Hydration and nutrition care practices in stroke: findings from the UK and Australia

BACKGROUND

Dehydration and malnutrition are common in hospitalised patients following stroke leading to poor outcomes including increased mortality. Little is known about hydration and nutrition care practices in hospital to avoid dehydration or malnutrition, and how these practices vary in different countries. This study sought to capture how the hydration and nutrition needs of patients' post-stroke are assessed and managed in the United Kingdom (UK) and Australia (AUS).

AIM

To examine and compare current in-hospital hydration and nutrition care practice for patients with stroke in the UK and Australia.

METHODS

A cross-sectional survey was conducted between April and November 2019. Questionnaires were mailed to stroke specialist nurses in UK and Australian hospitals providing post-stroke inpatient acute care or rehabilitation. Non-respondents were contacted up to five times.

RESULTS

We received 150/174 (86%) completed surveys from hospitals in the UK, and 120/162 (74%) in Australia. Of the 270 responding hospitals, 96% reported undertaking assessment of hydration status during an admission, with nurses most likely to complete assessments (85%). The most common methods of admission assessment were visual assessment of the patient (UK 62%; AUS 58%), weight (UK 52%; AUS 52%), and body mass index (UK 47%; AUS 42%). Almost all (99%) sites reported that nutrition status was assessed at some point during admission, and these were mainly completed by nurses (91%). Use of standardised nutrition screening tools were more common in the UK (91%) than Australia (60%). Similar proportions of hydration management decisions were made by physicians (UK 84%; AUS 83%), and nutrition management decisions by dietitians (UK 98%; AUS 97%).

CONCLUSION

Despite broadly similar hydration and nutrition care practices after stroke in the UK and Australia, some variability was identified. Although nutrition assessment was more often informed by structured screening tools, the routine assessment of hydration was generally not. Nurses were responsible for assessment and monitoring, while dietitians and physicians undertook decision-making regarding management. Hydration care could be improved through the development of standardised assessment tools. This study highlights the need for increased implementation and use of evidence-based protocols in stroke hydration and nutrition care to improve patient outcomes.

Healthcare professionals' perspectives of the provision of, and challenges for, eating, drinking and psychological support post stroke: findings from semistructured interviews across India

AIM

This qualitative study explores with health professionals the provision of, and challenges for, postdischarge stroke care, focussing on eating, drinking and psychological support across India.

DESIGN

Qualitative semistructured interviews.

SETTING

Seven geographically diverse hospitals taking part in a Global Health Research Programme on Improving Stroke Care in India.

PARTICIPANTS

A purposive sample of healthcare professionals with current experience of working with patients who had a stroke.

RESULTS

Interviews with 66 healthcare professionals (23 nurses (14 staff nurses; 7 senior nurse officers; 1 intensive care unit nurse; 1 palliative care nurse)); 16 doctors (10 neurologists; 6 physicians); 10 physiotherapists; 5 speech and language therapists; 4 occupational therapists; 4 dieticians; 2 psychiatrists; and 2 social workers resulted in three main themes: integrated inpatient discharge care planning processes; postdischarge patient and caregiver role and challenges; patient and caregiver engagement post discharge.

CONCLUSIONS

Discharge planning was integrated and customised, although resources were limited in some sites. Task shifting compensated for a lack of specialists but was limited by staff education and training. Caregivers faced challenges in accessing and providing postdischarge care. Postdischarge care was mainly hospital based, supported by teleservices, especially for rural populations. Further research is needed to understand postdischarge care provision and the needs of stroke survivors and their caregivers.

Erratum: Next-to-Leading-Order QCD Corrections to Higgs Boson Plus Jet Production with Full Top-Quark Mass Dependence [Phys. Rev. Lett. 120, 162001 (2018)]

This corrects the article DOI: 10.1103/PhysRevLett.120.162001.

Stroke in India: A systematic review of the incidence, prevalence, and case fatality

BACKGROUND

The burden of stroke is increasing in India; stroke is now the fourth leading cause of death and the fifth leading cause of disability. Previous research suggests that the incidence of stroke in India ranges between 105 and 152/100,000 people per year. However, there is a paucity of available data and a lack of uniform methods across published studies.

AIM

To identify high-quality prospective studies reporting the epidemiology of stroke in India.

SUMMARY OF REVIEW

A search strategy was modified from the Cochrane Stroke Strategy and adapted for a range of bibliographic databases from January 1997 to August 2020. From 7717 identified records, nine studies were selected for inclusion; three population-based registries, a further three population-based registries also using community-based ascertainment and three community-based door-to-door surveys. Studies represented the four cities of Mumbai, Trivandrum, Ludhiana, Kolkata, the state of Punjab, and 12 villages of Baruipur in the state of West Bengal. The total population denominator was 22,479,509 and 11,654 (mean 1294 SD 1710) people were identified with incident stroke. Crude incidence of stroke ranged from 108 to 172/100,000 people per year, crude prevalence from 26 to 757/100,000 people per year, and one-month case fatality rates from 18% to 42%.

CONCLUSIONS

Further high-quality evidence is needed across India to guide stroke policy and inform the development and organization of stroke services. Future researchers should consider the World Health Organization STEPwise approach to Surveillance framework, including longitudinal data collection, the inclusion of census population data, and a combination of hospital-registry and comprehensive community ascertainment strategies to ensure complete stroke identification.

Progress towards an OECD reporting framework for transcriptomics and metabolomics in regulatory toxicology

Omics methodologies are widely used in toxicological research to understand modes and mechanisms of toxicity. Increasingly, these methodologies are being applied to questions of regulatory interest such as molecular point-of-departure derivation and chemical grouping/read-across. Despite its value, widespread regulatory acceptance of omics data has not yet occurred. Barriers to the routine application of omics data in regulatory decision making have been: 1) lack of transparency for data processing methods used to convert raw data into an interpretable list of observations; and 2) lack of standardization in reporting to ensure that omics data, associated metadata and the methodologies used to generate results are available for review by stakeholders, including regulators. Thus, in 2017, the Organisation for Economic Co-operation and Development (OECD) Extended Advisory Group on Molecular Screening and Toxicogenomics (EAGMST) launched a project to develop guidance for the reporting of omics data aimed at fostering further regulatory use. Here, we report on the ongoing development of the first formal reporting framework describing the processing and analysis of both transcriptomic and metabolomic data for regulatory toxicology. We introduce the modular structure, content, harmonization and strategy for trialling this reporting framework prior to its publication by the OECD.

Concentration- and time-dependent induction of Cyp1a and DNA damage response by benzo(a)pyrene in LMH three-dimensional spheroids

In vitro liver toxicity tests performed using cell lines cultured as two-dimensional (2D) monolayer have limited CYP450 activity and may be inadequate for screening chemicals that require activation to exert toxicity. Metabolic competence is greatly improved using three-dimensional (3D) cell culture. In this study, Cyp1a induction, and subsequent DNA damage response induced by benzo(a)pyrene (BaP) were compared in 2D monolayer cells and 3D spheroids of the chicken hepatic cell line, LMH. Cells were exposed to BaP (0.1-100 μM) for different durations: 8, 24, 35, or 48 hr. Cyp1a activity, mRNA expression of Cyp1a and DNA damage response (DDR) genes, and phosphorylation of H2AX (γH2AX) were determined using the EROD assay, a customized PCR array, and flow cytometry, respectively. EROD activity was induced at 8 hr and achieved maximal induction at 24 hr in spheroids; earlier time points than for monolayer cells. In spheroids, BaP exposure resulted in a concentration-dependent increase in Cyp1a4 mRNA expression at 8 hr followed by upregulation of DDR genes at 24 hr, whereas Cyp1a4 mRNA induction was only observed at 48 hr in monolayer cells. Cyp1a5 mRNA was induced at 8 hr in monolayer cells but maximum induction was greater in spheroids. An increase in γH2AX was observed at 24 hr in spheroids; this endpoint was not evaluated in monolayer cells. These results suggest that BaP metabolism precedes the DNA damage response and occurs earlier in 3D spheroids. This study demonstrates that LMH 3D spheroids could be a suitable metabolically-competent in vitro model to measure genotoxicity of chemicals that require metabolic activation by Cyp1a.

