Paving the way for patient centricity in real-world evidence (RWE): Qualitative interviews to identify considerations for wider implementation of patient-reported outcomes in RWE generation.

Objectives: Real-world evidence (RWE) generation can be enhanced by including patient-reported outcomes (PROs). Methods for collecting and using PRO data in the real-world setting are currently underdeveloped and there is no international guidance specific to its use in this context. This study explored stakeholders' perspectives and needs for using PROs in RWE generation. Barriers, facilitators, and opportunities for wider use of PROs in real-world studies were also investigated. Methods: Online semi-structured interviews were conducted with international stakeholders: patients, patient advocates, regulators, payers, clinicians, academic researchers, and industry experts. Interviews were recorded, transcribed verbatim and analysed using NVivo 20. Thematic analysis was conducted based on the updated Consolidated Framework for Implementation Research (CFIR). Results: Twenty-three interviews were conducted. Participants confirmed that the use of PROs in RWE generation is not yet well established. Participants expressed a mixed level of confidence in the value of PROs collected in a real-world setting. Operational challenges associated with collecting routine PRO data to inform care delivery at the individual level (e.g., setting up infrastructure) need to be addressed. Methodological and other challenges (e.g., financing research) associated with collecting prospective de novo data in a real-world setting should be considered to facilitate PRO utilisation in real-world studies. Conclusions: Several opportunities and challenges were identified regarding the broader use of PROs in RWE research. Joint efforts from different stakeholders are needed to maximise PRO implementation, with consideration given to each stakeholders' specific needs (e.g., by developing good practices).

Monitoring ADO dependent proteolysis in cells using fluorescent reporter proteins.

2-Aminoethanethiol dioxygenase (ADO) is the mammalian orthologue of the plant cysteine oxidases and together these enzymes are responsible for catalysing dioxygenation of N-terminal cysteine residues of certain proteins. This modification creates an N-degron motif that permits arginylation and subsequent proteasomal degradation of such proteins via the Arg-branch of the N-degron pathway. In humans 4 proteins have been identified as substrates of ADO; regulators of G-protein signalling (RGS) 4, 5 and 16, and interleukin-32 (IL-32). Nt-cysteine dioxygenation of these proteins occurs rapidly under normoxic conditions, but ADO activity is very sensitive to O2 availability and as such the stability of substrate proteins is inversely proportional to cellular O2 levels. Much is still to understand about the biochemistry and physiology of this pathway in vitro and in vivo, and Cys N-degron targeted fluorescent proteins can provide a simple and effective tool to study this at both subcellular and high-throughput scales. This chapter describes the design, production and implementation of a fluorescent fusion protein proteolytically regulated by ADO and the N-degron pathway.

Comparative analysis of N-terminal cysteine dioxygenation and prolyl-hydroxylation as oxygen-sensing pathways in mammalian cells.

In animals, adaptation to changes in cellular oxygen levels is coordinated largely by 2-oxoglutarate-dependent prolyl-hydroxylase domain (PHD) dioxygenase family members, which regulate the stability of their hypoxia-inducible factor (HIF) substrates to promote expression of genes that adapt cells to hypoxia. Recently, 2-aminoethanethiol dioxygenase (ADO) was identified as a novel O2-sensing enzyme in animals. Through N-terminal cysteine dioxygenation and the N-degron pathway, ADO regulates the stability of a set of non-transcription factor substrates; the regulators of G-protein signaling 4, 5. and 16 and interleukin-32. Here, we set out to compare and contrast the in cellulo characteristics of ADO and PHD enzymes in an attempt to better understand their co-evolution in animals. We find that ADO operates to regulate the stability of its substrates rapidly and with similar O2-sensitivity to the PHD/HIF pathway. ADO appeared less sensitive to iron chelating agents or transition metal exposure than the PHD enzymes, possibly due to tighter catalytic-site Fe2+ coordination. Unlike the PHD/HIF pathway, the ADO/N-degron pathway was not subject to feedback by hypoxic induction of ADO, and induction of ADO substrates was well sustained in response to prolonged hypoxia. The data also reveal strong interactions between proteolytic regulation of targets by ADO and transcriptional induction of those targets, that shape integrated cellular responses to hypoxia. Collectively, our comparative analysis provides further insight into ADO/N-degron-mediated oxygen sensing and its integration into established mechanisms of oxygen homeostasis.

