Implementation Evaluation of a Complex Intervention to Improve Timeliness of Care for Veterans with Transient Ischemic Attack.

BACKGROUND: The Protocol-guided Rapid Evaluation of Veterans Experiencing New Transient Neurologic Symptoms (PREVENT) program was designed to address systemic barriers to providing timely guideline-concordant care for patients with transient ischemic attack (TIA). OBJECTIVE: We evaluated an implementation bundle used to promote local adaptation and adoption of a multi-component, complex quality improvement (QI) intervention to improve the quality of TIA care Bravata et al. (BMC Neurology 19:294, 2019). DESIGN: A stepped-wedge implementation trial with six geographically diverse sites. PARTICIPANTS: The six facility QI teams were multi-disciplinary, clinical staff. INTERVENTIONS: PREVENT employed a bundle of key implementation strategies: team activation; external facilitation; and a community of practice. This strategy bundle had direct ties to four constructs from the Consolidated Framework for Implementation Research (CFIR): Champions, Reflecting & Evaluating, Planning, and Goals & Feedback. MAIN MEASURES: Using a mixed-methods approach guided by the CFIR and data matrix analyses, we evaluated the degree to which implementation success and clinical improvement were associated with implementation strategies. The primary outcomes were the number of completed implementation activities, the level of team organization and > 15 points improvement in the Without Fail Rate (WFR) over 1 year. KEY RESULTS: Facility QI teams actively engaged in the implementation strategies with high utilization. Facilities with the greatest implementation success were those with central champions whose teams engaged in planning and goal setting, and regularly reflected upon their quality data and evaluated their progress against their QI plan. The strong presence of effective champions acted as a pre-condition for the strong presence of Reflecting & Evaluating, Goals & Feedback, and Planning (rather than the other way around), helping to explain how champions at the +2 level influenced ongoing implementation. CONCLUSIONS: The CFIR-guided bundle of implementation strategies facilitated the local implementation of the PREVENT QI program and was associated with clinical improvement in the national VA healthcare system. TRIAL REGISTRATION: clinicaltrials.gov: NCT02769338.

When is a randomised controlled trial health equity relevant? Development and validation of a conceptual framework.

BACKGROUND: Randomised controlled trials can provide evidence relevant to assessing the equity impact of an intervention, but such information is often poorly reported. We describe a conceptual framework to identify health equity-relevant randomised trials with the aim of improving the design and reporting of such trials. METHODS: An interdisciplinary and international research team engaged in an iterative consensus building process to develop and refine the conceptual framework via face-to-face meetings, teleconferences and email correspondence, including findings from a validation exercise whereby two independent reviewers used the emerging framework to classify a sample of randomised trials. RESULTS: A randomised trial can usefully be classified as 'health equity relevant' if it assesses the effects of an intervention on the health or its determinants of either individuals or a population who experience ill health due to disadvantage defined across one or more social determinants of health. Health equity-relevant randomised trials can either exclusively focus on a single population or collect data potentially useful for assessing differential effects of the intervention across multiple populations experiencing different levels or types of social disadvantage. Trials that are not classified as 'health equity relevant' may nevertheless provide information that is indirectly relevant to assessing equity impact, including information about individual level variation unrelated to social disadvantage and potentially useful in secondary modelling studies. CONCLUSION: The conceptual framework may be used to design and report randomised trials. The framework could also be used for other study designs to contribute to the evidence base for improved health equity.

Watershed influences on the structure and function of riparian wetlands associated with headwater streams - Kenai Peninsula, Alaska.

Riparian wetlands are dynamic components of landscapes. Located between uplands and aquatic environments, riparian habitats intercept sediments and nutrients before they enter aquatic environments. They are a source of organic matter and nutrients to aquatic systems, and they provide important habitat for animals, often serving as corridors for the movement of animals between habitats in fragmented landscapes. In this project, we focused on the structure and function of riparian wetlands associated with headwater streams in Alaska that serve as nursery habitats for juvenile salmonids. We asked whether or not the structure and function of headwater wetlands differed between watersheds with and without nitrogen-fixing Alder (Alnus spp.). We found that the aboveground biomass of riparian vegetation was higher in the watershed with Alder, but the largest differences were in the litter layer and belowground where vegetation in the watershed with no Alder had significantly higher root biomass. Interstitial water chemistry also differed between the study sites with significantly higher inorganic N and significantly different characteristics of colored dissolved organic matter at the site with Alder on the watershed. The biomass of litter that hung over the creek bank was less at the site with Alder on the watershed and an in situ decomposition experiment showed significant differences between the two systems. Results of the research demonstrates that watershed characteristics can impact the ecology of headwater streams in ways that had not been previously recognized.