Characteristics of patients who had a stroke not initially identified during emergency prehospital assessment: a systematic review

Background

Around 25% of patients who had a stroke do not present with typical ‘face, arm, speech’ symptoms at onset, and are challenging for emergency medical services (EMS) to identify. The aim of this systematic review was to identify the characteristics of acute stroke presentations associated with inaccurate EMS identification (false negatives).

Method

We performed a systematic search of MEDLINE, EMBASE, CINAHL and PubMed from 1995 to August 2020 using key terms: stroke, EMS, paramedics, identification and assessment. Studies included: patients who had a stroke or patient records; ≥18 years; any stroke type; prehospital assessment undertaken by health professionals including paramedics or technicians; data reported on prehospital diagnostic accuracy and/or presenting symptoms. Data were extracted and study quality assessed by two researchers using the Quality Assessment of Diagnostic Accuracy Studies V.2 tool.

Results

Of 845 studies initially identified, 21 observational studies met the inclusion criteria. Of the 6934 stroke and Transient Ischaemic Attack patients included, there were 1774 (26%) false negative patients (range from 4 (2%) to 247 (52%)). Commonly documented symptoms in false negative cases were speech problems (n=107; 13%–28%), nausea/vomiting (n=94; 8%–38%), dizziness (n=86; 23%–27%), changes in mental status (n=51; 8%–25%) and visual disturbance/impairment (n=43; 13%–28%).

Conclusion

Speech problems and posterior circulation symptoms were the most commonly documented symptoms among stroke presentations that were not correctly identified by EMS (false negatives). However, the addition of further symptoms to stroke screening tools requires valuation of subsequent sensitivity and specificity, training needs and possible overuse of high priority resources.

Predictors of recognition of out of hospital cardiac arrest by emergency medical services call handlers in England: a mixed methods diagnostic accuracy study

Background

The aim of this study was to identify key indicator symptoms and patient factors associated with correct out of hospital cardiac arrest (OHCA) dispatch allocation. In previous studies, from 3% to 62% of OHCAs are not recognised by Emergency Medical Service call handlers, resulting in delayed arrival at scene.

Methods

Retrospective, mixed methods study including all suspected or confirmed OHCA patients transferred to one acute hospital from its associated regional Emergency Medical Service in England from 1/7/2013 to 30/6/2014. Emergency Medical Service and hospital data, including voice recordings of EMS calls, were analysed to identify predictors of recognition of OHCA by call handlers. Logistic regression was used to explore the role of the most frequently occurring (key) indicator symptoms and characteristics in predicting a correct dispatch for patients with OHCA.

Results

A total of 39,136 dispatches were made which resulted in transfer to the hospital within the study period, including 184 patients with OHCA. The use of the term ‘Unconscious’ plus one or more of symptoms ‘Not breathing/Ineffective breathing/Noisy breathing’ occurred in 79.8% of all OHCAs, but only 72.8% of OHCAs were correctly dispatched as such. ‘Not breathing’ was associated with recognition of OHCA by call handlers (Odds Ratio (OR) 3.76). The presence of key indicator symptoms ‘Breathing’ (OR 0.29), ‘Reduced or fluctuating level of consciousness’ (OR 0.24), abnormal pulse/heart rate (OR 0.26) and the characteristic ‘Female patient’ (OR 0.40) were associated with lack of recognition of OHCA by call handlers (p-values < 0.05).

Conclusions

There is a small proportion of calls in which cardiac arrest indicators are described but the call is not dispatched as such. Stricter adherence to dispatch protocols may improve call handlers’ OHCA recognition. The existing dispatch protocol would not be improved by the addition of further terms as this would be at the expense of dispatch specificity.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13049-020-00823-9.

Glucagon-like peptide-1 receptor agonists as neuroprotective agents for ischemic stroke: a systematic scoping review

Stroke mortality and morbidity is expected to rise. Despite considerable recent advances within acute ischemic stroke treatment, scope remains for development of widely applicable neuroprotective agents. Glucagon-like peptide-1 receptor agonists (GLP-1RAs), originally licensed for the management of Type 2 Diabetes Mellitus, have demonstrated pre-clinical neuroprotective efficacy in a range of neurodegenerative conditions. This systematic scoping review reports the pre-clinical basis of GLP-1RAs as neuroprotective agents in acute ischemic stroke and their translation into clinical trials. We included 35 pre-clinical studies, 11 retrospective database studies, 7 cardiovascular outcome trials and 4 prospective clinical studies. Pre-clinical neuroprotection was demonstrated in normoglycemic models when administration was delayed by up to 24 h following stroke induction. Outcomes included reduced infarct volume, apoptosis, oxidative stress and inflammation alongside increased neurogenesis, angiogenesis and cerebral blood flow. Improved neurological function and a trend towards increased survival were also reported. Cardiovascular outcomes trials reported a significant reduction in stroke incidence with semaglutide and dulaglutide. Retrospective database studies show a trend towards neuroprotection. Prospective interventional clinical trials are on-going, but initial indicators of safety and tolerability are favourable. Ultimately, we propose that repurposing GLP-1RAs is potentially advantageous but appropriately designed trials are needed to determine clinical efficacy and cost-effectiveness.

Clinical academic research internships for nurses, midwives and allied health professionals: a qualitative evaluation

BACKGROUND

Nurses, midwives and allied health professionals are integral to research, yet rarely engage simultaneously in research and clinical practice. Clinical academic internships offer a route for accessing academic research training.

AIM

To determine facilitators and barriers to nurses' participation and engagement in research internships, and to suggest improvements for future programmes.

DISCUSSION

The experiences of ten health professional research interns were explored, using a method based on a synthesis between grounded theory and content analysis. Four categories emerged: integrating clinical and research aspirations; support - or lack of it; the hidden curriculum; and the legacy effect. Respondents identified facilitators and barriers to engagement in these categories, including unforeseen challenges.

CONCLUSION

Formal support is necessary but is insufficient for fostering engagement and maximising benefits. Participation must be supported by colleagues and enabled by institutional structures. The potential effects of internships on engagement with research is considerable but requires collaboration between all stakeholders.

IMPLICATIONS FOR PRACTICE

Deeper institutional engagement is needed so that internship opportunities are fully supported by all colleagues and practically enabled by institutional structures. Future schemes should attempt to promote opportunities to collaborate through group projects to reduce researchers' isolation.

Eating well, living well and weight management: A co-produced semi-qualitative study of barriers and facilitators experienced by adults with intellectual disabilities

Adults with intellectual disabilities in England experience health inequalities. They are more likely than their non-disabled peers to be obese and at risk of serious medical conditions such as heart disease, stroke and type 2 diabetes. This semi-qualitative study engaged adults with intellectual disabilities in a co-production process to explore their perceived barriers and facilitators to eating well, living well and weight management. Nineteen participants with intellectual disabilities took part in four focus groups and one wider group discussion. They were supported by eight of their carers or support workers. Several barriers were identified including personal income restrictions, carers' and support workers' unmet training needs, a lack of accessible information, inaccessible services and societal barriers such as the widespread advertising of less healthy foodstuffs. A key theme of frustration with barriers emerged from analysis of participants' responses. Practical solutions suggested by participants included provision of clear and accessible healthy lifestyle information, reasonable adjustments to services, training, 'buddying' support systems or schemes and collaborative working to improve policy and practice.

