Dental hygienists and infection control: knowledge, attitudes and behaviour in Italy.

This study evaluated knowledge, attitudes and behaviour regarding infection control of dental hygienists in Italy. Among the 185 responders to the self-administered mailed questionnaire, 91.3% agreed with the correct responses to the three questions on knowledge about infection prevention and control procedures chosen as an indicator of 'good' knowledge. However, 21% were uncertain whether, or disagreed that, dental instruments should be rinsed in water after contact with glutaraldehyde and 17.5% agreed that, or were uncertain whether, 10 min contact with glutaraldehyde provided sterilization. Only 36.5% knew all the five oral manifestations of acquired immunodeficiency syndrome (AIDS) (acute periodontal problems, candidiasis, hairy leukoplakia, herpes simplex virus, Kaposi's sarcoma) and this knowledge was significantly higher in dental hygienists with a lower number of years of practice. More than two-thirds used a steam sterilizer or glutaraldehyde for appropriate times and temperatures for disinfection/sterilization of instruments and used appropriate surface disinfection procedures. The correct application of disinfection or sterilization methods for instruments was more likely in the older respondents and in those who attended continuing education courses on infection control. A positive attitude was reported by the majority of dental hygienists who agreed that guidelines should be maintained and applied and was significantly more likely in younger respondents. Only 57.9% routinely follow all recommendations for infection control practices and their use was significantly higher in the older respondents. Educational programmes are needed for improving knowledge about oral manifestations of AIDS in order to support dentists to provide early diagnosis and about the correct use of procedures and universal precautions for preventing infections.

Nitric oxide inhibits the synthesis of type-II collagen without altering Col2A1 mRNA abundance: prolyl hydroxylase as a possible target.

The addition of human recombinant interleukin-1beta (IL-1beta) to cultures of lapine articular chondrocytes provoked the synthesis of large amounts of NO and reduced the production of type-II collagen. NG-Monomethyl-l-arginine (L-NMA), an inhibitor of NO synthase, strongly suppressed the production of NO and partially relieved the inhibition of collagen synthesis in response to IL-1beta. The NO donor S-nitrosoacetylpenicillamine (SNAP), on the other hand, inhibited collagen production. IL-1 lowered the abundance of Col2A1 mRNA in an NO-independent manner. Collectively, these data indicate that IL-1 suppresses collagen synthesis at two levels: a pretranslational level which is NO-independent, and a translational or post-translational level which is NO-mediated. These effects are presumably specific as L-NMA and SNAP had no effect on total protein synthesis or on the distribution of newly synthesized proteins between the cellular and extracellular compartments. Prolyl hydroxylase is an important enzyme in the post-translational processing of collagen, and its regulation and cofactor requirements suggest possible sensitivity to NO. Extracts of cells treated with IL-1 or SNAP had lower prolyl hydroxylase activity, and L-NMA was partially able to reverse the effects of IL-1. These data suggest that prolyl hydroxylase might indeed be a target for NO. Because underhydroxylated collagen monomers fail to anneal into stable triple helices, they are degraded intracellularly. Inhibition of prolyl hydroxylase by NO might thus account for the suppressive effect of this radical on collagen synthesis.

Quantitation of proteins on Coomassie blue-stained polyacrylamide gels based on spectrophotometric determination of electroeluted dye.

A procedure for quantitating proteins on Coomassie blue-stained polyacrylamide gels is presented. The method is based on the observations that the dye is rapidly eluted electrophoretically from stained protein bands or spots in the presence of sodium dodecyl sulfate, and that the eluted dye is nondialyzable. Protein may therefore be assayed indirectly by measuring the dye in electroeluents spectrophotometrically. Moreover, the stain elutes more rapidly than the protein, allowing separate recovery of the protein for further analysis. The assay is independent of band or spot size, and does not involve physical disruption of the gel piece or any chemical treatment harsher than the staining process itself. The technique has been applied to the contractile proteins myosin, actin, and commercially obtained standards resolved by one-dimensional electrophoresis, and to proteins in nuclear extracts of HeLa cells on two-dimensional gels.