Implementation of patient-reported outcome measures in real-world evidence studies: Analysis of ClinicalTrials.gov records (1999-2021).

BACKGROUND: Real-world evidence (RWE) plays an increasingly important role within global regulatory and reimbursement processes. RWE generation can be enhanced by collecting and using patient-reported outcomes (PROs), which can provide valuable information on the effectiveness, safety, and tolerability of health interventions from the patient perspective. This analysis aims to examine and summarise the utilisation of patient-reported outcomes measures (PROMs) in real-world studies. METHODS: Descriptions of phase IV trials were downloaded on July 22, 2021 from the Clinicaltrials.gov database since its inception. An automated algorithm was built to detect trials utilising PROMs and composite measures including patient-reported components. Search terms were developed based on the PROQOLID database. RESULTS: Of 27,976 phase IV clinical trials posted on Clinicaltrials.gov between 1999 and July 2021, 21% and 4% used PROMs and composite measures, respectively. Recent years demonstrated a steady increase in the utilisation of PROMs in phase IV trials. CONCLUSIONS: The use of PROMs in phase IV trials seems to be lower than its use in earlier phases of clinical research. Increased uptake of PROMs in RWE studies can be facilitated in a number of ways including the development of standards for their collection, analysis and use.

Systematic review of guidance for the collection and use of patient-reported outcomes in real-world evidence generation to support regulation, reimbursement and health policy.

BACKGROUND: Real-world evidence (RWE) plays an increasingly important role within global regulatory and reimbursement processes. RWE generation can be enhanced by the collection and use of patient-reported outcomes (PROs), which can provide valuable information on the effectiveness, safety, and tolerability of health interventions from the patient perspective. This systematic review aims to examine and summarise the available PRO-specific recommendations and guidance for RWE generation. METHODS AND FINDINGS: Medical Literature Analysis and Retrieval System Online, Excerpta Medica Database, and websites of selected organisations were systematically searched to identify relevant publications. 1,249 articles were screened of which 7 papers met the eligibility criteria and were included in the review. The included publications provided PRO-specific recommendations to facilitate the use of PROs for RWE generation and these were extracted and grouped into eight major categories. These included: (1) instrument selection, (2) participation and engagement, (3) burden to health care professionals and patients, (4) stakeholder collaboration, (5) education and training, (6) PRO implementation process, (7) data collection and management, and (8) data analysis and presentation of results. The main limitation of the study was the potential exclusion of relevant publications, due to poor indexing of the databases and websites searched. CONCLUSIONS: PROs may provide valuable and crucial patient input in RWE generation. Whilst valuable insights can be gained from guidance for use of PROs in clinical care, there is a lack of international guidance specific to RWE generation in the context of use for regulatory decision-making, reimbursement, and health policy. Clear and appropriate evidence-based guidance is required to maximise the potential benefits of implementing PROs for RWE generation. Unique aspects between PRO guidance for clinical care and other purposes should be differentiated. The needs of various stakeholder groups (including patients, health care professionals, regulators, payers, and industry) should be considered when developing future guidelines.

Nitric oxide biosensor uncovers diminished ferrous iron-dependency of cultured cells adapted to physiological oxygen levels.

Iron is an essential metal for cellular metabolism and signaling, but it has adverse effects in excess. The physiological consequences of iron deficiency are well established, yet the relationship between iron supplementation and pericellular oxygen levels in cultured cells and their downstream effects on metalloproteins has been less explored. This study exploits the metalloprotein geNOps in cultured HEK293T epithelial and EA.hy926 endothelial cells to test the iron-dependency in cells adapted to standard room air (18 kPa O2) or physiological normoxia (5 kPa O2). We show that cells in culture require iron supplementation to activate the metalloprotein geNOps and demonstrate for the first time that cells adapted to physiological normoxia require significantly lower iron compared to cells adapted to hyperoxia. This study establishes an essential role for recapitulating oxygen levels in vivo and uncovers a previously unrecognized requirement for ferrous iron supplementation under standard cell culture conditions to achieve geNOps functionality.

