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author:("Wang, hailing")
1.  Molecular characterization and phylogenetic analysis of dengue virus type 1 in Guangdong in 2014 
SpringerPlus  2016;5(1):1942.
Dengue is one of the most important emerging diseases of humans, with no preventive vaccines or antiviral cures available currently. In 2014, the Southeast Asian region experienced an unprecedented outbreak of dengue, especially in Guangdong, China.
The nucleotide sequences of the E gene from 23 patients sera of dengue virus type 1 (DENV-1) from Guangzhou, China, were determined. One isolate that was recovered from a patient with serious liver damage was designated GZ02. The whole genome sequence of GZ02 was amplified, and confocal microscopy and plaque reduction neutralization test were performed to investigate the replication kinetics in liver L02 cells. In the study, assembly and genetic comparisons showed 11 of those E gene nucleotide sequences were absolutely accordant, and the nucleic acid sequence divergence among the other strains had no marked difference.
Phylogenetic analysis based on the E gene indicated that the 23 new strains were closely related to strains from Malaysia or Singapore. Two different genotypes (genotype I and III) of DENV-1 were co-circulating in Guangdong, Malaysia, and Singapore from 2013 to 2014. However, no recombination event was found after 2005 between DENV strains from Guangdong and Malaysia or Singapore. GZ02 had a significant replicative advantage over DG14 and the DV1 standard strain. Importation of DENV-1 from Southeast Asian countries may have been an important contributing factor to the 2014 outbreak in Guangdong.
PMCID: PMC5102991  PMID: 27933232
Dengue virus type 1; E gene; Phylogenetic analysis; Virus isolation
2.  Hypothalamic gastrin-releasing peptide receptor mediates an antidepressant-like effect in a mouse model of stress 
Evidence has shown that gastrin-releasing peptide receptor (GRPR) is involved in responses to stress and anxiety. The primary role of GRPR is to stimulate corticotrophin-releasing hormone (CRH) or adrenocorticotropic hormone (ACTH) secretion. Thus, the mechanisms of GRPR signaling should be elucidated to discover novel therapeutic targets for treating depression. This study aimed to investigate GRPR alterations in the C57 mouse hypothalamus after the animals were subjected to stress and fluoxetine treatments. Specifically, we subjected the mice to isolation and chronic unpredictable mild stress (CUMS) for three weeks to establish an experimental model of depression. These mice were subsequently treated with fluoxetine for three weeks. Then, we performed the sucrose preference test and the open field test and measured food intake and body weight to explore the effects of stress and fluoxetine on activity and anhedonia. After fluoxetine treatment, we also assessed changes in the levels of GRPR expression in the hypothalamus using immunohistochemistry, western blotting, and real-time quantitative PCR (RT-PCR). We found that stressed mice showed significant reductions in locomotion, food intake/body weight, and sucrose preference; these reduced parameters indicated a state of anhedonia. Marked increases in mRNA and protein expression of GRPR in the hypothalamus of CUMS-exposed mice were also observed, although treatment with fluoxetine reversed these stress-induced changes. Our results also demonstrated the feasibility and effectiveness of the C57 mouse model of depression established by CUMS and isolation. After fluoxetine treatment was administered, the animals’ depression symptoms were alleviated, and these behavioral alterations were accompanied by specific changes in mRNA and protein expression of GRPR in the hypothalamus. These results suggest that GRPR may be implicated in depression; therefore, new therapeutic targets of depression focused on GRPR signaling should be explored.
PMCID: PMC4969446  PMID: 27508030
Depression; GRPR; hypothalamus; antidepressant
3.  Single rodent mesohabenular axons release glutamate and GABA 
Nature neuroscience  2014;17(11):1543-1551.
The lateral habenula (LHb) is involved in reward, aversion, addiction, and depression, through descending interactions with several brain structures, including the ventral tegmental area (VTA). VTA provides reciprocal inputs to LHb, but their actions are unclear. Here we show that the majority of rat and mouse VTA neurons innervating LHb co-express markers for both glutamate-signaling (vesicular glutamate transporter 2, VGluT2) and GABA-signaling (glutamate decarboxylase, GAD; and vesicular GABA transporter, VGaT). A single axon from these mesohabenular neurons co-expresses VGluT2-protein and VGaT-protein, and surprisingly establishes symmetric and asymmetric synapses on LHb neurons. In LHb slices, light activation of mesohabenular fibers expressing channelrhodopsin-2 (ChR2) driven by VGluT2 or VGaT promoters elicits release of both glutamate and GABA onto single LHb neurons. In vivo light-activation of mesohabenular terminals inhibits or excites LHb neurons. Our findings reveal an unanticipated type of VTA neuron that co-transmits glutamate and GABA, and provides the majority of mesohabenular inputs.
