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Cost-effectiveness of helicopter versus ground emergency medical services for trauma scene transport in the United States

Sun, 10/25/2015 - 7:55pm

STUDY OBJECTIVE: We determine the minimum mortality reduction that helicopter emergency medical services (EMS) should provide relative to ground EMS for the scene transport of trauma victims to offset higher costs, inherent transport risks, and inevitable overtriage of patients with minor injury.

METHODS: We developed a decision-analytic model to compare the costs and outcomes of helicopter versus ground EMS transport to a trauma center from a societal perspective during a patient's lifetime. We determined the mortality reduction needed to make helicopter transport cost less than $100,000 and $50,000 per quality-adjusted life-year gained compared with ground EMS. Model inputs were derived from the National Study on the Costs and Outcomes of Trauma, National Trauma Data Bank, Medicare reimbursements, and literature. We assessed robustness with probabilistic sensitivity analyses.

RESULTS: Helicopter EMS must provide a minimum of a 15% relative risk reduction in mortality (1.3 lives saved/100 patients with the mean characteristics of the National Study on the Costs and Outcomes of Trauma cohort) to cost less than $100,000 per quality-adjusted life-year gained and a reduction of at least 30% (3.3 lives saved/100 patients) to cost less than $50,000 per quality-adjusted life-year. Helicopter EMS becomes more cost-effective with significant reductions in patients with minor injury who are triaged to air transport or if long-term disability outcomes are improved.

CONCLUSION: Helicopter EMS needs to provide at least a 15% mortality reduction or a measurable improvement in long-term disability to compare favorably with other interventions considered cost-effective. Given current evidence, it is not clear that helicopter EMS achieves this mortality or disability reduction. Reducing overtriage of patients with minor injury to helicopter EMS would improve its cost-effectiveness. Inc. All rights reserved.

Identification of strain-specific B-cell epitopes in Trypanosoma cruzi using genome-scale epitope prediction and high-throughput immunoscreening with peptide arrays

Sun, 10/25/2015 - 7:55pm

BACKGROUND: The factors influencing variation in the clinical forms of Chagas disease have not been elucidated; however, it is likely that the genetics of both the host and the parasite are involved. Several studies have attempted to correlate the T. cruzi strains involved in infection with the clinical forms of the disease by using hemoculture and/or PCR-based genotyping of parasites from infected human tissues. However, both techniques have limitations that hamper the analysis of large numbers of samples. The goal of this work was to identify conserved and polymorphic linear B-cell epitopes of T. cruzi that could be used for serodiagnosis and serotyping of Chagas disease using ELISA.

METHODOLOGY: By performing B-cell epitope prediction on proteins derived from pair of alleles of the hybrid CL Brener genome, we have identified conserved and polymorphic epitopes in the two CL Brener haplotypes. The rationale underlying this strategy is that, because CL Brener is a recent hybrid between the TcII and TcIII DTUs (discrete typing units), it is likely that polymorphic epitopes in pairs of alleles could also be polymorphic in the parental genotypes. We excluded sequences that are also present in the Leishmania major, L. infantum, L. braziliensis and T. brucei genomes to minimize the chance of cross-reactivity. A peptide array containing 150 peptides was covalently linked to a cellulose membrane, and the reactivity of the peptides was tested using sera from C57BL/6 mice chronically infected with the Colombiana (TcI) and CL Brener (TcVI) clones and Y (TcII) strain.

FINDINGS AND CONCLUSIONS: A total of 36 peptides were considered reactive, and the cross-reactivity among the strains is in agreement with the evolutionary origin of the different T. cruzi DTUs. Four peptides were tested against a panel of chagasic patients using ELISA. A conserved peptide showed 95.8% sensitivity, 88.5% specificity, and 92.7% accuracy for the identification of T. cruzi in patients infected with different strains of the parasite. Therefore, this peptide, in association with other T. cruzi antigens, may improve Chagas disease serodiagnosis. Together, three polymorphic epitopes were able to discriminate between the three parasite strains used in this study and are thus potential targets for Chagas disease serotyping.

