Metacognitive beliefs in obsessive-compulsive patients: A comparison with healthy and schizophrenia participants

Introduction. Distorted metacognitive beliefs are increasingly considered in theoretical models of obsessive-compulsive disorder (OCD). However, so far no consensus has emerged regarding the specific metacognitive profile of OCD.

Methods. Participants with OCD (n=55), schizophrenia (n=39), and nonclinical controls (n=49) were assessed with the Metacognitions Questionnaire (MCQ-30).

Results. Except for positive beliefs about worry, both patient samples exceeded nonclinical controls on all MCQ subscales. The MCQ “need to control thoughts” and “negative beliefs about uncontrollability and danger” subscales showed strong correlations with obsessions, and scores in the former scale were elevated in hallucinators. In contrast to several prior studies, “cognitive confidence” was related neither to core OCD nor to schizophrenia symptomatology.

Conclusions. Notwithstanding large pathogenetic differences between OCD and schizophrenia, findings suggest that obsessions and hallucinations may share a common metacognitive pathway. Need to control thoughts and dysfunctional beliefs about the malleability of worries may represent critical prerequisites for the two phenomena to emerge.     

The inferiority complex in paranoia readdressed: A study with the Implicit Association Test

Introduction. It has been theorised that patients with persecutory delusions display a lack of covert self‐esteem (formerly termed the ‘inferiority complex’), while at the same time displaying normal or even heightened levels of explicit self‐esteem. However, the empirical basis for this assumption is inconsistent.

Methods. In view of apparent shortcomings of prior studies to assess implicit self‐esteem, the Implicit Association Test was utilised to readdress this theory. The Rosenberg scale served as an index of overt self‐esteem. A total of 23 schizophrenic patients, 13 of whom showed current symptoms of persecutory delusions, participated in the study; 41 healthy and 14 depressed participants served as controls.

Results. Schizophrenic patients showed decreased levels of both implicit and explicit self‐esteem relative to healthy controls. In line with recent studies, patients with current ideas of persecutory delusions displayed greater explicit self‐esteem than nonparanoid patients.

Conclusions. The present study lends partial support for the notion that persecutory delusions serve as a defence against low implicit self‐esteem, although the explicit self‐esteem of these patients is still lower than in normal participants. Apart from abnormalities of attributional style, which have been assumed to convert low into high self‐esteem, the assumption that a ‘feeling of personal significance’ heightens self‐esteem in paranoid schizophrenia deserves further consideration.     

Multi-modular bone healing assessment in a randomized controlled clinical trial of root-end surgery with the use of leukocyte- and platelet-rich fibrin and an occlusive membrane

Clinical Oral Investigations - The aim of this study was to assess in a multi-modular manner the bone healing 1 year post root-end surgery (RES) with leukocyte- and platelet-rich fibrin...     

Retroviral infection and selection of culture-derived platelets allows study of the effect of transgenes on platelet physiology ex vivo and on thrombus formation in vivo

Background- We recently reported the development of culture-derived (CD) platelets with the aim to express any protein of interest in these platelets. We now report a specific protocol of retroviral infection into the progenitor cells and subsequent selection, which allows to generate large amounts of highly homogenous transgene-expressing CD platelets and to study transgene function rapidly and reliably at large-scale ex vivo and in vivo settings. METHODS AND RESULTS: After retroviral infection and selection, the activation-dependent expression profile of surface markers, aggregation, and granule release were investigated. The function of transgene-expressing CD platelets, the precursor cells of which had been retrovirally infected, compared well to noninfected CD platelets or freshly isolated platelets. Hence, the retroviral infection protocol did not alter platelet physiology. In contrast, adenoviral infection of precursors to CD platelets resulted in marked functional alterations that obviated their use in analytic experiments. Additionally, sufficient amounts of selected CD platelets were generated to warrant intravenous injections into living mice. This approach permitted study of their adhesive profile at endothelial lesions and their effect on thrombus formation in vivo by intravital videofluorescence microscopy. CONCLUSIONS: The novel selection method allowed us to produce recombinant transgene-expressing platelets in sufficient amounts to study genetically modified platelets in vitro and in vivo.