The modification of the standard rubella haemagglutination-inhibition (HAI) test using trypsin-treated human group O erythrocytes instead of chick erythrocytes was evaluated. In a comparative study we found that, of 816 samples tested by both methods, the titres of 807 (98.9%) sera were in close agreement within an acceptable twofold difference. Trypsin-treated human group O erythrocytes usuall...

The Montecarlo method is used to computer simulate a random distribution of molecular lengths generated by inducing T4 DNA fragmentation through the decay of 32P atoms introduced in the molecule. Taking into account the experimental conditions we find that the value of alpha for alkali sucrose gradients is 0.46 +/- 0.02 and does not depend on the running time. Our findings also prove that the c...

background and objectives: virosomes are virus like particles (vlp) assembled in-vitro. influenza virosomes maintain the cell binding and membrane fusion activity of the wild type virus but are devoid of viral genetic material or internal proteins. influenza virosomes mimic the natural antigen presentation route of the influenza virus. materials and methods: virosomes were prepared by membrane ...

A comparison was made of the performance of swing-out and vertical ultracentrifuge rotors in the detection of rubella-specific IgM on a sucrose density gradient. Tests were performed on 30 sera, of which 11 were found to contain rubella-specific IgM by both methods. The centrifugation time for the swing-out rotor was 16 hours at 35,000 rpm. This was reduced to 2 hours using the vertical rotor a...

Mass distribution in a sucrose gradient of deoxyribonucleic acid (DNA) fragments arising as a result of random breaks is predicted by analytical means from which computer evaluations are plotted. The analytical results are compared with the results of verifying experiments: (i) a Monte Carlo computer experiment in which simulated molecules of DNA were individuals of unit length subjected to ran...

Microbodies from rat liver and a variety of plant tissues were osmotically shocked and subsequently centrifuged at 40,000 g for 30 min to yield supernatant and pellet fractions. From rat liver microbodies, all of the uricase activity but little glycolate oxidase or catalase activity were recovered in the pellet, which probably contained the crystalline cores as many other reports had shown. All...