Oncofetal protein IMP3: a new diagnostic biomarker for laryngeal carcinoma

Sun, 10/25/2015 - 7:55pm

An accurate diagnosis of laryngeal squamous cell carcinoma (LSCC) is essential for patient management. The diagnosis of LSCC, especially in superficial biopsies, can present a diagnostic challenge for pathologists. The ability to diagnose LSCC would be greatly improved by the detection of a tumor-associated antigen. IMP3 is an oncofetal protein associated with aggressive and advanced tumors and is specifically expressed in malignant tumors but not found in benign tissues. The aim of this study was to determine the expression and diagnostic value of IMP3 in LSCC to determine whether it can serve as a diagnostic biomarker. A total of 238 cases (laryngectomy, n = 121; biopsy, n = 117) consisting of 11 laryngeal carcinoma in situ/severe dysplasia and 227 invasive LSCC were examined by immunohistochemistry for IMP3 expression. IMP3 showed strong cytoplasmic staining in 217 (92%) of 238 LSCCs regardless of histologic grade. In addition, 58 (89%) of 65 small biopsies ( < /=5 mm in greatest dimension) containing a minute amount of carcinoma were positive for IMP3. In contrast to malignant tumors, IMP3 expression was not found in any of the adjacent benign squamous epithelium (0/118 cases; 0%), mild or moderate dysplasia (0/139 cases; 0%), or pseudoepitheliomatous hyperplasia (0/99 cases; 0%). In summary, we are the first to describe that IMP3 is a highly sensitive and specific biomarker for LSCC. The expression of IMP3 in LSCC can be used as a positive biomarker to increase the level of confidence in establishing a definitive diagnosis of a malignancy in laryngeal biopsy.

Evaluation of an institution-wide guideline for hyperglycemic emergencies at a tertiary academic medical center

Sun, 10/25/2015 - 7:55pm

BACKGROUND: No previous studies exist examining implementation of an institution-wide guideline and order set for hyperglycemic emergencies (diabetic ketoacidosis [DKA] and hyperosmolar hyperglycemic state [HHS]).

OBJECTIVE: Evaluate the impact of an institutional guideline and order set for hyperglycemic emergencies.

METHODS: This retrospective descriptive study evaluated patients with a diagnosis of DKA or HHS. Two time periods were evaluated: phase 1 (PRE) assessed practice preguideline implementation, and phase 2 (POST) assessed practice postguideline and order set introduction.

RESULTS: A total of 172 patients (91 PRE and 81 POST) were included in the analysis. There was no difference in the mean hospital length of stay (LOS) in the PRE versus POST groups (5.2 +/- 4 vs 5.9 +/- 8.6 days, P = .49). The mean intensive care unit (ICU) LOS was shorter in the POST group (64.8 +/- 19 vs 37.1 +/- 74.8 hours, P < .01). The POST group had an increase in frequency of assessments for clearance of urinary ketones (18 vs 33.3%, P = .03) and beta-hydroxybutyrate (16 vs 37%, P < .01). Frequency of point-of-care glucose testing (12.5 +/- 4.6 vs 15.1 +/- 4.7, P < .01) and time to anion gap closure (13 +/- 9 vs 9.3 +/- 7.4 hours, P < .01) improved in the POST group. There was no difference in the number of patients experiencing hypoglycemia or hypokalemia between both groups.

CONCLUSIONS: Implementation of an institutional guideline and order set for hyperglycemic emergencies decreased ICU LOS and time to anion gap closure, with no difference in rates of hypoglycemia.

Systolic left ventricular function according to left ventricular concentricity and dilatation in hypertensive patients: the Losartan Intervention For Endpoint reduction in hypertension study

Sun, 10/25/2015 - 7:55pm

BACKGROUND: Left ventricular hypertrophy [LVH, high left ventricular mass (LVM)] is traditionally classified as concentric or eccentric based on left ventricular relative wall thickness. We evaluated left ventricular systolic function in a new four-group LVH classification based on left ventricular dilatation [high left ventricular end-diastolic volume (EDV) index and concentricity (LVM/EDV)] in hypertensive patients.

METHODS AND RESULTS: Nine hundred thirty-nine participants in the Losartan Intervention For Endpoint reduction in hypertension (LIFE) echocardiography substudy had measurable LVM at enrolment. Patients with LVH (LVM/body surface area > /=116 g/m in men and > /=96 g/m in women) were divided into four groups; 'eccentric nondilated' (normal LVM/EDV and EDV), 'eccentric dilated' (increased EDV, normal LVM/EDV), 'concentric nondilated' (increased LVM/EDV with normal EDV), and 'concentric dilated' (increased LVM/EDV and EDV) and compared to patients with normal LVM. At baseline, 12% had eccentric nondilated, 20% eccentric dilated, 29% concentric nondilated, and 14% concentric dilated LVH, with normal LVM in 25%. Compared with the concentric nondilated LVH group, those with concentric dilated LVH had significantly lower pulse pressure/stroke index and ejection fraction; higher LVM index, stroke volume, cardiac output, left ventricular midwall shortening, left atrial volume and isovolumic relaxation time; and more had segmental wall motion abnormalities (all P < 0.05). Similar differences existed between patients with eccentric dilated and those with eccentric nondilated LVH (all P < 0.05). Compared with patients with normal LVM, the eccentric nondilated had higher LV stroke volume, pulse pressure/stroke index, Cornell voltage product and SBP, and lower heart rate and fewer were African-American (all P < 0.05).

