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Objective: To assess the efficacy of phase-weighted imaging in differentiating multiple system atrophy (MSA) from idiopathic Parkinson disease (IPD)., Methods: A phase-weighted sequence was performed covering striatum in 21 patients with MSA, 20 patients with IPD, and 26 age-matched healthy volunteers after conventional brain magnetic resonance imaging examination on a 3.0T magnetic resonance imaging system. An experienced neuroradiologist who were blind to the clinical diagnosis applied region of interest (ROI) on post-processing phase images to measure the phase shift value of bilateral globus pallidus, putamen, and caudate head., Results: The phase shift values at bilateral putamen of MSA group were significantly lower than those of IPD group and control group (P < 0.05), while phase shift values at other locations of MSA group were not statistically different from those of other groups. The phase shift values showed no statistical difference between IPD group and control group at all regions., Conclusion: Quantitative phase-weighted imaging is a useful sequence to reflect the abnormal iron accumulation in brains of patients with movement disorders and is helpful in the differential diagnosis between MSA and IPD.

Objective: To investigate the value of conventional magnetic resonance imaging (MRI) and diffusion weighed imaging (DWI) in the differentiation of hypoxic-ischemic encephalopathy (HIE) and acute bilirubin encephalopathy in neonates., Methods: The MRI findings along with DWI characteristics in 15 neonates with HIE involving basal ganglia and in 18 neonates with acute bilirubin encephalopathy between November 2006 and June 2008 were retrospectively reviewed., Results: On T1WI, only 5 patients presented hyperintensity in the globus pallidus in the HIE group, but 16 in the acute bilirubin encephalopathy group (p<0.01). Nine patients in the HIE group showed hyperintensity in the putamen, but the hyperintensity in the putamen was not found in the acute bilirubin encephalopathy group. The frequency of hyperintensity in the subthalamus in the acute bilirubin encephalopathy group (55.6%) was significantly higher than that in the HIE group (13.3%) (p<0.05). Eight patients in the HIE group showed abnormal signals in the other regions on T1WI, but only two patients in the acute bilirubin encephalopathy group (p<0.05). On DWI, 7 out of 11 patients with HIE presented hyperintensity in the basal ganglia, while all 10 patients of the acute bilirubin encephalopathy group presented normal in the basal ganglia., Conclusions: Conventional MRI along with DWI is useful in differentiating HIE from acute bilirubin encephalopathy in neonates.

Aim: To explore the protective effect of propyl gallate against neuronal injury in the boundary zone of the infarction area in the rat cerebral ischemia-reperfusion model and its possible mechanism., Methods: Transient focal ischemia induced by middle cerebral artery occlusion in the rats was established by ligation of the left internal carotid artery for 2 h. Rats were treated by propyl gallate with different doses (23.5, 47 and 94 micromol x kg(-1)) for three days before operation. Coronal brain sections were collected after 1 , 2, 4, 6, 12 and 24 h of reperfusion, neuronal injury in the boundary zone of the infarction area was evaluated by TUNEL and Nissl staining. The expression of activated Caspase-3, total SAPK/JNK, p38MAPK and their phosphorylation (Thr183/Tyr185, Thr180/Tyr182) was investigated by immunohistochemistry and Western blotting with corresponding antibodies., Results: Although SAPK/JNK immunoreactivity did not increase at each time point in the boundary zone of the infarction area after reperfusion, p-SAPK/JNK immunoreactivity increased significantly at 1 h and then decreased gradually, and p38MAPK immunoreactivity was enhanced at each time point, peaked at 6 h. Expression of p-p38MAPK peaked at 6 h. Activated Caspase-3 immunoreactivity appeared at 6 h in the boundary zone of the infarction area and peaked at 12 h. TUNEL positive neurons were observed at 12 h and became more abundant at 24 h. The number of Nissl positive neurons decreased gradually and apoptosis ratio of neurons peaked at 24 h. Propyl gallate reduced the immunoreactivity of SAPK/JNK, p-SAPK/JNK, p38MAPK and p-p38MAPK markedly at 1 and 6 h. Propyl gallate with doses of 47 and 94 micromol x kg(-1) were more effective., Conclusion: Inhibition on the activation of SAPK/JNK and p38MAPK is the possible protective mechanism of propyl gallate against neuronal injury induced by cerebral ischemia-reperfusion.

Aim: To study the role of epileptic neural networks reestablished in contralateral caudate putamen (CPu)-hippocampus(HPC) by using chronic tetanization of the right corpus callosum (CTRCC)., Methods: Experiments were performed on 50 SD rats under anaesthesia. The left CPu (LCPu) and the left HPC(LHPC) electrographs were synchronously recorded after acute tetanization following CTRCC (60 Hz, 0.4-0.6 mA, 2 s)., Results: (1) In contralateralization to the side implanted interconvertible network inhibition between the CPu and the HPC were induced by combinedly using chronic and acute tetanization of the RCC. (2) Electrographic kindling in the LCPu or in the LHPC was recorded after CTRCC. (3) In case the LCPu or the LHPC electrographs were not kindled after CTRCC, hypsarrhythmia in the LCPu and reduced sharp waves in the HPC were induced b y repetitive tetanization of the RCC once again. Primary afterdischarges in the LCPu or in the LHPC electrographs were evoked by combinedly using chronic and acute tetanization of the RCC., Conclusion: Pathophysiological neural networks in the CPu and in the HPC might be reestablished in another side of hemispheres by chronic over-activation of the right CC, which is related to epileptogenesis. Abnormal interactions between the two functional neural networks might be involved in formation of secondary epileptic focus.