41 research outputs found

    The Biosurveillance Analytics Resource Directory (BARD): Facilitating the Use of Epidemiological Models for Infectious Disease Surveillance

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    Epidemiological modeling for infectious disease is important for disease management and its routine implementation needs to be facilitated through better description of models in an operational context. A standardized model characterization process that allows selection or making manual comparisons of available models and their results is currently lacking. A key need is a universal framework to facilitate model description and understanding of its features. Los Alamos National Laboratory (LANL) has developed a comprehensive framework that can be used to characterize an infectious disease model in an operational context. The framework was developed through a consensus among a panel of subject matter experts. In this paper, we describe the framework, its application to model characterization, and the development of the Biosurveillance Analytics Resource Directory (BARD; http://brd.bsvgateway.org/brd/), to facilitate the rapid selection of operational models for specific infectious/communicable diseases. We offer this framework and associated database to stakeholders of the infectious disease modeling field as a tool for standardizing model description and facilitating the use of epidemiological models

    Do citations and readership identify seminal publications?

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    This work presents a new approach for analysing the ability of existing research metrics to identify research which has strongly influenced future developments. More specifically, we focus on the ability of citation counts and Mendeley reader counts to distinguish between publications regarded as seminal and publications regarded as literature reviews by field experts. The main motivation behind our research is to gain a better understanding of whether and how well the existing research metrics relate to research quality. For this experiment we have created a new dataset which we call TrueImpactDataset and which contains two types of publications, seminal papers and literature reviews. Using the dataset, we conduct a set of experiments to study how citation and reader counts perform in distinguishing these publication types, following the intuition that causing a change in a field signifies research quality. Our research shows that citation counts work better than a random baseline (by a margin of 10%) in distinguishing important seminal research papers from literature reviews while Mendeley reader counts do not work better than the baseline

    Assessing the Quality of Clinical Teachers: A Systematic Review of Content and Quality of Questionnaires for Assessing Clinical Teachers

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    BACKGROUND: Learning in a clinical environment differs from formal educational settings and provides specific challenges for clinicians who are teachers. Instruments that reflect these challenges are needed to identify the strengths and weaknesses of clinical teachers. OBJECTIVE: To systematically review the content, validity, and aims of questionnaires used to assess clinical teachers. DATA SOURCES: MEDLINE, EMBASE, PsycINFO and ERIC from 1976 up to March 2010. REVIEW METHODS: The searches revealed 54 papers on 32 instruments. Data from these papers were documented by independent researchers, using a structured format that included content of the instrument, validation methods, aims of the instrument, and its setting. Results : Aspects covered by the instruments predominantly concerned the use of teaching strategies (included in 30 instruments), supporter role (29), role modeling (27), and feedback (26). Providing opportunities for clinical learning activities was included in 13 instruments. Most studies referred to literature on good clinical teaching, although they failed to provide a clear description of what constitutes a good clinical teacher. Instrument length varied from 1 to 58 items. Except for two instruments, all had to be completed by clerks/residents. Instruments served to provide formative feedback ( instruments) but were also used for resource allocation, promotion, and annual performance review (14 instruments). All but two studies reported on internal consistency and/or reliability; other aspects of validity were examined less frequently. CONCLUSIONS: No instrument covered all relevant aspects of clinical teaching comprehensively. Validation of the instruments was often limited to assessment of internal consistency and reliability. Available instruments for assessing clinical teachers should be used carefully, especially for consequential decisions. There is a need for more valid comprehensive instruments

    Zika Virus: What Have We Learnt Since the Start of the Recent Epidemic?

