In order to collect large amount of albumin, SACS applying the DFPP principle was newly introduced in this paper. Characteristics of SACS were examined in in vitro experiments. In SACS, two types of membrane filters, a plasma fractionator and a hemofilter, were used. Albumin was penetrated in the first membrane but not the second. At 60min after a start of the experiment, more than 15g of albumin and less 1.5g of IgG were collected in 240ml of plasma. There is a limit of separation characteristics between albumin and IgG.

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Their symptoms have been given to anti-cardiolipin antibodies (Anti-CL).
In this study, we tried to remove anti CL for improvement of their symptons. We developed the absorvent that is made of dextran sulfate (DS). DS has come to be used in absorption of low density bipoprotein.
We performed plasmaphevesis on 2 SLE patients using a DS column. This DS column is useful for treating SLE patients.

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After somatic cell fusions between murine spleen cells immunized with several organic anion-protein conjugates and murine myeloma cells, we have prepared many kinds of monoclonal antibodies against haptenic low molecular organic anions. Low molecular organic anions such as metabolic waste, drugs, and toxins usually tightly bind to serum proteins. They therefore cannot easily be removed from blood with various adsorptive resins or hemodialysis. Thus, using these monoclonal antibodies which possesed high affinity enough to compete with serum proteins for the organic anions, we designed a new approach to remove organic anions from blood selectively. As an example, among the monoclonal antibodies raised against bilirubin, we selected one clone which had high affinity enough to compete with serum albumin for bilirubin binding. The monoclonal antibody immobilized on agarose beads showed higher affinity to bilirubin than albumin did, and effectively removed bilirubin in jaundiced human sera in vitro.

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For specific removal of pathogenic anti-acetylcholine receptor antibodies in Myasthenia Gravis we made adsorbents carrying a chemically synthesized peptide corresponding to a part of acetylcholine receptor. A synthetic peptide corresponding to a residue 183-200 of Torpedo californica acetylcholine receptor α-subunit bound α-bungarotoxin one of antagonists of acetylcholine receptor. An adsorbent carrying this synthetic peptide also bound α-bungarotoxin, and preserved this binding activity after steam-sterilization. From the results of many safety tests, this adsorbent proved to have high safety.

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Based on the availability of amino acid sequence of Torpedo acetylcholine receptor, the segment α 183-200 was synthesized and used for an antigen-specific therapy in myasthenia gravis. This synthetic peptide was confirmed to be immunogenic in the induction of the animal model of immunopharmacological blokade and also antigenic in the detection of antibody in human myasthenic sera. Two patients, who had high titers of anti-peptide antibody, were treated with the plasmaperfusion by use of the peptide-bound adsorbent on 2 consecutive days. This treatment specaficically reduced the corresponding anti-peptide antibody, and also provided an improvement for myasthhnic state as estimated by electrophysioloic parameters of neuromusular transmission.

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In order to level up targetable therapy, it is essential to increase the material functions, such as recognition (sensor), processing (processor) and responsive release.
Especially materials which can recognize a specific biomolecule or a specific cells among lots of species should be very important in the design of targetable artificial organs as well as missile drugs. In this report, we summarize the experimental results in which specific polymers to B-lymphocyte and liver parenchymal cells were successfully designed.

