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Our recent DNA-microarray and proteomics studies searching for pathways affected both by chronic lithium treatment and by knockout of each of two genes (IMPA1 or Slc5a3) encoding for proteins related to inositol metabolism, indicated up-regulation of mitochondria-related genes and autophagy-related proteins in the frontal cortex. Differently from previously reported observations of aberrant mitochondrial function in bipolar patients which leave a causality relationship between mitochondrial dysfunction and bipolar disorder an open question, the behavioral results of our recent report following rotenone treatment tempt us to speculate that mitochondrial dysfunction predisposes manic behavior and that drugs targeted to ameliorate mitochondrial function are potential preventers of bursting manic episodes. However, the promiscuity of the involvement of mitochondrial dysfunction and impaired autophagy in the pathophysiology of psychiatric and neurodegenerative disorders raises questions regarding the credibility and relevance of these findings.  相似文献   
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Purpose

The present study was conducted to examine if preinsertion lumbar ultrasound scanning helps with performance of spinal puncture, as a tool for decreasing the number of puncture attempts and spinal procedure time and increasing the success rate. We hypothesized that ultrasound can facilitate neuraxial blockade, particularly in pregnant women with difficult topographic anatomy.

Methods

One hundred (50 lean, BMI <30 kg/m2, and 50 obese, BMI ≥30 kg/m2) parturients scheduled for cesarean delivery were divided into ultrasound and control groups. Subarachnoid block was performed with prepuncture ultrasound examination in lean parturients (group 1, n = 25) and in obese parturients (group 2, n = 25), and subarachnoid block was performed without prepuncture ultrasound examination in lean parturients (group 3, n = 25) and in obese parturients (group 4, n = 25). The number of puncture attempts and puncture levels were recorded.

Results

A lower number of puncture attempts and fewer puncture levels were detected in ultrasound (US) groups (p < 0.001). First attempt success rate under US guidance was 92 % in comparison to 44 % using a conventional technique in obese parturients (p < 0.001). In 52 % of the lean patients and in 54.2 % of the obese patients, the intercristal line was at the L3–L4 and at the L2–L3 interspace, respectively. The duration of spinal procedure was shorter in US groups (22 vs. 52 s, p = 0.031). We found a high correlation between ultrasound and needle depth (r = 0.709, p < 0.001).

Conclusions

We found a high level of success in the prepuncture ultrasound-determined insertion point. The ultrasound imaging technique can be a reliable guide to facilitate spinal anesthesia, especially in obese parturients.  相似文献   
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The sequence effect (SE) in Parkinson's disease (PD) is progressive slowing of sequential movements. It is a feature of bradykinesia, but is separate from a general slowness without deterioration over time. It is commonly seen in PD, but its physiology is unclear. We measured general slowness and the SE separately with a computer‐based, modified Purdue pegboard in 11 patients with advanced PD. We conducted a placebo‐controlled, four‐way crossover study to learn whether levodopa and repetitive transcranial magnetic stimulation (rTMS) could improve general slowness or the SE. We also examined the correlation between the SE and clinical fatigue. Levodopa alone and rTMS alone improved general slowness, but rTMS showed no additive effect on levodopa. Levodopa alone, rTMS alone, and their combination did not alleviate the SE. There was no correlation between the SE and fatigue. This study suggests that dopaminergic dysfunction and abnormal motor cortex excitability are not the relevant mechanisms for the SE. Additionally, the SE is not a component of clinical fatigue. Further work is needed to establish the physiology and clinical relevance of the SE. © 2010 Movement Disorder Society.  相似文献   
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