Personality Disorders Revisited: A Newly Proposed Mental Illness.

Personality disorders such as dependent personality disorder (DPD), among others, have shown limited academic development in terms of a more in-depth understanding or subtypes that may exist as a mental illness or associated condition. DPD was first published as a distinct personality disorder in the Diagnostic and Statistical Manual for Mental Disorders, 3rd edition (DSM III) psychiatry manual in 1980. Since its revision in the DSM IIIR in 1987, no significant advancements have been proposed to date. This case study reported a patient with suicidal ideation and offered a new type of DPD to advance personality disorders research. The new subtype of dependent personality disorder has a few key characteristics of the traditional disorder yet reveals features that mirror nearly opposite symptom criteria, making it unique as a distinct subtype or possibly a separate personality disorder of its kind. The case study patient report proposes comorbid diagnoses of adjustment disorder and dependent personality disorder, the altruistic depressive type. Recommendations for further research were made.

Accounting for photophysical processes and specific signal intensity changes in fluorescence-detected sedimentation velocity.

Fluorescence detected sedimentation velocity (FDS-SV) has emerged as a powerful technique for the study of high-affinity protein interactions, with hydrodynamic resolution exceeding that of diffusion-based techniques, and with sufficient sensitivity for binding studies at low picomolar concentrations. For the detailed quantitative analysis of the observed sedimentation boundaries, it is necessary to adjust the conventional sedimentation models to the FDS data structure. A key consideration is the change in the macromolecular fluorescence intensity during the course of the experiment, caused by slow drifts of the excitation laser power, and/or by photophysical processes. In the present work, we demonstrate that FDS-SV data have inherently a reference for the time-dependent macromolecular signal intensity, resting on a geometric link between radial boundary migration and plateau signal. We show how this new time-domain can be exploited to study molecules exhibiting photobleaching and photoactivation. This expands the application of FDS-SV to proteins tagged with photoswitchable fluorescent proteins, organic dyes, or nanoparticles, such as those recently introduced for subdiffraction microscopy and enables FDS-SV studies of their interactions and size distributions. At the same time, we find that conventional fluorophores undergo minimal photobleaching under standard illumination in the FDS. These findings support the application of a high laser power density for the detection, which we demonstrate can further increase the signal quality.