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[in Japanese]
1996 Volume 25 Issue 3 Pages
513
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
JOURNAL
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T. SHIROYAMA, T. AKAMATSU
1996 Volume 25 Issue 3 Pages
515-521
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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We have been developing a nutating cetrifugal blood pump, so called Tea-Spoon Pump (TS-pump), which avoids the sealproblem of conventional centrifugal blood pump. We investigated the pump performance and pressure fluctuation near the pump-outlet of Double-Impeller Type (type TS-II) compared with an old-type (Single-Impeller, TS-I). The pump pressure and efficiency of thetype TS-II Were higher than the type TS-I, and pressurefluctuation (attribute to hemolysis) in the TS-II was lower than that in the TS-I. Also, pressure fluctuationin case of Lacked-Impeller was lower than in case of Normal-Impeller. Various kinds of pump casing of TS-II Were tested; Circular type (C1), Spiral type (S1), 2 way-outlet Circular type (C2), 3 Way-outlet Circular type (C3). Type C3 proved to have high pump performance and low pressure fluctuation.
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-CHARACTERISTIC TEST OF THE ACTUATOR WITH A METALLIC SLIDER-
N KABEI, K. TSUCHIYA
1996 Volume 25 Issue 3 Pages
522-526
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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We have been developing an electrostatic linear actuator for use as an artificial cardiac muscle which consists of parallel plate capacitors and a slider made of dielectric material. In this study, a metallic slider was proposed for easy manufacturing of the slider and examined the output characteristics of the actuator with it. The maximum static force of approximately 8mN was generated by the actuator under the driving voltage of 300V. The driving system, which can drive the slider continuously for long distance, was developed. Length of an electrode of the stator was 1mm. Space between two electrodes was 0.1mm. Thickness of the slider was 0.3mm and width was 40mm. The liquid crystal GR-63 was used asthe gap-filling medium. The slider was moved smoothly under the driving voltage of 200V and the driving frequency of 100Hz. The maximum speed was 2.5mm/s. These value were almost equal to those obtained by the actuator with slider made of dielectric material.
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A. ISHIKAWA, M. YOSHIZAWA, A. TANAKA, K. ABE, T. YAMBE, S. NITTA
1996 Volume 25 Issue 3 Pages
527-533
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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The authors have previously shown that the desired value of stroke volume can be achieved with minimum driving energy by driving a sac-type air-driven artificial heart at the optimal operating point (OOP). When stroke volume is plotted against systolic duration, the resulting curve forms a triangle with the systolic duration axis as its base. The OOP is the operating point at the apex of the triangle and is opposite the base. The conventional algorithm for automatic maintenance of the OOP utilized the time (z[ms]) when the outflow rate (f (t) [L/min]) changes from positive to zero. This causes the following defects: 1) susceptibility to noise in the f(t); and 2) difficulty in determining the correction factor included in the algorithm. To overcome these defects, the present study proposes a new algorithm for determination of the OOP on the basis of the time (p[ms]) maxmizing f(t) value during the same beat, instead of z. Experiments carried out in a mock circulatory system have shown that the new algorithm works in a satisfactory manner.
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Toyoda YOSHIYA, Okada MASAYOSHI, Kashem MOHAMMEDABUR, Tsukube TAKURO, ...
1996 Volume 25 Issue 3 Pages
534-537
Published: June 15, 1996
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Effect of dynamic cardiomyoplasty on chronic heart failure; An experimental study To clarify the hemodynamic effect of dynamic cardiomyoplasty (DCMP) on chronic heart failure, we performed cardiomyoplasty for canine chronic heart failure models induced by aorto-inferior vena caval shunt, femoral arterio-venous shunt, or intracoronary infusion of Adriamycin. The effect of DCMP was assessed by echocardiography and cardiac catheterization. During operation of cardiomyo plasty, the right & left ventricular, aortic, and pulmonary arterial pressures were increased with activating RCMP. Under continuous stimulation after preconditioning using cardiomyostimulator, intracardiac pressures were not changed with activating DCMP, but fractional shortening of the left ventricle and cardac output were augmented by RCMP. We concluded that DCMP had a modest effect of augmentation on cardiac systolic function.
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K ARAKI, T NAKATANI, K TODA, Y TAENAKA, [in Japanese], M. OSHIKAWA, T. ...
1996 Volume 25 Issue 3 Pages
538-541
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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Several types of skeletal muscle pump system with an actuator of the latissimus dorsi muscle (LDM) in linear configuration, have been reported. In this study, the power of the LDM was estimated in animal experiments, and the feasibility of a linear-skeletal muscle pump system was investigated based on the muscular property. To evaluate the power, in-situ LDMs in three adult goats received 12-week preconditioning (PC), followed by power analysis. The insertion of LDM was dissected and connected to a tension and a displacement transducer. During 120-minute contraction, tension-length relationships were obtained at 0, 60 and 120 minutes, and the maximum external power (maxP;Watts/kg muscle weight) was estimated. Good fatigue resistance and the highest maxP of 3.16 Watts/kg at 120 minutes was derived from preconditioned LDM. Assuming that the weight of human bilateral LDMs is 0.5 kg, estimated power became 1.58 Watts. If the system is applied to left ventricular assistance (stroke volume: 70ml, 50bpm, 0.78 Watts), the efficiency of the system should be more than 50%. To realize the linear-skeletal muscle pump system, much effort should be make to decrease the power loss.
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H. NAKAJIMA, Y. OGURA, J. ANBE, Y. EGOH, T. AKASAKA, S. KANEKO, H. AND ...
1996 Volume 25 Issue 3 Pages
542-547
Published: June 15, 1996
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The electric characteristicof the newly designed surfaceelectrodes(SE), a peripheralnerve cathode and an epimysial anode, fordynamic cardiomyoplasty was compared with the conventional intramuscularelectrode (IME) using six dogs. The epicardial electrode (model 325452: Telectronics ) was used as the peripheral nerve cathode. The 10cm long of the bare lead at the end part of the pacing lead (model 4505 Medtronic) was as the epimysial anode. Stimulation threshold and lead impedance were measured. Threshold of SE (average 0.7V) was a half ofIME, and impedance (802Ω) was 3 times of IME. The contraction forcewas measured stimulating with the voltage of two times of the threshold. The contraction pattern and the conduction velocity were observed. No diference betweenSE and IME was found. Conclusion: In contrast to the IME, SE gives only the slight mechanicaldamageto muscle fibers, nerves and vessels. The electricaldamageofSE is also less than IME, becauseSE candrive a muscle by a one-20th electricenergy that IME needs. The use of SE would prevent the degeneration of the muscle.
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Y. SAKUMA, M. SHIONO, S. SHINDO, K. AKIYAMA, Y. ORIME, H. HATA, S. YAG ...
