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1.  Shear Modulus Estimation on Vastus Intermedius of Elderly and Young Females over the Entire Range of Isometric Contraction 
PLoS ONE  2014;9(7):e101769.
Elderly people often suffer from sarcopenia in their lower extremities, which gives rise to the increased susceptibility of fall. Comparing the mechanical properties of the knee extensor/flexors on elderly and young subjects is helpful in understanding the underlying mechanisms of the muscle aging process. However, although the stiffness of skeletal muscle has been proved to be positively correlated to its non-fatiguing contraction intensity by some existing methods, this conclusion has not been verified above 50% maximum voluntary contraction (MVC) due to the limitation of their measurement range. In this study, a vibro-ultrasound system was set up to achieve a considerably larger measurement range on muscle stiffness estimation. Its feasibility was verified on self-made silicone phantoms by comparing with the mechanical indentation method. The system was then used to assess the stiffness of vastus intermedius (VI), one of the knee extensors, on 10 healthy elderly female subjects (56.7±4.9 yr) and 10 healthy young female subjects (27.6±5.0 yr). The VI stiffness in its action direction was confirmed to be positively correlated to the % MVC level (R2 = 0.999) over the entire range of isometric contraction, i.e. from 0% MVC (relaxed state) to 100% MVC. Furthermore, it was shown that there was no significant difference between the mean VI shear modulus of the elderly and young subjects in a relaxed state (p>0.1). However, when performing step isometric contraction, the VI stiffness of young female subjects was found to be larger than that of elderly participants (p<0.001), especially at the relatively higher contraction levels. The results expanded our knowledge on the mechanical property of the elderly’s skeletal muscle and its relationship with intensity of active contraction. Furthermore, the vibro-ultrasound system has a potential to become a powerful tool for investigating the elderly’s muscle diseases.
PMCID: PMC4081795  PMID: 24991890
2.  Exploring the Patterns of Acupuncture on Mild Cognitive Impairment Patients Using Regional Homogeneity 
PLoS ONE  2014;9(6):e99335.
To investigate the different responses to acupuncture in MCI patients and age-matched healthy subjects reflected by the Regional Homogeneity (ReHo) indices.
The experiment was performed at the acupoint KI3 in 12 MCI patients and 12 healthy controls, respectively. A novel non-repeated event-related (NRER) fMRI design paradigm was applied to separately detect neural activities related to different stages of acupuncture (pre-acupuncture resting state, needling manipulation and post-acupuncture resting state). ReHo values were calculated for MCI patients and healthy controls in pre- and post-acupuncture resting state. Then, a two-way ANCOVA with repeated measures with post-hoc two sample t-tests was performed to explore the different responses to acupuncture in the two groups.
The ANCOVA revealed a significant main effect of group, but no significant main effect of acupuncture and interactions between group and acupuncture. During the pre-acupuncture resting state, ReHo values increased in the precentral gyrus (PCG), superior frontal gyrus (SFG), and insula (INS) and decreased mainly in middle temporal gyrus (MTG), parahippocampal (PHIP) and cingulate cortex in MCI patients compared with healthy controls. Furthermore, we found that the regions including precuneus (PCUN), and cingulate cortex showed increased ReHo values for MCI patients following acupuncture. For healthy controls, the medial frontal gyrus, PCG, anterior cingulate cortex (ACC) and INS showed enhanced ReHo values following acupuncture. During the post-acupuncture resting state, MCI patients showed increased ReHo values mainly in the MTG, superior parietal lobule (SPL), middle frontal gyrus (MFG), supramarginal (SMG), and PCG, and decreased ReHo values mainly in the frontal regions, PHIP, and posterior cingulated cortex (PCC) compared to healthy controls.
Though we found some ReHo changes between MCI patients and healthy controls, the two-way ANCOVA results showed no significant effects after multiple corrections. Further study is needed to reveal the real acupuncture effects on MCI patients.
PMCID: PMC4072601  PMID: 24968124
3.  Altered functional brain networks in Prader–Willi syndrome 
NMR in biomedicine  2013;26(6):10.1002/nbm.2900.
