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The aim of this study was to investigate the sensitizing potential of 12 di(meth)acrylates when tested in the Guinea Pig Maximization Test (GPMT) and Freund's Complete Adjuvant Test (FCAT). In these tests the same (malar) concentration was used for intradermal induction. The results (see table, below) show that dimethacrylates are moderate to strong sensitizers in the guinea pig. In the group of diacrylates, no sensitization to diethylene glycol diacrylate was observed, 1,2-ethenediol diacrylate and 1,6-hezanediol diacrylate sensitized a number of animals. The challenge reaction pattern of the FCAT with 1,4-butanediol diacrylate, neopentane diol diacrylate and 1,5-pentanediol diacylate differed from that commonly observed with sensitizers. Positive reactions were seen only to the maximum non-irritant concentration at 24 h in the challenge at day 21. At 48 h and in the second challenge at day 35, the reactivity had decreased or disappeared. This different reaction pattern makes it difficult to classify these monomers with certainty as sensitizers. In most of the FCATs, a decrease in reactivity in successive challenges was found. Possible explanations for this decrease and for the different challenge reaction patterns of some diacrylates are discussed. The skin irritant capacity of dimethacrylates was estimated after one open application. Diacrylates are very strong irritants on guinea pig skin. Dimethacrylates are weak irritants. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate differences in the sensitizing potential of 14 mono(meth)acrylates, when tested by the guinea pig maximization test (GPMT) and Freund's complete adjuvant test (FCAT) with an identical, intradermal induction concentration. A new grading classification of the sensitization potential is proposed. Mono(meth)acrylates show a wide range of sensitizing potential. Compared with other (meth)acrylates, methyl methacrylate is a moderate sensitizer. Attention was paid to concomitant sensitization of additives. In 9 of 16 FCATs, concomitant sensitization occurred to the inhibitors hydroquinone and p-methoxyphenol. [ABSTRACT FROM AUTHOR]

The transmission of Plasmodium falciparum through Anopheles stephensi was measured in the presence of anti-gamete (anti-45/48 kDa) and anti-zygote/ookinete (anti-25 kDa) antibodies. With lowering numbers of infectious gametocytes in the presence of the same concentration of antibodies, different results were obtained with the two types of antibodies. Transmission blocking appeared to weaken when using anti-45/48 kDa antibody, whilst, with the anti-25 kDa antibody, transmission inhibition was markedly strengthened with lower parasite numbers. Keeping the parasite numbers constant and progressively lowering the concentration of both types of antibodies resulted in a gradual loss of the latters' blocking ability. No enhancement of transmission occurred at low antibody concentrations.

The cross reaction pattern of acrylic monomers was investigated in 20 groups of animals sensitized to a different acrylic monomer. Animals sensitized to one monoacrylate tend to react to other monoacrylates. Reactions to corresponding monomethacrylates (same alcohol group in the ester) or other monomethacrylates did not occur. Some reactions to di(meth)acrylates were observed. A number of animals sensitized to one monomethacrylate reacted to some other monomethacrylates and to monoacrylates. Reactions to di(meth)acrylates were observed. Animals sensitized to di(meth)acrylates showed hardly any positive cross reaction. A universal screening allergen to detect acrylic monomer sensitizations does not exist. The composition of (industrial) products should be made accessible to the occupational dermatologist in order to prevent the undesirable situation in which a patient suspected of having an acrylic monomer sensitization must be tested with a large series of potent allergens in order to detect the real origin of the sensitization.