Guangdong 999 Brain Hospital
Guangdong 999 Brain Hospital
Shen L.,South China Normal University |
Zhang M.,Soochow University of China |
Chen Q.,South China Normal University |
Chen Q.,Guangdong 999 Brain Hospital
Neuropsychologia | Year: 2016
The Poggendorff illusion refers to the phenomenon that the human brain misperceives a diagonal line as being apparently misaligned once the diagonal line is interrupted by two parallel edges, and the size of illusion is negatively correlated with the angle of interception of the oblique, i.e. the sharper the oblique angle, the larger the illusion. This optical illusion can be produced by both real and illusory contour. In this fMRI study, by parametrically varying the oblique angle, we investigated the shared and specific neural mechanisms underlying the Poggendorff illusion induced by real and illusory contour. At the behavioral level, not only the real but also the illusory contours were capable of inducing significant Poggendorff illusion. The size of illusion induced by the real contour, however, was larger than that induced by the illusory contour. At the neural level, real and illusory contours commonly activated more dorsal visual areas, and the real contours specifically activated more ventral visual areas. More importantly, examinations on the parametric modulation effects of the size of illusion revealed the specific neural mechanisms underlying the Poggendorff illusion induced by the real and the illusory contours, respectively. Left precentral gyrus and right middle occipital cortex were specifically involved in the Poggendorff illusion induced by the real contour. On the other hand, bilateral intraparietal sulcus (IPS) and right lateral occipital complex (LOC) were specifically involved in the Poggendorff illusion induced by the illusory contour. Functional implications of the above findings were further discussed. © 2016 Elsevier Ltd.
Jiang Y.,South China Normal University |
Li S.,South China Normal University |
Li Y.,South China Normal University |
Zeng H.,South China Normal University |
And 2 more authors.
Attention, Perception, and Psychophysics | Year: 2016
It has been documented that due to limited attentional resources, the size of the attentional focus is inversely correlated with processing efficiency. Moreover, by adopting a variety of two-dimensional size illusions induced by pictorial depth cues (e.g., the Ponzo illusion), previous studies have revealed that the perceived, rather than the retinal, size of an object determines its detection. It remains unclear, however, whether and how the retinal versus perceived size of a cue influences the process of attentional orienting to subsequent targets, and whether the corresponding influencing processes differ between two-dimensional (2-D) and three-dimensional (3-D) space. In the present study, we incorporated the dot probe paradigm with either a 2-D Ponzo illusion, induced by pictorial depth cues, or a virtual 3-D world in which the Ponzo illusion turned into visual reality. By varying the retinal size of the cue while keeping its perceived size constant (Exp. 1), we found that a cue with smaller retinal size significantly facilitated attentional orienting as compared to a cue with larger retinal size, and that the effects were comparable between 2-D and 3-D displays. Furthermore, when the pictorial background was removed and the cue display was positioned in either the farther or the closer depth plane (Exp. 2), or when both the depth and the background were removed (Exp. 3), the retinal size, rather than the depth, of the cue still affected attentional orienting. Taken together, our results suggest that the retinal size of a cue plays the crucial role in the visuospatial orienting of attention in both 2-D and 3-D. © 2016, The Psychonomic Society, Inc.
Wang A.,Soochow University of China |
Liu X.,Soochow University of China |
Chen Q.,South China Normal University |
Chen Q.,Guangdong 999 Brain Hospital |
Zhang M.,Soochow University of China
Attention, Perception, and Psychophysics | Year: 2016
When attention is oriented to a peripheral cue, the processing of nearby stimuli is facilitated. This brief period of facilitation is followed by a long-lasting inhibitory effect, during which there is a delayed response to stimuli presented at a previously cued location. Although the mechanisms underlying the facilitatory effect of attentional orienting/reorienting in threedimensional (3-D) space have been documented, there is not yet consensus as to how attention orients/reorients in depth during the later inhibitory phase (i.e., inhibition of return [IOR]). In the present study, by incorporating the Posner exogenous cueing paradigm into a virtual 3-Denvironment, we aimed to investigate whether an IOReffect occurs when attention orients and reorients at the uncued depth in the same hemispace, and whether the IOR effects are the same or different when attention orients/reorients along different trajectories in 3-D space. Our results showed asymmetrical spatial IOR effects when attention was oriented/ reoriented at the uncued depth in the same hemispace. Spatial IOR was depth-specific when targets appeared in the near depth plane, whereas itwas not depth-specific when targets appeared in the far depth plane. Apart from these results, we also found that attention oriented/reoriented at the same depth but in a different hemispace experienced a reduction in IOR size, thus indicating that the direction-specific spatial IOR mechanisms when attention orients/reorients along different trajectories are different. Taken together, our results suggest that spatial IOR is not entirely "depth-blind," and that the ecological importance of the 3-D world influences the direction of attentional shifts of spatial IOR in 3-D space. © The Psychonomic Society, Inc. 2016.