1996 Volume 25 Issue 3 Pages
548-552
Published: June 15, 1996
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Comparison study of pneumatic VAD and PCPS. In past 13 years, we had 16 pneumatic ventricular assist device (Group-I) and also 16 percutaneous cardiopulmonary support patients (Group-II), as a cardiac support for postcardiotomy cardiogenic shock. Using those patients, comparison study was performed, examing drainage volume, haemolysis, intubation time and weaning rate. Drainage volume were much in the Group-I during assist. Platelet count decreased early after assist in the group-II. There were no differences in haemolysis between the two groups. Early extubation and primary sternal closure were possible in the Group-II. Weaning rate of Group-I was better than that of Group-II, however survival rate of Group-II was better than that of Group-I. In the PCPS cases that obtained enough assist flow, there were few cases complicated with multiple organ failure (MOP). In case of post-cardiotomy cardiogenic shock or low output syndrome, PCPS system should be applied firstly under IABP assist become of its simplicity and low cost. Thereafter, VAD should be used in case of refractory to PCPS and more longer support duration.
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Y HORI, Y YAMADA, Y KANASAKI, Y KISHIZOE, T NAKATANI, Y SASAKO, K KUMO ...
1996 Volume 25 Issue 3 Pages
553-559
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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Striving to achieve better postoperative rehabilitation in patientsundergoing long-term circulatory supportusing a ventricular assist system, we have performed kinesitherapy in 6 patients since 1994. Statistical analyses were established, calculating a Spearman's correlation coefficient by ranks, whether the earlier introduction of such kinesitherapy could be advantageous so as to expand the activity of daily life and to minimize undesirably stiff joints of the extremities. Longer duration of the sedated period proved to be significantly related (P<0.05) to poorerpostoperative movement, as well as severer stiffness, of the arms. Earlierintroduction of flexing and stretching of the joints, in contrast, was likely the favourable factor for better activity of the patients on their beds. Passive movements of the extremeties for adduction, abduction, and medial and lateral rotation were employed in 4 patients subsequent to the expiry of thesedated term, these therapy being obviously of clinical use to avoid stiff joints. It is concluded, therefore, that earlier introduction of functional therapy to the bodily joints should be important so as to provide better quality of life during circulatory support. Although such rehabilitation could be effective under sedated condition, shorter duration of the sedated period, if applicable, would berecommended.
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M AOKI, H SIOZAWA, Sato KAZUYUKI, Sato KOICHI, C TAKAYAMA, S KYO, R. O ...
1996 Volume 25 Issue 3 Pages
560-565
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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Three dilative cardiomyopathy (DCM) patients with long term support with left ventricular assist systems (LVAS) received physical rehabilitation following our rehabilitation programs. All patients were male and the average age was 45 year-old. Two patients were supported by Toyobo LVAS (NCVC type) and another were supported by TCI-LVAS (Heart Mate1000IP). The average duration of complete bed-rest before LVAS implantation were 30 days. Rehabilitation program was consisted of 5 stages. It is scheduled to start with physical training on the bed from 3POD, beside the bed from SPOD, using bicycle ergometer from 8POD, and walking assisted by a walker from 10POD after LVAS implantation. Three patients could satisfactorily complete the rehabilitation program until the level of bicycle ergometer, however, the start of walking training was significantly delayedto 17POD due to weakness of the legs resulting from the long duration of bed-rest before LVAS implantation. In conclusion, the rehabilitation program for patients who were supported by LVAS should be planned and individually arrangedregarding the physical ability of each patient.
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S. MURATA, T. INO, H. ADACHI, A. MIZUHARA, A. YAMAGUCHI, H. KAMIO, K. ...
1996 Volume 25 Issue 3 Pages
566-570
Published: June 15, 1996
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To overcone hemorrhage complications during extracorporeal circulatory support, we introduced the newly developed heparin-coated PCPS (CPS-HP, Terunro Inc.) and evaluated its efficacy. The CPS-HP was tested in 10 patients (postcardiotony shock in 5 patients, AMI in 3, and acute fluminant nyocarditis in 2). During the support, low dose heparin was adninistered continuously to maintain ACT around 150 sec. Four patients (40%) were weaned fromPCPS, and 3 patients (30%) are long termsurvivors. Two cases were weaned after over 200 hours support without exchanging the CPS-HP system Although administered heparin dose was 156±84U/hour, there was no thromboembolic nor hemorrhagic complications during the support in all cases. In previous heparin coated PCPS system (Carnnda Bioactive Surface®) in our hospital, 4 of 24 cases caused plasma leakage of the oxygenator. But there was no plasixa leakage in CPS-HP oxygenator. And also life tine of the CPS-HP oxygenator was significantly longer than that of the Carmeda coating system (CPS-HP; 98±93 vs. Carmeda; 14±13 hours, p<0.05). In conclusion, these result suggest the good durability and efficacy of the CPS-HP for long term temporary support.
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A SAITO, T NAKAYAMA, H MORO, H OHZEKI, J HAYASHI, S. EGUCHI
1996 Volume 25 Issue 3 Pages
571-575
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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We evaluated a bypass tubing coated on its luminal surfaces with Microdomain F-μ (MDF-μ), which has microdomain structures and has been supposed to suppress platelet adhesion and activation. Six hours of venoaretrial bypass under minimal systemic heparinization was performed using MDF-μ coated bypass tubings in 3 pigs (M group). No coated tubings were also evaluated in 3 pigs (C group) as the control. There were no significant differences in hematologic parameters (platelet count and fibrinogen, fibrinopeptide A, and thrombin-antithrombin III complex levels) between the two groups. No thrombus formation was observed in M group during the experimental periods. Only mild attachment of red blood cells and platelets were found on the surfaces by scanning electron microscopy in M group. On the other hand, thrombi were observed at inflow tubings in C group. The present study revealed that a venoarterial bypass tubings coated with MDF-μ showed improved antithrombogenicity compared with the control, although there were no significant differences in changes of systemic coagulation parameters during the experiment.
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T. NAKATANI, H. TAKANO, E. SASAKI
1996 Volume 25 Issue 3 Pages
576-581
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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We have developed a motor-driven implantable left ventricular assist system. This system consists of a pusher-plate type pump and a spline actuator driven by a DC brushless motor. A pump housing was made of epoxy-resin and a diaphragm was made of segmented- polyurethane (TM-5). The diameter of the model 1 was 85mm, 76mm in depth and 900 gram of weight. The actuator showed good durability (up to 300 days) in unloading status. In mock circulation, the model 1 showed 2.6l/min of output in 20mmHg of preload and 80mmHg of afterload. We changed the configuration of the pump and the motor design in model 2. New model showed 7.6l/min of output in mock circulation. This system is promising to the new implantable LVAS.
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[in Japanese], Robert JARVIK, Michael P. MACRIS, John L. ROBINSON, Ste ...
