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41.
Listening to music can induce us to tune in to its beat. Previous neuroimaging studies have shown that the motor system becomes involved in perceptual rhythm and timing tasks in general, as well as during preference‐related responses to music. However, the role of preferred rhythm and, in particular, of preferred beat frequency (tempo) in driving activity in the motor system remains unknown. The goals of the present functional magnetic resonance imaging (fMRI) study were to determine whether the musical rhythms that are subjectively judged as beautiful boost activity in motor‐related areas and if so, whether this effect is driven by preferred tempo, the underlying pulse people tune in to. On the basis of the subjects' judgments, individual preferences were determined for the different systematically varied constituents of the musical rhythms. Results demonstrate the involvement of premotor and cerebellar areas during preferred compared to not preferred musical rhythms and indicate that activity in the ventral premotor cortex (PMv) is enhanced by preferred tempo. Our findings support the assumption that the premotor activity increase during preferred tempo is the result of enhanced sensorimotor simulation of the beat frequency. This may serve as a mechanism that facilitates the tuning‐in to the beat of appealing music. Hum Brain Mapp, 2010. © 2009 Wiley‐Liss, Inc.  相似文献   
42.

Background

A failure rate between 20% and 45.5% after retrourethral transobturator sling (RTS) is reported. Recommendations for the management of persistent or recurrent postprostatectomy stress urinary incontinence (SUI) after failed male sling do not exist.

Objective

The aim of this study was the prospective evaluation of the efficacy of repeat RTS (RRTS) in patients after failed first RTS.

Design, setting, and participants

Between March 2007 and August 2009, 35 patients with mild to severe SUI after failed first RTS were treated with a second AdVance sling (American Medical Systems, Minnetonka, MN, USA).

Measurements

Preoperative and postoperative evaluation included daily pad use, 1-hr pad test, postvoiding residual (PVR) urine, uroflowmetry, and quality-of-life (QoL) scores.

Results and limitations

After 6 mo, 45.5% (15 of 33 patients) showed no pad use; 30.3% (10 of 33 patients), one dry “security” pad; 3% (1 of 33 patients), one wet pad; 6.1% (2 of 33 patients), two pads; 3% (1 of 33 patients), pad reduction ≥50%; and 12.1% (4 of 33 patients), treatment failure. After 16.6 mo, 34.5% (10 of 29 patients) showed no pad use; 37.9% (11 of 29 patients), one dry “security” pad; 3.4% (1 of 29 patients), one wet pad; 3.4% (1 of 29 patients), two pads; 10.3% (3 of 29 patients), pad reduction ≥50%; and 10.4% (3 of 29 patients), treatment failure. Daily pad use and pad weight decreased significantly. PVR and uroflowmetry results showed no significant change. QoL improved significantly. Postoperative acute urinary retention was observed in 23.6% of patients.