Chen D.,Sun Yat Sen University |
Wei X.,Sun Yat Sen University |
Zou J.,Sun Yat Sen University |
Wang R.,Sun Yat Sen University |
And 8 more authors.
Frontiers in Cellular Neuroscience | Year: 2015
Aim: There is evidence suggesting that inflammatory responses play a critical role in the pathogenesis of multiple system atrophy (MSA). Whether inflammatory mediators can be used as reliable biomarkers to detect the severity and progression of MSA remains largely unknown. Methods: We performed a cross-sectional study that included 47 patients with MSA and 50 healthy age-matched controls. Serum levels of homocysteine (Hcy), uric acid (UA), and C-reactive protein (CRP) were measured. These levels positively correlated with the severity of MSA, based on both motor and non-motor symptoms. Several scales were used to rate the severity of MSA, including the Unified multiple system atrophy rating scale, Parkinson’s disease sleep scale, Non-motor Symptoms Scale, the Schwab & England activities of daily living scale, Webster Scale, modified Hoehn and Yahr staging scale, and the Mini-Mental State Examination. Receiver operating characteristic (ROC) curves was applied to map the diagnostic accuracy of MSA against healthy subjects. Results: Compared with healthy subjects, we found that serum Hcy was higher, UA was lower, and CRP levels were unchanged in MSA patients. These findings were especially prominent in male patients. No significant differences of serum Hcy and UA were observed between patients of MSA and PD. Interestingly, there was a significant correlation between Hcy levels and MSA severity such as movement dysfunction, declined cognition, and cardiovascular symptoms. Additionally, the ROCcurveforthe combination of Hcy and UA (AUC 0.736) showed potential diagnostic value in discriminating MSA from healthy subjects. Conclusion: Our findings suggest that the inflammatory mediators Hcy and UA may play important roles in the pathogenesis of MSA. The measurement of serum Hcy and UA levels could then be a useful tool to accurately distinguish MSA from healthy subjects. © 2015 Chen, Wei, Zou, Wang, Liu, Xu, Lu, Wang, Tang, Wang, Jin and Wang.
Yang H.,Guangzhou University |
Cai L.,Guangdong 999 Brain Hospital |
Zhang Y.,Guangzhou University |
Tan H.,First Affiliated Hospital |
And 3 more authors.
Journal of Molecular Diagnostics | Year: 2014
Epidermal growth factor receptor (EGFR) mutations in cerebrospinal fluid (CSF) might be useful predictive markers for EGFR tyrosine kinase inhibitor treatment of intracranial metastatic tumors. In this retrospective study, amplification refractory mutation system (ARMS)-PCR assays were used to investigate the EGFR gene status in 30 lung adenocarcinoma patients with brain metastases. A total of 16 patients tested positive for EGFR-activating mutations in CSF or tumor tissues. These included L858R mutation in exon 21 in six CSF samples and exon 19 deletions in seven CSF samples. EGFR mutations were detected between CSF and primary tumor samples with a 75% positive predictive value (95% CI, 0.45-1.00), 75% negative predictive value (95% CI, 0.51-0.99), 67% sensitivity (95% CI, 0.36-0.97), and 82% specificity (95% CI, 0.59-1.00). Most of the patients who had EGFR mutations in CSF achieved good responses with EGFR-tyrosine kinase inhibitor treatment. In conclusion, ARMS-PCR could be a sensitive method of detecting EGFR mutations in the CSF of patients with lung adenocarcinoma with brain metastases. As such, ARMS-PCR could play an important role in guiding EGFR-tyrosine kinase inhibitor treatments of intracranial tumors and for diagnosing brain metastases in patients with lung adenocarcinoma. © 2014 American Society for Investigative Pathology.