The association between adverse childhood experiences (ACEs) and suicide attempts in a population-based study.

OBJECTIVES: To further our understanding of the relationship between Adverse Childhood Experiences (ACEs) and suicidal behaviour, this study investigates the association between three types of ACEs and lifetime suicide attempts, while considering potential gender-specific and mediating effects. METHODS: Data were obtained from the 2012 Canadian Community Health Survey-Mental Health (CCHS-MH), a cross-sectional, population-based survey comprised of respondents aged 18 or older who provided self-reported data on past experiences of suicide attempts, as well as childhood sexual abuse (CSA), childhood physical abuse (CPA) and parental domestic violence (PDV) (n = 22 559). After testing for ACE by gender interactions, we estimated the odds of lifetime suicide attempts for each ACE and then investigated whether depression, anxiety, substance abuse and chronic pain acted as mediators of the relationship. RESULTS: The odds of suicide attempts are significantly higher among those with a history of CPA (OR = 3.29; 99.9% CI 2.33-4.64), CSA (OR = 4.42; 99.9% CI 3.14-6.23) or PDV (OR = 2.52; 99.9% CI 1.69-3.76), when ACEs are mutually adjusted. There is little evidence that gender acts as a moderator; however, depression, anxiety, substance abuse and chronic pain appear to partially mediate the associations. Depression alone accounts for about a quarter of the associations with CSA and CPA. CONCLUSIONS: Mental health factors and chronic pain appear only to partially mediate relationships between ACEs and lifetime suicide attempts. Future research should look at other pathways with the goal of developing multi-level interventions.

Genetic distinction between contiguous urban and rural multimammate mice in Tanzania despite gene flow.

Special conditions are required for genetic differentiation to arise at a local geographical scale in the face of gene flow. The Natal multimammate mouse, Mastomys natalensis, is the most widely distributed and abundant rodent in sub-Saharan Africa. A notorious agricultural pest and a natural host for many zoonotic diseases, it can live in close proximity to humans and appears to compete with other rodents for the synanthropic niche. We surveyed its population genetic structure across a 180-km transect in central Tanzania along which the landscape varied between agricultural land in a rural setting and natural woody vegetation, rivers, roads and a city (Morogoro). We sampled M. natalensis across 10 localities and genotyped 15 microsatellite loci from 515 individuals. Hierarchical STRUCTURE analyses show a K-invariant pattern distinguishing Morogoro suburbs (located in the centre of the transect) from nine surrounding rural localities. Landscape connectivity analyses in Circuitscape and comparison of rainfall patterns suggest that neither geographical isolation nor natural breeding asynchrony could explain the genetic differentiation of the urban population. Using the isolation-with-migration model implemented in IMa2, we inferred that a split between suburban and rural populations would have occurred recently (<150 years ago) with higher urban effective population density consistent with an urban source to rural sink of effective migration. The observed genetic differentiation of urban multimammate mice is striking given the uninterrupted distribution of the animal throughout the landscape and the high estimates of effective migration (2Ne M = 3.0 and 29.7), suggesting a strong selection gradient across the urban boundary.

Occidiofungin is an important component responsible for the antifungal activity of Burkholderia pyrrocinia strain Lyc2.

