• Title/Summary/Keyword: Surface activation

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Kinetics of 125I-BSA Binding to Monoclonal Anti-BSA Immobilized on $0.5{\mu}m$ Polystyrene Beads (c크기의 폴리스타이렌 담체에 고정화된 단세포군 항체와 항원 BSA의 속도론)

  • ;Dan
    • KSBB Journal
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    • v.11 no.2
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    • pp.225-237
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    • 1996
  • Intrinsic binding kinetics of of 125I-bovine serum albumin (125I-BSA) and immobilized monoclonal anti-BSA (MAb 9.1) were studied. Small non-porous polystyrene beads (0.5${\mu}$m diameter) were used as a solid support to minimize the mass transfer interference on rate measurements. We demonstrated both theoretically and experimentally that the binding reaction is kinetically controlled. Rate measurements show that the association reaction is of second order and the dissociation reaction is of first order. Between 4 and $37^{\circ}C$ the measured equilibrium constant agrees well with the equilibrium constant calculated from the rate measurements. The temperature effects on association are much greater than on dissociation; the activation energy for association is about 9Kca1/mole, as compared to 2Kca1/mole for dissociation. The use of small non-porous beads as a solid support in binding studies essentially avoids mass transfer limitations; such a system makes it possible to determine the intrinsic binding characteristics of any immobilized antibody on a solid surface.

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Kinetics of Catalytic Oxidation of Vinyl Chloride over CrOx/γ-alumina (CrOx/γ-alumina 촉매상에서 Vinyl Chloride의 산화반응 속도해석)

  • Lee, Hae-Wan;Kim, Young Chai;Moon, Sei-Ki
    • Applied Chemistry for Engineering
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    • v.10 no.1
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    • pp.85-92
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    • 1999
  • The complete catalytic oxidation of vinyl chloride was investigated over chromium oxide supported ${\gamma}$-alumina using a fixed bed micro-reactor at temperature between 240 and $300^{\circ}C$ and concentration between 600 and 3500 ppm. The oxidation of vinyl chloride was nonlinear in the concentration of vinyl chloride and zeroth order in the concentration of oxygen. The addition of HCl and $H_2O$ as products to the feed stream didn't influence the conversion of vinyl chloride. Several kinetic rate model were tested to describe the data over the range of condition investigated, and developed a model which provide the best correlation of experimental data. The resulting model of kinetic rate was derived by assuming that the reacting occurred via adsorption and subsequent decomposition of the vinyl chloride onto the oxygen covered chromium oxide surface, with the reaction being inhibited by the adsorption of vinyl chloride. The percent standard deviation between the predicted and experimental was about 5.2%, and the activation energy was 18.9 kcal/mol.

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The Effects of 120 Hz High Frequency Electroacupuncture on the Gastric Mucosa in Cold-Restraint Stressed Rats (고빈도 120 Hz 전침이 Cold-Restraint 스트레스 유발 흰쥐의 위점막에 미치는 영향(影響))

  • Jo, Mee-Hyeong;Ahn, Chang-Beohm;Song, Choon-Ho;Yoon, Hyoun-Min;Kim, Cheol-Hong;Jang, Kyung-Jeon
    • Korean Journal of Acupuncture
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    • v.21 no.4
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    • pp.101-115
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    • 2004
  • Objective : The present studies investigated the effects of 120 Hz high frequency electroacupuncture (EA) on the stress-induced stomach dysfunction in relation to its effect on the level of stress hormones and gastric mucosal damages. The gastric mucosal injury was induced by cold-restraint stress and two acupoints corresponding to Zusanli and Sanyinjiao in man were used. Methods : Cold-restraint stress produced typical gastric lesions in all rats of the stressed groups, but the number of ulcers as well as the mean ulcer diameter were reduced by 120 Hz EA pre-treatment. Results : The degranulation value of gastric mast cell was significantly higher in cold-restrained rats than in control ones. However, with the significant reduction of degranulation values of gastric mast cells in EA pre-treated rats compared with cold-restrained rats. Cold-restarint stress induced an elevated mRNA expression of pro-inflammatory gene such as cyclooxygenases-2 and tumor necrosis factor $(TNF)-{\alpha}$, but these expression were down-regulated in EA pre-treated rats. Immunohistochemical analysis showed that while the $inhibitory-{\kappa}B{\alpha}$ and $TNF-{\alpha}$ immunorection in the surface epithelium of the stomach tended to increase, both reactions in the EA pre-treated rats showed similar pattern as observed in controls. Conclusion : These results suggest that 120 Hz EA may act as a therapeutical means for gastric mucosal damages through an activation of pituitary adrenal system. It could be concluded that 120 Hz high frequency electroaucupuncture affords a good protective potential against stress-induced gastrointestinal dysfunction.

