Early Biofilm Formation on Rough and Smooth Titanium Specimens: a Systematic Review of Clinical Studies.

Objectives: There is a concern whether the enhancement on implant surface roughness is responsible for higher biofilm formation, which acts as an aetiological factor for peri-implant diseases. The aim of the present systematic review was to answer the following question: "Are rough surfaces more susceptible to early biofilm formation when compared to smoother surfaces on titanium specimens?".

Material And Methods: The research was performed on PubMed, Web of Science and Scopus, up to August 2021.

Effectiveness of nanoparticles solutions and conventional endodontic irrigants against biofilm.

Context: To overcome the challenge imposed by the presence of biofilm and reach significant bacterial reduction of the root canals, many irrigants have been indicated during endodontic treatment, among them nanoparticles solutions.

Aims: This study aims to evaluate the effectiveness of experimental solutions containing silver and zinc oxide nanoparticles (ZnO Np) and conventional endodontic irrigants against Enterococcus faecalis biofilm, in root canals.

Methods: Seventy-six extracted human teeth were biomechanically prepared and sterilized.

Synthetic organic compounds with potential for bacterial biofilm inhibition, a path for the identification of compounds interfering with quorum sensing.

New unconventional approaches to the development of antimicrobial drugs must target inhibition of infection stages leading to host colonisation or virulence itself, rather than bacterial viability. Amongst the most promising unconventional targets for the development of new antimicrobial drugs is bacterial adherence and biofilm formation as well as their control system, the quorum-sensing (QS) system, a mechanism of communication used to co-ordinate bacterial activities. Here we describe the evaluation of synthetic organic compounds as bacterial biofilm inhibitors against a panel of clinically relevant Gram-positive and Gram-negative bacterial strains.

From insects to human hosts: Identification of major genomic differences between entomopathogenic strains of Photorhabdus and the emerging human pathogen Photorhabdus asymbiotica.

Pathogenic bacteria of the genus Photorhabdus are naturally found in symbiotic association with soil entomopathogenic nematodes, and are of increasing economic interest in view of their potential for the development of novel biopesticides. This bipartite natural system is currently used for the biological control of crop pests in several countries. However, an increasing number of Photorhabdus strains have recently been isolated from human clinical specimens in both the United States and Australia, associated with locally invasive soft tissue infections and disseminated bacteraemia.

In vitro identification of two adherence factors required for in vivo virulence of Pseudomonas fluorescens.

By enriching a random transposon insertion bank of Pseudomonas fluorescens for mutants affected in their adherence to the human extracellular matrix protein fibronectin, we isolated 23 adherence minus mutants. Mutants showed a defect in their ability to develop a biofilm on an abiotic surface and were impaired for virulence when tested in an in vivo virulence model in the fruit fly, Drosophila melanogaster. Molecular characterisation of these mutants showed that the transposon insertions localised to two distinct chromosomal locations, which were subsequently cloned and characterised from two mutants.