Accuracy of cardiac output measurements during off-pump coronary artery bypass grafting: according to the vessel anastomosis sites

Sung Yong Park,Dae Hee Kim,Han Bum Joe,Ji Young Yoo,Jin Soo Kim,Min Kang,Yong Woo Hong 대한마취통증의학회 2012 Korean Journal of Anesthesiology Vol.62 No.5

Background: During beating heart surgery, the accuracy of cardiac output (CO) measurement techniques may be influenced by several factors. This study was conducted to analyze the clinical agreement among stat CO mode (SCO), continuous CO mode (CCO), arterial pressure waveform-based CO estimation (APCO), and transesophageal Doppler ultrasound technique (UCCO) according to the vessel anastomosis sites. Methods: This study was prospectively performed in 25 patients who would be undergoing elective OPCAB. Hemodynamic variables were recorded at the following time points: during left anterior descending (LAD) anastomosis at 1 min and 5 min; during obtuse marginal (OM) anastomosis at 1 min and 5 min: and during right coronary artery (RCA) anastomosis at 1 min and 5 min. The variables measured including the SCO, CCO, APCO, and UCCO. Results: CO measurement techniques showed different correlations according to vessel anastomosis site. However, the percent error observed was higher than the value of 30% postulated by the criteria of Critchley and Critchley during all study periods for all CO measurement techniques. Conclusions: In the beating heart procedure, SCO, CCO and APCO showed different correlations according to the vessel anastomosis sites and did not agree with UCCO. CO values from the various measurement techniques should be interpreted with caution during OPCAB. Background: During beating heart surgery, the accuracy of cardiac output (CO) measurement techniques may be influenced by several factors. This study was conducted to analyze the clinical agreement among stat CO mode (SCO), continuous CO mode (CCO), arterial pressure waveform-based CO estimation (APCO), and transesophageal Doppler ultrasound technique (UCCO) according to the vessel anastomosis sites. Methods: This study was prospectively performed in 25 patients who would be undergoing elective OPCAB. Hemodynamic variables were recorded at the following time points: during left anterior descending (LAD) anastomosis at 1 min and 5 min; during obtuse marginal (OM) anastomosis at 1 min and 5 min: and during right coronary artery (RCA) anastomosis at 1 min and 5 min. The variables measured including the SCO, CCO, APCO, and UCCO. Results: CO measurement techniques showed different correlations according to vessel anastomosis site. However, the percent error observed was higher than the value of 30% postulated by the criteria of Critchley and Critchley during all study periods for all CO measurement techniques. Conclusions: In the beating heart procedure, SCO, CCO and APCO showed different correlations according to the vessel anastomosis sites and did not agree with UCCO. CO values from the various measurement techniques should be interpreted with caution during OPCAB.

동맥혈 채혈후 시간 경과 및 온도 변화가 가스분압 및 PH 에 미치는 영향에 관한 연구

김동수,이승환,김건식,강화자,신광일,여민구 대한마취과학회 1989 Korean Journal of Anesthesiology Vol.22 No.6

