Voluntary motor drive: possible reduction in Tourette syndrome

Electrophysiologically, Tourette syndrome (TS) is characterized by shortened cortical silent period (CSP), reflecting decreased motor inhibition. However, voluntary versus involuntary aspects of inhibitory functions in TS are not well understood. Hence, investigating voluntary motor drive (VMD) could help to elucidate this issue. A group of 14 healthy adolescents was compared with subjects of same age suffering from TS with (N = 6) and without (N = 6) presence of distal tics. Basic resting and active motor thresholds (RMT and AMT, respectively) as well as suprathreshold transcranial magnetic stimulation-conditioned RMT and AMT were determined during the CSP. The difference between AMT and RMT was considered as VMD quantum. No group-differences were found in RMT or AMT. Subjects with distal tics showed reduced VMD compared to healthy controls while patients without distal tics did not differ from controls. In the second half of CSP, patients with distal tics showed also diminished VMD compared to tic-patients without distal tics. The findings support the notion, that TS shows possible reduction of VMD and is associated with central motor threshold alterations confined to the very motor networks related to the tics observed

Der frühe Beginn der Zwangsstörung

Einleitung: Die vorliegende Untersuchung geht der Fragestellung nach, ob sich eine Zwangsstörung, die bereits im Kindes- bzw. Jugendalter beginnt, von einer Zwangsstörung, die erst im Erwachsenenalter beginnt, hinsichtlich Schweregrad und Symptomatik unterscheidet. Patienten und Methoden: Eine Stichprobe von 370 Patienten mit Zwangsstörung (ICD-10 F42), die sich zwischen 1998 und 2002 stationär in der Psychosomatischen Klinik Windach befanden, wurde in eine Early-Onset-Gruppe (Störungsbeginn ≤15 Jahre) und in eine Late-Onset-Gruppe (Störungsbeginn ≥16 Jahre) aufgeteilt. Die Gruppen wurden über ICD-10-Diagnosen und Y-BOCSWerte verglichen. Ergebnisse: Beim Schweregrad zeigte sich, dass 20,5% der Early-Onset-Gruppe, aber lediglich 8,7% der Late-Onset-Gruppe unter einer «massiven Zwangsstörung» leiden. Bei der Symptomatik zeigte sich, dass die Early-Onset-Gruppe häufiger die Diagnose «Zwangsgedanken und -handlungen gemischt» (76,9%)erhält als die Late-Onset-Gruppe (61,8%). Außerdem nennt die Early-Onset-Gruppe sowohl für die Gegenwart als auch für die Vergangenheit mehr Symptome als die Late-Onset-Gruppe (Gegenwart 8,2 vs. 7,0; Vergangenheit 5,5 vs. 3,9 Symptomgruppen). Weiter ergaben sich inhaltliche Unterschiede der Zwangsgedanken und Zwangshandlungen. Schlussfolgerungen: Early-Onset-Patienten scheinen häufiger von einer massiven Form der Zwangsstörung und einer größeren Symptomvielfalt betroffen zu sein als Late-Onset-Patienten. Ob es sich bei der Zwangsstörung mit Beginn im Kindes- und Jugendalter um einen abgrenzbaren Subtypus handelt, konnte jedoch in dieser Untersuchung nicht eindeutig geklärt werden und bedarf weiterer Forschungen.Introduction: This study investigates if obsessive compulsive disorder with early onset differs in severity and symptomatology from that with late onset. Patients and Methods: A sample of 370 patients with obsessive compulsive disorder (OCD; ICD 10 F42) who received in-patient treatment at the psychosomatic clinic of Windach between 1998 and 2002 were divided into an early-onset group (onset ≤15 years) and a late-onset group (onset ≥16 years). Groups were compared regarding ICD-10 diagnosis and Y-BOCS scores. Results: Considering severity of the disorder 20.5% of the early-onset group but merely 8.7% of the late-onset group suffered from an extreme form of OCD. With respect to symptomatology, the early-onset group was diagnosed with ‘obsessions and compulsions, mixed’ (76.9%) more often than the lateonset group (61.8%). Also, the early-onset group reported a wider variety of symptoms both for the present and for the past than the late-onset group (present 8,2 vs 7.0; past 5.5 vs 3.9 types of symptoms). There were also differences in the content of rumination and types of compulsive rituals. Conclusions: Patients with early-onset OCD seem to be more frequently affected by an extreme form of OCD and to experience a higher variety of symptoms than patients with late-onset OCD. If early-onset OCD can be considered a distinct subtype could not be answered unequivocally by the results of this study. This question needs additional research

Cytokeratin expression during mouse embryonic and early postnatal mammary gland development

Cytokeratins are intermediate filament proteins found in most epithelial cells including the mammary epithelium. Specific cytokeratin expression has been found to mark different epithelial cell lineages and also to associate with putative mammary stem/progenitor cells. However, a comparative analysis of the expression of cytokaratins during embryonic and postnatal mammary development is currently lacking. Moreover, it is not clear whether the different classes of putative mammary stem/progenitor cells exist during embryonic development. Here, we use double/triple-label immunofluorescence and immunohistochemistry to systematically compare the expression of cytokeratin 5 (K5), cytokeratin 6 (K6), cytokeratin 8 (K8), cytokeratin 14 (K14) and cytokeratin 19 (K19) in embryonic and early postnatal mouse mammary glands. We show that K6+ and K8+/K14+ putative mammary progenitor cells arise during embryogenesis with distinct temporal and spatial distributions. Moreover, we describe a transient disconnection of the expression of K5 and K14, two cytokeratins that are often co-expressed, during the first postnatal weeks of mammary development. Finally, we report that cytokeratin expression in cultured primary mammary epithelial cells mimics that during the early stages of postnatal mammary development. These studies demonstrate an embryonic origin of putative mammary stem/progenitor cells. Moreover, they provide additional insights into the use of specific cytokeratins as markers of mammary epithelial differentiation, or the use of their promoters to direct gene overexpression or ablation in genetic studies of mouse mammary development