News Article | November 17, 2016
Glioblastoma multiforme remains the most common and highly lethal brain cancer and is known for its ability to relapse. Researchers at The University of Texas MD Anderson Cancer Center have identified a pathway by which cancer cells aggressively spread and grow in the brain, opening up new possibilities for treatment. Study findings were published in the Nov. 17 online version of Cell. Co-authors included Baoli Hu, Ph.D., senior research scientist, Y. Alan Wang, Ph.D., associate professor, and Ronald A. DePinho, M.D., professor, all of Cancer Biology, and Qianghu Wang Ph.D., Bioinformatics and Computational Biology. "The poor prognosis of glioblastoma relates to the near universal recurrence of tumors despite robust treatment including surgery, radiotherapy and chemotherapy," said Hu. "Our study shows the potential for a new therapeutic strategy based on targeting the mechanisms allowing glioma to re-grow aggressively in the brain." Hu and his colleagues developed a glioblastoma model to locate glioma stem cells, which, like all stem calls, have the ability to become other cell types. The researchers further found that the gene, WNT5A, when activated, allowed glioma stem cells to transition, leading to invasive tumor growth. "We uncovered a process by which glioma stem cells mediated by the WNT5A gene become endothelial-like cells," said Hu. "These new cells known as GdECs, recruit existing endothelial cells to form a niche supporting the growth of invasive glioma cells away from the primary tumor, and often leading to satellite "lesions" and disease recurrence." Clinical data revealed higher WNT5A and GdECs expression in these satellite lesions and recurrent tumors than was observed in the primary tumors, affirming the tie between WNT5A-mediated stem cell differentiation and glioma cell spread throughout the brain, and contributing to the cancer's lethalness. The study established WNT5A as a key factor in glioma stem cells transitioning to GdECs. The team believes this opens up the possibility for a new therapeutic strategy for patients with glioblastoma. Recent clinical data show the FDA-approved drug, bevacizumab, did not benefit patients as a first line treatment of recurrent glioblastoma by targeting vascular endothelial growth factors (VEGF). With this new information, the study team proposes an additional therapeutic approach targeting WNT5A and VEGF signaling pathways for recurrent glioblastoma. "Our preliminary data show that bevacizumab may increase WNT5A-mediated GdECs differentiation and recruitment of existing endothelial cells resulting in no proven benefit to patients with glioblastoma" said Hu. "This new strategy should improve the outcome of brain cancer patients undergoing VEGF therapy, by limiting new tumor growth and invasion, and disease recurrence," said Hu. MD Anderson study team members included Y. Alan Wang, Ph.D., Sujun Hua, Ph.D., Charles-Etienne Sauvé, Derrick Ong, Ph.D., Zheng Lan, Ph.D., Yan Wing Ho, Ph.D., Marta Monasterio, Ph.D., Xin Lu, Ph.D., Pingna Deng, Guocan Wang, Ph.D., Wen-Ting Liao, Ph.D., Denise Spring, Ph.D., Jian Hu, Ph.D., and Ronald DePinho, M.D., all of Cancer Biology; Roeland Verhaak, Ph.D., Bioinformatics and Computational Biology; Jianhua Zhang, Ph.D., and Lynda Chin, M.D., Genomic Medicine; Yi Zong, Ph.D., Epigenetics and Molecular Carcinogenesis; Zhi Tan, Experimental Therapeutics; Lynda Corley and Gregory Fuller, M.D., Ph.D., Pathology; and Erik Sulman, M.D., Ph.D., Radiation Oncology. Other participating institutions included Dana-Farber Cancer Institute, Boston; Nanjing Medical University, Nanjing, China; Guangdong 999 Brain Hospital, Guangzhou, China; the Fondazione IRCCS Istituto Neurologico C. Besta, Milan; and the University of California, San Francisco. The study was funded by National Institutes of Health (P50 CA097257, 2P50CA127001, 5P01CA095616, and P30CA16672).
Huang S.,South China Normal University |
Li Y.,South China Normal University |
Zhang W.,Guangdong 999 Brain Hospital |
Zhang B.,Guangzhou University |
And 4 more authors.
Journal of Neuroscience | Year: 2015
Multisensory information competes for preferential access to consciousness. It remains unknown what neural processes cause one particular modality to win multisensory competition and eventually dominate behavior. Thus, in a paradigm in which human participants sought to make simultaneous auditory and visual detection responses, we sought to identify prestimulus and poststimulus neural signals that were associated with auditory and visual dominance on each trial. Behaviorally, visual detection responses preceded auditory responses more frequently than vice versa. Even when visual responses were preceded by auditory responses, they recovered more quickly from previous responses, indicating the dominance of vision over audition. Neurally, visual precedence was associated with increased prestimulus activity in the prefrontal cortex and reduced prestimulus activity in the default-mode network, and increased poststimulus connectivity between the prefrontal cortex and the visual system. Moreover, the dorsal visual stream showed not only increased activity in post-perceptual phases but also enhanced connectivity with the sensorimotor cortex, indicating the functional role of the dorsal visual stream in prioritizing the flow of visual information into the motor system. In contrast, auditory precedence was associated with increased prestimulus activity in the auditory cortex and increased poststimulus neural coupling between the auditory and the sensorimotor cortex. Finally, whenever one modality lost multisensory competition, the corresponding sensory cortex showed enhanced connectivity with the default-mode network. Overall, the outcome of audiovisual competition depended on dynamic interactions between sensory systems and both the fronto-sensorimotor and the default-mode network. Together, these results revealed both the neural causes and the neural consequences of visual and auditory dominance during multisensory competition. © 2015 the authors.