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    Zika is a viral disease transmitted mainly by mosquitoes of the genus Aedes. In recent years, it has expanded geographically, changing from an endemic mosquito-borne disease across equatorial Asia and Africa, to an epidemic disease causing large outbreaks in several areas of the world. With the recent Zika virus (ZIKV) outbreaks in the Americas, the disease has become a focus of attention of public health agencies and of the international research community, especially due to an association with neurological disorders in adults and to the severe neurological and ophthalmological abnormalities found in fetuses and newborns of mothers exposed to ZIKV during pregnancy. A large number of studies have been published in the last 3 years, revealing the structure of the virus, how it is transmitted and how it affects human cells. Many different animal models have been developed, which recapitulate several features of ZIKV disease and its neurological consequences. Moreover, several vaccine candidates are now in active preclinical development, and three of them have already entered phase I clinical trials. Likewise, many different compounds targeting viral and cellular components are being tested in in vitro and in experimental animal models. This review aims to discuss the current state of this rapidly growing literature from a multidisciplinary perspective, as well as to present an overview of the public health response to Zika and of the perspectives for the prevention and treatment of this disease

    Albiglutide and cardiovascular outcomes in patients with type 2 diabetes and cardiovascular disease (Harmony Outcomes): a double-blind, randomised placebo-controlled trial

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    Background: Glucagon-like peptide 1 receptor agonists differ in chemical structure, duration of action, and in their effects on clinical outcomes. The cardiovascular effects of once-weekly albiglutide in type 2 diabetes are unknown. We aimed to determine the safety and efficacy of albiglutide in preventing cardiovascular death, myocardial infarction, or stroke. Methods: We did a double-blind, randomised, placebo-controlled trial in 610 sites across 28 countries. We randomly assigned patients aged 40 years and older with type 2 diabetes and cardiovascular disease (at a 1:1 ratio) to groups that either received a subcutaneous injection of albiglutide (30–50 mg, based on glycaemic response and tolerability) or of a matched volume of placebo once a week, in addition to their standard care. Investigators used an interactive voice or web response system to obtain treatment assignment, and patients and all study investigators were masked to their treatment allocation. We hypothesised that albiglutide would be non-inferior to placebo for the primary outcome of the first occurrence of cardiovascular death, myocardial infarction, or stroke, which was assessed in the intention-to-treat population. If non-inferiority was confirmed by an upper limit of the 95% CI for a hazard ratio of less than 1·30, closed testing for superiority was prespecified. This study is registered with ClinicalTrials.gov, number NCT02465515. Findings: Patients were screened between July 1, 2015, and Nov 24, 2016. 10 793 patients were screened and 9463 participants were enrolled and randomly assigned to groups: 4731 patients were assigned to receive albiglutide and 4732 patients to receive placebo. On Nov 8, 2017, it was determined that 611 primary endpoints and a median follow-up of at least 1·5 years had accrued, and participants returned for a final visit and discontinuation from study treatment; the last patient visit was on March 12, 2018. These 9463 patients, the intention-to-treat population, were evaluated for a median duration of 1·6 years and were assessed for the primary outcome. The primary composite outcome occurred in 338 (7%) of 4731 patients at an incidence rate of 4·6 events per 100 person-years in the albiglutide group and in 428 (9%) of 4732 patients at an incidence rate of 5·9 events per 100 person-years in the placebo group (hazard ratio 0·78, 95% CI 0·68–0·90), which indicated that albiglutide was superior to placebo (p<0·0001 for non-inferiority; p=0·0006 for superiority). The incidence of acute pancreatitis (ten patients in the albiglutide group and seven patients in the placebo group), pancreatic cancer (six patients in the albiglutide group and five patients in the placebo group), medullary thyroid carcinoma (zero patients in both groups), and other serious adverse events did not differ between the two groups. There were three (<1%) deaths in the placebo group that were assessed by investigators, who were masked to study drug assignment, to be treatment-related and two (<1%) deaths in the albiglutide group. Interpretation: In patients with type 2 diabetes and cardiovascular disease, albiglutide was superior to placebo with respect to major adverse cardiovascular events. Evidence-based glucagon-like peptide 1 receptor agonists should therefore be considered as part of a comprehensive strategy to reduce the risk of cardiovascular events in patients with type 2 diabetes. Funding: GlaxoSmithKline