International perspectives on suboptimal patient-reported outcome trial design and reporting in cancer clinical trials: A qualitative study.

PURPOSE: Evidence suggests that the patient-reported outcome (PRO) content of cancer trial protocols is frequently inadequate and non-reporting of PRO findings is widespread. This qualitative study examined the factors influencing suboptimal PRO protocol content, implementation, and reporting, and use of PRO data during clinical interactions. METHODS: Semi-structured interviews were conducted with four stakeholder groups: (1) trialists and chief investigators; (2) people with lived experience of cancer; (3) international experts in PRO cancer trial design; (4) journal editors, funding panelists, and regulatory agencies. Data were analyzed using directed thematic analysis with an iterative coding frame. RESULTS: Forty-four interviews were undertaken. Several factors were identified that could influenced effective integration of PROs into trials and subsequent findings. Participants described (1) late inclusion of PROs in trial design; (2) PROs being considered a lower priority outcome compared to survival; (3) trialists' reluctance to collect or report PROs due to participant burden, missing data, and perceived reticence of journals to publish; (4) lack of staff training. Strategies to address these included training research personnel and improved communication with site staff and patients regarding the value of PROs. Examples of good practice were identified. CONCLUSION: Misconceptions relating to PRO methodology and its use may undermine their planning, collection, and reporting. There is a role for funding, regulatory, methodological, and journalistic institutions to address perceptions around the value of PROs, their position within the trial outcomes hierarchy, that PRO training and guidance is available, signposted, and readily accessible, with accompanying measures to ensure compliance with international best practice guidelines.

Hypoxic and pharmacological activation of HIF inhibits SARS-CoV-2 infection of lung epithelial cells.

COVID-19, caused by the novel coronavirus SARS-CoV-2, is a global health issue with more than 2 million fatalities to date. Viral replication is shaped by the cellular microenvironment, and one important factor to consider is oxygen tension, in which hypoxia inducible factor (HIF) regulates transcriptional responses to hypoxia. SARS-CoV-2 primarily infects cells of the respiratory tract, entering via its spike glycoprotein binding to angiotensin-converting enzyme 2 (ACE2). We demonstrate that hypoxia and the HIF prolyl hydroxylase inhibitor Roxadustat reduce ACE2 expression and inhibit SARS-CoV-2 entry and replication in lung epithelial cells via an HIF-1α-dependent pathway. Hypoxia and Roxadustat inhibit SARS-CoV-2 RNA replication, showing that post-entry steps in the viral life cycle are oxygen sensitive. This study highlights the importance of HIF signaling in regulating multiple aspects of SARS-CoV-2 infection and raises the potential use of HIF prolyl hydroxylase inhibitors in the prevention or treatment of COVID-19.

Development of a core outcome set for use in community-based bipolar trials-A qualitative study and modified Delphi.

BACKGROUND: A core outcome set (COS) is a standardised collection of outcomes to be collected and reported in all trials within a research area. A COS can reduce reporting bias and facilitate evidence synthesis. This is currently unavailable for use in community-based bipolar trials. This research aimed to develop such a COS, with input from a full range of stakeholders. METHODS: A co-production approach was used throughout. A longlist of outcomes was derived from focus groups with people with a bipolar diagnosis and carers, interviews with healthcare professionals and a rapid review of outcomes listed in bipolar trials on the Cochrane database. An expert panel with personal and/or professional experience of bipolar participated in a modified Delphi process and the COS was finalised at a consensus meeting. RESULTS: Fifty participants rated the importance of each outcome. Sixty-six outcomes were included in Round 1 of the questionnaire; 13 outcomes were added by Round 1 participants and were rated in Round 2. Seventy-six percent of participants (n = 38) returned to Round 2 and 60 outcomes, including 4 outcomes added by participants in Round 1, received a rating of 7-9 by >70% and 1-3 by <25% of the sample. Fourteen participants finalised a COS containing 11 outcomes at the consensus meeting: personal recovery; connectedness; clinical recovery of bipolar symptoms; mental health and wellbeing; physical health; self-monitoring and management; medication effects; quality of life; service outcomes; experience of care; and use of coercion. CONCLUSIONS: This COS is recommended for use in community-based bipolar trials to ensure stakeholder-relevant outcomes, facilitate data synthesis, and transparent reporting. The COS includes guidance notes for each outcome to allow the identification of suitable measurement instruments. Further validation is recommended for use with a wide range of communities and to achieve standardised measurement.

