Role of idiotype-anti-idiotype interactions in the induction of collagen-induced arthritis in rats.

The mechanism of autoantibodies (rheumatoid factor (RF) and anti-collagen autoantibodies) induction in collagen-induced arthritis (CIA) is unknown. The study assessed the hypothesis that activation of autoantibody-producing clones is mediated by idiotype-anti-idiotype (IAI) interactions with lymphocytes on heterologous collagen. It was demonstrated that RF-containing serum of rats immunized with bovine collagen (BCII) in ELISA competes with BCII for binding to anti-BCII antibodies.

Tetramerization of 3-methyl-cyclopropene-3-carbonitrile: a novel CN-alder-ene reaction.

At elevated temperatures 3-methyl-cyclopropene-3-carbonitrile 1 was found to tetramerize giving compound 2 (3-methyl-2,3-bis(2-t-methyl-2-c-cyanocyclopropyl)-1-(2-t-methyl-2-c,3-c-dicyanocyclopropyl)-cyclopropene) in good yields. This is the first example of Alder-ene type oligomerization of a 3,3-disubstituted cyclopropene. On the basis of the product geometry and stereoselective character of the reaction, a mechanism of formation of 2 involving CN-Alder-ene reaction was proposed.

[Age factor in eye regeneration of the gastropod mollusk Achatina fulica].

The dependence of the ability to regenerate the eye on the age of experimental animals was studied in the snail Achatina fulica. The degree of regeneration was estimated by light-microscopic and electrophysiological methods and by analyzing the motor response to visual stimuli. In older age groups, the number of regenerated eye-bearing tentacles decreased, whereas the period of regeneration increased.