1996 Volume 25 Issue 3 Pages
582-585
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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Intraventricular axial flow blood pumps, Jarvik 2000 designed for long term left ventricular assist, were implanted in seven calves. Six calves have survived for 63 to 162 days (mean 110 days). One study is ongoing at 74 days. The causes of termination of study were broken electrical wire in one case, thrombus at rotor/stator junction in one case, impeller blade/casing rubbing in three cases and obstruction of outlet conduit in one case. Plasma free hemoglobin and other laboratory data were observed in normal range. No damage of myocardium and no renal infarction were observed after over five month survival.
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K. KAWACHI, K. MIZUGUCHI, T. KAWATA, S. KOBAYASHI, Y. HAMADA, K. NIWAY ...
1996 Volume 25 Issue 3 Pages
586-589
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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In vivo valve function of the artificial valve in patients with St. Jude Medical (SJM) valve and Bicer prosthesis in the aortic position was evaluated both at rest and during exercise after surgery. Effective orifice area was obtained with use of the Gorlin formula. Transaortic pressure gradient was obtained from Gorlin formula in each body surface area.
For 21mm SJM valve, transaortic pressure gradient with body surface area 2.0m
2 was 9mmHg at rest and 19mmHg during exercise. For 21mm Bicer valve, transaortic pressure gradient with body surface area 2.0m
2 was 14mmHg at rest and 19mmHg during exercise. From these results it is considered that SJM valve and Bicer valve for the 21mm valve are available in the aortic position.
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T. SHIMOOKA, S. MURABAYASHI, Y. MITAMURA, T. YUHTA
1996 Volume 25 Issue 3 Pages
590-595
Published: June 15, 1996
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The accelerated fatigue testers, which involve compliant structures in the pipe wall near the tested valve, was developed. And effect of the compliance on pitting of a leaflet was evaluated. As a preliminary test, duralumin disks were used. Tests run in 600 cycles/min. for 15h. In all cases, few pits were observed on the outflow side surface of disks but a lot of pits on the inflow side of those. The number, size and depth of pits were clearly (more than twice in many areas) increased by the existence of the wall compliance. It is suggested a compliance could cause severe cavitation erosion. Compliant structure must be account for design of accelerated fatigue tester from the view of cavitation erosion. Keywords: Artificial heart valve, Cavitation erosion, Accelerated fatigue tester, Compliant structure
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K. KUWAKI, T. ABE, K. KOMATSU, R. KOSHIMA, S. KOMATSU
1996 Volume 25 Issue 3 Pages
596-598
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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Early Clinical Results of BICARBON Valve Prosthesis. From January 1994 to July 1994, twenty patients underwent cardiac valve replacement with the BICARBON (BC) valve prosthesis. We implanted 10 BC prostheses in aortic, 11 in mitral, 1 in tricuspid position. Neither operative mortality nor late mortality were recognized with a mean follow-up of 18.4 months. Two patients required the reoperation. One of them underwent reMVR with SJM valve because of paravalvular leakage following MVR, another patient underwent re-operation where the direction of the implanted prosthetic valve hinge was changed due to interference with prosthetic valve motion by the preserved posterior mitral leaflet. Structural deterioration, thromboembolism, anticoagulant-related hemorrhage and prosthetic valve endocarditis were not recognized. Peak pressure gradient in aortic and mitral position and effective mitral orifice area were maintained within normal ranges as compared with the SJM valves by Doppler echo cardiography. Valve opening and closing angles revealed no abnormality by cinefluoroscopy. Postoperative hemodynamics were improved following surgery and serum LDH as parameter for hemolysis was maintained within normal ranges. These studies indicated that the early clinical results with the BC valve were satisfactory, although the further long term follow-up studies will be required.
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Masaaki KOGA, Hitoshi TOYOHIRA, Hideaki SAIGENJI, Akihiro YAMAOKA, Hir ...
1996 Volume 25 Issue 3 Pages
599-602
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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Mid-term Results of Valve Replacements with Omnicarbon Prosthetic Valves. One hundred and seven patients who underwent valve replacement with Omnicarbon valves were analyzed according to the guideline of STS-AATS (1988). There are thirty three aortic valve replacement, sixty one mitral valve replacement and thirteen double valve replacement. They consist of 59 male and 48 female with a mean age of 56.5 years old. The operative death was found in 8 patients (7.5%), caused by ruptured left ventricle in two, low output syndrome in two, and cerebral bleeding in two patients, and graft versus host disease due to blood transfusion in one and ventricular arrhythmia in one. The late death was seen in ten patients (9.3%). The causes of the late death included five cerebrovascular disorders, two advanced heart failures, one prosthetic valve endocarditis, one arrhythmia, and one ileus. The overall survival rate is 78.5% at 5.8 years, the survival rate of AVR is 85.2%, MVR 76.4% and AVR+MVR 69.2% at 5.8 years respectively. The event-free rate of survivors is 89.0% at 5.8 years and freedom from all valve-related mobidity and mortality is 80.0% at 5.8 years. The result of this study revealed that the Omnicarbon valve had low rate of valve related complications.
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-RELATION BETWEEN VALVE FLOW AND OPENING ANGLE OF THE OCCLUDER
H. KAJIWARA, K. HIRANO, T. HAMADA, N. HASHIYAMA, M. OKAMOTO, S. SATOH
1996 Volume 25 Issue 3 Pages
603-606
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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The function of the Omnicarbon cardiac(OC) valve was evaluated in 36 aortic valve replacement patients by cineradiography in the early postoperative period, and at six months postoperative. The maximum opening angle (MOA) was 67.919.8 degrees early postoperative and 63.0±8.5 degees at six months postoperative. No opening resistance was observed. The opening angle of the occluder was measured considering the blood flow direction in the aortic position. The left ventricular flow axis was determined from the left ventriculogram taken during the cardiac catheterization performed six months postoperative. The MOA was measured based on the assumption that the housing sits perpendicular to the ventricular flow axis. This opening angle of the occluder against the blood flow direction was measured in 26 patients, 66.2±9.1 (50-81) degrees. The stroke volume and the MOA was not related, but the stroke volume and the opening angle of the occluder against the blood flow direction was siginificantly related (r=0.51). In the conclusion, the OC valve in the position opens siginificantly in relation to blood flow. This fact supports the good clinical results of the OC valve.
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M. YAMADA, S. SEKIGUCHI, T. NARISAWA, Y. MATSUO, M. AIBA, N. MURATA, A ...