AIMS: To identify the taxonomy of tobacco rhizosphere-isolated strain Lyc2 and investigate the mechanisms of the antifungal activities, focusing on antimicrobials gene clusters identification and function analysis. METHODS AND RESULTS: Multilocus sequence typing and 16S rRNA analyses indicated that strain Lyc2 belongs to Burkholderia pyrrocinia. Bioassay results indicated strain Lyc2 showed significant antifungal activities against a broad range of plant and animal fungal pathogens and control efficacy on seedling damping off disease of cotton. A 55·2-kb gene cluster which was homologous to ocf gene clusters in Burkholderia contaminans MS14 was confirmed to be responsible for antifungal activities by random mutagenesis; HPLC was used to verify the production of antifungal compounds. Multiple antibiotic and secondary metabolized biosynthesis gene clusters predicated by antiSMASH revealed the broad spectrum of antimicrobials activities of the strain. CONCLUSIONS: Our results revealed the mechanisms of antifungal activities of strain Lyc2 and expand our knowledge about production of occidiofungin in the bacteria Burkholderia. SIGNIFICANCE AND IMPACT OF THE STUDY: Understanding the mechanisms of antifungal activities of strain Lyc2 has contributed to discovery of new antibiotics and expand our knowledge of production of occidiofungin in the bacteria Burkholderia.

Hexokinase 2 controls cellular stress response through localization of an RNA-binding protein.

Subcellular localization of RNA-binding proteins is a key determinant of their ability to control RNA metabolism and cellular stress response. Using an RNAi-based kinome-wide screen, we identified hexokinase 2 (HK2) as a regulator of the cytoplasmic accumulation of hnRNP A1 in response to hypertonic stress and human rhinovirus infection (HRV). We show that inhibition of HK2 expression or pharmacological inhibition of HK2 activity blocks the cytoplasmic accumulation of heterogeneous nuclear ribonucleoprotein A1 (hnRNP A1), restores expression of B-cell lymphoma-extra large (Bcl-xL), and protects cells against hypertonic stress-induced apoptosis. Reduction of HK2 protein levels by knockdown results in decreased HRV replication, a delay in HRV-induced cell death, and a reduced number of infected cells, all of which can be rescued by forced expression of a cytoplasm-restricted hnRNP A1. Our data elucidate a novel role for HK2 in cellular stress response and viral infection that could be exploited for therapeutic intervention.

Hybridization and speciation.

Hybridization has many and varied impacts on the process of speciation. Hybridization may slow or reverse differentiation by allowing gene flow and recombination. It may accelerate speciation via adaptive introgression or cause near-instantaneous speciation by allopolyploidization. It may have multiple effects at different stages and in different spatial contexts within a single speciation event. We offer a perspective on the context and evolutionary significance of hybridization during speciation, highlighting issues of current interest and debate. In secondary contact zones, it is uncertain if barriers to gene flow will be strengthened or broken down due to recombination and gene flow. Theory and empirical evidence suggest the latter is more likely, except within and around strongly selected genomic regions. Hybridization may contribute to speciation through the formation of new hybrid taxa, whereas introgression of a few loci may promote adaptive divergence and so facilitate speciation. Gene regulatory networks, epigenetic effects and the evolution of selfish genetic material in the genome suggest that the Dobzhansky-Muller model of hybrid incompatibilities requires a broader interpretation. Finally, although the incidence of reinforcement remains uncertain, this and other interactions in areas of sympatry may have knock-on effects on speciation both within and outside regions of hybridization.

Cluster of non-tuberculous mycobacteraemia associated with water supply in a haemato-oncology unit.

Non-tuberculous mycobacteria (NTM) are ubiquitous environmental organisms but rarely cause infections. Clinical, microbiological and epidemiological investigations and subsequent management of a cluster of NTM bacteraemia on a haemato-oncology unit are reported. From October 2007 to July 2008, five patients being managed for haematological malignancies developed pyrexia and general malaise. Mycobacterium mucogenicum (four patients) and Mycobacterium neoaurum (one patient) were identified from their blood cultures. The environment, in particular the water system, was investigated to identify the source of the infection and multiple water samples were cultured according to established criteria. NTM were also isolated from the hospital water system. Central venous catheters (CVCs) were removed and the patients were successfully treated with antibiotics. Environmental measures and changes in CVC care were introduced to prevent further episodes of NTM bacteraemia in these patients. Despite these measures, NTM continued to be present in the water system, but new clinical cases were not identified. NTM are common environmental organisms and are recognized as being difficult to remove from water systems. CVCs were presumed to be the portal of entry in this cluster of NTM bacteraemia, and the implementation of changes to CVC care protocols was successful in preventing further infections in this immunocompromised patient group.

