Assessment of Microbial Diversity in Biofilms Recovered from Endotracheal Tubes Using Culture Dependent and Independent Approaches

Ventilator-associated pneumonia (VAP) is a common nosocomial infection in mechanically ventilated patients. Biofilm formation is one of the mechanisms through which the endotracheal tube (ET) facilitates bacterial contamination of the lower airways. In the present study, we analyzed the composition of the ET biofilm flora by means of culture dependent and culture independent (16 S rRNA gene clone libraries and pyrosequencing) approaches. Overall, the microbial diversity was high and members of different phylogenetic lineages were detected (Actinobacteria, beta-Proteobacteria, Candida spp., Clostridia, epsilon-Proteobacteria, Firmicutes, Fusobacteria and gamma-Proteobacteria). Culture dependent analysis, based on the use of selective growth media and conventional microbiological tests, resulted in the identification of typical aerobic nosocomial pathogens which are known to play a role in the development of VAP, e.g. Staphylococcus aureus and Pseudomonas aeruginosa. Other opportunistic pathogens were also identified, including Staphylococcus epidermidis and Kocuria varians. In general, there was little correlation between the results obtained by sequencing 16 S rRNA gene clone libraries and by cultivation. Pyrosequencing of PCR amplified 16 S rRNA genes of four selected samples resulted in the identification of a much wider variety of bacteria. The results from the pyrosequencing analysis suggest that these four samples were dominated by members of the normal oral flora such as Prevotella spp., Peptostreptococcus spp. and lactic acid bacteria. A combination of methods is recommended to obtain a complete picture of the microbial diversity of the ET biofilm

A Polarised Population of Dynamic Microtubules Mediates Homeostatic Length Control in Animal Cells

An analysis of cells grown on micro-patterned lines, and of cells during zebrafish development, identifies a population of microtubules that align along the long axis of cells to mediate homeostatic length control

Le rôle des services aux entreprises à forte intensité de connaissances dans la compétitivité belge

The share of the service sector in industrialised economies has grown robustly in recent decades. Although this is often linked to the lower productivity trend in this segment, we have seen strong growth in highly productive knowledge-intensive services. We explain the growing importance of knowledge-intensive services for structural competitiveness on the basis of a detailed analysis of the Belgian advice and support services. We examine the most important factors that underlie the strong growth in this segment through Michael Porter's analysis model. We conclude that knowledgeintensive services, which are characterised by strong network effects, play a key role in the knowledge economy by stimulating the transfer of knowledge between sectors; flexibility and specialisation. © De Boeck Supérieur.status: publishe

From Delta to Omicron SARS-CoV-2 variant : switch to saliva sampling for higher detection rate

Background: Real-time polymerase chain reaction (RT-PCR) testing on a nasopharyngeal swab is the current standard for SARS-CoV-2 virus detection. Since collection of this sample type is experienced uncomfortable by patients, saliva- and oropharyngeal swab collections should be considered as alternative specimens. Objectives: Evaluation of the relative performance of oropharyngeal swab, nasopharyngeal swab and saliva for the RT-PCR based SARS-CoV-2 Delta (B.1.617.2) and Omicron (B.1.1.529) variant detection. Study design: Nasopharyngeal swab, oropharyngeal swab and saliva were collected from 246 adult patients who presented for SARS-CoV-2 testing at the screening centre in Ypres (Belgium). RT-PCR SARS-CoV-2 detection was performed on all three sample types separately. Variant type was determined for each positive patient using whole genome sequencing or Allplex SARS-CoV-2 variants I and II Assay. Results and conclusions: Saliva is superior compared to nasopharyngeal swab for the detection of the Omicron variant. For the detection of the Delta variant, nasopharyngeal swab and saliva can be considered equivalent specimens. Oropharyngeal swab is the least sensitive sample type and shows little added value when collected in addition to a single nasopharyngeal swab

Teacher leadership in practice: Mapping the negotiation of the position of the special educational needs coordinator in schools

Special needs care has taken on a substantial evolution within education. Special educational needs coordinators (SENCOs) are no longer considered to provide individual guidance to students but to support and professionalize regular teachers in fulfilling special needs care in their classroom. In doing so, they act as teacher leaders. Many concerns are raised about how teacher leadership may interfere with the existing working relationships in schools. In this study, we use Positioning Theory as a theoretical approach to obtain an in-depth understanding of how the position of the SENCO and the responsibilities attached to this position are negotiated within the school. The findings illustrate that SENCOs received the legitimacy to act as teacher leaders when their expertise was recognized, when teachers perceived their task as first-line helpers, and when school principals were willing to release power.status: publishe

Evolutionary trends of apatites

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