Blood gas samples are highly susceptible to preanalytic error due to improper methods of obtaining or handling the sample prior to delivery to the laboratory. The errors in the measurement of blood gas analysis are currently derived from the exposure of sample to atmosphere, effects of anticoagulant itself, temperature difference between the measuring electrode and drawn blood and the delay in running the sample. To study the effects of the delay in measuring the sample and the temperature difference between the measuring electrode and drawn blood on values of blood gases and pH, we analyzed the arterial sampling from the 24 patients who were taking elective surgery or on his/her recovery period with indwelling arterial catheter. The plastic sampling syringes were kept at 4。C (refrigerator) or 22。-24。C (room temperature) and analyzed at regular intervals (1, 10, 30, 60,120 min) for 120 minutes. The following results were obtained: 1) When the arterial blood drawn from the anesthetized patients were stored 4。C, partial pressure of oxygen (PaO₂) decreased significantly after 20 min, whereas those stored at room temperature decreased significantly after 10 min. 2) When the arterial blood drawn from the recovery patients were stored at 4。C, PaO₂ did not decrease significantly through the experimental period of 120 min. Although those stored at room temperature did not decrease significantly through the period of 120 min. 3) Partial pressure of carbon dioxide in the arterial blood (PaCO₂,) drawn from the anesthetized patients increased significantly by 120 min. at 4。C, whereas those at room temperature increased significantly after 20 min. 4) PaCO₂, of the recovery patients increased signigicantly by 120 min. at 4。C, whereas those at room temperature increased significantly after 30 min. 5) pH of the arterial blood drawn from either anesthetized or recovery patients decreased significantly by 120 min. at 4。C, whereas those at room temperature decreased significantly after 60 min. 6) No significant changes al oxygen saturation (SaO₂) and content (CaO₂) were noted in either anesthetized or recovery. patients in accordance with time elapsed at 4。C or room temperature. In summary, as the changes of PO₂ in particular higher than physiologic PO₂ and PCO₂ in the arterial blood stored at room temperature are significant in accordance with the delay in measuring, it would be advisable to analyze the sample in a short period of time or to store it in a cool place when the measuring will be delayed.

총경동맥 폐쇄시간에 따르는 국소 뇌혈류 변화 : 실험적 연구 An Experimental Cat Model

강준기,성태경,조병일,백민우,김문찬,허춘웅,하영수,송진언 대한신경외과학회 1983 Journal of Korean neurosurgical society Vol.12 No.3

The microvasculature of the brain is also quite susceptible to ischemic insult, and substantial portions of the brain are not reperfused after restoration of the blood supply following overtime of critical ischemic periods. The purpose of this series of experiments was to determine the effects of ischemia on subsequential regional cerebral blood flow measurements and cortical electric activities following reperfusion after ischemia and also to define the proper time of vascular occlusion without irreversible neural damage. Cerebral ischemia was induced in cat by bilateral common carotid occlusions for periods of 10, 30, to 60 minutes, and the blood supply was reperfused for 3 hours after clamp-off. Regional cerebral blood flow(rCBF) was measured by hydrogen clearance technique following ischemia, restoration of blood supply and electroencephalogram recovery could be predicted according to the rCBF. Forty adult cats weighing 2.7 to 4.0㎏ were used in this study. The animals were divided into 4 groups of 10 cats each : normal control, 10 min-clamped, 30 min-clamped, and 60 min-clamped groups. The results obtained were as follows : 1) The mean rCBF was 24.6±7.0㎖/100g/min in control group. 2) Bilateral carotid occlusions resulted in a reduction of the rCBF(12.4±4.1㎖/100g/min) to 50% of control flow on both hemispheres. 3) Sequential changes of the rCBF after reperfusion : (1) There was restored the rCBF(21.3±5.1㎖/100g/min) to control flow in the 10 minutes-clamped group. (2) There was a 85% recovery of control flow in the 30 minutes-clamped group. (3) There was a only 25% recovery of control flow in the 60 minutes-clamped group. 4) A close correlation was found between cortical electrical activity and rCBF suggesting a threshold relationship. (1) The changes of cortical electric activity began to notice at rCBF less than 17.4±4.7㎖/100g/min. (2) The recovery of cortical electric activity noted at rCBF more than 10.2±2.3㎖/100g/min. 5) There was no evidence of ischemic involvement at the cortex, white matter and basal ganglia in the 10 minutes clamped group, but demonstrated a dense wedge shaped infarct at the cortex and uncus herniation in the 60 minutes clamped group. The rCBF and cortical electric activity restored to normal values in reperfusion within 10 minutes after occlusion of both common carotid arteries.