Visualizing the Effects of rTMS in a Patient Sample: Small N vs. Group Level Analysis

The use of transcranial magnetic stimulation (TMS) to assess changes in cortical excitability is a tool used with increased prevalence in healthy and impaired populations. One factor of concern with this technique is how to achieve adequate statistical power given constraints of a small number of subjects and variability in responses. This paper compares a single pulse excitability measure using traditional group-level statistics vs single subject analyses in a patient population of subjects with focal hand dystonia, pre and post repetitive TMS (rTMS). Results show significant differences in cortical excitability for 4/5 subjects using a split middle line analysis on plots of individual subject data. Group level statistics (ANOVA), however, did not detect any significant findings. The consideration of single subject statistics for TMS excitability measures may assist researchers in describing the variably of rTMS outcome measures

Environmental enrichment has no effect on the development of dopaminergic and GABAergic fibers during methylphenidate treatment of early traumatized gerbils

It is widely believed, that environmental factors play a crucial role in the etiology and outcome of psychiatric diseases such as Attention-Deficit/Hyperactivity Disorder (ADHD). A former study from our laboratory has shown that both methylphenidate (MP) and handling have a positive effect on the dopaminergic fiber density in the prefrontal cortex (PFC) of early traumatized gerbils (Meriones unguiculatus). The current study was performed to investigate if enriched environment during MP application has an additional influence on the dopaminergic and GABAergic fiber densities in the PFC and amygdala in this animal model

Heterosis Is Prevalent for Multiple Traits in Diverse Maize Germplasm

BACKGROUND: Heterosis describes the superior phenotypes observed in hybrids relative to their inbred parents. Maize is a model system for studying heterosis due to the high levels of yield heterosis and commercial use of hybrids. METHODS: The inbred lines from an association mapping panel were crossed to a common inbred line, B73, to generate nearly 300 hybrid genotypes. Heterosis was evaluated for seventeen phenotypic traits in multiple environments. The majority of hybrids exhibit better-parent heterosis in most of the hybrids measured. Correlations between the levels of heterosis for different traits were generally weak, suggesting that the genetic basis of heterosis is trait-dependent. CONCLUSIONS: The ability to predict heterosis levels using inbred phenotype or genetic distance between the parents varied for the different traits. For some traits it is possible to explain a significant proportion of the heterosis variation using linear modeling while other traits are more difficult to predict

Basal cytokeratins and their relationship to the cellular origin and functional classification of breast cancer

Recent publications have classified breast cancers on the basis of expression of cytokeratin-5 and -17 at the RNA and protein levels, and demonstrated the importance of these markers in defining sporadic tumours with bad prognosis and an association with BRCA1-related breast cancers. These important observations using different technology platforms produce a new functional classification of breast carcinoma. However, it is important in developing hypotheses about the pathogenesis of this tumour type to review the nomenclature that is being used to emphasize potential confusion between terminology that defines clinical subgroups and markers of cell lineage. This article reviews the lineages in the normal breast in relation to what have become known as the 'basal-like' carcinomas

The Evolution of Compact Binary Star Systems

We review the formation and evolution of compact binary stars consisting of white dwarfs (WDs), neutron stars (NSs), and black holes (BHs). Binary NSs and BHs are thought to be the primary astrophysical sources of gravitational waves (GWs) within the frequency band of ground-based detectors, while compact binaries of WDs are important sources of GWs at lower frequencies to be covered by space interferometers (LISA). Major uncertainties in the current understanding of properties of NSs and BHs most relevant to the GW studies are discussed, including the treatment of the natal kicks which compact stellar remnants acquire during the core collapse of massive stars and the common envelope phase of binary evolution. We discuss the coalescence rates of binary NSs and BHs and prospects for their detections, the formation and evolution of binary WDs and their observational manifestations. Special attention is given to AM CVn-stars -- compact binaries in which the Roche lobe is filled by another WD or a low-mass partially degenerate helium-star, as these stars are thought to be the best LISA verification binary GW sources.Comment: 105 pages, 18 figure

Color perception deficits in co-existing attention-deficit/hyperactivity disorder and chronic tic disorders

Preliminary findings suggest that color perception, particularly of blue-yellow stimuli, is impaired in attention-deficit/hyperactivity disorder (ADHD) as well as in chronic tic disorders (CTD). However, these findings have been not replicated and it is unclear what these deficits mean for the comorbidity of ADHD + CTD. Four groups (ADHD, CTD, ADHD + CTD, controls) of children with similar age, IQ and gender distribution were investigated with the Farnsworth-Munsell 100 Hue Test (FMT) and the Stroop-Color-Word Task using a factorial design. Color perception deficits, as indexed by the FMT, were found for both main factors (ADHD and CTD), but there were no interaction effects. A preponderance of deficits on the blue-yellow compared to the red-green axis was detected for ADHD. In the Stroop task only the 'pure' ADHD group showed impairments in interference control and other parameters of Stroop performance. No significant correlations between any FMT parameter and color naming in the Stroop task were found. Basic color perception deficits in both ADHD and CTD could be found. Beyond that, it could be shown that these deficits are additive in the case of comorbidity (ADHD + CTD). Performance deficits on the Stroop task were present only in the 'pure' ADHD group. Hence, the latter may be compensated in the comorbid group by good prefrontal capabilities of CTD. The influence of color perception deficits on Stroop task performance might be negligible. © 2007 Springer-Verlag