SMG1 and NIK regulate apoptosis induced by Smac mimetic compounds.

Smac mimetic compounds (SMCs) are experimental small molecules that induce tumour necrosis factor alpha (TNFα)-dependent cancer cell death by targeting the inhibitor of apoptosis proteins. However, many cancer cell lines are resistant to SMC-mediated apoptosis despite the presence of TNFα. To add insight into the mechanism of SMC-resistance, we used functional siRNA-based kinomic and focused chemical screens and identified suppressor of morphogenesis in genitalia-1 (SMG1) and NF-κB-inducing kinase (NIK) as novel protective factors. Both SMG1 and NIK prevent SMC-mediated apoptosis likely by maintaining FLICE inhibitory protein (c-FLIP) levels to suppress caspase-8 activation. In SMC-resistant cells, the accumulation of NIK upon SMC treatment enhanced the activity of both the classical and alternative nuclear factor-κB pathways, and increased c-FLIP mRNA levels. In parallel, persistent SMG1 expression in SMC-resistant cells repressed SMC-mediated TNFα-induced JNK activation and c-FLIP levels were sustained. Importantly, SMC-resistance is overcome by depleting NIK and SMG1, which appear to facilitate the downregulation of c-FLIP in response to SMC and TNFα treatment, leading to caspase-8-dependent apoptosis. Collectively, these data show that SMG1 and NIK function as critical repressors of SMC-mediated apoptosis by potentially converging on the regulation of c-FLIP metabolism.

Genetic structure and contrasting selection pattern at two major histocompatibility complex genes in wild house mouse populations.

The mammalian major histocompatibility complex (MHC) is a tightly linked cluster of immune genes, and is often thought of as inherited as a unit. This has led to the hope that studying a single MHC gene will reveal patterns of evolution representative of the MHC as a whole. In this study we analyse a 1000-km transect of MHC variation traversing the European house mouse hybrid zone to compare signals of selection and patterns of diversification at two closely linked MHC class II genes, H-2Aa and H-2Eb. We show that although they are 0.01 cM apart (that is, recombination is expected only once in 10 000 meioses), disparate evolutionary patterns were detected. H-2Aa shows higher allelic polymorphism, faster allelic turnover due to higher mutation rates, stronger positive selection at antigen-binding sites and higher population structuring than H-2Eb. H-2Eb alleles are maintained in the gene pool for longer, including over separation of the subspecies, some H-2Eb alleles are positively and others negatively selected and some of the alleles are not expressed. We conclude that studies on MHC genes in wild-living vertebrates can give substantially different results depending on the MHC gene examined and that the level of polymorphism in a related species is a poor criterion for gene choice.

Low-dose paclitaxel synergizes with oncolytic adenoviruses via mitotic slippage and apoptosis in ovarian cancer.

The microtubule-stabilizing drug paclitaxel has activity in relapsed ovarian cancer. dl922-947, an oncolytic adenovirus with a 24-bp deletion in E1A CR2, replicates selectively within and lyses cells with a dysregulated Rb pathway and has efficacy in ovarian cancer. In the aggressive A2780CP xenograft, combination treatment with weekly dl922-947 and paclitaxel has significantly greater efficacy than either treatment alone and can produce complete tumor eradication in some animals. We investigated the mechanisms of paclitaxel's synergy with dl922-947 in ovarian cancer. The host-cell microtubule network is grossly rearranged and stabilized following adenovirus infection, but paclitaxel does not increase this significantly. Paclitaxel does not synergize by increasing infectivity, viral protein expression or virus release. However, destabilizing the microtubule network with nocodazole reduces viral exit, revealing a novel microtubule-dependent pathway for non-lytic adenoviral exit. dl922-947 can override multiple cell cycle checkpoints but induces cell death by a non-apoptotic mechanism. In combination, dl922-947 and low-dose paclitaxel induces aberrant, multipolar mitoses, mitotic slippage and multinucleation, triggering an apoptotic cell death.