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Relevance of anti-α-fetoprotein antibody for targetting chemotherapy-Using AFP-secreting AH66 rat hepatoma cells and APP-bound acrylic beads (APP-B), artificial cells expressing surface antigen, the effect of blood APP level on the accumulation of radiolabeled rabbit anti-AFP antibody in the site of tumor and beads implanted in rats was examined. Scintigrams of hepatoma-bearing rats with implanted APP-B showed a marked localization in AFP-B site, but not in the tumor site on day 5 after the injection of radiolabeled antibody. The imaging of AFP-B was most satisfactory in normal rats with extremely low blood APP. Tissue/blood radioactivity ratio in AFP-B on day5 was found to be significantly higher in normal rats (17.43±5.55), compared with 6.66±1.67 in the tumor-bearing rats (p<0.01), while the ratio of APP-B in tumor-bearing rats remarkably recovered to 11.20±0.25 (p<0.01) after whole blood exchange to reduce an elevated serum APP level. The accumulation of anti-APP antibody in the tumor was not observed irrespective of APP-B. Microautoradiography of tissue sections showed the specific localization of radioactivity on the surface of APP-B but not on the surface or the inside of the tumor cells. Immune complexes were detected in plasma of tumor-bearing rats 1min to 7 days after the administration of the radiolabeled antibody. In conclusion, the application of anti-APP antibody for the immunodiagnosis and targetting chemotherapy of tumors is limited to the case of the expression of APP on the surface of tumor cells and lower APP level in circulation.

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Seven different types of oncolytic drugs were modified according to our own technique. They were Adriamycin (ADM), 5-FU, Mitomycin C, Methotrexate, Bleomycin, Peplomycin and cis-platinum. Each was entrapped into an insoluble fibrin clot which was enhanced with our newly devised material, “G·T·XIII” and fibrinogen. In this paper, an ADM-material was mainly studied. The oncolytic effects with the material were remarkable, in in vivo studies. The material together with fibrinogen was applied to patients with malignant pleural effusion in serious condition and the clinical results were satisfactory. Such was called “Bio-Adhesio-Chemo (BAC)” therapy. The antineoplastic mechanism with the material was also discussed in this paper.

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The microwave (MW) in 430MHz band was adopted as a physical action, compared with ultrasound. Polyelectrolytes which showed large values of the relative loss factor (ε") were easy to generate heat by 433MHz MW irradiation. When a strong polyelectrolyte (PE) was injected into the phantom simulated to muscle tissue in value of ε", it was confirmed that the PE was more heated than the phantom by external MW irradiation. The action of 433MHz MW is considered to be the heat evolution due to ionic conduction and relaxation losses. A localized drug-administration induced by selective microwave irradiation, that is, a physical targeting can be expected if the macromolecular prodrug in polyelectrolyte system is utilized.

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Random copolymers of N-isopropyl acylamide (IPAAm) and butyl methacrylate (BMA) (5mole%) have been syntehsizedo. The complate on-off permeation control of the macromolecule, insulin and glucose are found between 30°C and 20°C. The shrunken surface of the hydrogel at 30°C immediately blocks the permeation of insulin and glucose. By lowering the temperature to 20°C, the shrunken surface queickly recovers its equilibrium swelling and allows permeability of both species. Also, a pulsatile release pattern of indomethacyn was found to be regulated by temperature changes between 20°C and 30°C due to the reversible swelling properties of poly (IPAAm-co-BMA). These data represent the first experimental results showing on-off switching phenomena of thermosensitive hydrogelso.

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A new multidisciplinary treatment has been performed for unresectable advanced cancer patients since 1984, in which percutaneous intra-arterial infusion of anticancer agents to the tumor-bearing organ via an implantable vascular access device (VAD) and rapid removal of anticancer agents in the general circulation by hemoperfusion over charcoal are undertaken. Reported herein are clinical usefullness of the VAD implanted in 62 patients and clinical effectiveness of the combination therapy. In 60 patients have been treated by the tar getting chemotherapy with VAD, it is possible to administer anticancer agents percutaneously and repeatedly during 6.2 months in the average (range 0-24 months) and 87.4% of the VAD are functioning over 6 months without obstruction of a catheter. Only three devices were removed because of peridevice infection. This result shows that the VAD is a useful device in order to perform the targetting cancer chemotherapy. In 12 of 20 patients combined with charcoal hemoperfusion, a remarkable reduction in tumor size of more than 50% was observed without lethal myelosuppression. The efficacy rate (60%) was significant statistically (p<0.001) compared with other treatments in this study.