Prader–Willi syndrome (PWS) is a genetic imprinting disorder characterized mainly by hyperphagia and early childhood obesity. Previous functional neuroimaging studies used visual stimuli to examine abnormal activities in the eating-related neural circuitry of patients with PWS. It was found that patients with PWS exhibited both excessive hunger and hyperphagia consistently, even in situations without any food stimulation. In the present study, we employed resting-state functional MRI techniques to investigate abnormal brain networks related to eating disorders in children with PWS. First, we applied amplitude of low-frequency fluctuation analysis to define the regions of interest that showed significant alterations in resting-state brain activity levels in patients compared with their sibling control group. We then applied a functional connectivity (FC) analysis to these regions of interest in order to characterize interactions among the brain regions. Our results demonstrated that patients with PWS showed decreased FC strength in the medial prefrontal cortex (MPFC)/inferior parietal lobe (IPL), MPFC/precuneus, IPL/precuneus and IPL/hippocampus in the default mode network; decreased FC strength in the pre-/postcentral gyri and dorsolateral prefrontal cortex (DLPFC)/orbitofrontal cortex (OFC) in the motor sensory network and prefrontal cortex network, respectively; and increased FC strength in the anterior cingulate cortex/insula, ventrolateral prefrontal cortex (VLPFC)/OFC and DLPFC/VLPFC in the core network and prefrontal cortex network, respectively. These findings indicate that there are FC alterations among the brain regions implicated in eating as well as rewarding, even during the resting state, which may provide further evidence supporting the use of PWS as a model to study obesity and to provide information on potential neural targets for the medical treatment of overeating.
PMCID: PMC3776442  PMID: 23335390
Prader; Willi syndrome; eating disorder; obesity; amplitude of low-frequency fluctuation; resting-state networks; functional MRI
4.  Incorporating MRI structural information into bioluminescence tomography: system, heterogeneous reconstruction and in vivo quantification 
Biomedical Optics Express  2014;5(6):1861-1876.
Combining two or more imaging modalities to provide complementary information has become commonplace in clinical practice and in preclinical and basic biomedical research. By incorporating the structural information provided by computed tomography (CT) or magnetic resonance imaging (MRI), the ill poseness nature of bioluminescence tomography (BLT) can be reduced significantly, thus improve the accuracies of reconstruction and in vivo quantification. In this paper, we present a small animal imaging system combining multi-view and multi-spectral BLT with MRI. The independent MRI-compatible optical device is placed at the end of the clinical MRI scanner. The small animal is transferred between the light tight chamber of the optical device and the animal coil of MRI via a guide rail during the experiment. After the optical imaging and MRI scanning procedures are finished, the optical images are mapped onto the MRI surface by interactive registration between boundary of optical images and silhouette of MRI. Then, incorporating the MRI structural information, a heterogeneous reconstruction algorithm based on finite element method (FEM) with L 1 normalization is used to reconstruct the position, power and region of the light source. In order to validate the feasibility of the system, we conducted experiments of nude mice model implanted with artificial light source and quantitative analysis of tumor inoculation model with MDA-231-GFP-luc. Preliminary results suggest the feasibility and effectiveness of the prototype system.
PMCID: PMC4052915  PMID: 24940545
(110.0110) Imaging systems; (170.3880) Medical and biological imaging; (110.6955) Tomographic imaging
5.  Adipose Tissue Dendritic Cells Enhances Inflammation by Prompting the Generation of Th17 Cells 
PLoS ONE  2014;9(3):e92450.
Obesity has become a global challenge for public health. It has been reported that obesity is associated with chronic inflammation. However, the mechanism for the chronic inflammation contributes to obesity remains elusive.
Methodology/Principal Findings
In our study, we found a novel CD11c+ dendritic cell subset existed in murine adipose tissues which was immature phenotype. Moreover, as compared to the lean controls, the number of CD11c+ DCs and CD4+IL-17+T cells were higher in adipose tissue of high fat diet (HFD) mice. Adipose tissues derived dendritic cells (ATDCs) displayed lower levels of CD40, CD80, CD86, MHCI and MHCII expression than splenic DCs (SPDCs). However, ATDCs showed higher levels of IL-6, TGF-β and IL-23 secretion. Moreover, our in vitro experiments demonstrated that ATDCs were capable of promoting Th17 cell generation.
Our results indicate the existence of CD11c+ DCs in adipose tissues, which displays an immature phenotype but possessing pro-inflammatory function.
