Immune mechanisms of the occupational sensitization with methylen-dyphenyl diisocyanate (MDI).

The aim of this study was to objectify and to clarity some mechanisms of the immune response of the professional sensitization with MDI. 26 workers were tested for sensitization of immediate type (ST with a broad set of indoor allergens and serum MDI-IgE) and of delayed type (ST with a standard battery of antigens for cellular immunity and with MDI), also the lymphocyte sub-populations and their functional state by flow cytometric analysis. The most frequent allergic complaints were: rhinits (70%), skin manifestations (53%), conjunctivitis (35%) and initial bronchial asthma in two cases (12%). We found indoor sensitization in 41% and normal cellular immune reactivity in all the workers tested. Specific MDI sensitization of immediate type was found in 28.5% of the workers and of delayed type--in 70% of the workers with allergic complaints. The laboratory immune indices suggest prevalence of cell--mediated mechanisms for the workers with allergic symptoms--production of INF gamma, responding to stimulation and deficient or insignificant production of IL-4, as well as linear correlation between the data for CMI, INF gamma, and IL-4. Our results suggest the participation of more than one mechanism of immune injury in the clinically manifested allergic reactions.

[Presence of salmonellae and coliform bacteria in ground meat and the sources of its contamination]. / Prouchvaniia vurkhu nalichieto na salmonelni i koliformni bakterii v mliano meso i izotochnitsii za kontaminiraneto mu.

Studied were a total of 14,944 samples of minced meat for the presence of Salmonellae and 608 samples for establishing the coli-titer. Examined were also bacteriologically 5651 washing samples from the workers' hands, the machines, equipment and stock implements in the shops for the production of minced meat prior to starting work as well as 3721 washing samples from the same for the presence of coliforms. It was found that 1.81 per cent of 14,188 samples of minced meat were contaminated with as many as 17 serotypes of Salmonella organisms belonging to the B, C and E serogroups. It was believed that the primary source of Salmonellae in minced meat were the clinically normal Salmonella carrier animals apart from the occasional contamination during the individual technologic stages of processing. The smallest amount of minced meat in which coli bacteria (titer) could be found varied within the range of 0.01 to 0.0001, 53 out of the investigated 608 samples, i. e. 8.72 per cent showing a titer of 0.01, 477 samples (78.45 per cent) having a titer of 0.001, and 78 samples (12.88 per cent) having a titer of 0.0001. Of the examined samples washings 25.69 were positive for coli bacteria, and 0.27 per cent--for Salmonella bacteria, which spoke of improper disinfection.