Evolution and host-specific adaptation of .

The major human bacterial pathogen causes multidrug-resistant infections in people with underlying immunodeficiencies or structural lung diseases such as cystic fibrosis (CF). We show that a few environmental isolates, driven by horizontal gene acquisition, have become dominant epidemic clones that have sequentially emerged and spread through global transmission networks over the past 200 years. These clones demonstrate varying intrinsic propensities for infecting CF or non-CF individuals (linked to specific transcriptional changes enabling survival within macrophages); have undergone multiple rounds of convergent, host-specific adaptation; and have eventually lost their ability to transmit between different patient groups.

Comprehensive global genome dynamics of show ancient diversification followed by contemporary mixing and recent lineage expansion.

is the world's most prevalent bacterial sexually transmitted infection and leading infectious cause of blindness, yet it is one of the least understood human pathogens, in part due to the difficulties of in vitro culturing and the lack of available tools for genetic manipulation. Genome sequencing has reinvigorated this field, shedding light on the contemporary history of this pathogen. Here, we analyze 563 full genomes, 455 of which are novel, to show that the history of the species comprises two phases, and conclude that the currently circulating lineages are the result of evolution in different genomic ecotypes.

Genome-Based Infection Tracking Reveals Dynamics of Clostridium difficile Transmission and Disease Recurrence.

Background: Accurate tracking of Clostridium difficile transmission within healthcare settings is key to its containment but is hindered by the lack of discriminatory power of standard genotyping methods. We describe a whole-genome phylogenetic-based method to track the transmission of individual clones in infected hospital patients from the epidemic C. difficile 027/ST1 lineage, and to distinguish between the 2 causes of recurrent disease, relapse (same strain), or reinfection (different strain).

Characterization of the yehUT two-component regulatory system of Salmonella enterica Serovar Typhi and Typhimurium.

Proteins exhibiting hyper-variable sequences within a bacterial pathogen may be associated with host adaptation. Several lineages of the monophyletic pathogen Salmonella enterica serovar Typhi (S. Typhi) have accumulated non-synonymous mutations in the putative two-component regulatory system yehUT.

Emergence and global spread of epidemic healthcare-associated Clostridium difficile.

Epidemic C. difficile (027/BI/NAP1) has rapidly emerged in the past decade as the leading cause of antibiotic-associated diarrhea worldwide. However, the key events in evolutionary history leading to its emergence and the subsequent patterns of global spread remain unknown.

Evidence in court: witness preparation and cross-examination style effects on adult witness accuracy.

Witnesses play a clear and pivotal role in the criminal justice system and there is an obvious public interest in identifying procedures that both undermine and maximize the quality of evidence received by the criminal courts. This paper reports an investigation into the effects of witness familiarization and cross-examination type on adult witness accuracy that situates outcomes in both legal and psychological context. 60 mock witnesses observed a crime event and each witness was then cross-examined by a practising barrister in a moot courtroom according to two conditions - either via a scripted complex version of cross-examination or by a simpler but equivalent scripted examination.

Meeting the mental health needs of people with chronic obstructive pulmonary disease: a qualitative study.

Objectives: This study aimed to understand the mental health needs of people living with chronic obstructive pulmonary disease: what they were experiencing, what they wanted (or did not want) which might be described as 'felt need', what they had accessed or received ('expressed need') and how, from their perspective, their emotional needs might be more effectively met by health care services.

Methods: Qualitative study with 14 patients with a confirmed diagnosis of chronic obstructive pulmonary disease, where a member of the clinical team had recognised that the patient was suffering from associated emotional distress.

Results: Three themes emerged: a sense of assuming a different identity as the disease challenged abilities, the experience of social isolation with fear of dependence and barriers the participants encountered acting as obstacles to coping, adapting and accessing treatments.