• Annals of Clinical Neurophysiology
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• 제1권1호
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• pp.64-69
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• 1999

Background : Syncope was defined as transient loss of consciousness and postural tone. The mechanisms of changes in cerebral hemodynamics during syncope have not been fully evaluated. Transcranial Doppler Ultrasonography can continuously monitor the changes in cerebral hemodynamics during head-up tilt (HUT). TCD could reveal the different patterns of changes in cerebral hemodynamics during syncope. Syncope without hypotension or bradycardia could be detected by TCD. We investigated the changes in cerebral blood flow velocity during HUT using TCD in 33 patients with a history of recurrent syncope or presyncope of unknown origin. Methods & Results : The positive responses were defined as presyncope or syncope with hypotension, bradycardia, or both. During HUT without isoproterenol infusion, there were a $86{\pm}23%$ drop in DV and a $41{\pm}34%$ drop in SV in 5 patients with positive reponses, and mean changes in those were less than 10% in patients with negative reponses (p=.00, p=.00). During HUT with isoproterenol infusion, TCD showed a $80{\pm}18%$ drop in diastolic velocity in 14 patients with positive reponses, and a $47{\pm}10%$ drop in that in patients with negative reponses (p=.00), however the change in systolic velocity did not differ. TCD showed three patterns during positive responses; loss of all flow, loss of end diastolic flow, and a decrease in diastolic velocity. Loss of consciousness occurred in the patients with loss of all flow or end-diastolic flow during positive reponses. Conclusions : TCD shows different patterns of changes in cerebral hemodynamics during HUT. TCD can be used to investigate the pathophysiology of neurocardiogenic syncope.

• Journal of Microbiology and Biotechnology
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• 제26권4호
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• pp.659-665
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• 2016

The oligosaccharides in human milk constitute a major innate immunological mechanism by which breastfed infants gain protection against infectious diarrhea. Clostridium difficile is the most important cause of nosocomial diarrhea, and the C-terminus of toxin A with its carbohydrate binding site, TcdA-f2, demonstrates specific abolishment of cytotoxicity and receptor binding activity upon diethylpyrocarbonate modification of the histidine residues in TcdA. TcdA-f2 was cloned and expressed in E. coli BL21 (DE3). A human milk oligosaccharide (HMO) mixture displayed binding with TcdA-f2 at 38.2 respond units (RU) at the concentration of 20 μg/ml, whereas the eight purified HMOs showed binding with the carbohydrate binding site of TcdA-f2 at 3.3 to 14 RU depending on their structures via a surface plasma resonance biosensor. Among them, Lacto-N-fucopentaose V (LNFPV) and Lacto-N-neohexaose (LNnH) demonstrated tight binding to TcdA-f2 with docking energy of −9.48 kcal/mol and −12.81 kcal/mol, respectively. It displayed numerous hydrogen bonding and hydrophobic interactions with amino acid residues of TcdA-f2.

• 한국방사선학회논문지
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• 제15권5호
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• pp.649-656
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• 2021

본 연구는 태아의 자궁 내 성장제한을 평가하는 변수로 소뇌횡직경과 복부둘레비(TCD/AC ratio)의 적절성을 평가하고자 하였다. 2019년 4월부터 2021년 3월까지 부산소재 I 병원에서 정기검진으로 초음파를 실시한 784명의 임산부를 대상으로 진행하였으며 소뇌횡직경과 복부둘레 측정값을 통해 후향적으로 분석하였다. 단순회귀분석에서 임신주수에 소뇌횡직경은 97.2%, 복부둘레는 97.5%의 영향력을 보였으며(p<0.001) 정상태아의 TCD/AC ratio는 임신주수에 상관없이 13.2로 결정되었다. 또한 빈도분석을 통해 임신주수 그룹별 TCD/AC ratio의 백분위수를 산출하였으며 자궁 내 성장제한 예측의 95 백분위수는 14.2로 나타났다. 결과적으로 TCD/AC ratio는 태아의 정상적인 성장을 평가하고 IUGR을 예측하는 유용한 변수로 활용될 수 있을 것으로 사료된다.

