Capivasertib combines with docetaxel to enhance anti-tumour activity through inhibition of AKT-mediated survival mechanisms in prostate cancer

BACKGROUND/OBJECTIVE

To explore the anti-tumour activity of combining AKT inhibition and docetaxel in PTEN protein null and WT prostate tumours.

METHODS

Mechanisms associated with docetaxel capivasertib treatment activity in prostate cancer were examined using a panel of in vivo tumour models and cell lines.

RESULTS

Combining docetaxel and capivasertib had increased activity in PTEN null and WT prostate tumour models in vivo. In vitro short-term docetaxel treatment caused cell cycle arrest in the majority of cells. However, a sub-population of docetaxel-persister cells did not undergo G2/M arrest but upregulated phosphorylation of PI3K/AKT pathway effectors GSK3β, p70S6K, 4E-BP1, but to a lesser extent AKT. In vivo acute docetaxel treatment induced p70S6K and 4E-BP1 phosphorylation. Treating PTEN null and WT docetaxel-persister cells with capivasertib reduced PI3K/AKT pathway activation and cell cycle progression. In vitro and in vivo it reduced proliferation and increased apoptosis or DNA damage though effects were more marked in PTEN null cells. Docetaxel-persister cells were partly reliant on GSK3β as a GSK3β inhibitor AZD2858 reversed capivasertib-induced apoptosis and DNA damage.

CONCLUSION

Capivasertib can enhance anti-tumour effects of docetaxel by targeting residual docetaxel-persister cells, independent of PTEN status, to induce apoptosis and DNA damage in part through GSK3β.

Genome-wide CRISPR screens identify the YAP/TEAD axis as a driver of persister cells in EGFR mutant lung cancer

Most lung cancer patients with metastatic cancer eventually relapse with drug-resistant disease following treatment and EGFR mutant lung cancer is no exception. Genome-wide CRISPR screens, to either knock out or overexpress all protein-coding genes in cancer cell lines, revealed the landscape of pathways that cause resistance to the EGFR inhibitors osimertinib or gefitinib in EGFR mutant lung cancer. Among the most recurrent resistance genes were those that regulate the Hippo pathway. Following osimertinib treatment a subpopulation of cancer cells are able to survive and over time develop stable resistance. These 'persister' cells can exploit non-genetic (transcriptional) programs that enable cancer cells to survive drug treatment. Using genetic and pharmacologic tools we identified Hippo signalling as an important non-genetic mechanism of cell survival following osimertinib treatment. Further, we show that combinatorial targeting of the Hippo pathway and EGFR is highly effective in EGFR mutant lung cancer cells and patient-derived organoids, suggesting a new therapeutic strategy for EGFR mutant lung cancer patients.

Clinical characteristics with inflammation profiling of long COVID and association with 1-year recovery following hospitalisation in the UK: a prospective observational study

BACKGROUND

No effective pharmacological or non-pharmacological interventions exist for patients with long COVID. We aimed to describe recovery 1 year after hospital discharge for COVID-19, identify factors associated with patient-perceived recovery, and identify potential therapeutic targets by describing the underlying inflammatory profiles of the previously described recovery clusters at 5 months after hospital discharge.

METHODS

The Post-hospitalisation COVID-19 study (PHOSP-COVID) is a prospective, longitudinal cohort study recruiting adults (aged ≥18 years) discharged from hospital with COVID-19 across the UK. Recovery was assessed using patient-reported outcome measures, physical performance, and organ function at 5 months and 1 year after hospital discharge, and stratified by both patient-perceived recovery and recovery cluster. Hierarchical logistic regression modelling was performed for patient-perceived recovery at 1 year. Cluster analysis was done using the clustering large applications k-medoids approach using clinical outcomes at 5 months. Inflammatory protein profiling was analysed from plasma at the 5-month visit. This study is registered on the ISRCTN Registry, ISRCTN10980107, and recruitment is ongoing.