NF45 functions as an IRES trans-acting factor that is required for translation of cIAP1 during the unfolded protein response.

Expression of the cellular inhibitor of apoptosis protein 1 (cIAP1) is unexpectedly repressed at the level of translation under normal physiological conditions in many cell lines. We have previously shown that the 5' untranslated region of cIAP1 mRNA contains a stress-inducible internal ribosome entry site (IRES) that governs expression of cIAP1 protein. Although inactive in unstressed cells, the IRES supports cap-independent translation of cIAP1 in response to endoplasmic reticulum stress. To gain an insight into the mechanism of cIAP1 IRES function, we empirically derived the minimal free energy secondary structure of the cIAP1 IRES using enzymatic cleavage mapping. We subsequently used RNA affinity chromatography to identify several cellular proteins, including nuclear factor 45 (NF45) as cIAP1 IRES binding proteins. In this report we show that NF45 is a novel RNA binding protein that enhances IRES-dependent translation of endogenous cIAP1. Further, we show that NF45 is required for IRES-mediated induction of cIAP1 protein during the unfolded protein response. The data presented are consistent with a model in which translation of cIAP1 is governed, at least in part, by NF45, a novel cellular IRES trans-acting factor.

IAP-targeted therapies for cancer.

DNA damage, chromosomal abnormalities, oncogene activation, viral infection, substrate detachment and hypoxia can all trigger apoptosis in normal cells. However, cancer cells acquire mutations that allow them to survive these threats that are part and parcel of the transformation process or that may affect the growth and dissemination of the tumor. Eventually, cancer cells accumulate further mutations that make them resistant to apoptosis mediated by standard cytotoxic chemotherapy or radiotherapy. The inhibitor of apoptosis (IAP) family members, defined by the presence of a baculovirus IAP repeat (BIR) protein domain, are key regulators of cytokinesis, apoptosis and signal transduction. Specific IAPs regulate either cell division, caspase activity or survival pathways mediated through binding to their BIR domains, and/or through their ubiquitin-ligase RING domain activity. These protein-protein interactions and post-translational modifications are the subject of intense investigations that shed light on how these proteins contribute to oncogenesis and resistance to therapy. In the past several years, we have seen multiple approaches of IAP antagonism enter the clinic, and the rewards of such strategies are about to reap benefit. Significantly, small molecule pan-IAP antagonists that mimic an endogenous inhibitor of the IAPs, called Smac, have demonstrated an unexpected ability to sensitize cancer cells to tumor necrosis factor-alpha and to promote autocrine or paracrine production of this cytokine by the tumor cell and possibly, other cells too. This review will focus on these and other developmental therapeutics that target the IAPs in cancer.

Oncolytic adenoviral mutants induce a novel mode of programmed cell death in ovarian cancer.

Oncolytic adenoviral mutants have considerable activity in ovarian cancer. However, the mechanisms by which they induce cell death remain uncertain. dl922-947, which contains a 24 bp deletion in E1A CR2, is more potent than both E1A wild-type adenoviruses and the E1B-55K deletion mutant dl1520 (Onyx-015). We investigated the mode of death induced by three E1A CR2-deleted replicating adenoviruses in models of ovarian cancer and also the importance of E3 11.6 (adenovirus death protein) in determining this mode of death. Ovarian cancer cells were infected with dl922-947 (E3 11.6+) and dlCR2 (E3 11.6-). We also generated dlCR2 tSmac, which also encodes the gene for processed Smac/DIABLO. Classical apoptosis does not occur in adenoviral cell death and there is no role for mitochondria. Expression of Smac/DIABLO does not enhance cytotoxicity nor increase apoptotic features. A role for cathepsins and lysosomal membrane permeability was excluded. Autophagy is induced, but is not the mode of death and may act as a cell survival mechanism. There is no evidence of pure necrosis, while the presence of E3 11.6 does not modulate the mode or extent of cell death. Thus, E1A CR2-deleted oncolytic adenoviral cytotoxicity in ovarian cancer may define a novel mode of programmed cell death.

The distribution of surviving blocks of an ancestral genome.