A New Framework for Performing Cardiac Strain Analysis from Cine MRI Imaging in Mice

Cardiac magnetic resonance (MR) imaging is one of the most rigorous form of imaging to assess cardiac function in vivo. Strain analysis allows comprehensive assessment of diastolic myocardial function, which is not indicated by measuring systolic functional parameters using with a normal cine imaging module. Due to the small heart size in mice, it is not possible to perform proper tagged imaging to assess strain. Here, we developed a novel deep learning approach for automated quantification of strain from cardiac cine MR images. Our framework starts by an accurate localization of the LV blood pool center-point using a fully convolutional neural network (FCN) architecture. Then, a region of interest (ROI) that contains the LV is extracted from all heart sections. The extracted ROIs are used for the segmentation of the LV cavity and myocardium via a novel FCN architecture. For strain analysis, we developed a Laplace-based approach to track the LV wall points by solving the Laplace equation between the LV contours of each two successive image frames over the cardiac cycle. Following tracking, the strain estimation is performed using the Lagrangian-based approach. This new automated system for strain analysis was validated by comparing the outcome of these analysis with the tagged MR images from the same mice. There were no significant differences between the strain data obtained from our algorithm using cine compared to tagged MR imaging. Furthermore, we demonstrated that our new algorithm can determine the strain differences between normal and diseased hearts.

Medication-taking after stroke: a qualitative meta-synthesis of the perspectives of stroke survivors, informal carers and health professionals

BACKGROUND

Lifelong secondary prevention medication is recommended after stroke or transient ischaemic attack. However, poor medication adherence and persistence, which lead to suboptimal health outcomes, are common, but the reasons for this are not well understood, mainly because there have been few studies reporting adherence barriers in stroke survivors.

OBJECTIVE

The aim of this review was to undertake a meta-synthesis of qualitative studies of medication-taking after stroke. Outcomes of interest were: lived experiences, views and beliefs, and strategies and solutions used by community-dwelling stroke and transient ischaemic attack survivors, informal carers and health care professionals in relation to medication-taking.

METHOD

The review protocol was registered on PROSPERO (CRD42018086792). A search of online bibliographic databases was performed using key search terms of stroke, persistence, adherence and medication for years 1980-2018. Citation tracking was also carried out. Studies using qualitative or mixed methods were included. Systematic data extraction and synthesis were conducted using a meta-ethnographic approach.

RESULTS

Twelve studies were eligible for inclusion, with a total of 412 participants, two-thirds of whom were stroke survivors, ranging from 1 month to over 20 years post-stroke. Third-order themes identified were 'Medicines Work'-Information Work; Health Care Work; Carer Work; Emotional Work; Practical Work and an underpinning theme of Trust. However, many studies had significant methodological weaknesses.

CONCLUSIONS

This synthesis suggests that the burden of 'medicines work' after stroke is substantial and multifaceted. Its successful undertaking depends on mutual trust between stroke survivors, carers and health care professionals and trust in the benefits of medicines themselves.

The impact of educational interventions on clinicians' knowledge of radiation protection: An integrative review

OBJECTIVES

The aim of this review is to explore the impact of educational interventions on clinicians' knowledge of radiation protection.

KEY FINDINGS

Following a comprehensive search of MEDLINE and EMBASE from 2000 to 2018, 1795 studies were identified, eight of which met the criteria for this review. All eight studies utilised pretest-posttest designs and involved the education of medical students or doctors. All studies reported an increase in participants' knowledge of radiation protection, five of which were statistically significant. In two studies, over half of participants stated that education received would impact on their future imaging requesting practice.

CONCLUSION

Whilst a range of educational interventions have been shown to improve knowledge of radiation protection, there was wide variation in the study settings and type of educational programmes delivered. No studies assessed long-term knowledge retention or the impact on clinical practice. Therefore, robust research is needed to accurately measure the impact of educational programmes on knowledge of radiation protection in the UK and the implications this may have on referral practices.

IMPLICATIONS FOR PRACTICE

This review revealed that educational interventions are effective in increasing participants' knowledge levels of radiation protection. It is necessary to assess and ensure that this improvement in knowledge actually translates into an impact on referral practice/behaviour. The ideal outcome being that fewer unnecessary examinations are requested and our patients are protected from a needless increased radiation burden.

Healthcare practitioners' views and experiences of barriers and facilitators to weight management interventions for adults with intellectual disabilities

BACKGROUND

Obesity is common in adults with intellectual disabilities, yet little is known about how weight management interventions are provided for this population.

METHODS

Semi-structured interviews were held with 14 healthcare practitioners involved in weight management interventions in an English county. A study topic guide was developed to elicit practitioners' views and experiences of barriers and facilitators to weight management for adults with intellectual disabilities. Responses were analysed using thematic analysis.

RESULTS

Several barriers are involved in weight management for people with intellectual disabilities including communication challenges, general practitioners' lack of knowledge and awareness of weight management services, inconsistencies in caring support, resource constraints, wider external circumstances surrounding the individuals and motivational issues. Facilitators include reasonable adjustments to existing weight management services. However, there is a need for specialist weight management provision for people with intellectual disabilities.

CONCLUSIONS

This study provides suggestions for future research, policy and practice consideration.

Prioritization of 10 organic flame retardants using an avian hepatocyte toxicogenomic assay

As the number of chemicals developed and used by industry increases, the inherent limitations of traditional toxicology approaches become an unavoidable issue. To help meet the demand for toxicity evaluation, new methods, such as high-throughput toxicity screening, are currently being developed to permit rapid determination of toxic, molecular, and/or biochemical effects of a wide range of chemicals. In the present study, we demonstrate the utility of an avian in vitro toxicogenomics screening approach to determine the cytotoxic and transcriptomic effects of 10 organic flame retardants (OFRs) currently of international priority for ecological risk evaluation to prioritize and inform future toxicological studies. Hepatocytes from 2 avian species, chicken and double-crested cormorant, were prepared and exposed for 24 h to various concentrations (0-300 μM) of the following 10 OFRs: Chemical Abstracts Service registration numbers 29761-21-5, 56803-37-3 (p-tert-butylphenyl diphenyl phosphate [BPDP]), 65652-41-7, 68937-41-7 (phenol, isopropylated, phosphate [3:1] [IPPP]), 95906-11-9, 19186-97-1, 26040-51-7, 35948-25-5, 21850-44-2, and 25713-60-4. Cell viability, the 7-ethoxyresorufin-O-deethylase assay, and transcriptomic analysis using species-specific ToxChip polymerase chain reaction arrays were performed to evaluate the in vitro effect of these OFRs. Of the 10 OFRs assessed, BPDP and IPPP elicited the strongest cytotoxic and transcriptomic responses in both chicken and double-crested cormorant hepatocytes and are therefore recommended as priority candidates for further wildlife toxicological investigations. Environ Toxicol Chem 2018;37:3134-3144. © 2018 Crown in the right of Canada. Published by Wiley Periodicals Inc. on behalf of SETAC.

Next-to-Leading-Order QCD Corrections to Higgs Boson Plus Jet Production with Full Top-Quark Mass Dependence

We present the next-to-leading-order QCD corrections to the production of a Higgs boson in association with one jet at the LHC including the full top-quark mass dependence. The mass of the bottom quark is neglected. The two-loop integrals appearing in the virtual contribution are calculated numerically using the method of sector decomposition. We study the Higgs boson transverse momentum distribution, focusing on the high p_{t,H} region, where the top-quark loop is resolved. We find that the next-to-leading-order QCD corrections are large but that the ratio of the next-to-leading-order to leading-order result is similar to that obtained by computing in the limit of large top-quark mass.

The impact of education and training interventions for nurses and other health care staff involved in the delivery of stroke care: An integrative review

OBJECTIVES

The aim of this review was to explore the impact of stroke education and training of nurses and other health care staff involved in the delivery of stroke care.

DESIGN

We performed an integrative review, following PRISMA guidance where possible.