FINDINGS

2320 participants discharged from hospital between March 7, 2020, and April 18, 2021, were assessed at 5 months after discharge and 807 (32·7%) participants completed both the 5-month and 1-year visits. 279 (35·6%) of these 807 patients were women and 505 (64·4%) were men, with a mean age of 58·7 (SD 12·5) years, and 224 (27·8%) had received invasive mechanical ventilation (WHO class 7-9). The proportion of patients reporting full recovery was unchanged between 5 months (501 [25·5%] of 1965) and 1 year (232 [28·9%] of 804). Factors associated with being less likely to report full recovery at 1 year were female sex (odds ratio 0·68 [95% CI 0·46-0·99]), obesity (0·50 [0·34-0·74]) and invasive mechanical ventilation (0·42 [0·23-0·76]). Cluster analysis (n=1636) corroborated the previously reported four clusters: very severe, severe, moderate with cognitive impairment, and mild, relating to the severity of physical health, mental health, and cognitive impairment at 5 months. We found increased inflammatory mediators of tissue damage and repair in both the very severe and the moderate with cognitive impairment clusters compared with the mild cluster, including IL-6 concentration, which was increased in both comparisons (n=626 participants). We found a substantial deficit in median EQ-5D-5L utility index from before COVID-19 (retrospective assessment; 0·88 [IQR 0·74-1·00]), at 5 months (0·74 [0·64-0·88]) to 1 year (0·75 [0·62-0·88]), with minimal improvements across all outcome measures at 1 year after discharge in the whole cohort and within each of the four clusters.

INTERPRETATION

The sequelae of a hospital admission with COVID-19 were substantial 1 year after discharge across a range of health domains, with the minority in our cohort feeling fully recovered. Patient-perceived health-related quality of life was reduced at 1 year compared with before hospital admission. Systematic inflammation and obesity are potential treatable traits that warrant further investigation in clinical trials.

FUNDING

UK Research and Innovation and National Institute for Health Research.

Abstract P066: Gain and loss of function genome-wide CRISPR screens identify Hippo signalling as an important driver of resistance in EGFR mutant lung cancer

Drug resistance is ultimately the cause of death for most cancer patients – even initially strong responses to treatment are usually followed by the emergence of resistance over time. This suggests the existence of residual or persistent cancer cells, creating a reservoir that ultimately gives rise to stable resistance. These drug tolerant persisters (‘the deadly survivors’) have been described for over a decade in numerous studies; they are often present as a minor fraction of the total tumour population and may exploit non-genetic (transcriptional) programs to allow the cells to survive drug treatment. 10-20% of lung adenocarcinoma patients harbour activating mutations in EGFR. Although treatment with the EGFR kinase inhibitor osimertinib has improved overall survival in such patients, almost all patients ultimately develop drug resistance. We carried out parallel genome-wide CRISPR gain and loss of function screens in EGFR mutant lung cancer cell lines treated with EGFR inhibitors, to identify the genes and pathways that may be important in enabling the survival of persister cells. We observed recurrent resistant genes in previously identified resistance pathways including PI3K (PTEN, TSC1, TSC2), MAPK (KRAS, NF1, MET), cell death (BCL2L11, BAX), the mediator complex (MED24, MED19) and ubiquitination (KCTD5, KEAP1). A secondary screen of 63 resistance genes that combined high content microscopy with CRISPR gene knockout demonstrated that 21% (13/63) of genes were associated with increased nuclear localisation of YAP1/WWTR1, key activators of the Hippo pathway. A closer review of the CRISPR screen data confirmed that many resistance hits are members of this pathway - upstream regulators (NF2, AMOTL2), core signalling genes (LATS1, LATS2), main effectors (WWTR1, YAP1), transcriptional co-effectors (TEAD3, FOSL1, VGLL4) and the SWI/SNF complex (ARID2, SMARCA4, SMARCB1, PBRM1). Hippo signalling is mediated through YAP1 and WWTR1 which bind to TEAD transcription factors and activate transcriptional programs affecting cell proliferation and apoptosis. We confirmed using CRISPR that knockout (NF2) or overexpression (YAP1, WWTR1) of key Hippo genes in the EGFR mutant lung cancer cell lines PC-9, HCC827 and HCC4006 resulted in up to 60-fold increased resistance to osimertinib and increased expression of canonical Hippo transcriptional targets. We therefore reasoned that the Hippo pathway might be involved in maintaining the survival of drug tolerant persister cells in this setting. Acute treatment of EGFR mutant cell lines with osimertinib was associated with increased nuclear localisation of YAP1 and WWTR1 and increased expression of canonical Hippo transcriptional targets. Furthermore, the combination of osimertinib and a TEAD inhibitor (K-975) almost completely abolished the survival of drug tolerant persister cells following treatment, indicating that this pathway is an important survival mechanism following drug treatment. Consequently, we propose Hippo signalling as an important target mechanism for the prevention of resistance to osimertinib.

