Biomedical subjects

K Numa

Publications and source records attributed to K Numa.

6 recordsLinked to original sources

PubMed1992

[Innovative elastomeric bio-adhesive (pup-201) synthesized by urethane-prepolymer].

Properties of PUP-201 for the application to vital organs were estimated. Basic properties of PUP-201 were compared with two kinds of commercial fibrin and synthetic adhesives. Its initial and wet adhesive strength was 40 and 150 times stronger than those of fibrin adhesives respectively. Its curing time was 50 seconds, and elongating rate was 150% nearly as same as that of the intestine. This adhesive had not antimicrobial activities. The strength of adhesive bonded pig skin in shear by tension loading by way of JIS K6850 recorded 2.0-2.7kg/cm2 five minutes after, and 2.0-2.8kg/cm2 after 24 hours. The results of the same test in small intestine defined 0.4-1.0kg/cm2 in sero-sero attachment. There was no toxicity on the pig skin. Practical examinations for application to hemostasis on the section of dog liver and sealing of the lung section were performed successfully. PUP-201 was demonstrated excellently useful material for the adhesive, hemostasis and sealant of vital tissue.

Animals↗

PubMed1991

[Hemoadsorption].

Explore the source record for details and available documents.

Hemoperfusion↗

PubMed1990

Trial of anticancer immunotherapy with immobilized pokeweed mitogen: immunotherapy by extracorporeal circulation.

For the purpose of activating the immune system in the living body, we made use of pokeweed mitogen (PWM). PWM, a type of lectin, has the potential to induce anticancer cells. In order to utilize this potential and apply it to cancer therapy by hemoperfusion with PWM, the lectin is immobilized on the surface of synthetic polymer beads and these beads are packed into a minicolumn. Human peripheral lymphocytes were activated by circulatory contact stimulation through the PWM column for 1h. After circulatory contact stimulation through the column, lymphocytes were collected and used as effector cells. Cytotoxicity tests were measured by 51Cr-release assay using K-562 cells and Daudi cells for targets. This material could enhance natural killer activity and induce cytotoxicity against natural-killer-resistant Daudi cells. Lymphocytes activated by the PWM column were injected intraregionally into nude mice bearing MKN-1 tumor, and suppression of tumor growth was recognized. Anticancer activities by direct hemoperfusion treatment with a PWM minicolumn were examined in Vx2-tumor-bearing rabbits. A single treatment using the PWM column was performed 6 days after tumor inoculation. Suppression of the tumor growth was observable for 25 days. PWM minicolumns are a likely anticancer material, acting as immunomodulators.

Animals↗

PubMed1990

Therapeutic plasmapheresis for post-operative hepatic failure.

It goes without saying that post-surgical hepatic failure must be treated. But today, the prognosis is very poor. The reasons for this are that HF is usually accompanied by hemostatic disorders and PHF, and the patients have fresh wounds and are under surgical stress. Moreover, there is no treatment, except PE, and this requires an anticoagulant. Nafamostat Mesilate (FUT-175) was invented as a serine protease inhibitor. It is short acting, and its degradation does not require the liver. FUT-175 was applied as an anticoagulant to 15 PHF patients with bleeding. There were no side effects and no aggravation of bleeding. Based on these results, FUT-175 is thought to be an ideal anticoagulant.

Anticoagulants↗

PubMed1989

Experimental study on the adsorption of excess heparin with anion exchange resin fiber.

Anion exchange resin fiber (Ionex) was used as a heparin adsorbent. Ionex has the adsorption capacity of 70 mg/g (weight by desiccation) for heparin, and was used in an attempt to remove the heparin from blood-perfused artificial organs, before the blood was transfused back into the patients. In the ex vivo study, the 5 systemically heparinized dogs (500 U/kg) were treated with a 35-40 g column of Ionex, by direct hemoperfusion (DHP). The concentration of heparin was significantly reduced, within 15 to 60 minutes, using the Ionex. This suggested the possibility of removing excess heparin from the living body. In in vitro, the relationship between the amount of heparin by Ionex and the blood-flow volume were evaluated. Whole blood taken from dogs was added to 5 U/ml of heparin. This was then introduced into a small column containing 0.9 g Ionex, at blood-flow rates of 0.8, 1.6, and 3.2 ml/min. A good adsorption capacity was shown at the blood-flow rate of 0.8 ml/min. One possible explanation for this is that the heparin dispersed in the blood cells gradually was passed on into the plasma and, so, did not have time to be adsorbed at the faster flow rates.

Adsorption↗

PubMedDate not supplied

The efficiency of new leukocyte removal filters. CF-1 and CF-2.

Two new leukocyte removal filters, Nipro CF-1 and CF-2 (Nipo Medical Industries, Osaka, Japan), were evaluated. These non-woven polyester filters, which are gravity flow devices that require no priming and no rinsing after use, were developed for preparing 400 ml of whole blood or red cell concentrates from 400 ml of whole blood. A flow cytometric technique was developed to measure extremely low white blood cell (WBC) counts. To evaluate the efficiency of these filters, leukocyte counts were measured by three techniques: 1) electronic, 2) visual, and 3) flow cytometry. Flow cytometric counting was done using a Coulter EPICS-C cytometer (Coulter Corp., Hialeah, FL). Nipro CF-1 removed 99.97 +/- 0.01% (mean +/- SD, n = 14) of leukocytes measured by flow cytometry, and CF-1 recovered 90.7 +/- 4.47% (n = 21) of red blood cells. After filtration through CF-2, more than a 6 log10 (> 99.9999%) depletion of WBCs was detected in six samples, a 6 log10 (99.9999%) depletion of WBCs was detected in two samples, a 5 log10 (99.999%) depletion was detected in five samples, and a 4 log10 (99.99%) depletion was detected in one sample. CF-1, in which size and priming volume was smaller than other commercial leukocyte removal filters, accomplished a 3 log10 reduction in WBC count, compared with other commercial filters. CF-2 achieved a 4-6 log10 depletion of WBCs assayed by flow cytometry.

Blood Transfusion↗