1996 Volume 25 Issue 3 Pages
607-609
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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From January 1990 to December 1993, a total of five patients were treated by limited operation for infections involving cardiac pacing system. We have done two different procedures for limited operation. (1) Procedure using implanted pacing lead. Generator and generator pocket were replaced, (2) Procedure using implanted pacing lead which was cut close to the subclavian vein and connected with new lead. Generator and generator pocket were replaced. Bacteremia, infection in the inside of lead insulation and infectious sign close to the subclavian vein are regarded as contraindication for limited operation. As there have been no recurrence of infection during follow- up periods with a range of 24 to 63 months, limited operation should be one of the choice for the treatment of infectious pacing system.
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T MASEKI, Y OHARA, T WATANABE, K YASUURA, M MURASE
1996 Volume 25 Issue 3 Pages
610-612
Published: June 15, 1996
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Eight SSIR pacemakers (PM), 13 DOD-PM and 11 SSI-PM were studied from 1980 to 1995 with special reference to battery longevity. The longevity of PM was defined to the period from implantation to explantation. PM longevity was compared among the mode and with the Japanese warranty period. The longevity of PM which were replaced according to the end of life (EOL) index was compared with the projected longevity of manufacturer. The output of PM explanted according to the EOL index was compared with the initial output. The longevity of SSI, SSIR and DOD was 9.9, 7.2 and 7.5 yrs. respectively. The longevity of SSI was significantly longer than that of SSIR and DDD. The longevity of SSI and DDD was significantly longer than the Japanese warranty period. The mean longevity of SSI and DDD replaced according to the EOL index was the same to the projected longevity. That showed the accuracy of EOL index. The output of DDD explanted according to the EOL index was significantly lower than the initial output. In conclusion PM can be replaced according to the EOL index and the Japanese warranty period may be reconsidered.
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Toshiyuki ISHIKAWA, Shinich SUMITA, Kazuo KIMURA, Naomitsu KUJI, Tsuto ...
1996 Volume 25 Issue 3 Pages
613-617
Published: June 15, 1996
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Efficacy of short atrioventricular (AV) delay and diastolic mitral regurgitation (MR) were studied in 20 patients (71.0±11.0 ‹SD› years old) with implanted DDD pacemakers. In 12 of the 20 patients, diastolic MR was not observed when the AV delay was set at both 115 and 215 msec. Cardiac output and pulmonary capillary wedge pressure (PCP) did not change. In 8 of the 20 patients, diastolic MR was not observed when the AV delay was set at 115 msec, and was observed at 215 msec. Cardiac output decreased from 3.9±0.6 to 3.6±0.6 1/min (p<0.05), and PCMP increased in 7 of the 8 patients (88%, p<0.05 vs. 17% in patients without diastolic MR at 215 msec of AV delay). Cardiac function may be improved by shortening AV delay when the diastolic MR was observed. On the other hand, short AV delay may be not effective for patients in whom diastolic MR was not observed.
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S SUZUKI, S FUKUNAGA, A EGASHIRA, I KOMESU, N ENOMOTO, A OHRYOJI, M KU ...
1996 Volume 25 Issue 3 Pages
618-621
Published: June 15, 1996
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Priming volume is only 260ml, and the effective gas exchange surface area is 1.7m
2. We clinically evaluatedit incomparison with SARNS 46310. Twenty-one patients who underwent elective acquiredvalvular heart surgery were divided into two groups: OPTIMA group (group-O; 11 patients) and SARNS 46310 group (group-S; 10patients). Blood gas analysis and hematological examinationwere carried out during cardiopulmonary bypass (CPB). Blood gas was maintained at high PO2 and acceptable PCO2 levels through CPB. There were no statistical differences between the two types of oxygenators in terms of plasma free hemoglobin, platelet preservation ratio, and complements (C3, C4, CH50, C3a).
The OPTIMA seems to be useful to reduce the amount of blood transfusions and to practice open heart surgerywithout blood transfusion.
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-ACCESS TO THE INTERNAL JUGULAR VEIN BY PUNCTURE-
M ONO, S SATO, J HIRAI, H KUROMITSU, S TODA, A SHOMA, K KITAURA, Y WAD ...
1996 Volume 25 Issue 3 Pages
622-625
Published: June 15, 1996
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We used retrograde cerebral perfusion (RCP) via the internal jugular vein (IJV) as an adjunct for the operation of aorta involving aortic arch. A blood access catheter was inserted in the IJV as the access for RCP. A balloon catheter was placed in the SVC and when RCP instituted the balloon was inflated to obstruct. Cardio pulmonary bypass (CPB) was usually accomplished (deep hypothermia) by the cannula on to the ascending aorta or femoral artery, and a long venous catheter through the femoral vein and positioned in the right atrium. The de-airing from the CPB line and ascending aorta was easily completed with both the normograde and retrograde perfusion, because of using the independent circuit.This simple circuit in the operative field makes operators can concentrate on the operation. The flow of RCP can not be restricted by the intemal jugular valves because the blood was perfused from the cranial site. The retrograde cerebral perfusion with this method through either a median stemotomy or a posterolateral approach was stably obtained. RCP via the IJV by puncture is useful and simple as an adjunct for preserving the brain during the operation of graft replacement of aorta involving aortic arch.
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H UNNO, T JIKUYA, Y SAKAKIBARA, N ATSUMI, Y TERADA, T MITSUI
1996 Volume 25 Issue 3 Pages
626-628
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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In six patients of total aortic arch replacement, we evaluated the cerebral oxygen dynamics under unilateral carotid perfusion by means of near infra-red spectrophotometry (NIRS). Alteration of total, oxygenated and deoxygenated homoglobin concentration in cerebral tissue were estimated by measuring the reflectance of rediated three different wavelengths of near infra-red light. Probes of NIRS were fixed on the left forehead of the patient. Cerebral low perfusion pattern (decresed oxygenated and increased deoxygenated hemoglobin) was observed in all patients. Three out of the six patients revealed progression of this change (group S) and others revealed balance of the change (group M). Mean perfusion rate was 6.7ml/kg/min in group S and 7.2ml/kg/min in group M. Mean rectal temperature of group S and M were 28.4 and 26.0°C and mean arterial blood temperature were 34.4 and 25.7°C respectively.
There was no statistical difference in these parameters but arterial blood temperature of group S was relatively higher than group M. According to these result, unilateral carotid perfusion under relatively high arterial blood temperature lead to progressive cerebral ischemia. NIRS is a simple, non-invasive and sensitive monitor of cerebral oxygen dynamics and we could present the suitable conditions of unilateral carotid perfusion by NIRS measurement.
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M AIBA, S SEKIGUCHI, Y MATSUO, T NARISAWA, K MORIYASU, N MURATA, A MUR ...