Citation Format: Matthias Pfeifer, Jonathan Brammeld, Stacey Price, Matthew Martin, Hannah Thorpe, Aurelie Bornot, Ercia Banks, Nin Guan, Shanade Dunn, Maria Lisa Guerriero, Daniel O'Neill, James Pilling, Davide Gianni, James Brownell, Paul Smith, Ultan McDermott. Gain and loss of function genome-wide CRISPR screens identify Hippo signalling as an important driver of resistance in EGFR mutant lung cancer [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr P066.

Abstract 1100: Gain and loss of function genome-wide CRISPR screens identify Hippo signaling as an important driver of resistance in EGFR mutant lung cancer

10-20% of lung adenocarcinoma patients harbour activating mutations in EGFR. Although treatment with the EGFR kinase inhibitor osimertinib has improved overall survival in such patients, almost all patients ultimately develop drug resistance. In many cases the molecular resistance mechanisms remain unknown. A systematic identification of the involved genes and pathways is critical to overcome osimertinib resistance. To define the resistance landscape of EGFR kinase inhibition we performed genome-wide gain and loss of function CRISPR screens in EGFR mutant lung cancer cell lines treated with osimertinib. Resistance hits were enriched for genes in previously identified resistance pathways including PI3K (PTEN, TSC2), MAPK (NF1, MET), cell death (BCL2L11, BAX), the mediator complex (MED24, MED19) and ubiquitination (KCTD5, LZTR1). A secondary screen of 63 resistance genes that combined high content microscopy with CRISPR gene knockouts demonstrated that 21% (13/63) of genes were associated with increased nuclear localisation of YAP1/WWTR1, indicating transcriptional activation of the Hippo pathway. According to our screening data, many resistance hits mapped onto the Hippo signaling axis - upstream regulators (NF2, AMOTL2), core signaling genes (LATS1, LATS2), main effectors (WWTR1, YAP1), transcriptional co-effectors (TEAD3, FOSL1, VGLL4) and the SWI/SNF complex (ARID2, SMARCA4, SMARCB1, PBRM1). Hippo signaling is mediated through YAP1 and WWTR1 which bind to TEAD transcription factors and activate transcriptional programs affecting cell proliferation and apoptosis. We confirmed using CRISPR that knockout (NF2) or overexpression (YAP1, WWTR1) of key Hippo genes in the EGFR mutant lung cancer cell lines PC-9, HCC827 and HCC4006 resulted in up to 60-fold increased resistance to osimertinib and elevated activity of a TEAD reporter system, indicating activation of Hippo transcriptional programs. To maintain osimertinib resistance, expression of both YAP1 and WWTR1 was necessary, suggesting non-redundant roles for both Hippo main effectors in mediating osimertinib resistance. The combination of osimertinib and a TEAD inhibitor (MYF-01-37) reversed the resistance phenotype in NF2 KO cell line models in long-term proliferation assays and also substantially repressed the emergence of drug-tolerant persister cells in PC-9, HCC827 and HCC4006 cell lines following osimertinib treatment. These cells exhibited an enhanced apoptotic response when treated with combination of osimertinib and TEAD inhibitor. Consequently, we propose Hippo signaling as an important target mechanism for the prevention of resistance to osimertinib.

Citation Format: Matthias Pfeifer, Jonathan S. Brammeld, Stacey Price, Matthew Martin, Hannah Thorpe, Aurelie Bornot, Erica Banks, Nin Guan, Shanade Dunn, Maria Luisa Guerriero, Daniel O'Neill, James Pilling, Davide Gianni, James Brownell, Paul Smith, Ultan McDermott. Gain and loss of function genome-wide CRISPR screens identify Hippo signaling as an important driver of resistance in EGFR mutant lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1100.