PMCID: PMC4843828  PMID: 25242304
dopamine; reward; aversion; addiction; VGluT2; GAD; cotransmission; corelease
4.  Pro-inflammatory miR-223 mediates the cross-talk between the IL23 pathway and the intestinal barrier in inflammatory bowel disease 
Genome Biology  2016;17:58.
The IL23/Th17 pathway is essential for the onset of inflammatory bowel disease (IBD), yet the specific mechanism by which this pathway initiates the disease remains unknown. In this study, we identify the mechanisms that mediate cross-talk between the IL23 pathway and the intestinal barrier in IBD.
The downstream targets of the IL23 pathway were identified by RNA array profiling and confirmed by immunohistochemical staining. The role of miRNAs that interact with IL23 was explored in mice with TNBS-induced colitis. Claudin-8 (CLDN8), a multigene family protein that constitutes the backbone of tight junctions, was identified as a novel target of IL23 in IBD. CLDN8 was significantly downregulated in IBD patients with inflamed colonic mucosa, and in trinitrobenzene sulphonic acid (TNBS) induced colitis in mice. Therapeutic treatment of colitis in mice using an IL23 antibody restored CLDN8 abundance, in parallel with recovery from colitis. In addition, we identify miR-223 as a novel mediator of the crosstalk between the IL23 signal pathway and CLDN8 in the development of IBD. MiR-223 was upregulated in IBD, and its activity was regulated through the IL23 pathway. Antagomir inhibition of miR-223 reactivated CLDN8 and improved a number of signs associated with TNBS-induced colitis in mice.
Our study characterizes a new mechanistic pathway in IBD, in which miR-223 interacts with the IL23 pathway by targeting CLDN8. Strategies designed to disrupt this interaction may provide novel therapeutic agents for the management of IBD.
Electronic supplementary material
The online version of this article (doi:10.1186/s13059-016-0901-8) contains supplementary material, which is available to authorized users.
PMCID: PMC4815271  PMID: 27029486
Crohn’s disease; Ulcerative colitis; Interleukin 23; miRNA; Pathway
5.  Ameliorating effect of luteolin on memory impairment in an Alzheimer's disease model 
Molecular Medicine Reports  2016;13(5):4215-4220.
Alzheimer's disease (AD) is one of the most prevalent neurodegenerative disorder. It is characterized by the formation of amyloid plaques and neurofibrillary tangles in the brain, the degeneration of cholinergic neurons and neuronal cell death. The present study aimed to investigate the effect of luteolin, a flavonoid compound, on memory impairment in a streptozotocin (STZ)-induced Alzheimer's rat model. Morris water maze and probe tests were performed to examine the effect of luteolin treatment on cognition and memory. The effect of luteolin on CA1 pyramidal layer thickness was also examined. The results demonstrated that luteolin significantly ameliorated the spatial learning and memory impairment induced by STZ treatment. STZ significantly reduced the thickness of CA1 pyramidal layer and treatment of luteolin completely abolished the inhibitory effect of STZ. Our results suggest that luteolin has a potentially protective effect on learning defects and hippocampal structures in AD.
PMCID: PMC4838167  PMID: 27035793
Alzheimer's disease; Morris water maze test; luteolin
6.  Circulating MicroRNA223 is a New Biomarker for Inflammatory Bowel Disease 
Medicine  2016;95(5):e2703.
Endoscopy is an important tool in screening and monitoring inflammatory bowel disease (IBD); however, it is invasive, costly, and associated with risks to the patients. Recently, circulating microRNAs (miRNAs) have emerged as promising noninvasive biomarkers. We proposed that the expression of serum microRNA223 (miR-223) could be a biomarker for IBD.
Studies were conducted using serum samples from 100 patients with IBD (50 with Crohn's disease [CD] and 50 with ulcerative colitis [UC]) and 50 healthy controls. The expression of serum miR-223 was measured by quantitative reverse transcription-polymerase chain reaction. The clinical disease activity was assessed by measurement of the Crohn's disease activity index for CD and the Mayo score for UC. Endoscopies were performed and graded according to the simple endoscopic score for CD and the ulcerative colitis endoscopic index of severity scores for UC. Blood samples for the measurement of high-sensitivity C-reactive protein (hs-CRP) and erythrocyte sedimentation rate (ESR) were taken within 1 week before or after endoscopy.
Serum miR-223 expression increased 2.2 times in patients with CD and 2.8 times in patients with UC compared with the control group. Most importantly, the level of serum miR-223 was correlated with several indicators of disease activity both in CD and UC. Serum miR-223 demonstrated a higher Spearman r value than ESR and hs-CRP in detecting the disease activity of patients with IBD.
Serum miR-223 might be a promising biomarker for monitoring disease activity in IBD patients.