Conclusions

RRTS is an effective and safe treatment option for the management of SUI after failed first RTS.  相似文献   
43.
Internalization of Staphylococcus aureus in bovine endothelial cells (BEC) is increased by tumor necrosis factor alpha stimulation and NF-κB activation. Because the phosphoinositide-3-kinase (PI3K)-Akt signaling pathway also modulates NF-κB activity, we considered whether the internalization of S. aureus by BEC is associated with the activity of PI3K and Akt. We found a time- and multiplicity of infection-dependent phosphorylation of Akt on Ser473 in BEC infected with S. aureus. This phosphorylation was inhibited by LY294002 (LY), indicating the participation of PI3K. Inhibition of either PI3K with LY or wortmannin, or Akt with SH-5, strongly reduced the internalization of S. aureus. Transfection of BEC with a dominant-negative form of the Akt gene significantly decreased S. aureus internalization, whereas transfection with the constitutively active mutant increased the number of internalized bacterium. Inhibition of PDK1 activity with OSU-03012 did not affect the level of S. aureus internalization, demonstrating that phosphorylation of Akt on Thr308 is not important for this process. Compared to the untreated control, the adherence of S. aureus to the surface of BEC was unaltered when cells were transfected or incubated with the pharmacological inhibitors. Furthermore, Akt activation by internalized S. aureus triggered a time-dependent phosphorylation of glycogen synthase kinase-3α (GSK-3α) on Ser21 and GSK-3β on Ser9 that was partially inhibited with SH-5. Finally, treatment of BEC with LY prior to S. aureus infection inhibited the NF-κB p65 subunit phosphorylation on Ser536, indicating the involvement of PI3K. These results suggest that PI3K-Akt activity is important for the internalization of S. aureus and phosphorylation of GSK-3α, GSK-3β, and NF-κB.  相似文献   
44.
45.
Processing perceptual sequences relies on the motor system, which is able to simulate the dynamics of the environment by developing internal representations of external events and using them to predict the incoming stimuli. Although it has previously been demonstrated that such models may incorporate predictions based on exact stimulus properties and single stimulus dimensions, it is not known whether they can also support abstract predictions pertaining to the level of stimulus categories. This issue was investigated within the present event‐related functional magnetic resonance imaging study, which compared the processing of perceptual sequences of different specificity, namely those in which the sequential structure was based on the order of presentation of individual stimuli (token), and those in which such structure was defined by stimulus categories (type). The results obtained indicate a comparable engagement of the basic premotor–parietal network in processing both specific and categorical perceptual sequences. However, type sequences additionally elicited activations within the lateral prefrontal, occipital and posterior temporal regions that supported categorization in this task context. Introducing sequential deviants into token sequences activated parietotemporal and ventrolateral frontal cortices, whereas a less pronounced overall response, dominated by lateral prefrontal activation, was elicited by violations introduced into type sequences. Overall, the findings obtained suggest that, although forward models in perception may be able to incorporate expectations of lower specificity when compared to the motor domain, such processing is crucially dependent on additional contributions from lateral prefrontal as well as inferior occipital and temporal cortices that support categorization occurring in such a dynamic context.  相似文献   
46.
When we observe an action, we know almost immediately what goal is pursued by the actor. Strikingly, this applies also to pretend action (pantomime), which provides relevant information about the manipulation itself but not about the manipulated objects. The present fMRI study addressed the issue of goal inference from pretend action as compared with real action. We found differences as well as commonalities for the brain correlates of inferring goals from both types of action. They differed with regard to the weights of the underlying action observation network, indicating the exploitation of object information in the case of real actions and manipulation information in the case of pretense. However, goal inferences from manipulation information resulted in a common network for both real and pretend action. Interestingly, this latter network also comprised areas that are not identified by action observation and that might be due to the processing of scene gist and to the evaluation of fit of putative action goals. These findings suggest that observation of pretense emphasizes the requirement to internally simulate the observed act but rule out fundamental differences of how observers cope with real and pretend action.  相似文献   
47.
48.
Heterogeneity in clinical disease course and histopathology complicates the treatment of multiple sclerosis. We detected important differences in neurodegeneration in various subtypes of myelin oligodendrocyte glycoprotein (MOG)-induced optic neuritis. Dark Agouti (DA) rats showed a significantly higher survival of retinal ganglion cells in comparison to Brown Norway rats. After surgical transection of the optic nerve neuronal loss was similar in both rat strains. We identified an increased expression of interleukin 1beta and glial cell line-derived neurotrophic factor in DA rats as the possible mechanism of the observed endogenous neuroprotection in MOG-induced optic neuritis.  相似文献   
49.
To characterize modes of action of substances and their cytotoxic effects Bionas GmbH has developed a new screening system to allow the continuous recording of how an active substance can act (Bionas 2500 analyzing system). In the pharmaceutical industry it is important to acquire as much information as possible about the metabolic effects of an active substance. Most classical pre-clinical studies are very expensive and time-consuming. Often they are so-called end-point tests which require many individual tests before approximate statements can be made about how an effect takes its course. With the Bionas 2500 analyzing system metabolically relevant data including oxygen consumption, acidification rate and the adhesion (cell impedance) of cells can be measured in parallel, online and label-free. Using e.g. ion-sensitive field effect-transistors (ISFET) and electrode structures it is possible to observe metabolic parameters non-invasively and continuously over longer periods of time. The system has already been established for several cell models, cell lines as well as primary cells. It also offers the advantage that regenerative effects can be observed during the same test run.  相似文献   
50.

Background

Non-alcoholic fatty liver disease (NAFLD) represents a major disease burden in the population. While the bidirectional association between NAFLD and diabetes is established, little is known about the association of hepatic iron content and glycaemia. Moreover, analyses of sex-specific effects and of dynamic changes in glycaemia are scarce.

Methods

We investigated 7-year sex-specific trajectories of glycaemia and related traits (HbA1c, fasting glucose, fasting insulin, HOMA-IR, 2-h glucose and cross-sectional 2-h insulin) in a sample from a population-based cohort (N = 365; 41.1% female). Hepatic iron and fat content were assessed by 3T-Magnetic Resonance Imaging (MRI). Two-step multi-level models adjusted for glucose-lowering medication and confounders were applied.

Results

In women and men, markers of glucose metabolism correlated with hepatic iron and fat content. Deterioration of glycaemia was associated with increased hepatic iron content in men (normoglycaemia to prediabetes: beta = 2.21 s−1, 95% CI [0.47, 3.95]). Additionally, deterioration of glycaemia (e.g. prediabetes to diabetes: 1.27 log(%), [0.84, 1.70]) and trajectories of glucose, insulin and HOMA-IR were significantly associated with hepatic fat content in men. Similarly, deterioration of glycaemia as well as trajectories of glucose, insulin and HOMA-IR was significantly associated with increased hepatic fat content in women (e.g. trajectory of fasting insulin: 0.63 log(%), [0.36, 0.90]).

Conclusions

Unfavourable 7-year trajectories of markers of glucose metabolism are associated with increased hepatic fat content, particularly in women, whereas the association with hepatic iron content was less clear. Monitoring changes of glycaemia in the sub-diabetic range might enable early identification of hepatic iron overload and steatosis.  相似文献   
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