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991.
Children with attention-deficit hyperactivity disorder (ADHD) often present with activities of daily living (ADL) performance deficits. This study aimed to compare the performance characteristics of children with ADHD to those of controls based on the Do-Eat assessment tool, and to establish the tool's validity. Participants were 23 children with ADHD and 24 matched controls, aged 6–9?years. In addition to the Do-Eat, the Children Activity Scale–Parent (ChAS-P) and the Behavioral Rating Inventory of Executive Function (BRIEF) were used to measure sensorimotor abilities and executive function (EF). Significant differences were found in the Do-Eat scores between children with ADHD and controls. Significant moderate correlations were found between the Do-Eat sensorimotor scores, the ChAS-P and the BRIEF scores in the ADHD group. Significant correlations were found between performance on the Do-Eat and the ChAS-P questionnaire scores, verifying the tool's ecological validity. A single discriminant function described primarily by four Do-Eat variables, correctly classified 95.5% of the study participants into their respective study groups, establishing the tool's predictive validity within this population. These preliminary findings indicate that the Do–Eat may serve as a reliable and valid tool that provides insight into the daily functioning characteristics of children with ADHD. However, further research on larger samples is indicated.  相似文献   
992.
Traumatic intracranial aneurysms are rare lesions, accounting for less than 1% of all intracranial aneurysms. Formation of these lesions after a penetrating missile wound is very unusual, and diagnosis can be difficult due to the presence of associated lesions. In this article, we report a case of a woman who developed a middle cerebral artery aneurysm after a gunshot wound, and discuss potential pitfalls found during diagnostic work‐up.  相似文献   
993.
A wide variety of microorganisms has previously been identified as causes of brain infection. Among them, Listeria monocytogenes has a particular tropism for the central nervous system. To gain knowledge about the immune response elicited by L. monocytogenes in the brain, we used a rat ex vivo organotypic nervous system culture as a model for Listeria infection. Scanning electron microscopy (SEM) revealed that activated microglial cells showing a typical amoeboid morphology are quickly recruited to the surface of the explants after the infection. After bacterial engulfment, these cells appear to act as Trojan horses, releasing the engulfed bacteria inside the brain tissue. We describe cycles of microglial phagocytosis, necrotic cell death and the subsequent removal of cell debris for the first time. Furthermore, we used this ex vivo model to assess the expression profiles of immune relevant genes up to 24 h postinfection by means of q‐PCR‐arrays, finding that a number of inflammation‐promoting genes are upregulated. Shortly after infection by L. monocytogenes, upregulated genes were those that encoded molecules involved in Th1 responses, being the Ccl2 chemokine and members of the interleukin1‐β family the most abundant immunomodulatory signals expressed. After 5 h of infection, L. monocytogenes caused a substantial increase in the expression of TLR1 and TLR2 genes, as well as in several downstream genes of the TLR signaling pathways. © 2013 Wiley Periodicals, Inc.  相似文献   
994.
Pathological gambling develops in up to 8% of patients with Parkinson's disease. Although the pathophysiology of gambling remains unclear, several findings argue for a dysfunction in the basal ganglia circuits. To clarify the role of the subthalamic nucleus in pathological gambling, we studied its activity during economics decisions. We analyzed local field potentials recorded from deep brain stimulation electrodes in the subthalamic nucleus while parkinsonian patients with (n = 8) and without (n = 9) pathological gambling engaged in an economics decision‐making task comprising conflictual trials (involving possible risk‐taking) and non conflictual trials. In all parkinsonian patients, subthalamic low frequencies (2–12 Hz) increased during economics decisions. Whereas, in patients without gambling, low‐frequency oscillations exhibited a similar pattern during conflictual and non conflictual stimuli, in those with gambling, low‐frequency activity increased significantly more during conflictual than during non conflictual stimuli. The specific low‐frequency oscillatory pattern recorded in patients with Parkinson's disease who gamble could reflect a subthalamic dysfunction that makes their decisional threshold highly sensitive to risky options. When parkinsonian patients process stimuli related to an economics task, low‐frequency subthalamic activity increases. This task‐related change suggests that the cognitive‐affective system that drives economics decisional processes includes the subthalamic nucleus. The specific subthalamic neuronal activity during conflictual decisions in patients with pathological gambling supports the idea that the subthalamic nucleus is involved in behavioral strategies and in the pathophysiology of gambling. © 2013 International Parkinson and Movement Disorder Society  相似文献   
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Background

During adolescence, friends are increasingly important for support and values. Do friends also have a long-term impact on suicidality? This study explored the role of friendship problems (e.g., social isolation) and deviant friends during late adolescence on suicidal ideation and behavior 3 years later.