PMCID: PMC3958510  PMID: 24642966
6.  Islet-1 promotes the cardiac-specific differentiation of mesenchymal stem cells through the regulation of histone acetylation 
The aim of the present study was to investigate the effects of Islet-1 on the process of mesenchymal stem cell (MSC) differentiation into cardiomyocyte-like cells and to elucidate the possible mechanisms involved. Lentiviral vectors expressing Islet-1 (Lenti-Islet-1) were constructed and used for C3H10T1/2 cell transfection. Cell morphology was observed. Cardiac-related genes and proteins were detected by qPCR and western blot analysis. Epigallocatechin gallate (EGCG) was used as an inhibitor of acetylated histone H3 (AcH3). AcH3 was detected by chromatin immunoprecipitation. Cells overexpressing Islet-1 tended to change into fibroblast-like cells and were arranged in the same direction. The enhanced expression of GATA binding protein 4 (Gata4), NK2 homeobox 5 (Nkx2.5), myocyte enhancer factor 2C (Mef2c) and cardiac troponin T (cTnT) was observed in the cells overexpressing Islet-1 following transfection with Lenti-Islet-1. However, the expression of hepatocyte-, bone- and neuronal-specific markers was not affected by Islet-1. The AcH3 relative amount increased following transfection with Lenti-Islet-1, which was associated with the enhanced expression of Gata4, Nkx2.5 and Mef2c in these cells. The expression of Gata4, Nkx2.5 and Mef2c in the C3H10T1/2 cells transfected with Lenti-Islet-1 and treated with EGCG was reduced following treatment with EGCG. The data presented in this study indicate that Islet-1 specifically induces the differentiation of C3H10T1/2 cells into cardiomyocyte-like cells, and one of the mechanisms involved is the regulation of histone acetylation.
PMCID: PMC4020474  PMID: 24604334
mesenchymal stem cells; cardiomyocyte; differentiation; histone acetylation
7.  Automated Delineation of Lung Tumors from CT Images Using a Single Click Ensemble Segmentation Approach 
Pattern recognition  2013;46(3):692-702.
A single click ensemble segmentation (SCES) approach based on an existing “Click&Grow” algorithm is presented. The SCES approach requires only one operator selected seed point as compared with multiple operator inputs, which are typically needed. This facilitates processing large numbers of cases. Evaluation on a set of 129 CT lung tumor images using a similarity index (SI) was done. The average SI is above 93% using 20 different start seeds, showing stability. The average SI for 2 different readers was 79.53%. We then compared the SCES algorithm with the two readers, the level set algorithm and the skeleton graph cut algorithm obtaining an average SI of 78.29%, 77.72%, 63.77% and 63.76% respectively. We can conclude that the newly developed automatic lung lesion segmentation algorithm is stable, accurate and automated.
PMCID: PMC3580869  PMID: 23459617
Image Features; Delineation; Lung Tumor; Lesion; CT; Region growing; Ensemble Segmentation
8.  Estimates of Forest Biomass Carbon Storage in Liaoning Province of Northeast China: A Review and Assessment 
PLoS ONE  2014;9(2):e89572.
Accurate estimates of forest carbon storage and changes in storage capacity are critical for scientific assessment of the effects of forest management on the role of forests as carbon sinks. Up to now, several studies reported forest biomass carbon (FBC) in Liaoning Province based on data from China's Continuous Forest Inventory, however, their accuracy were still not known. This study compared estimates of FBC in Liaoning Province derived from different methods. We found substantial variation in estimates of FBC storage for young and middle-age forests. For provincial forests with high proportions in these age classes, the continuous biomass expansion factor method (CBM) by forest type with age class is more accurate and therefore more appropriate for estimating forest biomass. Based on the above approach designed for this study, forests in Liaoning Province were found to be a carbon sink, with carbon stocks increasing from 63.0 TgC in 1980 to 120.9 TgC in 2010, reflecting an annual increase of 1.9 TgC. The average carbon density of forest biomass in the province has increased from 26.2 Mg ha−1 in 1980 to 31.0 Mg ha−1 in 2010. While the largest FBC occurred in middle-age forests, the average carbon density decreased in this age class during these three decades. The increase in forest carbon density resulted primarily from the increased area and carbon storage of mature forests. The relatively long age interval in each age class for slow-growing forest types increased the uncertainty of FBC estimates by CBM-forest type with age class, and further studies should devote more attention to the time span of age classes in establishing biomass expansion factors for use in CBM calculations.
PMCID: PMC3934887  PMID: 24586881
9.  CITED2 Mutation and methylation in children with congenital heart disease 
The occurrence of Congenital Heart Disease (CHD) is resulted from either genetic or environmental factors or the both. The CITED2 gene deletion or mutation is associated with the development of cardiac malformations. In this study, we have investigated the role of CITED2 gene mutation and methylation in the development of Congenital Heart Disease in pediatric patients in China.
