[A survey on occupational health nursing activities and evaluation in TOHOKU area].

We did a mail survey in 1998 in Tohoku district. We sent questionnaires to approximately 300 Occupational Health (OH) nurses and got 132 replies. Occupations of respondents were 66 public health nurses and 57 nurses. More than 70% did not have a managerial position. About 40% were respondents without colleagues in nursing occupations. Full time occupational physicians were in 40% of companies, and semi-full time occupational physicians were in 60%. Respondents citing good coordination in the former were 60%, and in the latter were 80%. Of all business activities occupying OH nursing employees, persons who performed more than 90% of the tasks numbered more than 30%. Persons not satisfied with present employment positions were 80%. Reasons for dissatisfaction in declining order of incidence were work duties, contract conditions for employment, and personal relations. Planning and summary of OH nursing activities were carefully done highly. For the OH nursing activity evaluation, we examined guidelines for business locations by observing them from the OH nursing aspect and the OH nursing job itself. Guidelines considered for business locales from the OH nursing vantage point show numerically, for example, rates of examinees with abnormal findings, work absenteeism, etc, and expectations as to whether or not health conditions are conspicuously reflected in productivity. Conversely, from the OH nursing vantage point for guidelines on business locales, while receiving affirmative economic evaluation of occupational health and safety measures, progress (process) should also be included in the object of evaluation. Furthermore, guidelines should be mindful of the need to have qualitative and quantitative changes in health behavior of workers and perspectives on health.

Preparation of a diphtheria toxin-pullulan conjugate that elicits good IgG antibody production with poor IgE synthesis.

Diphtheria toxin is detoxified through conjugation with pullulan. The toxin-pullulan conjugate is easily purified by DEAE-Sephacel chromatography. The conjugate forms a transparent 'clear line' with anti-toxin antibodies on agarose plate, which offers a good indicator of conjugate formation. The toxin-pullulan conjugate induces both IgG1 and IgG2b antibody production with diminished IgE response, while the alum-precipitated conventional toxoid causes mainly increases in IgE as well as IgG1 antibody formation. The anti-toxin HA titre (IgG antibody) induced by the toxin-pullulan conjugate parallels the neutralizing activity of the immune-sera. These results suggest that the conjugation of toxin to pullulan is a very powerful method by which to develop a vaccine that induces neutralizing antibody with diminished IgE antibody synthesis.

'Clear line' formation by immunodiffusion of tetanus toxoid and mixtures of distinct monoclonal antibodies.

Single monoclonal antibodies could not form any precipitin line with tetanus toxoid in Ouchterlony analysis. However, some mixtures of two distinct monoclonal antibodies formed a visible precipitin line (conventional line), while others formed a transparent, just barely visible line, which we call a 'clear line'.

Microcapsule agglutination test for Treponema pallidum antibodies. A new serodiagnostic test for syphilis.

For the serodiagnosis of syphilis a quantitative passive agglutination (MCA-TP) test for antibodies to Treponema pallidum was performed with chemically stable microcapsules with no antigenic activity instead of with conventional sheep erythrocytes. The microcapsules were easily sensitised with the antigen of sonicated Treponema pallidum by treatment with glutaraldehyde. Compared with the Treponema pallidum haemagglutination test (TPHA) the MCA-TP test was superior for detecting cases of primary syphilis. Furthermore, the decrease in antibody titre during treatment was more evident in this test than in the FTA-ABS or the TPHA tests. The MCA-TP test performed on IgM and IgG gel-filtered fractions of sera from patients with syphilis proved that the sensitised microcapsule antigen reacted sharply with the IgM antibodies specific to syphilis.

In vitro aggregation of platelets induced by alpha-toxin (phospholipase C) of Clostridium perfringens.

Highly purified alpha-toxin (phospholipase C) of Clostridium perfringens prepared by affinity chromatography on agarose-linked egg-yolk lipoprotein induced the in vitro aggregation of platelets of an irreversible type. The aggregation started after a time lag, the length of which depended on the concentration of the toxin; the reciprocal of the time lag was found to be directly proportional to the toxin concentration. Using this assay method, we demonstrated that the platelet-aggregating activity of alpha-toxin reached minimum at around 70 C but heating at higher temperatures inactivated it to a lesser extent; the same anomaly in heat inactivation was observed with phospholipase C activity possessed by the toxin. By subjecting purified alpha-toxin to isoelectric focusing, four molecular forms were isolated, all of which were associated with both the platelet-aggregating and phospholipase C activities. From all these results we concluded that the entity responsible for the platelet-aggregating activity is identical with alpha-toxin (phospholipase C).