Impact of patient global assessment on achieving remission in patients with rheumatoid arthritis: A multinational study using the METEOR database

OBJECTIVE: There is an ongoing debate about excluding patient's global assessment (PtGA) from composite and Boolean-based definitions of rheumatoid arthritis (RA) remission. This study aimed at determining the influence of PtGA on RA disease states, exploring differences across countries, and understanding the association between PtGA, measures of disease impact (symptoms), and markers of disease activity (inflammation). METHODS: Cross-sectional data from the Measurement of Efficacy of Treatment in the Era of Outcome in Rheumatology international database were used. We calculated the proportion of patients failing American College of Rheumatology/European League Against Rheumatism Boolean-based remission (4-variable remission) solely due to PtGA (PtGA-near-remission) in the overall sample and in the most representative countries (i.e., those with >3,000 patients in the database). Multivariable linear regression models were used to identify the main determinants of PtGA, grouped in predominantly inflammatory impact factors (28 tender joint counts, 28 swollen joint counts, and C-reactive protein level) and disease impact factors (pain and function). RESULTS: This study included 27,768 patients. Excluding PtGA from the Boolean-based definition (3-variable remission) increased the remission rate from 5.8% to 15.8%. The rate of PtGA-near-remission varied considerably between countries, from 1.7% in India to 17.9% in Portugal. One-third of the patients in PtGA-near-remission group scored PtGA >4 of 10. Pain and function were the main correlates of PtGA, with inflammation-related variables contributing less to the model (R2 = 0.57). CONCLUSION: PtGA is moderately related to joint inflammation overall, but only weakly so in low levels of disease activity. A considerable proportion of patients otherwise in biologic remission still perceive high PtGA, putting them at risk of excessive immunosuppressive treatment

Testing stock market convergence: a non-linear factor approach

This paper applies the Phillips and Sul (Econometrica 75(6):1771–1855, 2007) method to test for convergence in stock returns to an extensive dataset including monthly stock price indices for five EU countries (Germany, France, the Netherlands, Ireland and the UK) as well as the US between 1973 and 2008. We carry out the analysis on both sectors and individual industries within sectors. As a first step, we use the Stock and Watson (J Am Stat Assoc 93(441):349–358, 1998) procedure to filter the data in order to extract the long-run component of the series; then, following Phillips and Sul (Econometrica 75(6):1771–1855, 2007), we estimate the relative transition parameters. In the case of sectoral indices we find convergence in the middle of the sample period, followed by divergence, and detect four (two large and two small) clusters. The analysis at a disaggregate, industry level again points to convergence in the middle of the sample, and subsequent divergence, but a much larger number of clusters is now found. Splitting the cross-section into two subgroups including euro area countries, the UK and the US respectively, provides evidence of a global convergence/divergence process not obviously influenced by EU policies

A paradox of syntactic priming: why response tendencies show priming for passives, and response latencies show priming for actives

Speakers tend to repeat syntactic structures across sentences, a phenomenon called syntactic priming. Although it has been suggested that repeating syntactic structures should result in speeded responses, previous research has focused on effects in response tendencies. We investigated syntactic priming effects simultaneously in response tendencies and response latencies for active and passive transitive sentences in a picture description task. In Experiment 1, there were priming effects in response tendencies for passives and in response latencies for actives. However, when participants' pre-existing preference for actives was altered in Experiment 2, syntactic priming occurred for both actives and passives in response tendencies as well as in response latencies. This is the first investigation of the effects of structure frequency on both response tendencies and latencies in syntactic priming. We discuss the implications of these data for current theories of syntactic processing

Field theory of scaling lattice models. The Potts antiferromagnet

In contrast to what happens for ferromagnets, the lattice structure participates in a crucial way to determine existence and type of critical behaviour in antiferromagnetic systems. It is an interesting question to investigate how the memory of the lattice survives in the field theory describing a scaling antiferromagnet. We discuss this issue for the square lattice three-state Potts model, whose scaling limit as T->0 is argued to be described exactly by the sine-Gordon field theory at a specific value of the coupling. The solution of the scaling ferromagnetic case is recalled for comparison. The field theory describing the crossover from antiferromagnetic to ferromagnetic behaviour is also introduced.Comment: 11 pages, to appear in the proceedings of the NATO Advanced Research Workshop on Statistical Field Theories, Como 18-23 June 200

Barriers to participation in a placebo-surgical trial for lumbar spinal stenosis

© 2019 Background: Placebo-controlled trials are an important tool when assessing the efficacy of spinal surgical procedures. The most common spinal surgical procedure in older adults is decompression for lumbar spinal stenosis. Before conducting a placebo-surgical trial on decompression surgery, an investigation of patients’ willingness to participate in a placebo-controlled trial of decompression surgery and barriers to participation were explored. Materials: An online survey. Methods: Descriptive analyses of demographic and clinical data, and participants' willingness to participate in a placebo-surgical trial. Logistic regression was used to examine potential predictors of willingness to participate. Two independent researchers performed a coded framework analysis of patients’ barriers to participation. Results: 68 patients were invited and 63 participants completed the survey (91.3% response, mean (SD) age 69.5 (10.9) years, 52% females), 71% suffered from moderate to very severe pain. Ten participants (15.9%) were willing to participate in a placebo-controlled trial. Being married was associated with decreased odds of participating (OR: 0.2; 95% CI, 0.05 to 0.8; P = 0.03), while the main barriers were a lack of information about the procedure, reassurance of a positive outcome with participation, and concerns about the risks and benefits of placebo surgery. Conclusions: A minority of patients with lumbar spinal stenosis were willing to participate in a placebo-controlled trial of surgery. The identified barriers indicate that educating eligible patients about: the need for placebo-surgical trials, the personal risks and benefits of participation, and the importance and potential benefits of placebo trials to others, may be crucial to ensure adequate recruitment into the placebo-controlled surgical trial. Conclusions should be read cautiously however, given the small sample size present in this study