• Annals of Clinical Neurophysiology
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• 제1권1호
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• pp.76-79
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• 1999

The most significant factor in pathogenesis of vascular headaches like migraine and cluster headache is dynamic changes of diameters of the cerebral arteries. TCD is a valuable noninvasive tool to assess the cerebral hemodynamic status by measuring the flow velocities of the intracranial cerebral arteries around the circle of Willis. TCD can evaluate flow velocities and vasoreactivity of the patients with a vascular headache during the ictal phase as well as during intericatal phase. Distribution of the changes recorded differ between types of headaches and also between the major ictal symptoms. The changes suggest the presence of prolonged vasospasm interictally and more marked relaxation of the cerebral arteries. TCD can be used to monitor the long-term clinical course of patients with vascular headache by correlation the symptomatic improvement and TCD data before and after long-term pharmacological prophylactic treatments. During the ictal phases large intervention. The results may be used in selecting and evaluating the agents for abortive therapy for acute attacks. In conclusion TCD can quantitatively evaluate vascular headaches when making diagnosis and classification and can provide guidelines to choose more individualized therapeutic options for both acute and long-term treatment.

• 대한중풍순환신경학회지
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• 제6권1호
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• pp.45-53
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• 2005

Objective : This study was performed to examine the relationship between cerebral blood vessel with meridian by using Transcranial Doppler Ultrasonography(TCD) Method : Monitoring of TCD was examined in 10 healthy people in their twenties (mean age was 26.5±1.00). Each examination was performed before & after acupuncture. Three Meridian were tested. Those were Stomach Meridian, Bladder Meridian & Gallbladder Meridian. Maximum velocity and Mean velocity were analyzed from TCD on different vessel. Result : The results showed significant(p<0.05; Wilcoxon signed rank test) change in some cerebral blood flow after acupuncture. Conclusion : There was the relationship between Meridian and cerebral blood vessel.

• Investigative Magnetic Resonance Imaging
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• 제9권2호
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• pp.94-100
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• 2005

목적 : 뇌혈관 평가에 있어서 경두개 도플러 초음파(transcranial doppler; TCD)와 고식적 뇌혈관조영술(CA)과 비교하여 3T 장비를 이용한 Time-of-flight(TOF) 자기공명 뇌혈관 조영술(3T-TOF MRA)의 유용성에 대해 알아보고자 하였다. 대상 및 방법 : 뇌혈관 질환이 의심된 54명의 환자를 대상으로 3T-TOF MRA를 시행하였다. 54명 모두에서 TCD를 시행하였으며, 이중 11명은 CA를 함께 시행하였다. 뇌혈관의 평가를 위해 추골동맥과 기저동맥을 포함하여 I군, 총경동맥의 분지부위 2 cm 전부터 내 외경동맥 분지 부위에서 내경동맥의 무릎(genu)부위 까지를 II군, 내경동맥의 추체부위에서 전 중 대뇌동맥의 1차분지 부위까지를 III군, 그리고 각각 전 중 대뇌동맥 1차분지 그 이하 부위를 IV군으로 임의로 구분하였다. 평가는 2명의 방사선과 의사가 3T-TOF MRA와 TCD, 그리고 CA의 결과를 모르는 상태에서 각 군에서 혈관의 양상이 잘 나타나는 경우를 3점, 양상이 잘 나타나지 않으나 판독이 가능한 경우를 2점, 잡상 등으로 혈관의 평가가 어려운 경우를 1점으로 하였다. 혈관의 협착 정도에 대한 평가는 TCD 및 CA와 각각 비교하여 그 일치 정도를 평가하였다. 결과 : 각 군당 좌우를 합하여 108 혈관분절, 총 432 혈관분절을 평가하였다. 정성평가에서 I, II, III, IV군은 각각 2.98, 2.96, 2.91, 2.88로 혈관의 양상에 대한 파악은 잘 되는 것으로 나타났다. TCD만을 시행한 43명 중 41명에서 3T-TOF MRA와 TCD가 일치하였고, TCD와 CA를 모두 함께 시행한 11명에서는 3T-TOF MRA가 TCD 및 CA와 모두 일치하였다. 결론 : 3T-TOF MRA는 뇌혈관 평가에 있어서 CA 및 TCD와 비교해서 빠르고 비침습적이며 혈관상태를 적절하게 평가할 수 있는 유용한 검사라고 생각한다.

