Hallucinogen-persisting perception disorder.

A 33-year-old female patient developed a hallucinogen-persisting perception disorder (HPPD) after lysergic acid diethylamide (LSD) abuse for a year at the age of 18. Specifically, she reported after images, perception of movement in her peripheral visual fields, blurring of small patterns, halo effects, and macro- and micropsia. Previous treatment with antidepressants and risperidone failed to ameliorate these symptoms. Upon commencing drug therapy with lamotrigine, these complex visual disturbances receded almost completely. Based on its hypothesized neuroprotective and mood-stabilizing effects, the antiepileptic lamotrigine may offer a promising new approach in the treatment of HPPD.

Predictors of bradycardia during the stimulation phase of electroconvulsive therapy.

OBJECTIVE: Temporary asystole can be detected at various time points during electroconvulsive treatment. We carefully monitored and documented its incidence during stimulation to evaluate currently known and assumed predictors. METHOD: All treatments over a 20-month period in 2 separate institutions were recorded prospectively. Data from 119 patients comprising 720 treatments were suitable for multiple regression analysis. RESULTS: Electrode placement was the most influential determinant. Treatment series using right unilateral placement (64 patients and 291 traces) produced a mean (SD) asystole duration of 5.64 (2.88) seconds (range, 1.21-11.20 seconds), compared to a duration of 0.80 (0.21) seconds (range, 0.47-1.71 seconds) in bifrontal series (55 patients, 429 traces). Multiple regression analysis showed no independent effect of body weight, age, ß-blocker medication, or preexisting heart block. Stimulus dose and succinylcholine dose had no influence in univariate analyses. Cardiac action in bifrontal treatment series was highly predictable using baseline values. During unilateral stimulation, between-subject differences accounted for 79% of the observed variation. CONCLUSIONS: The heart rate during stimulation depends mainly on electrode positioning. A yet unidentified, probably constitutional factor is responsible for the broad range of asystole duration brought about by right unilateral electrode placement. Any assessment using interindividual analysis will therefore be biased as long as that factor remains unknown.

Neuroprotective role of the Reaper-related serine protease HtrA2/Omi revealed by targeted deletion in mice.

The serine protease HtrA2/Omi is released from the mitochondrial intermembrane space following apoptotic stimuli. Once in the cytosol, HtrA2/Omi has been implicated in promoting cell death by binding to inhibitor of apoptosis proteins (IAPs) via its amino-terminal Reaper-related motif, thus inducing caspase activity, and also in mediating caspase-independent death through its own protease activity. We report here the phenotype of mice entirely lacking expression of HtrA2/Omi due to targeted deletion of its gene, Prss25. These animals, or cells derived from them, show no evidence of reduced rates of cell death but on the contrary suffer loss of a population of neurons in the striatum, resulting in a neurodegenerative disorder with a parkinsonian phenotype that leads to death of the mice around 30 days after birth. The phenotype of these mice suggests that it is the protease function of this protein and not its IAP binding motif that is critical. This conclusion is reinforced by the finding that simultaneous deletion of the other major IAP binding protein, Smac/DIABLO, does not obviously alter the phenotype of HtrA2/Omi knockout mice or cells derived from them. Mammalian HtrA2/Omi is therefore likely to function in vivo in a manner similar to that of its bacterial homologues DegS and DegP, which are involved in protection against cell stress, and not like the proapoptotic Reaper family proteins in Drosophila melanogaster.

Molecular breakpoint analysis and relevance of variable mosaicism in a woman with short stature, primary amenorrhea, unilateral gonadoblastoma, and a 46,X,del(Y)(q11)/45,X karyotype.

We report on a 30-year-old woman with short stature, completely female external genitalia, primary amenorrhea, bilateral streak gonads, unilateral gonadoblastoma, and a 46,X,del(Y)(q11)/45,X karyotype. Variable levels of mosaicism were found in blood and cultivated fibroblasts from both the skin and ovaries, with the percentage of the 45,X lineage never exceeding 33%. Fluorescence in situ hybridization (FISH) was performed with alpha satellite centromere region probes of the X and Y chromosomes (DXZ1 and DXZ3) as well as with the unique-sequence, locus-specific, sex-determining region of the Y chromosome gene (SRY) and the DXZ1 probes. Each signal was noted for DXZ1 on the X chromosome and for the Y probes on the marker chromosome. Molecular investigations with a panel of PCR markers spread over the whole Y chromosome indicated a deletion breakpoint between sY 78 (interval 4) and sY 151 (interval 5F). No mutation of the high mobility group-box (HMG-box) of the SRY gene could be found following sequence analysis. The phenotype/genotype correlation demonstrates the broad phenotypic range of low-level 45,X mosaicism with the resultant short stature and external female phenotype, despite the presence of SRY in a high proportion of cells in various tissues.

Rab3D is not required for exocrine exocytosis but for maintenance of normally sized secretory granules.

Rab3D, a member of the Rab3 subfamily of the Rab/ypt GTPases, is expressed on zymogen granules in the pancreas as well as on secretory vesicles in mast cells and in the parotid gland. To shed light on the function of Rab3D, we have generated Rab3D-deficient mice. These mice are viable and have no obvious phenotypic changes. Secretion of mast cells is normal as revealed by capacitance patch clamping. Furthermore, enzyme content and overall morphology are unchanged in pancreatic and parotid acinar cells of knockout mice. Both the exocrine pancreas and the parotid gland show normal release kinetics in response to secretagogue stimulation, suggesting that Rab3D is not involved in exocytosis. However, the size of secretory granules in both the exocrine pancreas and the parotid gland is significantly increased, with the volume being doubled. We conclude that Rab3D exerts its function during granule maturation, possibly by preventing homotypic fusion of secretory granules.

RIM1alpha forms a protein scaffold for regulating neurotransmitter release at the active zone.

Neurotransmitters are released by synaptic vesicle fusion at the active zone. The active zone of a synapse mediates Ca2+-triggered neurotransmitter release, and integrates presynaptic signals in regulating this release. Much is known about the structure of active zones and synaptic vesicles, but the functional relation between their components is poorly understood. Here we show that RIM1alpha, an active zone protein that was identified as a putative effector for the synaptic vesicle protein Rab3A, interacts with several active zone molecules, including Munc13-1 (ref. 6) and alpha-liprins, to form a protein scaffold in the presynaptic nerve terminal. Abolishing the expression of RIM1alpha in mice shows that RIM1alpha is essential for maintaining normal probability of neurotransmitter release, and for regulating release during short-term synaptic plasticity. These data indicate that RIM1alpha has a central function in integrating active zone proteins and synaptic vesicles into a molecular scaffold that controls neurotransmitter release.