Electrical Brain Stimulation in Treatment-Resistant Obsessive–Compulsive Disorder

Intein-Mediated Protein Engineering for Cell-Based Biosensors

Cell-based sensors provide a flexible platform for screening biologically active targets and for monitoring their interactions in live cells. Their applicability extends across a vast array of biological research and clinical applications. Particularly, cell-based sensors are becoming a potent tool in drug discovery and cell-signaling studies by allowing function-based screening of targets in biologically relevant environments and enabling the in vivo visualization of cellular signals in real-time with an outstanding spatiotemporal resolution. In this review, we aim to provide a clear view of current cell-based sensor technologies, their limitations, and how the recent improvements were using intein-mediated protein engineering. We first discuss the characteristics of cell-based sensors and present several representative examples with a focus on their design strategies, which differentiate cell-based sensors from in vitro analytical biosensors. We then describe the application of intein-mediated protein engineering technology for cell-based sensor fabrication. Finally, we explain the characteristics of intein-mediated reactions and present examples of how the intein-mediated reactions are used to improve existing methods and develop new approaches in sensor cell fabrication to address the limitations of current technologies.

Deep brain stimulation of the nucleus accumbens and bed nucleus of stria terminalis for obsessive-compulsive disorder: a case series

BACKGROUND

Obsessive-compulsive disorder (OCD) is a psychiatric condition defined by the presence of obsessions, compulsions, or both. It has a lifetime prevalence of 2%-3% and causes significant impairment in social and work functioning, as well as a reduced quality of life. Treatment includes pharmacotherapy and psychotherapy, but a significant number of patients fail to respond to treatment. Deep brain stimulation has shown to be a safe and effective procedure for severe, chronic, treatment-resistant OCD, and several surgical targets have been proposed for treatment, including the nucleus accumbens, the anterior limb of the internal capsule, the subthalamic nucleus, the globus pallidus, and the bed nucleus of stria terminalis.

OBJECTIVES

To report the first Italian case series of patients who underwent DBS of 2 distinct targets for OCD: nulceus accumbens and bed nulceus of stria terminalis.

METHODS

Four patients underwent DBS of the nulceus accumbens, and 4 patients underwent DBS of the bed nucleus of stria terminalis.

RESULTS

Six patients showed a significant improvement in OCD symptoms.

CONCLUSIONS

DBS of these 2 structures is a safe and effective procedure for the treatment of severe, refractory OCD.

The nucleus accumbens beyond the anterior commissure: implications for psychosurgery

INTRODUCTION

The nucleus accumbens (Acc) is a basal forebrain structure integrated in the dopaminergic cerebral rewarding circuits and implicated in some neuropsychiatric disorders. It has become a target for deep brain stimulation for some of these disorders when refractory to medical treatment. However, it is controversial as to which target is the best and similar results have been achieved with the stimulation of neighboring structures such as the bed nucleus of the stria terminalis (BNST). Previous studies have established the stereotactic anatomy of the human Acc, but some difficulties remain concerning its precise posterior limit, which is assumed to be at the level of the anterior commissure (AC). It is our purpose to clarify the anatomy of this zone, given the importance of its exact identification in psychosurgery.

METHODS

A total of 16 Acc were collected by autopsy, fixed, dissected, embedded and cut in coronal 5-µm slices. The slices were stained with hematoxylin and eosin, marked with anti-D1 and anti-D2 antibodies and analyzed under a microscope.

RESULTS

The human Acc has the same cellular structure as the dorsal striatum, except in its posterior subcommissural part where voluminous neurons prevail, similar to and contiguous with the BNST.

CONCLUSIONS

The Acc is longer than previously described, with a sub- and postcommissural extension behind the AC, continuous with the BNST.