Margaret Banks

A self referencing platinum nanoparticle decorated enzyme-based microbiosensor for real time measurement of physiological glucose transport

Glucose is the central molecule in many biochemical pathways, and numerous approaches have been developed for fabricating micro biosensors designed to measure glucose concentration in/near cells and/or tissues. An inherent problem for microsensors used in physiological studies is a low signal-to-noise ratio, which is further complicated by concentration drift due to the metabolic activity of cells. A microsensor technique designed to filter extraneous electrical noise and provide direct quantification of active membrane transport is known as self-referencing. Self-referencing involves oscillation of a single microsensor via computer-controlled stepper motors within a stable gradient formed near cells/tissues (i.e., within the concentration boundary layer). The non-invasive technique provides direct measurement of trans-membrane (or trans-tissue) analyte flux. A glucose micro biosensor was fabricated using deposition of nanomaterials (platinum black, multiwalled carbon nanotubes, Nafion) and glucose oxidase on a platinum/iridium microelectrode. The highly sensitive/selective biosensor was used in the self-referencing modality for cell/tissue physiological transport studies. Detailed analysis of signal drift/noise filtering via phase sensitive detection (including a post-measurement analytical technique) are provided. Using this highly sensitive technique, physiological glucose uptake is demonstrated in a wide range of metabolic and pharmacological studies. Use of this technique is demonstrated for cancer cell physiology, bioenergetics, diabetes, and microbial biofilm physiology. This robust and versatile biosensor technique will provide much insight into biological transport in biomedical, environmental, and agricultural research applications.

Strengthening organizational performance through accreditation research-a framework for twelve interrelated studies: the ACCREDIT project study protocol

BackgroundService accreditation is a structured process of recognising and promoting performance and adherence to standards. Typically, accreditation agencies either receive standards from an authorized body or develop new and upgrade existing standards through research and expert views. They then apply standards, criteria and performance indicators, testing their effects, and monitoring compliance with them. The accreditation process has been widely adopted. The international investments in accreditation are considerable. However, reliable evidence of its efficiency or effectiveness in achieving organizational improvements is sparse and the value of accreditation in cost-benefit terms has yet to be demonstrated. Although some evidence suggests that accreditation promotes the improvement and standardization of care, there have been calls to strengthen its research base.In response, the ACCREDIT (A ccreditation C ollaborative for the C onduct of R esearch, E valuation and D esignated I nvestigations through T eamwork) project has been established to evaluate the effectiveness of Australian accreditation in achieving its goals. ACCREDIT is a partnership of key researchers, policymakers and agencies.FindingsWe present the framework for our studies in accreditation. Four specific aims of the ACCREDIT project, which will direct our findings, are to: (i) evaluate current accreditation processes; (ii) analyse the costs and benefits of accreditation; (iii) improve future accreditation via evidence; and (iv) develop and apply new standards of consumer involvement in accreditation. These will be addressed through 12 interrelated studies designed to examine specific issues identified as a high priority. Novel techniques, a mix of qualitative and quantitative methods, and randomized designs relevant for health-care research have been developed. These methods allow us to circumvent the fragmented and incommensurate findings that can be generated in small-scale, project-based studies. The overall approach for our research is a multi-level, multi-study design.DiscussionThe ACCREDIT project will examine the utility, reliability, relevance and cost effectiveness of differing forms of accreditation, focused on general practice, aged care and acute care settings in Australia. Empirically, there are potential research gains to be made by understanding accreditation and extending existing knowledge; theoretically, this design will facilitate a systems view of accreditation of benefit to the partnership, international research communities, and future accreditation designers.Accreditation of health-care organisations is a multimillion dollar industry which shapes care in many countries. Recent reviews of research show little evidence that accreditation increases safety or improves quality. Its time we knew about the cost and value of accreditation and about its future direction. [Professor John Øvretveit, Karolinska Institute, Sweden, 7 October 2009]

Non-Invasive Self-Referencing Electrochemical Sensors for Quantifying Real-Time Biofilm Analyte Flux