DATA SOURCES

We searched MEDLINE, ERIC, PubMed, AMED, EMBASE, HMIC, CINAHL, Google Scholar, IBSS, Web of Knowledge, and the British Nursing Index from 1980 to 2016.

REVIEW METHODS

Any intervention studies were included if they focused on the education or training of nurses and other health care staff in relation to stroke care. Articles that appeared to meet the inclusion criteria were read in full. Data were extracted from the articles, and the study quality assessed by two researchers. We assessed risk of bias of included studies using a pre-specified tool based on Cochrane guidance.

RESULTS

Our initial search identified 2850 studies of which 21 met the inclusion criteria. Six studies were randomised controlled trials, and one was an interrupted time series. Fourteen studies were quasi-experimental: eight were pretest-posttest; five were non-equivalent groups; one study had a single assessment. Thirteen studies used quality of care outcomes and eight used a patient outcome measure. None of the studies was identified as having a low risk of bias. Only nine studies used a multi-disciplinary approach to education and training and nurses were often taught alone. Interactive education and training delivered to multi-disciplinary stroke teams, and the use of protocols or guidelines tended to be associated with a positive impact on patient and quality of care outcomes.

CONCLUSIONS

Practice educators should consider the delivery of interactive education and training delivered to multi-disciplinary groups, and the use of protocols or guidelines, which tend to be associated with a positive impact on both patient and quality of care outcomes. Future research should incorporate a robust design.

An integrative review of multicomponent weight management interventions for adults with intellectual disabilities

BACKGROUND

Obesity is more prevalent in people with intellectual disabilities and increases the risk of developing serious medical conditions. UK guidance recommends multicomponent weight management interventions (MCIs), tailored for different population groups.

METHODS

An integrative review utilizing systematic review methodology was conducted to identify the types of MCIs delivered to adults with intellectual disabilities.

FINDINGS

Five studies were identified. All of the studies' MCIs were tailored for adults with intellectual disabilities. Tailoring included measures such as simplified communication tools, individualized sessions, and the presence of carers where appropriate.

CONCLUSIONS

Emerging evidence suggests ways in which MCIs can be tailored for adults with intellectual disabilities but, given the few studies identified, it is not possible to recommend how they can be routinely tailored. Further studies are justified for adults with intellectual disabilities at risk of obesity-related conditions.

Catbirds are the New Chickens: High Sensitivity to a Dioxin-like Compound in a Wildlife Species

Dioxins and dioxin-like compounds (DLCs) are highly toxic and persistent global pollutants with extremely large differences in sensitivity across taxonomic groups. The chicken has long been considered uniquely sensitive to DLCs among avian species; but DLC toxicity in nondomesticated birds is largely untested, and the relevance of the chicken as an ecological model is uncertain. New approaches that use genotyping of the AHR1 ligand binding domain to screen for DLC sensitivity among avian species predicted that the gray catbird, a relevant wildlife species, is also highly sensitive. We tested this prediction using egg injections of a dioxin-like PCB (PCB-126) and found that the catbird is at least as sensitive as the chicken to DLCs, based on both embryotoxicity and mRNA induction of phase I metabolizing enzymes (CYP1A4/5). This study is the first to confirm that there are wildlife species as sensitive as the chicken and demonstrates how using predictive genotyping methods and targeted bioassays can focus toxicity assessments on ecologically relevant species.

Erratum: Higgs Boson Pair Production in Gluon Fusion at Next-to-Leading Order with Full Top-Quark Mass Dependence [Phys. Rev. Lett. 117, 012001 (2016)]

This corrects the article DOI: 10.1103/PhysRevLett.117.012001.

Higgs Boson Pair Production in Gluon Fusion at Next-to-Leading Order with Full Top-Quark Mass Dependence

We present the calculation of the cross section and invariant mass distribution for Higgs boson pair production in gluon fusion at next-to-leading order (NLO) in QCD. Top-quark masses are fully taken into account throughout the calculation. The virtual two-loop amplitude has been generated using an extension of the program GoSam supplemented with an interface to Reduze for the integral reduction. The occurring integrals have been calculated numerically using the program SecDec. Our results, including the full top-quark mass dependence for the first time, allow us to assess the validity of various approximations proposed in the literature, which we also recalculate. We find substantial deviations between the NLO result and the different approximations, which emphasizes the importance of including the full top-quark mass dependence at NLO.

Use of a Novel Double-Crested Cormorant ToxChip PCR Array and the EROD Assay to Determine Effects of Environmental Contaminants in Primary Hepatocytes

In vitro screening tools and 'omics methods are increasingly being incorporated into toxicity studies to determine mechanistic effects of chemicals and mixtures. To date, the majority of these studies have been conducted with well-characterized laboratory animal models. In the present study, well-established methods developed for chicken embryonic hepatocyte (CEH) studies were extended to a wild avian species, the double-crested cormorant (DCCO; Phalacrocorax auritus), in order to compare the effects of several environmental contaminants on cytotoxicity, ethoxyresorufin O-deethylase (EROD) activity, and mRNA expression. Five organic flame retardants and one plasticizer decreased cormorant hepatocyte viability in a similar manner to that observed in previous studies with CEH. EROD activity was induced in a concentration-dependent manner following exposure to two dioxin-like chemicals and the calculated EC50 values were concordant with domestic avian species from similar species sensitivity categories. Transcriptomic effects were determined using a novel DCCO PCR array, which was designed, constructed and validated in our laboratory based on a commercially available chicken PCR array. The DCCO array has 27 target genes covering a wide range of toxicity pathways. Gene profiles were variable among the 10 chemicals screened; however, good directional concordance was observed with regard to results previously obtained in CEH. Overall, the application of well-established methods (i.e., CEH and chicken PCR array) to the double-crested cormorant demonstrated the portability of the techniques to an indicator species of ecological relevance.

Feathers as a source of RNA for genomic studies in avian species

Dioxins and dioxin-like chemicals (DLCs) cause a suite of adverse effects in terrestrial species. Most of the adverse effects occur subsequent to binding to the aryl hydrocarbon receptor. Avian species vary in their sensitivity to the effects of DLCs and current research indicates that this is mediated by variations in the amino acid sequence within the ligand binding domain (LBD) of the aryl hydrocarbon receptor 1 (AHR1). Eighty-eight avian species have been classified into three broad categories of sensitivity, based on the amino acid variations within the AHR1 LBD: sensitive type 1 (Ile324_Ser380), moderately sensitive type 2 (Ile324_Ala380), and relatively insensitive type 3 (Val324_Ala380). Risk assessment of avian species can be complicated due to the variability in sensitivity among species. A predictive tool for selecting the priority species at a given site would have broad implications for the risk assessment community. We present a method for AHR1 genotyping using plucked feathers as a source of RNA. The method is extremely robust, requires minimal sample processing and handling, and eliminates the need for blood sampling or tissue collection from the species of interest. Using this method we were able to determine the amino acid sequence of the AHR LBD of three avian species: the chicken, the herring gull, and the zebra finch, and to categorize them based on the identity of amino acids at key sites within the LBD.

A clinical investigation of force delivery systems for orthodontic space closure

OBJECTIVE

To investigate the force retention, and rates of space closure achieved by elastomeric chain and nickel titanium coil springs.

DESIGN

Randomized clinical trial.

SETTING

Eastman Dental Hospital, London and Queen Mary's University Hospital, Roehampton, 1998-2000.

SUBJECTS, MATERIALS AND METHODS

Twenty-two orthodontic patients, wearing the pre-adjusted edgewise appliance undergoing space closure in opposing quadrants, using sliding mechanics on 0.019 x 0.025-inch posted stainless steel archwires. Medium-spaced elastomeric chain [Durachain, OrthoCare (UK) Ltd., Bradford, UK] and 9-mm nickel titanium coil springs [OrthoCare (UK) Ltd.] were placed in opposing quadrants for 15 patients. Elastomeric chain only was used in a further seven patients. The initial forces on placement and residual forces at the subsequent visit were measured with a dial push-pull gauge [Orthocare (UK) Ltd]. Study models of eight patients were taken before and after space closure, from which measurements were made to establish mean space closure.

