The Bacteriophage T4 MotB Protein, a DNA-Binding Protein, Improves Phage Fitness.

The lytic bacteriophage T4 employs multiple phage-encoded early proteins to takeover the Escherichia coli host. However, the functions of many of these proteins are not known. In this study, we have characterized the T4 early gene motB, located in a dispensable region of the T4 genome. We show that heterologous production of MotB is highly toxic to E. coli, resulting in cell death or growth arrest depending on the strain and that the presence of motB increases T4 burst size 2-fold. Previous work suggested that motB affects middle gene expression, but our transcriptome analyses of T4 motBam vs. T4 wt infections reveal that only a few late genes are mildly impaired at 5 min post-infection, and expression of early and middle genes is unaffected. We find that MotB is a DNA-binding protein that binds both unmodified host and T4 modified [(glucosylated, hydroxymethylated-5 cytosine, (GHme-C)] DNA with no detectable sequence specificity. Interestingly, MotB copurifies with the host histone-like proteins, H-NS and StpA, either directly or through cobinding to DNA. We show that H-NS also binds modified T4 DNA and speculate that MotB may alter how H-NS interacts with T4 DNA, host DNA, or both, thereby improving the growth of the phage.

Behavioral Effects and Tunneling Responses of Eastern Subterranean Termites (Isoptera: Rhinotermitidae) Exposed to Chlorantraniliprole-Treated Soils.

Intrinsic toxicities of chlorantraniliprole, fipronil, and imidacloprid were evaluated with topical applications on worker termites. Worker termites were exposed to substrates treated with formulated chlorantraniliprole to study contact toxicity, tunneling, and postexposure behaviors. The intrinsic toxicities (LD50, ng/termite) of chlorantraniliprole (1.25, 0.96, and 0.44) and fipronil (0.12, 0.11, and 0.13) at 11 d were similar for workers from three termite colonies. Imidacloprid toxicity (LD50) values were highly variable among the workers from three different colonies, values at 11 d ranging from 0.7 to 75 ng/termite. Termite workers exposed to sand and soils treated with chlorantraniliprole at 50 ppm exhibited delayed mortality and, for most of the exposure times, it took >5 d to observe 90-100% mortality in termite workers. Exposure to chlorantraniliprole-treated sand (50 ppm) for as little as 1 min stopped feeding and killed 90-100% of the workers. Tunneling (≈ 2 h) in different soil types treated with chlorantraniliprole at 50 ppm, even those with high organic matter (6.3%) and clay content (30%), caused immediate feeding cessation in worker termites and mortality in the next 7-14 d. Worker termites exposed for 1 and 60 min to sand treated with chlorantraniliprole (50 ppm) were able to walk normally for 4 h after exposure in most cases. Delayed toxicity, increased aggregation, and grooming were observed in exposed termites and discussed in the context of horizontal transfer effects within termite colonies.

A new oxygen prescription produces real improvements in therapeutic oxygen use.

In the UK, safe use and administration of oxygen therapy was unsatisfactory prior to the implementation of national guidelines in 2008. Each year since then the British Thoracic Society (BTS) has conducted a national audit that has demonstrated a slow but steady improvement in oxygen use across four key standards. Sandwell and West Birmingham NHS Hospitals Trust has participated in this audit process but has failed to show consistent improvements. The aim of this quality improvement project was to produce meaningful and sustained improvements in oxygen use across each of the four standards. Four interventions were developed over three PDSA cycles and included: 1. a new oxygen prescription chart, 2. oxygen 'alert' stickers for use on drug and MEWS charts, 3. point of care resources, and 4. senior led educational sessions for healthcare staff. Each intervention was tested on the Acute Medical Unit over seven days and data collected using the BTS data collection form. The QIP improved oxygen use across each of the standards: baseline measurement for standard one demonstrated that 55% of patients using oxygen had a valid oxygen prescription, improving to 94% after PDSA cycle three. For standard two, baseline measurement demonstrated that 50% of patients had a documented oxygen target saturation range, improving to 94% after PDSA cycle three. For standard three, baseline measurement demonstrated that 84% patients using oxygen had saturations documented on the MEWS chart, improving to 100% after PDSA cycle three. Finally, baseline measurement of standard four demonstrated that 0% patients with a valid oxygen prescription had it signed for at drugs rounds, improving to 18% after PDSA cycle three. Oxygen use was substantially improved during the QIP. Following engagement with stakeholders a new oxygen prescription will be rolled out within the Trust with projected annual savings of £30,400.