Simulation of ambulatory electrodermal activity and the handling of low-quality segments

BACKGROUND AND OBJECTIVES

Monitoring electrodermal activity (EDA) in daily life requires effective handling of low-quality segments, which are common in ambulatory EDA data. Although several low-quality handling methods have been implemented, systematic comparison of these methods, which requires a large annotated dataset, is lacking.

METHODS

Therefore, we proposed the simulation of realistic ambulatory EDA data starting from high-quality EDA signals, which were subsequently contaminated with varying concentrations of artifacts. Subsequently, three approaches for handling low-quality data were evaluated regarding the preservation of several EDA-derived features: removing all artifacts, interpolating over removed artifacts, and retaining all artifacts. Specifically, multiple EDA features were assessed, derived from response detection (evaluated using F1, precision, recall) as well as EDA, phasic, and tonic features (assessed using absolute error), by comparing the simulated EDA data with and without the inserted artifacts, using the latter as ground truth.

RESULTS

For response detection, retaining artifacts resulted in the highest F1-scores, while interpolating over removed artifacts achieved the highest F1-scores for the phasic signal. The approaches did significantly differ in the mean error for the phasic but not for the tonic component and raw EDA.

CONCLUSION

This work generated ambulatory EDA datasets of 200 h, containing 0.125 to 3 artifacts per minute, and showed that interpolation over removed artifacts was an effective approach to reconstruct phasic-derived features up to 2 artifacts per minute. The proposed simulation and evaluation methodology, which are easily customizable, offer opportunities for future research to develop and systematically compare signal quality indicators, decomposition methods, and response detectors for processing ambulatory EDA.

Diagnositic value of pelvic enthesitis on MRI of the sacroiliac joints in enthesitis related arthritis

BACKGROUND

To determine the prevalence and diagnostic value of pelvic enthesitis on MRI of the sacroiliac (SI) joints in enthesitis related arthritis (ERA).

METHODS

We retrospectively studied 143 patients aged 6-18 years old who underwent MRI of the SI joints for clinically suspected sacroiliitis between 2006-2014. Patients were diagnosed with ERA according to the International League of Associations for Rheumatology (ILAR) criteria. All MRI studies were reassessed for the presence of pelvic enthesitis, which was correlated to the presence of sacroiliitis on MRI and to the final clinical diagnosis. The added value for detection of pelvic enthesitis and fulfilment of criteria for the diagnosis of ERA was studied.

RESULTS

Pelvic enthesitis was seen in 23 of 143 (16 %) patients. The most commonly affected sites were the entheses around the hip (35 % of affected entheses) and the retroarticular interosseous ligaments (32 % of affected entheses). MRI showed pelvic enthesitis in 21 % of patients with ERA and in 13 % of patients without ERA. Pelvic enthesitis was seen on MRI in 7/51 (14 %) patients with clinically evident enthesitis, and 16/92 (17 %) patients without clinically evident enthesitis. In 7 of 11 ERA-negative patients without clinical enthesitis but with pelvic enthesitis on MRI, the ILAR criteria could have been fulfilled, if pelvic enthesitis on MRI was included in the criteria. There is a high correlation between pelvic enthesitis and sacroiliitis, with sacroiliitis present in 17/23 (74 %) patients with pelvic enthesitis.

CONCLUSIONS

Pelvic enthesitis may be present in children with or without clinically evident peripheral enthesitis. There is a high correlation between pelvic enthesitis and sacroiliitis on MRI of the sacroiliac joints in children. As pelvic enthesitis indicates active inflammation, it may play a role in assessment of the inflammatory status. Therefore, it should be carefully sought and noted by radiologists examining MRI of the sacroiliac joints in children.

The gender gap in mental health service use

PURPOSE

This study examines why men engage less in mental health service use, by studying how gender is performed in interactions, following the doing gender perspective. We hypothesize that seeking help for mental illness may constitute a gendered role conflict among men since help seeking is associated with femininity. Therefore, we expect that men will recommend reliance on self-care options to other men, and in cases in which professional treatment is recommended, they will prefer medication to psychotherapy. We also expect that men will report greater stigmatizing attitudes.