We have screened 120 pediatric patients with congenital heart disease. Among these patients, 4 cases were detected to carry various CITED2 gene heterozygous mutations (c.550G > A, c.574A > G, c.573-578del6) leading correspondingly to the alterations of amino acid sequences in Gly184Ser, Ser192Gly, and Ser192fs, respectively. No CITED2 gene mutations were detected in the control group. At the same time, we found that CITED2 mutations could inhibit TFAP2c expression. In addition, we have demonstrated that abnormal CITED2 gene methylation was detected in most of the tested pediatric patients with CHD, which leads to a decrease of CITED2 transcription activities.
Our study suggests that CITED2 gene mutations and methylation may play an important role in the development of pediatric congenital heart disease.
PMCID: PMC3917535  PMID: 24456003
CITED2; Mutation; Methylation; Congenital heart disease
10.  Comprehensive Evaluation of the Anti-Angiogenic and Anti-Neoplastic Effects of Endostar on Liver Cancer through Optical Molecular Imaging 
PLoS ONE  2014;9(1):e85559.
Molecular imaging enables non-invasive monitoring of tumor growth, progression, and drug treatment response, and it has become an important tool to promote biological studies in recent years. In this study, we comprehensively evaluated the in vivo anti-angiogenic and anti-neoplastic effects of Endostar on liver cancer based on the optical molecular imaging systems including micro-computer tomography (Micro-CT), bioluminescence molecular imaging (BLI) and fluorescence molecular tomography (FMT). Firefly luciferase (fLuc) and green fluorescent protein (GFP) dual labeled human hepatocellular carcinoma cells (HCC-LM3-fLuc-GFP cells) were used to establish the subcutaneous and orthotopic liver tumor model. After the tumor cells were implanted 14∼18 days, Endostar (5 mg/kg/day) was administered through an intravenous tail vein injection for continuous 14 days. The computer tomography angiography (CTA) and BLI were carried out for the subcutaneous tumor model. FMT was executed for the orthotopic tumor model. The CTA data showed that tumor vessel formation and the peritumoral vasculature of subcutaneous tumor in the Endostar treatment group was significantly inhibited compared to the control group. The BLI data exhibited the obvious tumor inhibition day 8 post-treatment. The FMT detected the tumor suppression effects of Endostar as early as day 4 post-treatment and measured the tumor location. The above data confirmed the effects of Endostar on anti-angiogenesis and tumor suppression on liver cancer. Our system combined CTA, BLI, and FMT to offer more comprehensive information about the effects of Endostar on the suppression of vessel and tumor formation. Optical molecular imaging system enabled the non-invasive and reliable assessment of anti-tumor drug efficacy on liver cancer.
PMCID: PMC3885728  PMID: 24416426
11.  Fast and robust reconstruction for fluorescence molecular tomography via a sparsity adaptive subspace pursuit method 
Biomedical Optics Express  2014;5(2):387-406.
Fluorescence molecular tomography (FMT), as a promising imaging modality, can three-dimensionally locate the specific tumor position in small animals. However, it remains challenging for effective and robust reconstruction of fluorescent probe distribution in animals. In this paper, we present a novel method based on sparsity adaptive subspace pursuit (SASP) for FMT reconstruction. Some innovative strategies including subspace projection, the bottom-up sparsity adaptive approach, and backtracking technique are associated with the SASP method, which guarantees the accuracy, efficiency, and robustness for FMT reconstruction. Three numerical experiments based on a mouse-mimicking heterogeneous phantom have been performed to validate the feasibility of the SASP method. The results show that the proposed SASP method can achieve satisfactory source localization with a bias less than 1mm; the efficiency of the method is much faster than mainstream reconstruction methods; and this approach is robust even under quite ill-posed condition. Furthermore, we have applied this method to an in vivo mouse model, and the results demonstrate the feasibility of the practical FMT application with the SASP method.
PMCID: PMC3920871  PMID: 24575335
(100.3010) Image reconstruction techniques; (100.3190) Inverse problems; (110.6955) Tomographic imaging; (170.3660) Light propagation in tissues; (170.3880) Medical and biological imaging; (290.1990) Diffusion; (290.7050) Turbid media
12.  Influence of Acupuncture Stimulation on Cerebral Network in Functional Diarrhea 
Acupuncture is a commonly used therapy for treating functional diarrhea (FD), although there is limited knowledge on the mechanism. The objectives of this study were to investigate the differences in brain activities elicited by acupuncture between FD patients and healthy controls (HC) so as to explore the possible mechanism. Eighteen FD patients and eighteen HC received 10 sessions of acupuncture treatment at ST25 acupoints. Functional magnetic resonance imaging (fMRI) scans were, respectively, performed before and after acupuncture. The defecation frequency, Bristol stool form scale (SBFS), and MOS 36-item Short Healthy Survey (SF-36) were employed to evaluate the clinical efficacy. After acupuncture, the FD patients showed a significant decrease in defecation frequency and BSFS score. The regional homogeneity (ReHo) map showed a decrease in the paracentral lobule and postcentral gyrus, and an increase in the angular gyrus, insula, anterior cingulate cortex (ACC), and precuneus in the FD group. Moreover, the changes in ReHo values in the ACC were correlated with the reduction in defecation frequency. Decreasing functional connectivity among the ACC, insula, thalamus, and orbital frontal cortex only existed in the FD group. Conclusively, acupuncture alleviated defecation frequency and improved stool formation in FD patients. The efficacy might result from the regulation of the homeostasis afferent processing network.
