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131.
Introduction: There is no standardized method for examination of facial muscles with ultrasound. The purpose of this study was to identify those facial muscles accessible for reliable identification and to provide reference data. Methods: In healthy subjects all facial muscles were screened for visibility, separation from adjacent muscles, and reliability of landmarks. Bilateral scans of reliable muscles were performed in 40 adult volunteers. Results: Six facial muscles were clearly demarcated with ultrasound. These were: frontalis, orbicularis oculi, orbicularis oris, depressor anguli oris, depressor labii inferioris, and mentalis muscles. Cross-sectional area and muscle thickness showed gender differences and were independently related to age for some muscles. A significant left–right side difference was only seen for the orbicularis oculi muscle in women. Conclusions: These data demonstrate the usefulness of ultrasonography to assess facial muscles and provide reference values that can be applied in the clinical setting. Muscle Nerve 47: 878–883, 2013  相似文献   
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Progressive multifocal leukoencephalopathy is the most common clinical presentation of JC virus (JCV)‐associated central nervous system (CNS) disease and has emerged as a major safety concern in multiple sclerosis patients treated with the monoclonal antibody natalizumab. Here we report clinical, radiological, and histological findings of a case of cerebellar granule cell neuronopathy (GCN), a JCV‐associated CNS disease, so far unreported amongst patients treated with natalizumab. GCN should be considered as a JCV CNS manifestation in patients with newly developed, progressive cerebellar signs under natalizumab treatment, especially in cases where cerebellar atrophy can be visualized by magnetic resonance imaging. Ann Neurol 2013;74:622–626  相似文献   
134.
The aim of this study was to characterize the effect of γ-aminobutyric acid (GABA) in the resting multiunit activity of the vestibular afferents during development using the isolated inner ear of embryonic and postnatal chickens (E15-E21 and P5). GABA (10−3 to 10−5 M; n = 133) and muscimol (10−3M) elicited an increase in the frequency of the basal discharge of the vestibular afferents. We found that GABA action was dose-dependent and inversely related to animal age. Thus, the largest effect was observed in embryonic ages such as E15 and E17 and decreases in E21 and P5. The GABAA receptor antagonists, bicuculline (10−5M; n = 10) and picrotoxin (10−4M; n = 10), significantly decreased the excitatory action of GABA and muscimol (10−3M). Additionally, CNQX 10−6M, MCPG 10−5M and 7ClKyn 10−5M (n = 5) were co-applied by bath substitution (n = 5). Both the basal discharge and the GABA action significantly decreased in these experimental conditions. The chloride channel blocker 9-AC 0.5 mM produced an important reduction in the effect of GABA 10−3 (n = 5) and 10−4M (n = 5). Thus, our results suggest an excitatory role of GABA in the resting activity of the vestibular afferents that can be explained by changes in the gradient of concentration of Cl during development. We show for the first time that the magnitude of this GABA effect decreases at later stages of embryonic and early postnatal development. Taking into account the results with glutamatergic antagonists, we conclude that GABA has a presynaptic action but is not the neurotransmitter in the vestibular afferent synapses, although it could act as a facilitator of the spontaneous activity and may regulate glutamate release. Synapse 67:374–381, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
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Tuberculosis (TB) is one of the most important public health problems around the world. The emergence of multi‐drug‐resistant (MDR) and extensively drug‐resistant (XDR) Mycobacterium tuberculosis strains has driven the finding of alternative anti‐TB targets. In this context, P‐type ATPases are interesting therapeutic targets due to their key role in ion homeostasis across the plasma membrane and the mycobacterial survival inside macrophages. In this review, in silico and experimental strategies used for the rational design of new anti‐TB drugs are presented; in addition, the chemical space distribution based on the structure and molecular properties of compounds with anti‐TB and anti‐P‐type ATPase activity is discussed. The chemical space distribution compared to public compound libraries demonstrates that natural product libraries are a source of novel chemical scaffolds with potential anti‐P‐type ATPase activity. Furthermore, compounds that experimentally display anti‐P‐type ATPase activity belong to a chemical space of molecular properties comparable to that occupied by those approved for oral use, suggesting that these kinds of molecules have a good pharmacokinetic profile (drug‐like) for evaluation as potential anti‐TB drugs.  相似文献   
137.
Journal of NeuroVirology - Progressive multifocal leukoencephalopathy (PML) is a rare demyelinating disease of the CNS caused by the human polyomavirus 2 (JCV). PML predominantly occurs in...  相似文献   
138.

Purpose

To compare task performances of novices and experts using advanced high-definition 3D versus 2D optical systems in a surgical simulator model.

Methods

Fifty medical students (novices in laparoscopy) were randomly assigned to perform five standardized tasks adopted from the Fundamentals of Laparoscopic Surgery (FLS) curriculum in either a 2D or 3D laparoscopy simulator system. In addition, eight experts performed the same tasks. Task performances were evaluated using a validated scoring system of the SAGES/FLS program. Participants were asked to rate 16 items in a questionnaire.

Results

Overall task performance of novices was significantly better using stereoscopic visualization. Superiority of performances in 3D reached a level of significance for tasks peg transfer and precision cutting. No significant differences were noted in performances of experts when using either 2D or 3D. Overall performances of experts compared to novices were better in both 2D and 3D. Scorings in the questionnaires showed a tendency toward lower scores in the group of novices using 3D.

Conclusions

Stereoscopic imaging significantly improves performance of laparoscopic phantom tasks of novices. The current study confirms earlier data based on a large number of participants and a standardized task and scoring system. Participants felt more confident and comfortable when using a 3D laparoscopic system. However, the question remains open whether these findings translate into faster and safer operations in a clinical setting.
  相似文献   
139.

Background

Exploration of cardiometabolic alterations in the pre-adolescent stage is necessary to characterize possible patterns for matabolic syndrome (MetS) in the earliest stages of the life. However, defining specific cutoff points for metabolic and vascular markers represents a complex task in pre-adolescent populations. This study aimed to estimate the prevalence of MetS and its components in children aged 5-9 years old by using the MetS definition for adolescents with the lowest cut-off points, and evaluate its relationship with overweight and socio-demographic determinants.

Methods

A total of 494 children were evaluated. Multivariate models with filtered variables in preliminary univarite analyses were built to find predictive factors of MetS and its components.

Results

The prevalence of MetS was 8.7% in the studied children. Multivariate models showed that age, overweight and low socioeconomic stratum were associated with MetS; low high-density lipoprotein cholesterol was not significantly associated with any variable; high triglycerides were positively associated with age, overweight and inversely associated with kilocalories/day; female gender was the only variable significantly associated with high fasting glucose (inverse association); and age, gender and overweight were significant factors for increased waist circumference. In the case of high blood pressure, no variable was classified to the multivariate analysis.

Conclusion

This study showed disturbing figures regarding cardiometabolic risk in the children based on comparisons with studies in adolescents. Further studies are needed to confirm the utility of the de Ferranti Mets definition in children.
  相似文献   
140.
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