Nrf2-regulated redox signaling in brain endothelial cells adapted to physiological oxygen levels: Consequences for sulforaphane mediated protection against hypoxia-reoxygenation.

Ischemic stroke is associated with a surge in reactive oxygen species generation during reperfusion. The narrow therapeutic window for the delivery of intravenous thrombolysis and endovascular thrombectomy limits therapeutic options for patients. Thus, understanding the mechanisms regulating neurovascular redox defenses are key for improved clinical translation. Our previous studies in a rodent model of ischemic stroke established that activation of Nrf2 defense enzymes by pretreatment with sulforaphane (SFN) affords protection against neurovascular and neurological deficits. We here further investigate SFN mediated protection in mouse brain microvascular endothelial cells (bEnd.3) adapted long-term (5 days) to hyperoxic (18 kPa) and normoxic (5 kPa) O2 levels. Using an O2-sensitive phosphorescent nanoparticle probe, we measured an intracellular O2 level of 3.4 ± 0.1 kPa in bEnd 3 cells cultured under 5 kPa O2. Induction of HO-1 and GCLM by SFN (2.5 µM) was significantly attenuated in cells adapted to 5 kPa O2, despite nuclear accumulation of Nrf2. To simulate ischemic stroke, bEnd.3 cells were adapted to 18 or 5 kPa O2 and subjected to hypoxia (1 kPa O2, 1 h) and reoxygenation. In cells adapted to 18 kPa O2, reoxygenation induced free radical generation was abrogated by PEG-SOD and significantly attenuated by pretreatment with SFN (2.5 µM). Silencing Nrf2 transcription abrogated HO-1 and NQO1 induction and led to a significant increase in reoxygenation induced free radical generation. Notably, reoxygenation induced oxidative stress, assayed using the luminescence probe L-012 and fluorescence probes MitoSOX™ Red and FeRhoNox™-1, was diminished in cells cultured under 5 kPa O2, indicating an altered redox phenotype in brain microvascular cells adapted to physiological normoxia. As redox and other intracellular signaling pathways are critically affected by O2, the development of antioxidant therapies targeting the Keap1-Nrf2 defense pathway in treatment of ischemia-reperfusion injury in stroke, coronary and renal disease will require in vitro studies conducted under well-defined O2 levels.

CXCR2 antagonist for patients with chronic obstructive pulmonary disease with chronic mucus hypersecretion: a phase 2b trial.

BACKGROUND: Oral CXC chemokine receptor 2 (CXCR2) antagonists have been shown to inhibit neutrophil migration and activation in the lung in preclinical and human models of neutrophilic airway inflammation. A previous study with danirixin, a reversible CXCR2 antagonist, demonstrated a trend for improved respiratory symptoms and health status in patients with COPD. METHODS: This 26-week, randomised, double-blind, placebo-controlled phase IIb study enrolled symptomatic patients with mild-to-moderate COPD at risk for exacerbations. Patients received danirixin 5, 10, 25, 35 or 50 mg twice daily or placebo in addition to standard of care. Primary end-points were the dose response of danirixin compared with placebo on the incidence and severity of respiratory symptoms (Evaluating Respiratory Symptoms in COPD [E-RS:COPD] scores) and safety. Secondary end-points included the incidence of moderate-severe exacerbations, health status (COPD Assessment test, CAT) and health-related quality of life HRQoL (St. George Respiratory Questionnaire-COPD, SGRQ-C). RESULTS: A total of 614 participants were randomized to treatment. There were no improvements in E-RS:COPD, CAT or SGRQ-C scores in participants treated with any dose of danirixin compared to placebo; a larger than expected placebo effect was observed. There was an increased incidence of exacerbation in the danirixin-treated groups and an increased number of pneumonias in participants treated with danirixin 50 mg. CONCLUSIONS: The robust placebo and study effects prohibited any conclusions on the efficacy of danirixin. However, the absence of a clear efficacy benefit and the observed increase in exacerbations in danirixin-treated groups suggests an unfavorable benefit-risk profile in patients with COPD. TRIAL REGISTRATION: This study was registered with clinicaltrials.gov, NCT03034967.

