Adaptation to Antimicrobials and Pathogenicity in Mycoplasmas: Development of Ciprofloxacin-Resistance and Evolution of Virulence in Acholeplasma laidlawii.

For the first time it was shown that the development of resistance to ciprofloxacin in vitro in Acholeplasma laidlawii, a mycoplasma which is widely spread in nature and which is the main contaminant of cell cultures and vaccines, is associated with diverse pathways of virulence evolution: virulome and virulence differ significantly between ciprofloxacin-resistant strains, including those with the same level of antimicrobial resistance.

Preparation of Pickering emulsions stabilized by metal organic frameworks using oscillatory woven metal micro-screen.

Uniform Pickering emulsions stabilized by metal organic frameworks (MOFs) MIL-101 and ZIF-8 nanoparticles (NPs) were successfully prepared using an oscillatory woven metal microscreen (WMMS) emulsification system in the presence and the absence of surfactants. The effects of operating and system parameters including the frequency and amplitude of oscillation, the type of nano-particle and/or surfactant on the droplet size and coefficient of variance of the prepared emulsions are investigated. The results showed that both the hydrodynamics of the system and the hydrophobic/hydrophilic nature of the NP influenced the interfacial properties of the oil-water interface during droplet formation and after detachment, which in turn affected the final droplet size and distribution. Comparison between the measured and predicted droplet size using a simple torque balance (TB) model is discussed.

Qualitative study of perceived causes of tuberculosis treatment default among health care workers in Morocco.

SETTING: In Morocco, tuberculosis (TB) treatment default is increasing in some urban areas. OBJECTIVE: To provide a detailed description of factors that contribute to patient default and solutions from the point of view of health care professionals who participate in TB care. DESIGN: In-depth interviews were conducted with 62 physicians and nurses at nine regional public pulmonary clinics and local health clinics. RESULTS: Participants had a median of 24 years of experience in health care. Treatment default was seen as a result of multilevel factors related to the patient (lack of means, being a migrant worker, distance to treatment site, poor understanding of treatment, drug use, mental illness), medical team (high patient load, low motivation, lack of resources for tracking defaulters), treatment organization (poor communication between treatment sites, no systematic strategy for patient education or tracking, incomplete record keeping), and health care system and society. Tailored recommendations for low- and higher-cost interventions are provided. CONCLUSIONS: Interventions to enhance TB treatment completion should take into account the local context and multilevel factors that contribute to default. Qualitative studies involving health care workers directly involved in TB care can be powerful tools to identify contributing factors and define strategies to help reduce treatment default.

Molecular characterisation of rifampicin-resistant Mycobacterium tuberculosis strains from Morocco.

Mutations in the rpoB gene associated with rifampicin (RMP) resistance were studied in 47 RMP-resistant and 147 RMP-susceptible clinical strains of Mycobacterium tuberculosis from Morocco using probe-based assay and DNA sequencing. RMP-resistant mutations were identified in 85% of RMP-resistant isolates. No mutations were observed among the 147 RMP-susceptible strains. Sequence analysis identified 10 alleles, including two deletions not previously reported. Nucleotide changes at codons 531, 526 and 516 were the most prominent, accounting for 74.4% of our RMP-resistant strains. These results demonstrate that resistance genotyping at these codons would be a good marker for the rapid detection of RMP resistance.