What is the chance that some part of a stretch of genome will survive? In a population of constant size, and with no selection, the probability of survival of some part of a stretch of map length y < 1 approaches y/log(yt/2) for log(yt) > or = 1. Thus, the whole genome is certain to be lost, but the rate of loss is extremely slow. This solution extends to give the whole distribution of surviving block sizes as a function of time. We show that the expected number of blocks at time t is 1+yt and give expressions for the moments of the number of blocks and the total amount of genome that survives for a given time. The solution is based on a branching process and assumes complete interference between crossovers, so that each descendant carries only a single block of ancestral material. We consider cases where most individuals carry multiple blocks, either because there are multiple crossovers in a long genetic map, or because enough time has passed that most individuals in the population are related to each other. For species such as ours, which have a long genetic map, the genome of any individual which leaves descendants (approximately 80% of the population for a Poisson offspring number with mean two) is likely to persist for an extremely long time, in the form of a few short blocks of genome.

Randomized comparison of enoxaparin with unfractionated heparin following fibrinolytic therapy for acute myocardial infarction.

AIMS: To compare the efficacy and safety of low molecular weight heparin with unfractionated heparin following fibrinolytic therapy for acute myocardial infarction. METHODS AND RESULTS: Three-hundred patients receiving fibrinolytic therapy following acute myocardial infarction were randomly assigned to low molecular weight heparin as enoxaparin (40 mg intravenous bolus, then 40 mg subcutaneously every 8 h, n=149) or unfractionated heparin (5000 U intravenous bolus, then 30 000 U. 24 h(-1), adjusted to an activated partial thromboplastin time 2-2.5x normal, n=151) for 4 days in conjunction with routine therapy. Clinical and therapeutic variables were analysed, in addition to use of enoxaparin or unfractionated heparin, to determine independent predictors of the 90-day composite triple end-point (death, non-fatal reinfarction, or readmission with unstable angina). The triple end-point occurred more frequently in patients receiving unfractionated heparin rather than enoxaparin (36% vs. 26%; P=0.04). Logistic regression modelling of baseline and clinical variables identified the only independent risk factors for recurrent events as left ventricular failure, hypertension, and use of unfractionated heparin rather than enoxaparin. There was no difference in major haemorrhage between those receiving enoxaparin (3%) and unfractionated heparin (4%). CONCLUSION: Use of enoxaparin compared with unfractionated heparin in patients receiving fibrinolytic therapy for acute myocardial infarction was associated with fewer recurrent cardiac events at 90 days. This benefit was independent of other important clinical and therapeutic factors.

Reproductive and developmental risks from ethylene oxide: a probabilistic characterization of possible regulatory thresholds.

Ethylene oxide is a gas produced in large quantities in the United States that is used primarily as a chemical intermediate in the production of ethylene glycol, propylene glycol, non-ionic surfactants, ethanolamines, glycol ethers, and other chemicals. It has been well established that ethylene oxide can induce cancer, genetic, reproductive and developmental, and acute health effects in animals. The U.S. Environmental Protection Agency is currently developing both a cancer potency factor and a reference concentration (RfC) for ethylene oxide. This study used the rich database on the reproductive and developmental effects of ethylene oxide to develop a probabilistic characterization of possible regulatory thresholds for ethylene oxide. This analysis was based on the standard regulatory approach for noncancer risk assessment, but involved several innovative elements, such as: (1) the use of advanced statistical methods to account for correlations in developmental outcomes among littermates and allow for simultaneous control of covariates (such as litter size); (2) the application of a probabilistic approach for characterizing the uncertainty in extrapolating the animal results to humans; and (3) the use of a quantitative approach to account for the variation in heterogeneity among the human population. This article presents several classes of results, including: (1) probabilistic characterizations of ED10s for two quantal reproductive outcomes-resorption and fetal death, (2) probabilistic characterizations of one developmental outcome-the dose expected to yield a 5% reduction in fetal (or pup) weight, (3) estimates of the RfCs that would result from using these values in the standard regulatory approach for noncancer risk assessment, and (4) a probabilistic characterization of the level of ethylene oxide exposure that would be expected to yield a 1/1,000 increase in the risk of reproductive or developmental outcomes in exposed human populations.