Sensorimotor overactivity as a pathophysiologic trait of embouchure dystonia.

BACKGROUND: Embouchure dystonia is a focal task-specific dystonia affecting the complex interplay of lower facial, jaw, and tongue muscles in musicians playing brass or woodwind instruments. Although it is highly disabling for affected patients, little is known about the pathophysiologic basis of this rare movement disorder. METHODS: We therefore studied sensorimotor activation patterns during 2 orofacial motor tasks in brass players with embouchure dystonia by using fMRI. A "dystonia-specific" task involved buzzing at an instrument-specific, fully functional mouthpiece. A "neutral" task involved simply blowing into a tube. RESULTS: Compared with healthy brass players, patients with embouchure dystonia showed significantly increased activation of somatotopic face representations within the bilateral primary sensorimotor cortex and of the bilateral premotor cortex during buzzing at the mouthpiece. Interestingly, a similar activation pattern was present during the neutral task when patients were clinically asymptomatic. CONCLUSION: Sensorimotor overactivity could reflect deficient subcortical and intracortical inhibition as well as abnormal sensorimotor integration and reorganization in musicians with embouchure dystonia. Because this overactivity was also found during the neutral task, it could be a crucial pathophysiologic factor predisposing for the development of orofacial dystonia rather than a mere correlate of dystonic motor output.

[Psychiatric effects and side effects of the alpha-2-antagonist yohimbine: a review of literature and case report]. / Yohimbin, ein Alpha-2-Antagonist: Literaturübersicht zu psychiatrisch relevanten Wirkungen und Nebenwirkungen mit aktuellem Fallbericht.

We describe a 21-year old female patient who had taken the alpha-2-antagonist yohimbine for weight-loss. The patient reported alterations in alcohol- and cocaine-seeking along with changes in defensive behaviour, including suicidal tendencies. Pre-clinical and clinical studies are discussed, which support the hypothesis of a causal relationship. We added an overview of relevant psychiatric effects and side effects of yohimbine.

"Silent event-related" fMRI reveals reduced sensorimotor activation in laryngeal dystonia.

OBJECTIVE: To study with fMRI the pattern of sensorimotor activation in patients with spasmodic dysphonia (laryngeal dystonia) compared to healthy controls. METHODS: The authors performed fMRI measurements during vocal motor tasks in 12 patients with laryngeal dystonia and compared them with those of 12 healthy volunteers. Patients were scanned before (pre) and after (post) treatment with local injections of botulinum toxin (BTX). They examined two different motor tasks: simple vocalization inducing dystonia and whispering without appearance of dystonic symptoms. To avoid movement artifacts with oral motor tasks, the authors used a silent event-related fMRI approach involving noncontinuous sampling with no data acquisition during task performance. RESULTS: They found reduced activation of primary sensorimotor as well as of premotor and sensory association cortices during vocalization in patients with laryngeal dystonia pre-BTX. This was partly observed also during the asymptomatic whispering task. BTX treatment did not result in reversal of reduced cortical activation. CONCLUSION: fMRI signal is reduced in sensorimotor cortices associated with movement of the affected body part in laryngeal dystonia, supporting a dystonic basis for this voice disorder.

Expression of vesicular monoamine transporters, synaptosomal-associated protein 25 and syntaxin1: a signature of human small cell lung carcinoma.

Vesicular monoamine transporters (VMATs) are a prerequisite for the uptake of biogenic amines into intracellular storage organelles, whereas soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs; such as SNAP-25 and syntaxin1) are essential for exocytosis of biogenic amines by neurons and endocrine cells. In this study, we examined whether these proteins exist in high-grade malignant small cell lung carcinomas (SCLCs), large cell carcinomas, adenocarcinomas, and squamous cell carcinomas of the lung. We analyzed two established human SCLC cell lines, one adenocarcinoma cell line, paraffin-embedded tumors (SCLC, n = 25; large cell carcinoma, n = 10; adenocarcinoma, n = 10; squamous cell carcinoma, n = 10), and snap-frozen SCLC samples (n = 2). Using immunocytochemistry, Western blotting, Northern blotting, RT-PCR, and sequencing, we identified VMAT1, VMAT2, SNAP-25, and syntaxin1 in cultured SCLC cells. Immunohistochemistry carried out on paraffin sections revealed that all SCLC tumors express VMAT1, VMAT2, SNAP-25, and syntaxin1. The presence of SNAP-25 and syntaxin1 in SCLC was confirmed by RT-PCR performed with material extracted from paraffin sections. Western blot analysis and RT-PCR carried out with snap-frozen SCLC tumors revealed the presence of SNAREs and VMATs. Immunohistochemistry showed that non-SCLC tumors were negative for SNAREs and VMATs, with the exception of immunostaining for SNAP-25 and syntaxin1 in 3 of 10 adenocarcinomas. Our findings indicate that SCLC cells are endowed with transporters necessary for intracellular storage of biogenic amines and with proteins required for exocytosis of secretory products. These proteins may be used as markers of differentiation of human lung tumors. Moreover, the presence of VMATs provides the basis for a diagnostic application of biogenic amine-derived tracers in positron emission tomography of SCLC tumors.