PMCID: PMC4748929  PMID: 26844512
7.  Repertaxin, an inhibitor of the chemokine receptors CXCR1 and CXCR2, inhibits malignant behavior of human gastric cancer MKN45 cells in vitro and in vivo and enhances efficacy of 5-fluorouracil 
International Journal of Oncology  2016;48(4):1341-1352.
Chemokine-mediated activation of G protein-coupled receptors CXCR1/2 promotes tumor growth, invasion, inflammation and metastasis. Repertaxin, a CXCR1/2 small-molecule inhibitor, has been shown to attenuate many of these tumor-associated processes. The present study aimed to investigate the effects of repertaxin alone and in combination with 5-fluorouracil (5-FU) on the malignant behavior of gastric cancer and the potential mechanisms. Gastric cancer MKN45 cells were treated in vitro with repertaxin and 5-FU, either alone or in combination. MTT and colony formation assay were performed to assess proliferation. Cell cycle progression and apoptosis was completed by flow cytometry. Migration and invasion were also assessed by Transwell and wound-healing assay. Western blot analysis and quantitative RT-PCR were performed to determine expression of signaling molecules. MKN45 cells were also grown as xenografts in nude mice. Mice were treated with repertaxin and 5-FU, and tumor volume and weight, angiogenesis, proliferation and apoptosis were monitored. Combination of repertaxin and 5-FU inhibited MKN45 cell proliferation and increased apoptosis better than either agent alone. Similarly, enhanced effect of the combination was also observed in migration and invasion assays. The improved effect of repertaxin and 5-FU was also observed in vivo, as xenograft models treated with both compounds exhibited significantly decreased tumor volume and increased apoptosis. In conclusion, repertaxin inhibited malignant behavior of human gastric cancer MKN45 cells in vitro and in vivo and enhances efficacy of 5-fluorouracil. These data provide rationale that targeting CXCR1/2 with small molecule inhibitors may enhance chemotherapeutic efficacy for the treatment of gastric cancer.
PMCID: PMC4777600  PMID: 26847910
repertaxin; 5-fluorouracil; gastric cancer; CXCR1; CXCR2
8.  Enterohepatic Helicobacter Species as a Potential Causative Factor in Inflammatory Bowel Disease 
Medicine  2015;94(45):e1773.
The Helicobacter species in the gut microbiota comprise Helicobacter pylori (H pylori) and enterohepatic Helicobacter species (EHS), which can colonize the intestinal mucosa. However, it is unclear whether EHS are associated with inflammatory bowel disease (IBD). Therefore, we conducted this meta-analysis to examine the association between EHS and IBD.
PubMed, Scopus, Cochrane Library, and Web of Science databases, as well as abstracts from conference proceedings were searched to identify studies that used polymerase chain reaction to detect Helicobacter species in intestinal samples from patients with IBD.
After screening, we carefully reviewed 20 of the 2955 identified studies, and performed a meta-analysis of the findings from 14 studies (11 adult studies and 3 pediatric studies) using STATA v12.0. These studies evaluated 1407 individuals, including 433 patients with Crohn's disease, 306 patients with ulcerative colitis, and 668 controls. The prevalence of Helicobacter species was higher among the patients with IBD, compared to that among the controls, which corresponded to a pooled risk ratio (RR) of 1.59 (95% confidence interval [CI]: 1.12–2.27). The RRs for adult and pediatric patients with IBD were 1.61 (95% CI: 1.03–2.52) and 1.76 (95% CI: 1.17–2.64), respectively. Compared to the controls, the patients with IBD tended to have a higher prevalence of EHS in the intestinal mucosa (RR: 2.01, 95% CI: 1.36–2.98), although the prevalence of H pylori was not significantly higher (RR: 1.22, 95% CI: 0.77–1.95). Compared to the controls, the RRs for EHS in patients with Crohn's disease and ulcerative colitis were 1.72 (95% CI: 1.20–2.47) and 3.27 (95% CI: 0.93–11.44), respectively.
It appears that EHS was associated with IBD, while intestinal H pylori infection was not significantly associated with IBD. Further studies are needed to determine the involvement of EHS in the microbiological etiology of IBD.
PMCID: PMC4912244  PMID: 26559250
9.  TGF-β1 Reduces miR-29a Expression to Promote Tumorigenicity and Metastasis of Cholangiocarcinoma by Targeting HDAC4 
PLoS ONE  2015;10(10):e0136703.