Perspectives of hematology oncology clinicians about integrating palliative care in oncology

Patients with hematologic malignancies receive palliative care (pc) less frequently and later than patients with solid tumours. We compared survey responses of hematology oncology clinicians with other oncology clinicians to better understand their challenges with providing primary pc or using secondary pc. Patients' negative perceptions of pc and limited time or competing priorities were challenges for all clinicians. Compared with other oncology clinicians, more hematology oncology clinicians perceived pc referral criteria as too restrictive (40% vs. 22%, p = 0.021) and anticipated that integrating pc supports into their practice would require substantial change (53% vs. 28%, p = 0.014). This study highlights barriers that may need targeted interventions to better integrate pc into the care of patients with hematologic malignancies.

Author Correction: ARID1A influences HDAC1/BRD4 activity, intrinsic proliferative capacity and breast cancer treatment response

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

ARID1A influences HDAC1/BRD4 activity, intrinsic proliferative capacity and breast cancer treatment response

Using genome-wide clustered regularly interspaced short palindromic repeats (CRISPR) screens to understand endocrine drug resistance, we discovered ARID1A and other SWI/SNF complex components as the factors most critically required for response to two classes of estrogen receptor-alpha (ER) antagonists. In this context, SWI/SNF-specific gene deletion resulted in drug resistance. Unexpectedly, ARID1A was also the top candidate in regard to response to the bromodomain and extraterminal domain inhibitor JQ1, but in the opposite direction, with loss of ARID1A sensitizing breast cancer cells to bromodomain and extraterminal domain inhibition. We show that ARID1A is a repressor that binds chromatin at ER cis-regulatory elements. However, ARID1A elicits repressive activity in an enhancer-specific, but forkhead box A1-dependent and active, ER-independent manner. Deletion of ARID1A resulted in loss of histone deacetylase 1 binding, increased histone 4 lysine acetylation and subsequent BRD4-driven transcription and growth. ARID1A mutations are more frequent in treatment-resistant disease, and our findings provide mechanistic insight into this process while revealing rational treatment strategies for these patients.

Abstract 321: Genome-wide CRISPR screens identify combination strategies for Capivasertib (AZD5363; AKT) and AZD8186 (PI3Kβ/δ) in PTEN-null breast cancer

The PI3K-AKT-mTOR pathway is frequently hyper-activated in breast cancer and several inhibitors targeting the PI3K pathway, including AKT (Capivasertib; AZD5363) and PI3Kβ/δ (AZD8186), are currently in clinical development (phase I/II) targeting tumours with mutational activation of the pathway including those with loss of PTEN. A better understanding of the mechanisms of resistance/sensitization to Capivasertib and AZD8186 in PTEN-null breast cancer is critical to fully exploit the anti-tumour activity of these compounds and to develop combination strategies for more effective therapy. Here we performed genome-wide CRISPR-Cas9 knockout screens to identify genes that when targeted promote resistance (gRNA enrichment) or sensitivity (gRNA depletion) to Capivasertib and AZD8186 in three PTEN-null breast cancer cell lines. Our screens identified five genes (NPRL2, DEPDC5, DDIT4, HNRNPD and ZC3H4) whose inactivation promoted resistance to Capivasertib; two resistance genes (PIK3R2 and INPPL1) for AZD8186 and three resistance genes (TSC2, TSC1 and FIBP) for both compounds across all three cell lines. While this result strongly suggests that mTOR pathway reactivation is the major resistance mechanism, we also identified novel resistance genes such as FIBP. Our screens also identified a number of genes that when inactivated sensitize cells to Capivasertib and AZD8186 treatment. Eighteen of these sensitizers have inhibitors in clinical development and we have performed a combination screen to identify compounds that give the best synergy with Capivasertib/AZD8186. The most striking combination effect was detected with the Mcl-1 inhibitor, AZD5991. Mechanistic work is ongoing and our data suggest that Capivasertib/AZD8186 prime cells for apoptosis by a previously undescribed mechanism and combined inhibition with AZD5991 drives a rapid apoptotic response. Importantly, the combination with AZD5991 remains effective in breast cancer cells with acquired resistance to Capivasertib/AZD8186. These combinations showed synergistic tumour suppressive effect in a PTEN-null TNBC breast cancer xenograft model (AZD5991 + AZD8186/Capivasertib) and activity in a patient-derived xenograft model (AZD5991 + Capivasertib). Overall, our CRISPR screening data provide new insights into the genes and pathways that drive resistance to inhibitors of the PI3K pathway in PTEN-null breast cancer and have identified novel synergistic combinations to maximize therapeutic response.

