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Objective: To investigate the abnormalities in regional homogeneity of brain activity in patients with diabetic peripheral neuropathy (DPN) using resting-state functional magnetic resonance imaging (rs-fMRI) and explore the association between brain activity changes and DPN., Methods: A regional homogeneity (ReHo) approach was used to compare the local synchronization of rs-fMRI signals among 20 patients with painful DPN, 16 patients with painless DPN, and 16 type 2 diabetic patients without DPN (non-DPN group)., Results: Compared with the those without DPN, the patients with painful DPN showed high ReHo in the left inferior temporal gyrus and the right central posterior gyrus, and low ReHo in the posterior cingulate gyrus, right inferior parietal gyrus, and the left superior parietal gyrus ( P < 0.05);the patients with painless DPN group showed high ReHo in the left inferior temporal gyrus, the right middle temporal gyrus, and the right superior frontal gyrus, and low ReHo in the left thalamus ( P < 0.05).No significant differences in ReHo were found between the patients with painful DPN and painless DPN ( P >0.05)., Conclusions: The patients with DPN have altered ReHo in multiple brain regions and impairment of a default mode network, for which the left temporal gyrus may serve as a functional compensatory brain area. ReHo disturbance in the central right posterior gyrus may play a central role in the pain symptoms associated with painful DPN.

Objective: As an ill-defined syndrome consisting of heterogeneous neurological symptoms and high serum antithyroid antibody titers, Hashimoto's encephalopathy typically responds to steroids. More serial clinical studies are required to characterize the clinical, laboratory and imaging features and outcomes., Methods: We analyzed retrospectively the clinical, laboratory, and imaging features and outcomes of 15 consecutive patients with Hashimoto's encephalopathy diagnosed at our hospital from 2005 to 2011., Results: Cognitive impairment (11/15) and psychiatric symptoms (5/15) were the most frequent manifestations. Seizure (4/15) and myoclonus (1/15) were less common than previously described. Three (3/15) patients showed abnormal signals in hippocampus or temporal lobe related to memory disorders. Among 10 patients on steroid therapy, there were recovery (n = 5), improvement with residual deficits (n = 2) and relapse or no effect (n = 3). Among 5 patients on non-steroid, there were stable remission with antiepileptic drugs or general neurotrophic therapy (n = 3) and continuous deterioration (n = 2)., Conclusion: Most patients respond well to steroids while someone improves without steroid therapy. In light of its reversible course, we recommend that Hashimoto's encephalopathy should always be considered in the differential diagnosis while evaluating disorders of central nervous system, even disorders those without manifestations of encephalopathy.

Objective: Neuronal circuits involved in the pathophysiology of anxiety are not yet fully understood. We used functional connectivity MRI to explore the characteristic of functional connectivity in anxiety disorders patient and the neural mechanism of this disease. This work was selected as an oral presentation in 2006 ISMRM., Methods: Twenty right-handed subjects were included in this study, and were divided into two groups. The anxiety (P) group (n = 10; 7 male, mean age 42 years) consisted of patients meeting DSM-IV criteria for a principal diagnosis of anxiety disorder. The control (C) group consisted of volunteers free of psychiatric symptoms, and was matched on age and gender (n = 10; 7 male) with the panic patients. The subjects underwent noninvasive functional magnetic resonance imaging while listening actively to (1): emotionally neutral word alternating with no word as the control condition (CN, PN), and (2): threat-related words alternating with emotionally neutral word as the experimental condition (CT, PT). Each word was presented in pseudorandom order in each 16 s block of 12 words of the same type. Eight alternating blocks of neutral words were presented for about 256 s. The subject was only asked to passively listen to each word. All MRI data were obtained on a 1.5-Tesla scanner Data analysis was performed with SPM99 to find significant activations in two tasks for two groups. Based on group t-test, we chose two anatomically defined regions: left superior temporal gyrus (GTs) and right GTs. Then, based on individual t-map, the voxel with the largest t-value within two regions was taken as the subject-specific peak voxel. We define clusters based on faces and edges, but not corners, so each voxel has 18 neighbors. Subject-specific averaged time series were extracted by averaging the time series of 19 voxels. Since healthy control subjects showed no significant activation (corrected, P < 0.05) during processing of anxiety word to neutral word, region of interest during processing of neutral word to no word was used as substitution. The connectivity degree eta(i j) between the node i and the node j is used to identify the change of the functional connectivity associated with differential tasks, which calculated by using the methods that have developed by ourselves. Moreover, we just consider coherence in low-frequency (0-0.15 Hz)., Results: The activation brain regions have been reported in our previous work. Patients were significant different from normal controls on two experiments. The connectivity degree of left Gts and right Gts in two tasks across all subjects was calculated. Comparing during processing neutral word to blank, a significant decrease (P < 0.001) in functional degree was observed during processing of threaten word to neutral word (eta = 0.5636 for CN, eta = 0.555 for CT, eta = 0.5616 for PN, eta = 0.4926 for PT). Especially, the greater decrease connectivity degree was identified for patient group compared with normal control during threat-related words alternating with emotionally neutral word condition. The connectivity degree identifies that functional interactions change with differential task., Conclusion: This result suggests decreased functional connectivity among left superior temporal gyrus and right GTs during processing of anxiety word to neutral word in anxiety patients. This dysfunction may mediate the neural mechanism of this sort of disease.

