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Asbestos has been widely used on ships as an insulating material due to its fire-resistant and sound-absorbent properties. It was therefore deemed appropriate to measure the concentrations of airborne asbestos fibres on two ferries in regular service on the Civitavecchia-Golfo Aranci route. Decontamination work had been carried out on these vessels in order to remove, as far as possible, or to confine asbestos. Between 1994 and 1998, the Ultrastructures Laboratory of the Istituto Superiore di Sanità analysed 123 samples via scanning electron microscopy (SEM) with elementary dispersion X spectroscopy (EDXS). The results showed that in 98.4% of the samples concentrations in the air were below 2 fibres/litre, which is the value set by Ministerial Decree of 6/9/94 for buildings to qualify for effective decontamination status. Concentrations above this value, between 2 and 10 fibres/litre, were found in one ferry engine room, where workers were not continuously present since a remote control box was installed there. The results show that there is no environmental dispersion of asbestos fibres in usual navigation conditions; the situation is comparable to that in buildings where asbestos-containing safety materials have been used and that are subject to period checks in accordance with the guidelines included in Ministerial Decree of 6/9/94. Legislation is deemed necessary to make law 257/92 applicable to naval vessels in order to define univocal criteria for risk evaluation, checking, maintenance and custody procedures of asbestos-insulated vessels, and procedures for each job on board involving handling or removal of asbestos-containing material.

The type VIII capsular polysaccharide has been isolated and purified from a newly described strain of group B Streptococcus which is a leading cause of sepsis and neonatal meningitis in Japan. The polysaccharide contains D-glucose, D-galactose, L-rhamnose, and sialic acid in the molar ratio 1:1:1:1. By means of high resolution 1H nuclear magnetic resonance (1H NMR), 13C NMR, and homo- and heterocorrelated NMR, the repeating unit structure of the type VIII polysaccharide was delineated as the following, [formula: see text] Enzymatic studies established this polysaccharide as the first from which sialic acid, linked to a branched beta-D-galactopyranosyl residue, is known to be removed by bacterial neuraminidase

Group B streptococci (GBS) are the most common cause of bacterial sepsis and meningitis in neonates in the United States. Although the capsular polysaccharide of GBS is an important virulence factor, it is variably immunogenic in humans. In this report, we have increased the immunogenicity of GBS type II polysaccharide by coupling it to tetanus toxoid (TT). Like other GBS capsular polysaccharides, the type II polysaccharide has side chains terminating in sialic acid. Controlled periodate oxidation of native II polysaccharide resulted in the conversion of 7% of sialic acid residues to an analog of sialic acid, 5-acetamido-3,5-dideoxy-D-galactosyloctulosonic acid. TT was conjugated to free aldehyde groups created on the oxidized sialic acid residues by reductive amination. Serum from rabbits vaccinated with type II-TT conjugate (II-TT) vaccine contained antibodies specific to type II polysaccharide as well as to TT, whereas rabbits vaccinated with uncoupled native type II polysaccharide failed to produce a type-specific antibody response. Antibodies elicited by II-TT vaccine were serotype specific and mediated phagocytosis and killing in vitro of type II GBS by human peripheral blood leukocytes. Serum from rabbits vaccinated with II-TT vaccine provided 100% protection in a mouse model of GBS type II infection. Antibodies induced by II-TT vaccine were specific for the native but not desialylated type II polysaccharide, suggesting that an important antigenic epitope of II-TT vaccine was dependent on the presence of sialic acid. Therefore, the coupling strategy which selectively modified a portion of the sialic acid residues of types II polysaccharide before coupling the polysaccharide to TT preserved the epitope essential to protective immunity and enhanced the immunogenicity of the polysaccharide.