Citation Format: Shanade Dunn, Jason Yu, Albert Gris-Oliver, James Pilling, Philip Hopcroft, Urs Yelland, Natalie Cureton, Anna Staniszewsla, Yan Zi Au, Swee Hoe Ong, Beverley Isherwood, Violeta Serra, Simon Barry, Barry R. Davies, James T. Lynch, Kosuke Yusa. Genome-wide CRISPR screens identify combination strategies for Capivasertib (AZD5363; AKT) and AZD8186 (PI3Kβ/δ) in PTEN-null breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 321.

Pediatric sacral nerve stimulator explanation due to complications or cure: a survival analysis

INTRODUCTION

Historically, there have been few treatment options for children with severe refractory bladder and bowel dysfunction (BBD). Sacral neuromodulation (SNM) continues to show promising results in this challenging pediatric population with recalcitrant lower urinary tract symptoms. At the authors institution, they have begun offering explantation to those with persistent improvement after >6 months of having device turned off. The authors hypothesized that (1) SNM explantation for cure increases with extended follow-up and (2) those explanted for cure would have improved symptoms and quality of life when compared to those explanted for complication.

MATERIALS & METHODS

The authors retrospectively reviewed all consecutive patients aged <18 years who underwent SNM placements at their institution (2012-2017). They excluded those without the second stage procedure. Reasons for device explantation were categorized as cure (resolution of symptoms with the device turned off for at least 6 months) or a complication (e.g. infection, need for magnetic resonance imaging, or pain). Non-parametric tests and survival analysis were used for analysis to account for differential follow-up time. Of those explanted, surveys were electronically sent to assess BBD severity and overall quality of life.

RESULTS

Of 67 children who underwent a first stage procedure, 62 (92.5%) underwent a second stage procedure. 61 met inclusion criteria (68.9% female, 29.5% with previous filum section, median age at implantation 10.3 years). During follow-up (median 2.3 years), 12 patients (19.7%) had the SNM exchanged/revised because of lead fracture/breakage and return of urinary symptoms. To date, 50 patients remain with their SNM implanted, and 11 have been explanted. Adjusting for follow-up time, the risk of explantation was 6.5% at 2 years (2.2% for cure, 4.3% for complications) (Figure 1). Explantation increased to 24.5% at 3 years (16.5% for cure, 8.0% for complications) and 40.4% at 4 years (32.4% for cure, 8.0% for complications). Questionnaires were collected on patients after explant (median 2.2 years), with improvement in those explanted for cure compared to complication (Figure 2).

DISCUSSION

Sacral neuromodulation explantation for cure is a novel concept previously not described in the literature. Limitations of this study include the relatively small numbers and lack of objective data in the cohort that remains with SNM device implanted.

CONCLUSION

Sacral neuromodulation is a safe, viable option for the pediatric patient with refractory bladder dysfunction. Furthermore, SNM explantation for cure is an option with increasing likelihood after 2 years.

Mortality of civilian patients with suspected traumatic haemorrhage receiving pre-hospital transfusion of packed red blood cells compared to pre-hospital crystalloid

Background

Major haemorrhage is a leading cause of mortality following major trauma. Increasingly, Helicopter Emergency Medical Services (HEMS) in the United Kingdom provide pre-hospital transfusion with blood products, although the evidence to support this is equivocal. This study compares mortality for patients with suspected traumatic haemorrhage transfused with pre-hospital packed red blood cells (PRBC) compared to crystalloid.

Methods

A single centre retrospective observational cohort study between 1 January 2010 and 1 February 2015. Patients triggering a pre-hospital Code Red activation were eligible. The primary outcome measure was all-cause mortality at 6 hours (h) and 28 days (d), including a sub-analysis of patients receiving a major and massive transfusion. Multivariable regression models predicted mortality. Multiple Imputation was employed, and logistic regression models were constructed for all imputed datasets.

Results

The crystalloid (n = 103) and PRBC (n = 92) group were comparable for demographics, Injury Severity Score (p = 0.67) and mechanism of injury (p = 0.73). Observed 6 h mortality was smaller in the PRBC group (n = 10, 10%) compared to crystalloid group (n = 19, 18%). Adjusted OR was not statistically significant (OR 0.48, CI 0.19–1.19, p = 0.11). Observed mortality at 28 days was smaller in the PRBC group (n = 21, 26%) compared to crystalloid group (n = 31, 40%), p = 0.09. Adjusted OR was not statistically significant (OR 0.66, CI 0.32–1.35, p = 0.26). A statistically significant greater proportion of the crystalloid group required a major transfusion (n = 62, 60%) compared to the PRBC group (n = 41, 40%), p = 0.02. For patients requiring a massive transfusion observed mortality was smaller in the PRBC group at 28 days (p = 0.07).

