Quantitative testing of corrosion rates of heritage steel coated with Paraloid B72™, Cosmolloid 80H™ and Siliglide 10™

Within conservation practice a few specific coatings are utilised for a very wide range of applications, based mostly on sketchy evidence of their long term performance, ageing properties, ethical factors such as reversibility and aesthetic considerations that include transparency. Hence the acrylic copolymer Paraloid B72 and the microcrystalline wax Cosmolloid 80H are extensively used as indoor and outdoor coatings across a broad spectrum of metals from archaeological to historical contexts. Evidence of their performance is largely qualitative, based on observations made in environments with uncontrolled and often unmonitored variables. This approach is suited to recording performance in real life storage and display contexts but it lacks reproducibility and does not deliver insight into how specific variables such as relative humidity, application methodology, surface preparation and contaminants impact on coating performance. This study examines the performance of Paraloid B72, Cosmolloid 80H and a silane polymer Siliglide 10, as protective coatings on modern steel continuously exposed to fixed high humidity. Test samples were cut from the rear door of a Saracen armoured personnel vehicle circa 1950’s. Coating procedure was carefully controlled and assessed to offer both standardisation and alignment with commonly used application procedures in the heritage sector. Similarly, surface preparation was uniform and standardised. Both uncontaminated and chloride contaminated surfaces are used as test platforms for the coatings. Long exposure periods of months to years were employed. Quantitative data is collected by measuring the oxygen consumption of individual samples in controlled relative humidity. The rationale was to deliver evidence of how these coatings may perform in conditions where relative humidity can reach high levels but there is no direct exposure to rain, thus including open shelters and uncontrolled stores used to store historic and industrial objects. The research programme aimed to deliver practical outputs for project partners and end users at the Tank Museum Bovington UK and Historic Scotland. The Arts and Humanities Research Councils sponsored the study. Results to date indicate that all three coatings perform similarly on surfaces that are cleaned. On surfaces that have undergone chloride contamination post-cleaning the silane was best at preventing corrosion, measured by oxygen consumption followed by Paraloid B72 then Cosmolloid 80H

Nox2 in regulatory T cells promotes angiotensin II–induced cardiovascular remodeling

The superoxide-generating enzyme Nox2 contributes to hypertension and cardiovascular remodeling triggered by activation of the renin-angiotensin system. Multiple Nox2-expressing cells are implicated in angiotensin II (AngII)-induced pathophysiology, but the importance of Nox2 in leukocyte subsets is poorly understood. Here, we investigated the role of Nox2 in T cells, particularly Tregs. Mice globally deficient in Nox2 displayed increased numbers of Tregs in the heart at baseline whereas AngII-induced T-effector cell (Teffs) infiltration was inhibited. To investigate the role of Treg Nox2, we generated a mouse line with CD4-targeted Nox2 deficiency (Nox2fl/flCD4Cre+). These animals showed inhibition of AngII-induced hypertension and cardiac remodeling related to increased tissue-resident Tregs and reduction in infiltrating Teffs, including Th17 cells. The protection in Nox2fl/flCD4Cre+ mice was reversed by anti-CD25 Ab-depletion of Tregs. Mechanistically, Nox2-/y Tregs showed higher in vitro suppression of Teffs proliferation than WT Tregs, increased nuclear levels of FoxP3 and NF-κB, and enhanced transcription of CD25, CD39, and CD73. Adoptive transfer of Tregs confirmed that Nox2-deficient cells had greater inhibitory effects on AngII-induced heart remodeling than WT cells. These results identify a previously unrecognized role of Nox2 in modulating suppression of Tregs, which acts to enhance hypertension and cardiac remodeling

Review of public personnel administration

Background Adrenaline is the primary drug of choice for resuscitation from out-of-hospital cardiac arrest (OHCA). Although adrenaline may increase the chance of achieving return of spontaneous circulation (ROSC), there is limited evidence that repeated doses of adrenaline improves overall survival, and increasing evidence of a detrimental effect on neurological function in survivors. This paper reports the relationship between repeated doses of adrenaline and survival in a cohort of patients attended by the London Ambulance Service in the United Kingdom. Methods A retrospective review of OHCA treated by the London Ambulance Service over a one year period. Patients aged ≥18 years who received one or more doses of adrenaline (1 mg bolus) during resuscitation were included in the analyses. Outcomes described are survival to hospital discharge and survival to one year post-arrest. Results Over the one year study period, 3151 patients received adrenaline during OHCA. A significant inverse relationship was found between increasing cumulative doses of adrenaline and survival both to hospital discharge and one year post-arrest. No patients survived after receiving more than ten adrenaline doses. Conclusion Our study indicates that repeated doses of adrenaline are associated with decreasing odds of survival. There were no survivors amongst patients requiring more than 10 doses of adrenaline