PMCID: PMC3888684  PMID: 24459533
13.  Use of Indocyanine Green for Detecting the Sentinel Lymph Node in Breast Cancer Patients: From Preclinical Evaluation to Clinical Validation 
PLoS ONE  2013;8(12):e83927.
Assessment of the sentinel lymph node (SLN) in patients with early stage breast cancer is vital in selecting the appropriate surgical approach. However, the existing methods, including methylene blue and nuclides, possess low efficiency and effectiveness in mapping SLNs, and to a certain extent exert side effects during application. Indocyanine green (ICG), as a fluorescent dye, has been proved reliable usage in SLN detection by several other groups. In this paper, we introduce a novel surgical navigation system to detect SLN with ICG. This system contains two charge-coupled devices (CCD) to simultaneously capture real-time color and fluorescent video images through two different bands. During surgery, surgeons only need to follow the fluorescence display. In addition, the system saves data automatically during surgery enabling surgeons to find the registration point easily according to image recognition algorithms. To test our system, 5 mice and 10 rabbits were used for the preclinical setting and 22 breast cancer patients were utilized for the clinical evaluation in our experiments. The detection rate was 100% and an average of 2.7 SLNs was found in 22 patients. Our results show that the usage of our surgical navigation system with ICG to detect SLNs in breast cancer patients is technically feasible.
PMCID: PMC3865279  PMID: 24358319
14.  Transgenic Insulin-like Growth Factor-1 stimulates activation of COX-2 signaling in mammary glands 
Molecular carcinogenesis  2011;51(12):973-983.
Studies show that elevated IGF-1 levels are associated with an increased risk of breast cancer; however, mechanisms through which IGF-1 promotes mammary tumorigenesis in vivo have not been fully elucidated. To assess the possible involvement of COX-2 signaling in the protumorigenic effects of IGF-1 in mammary glands, we used the unique BK5.IGF-1 mouse model in which transgenic (Tg) mice have significantly increased incidence of spontaneous and DMBA–induced mammary cancer compared to wild type (WT) littermates. Studies revealed that COX-2 expression was significantly increased in Tg mammary glands and tumors, compared to age-matched WTs. Consistent with this, PGE2 levels were also increased in Tg mammary glands. Analysis of expression of the EP receptors that mediate the effects of PGE2 showed that among the four G-protein-coupled receptors, EP3 expression was elevated in Tg glands. Up-regulation of the COX-2/PGE2/EP3 pathway was accompanied by increased expression of VEGF and a striking enhancement of angiogenesis in IGF-1 Tg mammary glands. Treatment with celecoxib, a selective COX-2 inhibitor, caused a 45% reduction in mammary PGE2 levels, attenuated the influx of mast cells and reduced vascularization in Tg glands. These findings indicate that the COX-2/PGE2/EP3 signaling pathway is involved in IGF-1–stimulated mammary tumorigenesis and that COX-2–selective inhibitors may be useful in the prevention or treatment of breast cancer associated with elevated IGF-1 levels in humans.
PMCID: PMC3790642  PMID: 22006370
mammary cancer; IGF-1; COX-2; stroma; transgenic mouse
15.  A dynamic causal modeling analysis of the effective connectivities underlying top-down letter processing 
Neuropsychologia  2011;49(5):10.1016/j.neuropsychologia.2011.01.011.
The present study employed Dynamic Causal Modeling to investigate the effective functional connectivity between regions of the neural network involved in top-down letter processing. We used an illusory letter detection paradigm in which participants detected letters while viewing pure noise images. When participants detected letters, the response of the right middle occipital gyrus (MOG) in the visual cortex was enhanced by increased feed-backward connectivity from the left inferior frontal gyrus (IFG). In addition, illusory letter detection increased feed-forward connectivity from the right MOG to the left inferior parietal lobules. Originating in the left IFG, this top-down letter processing network may facilitate the detection of letters by activating letter processing areas within the visual cortex. This activation in turns may highlight the visual features of letters and send letter information to activate the associated phonological representations in the identified parietal region.