Conclusion

In a single centre UK HEMS study, in patients with suspected traumatic haemorrhage who received a PRBC transfusion there was an observed, but non-significant, reduction in mortality at 6 h and 28 days, also reflected in a massive transfusion subgroup. Patients receiving pre-hospital PRBC were significantly less likely to require an in-hospital major transfusion. Further adequately powered multi-centre prospective research is required to establish the optimum strategy for pre-hospital volume replacement in patients with traumatic haemorrhage.

Lay health educators within primary care practices to improve cancer screening uptake for South Asian patients: challenges in quality improvement

BACKGROUND

Cancer screening uptake is known to be low among South Asian residents of Ontario. The objective of this pilot study was to determine if lay health educators embedded within the practices of primary care providers could improve willingness to screen and cancer screening uptake for South Asian patients taking a quality improvement approach.

MATERIALS AND METHODS

Participating physicians selected quality improvement initiatives to use within their offices that they felt could increase willingness to screen and cancer screening uptake. They implemented initiatives, adapting as necessary, for six months.

RESULTS

Four primary care physicians participated in the study. All approximated that at least 60% of their patients were of South Asian ethnicity. All physicians chose to work with a preexisting lay health educator program geared toward South Asians. Health ambassadors spoke to patients in the office and telephoned patients. For all physicians, ~60% of South Asian patients who were overdue for cancer screening and who spoke directly to health ambassadors stated they were willing to be screened. One physician was able to track actual screening among contacted patients and found that screening uptake was relatively high: from 29.2% (colorectal cancer) to 44.6% (breast cancer) of patients came in for screening within six months of the first phone calls. Although physicians viewed the health ambassadors positively, they found the study to be time intensive and resource intensive, especially as this work was additional to usual clinical duties.

DISCUSSION

Using South Asian lay health educators embedded within primary care practices to telephone patients in their own languages showed promise in this study to increase awareness about willingness to screen and cancer screening uptake, but it was also time intensive and resource intensive with numerous challenges. Future quality improvement efforts should further develop the phone call invitation process, as well as explore how to provide infrastructure for lay health educator training and time.

Perovskite BiFeO3 thin film photocathode performance with visible light activity

Perovskite materials are now an important class of materials in the application areas of photovoltaics and photocatalysis. Inorganic perovskites such as BiFeO3 (BFO) are promising photocatalyst materials with visible light activity and inherent stability. Here we report the large area sol-gel synthesis of BFO films for solar stimulated water photo oxidation. By modifying the sol-gel synthesis process we have produced a perovskite material that has p-type behaviour and a flat band potential of ∼1.15 V (versus NHE). The photocathode produces a density of -0.004 mA cm(-2) at 0 V versus NHE under AM1.5 G illumination. We further show that 0.6 μmol h(-1) of O2 was produced at an external bias of -0.5 V versus Ag/AgCl. The addition of a non-percolating conducting network of Ag increases the photocurrent to -0.07 mA cm(-2) at 0 V versus NHE (at 2% Ag loading) with an increase to 2.7 μmol h(-1) for O2 production. We attribute the enhancement in photoelectrochemical performance to increased light absorption due light scattering by the incorporated Ag particles, improved charge transfer kinetics at the Ag/BFO interface and reduced over potential losses. We support these claims by an observed shift in flat band and onset potentials after Ag modification through UV-vis spectroscopy, Mott-Schottky plots and j-v curve analysis.

Shared decision making for infants born at the threshold of viability: a prognosis-based guideline

OBJECTIVE

Making prenatal decisions regarding resuscitation of extremely premature infants, based on gestational age alone is inadequate. We developed a prognosis-based guideline.

STUDY DESIGN

We followed a five step approach and used the AGREE II framework: (1) systematic review and critical appraisal of published guidelines; (2) identification of key medical factors for decision making; (3) systematic reviews; (4) creation of a multi-disciplinary working group and (5) external consultation and appraisal.