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We have already reported that collagen-coated ultrafine polyester mesh (CUFP-1) was superior to glutaraldehyde-treated equine pericardium with regard to ease in suturing, antithrombogenicity, and healing quality in an animal experiment. Although CUFP-1 with air-dried collagen was a good cardiac wall substitute, CUFP-2 with freeze-dried collagen was developed as a further refinement. Both materials were sutured as patches in the right ventricular outflow tract and were evaluated. They were both excellent in handling during operation. Observation of the resected specimens revealed almost no thrombus formation on the inner surface of either material. Light-microscopic observation showed that neointimal formation and reconstruction of the material wall were promoted more in CUFP-2 than in CUFP-1. The collagen of CUFP-2, which has a sponge-like construction with many tiny holes, provided a better environment for cell migration and proliferation. Although CUFP-1 was disinfected and stored in 70% ethanol, CUFP-2 could be sterilized with ethylene oxide and stored more easily than CUFP-1.

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The study was conducted to understand the mechanism of adhesion and growth of ECs on collagen for a logical design of an artificial basement membrane. The ECs adhesion and spreading was significantly inhibited as ECs were preincubated with synthetic minimal amino acid sequence of adhesive site of adhesive proteins such as fibronectin and collagen. On the other hand, the adhered ECs were delaminated by the addition of RGDS in really stage of culturing. These strongly indicate that the RGDS receptorligand mechanism is primarily dominated in adhesion and spreading processes of cultured ECs.

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In order to evaluate the biocompatibility, a technique of cell culture on a membrane surface was introduced. Cell proliferation was evaluated by counting cells after tripsin treatment every 24 hours after an initiation of the cultivation. Cell growth curves of various membrane materials were plotted as a number of cells in dishes versus an elapsing time. Curves were categorized into four types. The bioassay technique described is expected to be applicable for biocompatibility evaluation of membranes potentially usable for artificial organs.

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The influence of contact with biomedical materials on neutrophils was studied through the measurement of chemiluminescence due to produced reactive oxygen. Membranes of PMMA, cellulose and PEO were used as biomedical materials, as they were or after treatment with plasma proteins. Reactive oxygen extracellularly released on contact with membranes was measured with luminol solution, while reactive oxygen released into phagosomes was measured with luminol-bound microspheres. The amount of released reactive oxygen remarkably varied with the kind of material and treatment with plasma proteins. In this experiment, the amounts of reactive oxygen measured with luminol solution and luminol-bound microspheres increased or decreased in the opposite way to each other.

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As there are not so many informations of non-specific activation by synthetic polymer, we tried to clarify the nature of non-specific activation. Platelet responces to cationic polymers, e. g. adhesion and release of nucleotides, were not effected by RODS ligand. It was thought that RODS receptors don't operate in the interaction with cationic polymer. The depression of platelet adhesion was observed markedly when the sialic acids on the surface of platelet were removed more than 50%. This suggests that several sialic acids cooperately play a role of adhesion site of platelet to cationic polymer. According to these results, it was suggested that the interaction between platelet and cationic polymer was based on rather sialic acid than RGDS receptor.

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Reconstituted collagen films were cross-linked using a new method. The method can be a useful tool for controlling biodegradation and stability of collagenous materials. The films were treated with Ribose, and irreversible covalent bonding of rebose-derived structures to protein occurred. This reaction has similarities with aging of long-lived protein in vivo. The treated films got a brown color and swelling degree was reduced. The tensile strength was increased but elasticity still remained.

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Simple polyethylene films and collagen-polyethylene composite films were implanted into rats subcutaneously and the respective rates of tumorigenesis were compared. After 24 months of observation, the tumorigenesis rate for collagen-polyethylene composite (14/80, 17.5%) was significantly lower than that for simple polyethylene (31/80, 38.8%). From these results, collagen-plastic composite materials seem to be effective for controlling foreign body reaction and for suppressing tumorigenesis reaction.

