Objective To examine brain regions with a functional connection to posterior cingulate cortex (PCC) in a relapsing-remitting multiple sclerosis (RRMS) group compared with matched control subjects,and to employ resting-state functional MRI (rs-fMRI) to PCC connectivity gathered by investigating synchronic low frequency fMRI signal fluctuations of default mode network with seed-based correlation analysis (SCA).Methods Twenty-seven patients with RRMS (RRMS group) and 27 age-,and sexmatched healthy controls (HC group) were examined by resting-state fMRI,DTI and 3D-T1 on Siemens Trio Tim 3.0T.The fMRI data preprocessing and processing was performed using Data Processing Assistant for Resting-State fMRI Advanced Edition (DPARSFA) based on Matlab 2012a,and PCC (-5,-49,40)was selected as seed.An SCA approach was used to analyze the rs-fMRI data.We examined the differences in SCA-derived connectivity metrics in patients with RRMS and healthy controls,and analyzed correlations between connectivity correlation coefficient of the differences regions and MRI-derived metrics (brain parenchymal fraction,T2 lesion load),as well as clinical metrics (expanded disability status scale,paced auditory serial addition test,and disease duration) of the disease.Results The SCA via functional connectivity of PCC showed that the temporal correlation between the blood-oxygen-level-dependent signals of the default mode network was reliable spatial patterns of activation in patients with RRMS.The lower connectivity in right superior frontal gyrus within default mode network,and higher connectivity in right posterior lobe of cerebellum,right crus of cerebellum,right medial frontal gyrus,right medial occipital gyrus,left precuneus/cingulate gyrus,right angular gyrus and right cingulate gyrus were found in our study.Significant negative-related was observed between the paced auditory serial addition test and functional connectivity in right middle temporal gyrus (0.387 ± 0.216) of RRMS patients (r =-0.59,P =0.001).Significant negative correlation also was observed between the course of disease and functional connectivity in right superior frontal gyrus (0.039 ± 0.293) in patients (r =-0.39,P =0.041).There was no significant correlations between other regions with different functional connectivity and expanded disability status scale,disease duration,or brain atrophy.The connectivity in right superior frontal gyrus,left medial occipital gyrus,left precentral gyrus was decreased; and connectivity in right cerebellum anterior lobe (dentate),right frontal lobe white matter was significantly increased.Significant positive correlation was observed between the course of disease and functional connectivity in left precentral gyrus (-0.924 ± 0.253),right cerebellum anterior lobe (dentate ;0.217 ± 0.208) of RRMS patients (r =0.650,P =0.000;r =0.436,P =0.023),respectively.Conclusion These findings reveal the compensatory mechanism of the brain in response to structural damage,by means of increased activation or synchronization of default mode network,which seems to be finite.

Objective To investigate the small-world property of default mode network in relapsingremitting multiple sclerosis (RRMS) compared with the (matched) healthy control subjects,using a graph theory for resting-state functional network analysis.Methods Twenty four patients with RRMS and 24 age-,and sexmatched healthy controls were exanined with resting-state functional MRI (R-fMRI) and 3D-T1WI on Trio 3.0 Tesla.The R-fMRI data were preprocessed,then 20 regions of interest (ROIs) was defined and extracted from the default mode network.The functional connectivity between a pair of regions was defined as the Pearson's correlation coefficient in the time courses.Graph theoretical analysis was implemented and compared with the property of binary functional network.Further,the relationships were examined between the topological property of functional networks and the clinical parameters.Results In this study,functional network in the default mode network was conducted,and the small-world characteristics were observed in both RRMS and healthy control group.In the range of densities (Dmin:0.01∶0.48 ;Dmin =0.42),compared with healthy control group,RRMS groups had a slightly smaller normalized clustering coefficient (P＞0.05),a slightly larger normalized path length (P＞0.05),and a slightly decrease small-world index (P＞0.05).The left posterior cingulated cortex showed a significantly larger clustering coefficient in RRMS group (P=0.031) on the network threshold at Dmin.The area under a curve (AUC) for clustering coefficient measure curves of the left posterior cingulated cortex (density range of 0.42:0.01:0.48) between two groups were compared.The AUC result was similar to the Dmin result (P=0.031).Negative correlation was observed between the clustering coefficient of left posterior cingulated cortex and the Paced Auditory Serial Addition Test (PASAT) in both the Dmin(P=0.023) and the AUC (P=0.020).Conclusion The default mode network has small-world property in RRMS group.The significantly increased clustering coefficience is observed in the left posterior cingulated cortex,which may be a side effect.

Objective To analyze the efficacy of percutaneous nephrolithotomy (PCNL)combined with ureteroscopy in treatment of renal staghorn calculi. Methods The data of 126 patients with renal staghorn calculi were retrospectively analyzed in the department of urinary surgery of our hospital. All patients were treated with PCNL combined with ureteroscopy. The related data of preoperative, intraoperative and postoperative were recorded and analyzed. Mean-while, 89 patient with renal staghorn calculi treated by PCNL were selected as control group. The related parameters between two groups were compared. Results Compared with control group,the operation time, amount of bleeding and complication rate of PCNL combined with ureteroscopy group were lower(P<0.05), the stone clearance rate of PCNL combined with ureteroscopy group was higher(P<0.05). Among of PCNL combined with ureteroscopy group,27 patients suffered from fever after surgery and 1 patient had hemorrhage. No renal collection system tear or perforation,damaged pleura, bowel and major vessel occurred. 15 patients had residual stones and were treated by two-stage operation. 48 cases were followed up from postoperative 6-36 months and there wasn't stone recurrence. Conclusion PCNL com-bined with ureteroscopy guided by ultrasound is a good choice in treatment of renal staghorn calculi.