Current techniques for characterizing biofilm physiology lack the signal filtering capability required for quantifying signals associated with real time biologically active transport. Though a great deal was learned from previous investigations, no results have been reported on the characterization of in vivo, real time biofilm flux using non‐invasive (non‐destructive) techniques. This article introduces the self‐referencing technique for applications in biofilm physiology. Self‐referencing is a non‐invasive sensing modality which is capable of sensing changes in biologically active analyte flux as small as 10 fmolu2009cm−2u2009s−1. Studies directly characterizing flux, as opposed to concentration, have the advantage of quantifying real time changes in biologically active transport which are otherwise lost to background noise. The use of this modality for characterizing biofilm physiology is validated with a reversible enzyme inhibition study. The experiment used self‐referencing potentiometric sensors for quantifying real time ammonium and nitrite flux. Amperometric and optical sensing methods, though not presented herein, are also powerful sensing tools which benefit from operation in self‐referencing mode. Reversible ammonia monooxygenase inhibition by a copper chelator (thiourea), and subsequent relief by excess copper addition was successfully demonstrated using self‐referencing ion‐selective microelectrodes for a mature Nitrosomonas europaea biofilm. Biotechnol. Bioeng. 2009; 102: 791–799.

Membrane-Aerated Biofilm Proton and Oxygen Flux during Chemical Toxin Exposure

Bioreactors containing sessile bacteria (biofilms) grown on hollow fiber membranes have been used for treatment of many wastestreams. Real time operational control of bioreactor performance requires detailed knowledge of the relationship between bulk liquid water quality and physiological transport at the biofilm-liquid interface. Although large data sets exist describing membrane-aerated bioreactor effluent quality, very little real time data is available characterizing boundary layer transport under physiological conditions. A noninvasive, microsensor technique was used to quantify real time (≈1.5 s) changes in oxygen and proton flux for mature Nitrosomonas europaea and Pseudomonas aeruginosa biofilms in membrane-aerated bioreactors following exposure to environmental toxins. Stress response was characterized during exposure to toxins with known mode of action (chlorocarbonyl cyanide phenyl-hydrazone and potassium cyanide), and four environmental toxins (rotenone, 2,4-dinitrophenol, cadmium chloride, and pentachlorophenol). Exposure to sublethal concentrations of all environmental toxins caused significant increases in O(2) and/or H(+) flux (depending on the mode of action). These real time microscale signatures (i.e., fingerprints) of O(2) and H(+) flux can be coupled with bulk liquid analysis to improve our understanding of physiology in counter-diffusion biofilms found within membrane aerated bioreactors; leading to enhanced monitoring/modeling strategies for bioreactor control.

An empirical test of short notice surveys in two accreditation programmes.

OBJECTIVEnTo evaluate short notice surveys in accreditation programmes.nnnDESIGNnTwo trials using short notice surveys were conducted independently: a study of 20 healthcare organizations with the Australian Council on Healthcare Standards (ACHS) and a study of 7 general practices with the Australian General Practice Accreditation Limited (AGPAL). Participating organizations volunteered. ACHS and AGPAL selected 17 and 13 surveyors, respectively, and provided training for them on short notice surveys.nnnMETHODSnEach agencys short notice surveys were an abbreviated version of their current advanced notification surveys. Short notice surveys assessed accreditation programme criteria or indicators that corresponded to the Australian Commission on Safety and Quality in Health Cares priority issues. Fifteen (out of 45) ACHS criteria and 48 (out of 174) AGPAL indicators that aligned to the Commissions criteria were evaluated. Participating organizations were given 2 days notice prior to the short notice surveys. Ratings from the short notice surveys were compared with those from the most recent advanced notification surveys, and statistical tests were performed to detect differences and potential confounding factors. Surveyors and organizational staff completed a post-survey feedback questionnaire which was analysed thematically and by inferential statistics.nnnRESULTSnThe short notice survey approach overall produced ratings congruent with the advanced notification survey for both accreditation programmes. However, for both programmes short notice surveys assessed that more organizations would not reach the accreditation threshold as compared with the previous survey. Organizations in both programmes were judged to have achieved less successful performance against clinical standards by the short notice survey than the advanced notification survey. There was support from surveyors and organizational staff for short notice survey to be adopted. However, there were mixed views about the impact of short notice surveys and whether they validated trial participants continuous improvement efforts.nnnCONCLUSIONSnThe study demonstrated that short notice surveys are more critical in their assessment of clinical than administrative or corporate items. Short notice surveys, while broadly comparable with existing advanced notification survey practice, produced different accreditation outcomes for a significant proportion of the study organizations. The overall value and worth of short notice surveys remains to be proved.