MAIN OUTCOME MEASURES

The forces were measured in grammes and space closure in millimetres.

RESULTS

Fifty-nine per cent (31/53) of the elastomeric sample maintained at least 50 per cent of the initial force over a time period of 1-15 weeks. No sample lost all its force, and the mean loss was 47 per cent (range: 0-76 per cent). Nickel titanium coil springs lost force rapidly over 6 weeks, following that force levels plateaued. Forty-six per cent (12/26) maintained at least 50 per cent of their initial force over a time period of 1-22 weeks, and mean force loss was 48 per cent (range: 12-68 per cent). The rate of mean weekly space closure for elastomeric chain was 0.21 mm and for nickel titanium coil springs 0.26 mm. There was no relationship between the initial force applied and rate of space closure. None of the sample failed during the study period giving a 100 per cent response rate.

CONCLUSIONS

In clinical use, the force retention of elastomeric chain was better than previously concluded. High initial forces resulted in high force decay. Nickel titanium coil springs and elastomeric chain closed spaces at a similar rate.

Amino acid sequence of the AhR1 ligand-binding domain predicts avian sensitivity to dioxin like compounds: in vivo verification in European starlings

Research has demonstrated that the sensitivity of avian species to the embyrotoxic effects of dioxin-like compounds can be predicted by the amino acid identities at two key sites within the ligand-binding domain of the aryl hydrocarbon receptor 1 (AhR1). The domestic chicken (Gallus gallus domesticus) has been established as a highly sensitive species to the toxic effects of dioxin-like compounds. Results from genotyping and in vitro assays predict that the European starling (Sturnus vulgaris) is also highly sensitive to dioxin-like compound toxicity. The objective of the present study was to test that prediction in vivo. To do this, we used egg injections in field nesting starlings with 3,3',4,4',5-pentachlorobiphenyl (PCB-126), a dioxin-like polychlorinated biphenyl. Eggs were dosed with either the vehicle control or 1 of 5 doses (1.4, 7.1, 15.9, 32.1, and 52.9 ng PCB-126/g egg). A dose-dependent increase in embryo mortality occurred, and the median lethal dose (LD50; 95% confidence interval [CI]) was 5.61 (2.33-9.08) ng/g. Hepatic CYP1A4/5 messenger RNA (mRNA) expression in hatchlings also increased in a dose-dependent manner, with CYP1A4 being more induced than CYP1A5. No effect of dose on morphological measures was seen, and we did not observe any overt malformations. These results indicate that, other than the chicken, the European starling is the most sensitive species to the effects of PCB-126 on avian embryo mortality reported to date, which supports the prediction of relative sensitivity to dioxin-like compounds based on amino acid sequence of the AhR1.

Ethoxyresorufin-O-deethylase (EROD) induction by TCDD, PeCDF and PCB 126 in bobwhite quail hepatocytes

World Health Organization (WHO) toxic equivalency factors are used to calculate toxic equivalent (TEQ) concentrations of complex mixtures of dioxin-like compounds (DLCs), such as polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and polychlorinated biphenyls (PCBs), for mammals, fish and birds. The TEQ concept assumes that all species of a taxa respond with similar sensitivity to individual DLCs, but several reports do not support this assumption for birds. Our laboratory is conducting research to attempt to uncover the fundamental mechanism(s) underlying the reasons why avian species differ in sensitivity to DLCs. The present study determined concentration-dependent effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 2,3,4,7,8-pentachlorodibenzofuran (PeCDF) and 3,3',4,4',5-pentachlorobiphenyl (PCB 126) on ethoxyresorufin-O-deethylase (EROD) activity in primary cultures of northern bobwhite quail (Colinus virginianus) hepatocytes. Bobwhite quail were studied because (1) this species is used in the laboratory for toxicity testing and (2) the amino acids at all locations within the ligand binding domain (LBD) of aryl hydrocarbon receptor 1 (AHR1) in bobwhite quail and ring necked pheasant (Phasianus colchicus) are identical. Because earlier work indicated the importance of the identity of amino acids at key sites within the AHR1 LBD, we hypothesized that bobwhite quail and ring necked pheasant hepatocytes should have similar sensitivity to EROD induction by DLCs. ECthreshold-based relative sensitivity of the bobwhite quail compared to chicken for TCDD, PeCDF and PCB 126 was 0.11, 0.17 and 0.02, respectively. The rank order of potency was PeCDF > TCDD > PCB 126. The results confirm that bobwhite quail and ring-necked pheasant hepatocytes have similar sensitivity to EROD induction by TCDD, PeCDF and PCB 126.

Species-specific relative AHR1 binding affinities of 2,3,4,7,8-pentachlorodibenzofuran explain avian species differences in its relative potency

Results of recent studies showed that 2,3,4,7,8-pentachlorodibenzofuran (PeCDF) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) are equipotent in domestic chicken (Gallus gallus domesticus) while PeCDF is more potent than TCDD in ring-necked pheasant (Phasianus colchicus) and Japanese quail (Coturnix japonica). To elucidate the mechanism(s) underlying these differences in relative potency of PeCDF among avian species, we tested the hypothesis that this is due to species-specific differential binding affinity of PeCDF to the aryl hydrocarbon receptor 1 (AHR1). Here, we modified a cell-based binding assay that allowed us to measure the binding affinity of dioxin-like compounds (DLCs) to avian AHR1 expressed in COS-7 (fibroblast-like cells). The results of the binding assay show that PeCDF and TCDD bind with equal affinity to chicken AHR1, but PeCDF binds with greater affinity than TCDD to pheasant (3-fold) and Japanese quail (5-fold) AHR1. The current report introduces a COS-7 whole-cell binding assay and provides a mechanistic explanation for differential relative potencies of PeCDF among species of birds.

Emergency Stroke Calls: Obtaining Rapid Telephone Triage (ESCORTT) – a programme of research to facilitate recognition of stroke by emergency medical dispatchers

Background

Rapid access to emergency stroke care can reduce death and disability by enabling immediate provision of interventions such as thrombolysis, physiological monitoring and stabilisation. One of the ways that access to services can be facilitated is through emergency medical service (EMS) dispatchers. The sensitivity of EMS dispatchers for identifying stroke is < 50%. Studies have shown that activation of the EMSs is the single most important factor in the rapid triage and treatment of acute stroke patients.

Objectives

To facilitate recognition of stroke by emergency medical dispatchers (EMDs).

Design

An eight-phase mixed-methods study. Phase 1: a retrospective cohort study exploring stroke diagnosis. Phase 2: semi-structured interviews exploring public and EMS interactions. Phases 3 and 4: a content analysis of 999 calls exploring the interaction between the public and EMDs. Phases 5–7: development and implementation of stroke-specific online training (based on phases 1–4). Phase 8: an interrupted time series exploring the impact of the online training.

Setting

One ambulance service and four hospitals.

Participants

Patients arriving at hospital by ambulance with stroke suspected somewhere on the stroke pathway (phases 1 and 8). Patients arriving at hospital by ambulance with a final diagnosis of stroke (phase 2). Calls to the EMSs relating to phase 1 patients (phases 3 and 4). EMDs (phase 7).

Interventions

Stroke-specific online training package, designed to improve recognition of stroke for EMDs.

Main outcome measures

Phase 1: symptoms indicative of a final and dispatch diagnosis of stroke. Phase 2: factors involved in the decision to call the EMSs when stroke is suspected. Phases 3 and 4: keywords used by the public when describing stroke and non-stroke symptoms to EMDs. Phase 8: proportion of patients with a final diagnosis of stroke correctly dispatched as stroke by EMDs.