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Modification of Substrate Inhibition of Synaptosomal Acetylcholinesterase by Cardiotoxins

  • Ranaei-Siadat, Seyed-Omid;Riazi, Gholam-Hosein;Sadeghi, Mehdi;Chang, Long-Sen;Lin, Shinne-Ren;Eghtesadi-Araghi, Peyman;Hakimelahi, Gholam Hossein;Moosavi-Movahedi, Ali Akbar
    • BMB Reports
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    • v.37 no.3
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    • pp.330-338
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    • 2004
  • Different types of cardiotoxin (I-V and n) were isolated and purified from the venom of the Taiwan cobra (Naja naja atra). The effects of these cardiotoxins were studied on membrane-bound acetylcholinesterase, which was isolated from a sheep's brain cortex. The results showed that cardiotoxins I-III, V, and n activated the enzyme by modification of substrate inhibition, but cardiotoxin IV's reaction was different. The inhibition and activation of acetylcholinesterase were linked to the functions of the hydrophobicity index, presence of a cationic cluster, and the accessible arginine residue. Our results indicate that Cardiotoxins have neither a cationic cluster nor an arginine residue in their surface area of loop I; therefore, in contrast to fasciculin, cardiotoxins are attached by loop II to the peripheral site of the enzyme. As a result, fasciculin seems to stabilize nonfunctional conformation, but cardiotoxins seem to stabilize the functional conformation of the enzyme. Based on our experimental and theoretical findings, similar secondary and tertiary structures of cardiotoxins and fasciculin seem to have an opposite function once they interact with acetylcholinesterase.

The Comparison of Electromyographic Ratio of Serratus Anterior and Upper Trapezius According to Exercise Position and Shoulder Flexion Angle during Scapular Protraction Exercises (어깨뼈 내밈 운동 시 운동 자세와 어깨관절 굽힘각도에 따른 앞 톱니근과 위 등세모근의 근 활성도 비의 비교)

  • Koh, Eun-Kyung;Weon, Jong-Hyuck;Jung, Do-Young
    • Korean Journal of Applied Biomechanics
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    • v.22 no.2
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    • pp.193-199
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    • 2012
  • The purpose of this study was to investigate the activities of the serratus anterior (SA) and upper trapezius (UT) muscles during scapular protraction exercise with a dumbbell. Twenty-one healthy subjects with no medial history of shoulder pain or upper extremity disorders were recruited for this study. Subjects performed scapular protraction at $90^{\circ}$ and $130^{\circ}$ shoulder flexion with a dumbbell in supine and standing positions. The activities of the SA and UT were measured via surface electromyography (EMG) during 4 scapular protraction exercises. A 2 (angle) ${\times}$ 2 (position) repeated-measures analysis of variance (ANOVA) was used to compare the normalized activities of the SA and UT and the UT/SA ratio. The results showed that activities of both the SA and UT were the highest for the scapular protraction exercise at $130^{\circ}$ shoulder flexion in the standing position. However, the UT/SA ratio was the lowest for the exercise at $90^{\circ}$ shoulder flexion in supine position. Therefore, for selective activation of the SA muscle, we recommend performing the scapular protraction exercise with a dumbbell in the supine position at $90^{\circ}$ shoulder flexion.