RESULT

No published guideline met high-quality appraisal criteria. Survival, neurodevelopmental disability, quality of life of child and parents, and maternal mortality and risk of long-term morbidity were identified as key for quality decision-making. Eighteen stakeholders (including parents) advocated for the incorporation of parents' values and preferences in the process.

CONCLUSION

A novel framework, based on prognosis, was generated to guide when early intensive and palliative care may both be offered to expectant parents. Pre-implementation assessment is underway to identify barriers and facilitators to putting in practice.

Primary care physicians' perceptions about and confidence in deciding which patients to refer for total joint arthroplasty of the hip and knee

OBJECTIVE

The purpose of this study is to examine the perceptions of primary care physicians (PCPs) regarding indications, contraindications, risks and benefits of total joint arthroplasty (TJA) and their confidence in selecting patients for referral for TJA.

DESIGN

PCPs recruited from among those providing care to participants in an established community cohort with hip or knee osteoarthritis (OA). Self-completed questionnaires were used to collect demographic and practice characteristics and perceptions about TJA. Confidence in referring appropriate patients for TJA was measured on a scale from 1 to 10; respondents scoring in the lowest tertile were considered to have 'low confidence'. Descriptive analyses were conducted and multiple logistic regression was used to determine key predictors of low confidence.

RESULTS

212 PCPs participated (58% response rate) (65% aged 50+ years, 45% female, 77% >15 years of practice). Perceptions about TJA were highly variable but on average, PCPs perceived that a typical surgical candidate would have moderate pain and disability, identified few absolute contraindications to TJA, and overestimated both the effectiveness and risks of TJA. On average, PCPs indicated moderate confidence in deciding who to refer. Independent predictors of low confidence were female physicians (OR = 2.18, 95% confidence interval (CI): 1.06-4.46) and reporting a 'lack of clarity about surgical indications' (OR = 3.54, 95% CI: 1.87-6.66).

CONCLUSIONS

Variability in perceptions and lack of clarity about surgical indications underscore the need for decision support tools to inform PCP - patient decision making regarding referral for TJA.

Plasmon enhanced visible light photocatalysis for TiO2 supported Pd nanoparticles

A photocatalyst consisting of nanostructured Pd photochemically deposited on 20 nm TiO2 displays a reaction half-life for rhodamine b decolourisation of 0.5 minute compared to the 9.4 minutes for unmodified P25 under identical reaction conditions. We associate this increased decolourisation rate to the increase in solar light harvesting which we have measured at 8% due to a significant red shift in the absorption profile of the catalyst. We relate the increased absorption of light with a visible active plasmon effect that is associated with the Pd nanostructures on the TiO2. This overall red-shift in the light harvesting for the catalyst leads to photocatalytic activity for excitations up to 600 nm.

Reduction of noise in the neonatal intensive care unit using sound-activated noise meters

OBJECTIVES

To determine if sound-activated noise meters providing direct audit and visual feedback can reduce sound levels in a level 3 neonatal intensive care unit (NICU).

DESIGN/METHODS

Sound levels (in dB) were compared between a 2-month period with noise meters present but without visual signal fluctuation and a subsequent 2 months with the noise meters providing direct audit and visual feedback.

RESULTS

There was a significant increase in the percentage of time the sound level in the NICU was below 50 dB across all patient care areas (9.9%, 8.9% and 7.3%). This improvement was not observed in the desk area where there are no admitted patients. There was no change in the percentage of time the NICU was below 45 or 55 dB.

CONCLUSIONS

Sound-activated noise meters seem effective in reducing sound levels in patient care areas. Conversations may have moved to non-patient care areas preventing a similar change there.

Examining the effects of a targeted noise reduction program in a neonatal intensive care unit

OBJECTIVES

To determine whether implementation of a noise reduction policy followed by the addition of direct audit and feedback reduces noise levels in a tertiary-level neonatal intensive care unit (NICU).

STUDY DESIGN

Noise level data was collected in three phases: (1) baseline (preintervention), (2) immediately postimplementation of our noise reduction policy, (3) postunveiling of direct audit and feedback mechanism.

SETTING

A level 3 NICU in Ontario, Canada.

INTERVENTIONS

Noise reduction policy and a direct audit and feedback mechanism.