Results

Phase 1: for patients with a final diagnosis of stroke, facial weakness and speech problems were significantly associated with an EMD code of stroke. Phase 2: four factors were identified – perceived seriousness; seeking and receiving lay or professional advice; caller’s description of symptoms and emotional response to symptoms. Phases 3 and 4: mention of ‘stroke’ or one or more Face Arm Speech Test (FAST) items is much more common in stroke compared with non-stroke calls. Consciousness level was often difficult for callers to determine and/or communicate. Phase 8: there was a significant difference (p = 0.003) in proportions correctly dispatched as stroke – before the training was implemented 58 out of 92 (63%); during implementation of training 42 out of 48 (88%); and after training implemented 47 out of 59 (80%).

Conclusions

EMDs should be aware that callers are likely to describe loss of function (e.g. unable to grip) rather than symptoms (e.g. weakness) and that callers using the word ‘stroke’ or describing facial weakness, limb weakness or speech problems are likely to be calling about a stroke. Ambiguities and contradictions in dialogue about consciousness level arise during ambulance calls for suspected and confirmed stroke. The online training package improved recognition of stroke by EMDs. Recommendations for future research include testing the effectiveness of the Emergency Stroke Calls: Obtaining Rapid Telephone Triage (ESCORTT) training package on the recognition of stroke across other EMSs in England; and exploring the impact of the early identification of stroke by call handlers on patient and process outcomes.

Funding

The National Institute for Health Research Programme Grants for Applied Research programme.

Training emergency services' dispatchers to recognise stroke: an interrupted time-series analysis

Background

Stroke is a time-dependent medical emergency in which early presentation to specialist care reduces death and dependency. Up to 70% of all stroke patients obtain first medical contact from the Emergency Medical Services (EMS). Identifying ‘true stroke’ from an EMS call is challenging, with over 50% of strokes being misclassified. The aim of this study was to evaluate the impact of the training package on the recognition of stroke by Emergency Medical Dispatchers (EMDs).

Methods

This study took place in an ambulance service and a hospital in England using an interrupted time-series design. Suspected stroke patients were identified in one week blocks, every three weeks over an 18 month period, during which time the training was implemented. Patients were included if they had a diagnosis of stroke (EMS or hospital). The effect of the intervention on the accuracy of dispatch diagnosis was investigated using binomial (grouped) logistic regression.

Results

In the Pre-implementation period EMDs correctly identified 63% of stroke patients; this increased to 80% Post-implementation. This change was significant (p=0.003), reflecting an improvement in identifying stroke patients relative to the Pre-implementation period both the During-implementation (OR=4.10 [95% CI 1.58 to 10.66]) and Post-implementation (OR=2.30 [95% CI 1.07 to 4.92]) periods. For patients with a final diagnosis of stroke who had been dispatched as stroke there was a marginally non-significant 2.8 minutes (95% CI −0.2 to 5.9 minutes, p=0.068) reduction between Pre- and Post-implementation periods from call to arrival of the ambulance at scene.

Conclusions

This is the first study to develop, implement and evaluate the impact of a training package for EMDs with the aim of improving the recognition of stroke. Training led to a significant increase in the proportion of stroke patients dispatched as such by EMDs; a small reduction in time from call to arrival at scene by the ambulance also appeared likely. The training package has been endorsed by the UK Stroke Forum Education and Training, and is free to access on-line.

"Can you send an ambulance please?": a comparison of callers' requests for emergency medical dispatch in non-stroke and stroke calls

BACKGROUND

Identifying 'true stroke' from an emergency medical services (EMS) call is challenging, with over 50% of strokes being misclassified. In a previous study, we examined the relationship between callers' descriptions of stroke symptoms to the emergency medical dispatcher and the subsequent classification and prioritisation of EMS response. The aim of this subsequent study was to explore further the use of keywords by callers when making emergency calls, comparing stroke and non-stroke calls.

METHODS

All non-stroke calls to one EMS dispatch centre between 8 March 2010 and 14 March 2010 were analysed. These were compared with the stroke calls made to one EMS dispatch centre between 1 October 2006 and 30 September 2007. Content analysis was used to explore the problems described by the caller, and findings were compared between non-stroke and stroke calls.

RESULTS

277 non-stroke calls were identified. Only eight (3%) callers mentioned stroke, 12 (4%) and 11 (4%) mentioned limb weakness and speech problems, respectively, while no caller mentioned more than one classic stroke symptom. This contrasted with 473 stroke calls, where 188 (40%) callers mentioned stroke, 70 (15%) limb weakness and 72 (15%) speech problems, and 14 (3%) mentioned more than one classic stroke symptom.

CONCLUSIONS

People who contact the EMS about non-stroke conditions rarely say stroke, limb weakness, speech problems or facial weakness. These words are more frequently used when people contact the EMS about stroke, although many calls relating to stroke patients do not mention any of these keywords.

Cytochrome P4501A induction in primary cultures of embryonic European starling hepatocytes exposed to TCDD, PeCDF and TCDF

Novel methods that predict the sensitivity of avian embryos to the toxic effects of dioxin-like compounds (DLCs) using either (1) knowledge of the identity of amino acids at key sites within the ligand binding domain of aryl hydrocarbon receptor 1 (AHR1) or (2) a luciferase reporter gene assay that measures AHR1 activation were recently reported. Results from both methods predict that European starling (Sturnus vulgaris) and domestic chicken (Gallus gallus domesticus) embryos have similar sensitivity to the biochemical and toxic effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 2,3,4,7,8-pentachlorodibenzofuran (PeCDF) and 2,3,7,8-tetrachlorodibenzofuran (TCDF). Chicken embryos are highly sensitive to DLC toxicity, and the prediction that starlings are equally sensitive is surprising given their widespread distribution and large population size. In an attempt to learn more about starling sensitivity to DLCs, we determined concentration-dependent effects of TCDD, PeCDF and TCDF on cytochrome P4501A4 and 1A5 (CYP1A4 and 1A5) mRNA levels in primary cultures of hepatocytes prepared from embryonic European starlings. It has been demonstrated that the sensitivity of avian hepatocytes to CYP1A4/5 induction is well correlated with LD50 values of DLCs for several avian species. The results of the present study indicate that European starling hepatocytes are indeed as sensitive as chicken hepatocytes to CYP1A4/5 induction after exposure to TCDD. However, starling hepatocytes are less sensitive than chicken hepatocytes to CYP1A4/5 induction by PeCDF and TCDF.

Cytochrome P4501A induction in avian hepatocyte cultures exposed to polychlorinated biphenyls: comparisons with AHR1-mediated reporter gene activity and in ovo toxicity

Avian-specific toxic equivalency factors (TEFs) were developed by the World Health Organization to simplify environmental risk assessments of dioxin-like compounds (DLCs), but TEFs do not account for differences in the toxic and biochemical potencies of DLCs among species of birds. Such variability may be due to differences in species sensitivity to individual DLCs. The sensitivity of avian species to DLCs was recently associated with the identity of amino acids 324 and 380 in the aryl hydrocarbon receptor 1 (AHR1) ligand binding domain. A luciferase reporter gene (LRG) assay, measuring AHR1-mediated induction of a cytochrome P450 1A5 (CYP1A5) reporter gene, in combination with a species' AHR1 ligand binding domain sequence, were also shown to predict avian species sensitivity to polychlorinated biphenyls (PCBs) and PCB relative potency in a given species. The goals of the present study were to (1) characterize the concentration-dependent effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin and PCBs 126, 77, 105 and 118 on induction of ethoxyresorufin O-deethylase (EROD) activity and CYP1A4/5 mRNA in chicken, ring-necked pheasant and Japanese quail embryo hepatocytes and (2) compare these in vitro results to those previously generated by the LRG assay and in ovo toxicity studies. EROD activity and CYP1A4/5 mRNA expression data support and complement the findings of the LRG assay. CYP1A enzyme activity and mRNA expression were significantly correlated both with luciferase activity and in ovo toxicity induced by PCBs. Relative potency values were generally similar between the LRG and EROD assays and indicate that the relative potency of some PCBs may differ among species.

