Diffusible Signal Factor (DSF)-dependent quorum sensing in pathogenic bacteria and its exploitation for disease control

Cell-to-cell signals of the Diffusible Signal Factor (DSF) family are cis-2-unsaturated fatty acids of differing chain length and branching pattern. DSF signalling has been described in diverse bacteria to include plant and human pathogens where it acts to regulate functions such as biofilm formation, antibiotic tolerance and the production of virulence factors. DSF family signals can also participate in interspecies signalling with other bacteria and interkingdom signaling such as with the yeast Candida albicans. Interference with DSF signalling may afford new opportunities for the control of bacterial disease. Such strategies will depend in part on detailed knowledge of the molecular mechanisms underlying the processes of signal synthesis, perception and turnover. Here, I review both recent progress in understanding DSF signalling at the molecular level and prospects for translating this knowledge into approaches for disease control.

Alcohol consumption among university students: a typology of consumption to aid the tailoring of effective public health policy

Objective: Elevated levels of alcohol consumption among university students are well documented. Policymakers have attempted to combat this issue at a university, national and international level. Tailoring public health policy to effectively tackle alcohol use is crucial. Using Q-methodology, the current study aims to develop a typology of alcohol consumption in the Irish university student population. Setting: A large Irish university. Participants Hundreds of possible statements on types of consumption were generated from a systematic review and a set of one-on-one interviews. These were reduced to 36 statements, 6 statements which define each of the 6 previously defined consumption types. Participants were advised to scan through the 36 statements and fill the statements into a ‘forced choice, standardised distribution’. Following this, a 45–90 min interview was conducted with students to illuminate subjectivity surrounding alcohol consumption. Analysis was conducted using PQ Method and NVivo software. Principal component analysis, followed by varimax rotation, was conducted to uncover the final factor information. Results: In total, 43 students completed the Q-study: 19 men and 24 women. A typology describing 4 distinct groupings of alcohol consumer was uncovered: the guarded drinker, the calculated hedonist, the peer-influenced drinker and the inevitable binger. Factor loadings of each of the consumer groupings were noted for type description. Conclusions: This is the first study to propose ideal types of alcohol consumption among a university student population. Further research is required to investigate the degree to which each of these ideal types is subscribed. However, this typology, in addition to informing public policy and strategies, will be a valuable analytic tool in future research.