Neo re cells (NRC) are oxygen carrier which are prepared by transforming stroma, free hemoglobin (SFH) nd llosteric effector into liposome.
Appropriate molar ratio to Hb of inositol hexaphosphate (IHP) which is one of allosteric effector was investigated by, observin efficacy of NRC for rabbits receiving extensive blood exchange. P₅₀ value of NRC without IHP is nearly same as that of SFH and then rabbits infused the NRC died for 16-18hrs, because of low oxgen delivery to peripheral tissue. On the other hand, the rabbits infused the NRC containing IHP, molar ratio of 0.5-1.5 to Hb, survived for 24hrs. In these rabbits blood lactate concentration returned to normal condition gust after infusion. Body temperature, blood pH and PvO₂ were recovered raduall. Arterial pressure and continuous urinary output were normal. Oxygen carrying capacity of these NRC was nearly equal to that of erythrocytes. NRC which contained IHP, molar ratio of 1.5 to Hb took calcium cation from plasma. Considering these results appropriate molar ratio of IHP to Hb may be 0.5-1.0.

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Lipid-heme solution transports molecular oxygen under physiological condition. A rabbit was connected with a respirator and was ventilated with 10% oxygen (F_Io₂=0.1). Oxygen saturation (So₂) and oxygen partial pressure (Po₂) of the venous blood were measured. When the rabbit was ventilated at F_Io₂=0.1, Svo₂ was reduced to 20%. The infusion of the lipid-heme solution saturated with oxygen into the abdominal cavity enhanced Svo₂ up to 60%.
Exchange-transfusion of the lipid-heme solution to a dog was carried out with the rate of 10ml/min. Po₂ of the mixed venous increased from 30 to 44mmHg after the transfusion of the lipid-heme solution. The total blood flow (cardiac output) was 0.73l/min. The oxygen delivering amount or consumption (Vo₂) of the lipid-heme solution and of blood were calculated to be 9.2 and 50ml/min, respectively, which were corresponding to the intravascular concentrations of the lipid-heme and the red blood cell. Oxygen transporting ability of the lipid-heme solution was discussed.

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The sensitivity of the electromagnetic flowmetry applied to vascular grafts was analyzed in a mock circulatory loop. The Wyatt's formula was applied to an electrical analog model of a graft with the graft parameters estimated from the measured electrical resistance. The theoretical prediction agreed well with the experimental sensitivity. The measured sensitivities were independent of the flow rate. This result assumes the reliability of electromagnetic flowmetry as applied to vascular grafts.

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This study was designed to elucidate the mechanism of synthetic tetrapeptide, RGDS (Arg-Gly-Asp-Ser) as a novel antiplatelet agent, in which RGDS was recently identified as a common amino acid sequence of adhesive site of adhesive proteins. The results showed: 1) RGDS binds the membrane receptor of platelets, 2) RGDS inhibits dose-dependently the platelet aggregation, and 3) The release of ATP and elevation of intracellular calcium ions was dose-dependently inhibited only via ligand-receptor mechanism.

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We assess the efficacy of double filtration plasmapheresis (DFP) in decreasing hepatitis B virus associated antigens and it was intruded to the clinical use in 13 cases of chronic hepatitis type B (9 cases with HBeAg, 4 cases without HBeAg) in order to decrease serum HBeAg and HBV which may act as inhibitors for host immune response. In HBeAg positive cases elevation of serum GPT was observed after DFP and subsequently serum DNA-P activity become negative in 2 cases. A remarkable increase of serum HBV related antigens and DNA-P activity was observed after DFP, especially in cases with a relatively low DNA-P activity and in patients treated in combination with interferon. On the other hand such changes were not observed in HBeAg negative cases. These suggest that DFP treatment for HBeAg positive chronic hepatitis type B may induce HBV replication and improve host immune response. Application of DFP to immunotherapy in chronic hepatitis type B will be a useful clinical methods. Double filtration plasmapheresis, chronic hepatitis type B

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A clinical evaluation was made in 12 patients. The use of the Autotransfusion system had favorable results, compared with the 23 patients who underwent similer operation without autotransfusion. 1350ml of homologous blood were reduced satisfactorily on the average in a patient with abdominal aortic aneurysm and 1500ml in thoracic aortic aneurysm. Five of 8 patients with abdominal aortic aneurysm received no homologous blood during the operations. There were no perioperative death. Hemolysis and slight elevation of serum creatinine level were noted in a few patients, but no renal failure were occurred. No other complications were observed. The use of autotransfusion system during major vascular surgery is seem to be effective to reduce the amount of homologous blood transfusion.

