The limited utility of electrocardiography variables used to predict arrhythmia in psychotropic drug overdose

OBJECTIVE: The aim of the present study was to examine the relationship between serious arrhythmias in patients with psychotropic drug overdose and electrocardiography (ECG) findings that have been suggested previously to predict this complication. METHODS: Thirty-nine patients with serious arrhythmias (ventricular tachycardia, supraventricular tachycardia or cardiac arrest) after tricyclic antidepressant overdose or thioridazine overdose were compared with 117 controls with clinically significant overdose matched to each case for the drug ingested. These patients with psychotropic drug overdose had presented for treatment to the Department of Clinical Toxicology, Newcastle and to the Princess Alexandra Hospital, Brisbane. The heart rate, the QRS width, the QTc and QT intervals, the QT dispersion, and the R wave and R/S ratios in aVR on the initial ECGs were compared in cases and controls. RESULTS: The cases had taken dothiepin (16 patients), doxepin (six patients), thioridazine (five patients), amitriptyline (five patients), nortriptyline (three patients), imipramine (one patient) and a combination of dothiepin and thioridazine (three patients). In 20 of the 39 patients with arrhythmias, the arrhythmia had been a presumed ventricular tachycardia. Of the other 19 patients, 15 patients had a supraventricular tachycardia, two patients had cardiac arrests (one asystole, one without ECG monitoring) and two patients had insufficient data recorded to make classification of the arrhythmias possible. The QRS was ≥ 100 ms in 82% of cases but also in 76% of controls. QRS ≥ 160 ms had a sensitivity of only 13% and occurred in 2% of controls. QRS > 120 ms, QTc > 500 and the R/S ratio in aVR appeared to have a stronger association with the occurrence of arrhythmia: QRS > 120 ms (odds ratio [OR], 3.56; 95% confidence interval [CI], 1.46–8.68), QTc > 500 (OR, 3.07; 95% CI, 1.33–7.07), and R/S ratio in aVR > 0.7 (OR, 16; 95% CI, 3.47–74). Excluding thioridazine overdoses and performing the analysis for tricyclic antidepressant overdoses alone gave increased odds ratios for QRS > 120 ms (OR, 4.83; 95% CI, 1.73–13.5) and QTc > 500 (OR, 4.5; 95% CI, 1.56–13) but had little effect on that for the R/S ratio in aVR > 0.7 (OR, 14.5; 95% CI, 3.10–68). CONCLUSION: ECG measurements were generally weakly related to the occurrence of arrhythmia and should not be used as the sole criteria for risk assessment in tricyclic antidepressant overdose. The frequently recommended practice of using either QRS ≥ 100 ms or QRS ≥ 160 ms to predict arrhythmias is not supported by our study. R/S ratio in aVR > 0.7 was most strongly related to arrhythmia but had estimated positive and negative predictive values of only 41% and 95%, respectively. The use of these specific predictors in other drug overdoses is not recommended without specific studies

Recent changes in summer distribution and numbers of migratory caribou on the southern Hudson Bay coast

The status of migratory woodland caribou inhabiting the coastal region in southern Hudson Bay is dynamic. The Pen Islands Herd within that region was defined in the 1990s, but opportunistic observations between 1999 and 2007 suggested that its status had significantly changed since the late 1980s and early 1990s. We undertook systematic surveys from the Hayes River, MB, to the Lakitusaki River, ON, in 2008 and 2009 to determine current distribution and minimum numbers of woodland caribou on the southern Hudson Bay coast from the Hayes River, Manitoba, to the Lakitusaki River, Ontario. We documented a significant change in summer distribution during the historical peak aggregation period (7-15 July) compared to the 1990s. In 2008 and 2009, respectively, we tallied 3529 and 3304 animals; however, fewer than 180 caribou were observed each year in the Pen Islands Herd’s former summer range where over 10 798 caribou were observed during a systematic survey in 1994. Over 80% of caribou were in the Cape Henrietta Maria area of Ontario. Calf proportions in herds varied from 8% of animals in the west to 20% in the east. Our 2008 and 2009 systematic surveys were focused on the immediate coast, but one exploratory flight inland suggested that more caribou may be inland than had been observed in the 1980s-1990s. The causes of change in the numbers and distribution in the coastal Hudson Bay Lowlands and the association of current caribou with the formerly large Pen Islands Herd may be difficult to determine because of gaps in monitoring, but satellite telemetry, genetic sampling, remote sensing, habitat analysis, and aboriginal knowledge are all being used to pursue answers