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CO₃ apatites with chemical compositions and crystallographic properties similar to those of bone was mixed with 0.5wt% collagen solution. The composites 4hr-UV-irradiated and incubated in 0.9% NaCl solution at 37°C were less deformed than non-UV-irradiated samples, under a compressive force. The biocompatibility of the composites with surrounding tissues seemed to be good, under the periosteum cranii of rats and rabbits. The composites treated with fibrin glue in addition to the UV-irradiation kept their shape even after 1-month-implantation. The newly synthesized bone-like substance was observed on the bone facing to the composite.

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The newly developed Aluminium-gel is represented by a chemical formula AlO(OH)·H2O (0≤n<1) and was recognized to have a unique ability to adsorb phosphorus by a physical process while a Amorphous AHG, Al(OH)3, adsorbs phosphorus through a chemical reaction. Although Al-gel adsorbs phosphorus by a mechanism entirely different from that involved in the phosphorus adsorption by AHG or precipitated calcium carbonate, this study demonstrated that Al-gel has an exceptional ability to adsorb phosphorus at low dosages. Based on the properties of Al-gel reported here, Al-gel is expected to be extremely useful clinically as a preventive drug for hyperphosphatemia in patients as a substitute for AHG or precipitated calcium carbonate which very likely introduces free Aluminium ions and calcium ions into the body.

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Compatibility with skin tissue of three kinds of typical bioceramics was evaluated. Sintered hydroxyapatite, β-tricalciumphosphate and glassy carbon formed in button-shape were percutaneonsly implanted through the dorsal skin of mongrel dogs and were examined histologically at 2, 4, 12 and 32 weeks after implantation. Hydroxyapatite and β-tricalciumphosphate were in close contact with skin tissue. Neither serious inflammation nor infection were observed. On the other hand, serious infection was frequently observed with glassy carbon. It was suggested that hydroxyapatite and β-tricalciumphosphate have good compatibility with skin tissue compared with glassy carbon and is suitable for a long-term percutaneous device.

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Biodegradable antiadhesive membrane with heparin slow release was newly developed. It showed a perfect antiadhesive property on the large intestine surface in an animal study. Four months after the implantation, the membrane was already absorbed and the wound surface was covered with mesothelial cells. Human amnion was cross-linked with a polyepoxy compound after the impregnation of protamine sulfate into its collagen matrix, and was heparinized ionically in heparin solution. The deposition of fibrin on a wound surface leads to the formation of cellulo-fibrous adhesion tissue. Heparin which inhibits the precipitation of fibrin is effective in preventing the adhesion. As an antiadhesive membrane for soft tissue, antiadhesive property and no interference on wound healing after the prevention of the adhesion were required.

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Five different materials, equine pericardium, bovine pericardium, porcine pericardium, silicon rubber and expanded polytetraf luoroethylene (EPTFE) surgical membrane, were evaluated experimentally to find a suitable pericardial substitute to prevent pericardial adhesions. Xenopericardiums were found to have higher levels of adhesion and epicardial reaction. Signs of organization were found in these materials histologically. It was suggested that xenopericardiums were not suitable for prevention of pericardial adhesions. The silicon rubber had significantly lower levels of adhesion compared with the equine pericardium, the porcine pericardium and the EPTFE membrane. However this material had the most significant epicardial reaction. So it was considered that silicon rubber was not acceptable in such cases as aortocoronary bypass resurgery. The EPTFE surgical membrane had no superiority for adhesion or epicardial reaction, but it seemed to be useful because no sign of organization was found in this material histologically.

