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Jiaofen Nan Jixin Liu Guoying Li Shiwei Xiong Xuemei Yan Qing Yin Fang Zeng Karen M. von Deneen Fanrong Liang Qiyong Gong Wei Qin Jie Tian 《PloS one》2013,8(6)
Recent neuroimaging studies have shown local brain aberrations in functional dyspepsia (FD) patients, yet little attention has been paid to the whole-brain resting-state functional network abnormalities. The purpose of this study was to investigate whether FD disrupts the patterns of whole-brain networks and the abnormal functional connectivity could reflect the severity of the disease. The dysfunctional interactions between brain regions at rest were investigated in FD patients as compared with 40 age- and gender- matched healthy controls. Multivariate pattern analysis was used to evaluate the discriminative power of our results for classifying patients from controls. In our findings, the abnormal brain functional connections were mainly situated within or across the limbic/paralimbic system, the prefrontal cortex, the tempo-parietal areas and the visual cortex. About 96% of the subjects among the original dataset were correctly classified by a leave one-out cross-validation approach, and 88% accuracy was also validated in a replication dataset. The classification features were significantly associated with the patients’ dyspepsia symptoms, the self-rating depression scale and self-rating anxiety scale, but it was not correlated with duration of FD patients (p>0.05). Our results may indicate the effectiveness of the altered brain functional connections reflecting the disease pathophysiology underling FD. These dysfunctional connections may be the epiphenomena or causative agents of FD, which may be affected by clinical severity and its related emotional dimension of the disease rather than the clinical course. 相似文献
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Fang Zeng Wei Qin Yue Yang Danhua Zhang Jixin Liu Guangyu Zhou Jinbo Sun Shengfeng Lu Yong Tang Yuan Chen Lei Lan Shuguang Yu Ying Li Xin Gao Qiyong Gong Jie Tian Fanrong Liang 《PloS one》2013,8(7)
Background and Aims
Brain dysfunction in functional dyspepsia (FD) has been identified by multiple neuroimaging studies. This study aims to investigate the regional gray matter density (GMD) changes in meal-related FD patients and their correlations with clinical variables, and to explore the possible influence of the emotional state on FD patients’s brain structures.Methods
Fifty meal-related FD patients and forty healthy subjects (HS) were included and underwent a structural magnetic resonance imaging scan. Voxel-based morphometry analysis was employed to identify the cerebral structure alterations in meal-related FD patients. Regional GMD changes'' correlations with the symptoms and their durations, respectively, have been analyzed.Results
Compared to the HS, the meal-related FD patients showed a decreased GMD in the bilateral precentral gyrus, medial prefrontal cortex (MPFC), anterior cingulate cortex (ACC) and midcingulate cortex (MCC), left orbitofrontal cortex (OFC) and right insula (p<0.05, FWE Corrected, Cluster size>50). After controlling for anxiety and depression, the meal-related FD patients showed a decreased GMD in the bilateral middle frontal gyrus, left MCC, right precentral gyrus and insula (p<0.05, FWE Corrected, Cluster size>50). Before controlling psychological factors, the GMD decreases in the ACC were negatively associated with the symptom scores of the Nepean Dyspepsia Index (NDI) (r = −0.354, p = 0.048, Bonferroni correction) and the duration of FD (r = −0.398, p = 0.02, Bonferroni correction) respectively.Conclusions
The regional GMD of meal-related FD patients, especially in the regions of the homeostatic afferent processing network significantly differed from that of the HS, and the psychological factors might be one of the essential factors significantly affecting the regional brain structure of meal-related FD patients. 相似文献3.
