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Background: Contaminated nebulizers are a potential source of bacterial infection but no single method is universally accepted for disinfection. We hypothesized that baby-bottle steam sterilizers effectively disinfect home nebulizers., Methods: Home nebulizers were inoculated with the common CF respiratory pathogens methicillin resistant Staphylococcus aureus, Burkholderia cepacia, Haemophilus influenzae, mucoid and non mucoid Pseudomonas aeruginosa, and Stenotrophomonas maltophilia. The nebulizers were swabbed for bacterial growth, treated with either the AVENT (Philips), the NUK Quick & Ready (Gerber) or DRY-POD (Camera Baby) baby bottle steam sterilizer and reswabbed for bacterial growth., Results: All steam sterilizers were effective at disinfecting all home nebulizers. Viable bacteria were not recovered from any inoculated site after steam treatment, under any conditions tested., Conclusions: Steam treatment is an effective disinfection method. Additional studies are needed to confirm whether these results are applicable to the clinical setting., (Copyright © 2012 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.)

Two partial mRNA sequences predicted to encode anti-lipopolysaccharide factors (ALFs) were identified among expressed sequence tags generated from the American lobster Homarus americanus and complete cDNA sequences were obtained from library clones. Comparison of the translated amino acid sequences to those publicly available confirmed similarity to arthropod anti-lipopolysaccharide factors. Both protein sequences, designated ALFHa-1 and ALFHa-2, contained an N-terminal signal peptide and two half-cysteines participating in a disulfide bridge, features conserved in other ALFs. Predicted secondary structures were similar to that described for the ALF from the horseshoe crab Limulus polyphemus. As part of an exploratory study of immunity in H. americanus, lobsters were injected with the bacterium Vibrio fluvialis and gill, hematopoietic, and hepatopancreas tissues were sampled for analysis of gene expression of ALFHa-1 and ALFHa-2 by quantitative PCR. The relative abundance of ALFHa-2 mRNA was not significantly affected by Vibrio injection in any of the three tissues tested. In contrast, ALFHa-1 mRNA levels in gills were increased by the treatment some 17-fold. Our results support a molecularly specific regulation of antimicrobial proteins in response to bacterial infection in H. americanus., (2008 Elsevier Inc. All rights reserved.)

Astacus leptodactylus is a decapod crustacean fully adapted to freshwater where it spends its entire life cycle after hatching under huge osmoconcentration differences between the hemolymph and surrounding freshwater. We investigated the expression of mRNA encoding one ion transport-related protein, Na(+)/K(+)-ATPase alpha-subunit, and one putative housekeeping gene, beta-actin, during crayfish ontogenesis using quantitative real-time PCR. A 216-amino acid part of the open reading frame region of the cDNA coding for the Na(+)/K(+)-ATPase alpha-subunit was sequenced from total embryo, juvenile and adult gill tissues. The predicted amino acid sequence showed a high percentage similarity to those of other invertebrates (up to 95%) and vertebrates (up to 69%). beta-actin expression exhibited modest changes through embryonic development and early post-embryonic stage. The Na(+)/K(+)-ATPase alpha-subunit gene was expressed in all studied stages from metanauplius to juvenile. Two peaks of expression were observed: one in young embryos at 25% of embryonic development (EI=100 mum), and one in embryos just before hatching (at EI=420 mum), continuing in the freshly hatched juveniles. The Na(+)/K(+)-ATPase expression profile during embryonic development is time-correlated with the occurrence of other features, including ontogenesis of excretory antennal glands and differentiation of gill ionocytes linked to hyperosmoregulation processes and therefore involved in freshwater adaptation.

It is thought that a plasma membrane Ca(2+)-transport ATPase (PMCA) and a Na(+)/Ca(2+)-exchange (NCE) mechanism are involved in epithelial Ca(2+) transport (ECT) in a variety of crustacean epithelia. The sternal epithelium of the terrestrial isopod Porcellio scaber was used as a model for the analysis of Ca(2+)-extrusion mechanisms in the hypodermal epithelium. Using RT-PCR, we amplified a cDNA fragment of 1173 bp that encodes a protein sequence possessing 72% identity to the PMCA from Drosophila melanogaster and a cDNA fragment of 791 bp encoding a protein sequence with 50% identity to the NCE from Loligo opalescens. Semiquantitative RT-PCR revealed that the expression of both mRNAs increases from the non-Ca(2+)-transporting condition to the stages of CaCO(3) deposit formation and degradation. During Ca(2+)-transporting stages, the expression of PMCA and NCE was larger in the anterior sternal epithelium (ASE) than in the posterior sternal epithelium (PSE). The results demonstrate for the first time the expression of a PMCA and a NCE in the hypodermal epithelium of a crustacean and indicate a contribution of these transport mechanisms in ECT.