Conserved N-terminal cysteine dioxygenases transduce responses to hypoxia in animals and plants.

Organisms must respond to hypoxia to preserve oxygen homeostasis. We identify a thiol oxidase, previously assigned as cysteamine (2-aminoethanethiol) dioxygenase (ADO), as a low oxygen affinity (high-K mO2) amino-terminal cysteine dioxygenase that transduces the oxygen-regulated stability of proteins by the N-degron pathway in human cells. ADO catalyzes the conversion of amino-terminal cysteine to cysteine sulfinic acid and is related to the plant cysteine oxidases that mediate responses to hypoxia by an identical posttranslational modification. We show in human cells that ADO regulates RGS4/5 (regulator of G protein signaling) N-degron substrates, modulates G protein-coupled calcium ion signals and mitogen-activated protein kinase activity, and that its activity extends to other N-cysteine proteins including the angiogenic cytokine interleukin-32. Identification of a conserved enzymatic oxygen sensor in multicellular eukaryotes opens routes to better understanding and therapeutic targeting of adaptive responses to hypoxia.

Systematic Evaluation of Patient-Reported Outcome Protocol Content and Reporting in Cancer Trials.

BACKGROUND: Patient-reported outcomes (PROs) are captured within cancer trials to help future patients and their clinicians make more informed treatment decisions. However, variability in standards of PRO trial design and reporting threaten the validity of these endpoints for application in clinical practice. METHODS: We systematically investigated a cohort of randomized controlled cancer trials that included a primary or secondary PRO. For each trial, an evaluation of protocol and reporting quality was undertaken using standard checklists. General patterns of reporting where also explored. RESULTS: Protocols (101 sourced, 44.3%) included a mean (SD) of 10 (4) of 33 (range = 2-19) PRO protocol checklist items. Recommended items frequently omitted included the rationale and objectives underpinning PRO collection and approaches to minimize/address missing PRO data. Of 160 trials with published results, 61 (38.1%, 95% confidence interval = 30.6% to 45.7%) failed to include their PRO findings in any publication (mean 6.43-year follow-up); these trials included 49 568 participants. Although two-thirds of included trials published PRO findings, reporting standards were often inadequate according to international guidelines (mean [SD] inclusion of 3 [3] of 14 [range = 0-11]) CONSORT PRO Extension checklist items). More than one-half of trials publishing PRO results in a secondary publication (12 of 22, 54.5%) took 4 or more years to do so following trial closure, with eight (36.4%) taking 5-8 years and one trial publishing after 14 years. CONCLUSIONS: PRO protocol content is frequently inadequate, and nonreporting of PRO findings is widespread, meaning patient-important information may not be available to benefit patients, clinicians, and regulators. Even where PRO data are published, there is often considerable delay and reporting quality is suboptimal. This study presents key recommendations to enhance the likelihood of successful delivery of PROs in the future.

Defining Physiological Normoxia for Improved Translation of Cell Physiology to Animal Models and Humans.

The extensive oxygen gradient between the air we breathe (Po2 ~21 kPa) and its ultimate distribution within mitochondria (as low as ~0.5-1 kPa) is testament to the efforts expended in limiting its inherent toxicity. It has long been recognized that cell culture undertaken under room air conditions falls short of replicating this protection in vitro. Despite this, difficulty in accurately determining the appropriate O2 levels in which to culture cells, coupled with a lack of the technology to replicate and maintain a physiological O2 environment in vitro, has hindered addressing this issue thus far. In this review, we aim to address the current understanding of tissue Po2 distribution in vivo and summarize the attempts made to replicate these conditions in vitro. The state-of-the-art techniques employed to accurately determine O2 levels, as well as the issues associated with reproducing physiological O2 levels in vitro, are also critically reviewed. We aim to provide the framework for researchers to undertake cell culture under O2 levels relevant to specific tissues and organs. We envisage that this review will facilitate a paradigm shift, enabling translation of findings under physiological conditions in vitro to disease pathology and the design of novel therapeutics.

Patient-reported outcome measures used in patients with primary sclerosing cholangitis: a systematic review.