Predicting asthma-related crisis events using routine electronic healthcare data

Background There is no published algorithm predicting asthma crisis events (accident and emergency [A&E] attendance, hospitalisation, or death) using routinely available electronic health record (EHR) data. Aim To develop an algorithm to identify individuals at high risk of an asthma crisis event. Design and setting Database analysis from primary care EHRs of people with asthma across England and Scotland. Method Multivariable logistic regression was applied to a dataset of 61 861 people with asthma from England and Scotland using the Clinical Practice Research Datalink. External validation was performed using the Secure Anonymised Information Linkage Databank of 174 240 patients from Wales. Outcomes were ≥1 hospitalisation (development dataset) and asthma-related hospitalisation, A&E attendance, or death (validation dataset) within a 12-month period. Results Risk factors for asthma-related crisis events included previous hospitalisation, older age, underweight, smoking, and blood eosinophilia. The prediction algorithm had acceptable predictive ability with a receiver operating characteristic of 0.71 (95% confidence interval [CI] = 0.70 to 0.72) in the validation dataset. Using a cut-point based on the 7% of the population at greatest risk results in a positive predictive value of 5.7% (95% CI = 5.3% to 6.1%) and a negative predictive value of 98.9% (95% CI = 98.9% to 99.0%), with sensitivity of 28.5% (95% CI = 26.7% to 30.3%) and specificity of 93.3% (95% CI = 93.2% to 93.4%); those individuals had an event risk of 6.0% compared with 1.1% for the remaining population. In total, 18 people would need to be followed to identify one admission. Conclusion This externally validated algorithm has acceptable predictive ability for identifying patients at high risk of asthma-related crisis events and excluding those not at high risk

Success Factors for Water Safety Plan Implementation in Small Drinking Water Supplies in Low- and Middle-Income Countries

Water Safety Plan (WSP) implementation has the potential to greatly improve, commonly very challenging and resource limited, small drinking water supplies. Although slower than in urban or high-income settings, the uptake of WSPs in low- and middle-income countries (LMICs) is accelerating. Understanding the factors which will make a WSP successful will further improve efficient uptake and assist with its long-term sustainability. Based on an extensive literature search using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISM-A) methodology, 48 publications, including case studies and guidance documentation, formed the basis of this review. These were analysed using inductive and deductive coding methods to (i) identify the success factors applicable to WSP implementation in small drinking water supplies in LMICs and (ii) to investigate which factors are more or less critical depending on the geography and level of development of the implementing country. Key challenges identified during the review process were also noted. A comparison of these success factors was made with those identified from high-income and urban settings. The three most important success factors identified are the development of technical capacity, community engagement, and monitoring and verification. Factors specific to small drinking water supplies in LMICs include support from non-government organisations, integration into existing water sanitation and hygiene (WASH) programs, simplicity, and community engagement. Certain factors, such as adaptability, the use of guidance documentation, international collaboration, the role of pilot studies, knowledge sharing, and stakeholder involvement are applicable to all WSP settings. Due to the specific challenges faced by small drinking water systems and the limited number of original research publications on this topic, this study highlights the need for further data collection and research focused on success factors in these settings. It is anticipated that the consideration of the success factors identified in this study will assist implementers in improving the uptake and long-term sustainability of WSPs in small drinking water supplies in low- and middle-income settings

Protocol for a pragmatic randomised controlled trial of Body Brain Life-General Practice and a Lifestyle Modification Programme to decrease dementia risk exposure in a primary care setting