1996 Volume 25 Issue 3 Pages
629-631
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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To determine the effect of hemodialysis (HD) during cardiopulmonary bypass (CPB), we retrospectively reviewed six chronic hemodlalysis patients who underwent open heart surgery. Three patients were performed HD during CPB (HD group) and other three patients were not performed (N group). Blood urea nitrogen (BUN), serum creatinine (Cr) serum potassium (K) and hematocrit (Ht) just after operation were 33.1 vs 41.5mg/dl, 4.8 vs 6.2mg/dl 4.3 vs 3.9mEq/l, 24.6 vs 35.1% (HD vs N group, respectively). And those parameters had no significant difference in two groups. This study demonstrated that (1) HD during CPB had no significant decrease of BUN, Cr and K in chronic hemodialysis patients, (2) in elective operation, BUN, Cr, K and Ht should be corrected to the adequate levels before operation and extracorporeal ultrafiltration should be performed during CPB and continuous veno-venous hemofiltration with nafamostat mesilate performed after operation.
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T. YASUDA, A. FUNAKUBO, Y. FUKUI
1996 Volume 25 Issue 3 Pages
632-635
Published: June 15, 1996
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The effect of fluid mechanical stress on hemolysis. In this paper we describe an experimental study of the effect of fluid mechanical stress on hemolysis in artificial organs. In order to investigate the effect of an impact failure on red blood cells, in-vitro tests and flow visualization tests were performed by using extra corporeal circuit. The results are as follows: 1) The tracer collided against the inner surface of the visualization model under the condition of high flow rates. 2) The rate of hemolysis increased if the velocity of blood flow against the surface was more than 300cm/s. There suggest that the impact failure of red blood cells might be playing a major role in the hemolysis.
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T. NISHINAKA, N. NISHIDA, K. IHASHI, M. ENDO, H. KOYANAGI, S. SUZUKI, ...
1996 Volume 25 Issue 3 Pages
636-640
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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The Comparison of blood damage among centrifugal pumps and roller pump in open heart surgery. Today Centrifugal blood pumps have developed. To compare the blood damage among the centrifugal pumps and roller pump in open heart surgery, fifty four patients who underwent elective coronary artery bypass grafting were divided into five groups, the Nikkiso HPM15 group (Nikkiso) (Group N n=14), theBioPump, BP80 group (BioMedicus)(Group B n=10), the Capiox SP pump group (Terumo) (Group C n=10), the Lifestreamgroup (S. J. M)(Group L n=10), and the roller pump group (Tonokura)(Group R n=10). We measured hemolysis index, β thromboglobulin, and platelet count during cardiopulmonary bypass. When the parameters were analyzed with repeated measures ANOVA method, there were no significant differences among the groups in hemolysis index, β thromboglobulin, and platelet count. When the parameters were analyzed with one way factorial ANOVA method, the damage of the platelet in all of the centrifugal pumps were smaller than that in the roller pump group. In conclusion, there are no significant differences in blood damage among the centrifugal pumps and roller pump in open heart surgery. The centrifugal pumps have significant potential to be used for open heart surgery
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-Comparison of Bio PumpΔ BP-80, CAPIOXΔ CX-SP45, Nikkiso HPM-15 and roller pump in open heart surgery-
T. KOYAMA, T. YAMADA, K. KURITA, S. TAMAKI, S. HARA, H. SAKURAI, T. NI ...
1996 Volume 25 Issue 3 Pages
641-644
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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Blood trauma was estimated in 68 consecutive adult patients who underwent open heart surgery without blood transfusion during CPB so as to clarify possible differences among three centrifugal pumps (BP-80: 20 patients; HPM-15: 18 patients; SP45: 24 patients) and roller pump (R, 6 patients). Serum hemoglobin (S-Hb) and platelet counts (PLT) were measured before (just after induction of anesthesia) and during CPB. Each value was corrected by hemodilution, and the amount of increase of S-Hb (ΔS-Hb) and the degree of PLT change from the value before CPB (%PLT) were calculated and compared. Although ΔS-Hb gradually increased during CPB, the values of the four groups did not show any significant deference. The %PLT, on the other hand, decreased during CPB, but we could not find any significant difference among the four groups. We conclude from these findings that the centrifugal pump and the roller pump may cause blood trauma in the same degree during short-term CPB in adult patients.
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M ISHIYAMA, M AOKI, Y IMAI, Y TAKANASHI, S HOSHINO, K SEO, M TERADA, M ...
1996 Volume 25 Issue 3 Pages
645-648
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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We studied the biocompatibility of a heparin-coating by end-point attachment of an oxyg enator in infants undergoing open heart surgery for congenital defects. Biocompatibility was assessed by changes in platelet numbers, complement and bradykinin levels in 8 infants with the coated oxygenator and 8 with uncoated one. We found lower levels of bradykinin (p=0.03) and C3a generation (p=0.06) in coating group. There were no differences in platelet numbers nor complement levels of C5a between the two groups. These observations suggest that heparin coating improves biocompatibili ty and therefore may reduce the complications after cardiopulmonary bypass in infants.
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K. HATTORI
1996 Volume 25 Issue 3 Pages
649-654
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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We evaluated whether use of a cardiopulmonary bypass (CPB) circuit coated with heparin decreased coagulation and fibrinolysis. Thirty patients who were to undergo cardiac surgery were chosen and assigned to a group for which an uncoated or coated circuits were used. The activated clotting time was kept at 400 seconds or more during CPB. We measured the plasma concentrations of thrombin-antithrombinIll (TAT), fibrinopeptide A (FPA), antithrombin III (AT-III) α2 plasmin inhibitor-plasmin complex (PIC), and D-dimer (DD). Blood samples were collected first before the operation and 10 more times up to 24h after CPB ended. TAT and FPA levels increased in both groups, but during CPB, the increase tended to be smaller in both groups, and FPA did not increase in the group treated with use of the coated circuit. PIC and DD levels increased during CPB in both groups. With the coated circuit, the increase was significantly smaller than with the uncoated circuit during and after CPB. We concluded that the coated circuit reduced the activation of coagulation and fibrinolysis during and after CPB, and that use of the circuit is beneficial to patients undergoing cardiac surgery.
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-EXPERIENCE OF WEARABLE NOVACOR IN HENRI-MONDOR HOSPITAL
K. ISHII, K. YASUDA, Ph. DELEUZE, D. LOISANCE
1996 Volume 25 Issue 3 Pages
655-657
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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We describe six cases who had portable left ventricular assist systems “wearable Novacor” as a bridge to heart transplantation in Henri-Mondor Hospital, France between March 1993 to May 1995. The patients' mean age was 36 yeas and mean body weight was 67kg. Preoperative mean cardiac index was 1.4l/min/m
2 and mean pulmonary capillary wedge pressure was 25mmHg. Marked hemodynamic improvement was achieved immediately with the support of Novacor and they could walk around the ward within 8 to 20 days (mean 13 days). They could go out of hospital and one of them could stay at home bearing the system. All six cases were successfully transplanted and doing well. The duration of support ranged 52 to 169 days (mean 111 days). Complications were as follows; infectons: 4, late cardiac tamponade: 2, effusion in the pocket: 4. transient ischemic attack (aphasia). Wearable Novacor will provide a prolonged circulatory support and advantages regarding quality of life.
