A life-threatening anaphylactoid reaction to polyvalent snake antivenom despite pretreatment.

A 44-year-old man suffered a life-threatening anaphylactoid reaction to polyvalent snake antivenom, although he had been given the recommended pretreatment. Further research is needed to determine if pretreatment is necessary.

Alginate as immobilization matrix and stabilizing agent in a two-phase liquid system: application in lipase-catalysed reactions.

Alginate was evaluated as an immobilization matrix for enzyme-catalyzed reactions in organic solvents. In contrast to most hydrogels, calcium alginate was found to be stable in a range of organic solvents and to retain the enzyme inside the gel matrix. In hydrophobic solvents, the alginate gel (greater than 95% water) thus provided a stable, two-phase liquid system. The lipase from Candida cylindracea, after immobilization in alginate beads, catalysed esterification and transesterification in n-hexane under both batch and continuous-flow conditions. The operational stability of the lipase was markedly enhanced by alginate entrapment. In the esterification of butanoic acid with n-butanol, better results were obtained in the typical hydrophilic calcium alginate beads than in less hydrophilic matrices. The effects of substrate concentration, matrix area, and polarity of the substrate alcohols and of the organic solvent on the esterification activity were examined. The transesterification of octyl 2-bromopropanoate with ethanol was less efficient than that of ethyl 2-bromopropanoate with octanol. By using the hydrophilic alginate gel as an immobilization matrix in combination with a mobile hydrophobic phase, a two-phase liquid system was achieved with definite advantages for a continuous, enzyme-catalysed process.

Animal carotenoids. 32. Carotenoids of Mytilus edulis (edible mussel).

Nineteen different carotenoids have been isolated from various harvests of Mytilus edulis (edible mussels). Besides beta,beta-carotene (occasional) these were ten acetylenic C40-carotenoids: crocoxanthin-like, anhydro-amarouciaxanthin B, 19'-hexanoyloxyisomytiloxanthin, isomytiloxanthin, alloxanthin, mytiloxanthin, amarouciaxanthin B-like, halocynthiaxanthin, pectenol-like and heteroxanthin; two acetylenic C37-carotenoids: pyrrhoxanthinol and hydrato-pyrrhoxanthinol; four C40-skeletal allenic carotenoids: 19'-hexanoyloxyfucoxanthin, fucoxanthin, 19'-hexanoyloxyfucoxanthinol and fucoxanthinol; two C37-skeletal allenic carotenoids: peridinin and peridininol. Anhydro-amarouciaxanthin B, 19'-hexanoyloxyisomytiloxanthin (minor occasional) and hydrato-pyrrhoxanthinol constitute new carotenoids. The characterization comprised TLC and HPLC behaviour, VIS spectrophotometry, 1H NMR (including full assignment of three new carotenoid end groups), CD and mass spectra, as well as chemical derivatizations. Stereochemical considerations are discussed.

Muscle sarcomere length following passive jaw opening in the rabbit.

Sarcomere lengths were measured microscopically in formalin-fixed jaw muscles of 14 rabbits divided into two groups; jaw open, and jaw closed. The measurements were compared by means of a nested analysis of variance. The sarcomeres of the jaw open group were longer in the masseter and temporalis muscles (jaw elevators) and shorter in the digastric muscle (jaw depressor) than were those of the jaw closed group. In the jaw closed position, sarcomeres in the deep portion of the masseter muscle become markedly shorter than those in the superficial part of the muscle. The values for sarcomere length in the masseter muscle of the jaw open group and the digastric of the jaw closed group are near the top of the ascending limb of isometric length-tension relation for the rabbit digastric muscle.

Bacterial carotenoids. L. Absolute configuration of zeaxanthin dirhamnoside.

Zeaxanthin dirhamnoside is the major carotenoid of Corynebacterium autotrophicum. The absolute configuration 3R,3'R followed from CD-properties of its hexaacetate, alpha-L-assignment and 1C4 conformation were concluded from 1H NMR data by comparison with model compounds.