Introduction It has been estimated that a 10%-25% reduction in seven key risk factors could potentially prevent 1.1-3.0 million Alzheimer's disease cases globally. In addition, as dementia is preceded by more subtle cognitive deficits which have substantial social and economic impact, effective preventative interventions would likely have more extensive benefits. The current study evaluates in primary care a multidomain risk-reduction intervention targeting adults with high risk of developing dementia. Methods and analysis A randomised controlled trial (RCT) is being conducted to evaluate three intervention programmes using a pragmatic approach suitable to the clinic: (1) a 12-week online and face-To-face dementia risk-reduction intervention (Body Brain Life-General Practice (BBL-GP)); (2) a 6-week face-To-face group lifestyle modification programme (LMP); and (3) a 12-week email-only programme providing general health information. We aim to recruit 240 participants, aged 18 and over, to undergo a comprehensive cognitive and physical assessment at baseline and follow-ups (postintervention, 18, 36 and 62 weeks). The primary outcome is dementia risk measured with the modified version of the Australian National University-Alzheimer's Disease Risk Index Short Form. Secondary outcomes are cognitive function measured with Trails A and B, and the Digit Symbol Modalities Test; physical activity with moderate-vigorous physical activity and the International Physical Activity Questionnaire; depression with the Centre for Epidemiological Studies Depression; cost evaluation with the 12-item Short Form Health Survey, Framingham Coronary Heart Disease Risk Score and Australian Type 2 Diabetes Risk Assessment Tool; diet quality with the Australian Recommended Food Score; and sleep quality with the Pittsburgh Sleep Quality Index. Ethics and dissemination This RCT is a novel pragmatic intervention applied in a primary care setting to reduce the dementia risk exposure in adults at high risk. If successful, BBL-GP and LMP will provide a versatile, evidence-based package that can be easily and quickly rolled out to other primary care settings and which can be scaled up at relatively low cost compared with other strategies involving intensive interventions. Trial registration number ACTRN12616000868482This work was supported by National Health and Medical Research Council (NHMRC) Centre of Research Excellence in Cognitive Health and the development of original BBL modules was funded by the NHMRC Dementia Collaborative Research Centres. KJA is funded by NHMRC Fellowship APP1102694

Protocol for a pragmatic randomised controlled trial of Body Brain Life-General Practice and a Lifestyle Modification Programme to decrease dementia risk exposure in a primary care setting

INTRODUCTION: It has been estimated that a 10%-25% reduction in seven key risk factors could potentially prevent 1.1-3.0 million Alzheimer\u27s disease cases globally. In addition, as dementia is preceded by more subtle cognitive deficits which have substantial social and economic impact, effective preventative interventions would likely have more extensive benefits. The current study evaluates in primary care a multidomain risk-reduction intervention targeting adults with high risk of developing dementia. METHODS AND ANALYSIS: A randomised controlled trial (RCT) is being conducted to evaluate three intervention programmes using a pragmatic approach suitable to the clinic: (1) a 12-week online and face-to-face dementia risk-reduction intervention (Body Brain Life-General Practice (BBL-GP)); (2) a 6-week face-to-face group lifestyle modification programme (LMP); and (3) a 12-week email-only programme providing general health information. We aim to recruit 240 participants, aged 18 and over, to undergo a comprehensive cognitive and physical assessment at baseline and follow-ups (postintervention, 18, 36 and 62 weeks). The primary outcome is dementia risk measured with the modified version of the Australian National University-Alzheimer\u27s Disease Risk Index Short Form. Secondary outcomes are cognitive function measured with Trails A and B, and the Digit Symbol Modalities Test; physical activity with moderate-vigorous physical activity and the International Physical Activity Questionnaire; depression with the Centre for Epidemiological Studies Depression; cost evaluation with the 12-item Short Form Health Survey, Framingham Coronary Heart Disease Risk Score and Australian Type 2 Diabetes Risk Assessment Tool; diet quality with the Australian Recommended Food Score; and sleep quality with the Pittsburgh Sleep Quality Index. ETHICS AND DISSEMINATION: This RCT is a novel pragmatic intervention applied in a primary care setting to reduce the dementia risk exposure in adults at high risk. If successful, BBL-GP and LMP will provide a versatile, evidence-based package that can be easily and quickly rolled out to other primary care settings and which can be scaled up at relatively low cost compared with other strategies involving intensive interventions.&nbsp

Broadly neutralizing antibody responses in a large longitudinal sub-Saharan HIV primary infection cohort

Author Summary Understanding how HIV-1-broadly neutralizing antibodies (bnAbs) develop during natural infection is essential to the design of an efficient HIV vaccine. We studied kinetics and correlates of neutralization breadth in a large sub-Saharan African longitudinal cohort of 439 participants with primary HIV-1 infection. Broadly nAb responses developed in 15% of individuals, on average three years after infection. Broad neutralization was associated with high viral load, low CD4+ T cell counts, virus subtype C infection and HLA*A3(-) genotype. A correlation with high overall plasma IgG levels and anti-Env binding titers was also found. Specificity mapping of the bnAb responses showed that glycan-dependent epitopes, in particular the N332 region, were most commonly targeted, in contrast to other bnAb epitopes, suggesting that the HIV Env N332-glycan epitope region may be a favorable target for vaccine design