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New type of bioabsorbable pledget was made from non woven fabric of PGA fibers. After evaluation in the in vivo implantation test using dogs, they were studied on the clinical evaluation at the pulmonary operations in our four hospitals.
The total number of the case were 50; 11 cases for the tracheobronchial systems and 39 cases for pulmonary fistulas or defects of pleura. Compared with the conventional non absorbable pledgets these PGA pledgets showed satisfactory results. Especially for the cases of pulmonary cystic diseases, the application of the PGA pledgets made the post operative air leakage duration shorten. In 50 cases neither side effect nor complication was observed. Conclusively, the PGA pledget can be useful and valuable as a new absorbable operative devices.

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Thrombin (T) and factor XIII (XIII) were immobilized on gelatin material (G) by freeze drying method to provide a biodegradable material for wound healing. We studied the effects of the material on acetic acid ulcers in rats. After ulcers were induced, G·T·XIII was injected in the ulcers (treated group). The controls were not given any treatment. All ulcers in the former group, disappeared within the observation period and were competely filled with granulation tissues. In the control group, 5 rats died of perforation of the ulcers and in the surviving rats, repair of the lesion was remarkably poor. We conclude that topical injection of G·T·XIII is one of effective treatments for gastric ulcer.

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We have developed a bypass-catheter of the portal vein from heparinized hydrophilic polymer (Toray, Anthron®). Using the catheter-bypass between the mesenteric and femoral veins to prevent intestinal conjestion caused by acute portal vein obstruction during operations, the resection of the portal vein could be done with safety and ease in hepatobiliary and pancreatic cancer surgery. However, in the case of extended operations such as simultaneous resection of the portal vein and hepatic artery, hepatic ischemia will become a serious problem and it will cause hepatic failure after the operation. So, we have developed a new hypass-catheter with a ballon on one end to prevent slipping off from the portal vein. Using the catheterbypass between mesenteric and intrahepatic portal veins through the hepatic hilum hepatic ischemia can be prevented. The safety and efficasy of this new bypass method has been proved by the animal experiments and clinical applications.

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This study was conducted to evaluate the relative hemoconpatibility of various segmented polyurethanes (SPUs) under development and being commercialized and to compare the in vitro results with in vivo results. The results of in vitro test showed: 1) the contact activation of coagulation system, the complement activation and whole blood coagulation are enhanced with the an increase in nitrogen content of the outermost surfaces. 2) The cell adhesion as a measure of platelet adhesion showed that no cell adhesion was observed for hydrophilc SPUs. This was in a marked contrast with hydrophobic SPUs. The most antithrombogenic SPU is found for the SPU best-performed in vivo.

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The changes in properties of segmented polyurethane (SPU) after long term implantation were investigated. SPU films retrieved after 3-26 months of implantation were examined by GPC, ATR-IR and tensile test. The significant decrease in molecular weight of SPU implanted for 20 months was observed. Cleavage of the urethane linkage in the implanted SPU was suggested from ATR-IR spectra by the facts that urethane absorption decreased and that amines were formed. The tensile strength was reduced 32% at 3 months, but almost constant after that time. Statistically significant change in elongation at failure was not observed even after 26 months. Though cleavage of polymer chain of the implanted SPU was suggested, its effect on tensile strength or elongation was not observed.

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Commonly, calcification process accompanies with pseudeneointima (PNI), thrombus adherent and defects of polyurethane such as cracks and microbubles caused by stress concentration. These calcification mechanism related with dead cells, called dystrophic calcification. However, we found in vitro calcification process without cells, thrombus and stress concentration. Gelatin coated sponge polyurehtane was prepared and immersed in bovine serum. After weeks, evidence of calcified deposition was formed in the samples of gelatin coated polyurethane, PMMA and silicone elastmer, which were identified by means of Energy Dispersion Analysis of X-ray (EDAX). Also, gelatin coating and treatment of glutaraldehyde enhanced calcification process.

