263 research outputs found
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Application of receiver operating characteristic analysis to a remote monitoring model for chronic obstructive pulmonary disease to determine utility and predictive value
This thesis was submitted for the degree of doctor of Philosophy and awarded by Brunel UniversityThis is a foundational study that applies Receiver Operating Characteristic (ROC) analysis to the evaluation of a chronic disease model that utilizes Remote Monitoring (RM) devices to identify clinical deterioration in a Chronic Obstructive Pulmonary Disease (COPD) population.
Background: RM programmes in Disease Management (DM) are proliferating as one strategy to address management of chronic disease. The need to validate and quantify evidence-based value is acute. There is a need to apply new methods to better evaluate automated RM systems. ROC analysis is an engineering approach that has been widely applied to medical programmes but has not been applied to RM systems. Evaluation of classifiers, determination of thresholds and predictive accuracy for RM systems have not been evaluated using ROC analysis. Objectives: (1) apply ROC analysis to evaluation of a RM system; (2) analyse the performance of the model when applied to patient outcomes for a COPD population; (3) identify predictive classifier(s); (4) identify optimal threshold(s) and the predictive capacity of the classifiers.
Methods: Parametric and non-parametric methods are utilized to determine accuracy, sensitivity, specificity and predictive capacity of classifiers Saturated Peripheral Oxygen (SpO2), Blood Pressure (BP), Pulse Rate (PR) based on event-based patient outcomes that include hospitalisation (IP), accident & emergency (A&E) and home visits (HH). Population: Patients identified with a primary diagnosis of COPD, monitored for a minimum of 183 days with at least one episode of in-patient (IP) hospitalisation for COPD in the 12 months preceding the monitoring period. Data Source: A subset of retrospective de-identified patient data from an NHS Direct evaluation of a COPD RM programme. Subsets utilized include classifiers, biometric readings, alerts generated by the system and resource utilisation. Contribution: Validates ROC methodology, identifies classifier performance and optimal threshold settings for the classifier, while making design recommendations and putting forth the next steps for research. The question answered by this research is that ROC analysis can provide additional information on the predictive capacity of RM systems.
Justification of benefit: The results can be applied when evaluating health services and planning decisions on the costs and benefits. Methods can be applied to system design, protocol development, work flows and commissioning decisions based on value and benefit. Conclusion: Results validate the use of ROC analysis as a robust methodology for DM programmes that use RM devices to evaluate classifiers, thresholds and identification of the predictive capacity as well as identify areas where additional design may improve the predictive capacity of the model.
Interventions for Autism Spectrum Disorders: State of the Evidence
The number of children in Maine with Autism Spectrum Disorders (ASD) has increased significantly over the past decade. Since 2000, the number of children receiving Special Education services for ASD in Maine schools jumped from 594 to 2,231in 2008 – an increase of 276%. A recent study estimated that the total cost of caring for a person with autism over his or her lifetime can reach 35 billion spent collectively per year (Ganz, 2007). To conserve already scarce resources and of-fer the best possible services to children with ASD, it is necessary to identify and understand the treat-ments and methods that produce positive outcomes as proven by research. Science helps to clarify some of the confusion about what “works” and enables evidence-informed treatment decisions, thus saving pre-cious time and resources
Treatment algorithm for infants diagnosed with spinal muscular atrophy through newborn screening
Spinal muscular atrophy (SMA) is an autosomal recessive disease characterized by the degeneration of alpha motor neurons in the spinal cord, leading to muscular atrophy. SMA is caused by deletions or mutations in the survival motor neuron 1 gene (SMN1). In humans, a nearly identical copy gene, SMN2, is present. Because SMN2 has been shown to decrease disease severity in a dose-dependent manner, SMN2 copy number is predictive of disease severity.
To develop a treatment algorithm for SMA-positive infants identified through newborn screening based upon SMN2 copy number.
A working group comprised of 15 SMA experts participated in a modified Delphi process, moderated by a neutral third-party expert, to develop treatment guidelines.
The overarching recommendation is that all infants with two or three copies of SMN2 should receive immediate treatment (n = 13). For those infants in which immediate treatment is not recommended, guidelines were developed that outline the timing and appropriate screens and tests to be used to determine the timing of treatment initiation.