CONCLUSION: The new four-group classification of LVH identifies dilated subgroups with reduced left ventricular function among patients currently classified with eccentric or concentric LVH.

Regional implementation of a pediatric cardiology chest pain guideline using SCAMPs methodology

Sun, 10/25/2015 - 7:55pm

BACKGROUND AND OBJECTIVES: Chest pain is a complaint for which children are frequently evaluated. Cardiac causes are rarely found despite expenditure of considerable time and resources. We describe validation throughout New England of a clinical guideline for cost-effective evaluation of pediatric patients first seen by a cardiologist for chest pain using a unique methodology termed the Standardized Clinical Assessment and Management Plans (SCAMPs).

METHODS: A total of 1016 ambulatory patients, ages 7 to 21 years initially seen for chest pain at Boston Children's Hospital (BCH) or the New England Congenital Cardiology Association (NECCA) practices, were evaluated by using a SCAMPs chest pain guideline. Findings were analyzed for diagnostic elements, patterns of care, and compliance with the guideline. Results from the NECCA practices were compared with those of Boston Children's Hospital, a regional core academic center.

RESULTS: Two patients had chest pain due to a cardiac etiology, 1 with pericarditis and 1 with an anomalous coronary artery origin. Testing performed outside of guideline recommendations demonstrated only incidental findings. Patients returning for persistent symptoms did not have cardiac disease. The pattern of care for the NECCA practices and BCH differed minimally.

CONCLUSIONS: By using SCAMPs methodology, we have demonstrated that chest pain in children is rarely caused by heart disease and can be evaluated in the ambulatory setting efficiently and effectively using minimal resources. The methodology can be implemented regionally across a wide range of clinical practice settings and its approach can overcome a number of barriers that often limit clinical practice guideline implementation.

Cross reactivity of serum antibody responses elicited by DNA vaccines expressing HA antigens from H1N1 subtype influenza vaccines in the past 30 years

Sun, 10/25/2015 - 7:55pm

In the past three decades, ten H1 subtype influenza vaccines have been recommended for global seasonal flu vaccination. Some of them were used only for one year before being replaced by another H1 flu vaccine while others may be used for up to seven years. While the selection of a new seasonal flu vaccine was based on the escape of a new emerging virus that was not effectively protected by the existing flu formulation, there is limited information on the magnitude and breadth of cross reactivity among H1 subtype virus circulation over a long period. In the current study, HA-expressing DNA vaccines were constructed to express individual HA antigens from H1 subtype vaccines used in the past 30 y. Rabbits naive to HA antibody responses were immunized with these HA DNA vaccines and the cross reactivity of these sera against HA antigen and related H1 viruses in the same period was studied. Our data indicate that the level of cross reactivity was different for different viral isolates and the key mutations responsible for the cross reactivity may involve only a limited number of residues. Our results provide useful information for the development of improved seasonal vaccines than can achieve broad protection against viruses within the same H1 subtype.

Cyclic-di-GMP and cyclic-di-AMP activate the NLRP3 inflammasome

Sun, 10/25/2015 - 7:55pm

The cyclic dinucleotides 3'-5'diadenylate (c-diAMP) and 3'-5' diguanylate (c-diGMP) are important bacterial second messengers that have recently been shown to stimulate the secretion of type I Interferons (IFN-Is) through the c-diGMP-binding protein MPYS/STING. Here, we show that physiologically relevant levels of cyclic dinucleotides also stimulate a robust secretion of IL-1beta through the NLRP3 inflammasome. Intriguingly, this response is independent of MPYS/STING. Consistent with most NLRP3 inflammasome activators, the response to c-diGMP is dependent on the mobilization of potassium and calcium ions. However, in contrast to other NLRP3 inflammasome activators, this response is not associated with significant changes in mitochondrial potential or the generation of mitochondrial reactive oxygen species. Thus, cyclic dinucleotides activate the NLRP3 inflammasome through a unique pathway that could have evolved to detect pervasive bacterial pathogen-associated molecular patterns associated with intracellular infections.

Medical Library Marketing: An Investigation of Current Definitions and Practices - Preliminary Report of Survey Results

Thu, 10/22/2015 - 12:08pm

Marketing is essential for medical and health science libraries. However, there has been no profession wide analysis of marketing definitions and incorporation for this specific field. A study was undertaken to investigate the current state of marketing understanding and practice in medical and health science libraries. Specifically, this study looks at individual, institutional, and profession wide marketing definitions, practices, trends, and gaps – creating a solid foundation and framework for future work.

This poster reports the preliminary results from a survey looking at current medical/health science library wide opinions and practices concerning medical/health science library marketing. The survey was distributed through various listserves and targeted emails to professional medical/health science librarians. Questions focused on an individual’s perceptions and definitions of marketing for themselves, within their institutions, and for medical librarianship as a whole. Results, explanations, and implications are detailed, as well as plans for further study and resource development based on findings.