Amino acid sequence of the ligand-binding domain of the aryl hydrocarbon receptor 1 predicts sensitivity of wild birds to effects of dioxin-like compounds

The sensitivity of avian species to the toxic effects of dioxin-like compounds (DLCs) varies up to 1000-fold among species, and this variability has been associated with interspecies differences in aryl hydrocarbon receptor 1 ligand-binding domain (AHR1 LBD) sequence. We previously showed that LD(50) values, based on in ovo exposures to DLCs, were significantly correlated with in vitro EC(50) values obtained with a luciferase reporter gene (LRG) assay that measures AHR1-mediated induction of cytochrome P4501A in COS-7 cells transfected with avian AHR1 constructs. Those findings suggest that the AHR1 LBD sequence and the LRG assay can be used to predict avian species sensitivity to DLCs. In the present study, the AHR1 LBD sequences of 86 avian species were studied, and differences at amino acid sites 256, 257, 297, 324, 337, and 380 were identified. Site-directed mutagenesis, the LRG assay, and homology modeling highlighted the importance of each amino acid site in AHR1 sensitivity to 2,3,7,8-tetrachlorodibenzo-p-dioxin and other DLCs. The results of the study revealed that (1) only amino acids at sites 324 and 380 affect the sensitivity of AHR1 expression constructs of the 86 avian species to DLCs and (2) in vitro luciferase activity of AHR1 constructs containing only the LBD of the species of interest is significantly correlated (r (2) = 0.93, p < 0.0001) with in ovo toxicity data for those species. These results indicate promise for the use of AHR1 LBD amino acid sequences independently, or combined with the LRG assay, to predict avian species sensitivity to DLCs.

Induction of cytochrome P4501A by highly purified hexachlorobenzene in primary cultures of ring-necked pheasant and Japanese quail embryo hepatocytes

Primary cultures of ring-necked pheasant (Phasianus colchicus) and Japanese quail (Coturnix japonica) embryo hepatocytes were used to compare the potencies of highly purified hexachlorobenzne (HCB-P), reagent-grade HCB (RG-HCB) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) as inducers of ethoxyresorufin O-deethylase (EROD) activity, cytochrome P4501A (CYP1A4) messenger ribonucleic acid (mRNA) and CYP1A5 mRNA. HCB-P, RG-HCB and TCDD all induced EROD activity and up-regulated CYP1A4 and CYP1A5 mRNA. Induction was not caused by contamination of HCB with polychlorinated dibenzo-p-dioxins, dibenzofurans or biphenyls. Based upon a comparison of the EC(50) and EC(threshold) values for EROD and CYP1A4/5 concentration-response curves, the potency of HCB relative to TCDD was 0.001 in ring-necked pheasant and 0.01 in Japanese quail embryo hepatocytes. Differences in species sensitivity to HCB were found to be mainly dictated by differences in species sensitivity to TCDD rather than differences in the absolute potency of HCB. Consequently, ring-necked pheasant and Japanese quail embryo hepatocytes were found to be equally sensitive to HCB exposure. Species sensitivity comparisons were also made with chicken (Gallus gallus domesticus) and revealed that chicken embryo hepatocytes were less responsive to EROD induction (lower maximal response) by HCB compared to the embryo hepatocytes of pheasant and quail.

Sequence and in vitro function of chicken, ring-necked pheasant, and Japanese quail AHR1 predict in vivo sensitivity to dioxins

There are large differences in sensitivity to the toxic and biochemical effects of dioxins and dioxin-like compounds (DLCs) among vertebrates. Previously, we demonstrated that the difference in sensitivity between domestic chicken (Gallus gallus domesticus) and common tern (Sterna hirundo) to aryl hydrocarbon receptor 1 (AHR1)-dependent changes in gene expression following exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is based upon the identities of the amino acids at two sites within the ligand binding domain of AHR1 (chicken--highly sensitive; Ile324_Ser380 vs common tern--250-fold less sensitive than chicken; Val325_Ala381). Here, we tested the hypotheses that (i) the sensitivity of other avian species to TCDD, 2,3,4,7,8-pentachlorodibenzofuran (PeCDF), and 2,3,7,8-tetrachlorodibenzofuran (TCDF) is also determined by the amino acids at sites that are equivalent to sites 324 and 380 in chicken, and (ii) Ile324_Ala380 and Val324_Ser380 genotypes confer intermediate sensitivity to DLCs in birds. We compared ligand-induced transactivation function of full-length AHR1s from chicken, common tern, ring-necked pheasant (Phasianus colchicus; Ile324_Ala380) and Japanese quail (Coturnix japonica; Val324_Ala380), and three Japanese quail AHR1 mutants. The results support our hypothesis that avian species can be grouped into three general classes of sensitivity to DLCs. Both AHR1 genotype and in vitro transactivation assays predict in vivo sensitivity. Contrary to the assumption that TCDD is the most potent DLC, PeCDF was more potent than TCDD at activating Japanese quail (13- to 26-fold) and common tern (23- to 30-fold) AHR1. Our results support and expand previous in vitro and in vivo work that demonstrated ligand-dependent species differences in AHR1 affinity. The findings and methods will be of use for DLC risk assessments.

The Identification of Acute Stroke: An Analysis of Emergency Calls

Background

Accurate dispatch of emergency medical services at the onset of acute stroke is vital in expediting assessment and treatment. We examined the relationship between callers' description of potential stroke symptoms to the emergency medical dispatcher and the subsequent classification and prioritisation of emergency medical services response.

Aim

To identify key ‘indicator’ words used by people making emergency calls for suspected stroke, comparing these with the subsequent category of response given by the emergency medical dispatcher.

Method

A retrospective chart review (hospital and emergency medical services) in North West England (October 1, 2006 to September 30, 2007) identified digitally recorded emergency medical services calls, which related to patients who had a diagnosis of suspected stroke at some point on the stroke pathway (from the emergency medical services call taker through to final medical diagnosis). Using content analysis, words used to describe stroke by the caller were recorded. A second researcher independently followed the same procedure in order to produce a list of ‘indicator’ words. Description of stroke-specific and nonstroke-specific problems reported by the caller was compared with subsequent emergency medical services dispatch coding and demographic features.

Results

Six hundred forty-three calls were made to emergency medical services of which 592 (92%) had complete emergency medical services and hospital data. The majority of callers were female (67%) and family members (55%). The most frequently reported problems first said by callers to the emergency medical dispatcher were collapse or fall (26%) and stroke (25%). Callers who identified that the patient was having a stroke were correct in 89% of cases. Calls were dispatched as stroke in 45% of cases, of which 83% had confirmed stroke. Of the first reported problems, Face Arm Speech Test stroke symptoms were mentioned in less than 5% of calls, with speech problems being the most common symptom. No callers mentioned all three Face Arm Speech Test symptoms.

Conclusion

Callers who contacted emergency medical services for suspected stroke and said stroke as the first reported problem were often correct. Calls categorised as stroke by the emergency medical dispatcher were commonly confirmed as stroke in the hospital. Speech problems were the most commonly reported element of the Face Arm Speech Test test to be reported by callers. Recognition of possible stroke diagnosis in fall and other presentations should be considered by emergency medical dispatchers. Further development and training are needed in the community to improve prehospital stroke recognition in order to expedite hyperacute stroke care.

Callers' experiences of making emergency calls at the onset of acute stroke: a qualitative study

BACKGROUND

Rapid access to emergency medical services (EMS) is essential at the onset of acute stroke, but significant delays in contacting EMS often occur.