    Global, regional, and national disability-adjusted life-years (DALYs) for 333 diseases and injuries and healthy life expectancy (HALE) for 195 countries and territories, 1990–2016: a systematic analysis for the Global Burden of Disease Study 2016

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    BACKGROUND: Measurement of changes in health across locations is useful to compare and contrast changing epidemiological patterns against health system performance and identify specific needs for resource allocation in research, policy development, and programme decision making. Using the Global Burden of Diseases, Injuries, and Risk Factors Study 2016, we drew from two widely used summary measures to monitor such changes in population health: disability-adjusted life-years (DALYs) and healthy life expectancy (HALE). We used these measures to track trends and benchmark progress compared with expected trends on the basis of the Socio-demographic Index (SDI). METHODS: We used results from the Global Burden of Diseases, Injuries, and Risk Factors Study 2016 for all-cause mortality, cause-specific mortality, and non-fatal disease burden to derive HALE and DALYs by sex for 195 countries and territories from 1990 to 2016. We calculated DALYs by summing years of life lost and years of life lived with disability for each location, age group, sex, and year. We estimated HALE using age-specific death rates and years of life lived with disability per capita. We explored how DALYs and HALE differed from expected trends when compared with the SDI: the geometric mean of income per person, educational attainment in the population older than age 15 years, and total fertility rate. FINDINGS: The highest globally observed HALE at birth for both women and men was in Singapore, at 75·2 years (95% uncertainty interval 71·9-78·6) for females and 72·0 years (68·8-75·1) for males. The lowest for females was in the Central African Republic (45·6 years [42·0-49·5]) and for males was in Lesotho (41·5 years [39·0-44·0]). From 1990 to 2016, global HALE increased by an average of 6·24 years (5·97-6·48) for both sexes combined. Global HALE increased by 6·04 years (5·74-6·27) for males and 6·49 years (6·08-6·77) for females, whereas HALE at age 65 years increased by 1·78 years (1·61-1·93) for males and 1·96 years (1·69-2·13) for females. Total global DALYs remained largely unchanged from 1990 to 2016 (-2·3% [-5·9 to 0·9]), with decreases in communicable, maternal, neonatal, and nutritional (CMNN) disease DALYs offset by increased DALYs due to non-communicable diseases (NCDs). The exemplars, calculated as the five lowest ratios of observed to expected age-standardised DALY rates in 2016, were Nicaragua, Costa Rica, the Maldives, Peru, and Israel. The leading three causes of DALYs globally were ischaemic heart disease, cerebrovascular disease, and lower respiratory infections, comprising 16·1% of all DALYs. Total DALYs and age-standardised DALY rates due to most CMNN causes decreased from 1990 to 2016. Conversely, the total DALY burden rose for most NCDs; however, age-standardised DALY rates due to NCDs declined globally. INTERPRETATION: At a global level, DALYs and HALE continue to show improvements. At the same time, we observe that many populations are facing growing functional health loss. Rising SDI was associated with increases in cumulative years of life lived with disability and decreases in CMNN DALYs offset by increased NCD DALYs. Relative compression of morbidity highlights the importance of continued health interventions, which has changed in most locations in pace with the gross domestic product per person, education, and family planning. The analysis of DALYs and HALE and their relationship to SDI represents a robust framework with which to benchmark location-specific health performance. Country-specific drivers of disease burden, particularly for causes with higher-than-expected DALYs, should inform health policies, health system improvement initiatives, targeted prevention efforts, and development assistance for health, including financial and research investments for all countries, regardless of their level of sociodemographic development. The presence of countries that substantially outperform others suggests the need for increased scrutiny for proven examples of best practices, which can help to extend gains, whereas the presence of underperforming countries suggests the need for devotion of extra attention to health systems that need more robust support. FUNDING: Bill & Melinda Gates Foundation