Comparative evaluation of the algorithms for parametric mapping of the novel myocardial PET imaging agent ¹⁸ F-FPTP

Kim, Ji Who,Seo, Seongho,Kim, Hyeon Sik,Kim, Dong-Yeon,Lee, Ho-Young,Kang, Keon Wook,Lee, Dong Soo,Bom, Hee-Seung,Min, Jung-Joon,Lee, Jae Sung Springer Japan 2017 Annals of nuclear medicine Vol.31 No.6

<P><B>Objective</B></P><P>(<SUP>18</SUP>F-fluoropentyl)triphenylphosphonium salt (<SUP>18</SUP>F-FPTP) is a new promising myocardial PET imaging tracer. It shows high accumulation in cardiomyocytes and rapid clearance from liver. We performed compartmental analysis of <SUP>18</SUP>F-FPTP PET images in rat and evaluated two linear analyses: linear least-squares (LLS) and a basis function method (BFM) for generating parametric images. The minimum dynamic scan duration for kinetic analysis was also investigated and computer simulation undertaken.</P><P><B>Methods</B></P><P><SUP>18</SUP>F-FPTP dynamic PET (18 min) and CT images were acquired from rats with myocardial infarction (MI) (<I>n</I> = 12). Regions of interest (ROIs) were on the left ventricle, normal myocardium, and MI region. Two-compartment (<I>K</I><SUB>1</SUB> and <I>k</I><SUB>2</SUB>; 2C2P) and three-compartment (<I>K</I><SUB>1</SUB>–<I>k</I><SUB>3</SUB>; 3C3P) models with irreversible uptake were compared for goodness-of-fit. Partial volume and spillover correction terms (<I>V</I><SUB><I>a</I></SUB> and <I>α</I> = 1 − <I>V</I><SUB><I>a</I></SUB>) were also incorporated. LLS and BFM were applied to ROI- and voxel-based kinetic parameter estimations. Results were compared with the standard ROI-based nonlinear least-squares (NLS) results of the corresponding compartment model. A simulation explored statistical properties of the estimation methods.</P><P><B>Results</B></P><P>The 2C2P model was most suitable for describing <SUP>18</SUP>F-FPTP kinetics. Average <I>K</I><SUB>1</SUB>, <I>k</I><SUB>2</SUB>, and <I>V</I><SUB><I>a</I></SUB> values were, respectively, 6.8 (ml/min/g), 1.1 (min<SUP>−1</SUP>), and 0.44 in normal myocardium and 1.4 (ml/min/g), 1.1 (min<SUP>−1</SUP>), and 0.32, in MI tissue. Ten minutes of data was sufficient for the estimation. LLS and BFM estimations correlated well with NLS values for the ROI level (<I>K</I><SUB>1</SUB>: <I>y</I> = 1.06<I>x</I> + 0.13, <I>r</I><SUP><I>2</I></SUP> = 0.96 and <I>y</I> = 1.13<I>x</I> + 0.08, <I>r</I><SUP><I>2</I></SUP> = 0.97) and voxel level (<I>K</I><SUB>1</SUB>: <I>y</I> = 1.22<I>x</I> − 0.30, <I>r</I><SUP><I>2</I></SUP> = 0.90 and <I>y</I> = 1.26<I>x</I> + 0.00, <I>r</I><SUP><I>2</I></SUP> = 0.92). Regional distribution of kinetic parametric images (<I>αK</I><SUB>1</SUB>, <I>K</I><SUB>1</SUB>, <I>k</I><SUB>2</SUB>, <I>V</I><SUB>a</SUB>) was physiologically relevant. LLS and BFM showed more robust characteristics than NLS in the simulation.</P><P><B>Conclusions</B></P><P>Fast kinetics and highly specific uptake of <SUP>18</SUP>F-FPTP by myocardium enabled quantitative analysis with the 2C2P model using only the initial 10 min of data. LLS and BFM were feasible for estimating voxel-wise parameters. These two methods will be useful for quantitative evaluation of <SUP>18</SUP>F-FPTP distribution in myocardium and in further studies with different conditions, disease models, and species.</P><P><B>Electronic supplementary material</B></P><P>The online version of this article (doi:10.1007/s12149-017-1171-6) contains supplementary material, which is available to authorized users.</P>

보문 : 항고혈압성 안지오텐신 전환효소 저해제를 생산하는 새로운 효모의 선별 및 저해물질 최적 생산조건

강민구 ( Min Gu Kang ),김하근 ( Ha Kun Kim ),이성훈 ( Sung Hun Yi ),임성일 ( Sung Il Lim ),이종수 ( Jong Soo Lee ) 한국균학회 2011 韓國菌學會誌 Vol.39 No.3