METHODS

The survey Stigma in a Global Context-Belgian Mental Health Study (2009) conducted interviews of a representative sample of the Belgian general population (N = 743). The vignette technique, depicting depressive and schizophrenic symptoms, was used. Multiple linear and logistic models were estimated in SPSS.

RESULTS

In male vignettes, self-care is more likely to be recommended, both by male and female respondents. Men are less likely to acknowledge the helpfulness of psychotherapy and women rate psychotherapy as less helpful when judging a man compared to a woman. Men rate tranquilizers as more helpful for other males than that women do for other females. Furthermore, male respondents seem to ascribe more shame and blame to the situation.

CONCLUSIONS

The gender gap in mental health service use is due not only to men and their negative attitudes toward help seeking, but also to structured social norms that are reconstructed in interactions. Women also contribute to the maintenance of masculinity norms.

Medicalizing versus psychologizing mental illness: what are the implications for help seeking and stigma? A general population study

PURPOSE

This study contrasts the medicalized conceptualization of mental illness with psychologizing mental illness and examines what the consequences are of adhering to one model versus the other for help seeking and stigma.

METHODS

The survey "Stigma in a Global Context-Belgian Mental Health Study" (2009) conducted face-to-face interviews among a representative sample of the general Belgian population using the vignette technique to depict schizophrenia (N = 381). Causal attributions, labeling processes, and the disease view are addressed. Help seeking refers to open-ended help-seeking suggestions (general practitioner, psychiatrist, psychologist, family, friends, and self-care options). Stigma refers to social exclusion after treatment. The data are analyzed by means of logistic and linear regression models in SPSS Statistics 19.

RESULTS

People who adhere to the biopsychosocial (versus psychosocial) model are more likely to recommend general medical care and people who apply the disease view are more likely to recommend specialized medical care. Regarding informal help, those who prefer the biopsychosocial model are less likely to recommend consulting friends than those who adhere to the psychosocial model. Respondents who apply a medical compared to a non-medical label are less inclined to recommend self-care. As concerns treatment stigma, respondents who apply a medical instead of a non-medical label are more likely to socially exclude someone who has been in psychiatric treatment.

CONCLUSIONS

Medicalizing mental illness involves a package deal: biopsychosocial causal attributions and applying the disease view facilitate medical treatment recommendations, while labeling seems to trigger stigmatizing attitudes.

Attitudes toward community mental health care: the contact paradox revisited

Contact with people with mental illness is considered to be a promising strategy to change stigmatizing attitudes. This study examines the underlying mechanisms of the association between contact and attitudes toward community mental health care. Data are derived from the 2009 survey "Stigma in a Global Context-Belgian Mental Health Study", using the Community Mental Health Ideology-scale. Results show that people who received mental health treatment themselves or have a family member who has been treated for mental health problems report more tolerant attitudes toward community mental health care than people with public contact with people with mental illness. Besides, the perception of the effectiveness of the treatment seems to matter too. Furthermore, emotions arising from public contact are associated with attitudes toward community mental health care. The degree of intimacy and the characteristics of the contact relationship clarify the association between contact and attitudes toward community mental health care.

Catastrophic thinking about pain as a predictor of length of hospital stay after total knee arthroplasty: a prospective study

This study prospectively investigates whether catastrophizing thinking is associated with length of hospital stay after total knee arthroplasty. Forty-three patients who underwent primary total knee arthroplasty were included in this study. Prior to their operation all patients were asked to complete the pain catastrophizing scale, and a Western Ontario McMaster Universities Osteoarthritis index. A multiple regression analysis identified pain catastrophizing thinking and age as predictors of hospital stay after total knee arthroplasty. Patients with a higher degree of pain catastrophizing prior to the total knee arthroplasty and those with a higher age have a significantly greater risk for a longer hospital stay. Therefore, the results of this study indicate that the pre-operative level of pain catastrophizing in patients determine, in combination with other variables, the length and inter-individual variation in hospital stay after total knee arthroplasty. Reducing catastrophizing thinking about pain through cognitive-behavioral techniques is likely to reduce levels of fear after total knee arthroplasty. As a result, pain and function immediately post-operative might improve, leading to a decrease in length of hospital stay. Although during the last decades the duration of hospital stay is significantly reduced, this study shows that this can be improved when taking into account the contribution of psychological factors such as pain catastrophizing.