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M NAKAMURA, K KOKUBO, K SAKAI
1996 Volume 25 Issue 3 Pages
658-663
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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To improve the performance of dialysis membranes, it is important to relate diffusive and convective permeabilities with asymmetrical structure of the membranes. We evaluated the asymmetrical structure of three polysulfone dialysis membranes (PS-400, PS-UW, APS) by observation with SEM, comparison of sorption rates, BET method and DSC method. The membranes were found to consist of the skin layer near the inner surface and the supporting layer at interior region and the outer surface of the membranes by the observation with SEM. The sorption rate curves of inside to outside and outside to inside were different for PS-400 and PS-UW, and were the same for APS, suggesting that the differences in the sorption rate curve were attributed to the difference in the structure of the skin layer and the supporting layer. The pore size distributions of the membranes determined by BET method could not be evaluated for larger pore that almost comprise the supporting layer. The pore size distributions of the membranes determined by DSC method, representing those of the supporting layer, were similar. In conclusions, the polysulfone dialysis membranes consist of the skin layer and the supporting layer, and have the difference in structure of skin layer.
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T. SUNOHARA, K. KOKUBO, K. SAKAI
1996 Volume 25 Issue 3 Pages
664-669
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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Solute permeability reduction of dialysis membrane caused by protein adsorption is one of the factors to reduce its performance during clinical hemodialysis. Many highly permeable dialysis membranes recently developed have asymmetrical structure and may vary the performance and the performance reduction after protein adsorption depending on their asymmetrical structure. To determine the diffusive permiability for Thiourea, Tryptophan, Riboflavin, VitaminB
12, Cytochrome C of polysulfone dialysis membrane (PS-400, PS-UW, PS-NW, APS), dialysis experiments were made at 310K before and after bovine plasma protein adsorption using a single hollow fiber dialysis membrane at both ends of which optical fibers were inserted into the hollow. Dependence of ratio of intramembrane diffusion coefficient to diffusion coefficient in water, Dm/Dw on stokes radius and reduction of Dm/DW after the plasma protein adsorption were reflected with their asymmetrical structure. Dm/Dw for higher molecular weight solutes after the plasma protein adsorption reduced and that for lower molecular weight solutes slightly reduced. The ratio of membrane resistance to overall mass transfer resistance of higher permeable membranes (PS-UW, PS-NW, APS) was lower than that of conventional membrane (PS-400). Clearance reduction for larger solutes after the plasma protein adsorption attribute to the increase in membrane resistance and largeness of membrane resistance ratio to overall mass transfer resistance.
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T NISHIYAMA, R OHISHI, T OHDAN, H AMEMIYA, H OKUYAMA, T AKIZAWA, T IDE ...
1996 Volume 25 Issue 3 Pages
670-673
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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Efficiency and biocompatibility of hemodiafiltration (HDF) with polysulfone membrane dialyzer (Toray BS-1.3: BS) were compared with those with cellulose triacetate membrane dialyzer (Nipro FB-130U: FB) in 6 regular hemodialysis patients. No significant differences were observed between two dialyzers in the reduction rate of small molecular substances, however BS showed a greater reduction of β 2MG than FB. Removal of Myo, α 1MG and Alb in dialysate was greater by HDF with FB. Deterioration of SC and UFR during HDF due to high TMP remained within negligible range. Although HDF with FB increased C3a significantly, that with BS did not. From these results it is concluded that BS has high removal capacity for β 2MG and excellent biocompatibility not only for hemodialysis but also for HDF.
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N. NAKAMURA, N. KOIDE, H. SHIRAHA, K. UJIKE, T. SHINJI, H. HADA, T. TS ...
1996 Volume 25 Issue 3 Pages
674-677
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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A bioartificial liver support using primary culture hepatocytes as a bioreactor requires a large scale isolation of hepatocytes for a clinical practice. In this study we developed a quick method to isolate 100g hepatocytes in single cell from a 20-25kg pig. A pig under anesthesia was perfused from portal vein with heparinized saline followed by disperse-supplemented 0.05% collagenase. The liver was resected and re-perfused with 0.05% collagenase solution at 37°C for 10 minutes, resulting in isolation of a mixture of tissue fragments and some single cells. The tissue suspension was processed to a differential filtration using 4 layered metal filters with various mesh sizes ranging from 4.7 to 100 mesh. After larger tissue fragments were removed by smaller mesh-sized filters, most acinus-like tissue fragments retained on a 30-mesh filter. Thus, the 30-mesh filter was transferred to deep metal pan, received additional collagenase solution and incubated at 37°C under gentle agitation. This procedure allowed single cell to pass the 30-mesh filter gradually. The filter-passed cell suspension was further differentially filtrated with larger mesh-sized filters in the presence of collagenase solution. The filtrate after 100 mesh filter was collect, immediately cooled, and washed thrice by low speed centrifugation. Over 90% cells in the final cell preparation were in single cell and viable. By the combination of liver perfusion and differential filtration, about 100g hepatocytes in single cell were prepared from a 20-25kg pig within 2 hours after the initiation of in vivo liver-perfusion.
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-OPTIMIZATION OF OPERATION CONDITIONS OF THE ARTIFICIAL LIVER-
S. WADA, H. IJIMA, T. MATSUSHITA, K. FUNATSU
1996 Volume 25 Issue 3 Pages
678-682
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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It was found from
in vitro experiments that optimum superficial velocity in multi-capillary (MC) PUF packed-bed was about 65.1cm/min, which improved the performance of the artificial liver without reducing the immobilizing ratio of hepatocyte/spheroid in MC-PUF packed-bed.
By the optimization of medium (or plasma) flow rate and scaling up of MC-PUF/spheroid packed-bed, it was achieved that the decrease of ammonia concentration and repression of increase of bilirubin concentration and of artificial liver module side circulation line in extracorporeal circulation with severe hepatic failure rats.
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Determination of antibody concentration and electrochemiluminescence mechanism
H HARAMOTO, Y YOSHIMI, K SAKAI
1996 Volume 25 Issue 3 Pages
683-687
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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We designed a technique of continuous and simple immunoassay using an electrochemiluminescence flow cell for monitoring antibody or antigen concentration as an indication of optimal amount of immunosupressors, and attempted to clarify enhanced ECL intensity produced by the binding of antigen and antibody. Luminol-labeled antigens were used to measure the concentration of these antibodies. Luminol-labeled anti-human serum albumin (HSA) antibody was used to measure HSA concentration. Both anti-HSA antibody and anti-immunogloblin G antibody ranging from 0 to 2.2mg/ml, 0 to 200μg/ml, respectively, increased the ECL intensity of aqueous luminol-labeled antigens. HSA ranging from 0 to 3.8μM also increased the ECL of luminol-labeled anti-HSA antibody. The ECL intensity of luminol-labeled antigen also increased with antibody concentration in bovine plasma. These results demonstrate that this system is promising for the homogeneous immunoassay of antibodies or antigens and the principal reason of ECL intensity enhancement is an increase in quantum yield of luminol caused by the binding of antigen and antibody.
