Cytotoxicity of a hybrid prepared by coupling diphtheria toxin A-chain with immunoglobulin Fab' with N,N'-o-phenylenedimaleimide.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to N Ohtomo.
Explore the source record for details and available documents.
The HBeAg was detected in 5 of 24 patients with acute type B hepatitis (20.8%), 33 of 95 with chronic hepatitis (34.7%), 6 of 33 with liver cirrhosis (18.2%), and 3 of 39 with hepatocellular carcinoma (7.7%). On the other hand, anti-HBe was found in 4.2% of acute hepatitis, 18.9% of chronic hepatitis, 9.1% of liver cirrhosis, and 12.8% of hepatocellular carcinoma. We found that an early detection of HBeAg in patients with acute hepatitis is of no prognostic value, but its persistence may provide the earliest evidence of potential chronicity. In chronic liver diseases, HBeAg-positive cases showed remarkable fluctuations of serum transaminase levels, severe histological changes and poor responses to treatment. Many of the HBeAg-positive patients lost their initial positivity of HBeAg within six months or one year and in some cases serocoverted to anti-HBe after acute exacerbation. Follow-up study more than several years revealed that the presence of anti-HBe reflect an inactive stage and a more favorable outcome, whereas persistence of HBeAg may provide an active and continuing hepatocellular damage. From these results, we believed that serial measurements of HBeAg/anti-HBe system are useful prognostic marker in patients with HBsAg-positive liver disease.
For detection of cholera enterotoxin activity, suckling hamster, mouse, and rat models were compared. It was found that not only suckling mice but also suckling rats and hamsters were sensitive to cholera enterotoxin. Among these models, suckling hamsters were the most sensitive and gave positive results with about 1/100 the cholera toxin seen in suckling mice and rats.
Cholera toxin (choleragen) dissociated into two types of subunit with molecular weights estimated to be 28,000 daltons (A) and 11,000 daltons (B); this dissociation was effected by gel filtration at acid pH with or without urea. Subunit A could be separated into two fragments, A1 (23,000 daltons) and A2 (about 2,500 daltons), after reduction and alkylation. Choleragenoid (68,000 daltons) appeared to be a polymerized form of subunit B. A-specific antigen was found in choleragen as well as in A1 and A2, while B-specific antigen was found in both choleragen and choleragenoid. In electron micrographs, the toxin molecule appeared as a particle of uniform size consisting of subunits in V- or Y-shape and in ring form. The dimensions coincided with the values calculated from the molecular weights.
Explore the source record for details and available documents.
Explore the source record for details and available documents.