PMCID: PMC3817006  PMID: 21237182
letter processing; word processing; top-down processing; fMRI; dynamic causal modeling
16.  Amplitude of Low Frequency Fluctuation Abnormalities in Adolescents with Online Gaming Addiction 
PLoS ONE  2013;8(11):e78708.
The majority of previous neuroimaging studies have demonstrated both structural and task-related functional abnormalities in adolescents with online gaming addiction (OGA). However, few functional magnetic resonance imaging (fMRI) studies focused on the regional intensity of spontaneous fluctuations in blood oxygen level-dependent (BOLD) during the resting state and fewer studies investigated the relationship between the abnormal resting-state properties and the impaired cognitive control ability. In the present study, we employed the amplitude of low frequency fluctuation (ALFF) method to explore the local features of spontaneous brain activity in adolescents with OGA and healthy controls during resting-state. Eighteen adolescents with OGA and 18 age-, education- and gender-matched healthy volunteers participated in this study. Compared with healthy controls, adolescents with OGA showed a significant increase in ALFF values in the left medial orbitofrontal cortex (OFC), the left precuneus, the left supplementary motor area (SMA), the right parahippocampal gyrus (PHG) and the bilateral middle cingulate cortex (MCC). The abnormalities of these regions were also detected in previous addiction studies. More importantly, we found that ALFF values of the left medial OFC and left precuneus were positively correlated with the duration of OGA in adolescents with OGA. The ALFF values of the left medial OFC were also correlated with the color-word Stroop test performance. Our results suggested that the abnormal spontaneous neuronal activity of these regions may be implicated in the underlying pathophysiology of OGA.
PMCID: PMC3817073  PMID: 24223843
17.  Correlation between the Frequency of Th17 Cell and the Expression of MicroRNA-206 in Patients with Dermatomyositis 
It was reported that IL-17 had been detected in the inflammatory infiltrates of patients with DM (dermatomyositis). In this study, we investigated the frequency of Th17 cells and the expression of microRNA-206 (miR-206) in DM patients. Firstly, we observed that the frequency of Th17 cells and the expression of transcription factors were increased significantly in the PBMCs of DM patients. Secondly, we found that there was a positive correlation between the percentages of Th17 cells and serum level of CK in DM patients. And the serum concentrations of IL-6, IL-1β, TGF-β, and IL-23, the important cytokines of Th17 differentiation, were increased in DM patients. It was predicted that Krüppel-like factor 4 (KLF4) is one of the multiple targets of miR-206. We detected the expression of miR-206 in DM patients, and it was decreased in the serum and PBMCs of DM patients. The augmented expression of KLF is accompanied by the attenuated expression of miR-206. Furthermore, a negative correlation between the percentages of Th17 cells and the expression of miR-206 in DM patients has been found. Taken together, these findings suggest the attenuated expression of miR-206, and the augmented frequency of Th17 cells in DM patients.
PMCID: PMC3830811  PMID: 24288551
18.  Islet-1 May Function as an Assistant Factor for Histone Acetylation and Regulation of Cardiac Development-Related Transcription Factor Mef2c Expression  
PLoS ONE  2013;8(10):e77690.
Islet-1 is an important transcription factor for cardiac development through mediating extensive interactions between DNA and proteins. The present study was to investigate the role of Islet-1 in regulating the expression of cardiac development-related transcription factors and mechanism.
Methods and Results
The expression of Islet-1 and histone acetylases (HATs) subtype p300 was determined in newborn mouse hearts and mouse embryonic hearts at different development stages using Western blot. The expression of Islet-1 and cardiac development-related transcription factors Mef2c, GATA4 and Tbx5 as well as histone H3 acetylation level were determined in cardiac progenitor cells with and without transfection of Islet-1 interference RNA (RNAi) in lentivirus using PCR and Western blot. Islet-1 peak expression occurred on day E14.5 in mouse embryonic heart, and was present in the promoter regions of Mef2c, GATA4 and Tbx5 that were precipitated with p300 antibody. When Islet-1 was inhibited with specific RNAi in cardiac progenitor cells, the expression of Mef2c and Tbx5, but not GATA4, was significantly suppressed along with selective reduction in histone H3 acetylation in the promoter region of Mef2c, but not GATA4 and Tbx5. The level of Mef2c DNA, not GATA4 and Tbx5, in the complex associated with p300 was significantly decreased in the cells with Islet-1 knockdown.