Wang J.,South China Normal University |
Qiu S.,Southern Medical University |
Xu Y.,South China Normal University |
Liu Z.,Southern Medical University |
And 6 more authors.
Clinical Neurophysiology | Year: 2014
Objective: Temporal lobe epilepsy (TLE) is one of the most common forms of drug-resistant epilepsy. Previous studies have indicated that the TLE-related impairments existed in extensive local functional networks. However, little is known about the alterations in the topological properties of whole brain functional networks. Method: In this study, we acquired resting-state BOLD-fMRI (rsfMRI) data from 26 TLE patients and 25 healthy controls, constructed their whole brain functional networks, compared the differences in topological parameters between the TLE patients and the controls, and analyzed the correlation between the altered topological properties and the epilepsy duration. Results: The TLE patients showed significant increases in clustering coefficient and characteristic path length, but significant decrease in global efficiency compared to the controls. We also found altered nodal parameters in several regions in the TLE patients, such as the bilateral angular gyri, left middle temporal gyrus, right hippocampus, triangular part of left inferior frontal gyrus, left inferior parietal but supramarginal and angular gyri, and left parahippocampus gyrus. Further correlation analysis showed that the local efficiency of the TLE patients correlated positively with the epilepsy duration. Conclusion: Our results indicated the disrupted topological properties of whole brain functional networks in TLE patients. Significance: Our findings indicated the TLE-related impairments in the whole brain functional networks, which may help us to understand the clinical symptoms of TLE patients and offer a clue for the diagnosis and treatment of the TLE patients. © 2014 International Federation of Clinical Neurophysiology.
Wang Y.,Jinan University |
Jia Y.,Jinan University |
Chen X.,Guangdong 999 Brain Hospital |
Ling X.,Jinan University |
And 3 more authors.
Journal of Psychopharmacology | Year: 2012
An excess of glucocorticoids has been associated with hippocampal pathology in major depressive disorder (MDD). However, the relationships between depression, hippocampal structure and function, and cortisol levels are unclear, and the effects of antidepressant treatment on the measures are not well studied. For this study, 26 first-episode, treatment-naive, non-late-life adult depressed patients and 13 healthy controls were enrolled. Subjects underwent proton magnetic resonance spectroscopy (1H MRS) to obtain metabolite levels from the bilateral hippocampus. Patients with MDD were treated with serotonergic-noradrenergic reuptake inhibitor duloxetine for 12 weeks. After the 12-week period, all subjects with MDD underwent 1H MRS again. Morning serum cortisol levels also were measured both before and after antidepressant treatment. Comparison of baseline values indicated that there were no significant differences in any of the metabolite ratios (N-acetyl aspartate/creatine (NAA/Cr) and choline (Cho)/Cr) in the bilateral hippocampus. After treatment, NAA/Cr ratios increased significantly in the right hippocampus compared with pre-treatment values. There was no correlation between morning serum cortisol levels and bilateral hippocampal NAA/Cr or Cho/Cr in patients with MDD. These findings suggest that there are unaltered hippocampal metabolites in the early stage of MDD. Antidepressant treatment may affect hippocampal NAA levels in patients with MDD. In addition, the results do not support cortisol-mediated hippocampal neurotoxicity as the major etiological mechanism. © The Author(s) 2012.
Li X.,Guangdong 999 Brain Hospital |
Wang Y.,Guangdong 999 Brain Hospital
Neurological Sciences | Year: 2014
Here, we present a rare case of a lateral medullary infarction with ipsilateral hemiparesis, lemniscal sensation loss and hypoglossal nerve palsy. In this case, we proved Opalski's hypothesis by diffusion tensor tractography that ipsilateral hemiparesis in a medullary infarction is due to the involvement of the decussated corticospinal tract. We found that the clinical triad of ipsilateral hemiparesis, lemniscal sensation loss and hypoglossal nerve palsy, which had been regarded as a variant of medial medullary syndrome, turned out to be caused by lateral lower medullary infarction. Therefore, this clinical triad does not imply the involvement of the anteromedial part of medulla oblongata, when it is hard to distinguish a massive lateral medullary infarction from a hemimedullary infarction merely from MR images. At last, we suggest that hyperreflexia and Babinski's sign may not be indispensable to the diagnosis of Opalski's syndrome and we propose that "hemimedullary infarction with ipsilateral hemiparesis" is intrinsically a variant of lateral medullary infarction. © 2014 Springer-Verlag.