• Annals of Clinical Neurophysiology
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• 제1권1호
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• pp.70-75
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• 1999

Trancranial Doppler(TCD) monitoring is a new application of ultrasonography which allows the nonivasive detection of blood flow velocity in the horizontal (M1) segment of the middle cerebral artery (MCA) and detects microembolic phenomena in the cerebral circulation. Recent studies emphasized the potential of using this technique in vascular surgery (carotid endarterectomy, cardiopulmonary bypass), interventional and intensive care setting. Although the disparity between CBF and blood flow velocity and number of microemboli could be used to prevent cerebral ischemic and embolism based on clinical studies. A reduction of more than 60% of MCA can reflex hemodynamic ischemic state and acoustic feedback of high intensity transient signals(HITS) from the TCD monitoring unit has a direct influence on surgical technique. TCD monitoring can immediately provide information about thromboembolism and hemodynamic changes, which may be a useful tool in the study and prevention of stroke.

• Annals of Clinical Neurophysiology
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• 제1권1호
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• pp.60-63
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• 1999

Transcranial Doppler(TCD) is an important diagnostic tool for evaluating the patients with stroke. It has some advantages and unique role when compared with other neuroimaging modalities. Recent development of transcranial color-coded Doppler(TCD) improves the limitation and pitfalls of TCD. The current indications of TCD are as follows: 1. Screening and evaluation of the intracranial major vessels 2. early detection and follow-up of vasospasm due to SAH 3. emboli detection (high-imtensity transient signals, HITs) 4. dignosis and follow-up of subclavian steal 5. evaluation of intracranial collaterals when the extracranial ICA has severe stenosis or occlusion 6. evaluation of cerebral perfusion pressure (intracranial pressure) 7. evaluation of arteriovenous malformation 8. diagnosis and follow-up of arterial dissenction 9. diagnosis and follow-up of venous sinus thrombosis (experimental).

• 대한물리치료과학회지
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• 제6권4호
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• pp.153-165
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• 1999

The transcranial Doppler(TCD) is a technique for measuring blood flow velocity of intracranial and extarcranial arteries. This examination based on Doppler effect which was first formulated in 1842 by the Austrian physicist Christian Doppler. In 1982, Rune Aaslid first maked 2MHz pulsed probe and recording intracranial vessels with transcranially. There are six criteria utilized in gaining positive identification of the intracranial vessels. The six criteria are as follows l)acoustical windows 2)depth of sample volume 3)direction of flow 4)spatial relationship of ACA and MCA bifurcation 5)mean velocity and 6)response common carotid artery compression and/or oscillation test. The affected factors for TCD examination are angle of insonation, posture of subject, age, gender, hematocrit, metabolic factors, and cardiac output. Clinical application of TCD are detection of stenosis, occlusion, emboli, thrombsis in intracranial and extracranial arteries and evaluation of cerebral arterovenous malformation, collateral capacity in the circle of Willis, ischemia cerebrovascular disease, stroke patient and vertebrobasilar system.

• International Journal of Contents
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• 제16권1호
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• pp.1-9
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• 2020

Recently, the number of traffic accidents on trunk roads tends to decrease due to the performance improvement of passenger vehicles. In the commuter rush hour of morning and evening, vehicles via residential road increases without going along trunk roads. Therefore, there are many traffic accidents of pedestrians (or bicycles) and vehicles on residential roads. In order to safeguard residents against traffic accidents, traffic calming devices (TCD), such as chicane, speed hump, and school zone, etc. have been introduced. Investigating these effects repeatedly is not easy since many times and efforts are required, such as observed at the place actually. In this paper, the effects of TCDs in residential areas, such as noise, speed, and emission of a vehicle, using Simulation of Urban Mobility (SUMO) are examined. As a result, it is found that it is possible to reduce the speed of the vehicle by TCD, and the level of noise at the location behind TCD becomes higher than the level of noise at the location of TCD implemented.