These data suggested that Islet-1 might function as an assistant factor that was involved in the regulation of histone acetylation and Mef2c expression via assisting p300 on specifically targeting the promoter of Mef2c.
PMCID: PMC3798409  PMID: 24147056
19.  Effective connectivities of cortical regions for top-down face processing: A Dynamic Causal Modeling study 
Brain research  2010;1340:40-51.
To study top-down face processing, the present study used an experimental paradigm in which participants detected non-existent faces in pure noise images. Conventional BOLD signal analysis identified three regions involved in this illusory face detection. These regions included the left orbitofrontal cortex (OFC) in addition to the right fusiform face area (FFA) and right occipital face area (OFA), both of which were previously known to be involved in both top-down and bottom-up processing of faces. We used Dynamic Causal Modeling (DCM) and Bayesian model selection to further analyze the data, revealing both intrinsic and modulatory effective connectivities among these three cortical regions. Specifically, our results support the claim that the orbitofrontal cortex plays a crucial role in the top-down processing of faces by regulating the activities of the occipital face area, and the occipital face area in turn detects the illusory face features in the visual stimuli and then provides this information to the fusiform face area for further analysis.
PMCID: PMC3724518  PMID: 20423709
Face processing; Top-down processing; Bottom-up processing; Dynamic Causal Modeling (DCM); Orbitofrontal cortex (OFC)
20.  Identifying Neural Patterns of Functional Dyspepsia Using Multivariate Pattern Analysis: A Resting-State fMRI Study 
PLoS ONE  2013;8(7):e68205.
Previous imaging studies on functional dyspepsia (FD) have focused on abnormal brain functions during special tasks, while few studies concentrated on the resting-state abnormalities of FD patients, which might be potentially valuable to provide us with direct information about the neural basis of FD. The main purpose of the current study was thereby to characterize the distinct patterns of resting-state function between FD patients and healthy controls (HCs).
Methodology/Principal Findings
Thirty FD patients and thirty HCs were enrolled and experienced 5-mintue resting-state scanning. Based on the support vector machine (SVM), we applied multivariate pattern analysis (MVPA) to investigate the differences of resting-state function mapped by regional homogeneity (ReHo). A classifier was designed by using the principal component analysis and the linear SVM. Permutation test was then employed to identify the significant contribution to the final discrimination. The results displayed that the mean classifier accuracy was 86.67%, and highly discriminative brain regions mainly included the prefrontal cortex (PFC), orbitofrontal cortex (OFC), supplementary motor area (SMA), temporal pole (TP), insula, anterior/middle cingulate cortex (ACC/MCC), thalamus, hippocampus (HIPP)/parahippocamus (ParaHIPP) and cerebellum. Correlation analysis revealed significant correlations between ReHo values in certain regions of interest (ROI) and the FD symptom severity and/or duration, including the positive correlations between the dmPFC, pACC and the symptom severity; whereas, the positive correlations between the MCC, OFC, insula, TP and FD duration.
These findings indicated that significantly distinct patterns existed between FD patients and HCs during the resting-state, which could expand our understanding of the neural basis of FD. Meanwhile, our results possibly showed potential feasibility of functional magnetic resonance imaging diagnostic assay for FD.
PMCID: PMC3709912  PMID: 23874543
21.  Regional Brain Structural Abnormality in Meal-Related Functional Dyspepsia Patients: A Voxel-Based Morphometry Study 
PLoS ONE  2013;8(7):e68383.
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.
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.
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.
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.
PMCID: PMC3699561  PMID: 23844192
22.  Manipulation of and Sustained Effects on the Human Brain Induced by Different Modalities of Acupuncture: An fMRI Study 
PLoS ONE  2013;8(6):e66815.
The javascript:void(0)manipulation and sustained effects of acupuncture have been investigated in multiple studies, but several findings are inconsistent with one another. One possible explanation for these discrepancies is that different modalities of acupuncture were utilized in these studies. In the present study, we investigated both the manipulation and sustained effects of acupuncture in different modalities, including manual acupuncture (MA), electroacupuncture (EA) and transcutaneous electrical acupoint stimulation (TEAS). MA, EA, TEAS and sensory control stimulation were applied to 18 healthy subjects, and combined block-designed and resting-state fMRI scans were performed. In analyzing these data, the block-designed datasets were used to assess the manipulation effect by employing a modified general linear model. The data from the resting states, before and after stimulation, were used to explore the brain networks involved in the sustained effect. The results showed that the two 1-min stimulation periods produced similar activation patterns in the sensory control with positive activation in the sensorimotor areas and negative activation in the default mode areas. Although similar patterns could be detected in the first stimulation period in MA, EA and TEAS, no positive activation result was observed in the second stimulation period, and EA showed a more extensive deactivation compared to MA and TEAS. Additionally, all three of the modalities of acupuncture stimulation could increase the instinct brain network in rest. A more secure and spatially extended connectivity of the default mode network was observed following MA and EA, and TEAS specifically increased the functional connectivity in the sensorimotor network. The present study suggested that different brain mechanisms might be recruited in different acupuncture modalities. In addition, the findings from our work could provide methodological information for further research into the mechanism of acupuncture.