OBJECTIVE

To explore factors that influence the caller's decision to contact EMS at the onset of stroke, and the caller's experiences of the call.

METHODS

Participants were identified through a purposive sample of admissions to two hospitals via ambulance with suspected stroke. Participants were interviewed using open-ended questions and content analysis was undertaken.

RESULTS

50 participants were recruited (median age 62 years, 68% female). Only one of the callers (2%) was the patient. Two themes were identified that influenced the initial decision to contact EMS at the onset of stroke: perceived seriousness, and receipt of lay or professional advice. Two themes were identified in relation to the communication between the caller and the call handler: symptom description by the caller, and emotional response to onset of stroke symptoms.

CONCLUSIONS

Many callers seek lay or professional advice prior to contacting EMS and some believe that the onset of acute stroke symptoms does not warrant an immediate 999 call. More public education is needed to improve awareness of stroke and the need for an urgent response.

Stroke knowledge and awareness: an integrative review of the evidence

BACKGROUND

the recognition of stroke symptoms by the public and activation of the emergency medical services (EMS) are the most important factors in instigating pre-hospital stroke care. Studies have suggested that poor recognition of the warning signs of stroke is the main cause of delay in accessing the EMS.

METHODS

an integrative review of published studies about stroke knowledge and awareness was performed by searching online bibliographic databases, using keywords, from 1966 to 2008. Studies were included in the review if they focussed on risk factors, signs and symptoms, action and information. Each study was reviewed by two researchers (SJ and MJ).

RESULTS

we identified 169 studies of which 39 were included in the review. The ability to name one risk factor for stroke varied between studies, ranging from 18% to 94% when asked open-ended questions and from 42% to 97% when asked closed questions. The ability to name one symptom ranged from 25% to 72% when asked open-ended questions and from 95% to 100% when asked closed questions. When asked what action people would take if they thought they were having a stroke, between 53% and 98% replied that they would call the EMS. People generally obtained information about stroke from family and friends. Older members of the population, ethnic minority groups and those with lower levels of education had consistently poor levels of stroke knowledge.

CONCLUSIONS

generally, levels of knowledge about recognising and preventing stroke were poor. Nevertheless, most participants stated they would contact the EMS at the onset of stroke symptoms.

Effects of 18 perfluoroalkyl compounds on mRNA expression in chicken embryo hepatocyte cultures

Many studies have characterized the effects of perfluoroalkyl compounds (PFCs) in mammalian species, but limited information exists on the effects of PFCs in birds. PFCs have been detected in serum and liver of avian wildlife worldwide. While the molecular mechanisms have yet to be elucidated in detail, PFCs alter lipid metabolism through peroxisome proliferation, xenobiotic metabolism by activating the cytochrome P450 (CYP) system, and serum cholesterol levels by inducing or repressing key genes. Here, we employed a simple messenger RNA (mRNA) screening method using quantitative PCR to assess the effects of PFCs on mRNA expression in chicken embryo hepatocytes (CEH). CEH cultures were treated with perfluoroalkyl sulfonates and perfluoroalkyl carboxylates of varying chain lengths and linear or technical grade potassium perfluoro-1-octane sulfonate (L-PFOS and T-PFOS). T-PFOS comprised 80% perfluorooctane sulfonate isomers (62% linear) and various PFCs and inorganic salts. Relative mRNA expression levels of the following genes were examined: acyl-CoA oxidase (ACOX), liver fatty acid-binding protein (L-FABP), CYP1A4/1A5 and CYP4B1, 3-hydroxy-3-methylglutaryl-Coenzyme A (HMG-CoA) reductase, and sterol regulatory element-binding protein 2 (SREBP2). Compared to L-PFOS, T-PFOS altered the mRNA expression level of more genes and produced greater fold changes. L-FABP was upregulated by PFCs greater than or equal to eight carbons, while CYPs were upregulated by PFCs less than or equal to eight carbons. ACOX, HMG-CoA, and SREBP2 showed little to no change following PFC exposure. This study is the first to expose CEH cultures to multiple PFCs in vitro and demonstrates that exposure to PFC solutions of different isomeric content or chain length causes variable transcriptional responses.

Effects of co-exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin and perfluorooctane sulfonate or perfluorooctanoic acid on expression of cytochrome P450 isoforms in chicken (Gallus gallus) embryo hepatocyte cultures

In this study we investigated the effect of a single-compound exposure or two compound co-exposure to tetrachlorodibenzo-p-dioxin (TCDD) plus perfluorooctane sulfonate (PFOS) or perfluorooctanoic acid (PFOA) on the mRNA expression of cytochromes P450 (CYP) 1A4, 4V2 and 3A37, ethoxyresorufin-O-deethylase (EROD) activity and cell viability in chicken (Gallus gallus domesticus) embryo primary hepatocyte cultures. Cell viability after 24 h of incubation was significantly decreased in cells exposed to PFOS at concentrations between 30 microM and 60 microM with or without co-exposure to TCDD (0.3 nM at maximum). PFOA did not decrease cell viability even at maximum concentrations of 60 microM. TCDD induced CYP1A4 mRNA and EROD activity substantially as reported previously. PFOS also increased CYP1A4 mRNA in a concentration-dependent manner. Co-exposure of cells to PFOS plus TCDD did not change CYP1A4 mRNA levels compared to cells treated with TCDD alone. PFOS alone did not induce CYP4V2 mRNA, however 40-50 microM PFOS plus TCDD (0.3 nM) induced CYP4V2 mRNA compared to TCDD alone (P<0.05). This trend was similar to that observed with co-exposure to TCDD plus PFOA, suggesting that PFOA alone did not induce CYP4V2 mRNA, whereas co-exposure to TCDD plus PFOA induced the expression levels. PFOS alone decreased CYP3A37 mRNA by a maximum of 45%, however after co-exposure to TCDD, recovery of mRNA expression to levels measured in DMSO-treated cells was observed. Our data suggest a complex gene response to mixtures of dioxin-like and perfluorinated compounds.

Chicken embryo cardiomyocyte cultures--a new approach for studying effects of halogenated aromatic hydrocarbons in the avian heart

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), polychlorinated biphenyls (PCBs), and other halogenated aromatic hydrocarbons (HAHs) elicit a variety of adverse biological effects on the cardiovascular systems of mammalian, piscine and avian species. Many of the cardiotoxic effects of HAHs are mediated by the aryl hydrocarbon receptor (AHR). Induction of cytochrome P4501A (CYP1A) is a well-known AHR-dependent response to HAHs in the liver, but there are a limited number of studies on CYP1A induction by these compounds in the heart. We used an in vitro approach to examine effects of TCDD and 3,3',4,4'-tetrachlorobiphenyl (PCB 77) on CYP1A in the avian heart. The responses of primary cultures of chicken embryo cardiomyocytes (CEC) and chicken embryo hepatocytes (CEH) to TCDD and PCB 77 were compared using immunofluorescence staining for CYP1A, the ethoxyresorufin-O-deethylase (EROD) assay, and real-time RT-PCR analysis of CYP1A4 mRNA and CYP1A5 mRNA. Immunofluorescent detection of CYP1A indicated that induction of CYP1A by TCDD was localized within the cytoplasm of CEC cells. EROD activity and CYP1A4/5 mRNA levels were strongly induced in CEC and CEH cultures by TCDD and PCB 77, and the shapes of the concentration-response curves in CEC and CEH cultures were similar. The studies provide clear evidence that the AHR signaling pathway is induced by TCDD and PCB 77 in CEC, and establish a new in vitro approach for studying the effects of HAHs in the avian heart. Induction of CYP1A5 by TCDD in avian cardiomyocytes is a novel finding, and might help direct future studies on mechanisms of action of HAHs in the heart.