A Burkholderia pseudomallei Toxin Inhibits Helicase Activity of Translation Factor eIF4A

This is the author accepted manuscript. The final version is available from American Association for the Advancement of Science via the DOI in this record.The structure of BPSL1549, a protein of unknown function from Burkholderia pseudomallei, reveals a similarity to Escherichia coli cytotoxic necrotizing factor 1. We found that BPSL1549 acted as a potent cytotoxin against eukaryotic cells and was lethal when administered to mice. Expression levels of bpsl1549 correlate with conditions expected to promote or suppress pathogenicity. BPSL1549 promotes deamidation of glutamine-339 of the translation initiation factor eIF4A, abolishing its helicase activity and inhibiting translation. We propose to name BPSL1549 Burkholderia lethal factor 1

The Pathophysiology of Inhalational Brucellosis in Balb/c Mice

To characterize the clinical presentation and pathophysiology of inhalational brucellosis, Balb/c mice were challenged with Brucella melitensis 16M in a nose-only aerosol exposure chamber. A low dose of 1000 cfu/animal of B. melitensis resulted in 45% of mice with tissue burdens eight weeks post-challenge. The natural history of brucellosis in mice challenged by higher aerosol doses was examined by serial euthanizing mice over an eight week period. Higher challenge doses of 1.00E+05 and 5.00E+05 cfu resulted in positive blood cultures 14 days post-challenge and bacterial burdens were observed in the lung, liver and/or spleens 14 days post-challenge. In addition, the progression of brucellosis was similar between mice challenged by the intranasal and aerosol routes. The results from this study support the use of the Balb/c aerosol nose-only brucellosis mouse model for the evaluation of therapeutics against inhalational brucellosis

The impact of patient feedback on the medical performance of qualified doctors: a systematic review

Background: Patient feedback is considered integral to quality improvement and professional development. However, while popular across the educational continuum, evidence to support its efficacy in facilitating positive behaviour change in a postgraduate setting remains unclear. This review therefore aims to explore the evidence that supports, or refutes, the impact of patient feedback on the medical performance of qualified doctors. // Methods: Electronic databases PubMed, EMBASE, Medline and PsycINFO were systematically searched for studies assessing the impact of patient feedback on medical performance published in the English language between 2006-2016. Impact was defined as a measured change in behaviour using Barr’s (2000) adaptation of Kirkpatrick’s four level evaluation model. Papers were quality appraised, thematically analysed and synthesised using a narrative approach. // Results: From 1,269 initial studies, 20 articles were included (qualitative (n=8); observational (n=6); systematic review (n=3); mixed methodology (n=1); randomised control trial (n=1); and longitudinal (n=1) design). One article identified change at an organisational level (Kirkpatrick level 4); six reported a measured change in behaviour (Kirkpatrick level 3b); 12 identified self-reported change or intention to change (Kirkpatrick level 3a), and one identified knowledge or skill acquisition (Kirkpatrick level 2). No study identified a change at the highest level, an improvement in the health and wellbeing of patients. The main factors found to influence the impact of patient feedback were: specificity; perceived credibility; congruence with physician self-perceptions and performance expectations; presence of facilitation and reflection; and inclusion of narrative comments. The quality of feedback facilitation and local professional cultures also appeared integral to positive behaviour change. // Conclusion: Patient feedback can have an impact on medical performance. However, actionable change is influenced by several contextual factors and cannot simply be guaranteed. Patient feedback is likely to be more influential if it is specific, collected through credible methods and contains narrative information. Data obtained should be fed back in a way that facilitates reflective discussion and encourages the formulation of actionable behaviour change. A supportive cultural understanding of patient feedback and its intended purpose is also essential for its effective use

Comparative experimental subcutaneous glanders and melioidosis in the common marmoset (Callithrix jacchus)

© 2014 Company of the International Journal of Experimental Pathology (CIJEP). Glanders and melioidosis are caused by two distinct Burkholderia species and have generally been considered to have similar disease progression. While both of these pathogens are HHS/CDC Tier 1 agents, natural infection with both these pathogens is primarily through skin inoculation. The common marmoset (Callithrix jacchus) was used to compare disease following experimental subcutaneous challenge. Acute, lethal disease was observed in marmosets following challenge with between 26 and 1.2 × 108 cfu Burkholderia pseudomallei within 22-85 h. The reproducibility and progression of the disease were assessed following a challenge of 1 × 102 cfu of B. pseudomallei. Melioidosis was characterised by high levels of bacteraemia, focal microgranuloma progressing to non-necrotic multifocal solid lesions in the livers and spleens and multi-organ failure. Lethal disease was observed in 93% of animals challenged with Burkholderia mallei, occurring between 5 and 10.6 days. Following challenge with 1 × 102 cfu of B. mallei, glanders was characterised with lymphatic spread of the bacteria and non-necrotic, multifocal solid lesions progressing to a multifocal lesion with severe necrosis and pneumonia. The experimental results confirmed that the disease pathology and presentation is strikingly different between the two pathogens. The marmoset provides a model of the human syndrome for both diseases facilitating the development of medical countermeasures