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A KAWAMURA, M YONEKAWA, M TAKAHASHI, K KUKITA, J MEGURO, T TAMAKI, M O ...
1996 Volume 25 Issue 3 Pages
688-691
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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Cryofiltration (CRYO) is the system of protein adsorption using heparin. Under low temperature and adding of heparin, cryogel is produced from the plasma of patients by on-line system. The produced cryogel, however, narrow and obstruct pores of the filter. Therefore, the second filter has to be irrigated to remove the produced cryogel regularly. And device of this washing method is very important because it decides the size and volume of the removing pathological proteins. In this study, we devised two types of washing method. One was A type: 300mmHg of perfusion pressure, 200ml of replacement saline and 300ml of washing saline. B type was 400mmHg of pressure, no replacement and 50ml of washing saline. Reduction rate of pathologic proteins and physiologic influence of patients by washing methods were observed. EDA (+) Fibronectin (one of pathological protein) was reduced to 70.2±2.3% by A type and 81.6±2.0% by B type after CRYO. 340ml of body fluid was increased by A type and 490ml was reduced by B type. As a result, 100% of efficiency of A type was corresponded to 70% of B type. This 30% of a deduction will be cut the perfusion time. And physiologically, B type was better than A type.
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M. YONEKAWA, A. KAWAMURA, E. SAKASHITA
1996 Volume 25 Issue 3 Pages
692-696
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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One of the important aim of treatment for rheumatoid arthritis (RA) by apheresis is to attenuate joints pain. Our previous studies elucidated that EDA (+) fibronectin (EDA (+) FN) level in RA patients plasma was higher than that of other patients, it had respect to joints pain, and it might be a good indicator of joint pain. Our strategy is that EDA (+) FN is drawn out from tissues to blood by heparin injection, and then a new adsorbent removes selectively EDA (+) FN from plasma. We developed a new adsorbent of EDA (+) FN, a heparinized cellulose (OHC-10). In in vitro study, the reduction rate of EDA (+) FN and total FN was 69% and 14%, respectively. The reduction rate of total protein, albumin, IgG, IgA, IgM, and fibrinogen was less than 5%. OHC-10 could remove selectively the EDA (+) FN. The reduction rate of EDA (+) FN did not depend on temperature and its concentration. On the other hand, the reduction rate of AT III was high as well as EDA (+) FN, that was consequent on the high affinity of AT III with heparin. However in in vivo study using dogs, hemostasis just after removal of intravenous catheter was not difficult, and after 24 hours AT III level recovered to almost same level as that of pre-experiment. These data confirm that OHC-10 will be able to remove selectively and efficiently EDA (+) FN, and must be a beneficial device.
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T. OKADA, T. NAKAO
1996 Volume 25 Issue 3 Pages
697-701
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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The kinetics of lipids in the rebound phase after Low-density lipoprotein apheresis (LDL-A) was evaluated in 8 patients with Familial hypercholeste rolemia (FH) or other diseases. One-compartment model was adapted to the cholesterol kinetics, and the time average conce ntration (TAC) of total chole sterol (TC) in the rebound phase was calculated in each case. We also tried to determine the optimal treat ment interval to achieve the desirable TAC. In more than half of cases, serum LDL level returned to pretreatment level after 7 days. The TAC level of TC of 14 days after single treatment was about 15% lower than pretreatment TC level. In FH patients, treatment at intervals of 7-14 days is needed to suppress TAC of TC below 240mg/dl. It is necessary to observe the rebound phase of lipids after LDL-A in each patient, and adaptation of kinetic model such as one-compartment model would help in order to estimate the reduction effect of lipids by LDL-A.
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I. KAETSU, K. UCHIDA, S. UETA, K. TANABE, K. SUTANI, A. DOI, M. KAWABA ...
1996 Volume 25 Issue 3 Pages
702-706
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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Construction of novel drug release system with silicon chip was investigated. The silicon wafer was fabricated with lithography-etching to have a pitch and holes for drug charge and reservation. The chip was covered with a glass having holes for the drug release. The holes were coated with crosslinked polyacrylic acid membrane as a molecular sensor and gate. It was found that the release of model drug (methylene blue) was promoted with the increases of pitch breadth, chip numbers, and hole numbers in cover glass. The drug release occurred in responsive to pH changes in the medium. The release was promoted under acidic condition and retarded under alkaline condition by the work of molecular sensor and gate.
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K. ABE, K. SUZUKI, T. OKANO, Y. SAKURAI, T. HORIE
1996 Volume 25 Issue 3 Pages
707-713
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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A difference of the inhibitory ability of ultrastructural changes of platelets adhered to PHEMA-PSt-PHEMA ABA type block copolymer (HSB) and Biomer surfaces was evaluated quantitatively by a high-speed image processor-analyzer (IA). That is to say, after inputting transmission electron microscopic images of ultra-thin vertical sections of the adhered platelets in the IA, the platelet images were measured about 5 parameters (area, breadth, roundness, irregularity and number of storage granules (SG) per 1μm
2), and significant-difference tests were carried out statistically with these data. The area, breadth and roundness at the HSB vs. the Biomer surfaces didn't indicate any significant difference. However, the irregularity and number of SG per 1μm
2 indicated some significant difference (P<0.05). It was found that the inhibitory ability of the ultrastructural changes of the platelets adhered to the HSB surfaces was superior compared to that of the Biomer surfaces. It was suggested that the HSB surfaces inhibited remarkably the cytoskeletal rearrangement of the adhered platelets compared to that of the Biomer surfaces. [Abbreviations: PHEMA, Poly (2-hydroxyethyl methacrylate); PSt, Polystyrene]
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K FURUKAWA, T USHIDA, T TATEISHI
1996 Volume 25 Issue 3 Pages
714-719
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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In this study, we investigated whether the 3 types of cells constituting vessels can rearrange spontaneously themselves in the hierarchical structures like the nature vessels in vitro. When endothelial cells (EC), smooth muscle cells lined (SMC) and normal fibroblasts (FB) were cultured separately within collagen gels, we observed that just after the inoculation EC aggregated in the gels to form sprout. It was confirmed that EC formed cobblestone-like monolayer on the surface of the gels by sprouting about 6 days after casting the mixture, while smooth muscle cells and fibroblasts proliferated randomly without sprout and cell-cell network in the collagen gels. Therefore, we investigated whether EC could make monolayer on the surface of the gel or not when three types of the cells constituted of vessels, EC, SMC and FB, were co-cultured. As the result, it was confirmed that the many endothelial cells were observed on the surface in short term culture. However, after 3 weeks, only few EC could be observed on the gels. It seemed that EC adhered more weakly to collagen gel surface than SMC and FB.