MAIN OUTCOME MEASURES

Average noise level.

RESULTS

The baseline level of noise in our unit consistently exceeds guidelines with an average baseline noise of 49 dB (±1.4). Our intervention resulted in a significant reduction in noise levels for one of the four areas in our NICU [-1.06 dB (-1.52, -0.6)], with a trend towards reduction in a second area (-0.21 dB (-0.6, 0.18)). Unexpectedly, two other areas experienced a significant increase in noise (2.05 dB (1.18, 2.94); 0.85 dB (0.11, 1.59)).

CONCLUSIONS

The baseline noise in the NICU consistently exceeds guidelines, but reductions in noise levels are achievable. Nonetheless, more work is needed to find the optimal NICU design and noise reduction strategy.

Effluent Storage and Biomat Occurrence among Septic System Absorption Field Architectures in a Typic Fragiudult

On-site wastewater treatment systems (OWTSs) are commonly used by households in areas of low population density to treat household wastewater and recycle it back to the environment. However, new absorption field products of differing architecture types have recently become available. A 3-yr field study was conducted in Bethel Heights, northwest Arkansas to assess several newer architecture types (i.e., chambers, polystyrene-aggregate, and gravel-less pipe) relative to the traditional pipe-and-gravel design under wet- and dry-soil conditions. Thirteen products of four different architecture types were installed in 46-cm-deep trenches in a Captina silt loam (fine-silty, siliceous, active, mesic Typic Fragiudult). Products were evaluated based on in-trench solution storage measured with an electronic water-level sensor approximately weekly from January 2009 through January 2012. Between May 2010 and January 2012, the thickness of any biomat formation was measured approximately weekly by insertion of a wooden dowel through in-trench monitoring ports. Architecture type alone did not affect ( > 0.05) in-trench solution storage. However, solution storage among individual products differed under wet- and dry-soil conditions ( < 0.05). When present, biomat thickness differed significantly ( < 0.05) among all four architecture types, ranging from 1.4 to 6.2 cm thick on average in the pipe-and-aggregate and polystyrene-aggregate types, respectively. Regression analyses showed that biomat thickness increased in three products, did not change in nine products, and decreased in one product over time. Results showed that several currently approved alternative products had similar in-trench solution storage but that several alternative products also had greater solution storage than that of the traditional pipe-and-gravel system. With no observed effluent surfacing, the soil morphology approach appears to be adequate and appropriately environmentally conservative for assigning typical single-family loading rates to alternative OWTS products and to the traditional pipe-and-gravel system.

Non-ST-elevation myocardial infarction following foam ultrasound-guided sclerotherapy

The objective of the study was to describe a very rare complication of foam ultrasound-guided sclerotherapy (FUGS). An unusual case of persisting chest discomfort following FUGS in a 61-year-old woman led to a diagnosis of non-ST-elevation myocardial infarction. The patient was found to have a patent foramen ovale (PFO). The differential diagnoses of paradoxical embolism, gas embolism or vasospasm are discussed, with reference to relevant literature. A hypothesis of post sclerotherapy release of endothelin-1 (in a patient with a known PFO) leading to sustained coronary artery spasm causing sufficient myocardial damage to be reflected in elevated troponin levels is suggested.

Any episode of chest tightness or pain following FUGS should be considered as possibly cardiac in origin. Sustained symptoms warrant admission to hospital for troponin monitoring and ECG assessment.

2008 Niday Perinatal Database quality audit: report of a quality assurance project

INTRODUCTION

This quality assurance project was designed to determine the reliability, completeness and comprehensiveness of the data entered into Niday Perinatal Database.

METHODS

Quality of the data was measured by comparing data re-abstracted from the patient record to the original data entered into the Niday Perinatal Database. A representative sample of hospitals in Ontario was selected and a random sample of 100 linked mother and newborn charts were audited for each site. A subset of 33 variables (representing 96 data fields) from the Niday dataset was chosen for re-abstraction.

RESULTS

Of the data fields for which Cohen's kappa statistic or intraclass correlation coefficient (ICC) was calculated, 44% showed substantial or almost perfect agreement (beyond chance). However, about 17% showed less than 95% agreement and a kappa or ICC value of less than 60% indicating only slight, fair or moderate agreement (beyond chance).

DISCUSSION

Recommendations to improve the quality of these data fields are presented.