Anions and arrhythmias in experimental heart disease

Ischaemic heart disease can cause sudden cardiac death from ventricular arrhythmias occuring as a consequence of ischaemia itself, or as a consequence of subsequent reperfusion of ischaemic tissue. Current agents designed to prevent these arrhythmias do not provide adequate protection. Conventionally, antiarrhythmic agents are subdivided into four classes on the basis of actions on 3-adrenoceptors, or on membrane currents carried by cations. We have explored the modulation of anions as a possible new approach to the prevention of sudden cardiac death. Using an isolated rat heart model, we showed that substitution of the chloride anion by nitrate protects against ischaemia- and reperfusion-induced arrhythmias in a concentration-dependent manner without deleterious haemodynamic consequences. Studies of the site of action demonstrated that (i) protection against ischaemia-induced VF resulted largely from an action in the ischaemic zone, and (ii) protection against reperfusion-induced VF resulted principally from an action occurring during reperfusion and within the reperfused tissue. Significant reductions in ventricular arrhythmias were produced by anions with membrane permeabilities greater than chloride and the 'anion, methylsulphate, which is less permeable than chloride was proarrhythmic. These findings strongly support the hypothesis that altered membrane permeability may contribute to the antiarrhythmic activity of some anion surrogates. In conclusion, anions appear to play a hitherto unrecognized role in arrhythmogenesis in ischaemia and reperfusion. Their manipulation represents a novel target for antiarrhythmic agents

The Development of a Prison Mental Health Unit in England: Understanding Realist Context(s).

A pragmatic solution for the provision of care for prisoners with serious mental illness, who are often subject to delays in hospital transfer, is the creation of specialist prison units. This paper analyses the development of a prison unit in England for prisoners with ‘serious mental illness’. The unit was developed within over-lapping health and justice contexts, including expectations, pressures and priorities, which impacted on the outcomes expected and achieved. The methodology included attendance at Steering group meetings, analysis of a minimum dataset, and interviews with key stakeholders. A number of key sites of contestation are analyzed including: admission criteria; aims; activities; staffing; the physical environment; and discharge

The Effects of the Changes in Section 317 Rules for Administration of Federally Purchased Vaccines

Section 317 of the Public Health Services Act is a federal program that provides funds for the purchase of vaccines. These annual Congressional allocations fluctuate from year to year as Congress responds to changes in national needs for immunizations. The Affordable Care Act requires first dollar coverage of immunizations and other preventive care, allowing a reduction in federal funding for vaccine purchase and a reallocation of funds to other uses such as infrastructure development. In fiscal year 2013, Section 317 rules redefined the population eligible for immunization with Section 317 purchased vaccines. In Tennessee, the response was a policy change that redefined the population who would receive immunizations at health departments

The Effects of the State of Tennessee Immunization Policy Change of 2011 - 2012 on Vaccination Uptake in East Tennessee

In the United States, funding for the purchase of vaccines depend on annual Congressional allocations. These allocations fluctuate from year to year as Congress responds to changes in national needs for immunizations. The Affordable Care Act requires first dollar coverage of immunizations and other preventive care, allowing a reduction in federal funding for vaccine purchase and a reallocation of funds to other uses such as infrastructure development. In fiscal year 2012, the loss of funds allocated from the American Recovery and Reinvestment Act required action by states to ensure appropriate use of remaining funds. In Tennessee, the response was a policy change that redefined the population who would receive immunizations at health departments

Dynamic Localization in Quantum Wires

In the paper the dynamic localization of charged particle (electron) in a quantum wire under the external non-uniform time-dependent electric field is considered. The electrons are trapped in a deep 'dynamic' quantum wells which are the result of specific features of the potential imposed on 2D electron gas: the scale of spatial nonuniformity is much smaller then the electron mean free path (L_1 << \bar{l}) and the frequency is much greater then \tau^{-1}, where \tau is the electron free flight time. As a result, the effect of this field on the charged particle is in a sense equivalent to the effect of a time-independent effective potential, that is a sequence of deep 'dynamic' quantum wells were the elelctrons are confined. The possible consequeces of this effect are also discussed and similarity with the classical Paul traps are emphasized.Comment: 21 pages, 1 figur

A Case Study of Cross-Jurisdiction Resource Sharing: The Merger of Two Tuberculosis Clinics in East Tennessee.

Cross-jurisdiction resource sharing is considered a possible means to improve efficiency and effectiveness of public health service delivery. A merger of the Tuberculosis (TB) clinics of a rural and a metropolitan jurisdiction in East Tennessee provided an opportunity to study service provision changes in real time. A mixed methods approach was used, including quantitative data on latent TB treatment outcomes and qualitative data from staff interviews, as well as documentation of changes in staffing time in TB services. Results showed a mix of efficiency changes, indicating probable increased pressure on key service providers after the merger, in addition to expected improvements of economies of scale such as a reduction in overall staff time. Mechanisms found beneficial in coping with the merger, such as face-to-face meetings between coworkers and management of the different jurisdictions were identified at interview. The clinic merger was associated with a balance of efficiency changes, problems and advantages, and this balance is likely to change as new working arrangements become more routine

Use of intraventricular ribbon gauze to reduce particulate emboli during aortic valve replacement

BACKGROUND: The incidence of cerebrovascular accidents following aortic valve surgery remains a devastating complication. The aim of this study was to determine the number of potential embolic material arising during aortic valve replacement and to examine the efficacy of using ribbon gauze in the left ventricle during removal of the native valve and decalcification of the aortic annulus. METHODS: Ribbon gauze was inserted into the left ventricular cavity prior to aortic valve excision in an unselected, prospectively studied series of 30 patients undergoing aortic valve replacement. A further 30 lengths of ribbon gauze were soaked in the pericardiotomy blood of the same patients and all were subjected to histological analysis. RESULTS: The median number of tissue fragments from the aortic valve replacement group was significantly higher than in the control group 5 (0–18) versus 0 (0–1) (p = 3.6 × 10(-5)). The size of tissue fragments varied between 0.1 and 9.0 mm with a mean of 0.61 ± 1.12 mm and a median of 0.2 mm. There was a significantly higher number of tissue fragments associated with patients having surgery for aortic stenosis when compared with patients who had aortic regurgitation with median of 5 (0–18) versus 0 (0–3) (p = 0.8 × 10(-3)). CONCLUSION: Significant capture of particulate debris by the intraventricular ribbon gauze suggests that the technique of left ventricular ribbon gauze insertion during aortic valve excision has merit