Shear-induced detachment of biofilms from hollow fiber silicone membranes

A suite of techniques was utilized to evaluate the correlation between biofilm physiology, fluid‐induced shear stress, and detachment in hollow fiber membrane aerated bioreactors. Two monoculture species biofilms were grown on silicone fibers in a hollow fiber membrane aerated bioreactors (HfMBR) to assess detachment under laminar fluid flow conditions. Both physiology (biofilm thickness and roughness) and nutrient mass transport data indicated the presence of a steady state mature biofilm after 3 weeks of development. Surface shear stress proved to be an important parameter for predicting passive detachment for the two biofilms. The average shear stress at the surface of Nitrosomonas europaea biofilms (54.5u2009±u20093.2u2009mPa) was approximately 20% higher than for Pseudomonas aeruginosa biofilms (45.8u2009±u20097.7u2009mPa), resulting in higher biomass detachment. No significant difference in shear stress was measured between immature and mature biofilms of the same species. There was a significant difference in detached biomass for immature vs. mature biofilms in both species. However, there was no difference in detachment rate between the two species. Biotechnol. Bioeng. 2013; 110: 525–534.

An empirical test of accreditation patient journey surveys: randomized trial.

OBJECTIVEnTo evaluate the effectiveness of utilizing the patient journey survey (PJS) method in healthcare accreditation processes.nnnDESIGNnRandomized trial of the PJS method in parallel with the current accreditation survey (CAS) method of the Australian Council on Healthcare Standards (ACHS).nnnSETTINGnAcute healthcare organizations in Australia.nnnPARTICIPANTSnSeventeen organizations, 28 organizational staff, nine surveyors and 38 patients.nnnMAIN OUTCOME MEASURESnThe results of each surveying method were compared. Participants provided feedback, via 18 interviews and 40 questionnaire surveys, about the benefits and disadvantages of a PJS compared to a CAS.nnnRESULTSnThe PJS method is not as comprehensive as the CAS method for accreditation assessment. In matched assessments the majority of items were rated lower by the PJS method than by the CAS. PJSs were shown to be appropriate for assessing mandatory clinical criteria, but were less effective for assessing corporate and support criteria. The two methods diverged in their final assessments of which organizations met the accreditation threshold. Participants endorsed the use of PJSs within accreditation processes.nnnCONCLUSIONSnThe PJS methodology complements but is not a substitute for existing accreditation methods. There is significant stakeholder support for the inclusion of the PJS method within the current accreditation programme.

Analysing 'big picture' policy reform mechanisms : the Australian health service safety and quality accreditation scheme

Agencies promoting national health‐care accreditation reform to improve the quality of care and safety of patients are largely working without specific blueprints that can increase the likelihood of success.

Disseminating from the Centre to the Frontline: The Diffusion and Local Ownership of a National Health Policy Through the Use of Icons

Regulatory bodies continually confront the issue of how to diffuse health policies effectively, particularly those directed at changing frontline clinical practice. Knowing how to disseminate, embed and sustain improvements is a universal challenge. Being able to achieve ownership of policy at a local level, while ensuring a consistent national message, is a further complicating dimension. In this study we sought to answer the question: how can the Australian Commission on Safety and Quality in Health Care (ACSQHC) know the extent to which the National Safety and Quality Health Service (NSQHS) Standards information is disseminated to frontline clinicians? To do so, we conducted a unique study examining the diffusion of the NSQHS Standards, represented visually by icons, across the healthcare system. Using document analysis of two administrative databases, the study identified that by mid-2015 over 440 applications to use the icons had been received from healthcare organisations. Icons are being used for educational and clinical awareness raising purposes in diverse settings within organisations, across all states and territories. The representation of policy in the form of icons has allowed for ease of distribution, uptake, presentation, and recognition. The icons are an effective strategy for both the widespread diffusion and local ownership of a national health policy to those at the frontline of healthcare delivery.