• Journal of Biomedical Engineering Research
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• v.27 no.5
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• pp.267-273
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• 2006

Numerical analysis was performed on the enzyme transport and the flow fields in order to predict the effectiveness of urokinase injection regimens in clot dissolution. The species and momentum transport equations were numerically solved for the case of uniform perfusion of enzyme into a fibrin clot for an arterial thrombus and a deep vein thrombus models. In order to predict the thrombus lysis efficiency of continuous and forced intermittent injections, enzyme perfusion and clot lysis were simulated for the different injection velocities. Intermittent injection showed faster clot lysis compared to continuous perfusion, and lysis efficiency was increased as injection velocity increased.

• Preventive Nutrition and Food Science
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• v.4 no.1
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• pp.79-83
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• 1999

A potentiometric biosensor employing a CO3-2 ion-selective electrode(ISE) and malic enzyme immobilization in al flow injection analysis (FIA) system was constructed. Analytical parameters were optimized for L-malate determination . The CO3-2 -ISE-FIA system was composed of a pump, an injector, a malic enzyme (EC1.1.1.40) reactor, a CO3-2 ion-selective electrode, a pH/mV meter and a recorder. Cofactor NADP was also injected with substrate for theenzyme reaction into the system. Optimized analytical parameters for L-malate determination in the CO3-2 ISE-FIA system were as follows ; flow rate, 14.5ml/hr ; sample injection volume, 100ul; enzyme loading in the reactor, 20 units ; length of the enzyme reactor , 7 cm ; tubing length form the enzyme reactor to the detector as a geometric factor in FIA, 15 cm . The response time for measuring the entire L-malate concentration range (10-2 ~10-5 mol/L ; 4 injections )was <15minutes . In this CO3-2 -ISE-FIA system, the potential differences due to th eformation of CO3-2 by the reaction of malic enzyme on L-malate were correlated to L-malate concentration in the range of 10-2 ~10-5mol/L ; the detection limit was 10-5 mol/L. This potentionmetric CO3-2 ISE--FIA system was found to be useful for L-malate measurement.

• Archives of Pharmacal Research
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• v.23 no.6
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• pp.548-553
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• 2000

Two drug-enzyme conjugates of dexamethasone-subtilisin and dexamethasone-cellulase have been synthesized and characterized to study their drug-protein incorporation ratio, immunoreactivity, enzyme activity and stability and these studies proved that a variety of drug enzyme conjugates could also be synthesized and characterized.

• Preventive Nutrition and Food Science
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• v.3 no.1
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• pp.36-42
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• 1998

Ion-selective eleltrodes(ISEs) are simple electrodechemical devices for the direct measurement of ions in the samples. A novel potentiometric biosensor for the determination of L-Malate or D-isocitrate has been developed by using CO2-3 -ISE-FIA system was composed of a pump, an injector, a malic enzyme or isocitric dehydrogenase enzyme reactor, a CO2-3 -ISE, a pH/mV meter, and an integrater. The various factors, such as buffer capacity types of plstericizer and polymer, were optimized for the CO2-3 selectivity. In this novel CO2-3 --ISE-FIA system, the potential difference due to the amount of CO2-3 produced from each enzyme reaction was proportional to the amount of L-malate or D-isocitrate.

• BMB Reports
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• v.31 no.3
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• pp.296-302
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• 1998

A potentiometric flow injection biosensor for the analysis of anti-cholinesterases (anti-ChEs), based on inhibition of enzyme activity, was developed. The sensor system consists of a reactor with acetylcholinesterase (AChE) immobilized on controlled pore glass and a detector with an $H^{+}-selective$ PVC-based membrane electrode. The principle of the analysis is based on the fact that the degree of inhibition of AChE by an anti-ChE is dependent on the concentration of the anti-ChE in contact with AChE. The sensor system was optimized by changing systematically the operating parameters of the sensor to evaluate the effect of the changes on sensor response to ACh. The optimized biosensor was applied to the analysis of paraoxon, an organophosphorus pesticide. Treatment of the inhibited enzyme with pyridine-2-aldoxime fully restored the enzyme activity allowing repeated use of the sensor.

• Journal of Radiation Protection and Research
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• v.18 no.2
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• pp.61-69
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• 1993

We examined various enzyme activity changes by intraperitoneal injection uranium in the carp liver. These enzyme activity changes can be used as biochemical indicators of internal exposure to uranium. The results were followings ; 1) Total protein concentration decreased by intraperitoneal injection in the carp liver. 2) Lysosomal acid pretense and ${\beta}-glucuronidase$ activities increased in the liver until sixth intraperitoneal injection of uranium, but Lysosomal acid phosphatase activities decreased in the liver until the sixth injection of uranium. 3) Alkaline phosphatase activities sharply increased and Glutamate oxaloacetate Transaminase activities steadily decreased in the liver until the sixth injection of uranium. 4) Creatine %kinase activities steadily decreased and malate dehydrogenase activities sharply decreased in the liver after the primary injection of uranium. Any malate dehydrogenase activities was not detected after sixth injection of uranium.

