Estimating Sensitivity of Laboratory Testing for Influenza in Canada through Modelling

Background: The weekly proportion of laboratory tests that are positive for influenza is used in public health surveillance systems to identify periods of influenza activity. We aimed to estimate the sensitivity of influenza testing in Canada based on results of a national respiratory virus surveillance system. Methods and Findings: The weekly number of influenza-negative tests from 1999 to 2006 was modelled as a function of laboratory-confirmed positive tests for influenza, respiratory syncytial virus (RSV), adenovirus and parainfluenza viruses, seasonality, and trend using Poisson regression. Sensitivity was calculated as the number of influenza positive tests divided by the number of influenza positive tests plus the model-estimated number of false negative tests. The sensitivity of influenza testing was estimated to be 33 % (95%CI 32–34%), varying from 30–40 % depending on the season and region. Conclusions: The estimated sensitivity of influenza tests reported to this national laboratory surveillance system is considerably less than reported test characteristics for most laboratory tests. A number of factors may explain this difference, including sample quality and specimen procurement issues as well as test characteristics. Improved diagnosis would permit better estimation of the burden of influenza

Systematic review of interventions to encourage careers in academic medicine

Aims: Academic medicine is a career route that historically struggles to recruit and retain suitable doctors. The aim of this paper is to review the evidence for interventions to encourage careers in academic medicine by way of a descriptive systematic review. Methods: Key databases were searched in February 2017. Studies that evaluated interventions to encourage careers in academic medicine and that used a pre–post analysis or included a comparison group were included. Interventions reporting only learner satisfaction were excluded. The review was specific to medical students and graduates. Results: Twenty-four studies were identified for inclusion within the review. The included studies identified interventions across five domains: postgraduate funding, postgraduate training, mentoring, undergraduate interventions, and institutional change. The papers varied in terms of strength of conclusion and method of analysis with broad, structured, well-funded programs having the most palpable results. Conclusions: The five domains identified offer a framework that can be used by institutions who wish to develop similar programs. It also offers a body of research on which an evidence base can be built

Restriction of meat, fish, and poultry in omnivores improves mood: A pilot randomized controlled trial

<p>Abstract</p> <p>Background</p> <p>Omnivorous diets are high in arachidonic acid (AA) compared to vegetarian diets. Research shows that high intakes of AA promote changes in brain that can disturb mood. Omnivores who eat fish regularly increase their intakes of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), fats that oppose the negative effects of AA in vivo. In a recent cross-sectional study, omnivores reported significantly worse mood than vegetarians despite higher intakes of EPA and DHA. This study investigated the impact of restricting meat, fish, and poultry on mood.</p> <p>Findings</p> <p>Thirty-nine omnivores were randomly assigned to a control group consuming meat, fish, and poultry daily (OMN); a group consuming fish 3-4 times weekly but avoiding meat and poultry (FISH), or a vegetarian group avoiding meat, fish, and poultry (VEG). At baseline and after two weeks, participants completed a food frequency questionnaire, the Profile of Mood States questionnaire and the Depression Anxiety and Stress Scales. After the diet intervention, VEG participants reduced their EPA, DHA, and AA intakes, while FISH participants increased their EPA and DHA intakes. Mood scores were unchanged for OMN or FISH participants, but several mood scores for VEG participants improved significantly after two weeks.</p> <p>Conclusions</p> <p>Restricting meat, fish, and poultry improved some domains of short-term mood state in modern omnivores. To our knowledge, this is the first trial to examine the impact of restricting meat, fish, and poultry on mood state in omnivores.</p

Geckos decouple fore- and hind limb kinematics in response to changes in incline

This work is supported by an NSF grant (NSF IOS-1147043) to TE

Systematic review of mass media interventions designed to improve public recognition of stroke symptoms, emergency response and early treatment