PMCID: PMC3696086  PMID: 23840533
23.  Length of Acupuncture Training and Structural Plastic Brain Changes in Professional Acupuncturists 
PLoS ONE  2013;8(6):e66591.
The research on brain plasticity has fascinated researchers for decades. Use/training serves as an instrumental factor to influence brain neuroplasticity. Parallel to acquisition of behavioral expertise, extensive use/training is concomitant with substantial changes of cortical structure. Acupuncturists, serving as a model par excellence to study tactile-motor and emotional regulation plasticity, receive intensive training in national medical schools following standardized training protocol. Moreover, their behavioral expertise is corroborated during long-term clinical practice. Although our previous study reported functional plastic brain changes in the acupuncturists, whether or not structural plastic changes occurred in acupuncturists is yet elusive.
Methodology/Principal Findings
Cohorts of acupuncturists (N = 22) and non-acupuncturists (N = 22) were recruited. Behavioral tests were delivered to assess the acupuncturists’ behavioral expertise. The results confirmed acupuncturists’ tactile-motor skills and emotion regulation proficiency compared to non-acupuncturists. Using the voxel-based morphometry technique, we revealed larger grey matter volumes in acupuncturists in the hand representation of the contralateral primary somatosensory cortex (SI), the right lobule V/VI and the bilateral ventral anterior cingulate cortex/ventral medial prefrontal cortex. Grey matter volumes of the SI and Lobule V/VI positively correlated with the duration of acupuncture practice.
To our best knowledge, this study provides first evidence for the anatomical alterations in acupuncturists, which would possibly be the neural correlates underlying acupuncturists’ exceptional skills. On one hand, we suggest our findings may have ramifications for tactile-motor rehabilitation. On the other hand, our results in emotion regulation domain may serve as a target for our future studies, from which we can understand how modulations of aversive emotions elicited by empathic pain develop in the context of expertise. Future longitudinal study is necessary to establish the presence and direction of a causal link between practice/use and brain anatomy.
PMCID: PMC3686711  PMID: 23840505
24.  Whole-Brain Functional Connectivity Identification of Functional Dyspepsia 
PLoS ONE  2013;8(6):e65870.
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.
PMCID: PMC3684590  PMID: 23799056
25.  Identification of Cancer Stem-Like Side Population Cells in Purified Primary Cultured Human Laryngeal Squamous Cell Carcinoma Epithelia 
PLoS ONE  2013;8(6):e65750.
Cancer stem-like side population (SP) cells have been identified in many solid tumors; however, most of these investigations are performed using established cancer cell lines. Cancer cells in tumor tissue containing fibroblasts and many other types of cells are much more complex than any cancer cell line. Although SP cells were identified in the laryngeal squamous cell carcinoma (LSCC) cell line Hep-2 in our pilot study, it is unknown whether the LSCC tissue contains SP cells. In this study, LSCC cells (LSCCs) were primary cultured and purified from a surgically resected LSCC specimen derived from a well-differentiated epiglottic neoplasm of a Chinese male. This was followed by the verification of epithelium-specific characteristics, such as ultrastructure and biomarkers. A distinct SP subpopulation (4.45±1.07%) was isolated by Hoechst 33342 efflux analysis from cultured LSCCs by using a flow cytometer. Cancer stem cell (CSC)-associated assays, including expression of self-renewal and CSC marker genes, proliferation, differentiation, spheroid formation, chemotherapy resistance, and tumorigenicity were then conducted between SP and non-SP (NSP) LSCCs. In vitro and in vivo assays revealed that SP cells manifested preferential expression of self-renewal and CSC marker genes, higher capacity for proliferation, differentiation, and spheroid formation; enhanced resistance to chemotherapy; and greater xenograft tumorigenicity in immunodeficient mice compared with NSP cells. These findings suggest that the primary cultured and purified LSCCs contain cancer stem-like SP cells, which may serve as a valuable model for CSC research in LSCC.
PMCID: PMC3679141  PMID: 23776540

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