Heterogeneities in leishmania infantum infection : using skin parasite burdens to identify highly infectious dogs

Background: The relationships between heterogeneities in host infection and infectiousness (transmission to arthropod vectors) can provide important insights for disease management. Here, we quantify heterogeneities in Leishmania infantum parasite numbers in reservoir and non-reservoir host populations, and relate this to their infectiousness during natural infection. Tissue parasite number was evaluated as a potential surrogate marker of host transmission potential. Methods: Parasite numbers were measured by qPCR in bone marrow and ear skin biopsies of 82 dogs and 34 crab-eating foxes collected during a longitudinal study in Amazon Brazil, for which previous data was available on infectiousness (by xenodiagnosis) and severity of infection. Results: Parasite numbers were highly aggregated both between samples and between individuals. In dogs, total parasite abundance and relative numbers in ear skin compared to bone marrow increased with the duration and severity of infection. Infectiousness to the sandfly vector was associated with high parasite numbers; parasite number in skin was the best predictor of being infectious. Crab-eating foxes, which typically present asymptomatic infection and are non-infectious, had parasite numbers comparable to those of non-infectious dogs. Conclusions: Skin parasite number provides an indirect marker of infectiousness, and could allow targeted control particularly of highly infectious dogs

Five-year review of an international clinical research-training program

The exponential increase in clinical research has profoundly changed medical sciences. Evidence that has accumulated in the past three decades from clinical trials has led to the proposal that clinical care should not be based solely on clinical expertise and patient values, and should integrate robust data from systematic research. As a consequence, clinical research has become more complex and methods have become more rigorous, and evidence is usually not easily translated into clinical practice. Therefore, the instruction of clinical research methods for scientists and clinicians must adapt to this new reality. To address this challenge, a global distance-learning clinical research-training program was developed, based on collaborative learning, the pedagogical goal of which was to develop critical thinking skills in clinical research. We describe and analyze the challenges and possible solutions of this course after 5 years of experience (2008-2012) with this program. Through evaluation by students and faculty, we identified and reviewed the following challenges of our program: 1) student engagement and motivation, 2) impact of heterogeneous audience on learning, 3) learning in large groups, 4) enhancing group learning, 5) enhancing social presence, 6) dropouts, 7) quality control, and 8) course management. We discuss these issues and potential alternatives with regard to our research and background

Optimization of K-edge subtraction imaging using a pixellated spectroscopic detector

Conventional K-edge subtraction imaging is based around the acquisition of two separate images at energies respectively below and above the K-edge of a contrast agent. This implies increased patient dose with respect to a conventional procedure and potentially incorrect image registration due to patient motion. © 2012 IEEE

Evaluation of rK39 rapid diagnostic tests for canine visceral leishmaniasis : longitudinal study and meta-analysis

Canine visceral leishmaniasis is a vector-borne disease caused by the intracellular parasite Leishmania infantum. It is an important veterinary disease, and dogs are also the main animal reservoir for human infection. The disease is widespread in the Mediterranean area, and parts of Asia and South and Central America, and is potentially fatal in both dogs and humans unless treated. Diagnosis of canine infections requires serological or molecular tests. Detection of infection in dogs is important prior to treatment, and in epidemiological studies and control programmes, and a sensitive and specific rapid diagnostic test would be very useful. Rapid diagnostic tests (RDTs) have been developed, but their diagnostic performance has been reported to be variable. We evaluated the sensitivity of a RDT based on serological detection of the rK39 antigen in a cohort of naturally infected Brazilian dogs. The sensitivity of the test to detect infection was relatively low, but increased with time since infection and the severity of infection. We then carried out a meta-analysis of published studies of rK39 RDTs, evaluating the sensitivity to detect disease and infection. The results suggest that rK39 RDTs may be useful in a veterinary clinical setting, but the sensitivity to detect infection is too low for operational control programmes

Continuous heating of a giant X-ray flare on Algol

Giant flares can release large amounts of energy within a few days: X-ray emission alone can be up to ten percent of the star's bolometric luminosity. These flares exceed the luminosities of the largest solar flares by many orders of magnitude, which suggests that the underlying physical mechanisms supplying the energy are different from those on the Sun. Magnetic coupling between the components in a binary system or between a young star and an accretion disk has been proposed as a prerequisite for giant flares. Here we report X-ray observations of a giant flare on Algol B, a giant star in an eclipsing binary system. We observed a total X-ray eclipse of the flare, which demonstrates that the plasma was confined to Algol B, and reached a maximum height of 0.6 stellar radii above its surface. The flare occurred around the south pole of Algol B, and energy must have been released continously throughout its life. We conclude that a specific extrastellar environment is not required for the presence of a flare, and that the processes at work are therefore similar to those on the Sun.Comment: Nature, Sept. 2 199