To investigate the relationship between job-stress and medical consultation rates for physical illness, a prospective study was conducted for male blue workers of an electrical factory in Japan. 8 job-stress variables and 8 possible confounders were assessed by means of mailed questionnaires in the initial study; 375 workers without medical history of illness were followed for four years; they were interviewed once a year and medical consultations for physical illness were recorded. Age-adjusted rates of medical consultation during the four-year period were significantly higher in the subjects with higher job-dissatisfaction scores than in those with lower job-dissatisfaction scores (p < 0.05). The results of the multiple logistic regression analysis indicated that job-dissatisfaction together with age and education was significantly correlated with medical consultation (p < 0.05). The results sug-gest that job-dissatisfaction is a potential factor for medical consultation in Japanese blue collar workers.
The reduction of 20 μM hexavalent chromium [chromium(VI)] in single-reductant solutions of 0.02-2 mM L-ascorbic acid (L-AsA) or 2 mM reduced glutathione (GSH), and in mixed solutions of 2 mM GSH containing L-AsA of the above-described concentrations was investigated at physiological pH (370°C). The reduction of chromium(VI) in the L-AsA solutions of higher concentrations showed pseudo-first-order kinetics in a single phase with respect to chromium(VI). In the lower L-AsA concentrations, pseudo-first-order processes appeared only in an early stage of the reaction. The reduction in the GSH solution was characterized by a two-phase process. In the first phase, which appeared in very short duration, the reaction rate was much higher than that in the second, but resulted in a decrease of only 7% of the initial chromium(VI) level. The second phase showed the main process of the reduction. This indicated pseudo-first-order kinetics. The half-life values of chromium(VI) depended on the initial levels of the reductants and ranged from seconds to hours. The chromium(VI)-reducing ability of L-AsA was markedly higher than that of GSH. In the mixed solutions of L-AsA and GSH, synergistic effect on the reduction of chromium(VI) was observed, especially in earlier stages of the processes. The synergism was more conspicuous in the mixed solutions containing lower L-AsA levels. These results suggest that although AsA possesses higher reducing ability than GSH, their coexistence is of importance for the reduction of chromium(VI) in biological systems because of their synergism.
Mercuric chloride (MC) was administered to mice subcutaneously 3 times a week for 4 weeks. When inbred BALB/c, CBA/JN, C3H/He, C57BL/6 and DBA/2 and outbred ICR female mice were given 1 mg/kg MC, 8 of 10 ICR mice developed antinucleolar autoantibodies (AnuA) of the IgG class but none of the inbred mice produced AnuA. So the ICR mice were used in the following experiments. In a kinetic study, in which mice were given 1.5 mg/kg MC, the positivities and titers of AnuA increased time-dependently, and were kept at high levels until 8 weeks after the final treatment. The AnuA titers of mice receiving 0.5-2.0 mg/kg increased dose-dependently, while the positivity was similar at all dosages. The antibody titers were higher in mice pretreated with an intramuscular injection of either complete or incomplete Freund's adjuvant. The titer increase was more prominent in mice administered doses lower than 0.5 mg/kg. Neither nude mice nor mice treated with a monoclonal antibody to L3T4 (GK1.5) developed AnuA. These results indicate that the induction of AnuA by MC depend primarily on L3T4-positive T cells.