    Type 1 Fimbriae of Salmonella enterica Serovar Typhimurium Bind to Enterocytes and Contribute to Colonization of Swine In Vivo

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    Salmonella enterica serovar Typhimurium strain 798 is a clinical isolate from a pig and is known to be able to cause persistent, asymptomatic infections. This strain also is known to exist in two phenotypes (adhesive and nonadhesive to enterocytes) and can switch between the two phenotypes at a rate consistent with phase variation. Cells in the adhesive phenotype are more readily phagocytosed by leukocytes than nonadhesive cells. Once in a leukocyte, adhesive-phase cells survive while nonadhesive-phase cells die. In the present study, nonadhesive mutants were obtained with the transposon TnphoA. A nonadhesive mutant was selected for study and was shown by electron microscopy not to produce fimbriae. The gene encoding the adhesin was cloned and sequenced. Based on its sequence, the adhesin was shown to be FimA, the major subunit of type 1 fimbriae. The nonadhesive mutant was attenuated in its ability to colonize both mouse and pig intestines, but remained capable of systemic spread in mice. The nonadhesive mutant was phagocytosed to the same extent as parental cells in the adhesive phase and then survived intracellularly. These results demonstrated that type 1 fimbriae were important for attachment to enterocytes and promoted intestinal colonization. However, they were not important in promoting phagocytosis or intracellular survival

    Internet-based biosurveillance methods for vector-borne diseases: Are they novel public health tools or just novelties?

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    <div><p>Internet-based surveillance methods for vector-borne diseases (VBDs) using “big data” sources such as Google, Twitter, and internet newswire scraping have recently been developed, yet reviews on such “digital disease detection” methods have focused on respiratory pathogens, particularly in high-income regions. Here, we present a narrative review of the literature that has examined the performance of internet-based biosurveillance for diseases caused by vector-borne viruses, parasites, and other pathogens, including Zika, dengue, other arthropod-borne viruses, malaria, leishmaniasis, and Lyme disease across a range of settings, including low- and middle-income countries. The fundamental features, advantages, and drawbacks of each internet big data source are presented for those with varying familiarity of “digital epidemiology.” We conclude with some of the challenges and future directions in using internet-based biosurveillance for the surveillance and control of VBD.</p></div

    Molecular and clinical effects of aromatase inhibitor therapy on skeletal muscle function in early-stage breast cancer

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    We evaluated biochemical changes in skeletal muscle of women with breast cancer initiating aromatase inhibitors (AI), including oxidation of ryanodine receptor RyR1 and loss of stabilizing protein calstabin1, and detailed measures of muscle function. Fifteen postmenopausal women with stage I–III breast cancer planning to initiate AI enrolled. Quadriceps muscle biopsy, dual-energy x-ray absorptiometry, isokinetic dynamometry, Short Physical Performance Battery, grip strength, 6-min walk, patient-reported outcomes, and serologic measures of bone turnover were assessed before and after 6 months of AI. Post-AI exposure, oxidation of RyR1 significantly increased (0.23 ± 0.37 vs. 0.88 ± 0.80, p < 0.001) and RyR1-bound calstabin1 significantly decreased (1.69 ± 1.53 vs. 0.74 ± 0.85, p < 0.001), consistent with dysfunctional calcium channels in skeletal muscle. Grip strength significantly decreased at 6 months. No significant differences were seen in isokinetic dynamometry measures of muscle contractility, fatigue resistance, or muscle recovery post-AI exposure. However, there was significant correlation between oxidation of RyR1 with muscle power (r = 0.60, p = 0.02) and muscle fatigue (r = 0.57, p = 0.03). Estrogen deprivation therapy for breast cancer resulted in maladaptive changes in skeletal muscle, consistent with the biochemical signature of dysfunctional RyR1 calcium channels. Future studies will evaluate longer trajectories of muscle function change and include other high bone turnover states, such as bone metastases
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