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INTRODUCTION: Out-of-hospital cardiac arrest (OHCA) is a major public health problem, leading to a substantial number of deaths in the UK. In response to this, the Yorkshire Ambulance Service NHS Trust (YAS) has introduced red arrest teams (RATs). RAT members attend a three-day training course, focusing on the technical and non-technical skills that are required to effectively team lead an OHCA and provide high quality post-resuscitation care. This evaluation aims to determine the impact of the RATs on survival to 30 days and return of spontaneous circulation (ROSC) at hospital. METHODS: All adult (≥ 18 years) OHCAs entered onto the YAS computer aided dispatch (CAD) system between 1 October 2015 and 30 September 2017 were included if the patient was resuscitated and the cause of the arrest was considered to be medical in origin. Multi-variable logistic regression models were created to enable adjustment for common predictors of survival and ROSC. RESULTS: During the 2-year data collection period, YAS attended 15,151 cardiac arrests. After removing ineligible cases, 5868 cardiac arrests remained. RATs attended 2000/5868 (34.1%) incidents, with each RAT attending a median of 13 cardiac arrests (IQR 7-23, min. 1, max. 78).The adjusted odds ratios suggest that a RAT on scene is associated with a slight increase in the odds of survival to 30 days (OR 1.01, 95% CI 0.74-1.38) and odds of ROSC on arrival at hospital (OR 1.13, 95% CI 0.99-1.29), compared to the odds of not having a RAT present, although neither result is statistically significant. CONCLUSION: The presence of a RAT paramedic was associated with a small increase in survival to 30 days and ROSC on arrival at hospital, although neither were statistically significant. Larger prospective studies are required to determine the effect of roles such as RAT on outcomes from OHCA.
RESUMEN
The type III secretion system is used by pathogenic Yersinia to translocate virulence factors into the host cell. A key component is the multifunctional LcrV protein, which is present on the bacterial surface prior to host cell contact and up-regulates translocation by blocking the repressive action of the LcrG protein on the cytosolic side of the secretion apparatus. The functions of LcrV are proposed to involve self-interactions (multimerization) and interactions with other proteins including LcrG. Coiled-coil motifs predicted to be present are thought to play a role in mediating these protein-protein interactions. We have purified recombinant LcrV, LcrG, and site-directed mutants of LcrV and demonstrated the structural integrity of these proteins using circular dichroism spectroscopy. We show that LcrV interacts both with itself and with LcrG and have obtained micromolar and nanomolar affinities for these interactions, respectively. The effects of LcrV mutations upon LcrG binding suggest that coiled-coil interactions indeed play a significant role in complex formation. In addition, comparisons of secretion patterns of effector proteins in Yersinia, arising from wild type and mutants of LcrV, support the proposed role of LcrG in titration of LcrV in vivo but also suggest that other factors may be involved.