• Fisheries and Aquatic Sciences
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• v.18 no.2
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• pp.229-233
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• 2015

We developed a new softening technology applicable to the main body of the jumbo squid Dosidicus gigas; this will aid in squid consumption by elderly individuals and those who have masticatory and dysphagia problems. Protease solutions were injected into jumbo squid and hardness was measured using a texture analyzer. Seven enzymes were tested. Jumbo squid became progressively softer during bromelain and collupulin treatment; the hardness attained $5.6{\times}10^3N/m^2$ at bromelain concentrations of 1.00% (w/v) and $6.7{\times}10^3N/m^2$ at collupullin concentrations of 1.00% (w/v). The extents of tissue softening after bromelain and collupulin injection to 0.1%, 0.25%, 0.50%, and 1.00% (all w/v) were evaluated; the squid retained its shape after steaming for 10 min at $100^{\circ}C$ to inactivate the enzymes. Thus, the results of this research indicate that enzyme injection softens the texture of jumbo squid.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.3
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• pp.874-879
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• 2004

Alakaline phosphatase (ALP)- or horseradish peroxidase (HRP)-antibody conjugate was used frequently on the immunological detection methods such as enzyme-linked immunosobent assay (ELISA), immunobolt, immunohistochemistry. The classical enzyme-antibody coupling method by one-step (direction) injection of glutaraldehyde bring into being disadvantage such as low sensitivity of antigen detection because of homopolymers. This study was modified with the dialysis glutaraldehyde method to provide simple coupling through E-amino residues present in most protein. The dialysis glutaraldehyde coupling effects were better than the classical one-step glutaraldehyde injection in antigen detection of ELISA and immunobolt. Optimal dose of the dialysis glutaraldehyde solution was 0.10-0.25 %. This results suggest that the dialysis glutaraldehyde coupling method can readily applied to antigen detection of in vitro and in vivo.

• Korean Journal of Poultry Science
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• v.16 no.4
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• pp.219-232
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• 1989

The present study was done to investigate the mechanism of Pancreatic digestive enzyme secretion in response to dietary components in chicks. A simplefied pancreatic juice collection method, useful for a short-term experiment, was developed. By wing vein injection, it was shown that the increased trypsinogen and chymotrypsinogen, while neither other single amino acids nor glucose affected the secretion of enzymes, amylase, trypsinogen and chymotrypsinogen. Cholecystokinin (CCK) had an immediate effect on pancreatic enzyme secretion and this response was in a dose dependent fashion. The injection of CCK seemed to have selective stimulation favoring the secretion of chymotrypsinosen followed by amylase and trypsinogen. Simultaneous injection of single amino acid with CCK increased digestive enzyme secretion to various extents depending on the kind of amino acids whereas the injection of glucose with CCK did not affect when compared with that of CCK'alone. By varying doses, synergetic action of CCK plus amino acid on the secretion of pancreatic digestive enzymes was observed at 0.5mM for Val and 5mM for Arg. A further attempt was made to examine the effect of combined administration of amino acids with CCK on pancreatic enzyme secretion. The injected substances were an AAs mixture and combination of selected amino acids, i.e. Thr＋Phe＋Ile, Thr＋Phe. Thr＋Ile or Phe＋Ile. When increases in enzyme outputs for the first 30 min were compared , it was shown that the responses of three enzymes, amylase, trypsinogen and chymotrypsinogen, brought about by the administration of the AAs mixture was almost entirely accounted for by the combined injection of Thr＋Phe. Thus, it was well demonstrated that CCK and amino acids had a synergetic action on the secretion of a specific pancreatic digestive enzyme depending on a kind of amino acid injected.

• International Journal of Vascular Biomedical Engineering
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• v.4 no.2
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• pp.13-18
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• 2006

Direct injection of a fibrinolytic agent to the intra-arterial thrombosis may increase the effectiveness of thrombolysis by enhancing the permeation of thrombolytic agents into the blood clot. Permeation of fibrinolytic agents into a clot is influenced by the surface pressure, which is determined by the injection velocity of fibrinolytic agents. Computational fluid dynamic methods were used in order to predict clot lysis for different jet velocities and nozzle arrangements. Firstly, thrombolysis of a clot was mathematically modeled based on the pressure and lysis front velocity relationship. Direct injection of a thrombolytic agent increased the speed of thrombolysis significantly and the effectiveness was increased as the ejecting velocity increased. The nine nozzles model showed about 20% increase of the lysed volume, and the one and seventeen nozzles models did not show significant differences. Secondly, thrombolysis was modeled based on the enzyme transport and the fluid flow equations, and quasi steady numerical analysis was performed. Clot lysis efficiency was also increased as injection velocity increased.