Hemagglutinative Activity of Lectin Isolated from Shiitake, Lentinula edodes (표고버섯에서 분리한 렉틴의 적혈구 응집활성)

  • Kim, Young-Shin;Lim, Chi-Hwan;Cho, Nam-Seok
    • The Korean Journal of Mycology
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    • v.30 no.1
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    • pp.31-36
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    • 2002
  • Since lectin condense more easily cancer cell than normal cell, it has been investigated very actively. Recently, a lot of researchers gave attention to lectin in natural products especially because lectin has effects on T-cell activation and anticancer activity, and specificity on polysaccharide. The specificity is useful to confirm kind of polysaccharide of the cell surface and to study the polysaccharide. In this research, we purified lectin from shiitake, Lentinula edodes, and then characterized it. The molecular weight of the lectin was 23 kDa, and it was stable only under the $40^{\circ}C$ and in a alkaline solution. As for the specificity of polysaccharide, the lectin had specificity on galactose, fucose, glucose, lactose and N-acetyl-D-galactosamine. In addition, it was confirmed to be a glycoprotein.

Effect of Visual and Palpation Feedback on Muscle Activity of Gluteus Maximus and Motion of Pelvic Rotation during Clam Exercise (크램 운동 시 시각-촉진 되먹임이 큰볼기근 활성도와 골반 회전에 미치는 영향)

  • Koh, Eun-Kyung;Jung, Do-Young
    • The Journal of Korean Physical Therapy
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    • v.25 no.5
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    • pp.337-342
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    • 2013
  • Purpose: This study was conducted in order to determine the effect of visual and tactile feedback on muscle activity of the gluteus maximus (Gmax) and abdominal muscles and the motion of pelvic rotation during performance of clam exercise (CE). Methods: Thirteen subjects without low back pain were recruited for this study. Each subject was instructed to perform the CE without and with feedback. The subjects were instructed to keep pelvic from rotating backwards by palpating the ASIS and monitoring the pelvic movement by themselves during performance of CE with feedback. The electromyographic (EMG) activities of Gmax and abdominal muscles were collected using surface EMG. Angles of pelvic rotation were measured using a 3-dimensional motion-analysis system. Paired t-tests were used for comparison of EMG activities in each muscle and the angle of pelvic rotation. Results: The EMG activities of all abdominal muscles were not significant between CM without and CM with feedback (p>0.05). The EMG activity of Gmax was significantly greater in CM with feedback compared with CM without feedback (without vs. with feedback; 14.2% vs. 20.7%MVIC) (p<0.05). The angle of pelvic rotation was significantly less in CM with feedback compared with CM without feedback (without vs. with feedback; $15.3^{\circ}$ vs. $10.8^{\circ}$ ) (p<0.05). Conclusion: Therefore, these findings suggest that CM with the visual and tactile feedback is effective in activation of the Gmax and correcting of the uncontrolled lumbopelvic rotation during CE.

Effect of Shoulder Position on Scapular Muscle Activity during Scapular Protraction