Method

Participants were 295 community adolescents (59 % Mexican-American; 41 % European-American) from the United States. Information about their suicidal ideation and behavior, depression, friendship problems, and deviant friends was collected at baseline and at a 3-year follow-up.

Results

Having deviant friends was a better predictor of suicidality than having friendship problems, with variability by sex and ethnicity. Having deviant friends predicted suicidal ideation among Mexican-American adolescents. Having friends who were disconnected from school was a risk factor for suicidal ideation among European-American adolescents but a protective factor for suicidal behavior among Mexican-American adolescents, especially boys. Depression played more of a mediating role between friendship factors and suicidality for European-American than for Mexican-American adolescents.

Conclusions

This study’s findings suggest an influence of adolescents’ deviant friends on suicidality 3 years later. They also call for the cultural and gender grounding of suicide theory, research and prevention.  相似文献   
998.
Neurodegeneration of the striatum in Huntington disease (HD) is characterized by loss of medium‐spiny neurons, huntingtin nuclear inclusions, reactive gliosis, and iron accumulation. Neuroimaging allows in vivo detection of the macro‐ and micro‐structural changes that occur from presymptomatic stages of the disease (preHD). The aim of our study was to evaluate the reliability of multimodal imaging as an in vivo biomarker of vulnerability and development of the disease and to characterize macro‐ and micro‐structural changes in subcortical nuclei in HD. Macrostructure (T1‐weighted images), microstructure (diffusion tensor imaging), and iron content (R relaxometry) of subcortical nuclei and medial temporal lobe structures were evaluated by a 3 T scanner in 17 preHD carriers, 12 early‐stage patients and 29 matched controls. We observed a volume reduction and microstructural changes in the basal ganglia (caudate, putamen, and globus pallidus) and iron accumulation in the globus pallidus in both preHD and symptomatic subjects; all these features were significantly more pronounced in patients, in whom degeneration extended to the other subcortical nuclei (i.e., thalamus and accumbens). Mean diffusivity (MD) was the most powerful predictor in models explaining more than 50% of the variability in HD development in the caudate, putamen, and thalamus. These findings suggest that the measurement of MD may further enhance the well‐known predictive value of striatal volume to assess disease progression as it is highly sensitive to tissue microimpairment. Multimodal imaging may detect brain changes even in preHD stages. Hum Brain Mapp, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
999.
1000.
The overall aim of this thesis was to study dentofacial morphology in Turner syndrome (TS) versus controls and the influence hereupon from karyotype. One hundred thirty two TS females (5-66 years of age), from G?teborg, Uppsala and Ume? were participating. Cephalometric analysis, cast model analysis concerning palatal height, dental arch morphology and dental crown width were performed. Eighteen primary teeth were analysed in polarized light microscopy, scanning electron microscopy, microradiography and X-ray microanalysis were performed. The TS females were divided according to karyotype into: 1 45,X; 2 45,X/46,XX; 3 isochromosome; 4 other. Compared to healthy females, TS were found to have a flattened cranial base as well as small and retrognathic jaws with a posterior inclination. The maxillary dentoalveolar arch was narrower and longer, while the mandibular dental arch was wider and longer in TS compared to controls. The palatal height did not differ comparing TS and healthy females. The dental crown width was smaller in TS for both permanent and primary teeth. Aberrant elemental composition, prism pattern and lower mineral density were found in TS primary enamel compared to enamel in primary teeth from healthy girls. Turner syndrome karyotype was found having an impact on craniofacial morphology, with the mosaic 45,X/46,XX exhibiting a milder mandibular retrognathism as well as fewer cephalometric variables differing from controls compared to other karyotypes. Also for the dentoalveolar arch morphology the 45,X/46,XX group had fewer variables differing from healthy females. The isochromosome TS group exhibited the smallest dental crown width for several teeth, while 45,X/46,XX hade the largest dental crown with for some teeth and fewer teeth than both 45,X and isochromosomes that differed from controls. Thus, the mosaic 45,X/46,XX seemed to exhibit a milder phenotype, possibly due to presence of healthy 46,XX cell lines.  相似文献   
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