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An analytical method of 4, 4'-diaminodiphenylmethane (MDA, methylenedianiline, a carcinogen) in thermoplastic polyurethane film (PU) was developed. Generating of MDA in PU by sterilization with gamma-ray and autoclaving and leaching of MDA from PU to methanol and to serum were studied. Two kinds of PU shown as follows were used for the experiments: PU-1-3, polymer between 4, 4'-diphenylmethanediisocyanate (MDI) and poly (tetramethyleneglycol) (PTMG); PU-4-6 MDI/PTMG prepolymer was chain-extended with 1, 4-butanediol. No MDA was found in both of PU-1-3 and PU-4-6 when sterilized with gamma-ray below 10 Mrad and in PU-4-6 when autoclaved at 121°C for 30 min., whereas a significant amount of MDA generated in PU-1-3 when autoclaved. Amount of MDA leached to serum from PU-1-3 was similar to that leached to methanol.

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This study was conducted to develop photocurable resins for medical applications. The designed resins are based on diacrylates with hydrophilic spacer (mol. wt. of spacer; 4, 000). The photocurable system impregnated with photoinitiator and sensitizer completes to cure under irradiation of visible light within a few minutes in moisture. The resultant polymers are gel-like, moistureadsorbable and elastomeric. The incorponation of proteins and cells in gels are easily achieved without heating and using reactive chemicals. The potential application fields includes matrix polymers for controlled-release system and cellincorporated artificial organs, surgical adhesive and dressing.

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We have developed coupling agents with long-chain hydrophilic spacer based on poly (ethylene oxide). These have versatile applications such as surface modification, protein fixation on polymer surfaces and protein modif iciation. The couplers introduced at the end of the spacer include succinimide, pentachlorophenol and imidazole. The resultant activated ester reacts with primary amino group of proteins to result in an increase in molecular weight. SOD (Superoxide dismutase) modified gave a prolonged half-life in rat blood. The bifunctional coupler is much efficient for increase in molecular weight and preservation of enzymatic activity than monofunctional counterparts.

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The polymyxin B fibers, tertianary amine and quaternary ammonium salts were well known as an insoluble antimicrobial materials.
However, the antifungal activity was not included. For the improvements of such drawback, the polysterene fibers which were bonded with iodine or chlorine were investigated respectively in our experimental studies, and especially, the antifungal activity was identified by whether the yeasts still existed or not after put the yeast suspension 10⁶CFU/ml and fibers togather in shaker for 2 hours. Since the results revealed that the yeast were almost undetectable in iodine group and also without the release of iodine in supernate; the feasibility of utilizing iodine immobilized fibers as insoluble antimicrobial material, including antifunal activity, was substantially confirmed.

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We have evaluated the antitumor effect of IL-2 mini-pellet on the therapy of established murine Meth-A sarcoma. The administration of IL-2 mini-pellet alone or IL-2 mini-pellet plus LAK cells was effective in inhibiting the tumor growth and could also prolong the survivals of cancer-bearing mice. The lytic activites of splenocytes against YAC-1 cells and JTC-11 cells were augmented on day 2 after the administration of IL-2 mini-pellet. In histological examination a lot of Thy1⁺ and ASGM1⁺ lymphocytes were invased into tumor tissues on day 7. These results suggested that IL-2 mini-pellet could induce effector cells like LAK cells in vivo at tumor site.

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we have developed new trilayer artificial skin which is composed of the bottom layer of fibrillar collagen and heat-denatured collagen with the dehydrothermal crosslinking, and the central layer of fibrillar collagen with the chemical crosslinking, and the upper layer of a silicon elastmer. In this study, this artificial skin was “grafted” onto fullthickness skin defect of the rats' dorsal surface. 4 weeks after “grafting”, fibroblasts had infiltrated into the bottom layer, and the newly connective tissue composed of fold and wide collagen fiber, so called “pseudo-dermas”, had been formed. The epidermis accompanied with basement membrane migrated from the wound edge just as devided between bottom and central layer, and finally, rete ridge was formed. These results suggest that it is suitable to call it artificial skin proper.