BACKGROUND: Primary Sclerosing Cholangitis (PSC) is a rare chronic, cholestatic liver condition in which patients can experience a range of debilitating symptoms. Patient reported outcome measures (PROMs) could provide a valuable insight into the impact of PSC on patient quality of life and symptoms. A previous review has been conducted on the quality of life instruments used in liver transplant recipients. However, there has been no comprehensive review evaluating PROM use or measurement properties in PSC patients' to-date. The aim of the systematic review was to: (a) To identify and categorise which PROMs are currently being used in research involving the PSC population (b) To investigate the measurement properties of PROMs used in PSC. METHODS: A systematic review of Medline, EMBASE and CINAHL, from inception to February 2018, was undertaken. The methodological quality of included studies was assessed using the Consensus-based Standards for selection of health Measurement Instruments (COSMIN) checklist. RESULTS: Thirty-seven studies were identified, which included 36 different PROMs. Seven PROMs were generic, 10 disease-specific, 17 symptom-specific measures and 2 measures on dietary intake. The most common PROMs were the Short form-36 (SF-36) (n = 15) and Chronic liver disease questionnaire (CLDQ) (n = 6). Only three studies evaluated measurement properties, two studies evaluated the National Institute of Diabetes Digestive and Kidney Diseases Liver Transplant (NIDDK-QA) and one study evaluated the PSC PRO; however, according to the COSMIN guidelines, methodological quality was poor for the NIDDK-QA studies and fair for the PSC PRO study. CONCLUSION: A wide variety of PROMs have been used to assess health-related quality of life and symptom burden in patients with PSC; however only two measures (NIDDK-QA and PSC PRO) have been formally validated in this population. The newly developed PSC PRO requires further validation in PSC patients with diverse demographics, comorbidities and at different stages of disease; however this is a promising new measure with which to assess the impact of PSC on patient quality of life and symptoms.

Evaluation of patient-reported outcome protocol content and reporting in UK cancer clinical trials: the EPiC study qualitative protocol.

INTRODUCTION: Patient-reported outcomes (PROs) are increasingly included within cancer clinical trials. If appropriately collected, analysed and transparently reported, these data might provide invaluable evidence to inform patient care. However, there is mounting indication that the design and reporting of PRO data in cancer trials may be suboptimal. This programme of research will establish via three interlinked studies whether these findings are applicable to UK cancer trials, and if so, how to best enhance the way PROs are assessed, managed and reported in clinical trials. This study will explore with key stakeholders factors that influence optimal PRO protocol content, implementation and reporting and make recommendations for training and guidance. METHODS AND ANALYSIS: Semistructured interviews will be conducted with members of key stakeholder groups. The purposive sample of up to 48 participants will include: (1) trial chief investigators, trial management group members, statisticians and research nurses of cancer trials including primary or secondary PRO recruited via the National Cancer Research Institute (NCRI) Clinical Studies Group and Consumer Liaison Group and the UK Clinical Research Collaboration Registered UK Clinical Trial Unit Network; (2) NCRI Consumer Liaison Group members; (3) international experts in PRO oncology trial design; and (4) journal editors and funding bodies. Data will be analysed using directed thematic analysis employing a coding frame and modified as analysis progresses. Formal triangulation of coding and member checking will be employed to enhance credibility. ETHICS AND DISSEMINATION: This study was approved by the University of Birmingham Ethics Committee (Ref: ERN_17-0085). Findings will be disseminated via conference presentations, peer-reviewed journals, patient groups and social media (@CPROR_UoB; http://www.birmingham.ac.uk/cpror). PROSPERO REGISTRATION NUMBER: CRD42016036533.

Reduced SERCA activity underlies dysregulation of Ca2+ homeostasis under atmospheric O2 levels.

