Transdiagnostic psychiatry: Symptom profiles and their direct and indirect relationship with well-being.

BACKGROUND: Heterogeneity and comorbidity in psychiatric disorders are common, however, little is known about the impact on well-being and the role of functional limitations. We aimed to identify transdiagnostic psychiatric symptom profiles and to study their association with well-being and the mediating role of functional limitations in a naturalistic psychiatric patient group. METHODS: We used four disorder-specific questionnaires to assess symptom severity within a sample of 448 psychiatric patients with stress-related and/or neurodevelopmental disorders and 101 healthy controls. Using both exploratory and confirmatory factor analyses we identified transdiagnostic symptom profiles, which we entered into a linear regression analysis to assess their association with well-being and the mediating role of functional limitations in this association. RESULTS: We identified eight transdiagnostic symptom profiles, covering mood, self-image, anxiety, agitation, empathy, non-social interest, hyperactivity and cognitive focus. Mood and self-image showed the strongest association with well-being in both patients and controls, while self-image also showed the highest transdiagnostic value. Functional limitations were significantly associated with well-being and fully mediated the relationship between cognitive focus and well-being. LIMITATIONS: The participant sample consisted of a naturalistic group of out-patients. While this strengthens the ecological validity and transdiagnostic perspective of this study, the patients with a single neurodevelopmental disorder were underrepresented. CONCLUSION: Transdiagnostic symptom profiles are valuable in understanding what reduces well-being in psychiatric populations, thereby opening new avenues for functionally meaningful interventions.

How the brain connects in response to acute stress: A review at the human brain systems level.

The brain's response to stress is a matter of extensive neurocognitive research in an attempt to unravel the mechanistic underpinnings of neural adaptation. In line with the broadly defined concept of acute stress, a wide variety of induction procedures are used to mimic stress experimentally. We set out to review commonalities and diversities of the stress-related functional activity and connectivity changes of functional brain networks in healthy adults across procedures. The acute stress response is consistently associated with both increased activity and connectivity in the salience network (SN) and surprisingly also with increased activity in the default mode network (DMN), while most studies show no changes in the central executive network. These results confirm earlier findings of an essential, coordinating role of the SN in the acute stress response and indicate a dynamic role of the DMN whose function is less clear. Moreover, paradigm specific brain responses have to be taken into account when investigating the role and the within and between network connectivity of these three networks.

Narcolepsy and psychiatry: an evolving association of increasing interest.

Gélineau originally described narcolepsy as a disease with an organic cause. However, the disorder had undeniable emotional triggers and psychiatric-like expressions, and soon a psychiatric etiology of narcolepsy became a seriously considered option. In fact, the psychiatric view dominated scientific thinking for a long time, not necessarily to the benefit of patients. When hypocretin (orexin) defects were proven to be the cause of narcolepsy Gélineau's original disease model was shown to be right. However, the psychiatric symptoms of the disease were not forgotten afterwards, but gained a different significance: as psychiatric expressions of a brain disease. These symptoms, such as anxiety and eating disorders, can be highly debilitating and warrant clinical attention. Here, we describe the role of psychiatry in the history of narcolepsy, showing their evolving association.

Isolation and characterization of highly purified mitochondrial outer membranes of the yeast Saccharomyces cerevisiae (method).

Mitochondrial outer membrane vesicles (OMV) from the yeast Saccharomyces cerevisiae were prepared by osmotic swelling and mechanical disruption of mitochondria that had been isolated at pH 6.0 and purified by density gradient centrifugation. The OMV were obtained in a yield of 1% (protein/protein) with respect to the mitochondria. The OMV were shown to be essentially free of mitochondrial inner membrane protein markers, while contamination with endoplasmic reticulum was around 5% (protein-based). The very low phosphatidylserine synthase activity present in the OMV preparation indicated that contamination with mitochondria-associated membranes (MAM) was negligible. The resistance of the outer membrane protein Tom40 to digestion by trypsin demonstrated the sealed nature and right-side out orientation of the OMV. Analysis of the phospholipid composition revealed that the contents of phosphatidylcholine and phosphatidylinositol are higher and the content of phosphatidylethanolamine is lower in the mitochondrial outer membrane as compared to whole mitochondria. Cardiolipin is largely depleted in the OMV.