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We investigated the biocompatibility of collagen matrix in a subcutaneous implantation model of rats. The degree of crosslinking was extremely changed the infiltration of cells, the fibrillar collagen (FC) with the chemical crosslinking showed foreign reaction due to the infiltration of neutropils and macrophages, while such reaction was not observed in the dehydrothermally (DHT) crosslinking one. Furthermore, collagen matrix composed of FC and heat denatured collagen (HAC) promoted the infiltration of fibroblasts compared with FC matrix, so MAC may play an important role in the infiltration of fibroblasts. As these results, FC-HAC matrix with DHT crosslinking promoted the reconstruction process of the tissue.

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Surface properties and blood responsibility of chemically modified segmented polyurethanes were investigated for the purpose of the use as anti-thrombogenic biomaterials. Octadecyl-substituted polyurethanes were obtained by homogeneous and heterogeneous reactions. PEO-chainsubstituted polyurethanes were obtained by homogeneous reaction. Surface enrichment of octadecyl groups in air and escaping from the interface under water were observed for octadecyl-substituted surfaces via homogeneous reaction method. On the other hand, no reorganization was observed under water via heterogeneous reaction method, showing that octadecyl groups exist at interface region. This resulted in suppression of platelet adhesion. In PEO-chain-substituted polyurethanes, no enrichment of substituted PEO-chains were observed in air, but hydrated interface was materialized under water. This resulted in much reduced adhesion of Platelet.

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In order to prevent the compications accompanied with pulmonary-artery (Swan-Ganz) catheterization, we have developed Anthron thermodilution catheter which shows excellent antithrombogenicity due to continuose release of heparin from its surface to blood stream in animal experiments. As controls, poly (vinyl chloride) thermodilution catheter was evaluated in the similar manner. All of Anthron thermodilution catheters were completery free of thrombus formation and kept excellent sensing functions for more than 3 days, while in control catheters severe thrombus formations were found both on the surfaces of the catheters and blood vessels. The sensing functions of the control catheters deteriorated with passage of time because of the deposition of the blood constituents on the thermistor.

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Examination with scanning electron microscope in 60 cases confirmed that the HS polymer-coated catheter had a significantly improved antithrombogenetic performance compared with the conventional intravenous catheter. Moreover, there were no catheter-associated complications during hematological studies.

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Between April, 1985 and August, 1988, a total of 124 patients of congenital heart disease were treated using EPTFE (Gore-Tex) patchs.
Hospital mortality was 8.9% (11 deaths) and late mortality was 1.8% (2 deaths) and seemed to be related to operative indication, technical error and fail to postoperative management rather than Gore-Tex patch itself. In the longterm, thromboembolism, anevysmal dilation have not been observed.
Light microscopical observations of patch at late stage showed good formations of neointima, organization of patch and no foreign body reaction.
These results demonstrate that this material is useful to the cardiac operation.

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The in-vivo implantation study was conducted to evaluate the histocompatibility of shape memory alloy in a living body. Kirschner's wire was used as a control, and pins were implated subcutaneously in the dorsal region of two dogs. 2 weeks, 4 weeks, 8 weeks, 4 months and 6 months after the implantation, the pins were removed with the surrounding tissues and evaluated histologically. At 2 weeks, the inflammatory reaction was strong in both groups, at 4 weeks the capsules were formed, and after 8 weeks, neither inflammatory nor foreign body reactions were observed in either group.

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The leakage of fluid from the UBE Woven-Graft (UWG) preclotted with whole blood (A), 25% albumin (B), and no treatmet (C) was studied using closed circuit with pulsatile device and heparinized pump blood. The fluid loss at the initiation and 60 minutes. of circulation was as follows; A: 1.15ml and 0.32ml, B: 25.3ml and 2.1ml, C: 3.5ml and 1.62ml/min. Electron scanning micrography revealed the least lining of blood components in B. It was concluded that UWG preclotted with whole blood was suitable for vascular surgery using CPB.

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