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We studied the effect of autologous blood transfusion (ABT) to reduction of homologous blood transfusion (HBT) and prevention of post transfusion hepatitis. Method of ABT consists of re-utilization of concentrated blood by using concentrator, intraoperative hemorrhage and blood in the circuit after bypass by using Haemonetics Cell Saver III, and post operative shed mediastinal blood. The volume of HBT and number of donors was reduced from 2538.9±1408.6ml, 14.4±9.8 donors to 1395.8±831.9ml, 7.3±6.0 donors by these ABT and recognition to reduce HBT. As a result, post transfusion hepatitis was decreased from 22.4% to 9.4%. Further reduction of priming volume in the circuit brought the reduction of HBT and number of donors (1772.7±880.6→968.7±527.3ml, 9.6±7.2→4.7±2.7 donors) and the decrease of incidence of post transfusion hepatitis (17.6%→0%). We consider that active utilization of ABT in addition to recognition to reduce HBT and reduction of priming volume is effective to decrease of incidence of post transfusion hepatitis.

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We developed an intraoperative autotransfusion system. The system is simple, inexpensive, and troublefree, consisting of suction tube, cardiotomy reserver filter and gather blood bag. The method of autotransfusion was as follows. After systemic heparinization (2mg/kg), hemorrhaged blood was sucked and collected into the gather bag and this collected blood was reinfused by gravitation. Using this system, we operated on ten patients with abdominal aortic aneurysm. Half of the patients (group I: G I) received no homologous blood during and after surgery, and the of her 5 patients (group II: G II) need homolorous blood transfusion. These two groups were compared with 5 similar patients (group III: G III) in whom conventional transfusion techniques were used. The amounts of shed blood were 2190±960 (Mean±SD) ml in G I, 3160±1940ml in G II, and 1870±750ml in G III. The amounts of shed blood were comparable among these three groups. Total (auto+homo) transfused blood was 1320±400ml in G I, 2440±1760ml in G II, and 1850±690ml in G III. The autotransfused blood was 1320±400ml in G I and 1590±1630ml in G II. Therefore, the autotransfusion blood amounted to 100% in G I, and 60% in G II of the total transfused blood, and amounted to 64% in G I and 46% in G II of the total shed blood. Plasma hemoglobin level was higher and platelet counts were smaller in G II than in G I. However renal failure, infection and respiratory failure did not occur in G II as well as in G I. From these points of view, we conclude that our intraoperative autotransfusion system is safe and useful in major vascular surgery.

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This paper addresses to report the chronic toxicological evaluation of surgical adhesive based on a urethane prepolymer. The chronic toxicological evaluation of coated adhesives on Wister rat liver and subcutaneous tissues showed that cured adhesives are completely biodegraded within 3 to 6 months and that no abnormal tissue growth was observed for 38 rats in 20 monthsimplantation. The prepolymer based on fluorinated aliphatic diisocyanate, which AMES test proved to be negative, is the most promissing adhesive with least carcinogenic potential as well as enhanced biodegradation and adhesional properties.

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In vivo studies on the histotoxicity and bonding strength of subcutaneous tissues of rabbit have been performed using the mixtures of ethoxyethyl cyanoacrylate (EECA) and isobutyl cyanoacrylate (IBCA) with D, L-lactide polymer (PLA) as surgical adhesives. Skin incision made on the back of 30 rabbits was treated with the mixtures and animals were sacrificed at various times postoperatively. The tissues were excised and processed for microscopic examination and also subjected to a bonding test. The studies showed that the mixtures were easier to manipulate as surgical adhesives and had much fewer chances in failing in gluing tissues than the original cyanoacrylates (CA) in the operations. No significant differences were noted in inflammatory response and bonding strength between the original CA and their mixtures with PLA. The inflammatory response of the tissues was less for the IBCA mixtures than that for the EECA mixtures, but the rate of healing and disappearance of CA polymers were slower for the IBCA mixtures. The bonding strength of the tissues treated with those mixtures showed the same tendency that both of the mixtures maintained a constant strength for the first 7 days after operation and increased steeply during the next week.

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To evaluate the possibility of laser welding for biological vascular graft, we anastomosed the graft to canine femoral and caratid arteries by Nd-YAG laser with contact method. This welding successed all cases except one and patency rate was 100%, These anastomotic sites were strong enough for high pressure and fused well without no damage of internal layer, In conclusion, Nd-YAG laser with contact method could successfully weld heparinized biological vascular grafts.

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Experimental vascular anastomosis using glutide copolymer (lactide:glycolide, 80:20) as an external splint was undertaken in 24 dogs. The vessel was transected and introduced into a glutide pipe-sprint. The wall of vessel was turned back 180° over the edge of the sprint. This reflected part of the vessel and the glutide were covered with the freed-up distal side of the vessel. The one knot anastomosis was completed with circular ligature over the vessels. The right carotid arteries in 13 dogs were anastomosed using glutide and the left carotid arteries of the same dogs were anastomosed by hand suture. Another 11 dogs underwent autogenous venous grafting in juglar vein. The proximal site was anastomosed by the one knot anastomosis and the distal site was anastomosed by the hand suture. The patency rate at the anastomosed site was 100%, except initial 2 grafts, confirmed by angiography and/or by autopsy. Light microscopic and scanning electromicroscopic obsevation showd relatively good enodothelialization of intima at the anastomotic site. This technique is cosidered to be clinically applicable.

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