<p>Abstract</p> <p>Background</p> <p>Mass media interventions have been implemented to improve emergency response to stroke given the emergence of effective acute treatments, but their impact is unclear.</p> <p>Methods</p> <p>Systematic review of mass media interventions aimed at improving emergency response to stroke, with narrative synthesis and review of intervention development.</p> <p>Results</p> <p>Ten studies were included (six targeted the public, four both public and professionals) published between 1992 and 2010. Only three were controlled before and after studies, and only one had reported how the intervention was developed. Campaigns aimed only at the public reported significant increase in awareness of symptoms/signs, but little impact on awareness of need for emergency response. Of the two controlled before and after studies, one reported no impact on those over 65 years, the age group at increased risk of stroke and most likely to witness a stroke, and the other found a significant increase in awareness of two or more warning signs of stroke in the same group post-intervention. One campaign targeted at public and professionals did not reduce time to presentation at hospital to within two hours, but increased and sustained thrombolysis rates. This suggests the campaign had a primary impact on professionals and improved the way that services for stroke were organised.</p> <p>Conclusions</p> <p>Campaigns aimed at the public may raise awareness of symptoms/signs of stroke, but have limited impact on behaviour. Campaigns aimed at both public and professionals may have more impact on professionals than the public. New campaigns should follow the principles of good design and be robustly evaluated.</p

A novel miniature in-line load-cell to measure in-situ tensile forces in the tibialis anterior tendon of rats.

Direct measurements of muscular forces usually require a substantial rearrangement of the biomechanical system. To circumvent this problem, various indirect techniques have been used in the past. We introduce a novel direct method, using a lightweight (~0.5 g) miniature (3 x 3 x 7 mm) in-line load-cell to measure tension in the tibialis anterior tendon of rats. A linear motor was used to produce force-profiles to assess linearity, step-response, hysteresis and frequency behavior under controlled conditions. Sensor responses to a series of rectangular force-pulses correlated linearly (R2 = 0.999) within the range of 0-20 N. The maximal relative error at full scale (20 N) was 0.07% of the average measured signal. The standard deviation of the mean response to repeated 20 N force pulses was ± 0.04% of the mean response. The step-response of the load-cell showed the behavior of a PD2T2-element in control-engineering terminology. The maximal hysteretic error was 5.4% of the full-scale signal. Sinusoidal signals were attenuated maximally (-4 dB) at 200 Hz, within a measured range of 0.01-200 Hz. When measuring muscular forces this should be of minor concern as the fusion-frequency of muscles is generally much lower. The newly developed load-cell measured tensile forces of up to 20 N, without inelastic deformation of the sensor. It qualifies for various applications in which it is of interest directly to measure forces within a particular tendon causing only minimal disturbance to the biomechanical system

A copula model for marked point processes

The final publication (Diao, Liqun, Richard J. Cook, and Ker-Ai Lee. (2013) A copula model for marked point processes. Lifetime Data Analysis, 19(4): 463-489) is available at Springer via http://dx.doi.org/10.1007/s10985-013-9259-3Many chronic diseases feature recurring clinically important events. In addition, however, there often exists a random variable which is realized upon the occurrence of each event reflecting the severity of the event, a cost associated with it, or possibly a short term response indicating the effect of a therapeutic intervention. We describe a novel model for a marked point process which incorporates a dependence between continuous marks and the event process through the use of a copula function. The copula formulation ensures that event times can be modeled by any intensity function for point processes, and any multivariate model can be specified for the continuous marks. The relative efficiency of joint versus separate analyses of the event times and the marks is examined through simulation under random censoring. An application to data from a recent trial in transfusion medicine is given for illustration.Natural Sciences and Engineering Research Council of Canada (RGPIN 155849); Canadian Institutes for Health Research (FRN 13887); Canada Research Chair (Tier 1) – CIHR funded (950-226626

Relationship between human tumour angiogenic profile and combretastatin-induced vascular shutdown: an exploratory study

Combretastatin-A4-phosphate (CA4P) acts most effectively against immature tumour vasculature. We investigated whether histological angiogenic profile can explain the differential sensitivity of human tumours to CA4P, by correlating the kinetic changes demonstrated by dynamic MRI (DCE-MRI) in response to CA4P, with tumour immunohistochemical angiogenic markers. Tissue was received from 24 patients (mean age 59, range 32–73, 18 women, 6 men). An angiogenic profile was performed using standard immunohistochemical techniques. Dynamic MRI data were obtained for the same patients before and 4 h after CA4P. Three patients showed a statistically significant fall in Ktrans following CA4P, and one a statistically significant fall in IAUGC60. No statistically significant correlations were seen between the continuous or categorical variables and the DCE-MRI kinetic parameters other than between ang-2 and Ktrans (P=0.044). In conclusion, we found no strong relationships between changes in DCE-MRI kinetic variables following CA4P and the immunohistochemical angiogenic profile