Forty eight strains of yeast were cultured in potato dextorse(PD) broth at 30˚C for 24 hr and centrifuged with 12,000 rpm for 20 min. After concentrated the cultures, antihypertensive angiotensin I-converting enzyme(ACE) inhibitory activities of its concentrates were investigated. Among them, the concentrates from Saccharomyces cerevisiae Y183-3 showed the highest ACE inhibitory activity of 71.8%. The ACE inhibitor from Saccharomyces cerevisiae Y183-3 was maximally produced when Saccharomyces cerevisiae Y183-3 cultured in PD broth at 30˚C for 36 hr.

Preparation and characterization of ACs/TiO2 composite electrodes for improving the specific capacitance of electrochemical double-layer capacitors.

Seo, Min-Kang,Park, Soo-Jin American Scientific Publishers 2009 Journal of nanoscience and nanotechnology Vol.9 No.12

<P>In this work, the energy storage composite electrodes were prepared by mixing activated carbons (ACs) modified with a nanosize titanium oxide (TiO2) through a means of ultrasonic vibration in ethanol solution for 30 min. We examined the cyclic voltammetry of the composite electrodes in an aqueous electrolyte, 1 M H2SO4. It was found that the specific capacitance of the composite electrodes measured in a range of 0-0.8 V was increased from 100 to 155 F/g compared to carbon electrodes comprised of activated carbon only. This was attributed to a reduction of polarization of the ACs modified by nanosized TiO2.</P>

The effects of secondary task on the control of vehicle under driving simulator: a study among 50s taxi drivers

Han Soo Kim,Jin Seung Choi,Dong Won Kang,Hong Won Yeon,Mi Hyun Choi,Doo Hwan Ji,Byung Chan Min,Soon Cheol Chung,Gye Rae Tack 대한인간공학회 2011 대한인간공학회 학술대회논문집 Vol.2011 No.5

Objective: The aim of this study is to quantitatively evaluate the effects of the secondary task during simulated driving using the variable indicating control of vehicle. Background: There are so many researches for simulated driving and performance. For instance, some researches show that the effects of cell phone conversations on simulated driving. Cell phone conversations impaired explicit recognition memory. Method: Participants included 50s taxi drivers; 15 males and 15 females. All subjects were instructed to keep a distance (30m) from the car ahead and a constant speed (80km/hr or 100km/hr). Sending text message (STM) and Searching navigation (SN) were selected as the secondary task. Experiment consisted of rest for 3min., driving alone for 1min. and driving with secondary task for 1 min.. We were analyzed anterior-posterior coefficient of variation (APCV) and medial-lateral coefficient of variation (MLCV). Results: APCV was increased by 175.4% in STM and 223.8% in SN at 80km/hr. MLCV was increased by 242.3% in STM and 323.4% in SN at 100km/hr. There was no significant difference between genders. Conclusion: Consequently, performing secondary task during driving impaired the control of vehicle.

문학관광과 노스탤지어

강준수(Jun Soo Kang),송영민(Young Min Song) 한국관광연구학회 2015 관광연구저널 Vol.29 No.5

The purpose of this paper was to examine the effects of nostalgia which make readers feel positive thinking by analyzing “Old Road to Kang-neaung.” As the nostalgic themes are emerging as a new trend, the nostalgic marketing can be applied to various areas. The paper analyzed meaning of this work, and presented the specifications and significance of Lee, Sun-won``s literature as nostalgic phenomenon. The emotional components composed of nostalgia in this work are as follows: warmth, wound, frustration, anger, resistance, and reconciliation. Although the narrator suffers from the memories of his youth even when he becomes an adult, he overcomes his wound in his younger years by transferring his memories to the nostalgia. From this point of view, this kind of nostalgic novel can have a positive effect on the mental growth of visitors who are in search of self-identity. Also this work leads visitors to experience on essential human life with a more comprehensive view by encouraging them to reflect upon their surroundings. The new form of tourism strategy is necessary to broaden people`s awareness. One of the means is utilizing literary tourism for increasing desire of tourism. The concept of space through literature is a very important key to re-invigorate nostalgia. Therefore, this paper is more meaningful in the sense that it uses ``literature`` for drawing effective nostalgia tourism. To develop Kang-neung area, the paper introduced the tour course linking the literary space of this work.