The identification SMA affected infants via newborn screening presents an unprecedented opportunity for achievement of maximal therapeutic benefit through the administration of treatment pre-symptomatically. The recommendations provided here are intended to help formulate treatment guidelines for infants who test positive during the newborn screening process
Sustained expansion of NKT cells and antigen-specific T cells after injection of α-galactosyl-ceramide loaded mature dendritic cells in cancer patients
Natural killer T (NKT) cells are distinct glycolipid reactive innate lymphocytes that are implicated in the resistance to pathogens and tumors. Earlier attempts to mobilize NKT cells, specifically, in vivo in humans met with limited success. Here, we evaluated intravenous injection of monocyte-derived mature DCs that were loaded with a synthetic NKT cell ligand, α-galactosyl-ceramide (α-GalCer; KRN-7000) in five patients who had advanced cancer. Injection of α-GalCer–pulsed, but not unpulsed, dendritic cells (DCs) led to >100-fold expansion of several subsets of NKT cells in all patients; these could be detected for up to 6 mo after vaccination. NKT activation was associated with an increase in serum levels of interleukin-12 p40 and IFN-γ inducible protein-10. In addition, there was an increase in memory CD8(+) T cells specific for cytomegalovirus in vivo in response to α-GalCer–loaded DCs, but not unpulsed DCs. These data demonstrate the feasibility of sustained expansion of NKT cells in vivo in humans, including patients who have advanced cancer, and suggest that NKT activation might help to boost adaptive T cell immunity in vivo
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A springtime source of toxic Pseudo-nitzschia cells on razor clam beaches in the Pacific Northwest
Concentrations of domoic acid (DA) above the regulatory limit in Washington coast razor clams are usually higher on northern beaches from summer to fall. Recent field studies have confirmed that the primary source of toxic Pseudo-nitzschia (PN) cells in those seasons is a semi-retentive topographically trapped seasonal eddy located offshore and north of the clamming beaches. Another semi-retentive coastal feature, Heceta Bank, that has been shown to support toxic PN cells in summer, is located south of Washington's clamming beaches. In this paper we present evidence to demonstrate that Heceta Bank, although not a likely source of toxic cells to Washington in summer due to the prevailing southward seasonal currents, may be a source of cells in springtime before the southward currents develop. In contrast to summer and fall seasons, concentrations of DA in razor clams are typically higher at southern beaches in spring. The likelihood of a southern source is explored using biological and transport data surrounding a period of toxic razor clams in April 2005. In particular, satellite-derived chlorophyll data confirm that a bloom occurred over Heceta Bank in March of that year, just prior to a period of strong storm-driven northward transport. PN cells of the same species observed in the April bloom on Washington beaches and in offshore waters were documented in Oregon offshore waters on the northern edge of Heceta Bank. That species, P. australis, has been shown to be highly toxic in this region; shore-based data show that razor clams on Oregon beaches were also toxic at the time when P. australis was observed offshore. Both measured and modeled currents show that transport was more than sufficient to move cells from the vicinity of Heceta Bank, Oregon to southern Washington beaches by the time the toxic cells were observed on those beaches. The rapid transport was due in part to the presence of the buoyant plume from the Columbia River, a common feature in winter and spring in nearshore waters of the U.S. Pacific Northwest. (c) 2013 Elsevier B.V. All rights reserved.Keywords: Coastal currents, Heceta Bank, Domoic acid, HAB, Pseudo-nitzschia, Juan de Fuca edd
Neutralizing Antibody Fails to Impact the Course of Ebola Virus Infection in Monkeys
Prophylaxis with high doses of neutralizing antibody typically offers protection against challenge with viruses producing acute infections. In this study, we have investigated the ability of the neutralizing human monoclonal antibody, KZ52, to protect against Ebola virus in rhesus macaques. This antibody was previously shown to fully protect guinea pigs from infection. Four rhesus macaques were given 50 mg/kg of neutralizing human monoclonal antibody KZ52 intravenously 1 d before challenge with 1,000 plaque-forming units of Ebola virus, followed by a second dose of 50 mg/kg antibody 4 d after challenge. A control animal was exposed to virus in the absence of antibody treatment. Passive transfer of the neutralizing human monoclonal antibody not only failed to protect macaques against challenge with Ebola virus but also had a minimal effect on the explosive viral replication following infection. We show that the inability of antibody to impact infection was not due to neutralization escape. It appears that Ebola virus has a mechanism of infection propagation in vivo in macaques that is uniquely insensitive even to high concentrations of neutralizing antibody