Recommendations on data sharing in HIV drug resistance research

• Human immunodeficiency virus (HIV) drug resistance has implications for antiretroviral treatment strategies and for containing the HIV pandemic because the development of HIV drug resistance leads to the requirement for antiretroviral drugs that may be less effective, less well-tolerated, and more expensive than those used in first-line regimens.  • HIV drug resistance studies are designed to determine which HIV mutations are selected by antiretroviral drugs and, in turn, how these mutations affect antiretroviral drug susceptibility and response to future antiretroviral treatment regimens.  • Such studies collectively form a vital knowledge base essential for monitoring global HIV drug resistance trends, interpreting HIV genotypic tests, and updating HIV treatment guidelines.  • Although HIV drug resistance data are collected in many studies, such data are often not publicly shared, prompting the need to recommend best practices to encourage and standardize HIV drug resistance data sharing.  • In contrast to other viruses, sharing HIV sequences from phylogenetic studies of transmission dynamics requires additional precautions as HIV transmission is criminalized in many countries and regions.  • Our recommendations are designed to ensure that the data that contribute to HIV drug resistance knowledge will be available without undue hardship to those publishing HIV drug resistance studies and without risk to people living with HIV

HIV-1 infected monozygotic twins: a tale of two outcomes

<p>Abstract</p> <p>Background</p> <p>Replicate experiments are often difficult to find in evolutionary biology, as this field is inherently an historical science. However, viruses, bacteria and phages provide opportunities to study evolution in both natural and experimental contexts, due to their accelerated rates of evolution and short generation times. Here we investigate HIV-1 evolution by using a natural model represented by monozygotic twins infected synchronically at birth with an HIV-1 population from a shared blood transfusion source. We explore the evolutionary processes and population dynamics that shape viral diversity of HIV in these monozygotic twins.</p> <p>Results</p> <p>Despite the identical host genetic backdrop of monozygotic twins and the identical source and timing of the HIV-1 inoculation, the resulting HIV populations differed in genetic diversity, growth rate, recombination rate, and selection pressure between the two infected twins.</p> <p>Conclusions</p> <p>Our study shows that the outcome of evolution is strikingly different between these two "replicates" of viral evolution. Given the identical starting points at infection, our results support the impact of random epigenetic selection in early infection dynamics. Our data also emphasize the need for a better understanding of the impact of host-virus interactions in viral evolution.</p

Fibroblast Growth Factor Receptor Signaling Dramatically Accelerates Tumorigenesis and Enhances Oncoprotein Translation in the Mouse Mammary Tumor Virus-Wnt-1 Mouse Model of Breast Cancer

Fibroblast growth factor (FGF) cooperates with the Wnt/β-catenin pathway to promote mammary tumorigenesis. To investigate the mechanisms involved in FGF/Wnt cooperation, we genetically engineered a model of inducible FGF receptor (iFGFR) signaling in the context of the well-established mouse mammary tumor virus–Wnt-1 transgenic mouse. In the bigenic mice, iFGFR1 activation dramatically enhanced mammary tumorigenesis. Expression microarray analysis did not show transcriptional enhancement of Wnt/β-catenin target genes but instead showed a translational gene signature that also correlated with elevated FGFR1 and FGFR2 in human breast cancer data sets. Additionally, iFGFR1 activation enhanced recruitment of RNA to polysomes, resulting in a marked increase in protein expression of several different Wnt/β-catenin target genes. FGF pathway activation stimulated extracellular signal-regulated kinase and the phosphorylation of key translation regulators both in vivo in the mouse model and in vitro in a human breast cancer cell line. Our results suggest that cooperation of the FGF and Wnt pathways in mammary tumorigenesis is based on the activation of protein translational pathways that result in, but are not limited to, increased expression of Wnt/β-catenin target genes (at the level of protein translation). Further, they reveal protein translation initiation factors as potential therapeutic targets for human breast cancers with alterations in FGF signaling