Down-modulation of type 1 interferon responses by receptor cross-competition for a shared Jak kinase

In contrast to the large number of class I and II cytokine receptors, only four Janus kinase (Jak) proteins are expressed in mammalian cells, implying the shared use of these kinases by many different receptor complexes. Consequently, if receptor numbers exceed the amount of available Jak, cross-interference patterns can be expected. We have engineered two model cellular systems expressing two different exogenous Tyk2-interacting receptors. A receptor chimera was generated wherein the extracellular part of the interferon type 1 receptor (Ifnar1) component of the interferon-alpha/beta receptor is replaced by the equivalent domain of the erythropoietin receptor. Despite Tyk2 activation, erythropoietin treatment of cells expressing this erythropoietin receptor/Ifnar1 chimera did not evoke any detectable IFN-type response. However, a dose-dependent interference with signal transduction via the endogenous Ifnar complex was found for STAT1, STAT2, STAT3, Tyk2, and Jak1 activation, for gene induction, and for antiviral activity. In a similar approach, cells expressing the beta1 chain of the interleukin-12 receptor showed a reduced transcriptional response to IFN-alpha as well as reduced STAT and kinase activation. In both model systems, titration of the Tyk2 kinase away from the Ifnar1 receptor chain accounts for the observed cross-interference.

A sensitive and versatile bioassay for ligands that signal through receptor clustering

The induced expression of xanthine-guanine phosphoribosyl transferase (XGPRT) by low concentrations (-2 pg/ml) of interferon-alpha (IFN-alpha) or IFN-beta, in the 2fTPGH cell line caused a 50% cytotoxicity when these cells were grown in medium containing 6-thioguanine. We extended the application of this sensitive, reliable, and easy bioassay to other members of the cytokine family. To activate the IFN signaling pathway, we made receptor chimeras, consisting of the IFN type I receptor intracellular and transmembrane domains, fused to either the interleukin-5 (IL-5) receptors or erythropoietin (Epo) receptor extracellular domains as model systems. 2fTGH cells, stably transfected with these receptor chimeras, responded to very low concentrations of IL-5 or Epo (IC50 values of approximately 15 pg and 3 pg/ml, respectively) and thus can be used as a very sensitive bioassay for both ligands. Background activity of IL-5, Epo, tumor necrosis factor (TNF), IL-6, or leptin on cells that did not carry the receptor chimeras was very low. This methodology can in principle be extended to any ligand that acts via clustering of its receptors.

Dimerization of the interferon type I receptor IFNaR2-2 is sufficient for induction of interferon effector genes but not for full antiviral activity

We constructed chimeric receptors wherein the extracellular domain of the erythropoietin receptor (EpoR) was fused to the transmembrane and intracellular domains of the interferon (IFN) type I receptor subunits, IFNaR1 or IFNaR2-2. Transfection into 2fTGH and Tyk2-deficient 11,1 cells showed that EpoR/IFNaR2-2 alone was able to transduce a signal upon stimulation with erythropoietin (Epo), as judged by induction of the interferon type I-inducible 6-16 promoter. In contrast, protection against infection with encephalomyocarditis virus or vesicular stomatitis virus was reduced or absent, respectively. To further investigate the role of IFNaR1 in the induction of an antiviral state, we analyzed the Epo- versus IFNalpha-induced transcription of a set of genes, involved in antiviral protection. Up to 24 h after stimulation with Epo or IFNalpha, comparable transcription of the p56, dsRNA-dependent protein kinase, 2'-5'A synthetase, and MxA genes was seen. However, at later time points, only in the case of Epo induction, a sharp decrease of mRNA levels was observed. Western blotting analysis of dsRNA-dependent protein kinase showed a similar pattern at the protein level. Taken together, our results imply a role for IFNaR1 in the induction of sustained mRNA and protein levels that are likely required for optimal antiviral activity.