  • Yun, Sung Joon;Kim, Moon-Hwan;Weon, Jong-Hyuck
    • The Journal of Korean Physical Therapy
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    • v.32 no.3
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    • pp.157-162
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    • 2020
  • Purpose: This study was to evaluate several tasks performed at a high intensity in terms of their ability to elicit EMG activity in the serratus anterior by comparing the EMG activities of the serratus anterior, upper trapezius, and lower trapezius muscles during six tasks combined shoulder flexion with rotation. Methods: Fifteen healthy males were recruited to this study. Each subject was instructed to assume a sitting position without back support and asked to flex (90° or 120°) the right shoulder and protract the scapula in the sagittal plane with maximal external rotation; to assume a neutral position; or to internally rotate the glenohumeral joint. The EMG data were collected from the serratus anterior (SA), upper trapezius (UT), and lower trapezius (LT) muscles were normalized to maximum voluntary isometric contraction. The UT/LT and UT/SA muscle activity ratios in each task were assessed by calculating the surface EMG. Data were analyzed by two-way repeated-measures analysis of variance, with the level of significance set at p<0.05. Results: The results of this study, shoulder flexion with external rotation resulted in low upper trapezius/serratus anterior and upper trapezius/lower trapezius ratios and a relatively high level of serratus anterior activation. Conclusion: Shoulder flexion with external rotation used herein may be considered as important for clinical interventions aimed at selectively increasing SA strengthen and clinical selection of exercises for improving glenohumeral joint and scapulothoracic control.

Fabrication and Electrical Properties of Conductive Carbon Black filled Poly(Vinyliden Fluoride) Composite (도전성 카본블랙/PVdF 복합재의 제조 및 전기적 특성)

  • Kim, Myung-Chan;Moon, Seung-Hwan;Lim, Jae-Seok;Hahm, Hyun-Sik;Park, Hong-Soo;Kim, Myung-Soo
    • Journal of the Korean Applied Science and Technology
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    • v.20 no.3
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    • pp.212-220
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    • 2003
  • Electrical properties of carbon filler/PVdF [poly(vinylidene fluoride)] composite were investigated as a funtion of carbon filler/PVdF ratio in the range of 0.2${\sim}$0.5. Three kinds of comercialzied conductive carbon blacks such as Hiblack 41Y, KE300J, and KE600J, and carbon nanofibers prepared by the catalytic chemical vapor deposition of $C_2H_4$ over Ni-Cu catalysts were used as the carbon fillers. The electrical conductivity of carbon filler/PVdF composites were in the range of 0.65 to 13.5 S/cm depending the fillers' electrical conductivity ranging from 5.6 to 23.1 S/cm. Among the carbon fillers used, the KE600J carbon black showed the highest conductivity both in the composite and filler itself because of its high degree of graphitization due to the high-temperature thermal treatment and its high surface area due to the activation treatment.

Characteristics of Balance and Muscle Activation responded to Dynamic Motions in Anterior-Posterior and Medial-Lateral Directions (전후방 및 내외측 방향의 동적 움직임에 따른 균형 및 근육 활성도 특성)

  • Kim, ChoongYeon;Jung, HoHyun;Lee, BumKee;Jung, Dukyoung;Chun, Kyeong Jin;Lim, Dohyung
    • Journal of Biomedical Engineering Research
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    • v.34 no.4
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    • pp.212-217
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    • 2013
  • Falling is one of the major public problems to the elderly, resulting in limitations of daily living activities. It can be induced by the functional loss of the balance ability and muscle strength in the elderly. It has been, however, not well investigated to suggest an effective methodology improving the balance ability and muscle strength for the prevention of the falling due to lack of information about the characteristics of the balance and muscle activations responded to the dynamic motions. The aim of the current study is, therefore, to identify the characteristics of the balance and muscle activations responded to the dynamic motions in Anterior-Posterior(AP) and Medial Lateral(ML) directions. For that, a motion capture system with eight infrared cameras, surface electromyogram system and Wii Fit system with a customized variable unstable base were used and kinematic and kinetic data obtained from the systems were analyzed for five healthy male($24.8{\pm}3.3years$, $177.4{\pm}2.0cm$, $73.9{\pm}12.9kg$, $23.5{\pm}4.0kg/m$). The results showed that the characteristics of the balance and muscle activations were differently responded to between the dynamic motions in Anterior-Posterior(AP) and Medial Lateral(ML) directions. These findings may indicate that customized dynamic motions should be applied to the training of the balance ability and muscle strength for the effective prevention of the falling. This study may be meaningful to providing basic information to establish a guideline improving effectively the balance ability and muscle strength.