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Biochemistry and cell signaling taught by bacterial effectors 总被引:1,自引:0,他引:1
Bacterial virulence often relies on secreted effectors that modulate eukaryotic signal transduction. Recent studies provide a collection of examples in which bacterial effectors carry out unprecedented posttranslational modifications of key signaling molecules or organize a new signaling network. OspF and YopJ families of effectors use novel modification activities to block kinase phosphoactivation. Targeting of the ubiquitin system by IpaH and Cif/CHBP families provides insights into host ubiquitin signaling. Manipulation of small GTPases by VopS/IbpA and SidM suggests previously underappreciated regulation of signaling. Several other effectors, including SifA and EspG, organize newly discovered signaling networks in membrane trafficking. Studies of these effectors can generate new knowledge in enzyme catalysis and provide new angles for furthering our understanding of biochemical regulation of important signaling pathways. 相似文献
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Liu J Qin W Yuan K Li J Wang W Li Q Wang Y Sun J von Deneen KM Liu Y Tian J 《PloS one》2011,6(10):e23098
Background
The majority of previous heroin cue-reactivity functional magnetic resonance imaging (fMRI) studies focused on local function impairments, such as inhibitory control, decision-making and stress regulation. Our previous studies have demonstrated that these brain circuits also presented dysfunctional connectivity during the resting state. Yet few studies considered the relevance of resting state dysfunctional connectivity to task-related neural activity in the same chronic heroin user (CHU).Methodology/Principal Findings
We employed the method of graph theory analysis, which detected the abnormality of brain regions and dysregulation of brain connections at rest between 16 male abstinent chronic heroin users (CHUs) and 16 non-drug users (NDUs). Using a cue-reactivity task, we assessed the relationship between drug-related cue-induced craving activity and the abnormal topological properties of the CHUs'' resting networks. Comparing NDUs'' brain activity to that of CHUs, the intensity of functional connectivity of the medial frontal gyrus (meFG) in patients'' resting state networks was prominently greater and positively correlated with the same region''s neural activity in the heroin-related task; decreased functional connectivity intensity of the anterior cingulate cortex (ACC) in CHUs at rest was associated with more drug-related cue-induced craving activities.Conclusions
These results may indicate that there exist two brain systems interacting simultaneously in the heroin-addicted brain with regards to a cue-reactivity task. The current study may shed further light on the neural architecture that supports craving responses in heroin dependence. 相似文献7.
Jeffrey W. Warmke Robert A.G. Reenan Peiyi Wang Su Qian Joseph P. Arena Jixin Wang Denise Wunderler Ken Liu Gregory J. Kaczorowski Lex H.T. Van der Ploeg Barry Ganetzky Charles J. Cohen 《The Journal of general physiology》1997,110(2):119-133
The Drosophila para sodium channel α subunit was expressed in Xenopus oocytes alone and in combination with tipE, a putative Drosophila sodium channel accessory subunit. Coexpression of tipE with para results in elevated levels of sodium currents and accelerated current decay. Para/TipE sodium channels have biophysical and pharmacological properties similar to those of native channels. However, the pharmacology of these channels differs from that of vertebrate sodium channels: (a) toxin II from Anemonia sulcata, which slows inactivation, binds to Para and some mammalian sodium channels with similar affinity (K
d ≅ 10 nM), but this toxin causes a 100-fold greater decrease in the rate of inactivation of Para/TipE than of mammalian channels; (b) Para sodium channels are >10-fold more sensitive to block by tetrodotoxin; and (c) modification by the pyrethroid insecticide permethrin is >100-fold more potent for Para than for rat brain type IIA sodium channels. Our results suggest that the selective toxicity of pyrethroid insecticides is due at least in part to the greater affinity of pyrethroids for insect sodium channels than for mammalian sodium channels. 相似文献
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Zongyou Yin Jixin Zhu Qiyuan He Xiehong Cao Chaoliang Tan Hongyu Chen Qingyu Yan Hua Zhang 《Liver Transplantation》2014,4(1)
Graphene has attracted increasing attention due to its unique electrical, optical, optoelectronic, and mechanical properties, which have opened up huge numbers of opportunities for applications. An overview of the recent research on graphene and its derivatives is presented, with a particular focus on synthesis, properties, and applications in solar cells. 相似文献