A survey of big data research

Wed, 10/21/2015 - 10:15am

Big data create values for business and research, but pose significant challenges in terms of networking, storage, management, analytics, and ethics. Multidisciplinary collaborations from engineers, computer scientists, statisticians, and social scientists are needed to tackle, discover, and understand big data. This survey presents an overview of big data initiatives, technologies, and research in industries and academia, and discusses challenges and potential solutions.

Targeting and Customizing Research Data Management Services (RDM)

Tue, 10/20/2015 - 1:29pm

Designing library services is not new to our field. Service design done right is both challenging and rewarding. In this issue of the Journal of eScience Librarianship, librarians across the country write about the importance of providing a solid Research Data Management (RDM) Service, coupled with targeting institutional partners and solid education practices.

Not just full of hot air: hyperbaric oxygen therapy increases survival in cases of necrotizing soft tissue infections.

Mon, 10/19/2015 - 10:44am

BACKGROUND: The utility of hyperbaric oxygen therapy (HBOT) in the treatment of necrotizing soft tissue infections (NSTIs) has not been proved. Previous studies have been subject to substantial selection bias because HBOT is not available universally at all medical centers, and there is often considerable delay associated with its initiation. We examined the utility of HBOT for the treatment of NSTI in the modern era by isolating centers that have their own HBOT facilities.

METHODS: We queried all centers in the University Health Consortium (UHC) database from 2008 to 2010 that have their own HBOT facilities (n=14). Cases of NSTI were identified by International Classification of Diseases, Ninth Revision (ICD-9) diagnosis codes, which included Fournier gangrene (608.83), necrotizing fasciitis (728.86), and gas gangrene (040.0). Status of HBOT was identified by the presence (HBOT) or absence (control) of ICD-9 procedure code 93.95. Our cohort was risk-stratified and matched by UHC's validated severity of illness (SOI) score. Comparisons were then made using univariate tests of association and multivariable logistic regression.

RESULTS: There were 1,583 NSTI cases at the 14 HBOT-capable centers. 117 (7%) cases were treated with HBOT. Univariate analysis showed that there was no difference between HBOT and control groups in hospital length of stay, direct cost, complications, and mortality across the three less severe SOI classes (minor, moderate, and major). However, for extreme SOI the HBOT group had fewer complications (45% vs. 66%; p

CONCLUSION: At HBOT-capable centers, receiving HBOT was associated with a significant survival benefit. Use of HBOT in conjunction with current practices for the treatment of NSTI can be both a cost-effective and life-saving therapy, in particular for the sickest patients.

Plasma microRNAs are associated with atrial fibrillation and change after catheter ablation (the miRhythm study)

Mon, 10/19/2015 - 10:19am

BACKGROUND: MicroRNAs (miRNAs) are associated with cardiovascular disease and control gene expression and are detectable in the circulation.

OBJECTIVE: The purpose of this study was to test the hypothesis that circulating miRNAs may be associated with atrial fibrillation (AF).

METHODS: Using a prospective study design powered to detect subtle differences in miRNAs, we quantified plasma expression of 86 miRNAs by high-throughput quantitative reverse transcriptase-polymerase chain reaction in 112 participants with AF and 99 without AF. To examine parallels between cardiac and plasma miRNA profiles, we quantified atrial tissue and plasma miRNA expression using quantitative reverse transcriptase-polymerase chain reaction in 31 participants undergoing surgery. We also explored the hypothesis that lower AF burden after ablation would be reflected in the circulating blood pool by examining change in plasma miRNAs after AF ablation (n = 47).

RESULTS: Mean age of the cohort was 59 years; 58% of participants were men. Plasma miRs-21 and 150 were 2-fold lower in participants with AF than in those without AF after adjustment (P ≤.0006). Plasma levels of miRs-21 and 150 also were lower in participants with paroxysmal AF than in those with persistent AF (P

CONCLUSION: Cardiac miRs-21 and 150 are known to regulate genes implicated in atrial remodeling. Our findings show associations between plasma miRs-21 and 150 and AF, suggesting that circulating miRNAs can provide insights into cardiac gene regulation.

Open Access: Considerations for Accessing and Using Scholarly Literature

Fri, 10/16/2015 - 10:01am

Blog post to AEA365, a blog sponsored by the American Evaluation Association (AEA) dedicated to highlighting Hot Tips, Cool Tricks, Rad Resources, and Lessons Learned for evaluators. The American Evaluation Association is an international professional association of evaluators devoted to the application and exploration of program evaluation, personnel evaluation, technology, and many other forms of evaluation. Evaluation involves assessing the strengths and weaknesses of programs, policies, personnel, products, and organizations to improve their effectiveness.