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T. KAWASHIMA, O. KAMISAWA, N. HASEGAWA, Y. MISAWA, T. HASEGAWA, K. FUS ...
1996 Volume 25 Issue 3 Pages
720-722
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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Gelatin-sealed knitted Dacron grafts (Bifurcated Gelsoft®) were electively implanted into the abdominal aorta in 44 patients. Postoperative inflammatory responses and changes of endotoxin (both Toxicolor and Endospecy) were evaluated. Eleven patients had fever above 37.5°C after the 7th-postoperative day (POD). Only one case revealed that the fever came from the prosthesis. Patients were devided into 2 groups, feverish patients (g-F, n=11) and normal temperature patients (g-N, n=33) after 7POD. Postoperative body temperature were significantly higher in g-F, and on 14POD it went back to normal in both groups. The values of WBC in g-F were slightly higher than in g-N, and they became normal after 7POD. The levels of CRP showed no difference, but it was still high on 7 and 14POD. In terms of endotoxin, Toxicolor demonstrated high on 1POD and went down to normal after 7POD, but Endecy kept within normal range. In conclusion, a Toxicolor-reactive substance elevates with implantation of a Gelsoft®, and the substance is not endotoxin. It would not be appropriate that endotoxin is an origin of fever between 7 and 14POD.
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Y. INOUE, R. YOZU, T. UEDA, A. MITSUMARU, Y. SANO, S. KAWADA
1996 Volume 25 Issue 3 Pages
723-727
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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To determine the feasibility of transluminal closure of Atrial Septal Defect (ASD) using a staple-catheter device with a guiding catheter in an experimental setting of a beating porcine heart. [METHOD] In 6 porcines under thoracotomy and general anesthesia, intact atrial septum (IAS) was viewed by transluminal cardioscopy, and stapling was attempted at the IAS with a stapler inserted through the trocar guiding catheter via the right atrium under thoracotomy. Then an artificial IAS defect was created with forceps inserted through the guiding catheter, and staploplasty correction for the artificial atrial septal defect was attempted. [RESULTS] The level of injury occuring during percutanous staploplasty was low and the safe anchoring of the staple device was successfully done in 4 subjects. These can be monitored/documented by cardioscope, intercardiac echo device, and post mortem macro-histological examination. [CONCLUSION] Although the size and flexibility of the stapler and the guiding catheter need improvement, our results demonstrate the strong potential for transluminal closure of atrial septal defect using this novel staploplasty technique which could eliminate current necessity of open heart surgery.
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N KEIRA, S KATOH, M TSUKAMOTO, T YAMAMOTO, M SATODA, H TATSUKAWA, S NA ...
1996 Volume 25 Issue 3 Pages
728-732
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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The intravenous reinfusion of autogenous ascitic fluid after filtration and concentration has been reported to be useful. However, the requirement for an expensive double filtration monitor and its supervision have made it difficult to utilize this procedure. A new 2-pump-machinery-based system that was developed from the prototype 3-pump-machinery-based system achieved a higher protein recovery ratio, but the treatment time was doubled. Subsequently, a non-machinery-based system for the infusion of ascitic fluid was developed and its usefullness was assessed. In fundamental studies utilizing bovine plasma, this procedure was found to be covenient, rapid and effective. Bovine plasma with a protein concentration below 3.0g/dl could be treated using this system. Samples containing blood (hematocrit: 0.5%) could also be treated, but the time required was doubled that for plasma with the same protein concentration. The protein recovery ratio was about 90% with the 2-pump-machinery-based system and the non-machinery-based system based on gravity-dependent flow. We conducted 62 treatment sessions (31 with each system) in 19 patients with ascites refractory to various drugs including diuretics. Assessment of the differences between the two systems indicated that the non-machinery-based one was superior with regard to the protein recovery ratio and treatment time.
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Kazuyuki ISHIBASHI, Kouhei KAWAZOE, Takehisa MATSUDA
1996 Volume 25 Issue 3 Pages
733-737
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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We developed hybrid grafts hierarchically incorporated with endothelial cells (ECs), smooth muscle cells (SMCs) and fibroblasts (FCs), and investigated the cellular behaviors and ultrastructure of regenerated extracellular matrix (ECM) of those grafts
in vivo. Hybrid vascular grafts were constructed on knitted Dacron grafts (ID=4mm, Length; 6cm)
in vitro. Hybrid grafts were hierarchically structured with a confluent monolayer of ECs, a middle layer of SMCs and an outer layer of FCs. The designed artificial ECM was a mixed gel of type-I collagen and dermatan sulfate. Hybrid grafts were implanted in canine carotid arteries of 17 dogs for up to 23 weeks without anticoagulant. Patent grafts (n=15 out of 17 implanted grafts) were completely endothelialized, Observation of grafts at 12 weeks showed that hybrid grafts should be achieved similar to those of natural arteries structured at both cellular and biomolecular levels in many parts. At 23 weeks, hierarchically structured hybrid grafts completely resembled natural vessels without anastomotic hyperplasia. Thus, it can be said that hybrid grafts incorporating intima-, media- and adventitia-type cell layers can significantly enhance the process of arterial wall reconstruction.
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Y. MITAMURA
1996 Volume 25 Issue 3 Pages
738-743
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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An actuator is one of the obstacles to delay the development of totally implantable artificial hearts. Many novel artificial hearts have been developed in Japan to overcome the obstacles. We have developed a ballscrew-driven intra-abdominal assist pump that ejects a flow of 6L/min with an efficiency of 21%. The followings are required to develop implantable artificial hearts; high-power, highly efficient, small actuator; blood compatible blood pump; endurable system; in vivo energy technology; and national R&D project and collaboration with industries.
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T. YAMBE, S. NITTA, S. NAGANUMA, T. SONOBE, Y. KAKINUMA, H. AKIHO, S. ...
1996 Volume 25 Issue 3 Pages
744-748
Published: June 15, 1996
Released on J-STAGE: October 07, 2011
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In order to analyze the autonomic nervous system during left ventricular assistance using oscillated blood flow with Vibrating Flow Pump (VFP), fluctuations of the hemodynamic parameters were evaluated by the fast fourier trasnform with beat-to-beat basis. Chronic animal experiments of the left heart bypass with VFP using four healthy adult goats were performed. Specral analysis of the hemodynamic parameters were performed for the evaluation of the autonomic nervous system. Our results suggest that Mayer wave fluctuations of the hemodynamics were significantly decreased during left heart bypass with VFP, suggesting that sympathetic tone were decreased during left heart bypass with oscillated blood flow.
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