Objective: To explore the potential mechanism of generalized anxiety disorders (GAD)., Methods: Ten GAD patients and 10 sex- and age-matched healthy persons underwent functional magnetic resonance imaging (fMRI) study in 2 stages by block design: auditory presentation of the stimulation task. In experiment 1 emotionally neutral words were given and then alternated with a no word period for 8 cycles. In experiment 2 emotionally neutral words and threat-related words were given alternately for 8 cycles. The subjects were asked to listen carefully and then judge their subjective feeling in mind. By the end of experiment they were asked to fill in a state anxiety inventory (STAI-S) so as to calculate the STAI-S scores., Results: The mean STI-S score of the patients in the experiment 1 was 57 +/- 5, significantly higher than that of the healthy persons (37 +/- 3, P < 0.01); and the mean STAI-S score in the experiment 2 of the patients was 66 +/- 6, significantly higher than that of the healthy persons (41 +/- 4, P < 0.01). The fMRI findings showed that in the experiment 1 the activated cerebral regions of the 2 groups were mostly overlapped, including bilateral superior temporal gyri (BA22/42) and middle temporal gyri (BA21), premotor areas (B46), and supplementary motor areas (BA6), and cerebellar hemisphere, and left inferior prefrontal gyrus (BA44/45). However, the activation intensity levels (mean T values) of the bilateral superior temporal gyri of the patients were both significantly higher than those of the control (for the left side: P = 0.051, and for the right side: P = 0.035). In addition, activation of the dorsal lateral prefrontal cortex (BA8/9) and bilateral inferior parietal lobules (BA39/40). In the experiment 2 activation of brain areas could be seen only in the patients, including bilateral superior temporal gyri, middle temporal gyri, inferior prefrontal gyri, inferior parietal lobules, anterior motor areas, supplemental motor areas, and anterior cingulate gyri (BA8/24/32), and left dorsal lateral prefrontal cortex. No significantly activated brain area could be shown in the control at the same stringent statistic level (P < 0.01, uncorrected); however, when the threshold value (P value) was reduced to 0.01, the left anterior cingulate gyrus (BA24/32), posterior cingulate gyrus (BA29/30), and inferior parietal lobules (BA40) were all significantly activated., Conclusion: Dysfunction of superior temporal lobe and dorsal prefrontal cortex, characterized by hyperactivity in response to outer stimuli, may play an important role in the psychopathologic mechanism of GAD.

Aim and Methods: Repeated tetanus (60 Hz, 0.4-0.6 mA, 2 s) were delivered into the right and the left dorsal hippocampus (HPC), or into the right and the left medial temporal neocortex (MTNC) respectively to establish chronic temporal lobe epilepsy model in rats. The possible role of the HPC-Entorhinal cortex (EC)-MTNC-Neocortex neural pathway in epileptogenesis was discussed based on observing the abnormalities in behavior and in EEG or depth electrographes and in T2-weighted magnetic resonance images (T2-MRI)., Results: 1. Occurrence of primary, secondary WEDS and kindling effects were higher in the right dorsal HPC experimental group than those in other three experimental groups (P < 0.005, P < 0.001). T2-MRI signal hyperintensity was remarkable in lateral ventricles close to the HPC (P < 0.05), but not in the EC or in the MTNC. 2. These T2-MRI intensity increases were related to behavioral abnormalities in some MTNC-stimulated rats. 3. Asymmetric behavioral abnormalities and T2-MRI changes were observed in the left and the right DHPC-stimulated groups., Conclusion: HPC may be an "origin" for epileptogenesis and EC may play a "gating" role in it.

Objective: To investigate the effects of N-methyl-D-aspartate receptors (NMDAR or NR) and NR1 subunit on mechanism of initiation and development epilepsy of genetically epilepsy-prone rat., Methods: Antisense oligodeoxynucleotices (ODN) techniques, intracerebroventricular injection and experiments in vitro in rat temporal cortex slices were used., Results: An antisense ODN for NR1, or the correspond sense ODN and normal saline was administered intracerebroventricular (i.c.v., 100 micrograms in 10 microliters) once daily, respectively for three days. P77PMC rats with antisense ODN did not display clonic and tonic convulsion, or showed that significantly lowered seizure scores compared to control groups. Moreover, the frequency and amplitude of early seizure-like events (SLEs) and late reccurrent discharges (LRDs), which induced by lowing Mg2+, were reduced in entorhinal cortex of the temporal cortex slice., Conclusion: Our results suggested that NMDA receptors, specifically the NR1 subunit, may participate in the initiation and development of epilepsy of P77PMC rat.