Pretreatment HLADQA1-HLADRB1 Testing for the Prevention of Azathioprine-Induced Pancreatitis in Inflammatory Bowel Disease: A Prospective Cohort Study
INTRODUCTION:Azathioprine-induced pancreatitis is an idiosyncratic and unpredictable response, occurring in up to 7% of azathioprine-exposed patients with inflammatory bowel disease (IBD). The haplotype HLADQA1-HLADRB1*07:01A\u3eC is strongly associated with azathioprine-induced pancreatitis in IBD. We aimed to evaluate whether pretreatment HLADQA1-HLADRB1*07:01A\u3eC screening will reduce the risk of azathioprine-induced pancreatitis.METHODS:Participants with IBD were screened for HLADQA1-HLADRB1*07:01A\u3eC, and participants with a variant genotype were excluded from azathioprine treatment. Wild-type participants were started on azathioprine and followed for 3 months. The incidence of pancreatitis was compared with unscreened historical controls.RESULTS:HLADQA1-HLADRB1*07:01A\u3eC screening resulted in an 11-fold reduction in the incidence of azathioprine-induced pancreatitis (n = 1/328 or 0.30% vs n = 13/373 or 3.4%). In propensity score-matched cohorts (age and sex), HLA DQA1-HLADRB1*07:01A\u3eC screening was significantly associated with a reduction in the incidence of AZA-induced pancreatitis independent of weight, glucocorticoid exposure, and smoking status (adjusted odds ratio = 0.075, 95% confidence interval = 0.01-0.58, P = 0.01). Up to 45% (n = 271/599) of participants were excluded from azathioprine therapy based on the haplotype in the HLADQA1-HLADRB1*07:01A\u3eC-screened cohort.DISCUSSION:HLADQA1-HLADRB1*07:01A\u3eC screening reduced the risk of azathioprine-induced pancreatitis; however, using this strategy to guide the use of azathioprine therapy in IBD may eliminate a large proportion of patients from being eligible for treatment with azathioprine. In regions where there is access to other IBD therapies, and given the short-term and long-term toxicities associated with azathioprine, HLADQA1-HLADRB1*07:01A\u3eC-screening may be a clinically relevant strategy for enhancing the safe use of azathioprine in IBD. In addition, cost-effectiveness analyses are needed to further solidify the utility of HLADQA1-HLADRB1*07:01A\u3eC screening in IBD populations
The Morningside Initiative: Collaborative Development of a Knowledge Repository to Accelerate Adoption of Clinical Decision Support
The Morningside Initiative is a public-private activity that has evolved from an August, 2007, meeting at the Morningside Inn, in Frederick, MD, sponsored by the Telemedicine and Advanced Technology Research Center (TATRC) of the US Army Medical Research Materiel Command. Participants were subject matter experts in clinical decision support (CDS) and included representatives from the Department of Defense, Veterans Health Administration, Kaiser Permanente, Partners Healthcare System, Henry Ford Health System, Arizona State University, and the American Medical Informatics Association (AMIA). The Morningside Initiative was convened in response to the AMIA Roadmap for National Action on Clinical Decision Support and on the basis of other considerations and experiences of the participants. Its formation was the unanimous recommendation of participants at the 2007 meeting which called for creating a shared repository of executable knowledge for diverse health care organizations and practices, as well as health care system vendors. The rationale is based on the recognition that sharing of clinical knowledge needed for CDS across organizations is currently virtually non-existent, and that, given the considerable investment needed for creating, maintaining and updating authoritative knowledge, which only larger organizations have been able to undertake, this is an impediment to widespread adoption and use of CDS. The Morningside Initiative intends to develop and refine (1) an organizational framework, (2) a technical approach, and (3) CDS content acquisition and management processes for sharing CDS knowledge content, tools, and experience that will scale with growing numbers of participants and can be expanded in scope of content and capabilities. Intermountain Healthcare joined the initial set of participants shortly after its formation. The efforts of the Morningside Initiative are intended to serve as the basis for a series of next steps in a national agenda for CDS. It is based on the belief that sharing of knowledge can be highly effective as is the case in other competitive domains such as genomics. Participants in the Morningside Initiative believe that a coordinated effort between the private and public sectors is needed to accomplish this goal and that a small number of highly visible and respected health care organizations in the public and private sector can lead by example. Ultimately, a future collaborative knowledge sharing organization must have a sustainable long-term business model for financial support
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