Unregulated increases in cellular Ca2+ homeostasis are a hallmark of pathophysiological conditions and a key trigger of cell death. Endothelial cells cultured under physiologic O2 conditions (5% O2) exhibit a reduced cytosolic Ca2+ response to stimulation. The mechanism for reduced plateau [Ca2+]i upon stimulation was due to increased sarco/endoplasmic reticulum Ca2+ ATPase (SERCA)-mediated reuptake rather than changes in Ca2+ influx capacity. Agonist-stimulated phosphorylation of the SERCA regulatory protein phospholamban was increased in cells cultured under 5% O2. Elevation of cytosolic and mitochondrial [Ca2+] and cell death after prolonged ionomycin treatment, as a model of Ca2+ overload, were lower when cells were cultured long-term under 5% compared with 18% O2. This protection was abolished by cotreatment with the SERCA inhibitor cyclopiazonic acid. Taken together, these results demonstrate that culturing cells under hyperoxic conditions reduces their ability to efficiently regulate [Ca2+]i, resulting in greater sensitivity to cytotoxic stimuli.-Keeley, T. P., Siow, R. C. M., Jacob, R., Mann, G. E. Reduced SERCA activity underlies dysregulation of Ca2+ homeostasis under atmospheric O2 levels.

A PP2A-mediated feedback mechanism controls Ca2+-dependent NO synthesis under physiological oxygen.

Intracellular O2 is a key regulator of NO signaling, yet most in vitro studies are conducted in atmospheric O2 levels, hyperoxic with respect to the physiologic milieu. We investigated NO signaling in endothelial cells cultured in physiologic (5%) O2 and stimulated with histamine or shear stress. Culture of cells in 5% O2 (>5 d) decreased histamine- but not shear stress-stimulated endothelial (e)NOS activity. Unlike cells adapted to a hypoxic environment (1% O2), those cultured in 5% O2 still mobilized sufficient Ca2+ to activate AMPK. Enhanced expression and membrane targeting of PP2A-C was observed in 5% O2, resulting in greater interaction with eNOS in response to histamine. Moreover, increased dephosphorylation of eNOS in 5% O2 was Ca2+-sensitive and reversed by okadaic acid or PP2A-C siRNA. The present findings establish that Ca2+ mobilization stimulates both NO synthesis and PP2A-mediated eNOS dephosphorylation, thus constituting a novel negative feedback mechanism regulating eNOS activity not present in response to shear stress. This, coupled with enhanced NO bioavailability, underpins differences in NO signaling induced by inflammatory and physiologic stimuli that are apparent only in physiologic O2 levels. Furthermore, an explicit delineation between physiologic normoxia and genuine hypoxia is defined here, with implications for our understanding of pathophysiological hypoxia.-Keeley, T. P., Siow, R. C. M., Jacob, R., Mann, G. E. A PP2A-mediated feedback mechanism controls Ca2+-dependent NO synthesis under physiological oxygen.

Assessing the impact of healthcare research: A systematic review of methodological frameworks.

BACKGROUND: Increasingly, researchers need to demonstrate the impact of their research to their sponsors, funders, and fellow academics. However, the most appropriate way of measuring the impact of healthcare research is subject to debate. We aimed to identify the existing methodological frameworks used to measure healthcare research impact and to summarise the common themes and metrics in an impact matrix. METHODS AND FINDINGS: Two independent investigators systematically searched the Medical Literature Analysis and Retrieval System Online (MEDLINE), the Excerpta Medica Database (EMBASE), the Cumulative Index to Nursing and Allied Health Literature (CINAHL+), the Health Management Information Consortium, and the Journal of Research Evaluation from inception until May 2017 for publications that presented a methodological framework for research impact. We then summarised the common concepts and themes across methodological frameworks and identified the metrics used to evaluate differing forms of impact. Twenty-four unique methodological frameworks were identified, addressing 5 broad categories of impact: (1) 'primary research-related impact', (2) 'influence on policy making', (3) 'health and health systems impact', (4) 'health-related and societal impact', and (5) 'broader economic impact'. These categories were subdivided into 16 common impact subgroups. Authors of the included publications proposed 80 different metrics aimed at measuring impact in these areas. The main limitation of the study was the potential exclusion of relevant articles, as a consequence of the poor indexing of the databases searched. CONCLUSIONS: The measurement of research impact is an essential exercise to help direct the allocation of limited research resources, to maximise research benefit, and to help minimise research waste. This review provides a collective summary of existing methodological frameworks for research impact, which funders may use to inform the measurement of research impact and researchers may use to inform study design decisions aimed at maximising the short-, medium-, and long-term impact of their research.