벤조디아제핀 수용체 영상용 양전자 방출 핵종 표지 플루마제닐 유도체 [F-18](3-(2-Fluoro)flumazenil의 합성과 생체 내 분포

장영수,이숙자,강삼식,홍성현,이명철,이동수,정준기,정재민,조정혁 대한핵의학회 1999 핵의학 분자영상 Vol.33 No.6

Purpose: Radiotracers that bind to the central benzodiazepine receptor are useful for the investigation of various neurological and psychiatric diseases. [C-11]Flumazenil, a benzodiazepine antagonist, is the most widely used radioligand for central benzodiazepine receptor imaging by PET. We synthesized 3-(2-[F- 18]fluoro)flumazenil, a new fluorine-18 (t1/2=110 min) labeled analogue of benzodiazepine receptor imaging agent, and evaluated in vivo for biodistribution in mice. Materials and Methods: Flumazenil (Ro 15-1788) was synthesized by a modification of the reported method. Precursor of 3-(2-[F-18]fluoro)flumazenil, the tosylated flumazenil derivative was prepared by the tosylation of the ethyl ester by ditosylethane. [F-18] labeling of tosyl substitued flumazenil precursor was performed by adding F-18 ion at 85℃ in the hot cell for 20 min. The reaction mixture was trapped by C18 cartridge, washed with 10% ethanol, and eluted by 40% ethanol. Bidistribution in mice was determined after intravenous injection Results: The total chemical yield of tosylated flumazenil derivative was ∼40%. The efficiency of labeling 3-(2-[F-18]fluoro)flumazenil was 66% with a total synthesis time of 50 min. Brain uptakes of 3-(2-[F-18]fluoro)flumazenil at 10, 30, 60 min after injection, were 2.5±0.37, 2.2±0.26, 2.1±0.11 and blood activities were 3.7±0.43, 3.3±0.07, 3.3±0.09%ID/g, respectively. Conclusion: We synthesized a tosylated flumazenil derivative which was successfully labeled with no-carrier-added F-18 by nucleophilic substitution.

Subcritical water extraction (SWE) of anthocyanin from blueberries (Vaccinium corymbosum)

Hye-Ji Kang,Seon-Woo Kim,Ha-Un Yoo,Na-Yeon Kim,So-Yoon Yee,Min-Jung Ko,Myong-Soo Chung 한국산업식품공학회 2017 학술대회 및 심포지엄 Vol.2017 No.11

Subcritical water extraction (SWE) is an eco-friendly new extraction technology because it does not contain harmful organic solvent and has high extraction efficiency in a short time compared with conventional extraction methods. Blueberries (Vaccinium corymbosum) are widely known as superfood due to rich source of anthocyanin (malvidin-3-o-galgctoside) and antioxidant activity. In this study, optimal extraction condition of SWE from blueberries was determined and compared with the conventional extraction methods. SWE was carried out using a Dionex Accelerated Solvent Extractor (ASE, Model 350) under conditions of temperatures (110, 130, 150 and 170°C) and times (1, 3, 5 and 10 min). Total anthocyanin of SWE extracts was compared with hot water (60°C, 1 h) extract and pressed juice extract. The total anthocyanin content was determined by pH differential method. Considering both the extraction time and temperature conditions, the highest content of total anthocyanin content was 0.455 mg/g FW Vaccinium corymbosum at 130°C for 3 min. At high temperature and long extraction time, the anthocyanin in the blueberries will undergo thermal degradation due to low stability of anthocyanin at extreme condition. Besides, maximum yield of anthocyanin from blueberries using SWE was about 1.2 and 3.8 times more higher than hot water extract and pressed juice extract, respectively. Therefore, SWE is faster and more efficient method to extract anthocyanin from blueberries than conventional extraction methods. This study shows a possibility of SWE applied to food processing industry.