly decreased production of $IL-1\beta$ and $TNF-\alpha$ as well as significantly increased production of IL-10 and $TGF-\beta$ compared with the control group. Conclusions : JYT mediated by cyclooxygenase had an inhibitive effect on brain damage by inhibiting lactate dehydrogenase activity, $IL-1\beta$ and $TNF-\alpha$ production, and by accelerating IL-10 and $TGF-\beta$ production. The author feels that JYT had anti-ischemic effects through the improvement of cerebral hemodynamics and inhibitive effects on brain damage.

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