Transforming growth factor β1 (TGF-β1) and miRNAs play important roles in cholangiocarcinoma progression. In this study, miR-29a level was found significantly decreased in both cholangiocarcinoma tissues and tumor cell lines. TGF-β1 reduced miR-29a expression in tumor cell lines. Furthermore, anti-miR-29a reduced the proliferation and metastasis capacity of cholangiocarcinoma cell lines in vitro, overexpression of miR-29a counteracted TGF-β1-mediated cell growth and metastasis. Subsequent investigation identified HDAC4 is a direct target of miR-29a. In addition, restoration of HDAC4 attenuated miR-29a-mediated inhibition of cell proliferation and metastasis. Conclusions: TGF-β1/miR-29a/HDAC4 pathway contributes to the pathogenesis of cholangiocarcinoma and our data provide new therapeutic targets for cholangiocarcinoma.
PMCID: PMC4595145  PMID: 26441331
10.  Lack of association between CD14-159 C/T polymorphism and acute pancreatitis: a meta-analysis 
The CD14-159 C/T polymorphism has been implicated in susceptibility to acute pancreatitis (AP), but the results were inconclusive. The present meta-analysis aimed to explore the correlation between CD14-159 C/T polymorphism and AP risk. All eligible case-control studies published up to November 10th, 2014 were identified by searching PubMed, Web of Science, CNKI, and WanFang databases. Two reviewers independently identified the literature according to inclusion and exclusion criteria. Meta-analysis was performed using RevMan 5.2 and Stata 12.0 software. A total of five studies comprising 1211 cases and 932 controls were included. Overall, no significant association between CD14-159 C/T polymorphism and AP risk was found under all four genetic models [CT + TT vs CC: OR = 1.09, 95% CI (0.91, 1.31); TT vs CT + CC: OR = 1.04, 95% CI (0.83, 1.29); CT vs CC: OR = 1.08, 95% CI (0.89, 1.32); TT vs CC: OR = 1.15, 95% CI (0.88, 1.49)]; In stratification analysis by disease severity, we also failed to detect any association between CD14-159C/T polymorphism and the risk of mild AP (MAP) or severe AP (SAP); In subgroup analysis by ethnicity, similar results were observed in Asian and European populations. This meta-analysis suggested that the CD14-159C/T polymorphism is not associated with the susceptibility of acute pancreatitis.
PMCID: PMC4443155  PMID: 26064321
CD14; acute pancreatitis; polymorphism; meta-analysis
11.  Endemic and Imported Measles Virus–Associated Outbreaks among Adults, Beijing, China, 2013 
Emerging Infectious Diseases  2015;21(3):477-479.
In 2013, a resurgence of measles occurred in Beijing, China. The outbreaks occurred among adults and were associated with endemic genotype H1 and imported genotype D8 viruses. Migrant workers were disproportionately represented in the outbreaks; thus, vaccinating such workers against measles may be an effective strategy toward the elimination of this disease.
PMCID: PMC4344261  PMID: 25695536
adults; measles; outbreak; genotype H1; genotype D8; Beijing; China; viruses; endemic measles; imported measles
12.  An open science resource for establishing reliability and reproducibility in functional connectomics 
Zuo, Xi-Nian | Anderson, Jeffrey S | Bellec, Pierre | Birn, Rasmus M | Biswal, Bharat B | Blautzik, Janusch | Breitner, John C.S | Buckner, Randy L | Calhoun, Vince D | Castellanos, F. Xavier | Chen, Antao | Chen, Bing | Chen, Jiangtao | Chen, Xu | Colcombe, Stanley J | Courtney, William | Craddock, R Cameron | Di Martino, Adriana | Dong, Hao-Ming | Fu, Xiaolan | Gong, Qiyong | Gorgolewski, Krzysztof J | Han, Ying | He, Ye | He, Yong | Ho, Erica | Holmes, Avram | Hou, Xiao-Hui | Huckins, Jeremy | Jiang, Tianzi | Jiang, Yi | Kelley, William | Kelly, Clare | King, Margaret | LaConte, Stephen M | Lainhart, Janet E | Lei, Xu | Li, Hui-Jie | Li, Kaiming | Li, Kuncheng | Lin, Qixiang | Liu, Dongqiang | Liu, Jia | Liu, Xun | Liu, Yijun | Lu, Guangming | Lu, Jie | Luna, Beatriz | Luo, Jing | Lurie, Daniel | Mao, Ying | Margulies, Daniel S | Mayer, Andrew R | Meindl, Thomas | Meyerand, Mary E | Nan, Weizhi | Nielsen, Jared A | O’Connor, David | Paulsen, David | Prabhakaran, Vivek | Qi, Zhigang | Qiu, Jiang | Shao, Chunhong | Shehzad, Zarrar | Tang, Weijun | Villringer, Arno | Wang, Huiling | Wang, Kai | Wei, Dongtao | Wei, Gao-Xia | Weng, Xu-Chu | Wu, Xuehai | Xu, Ting | Yang, Ning | Yang, Zhi | Zang, Yu-Feng | Zhang, Lei | Zhang, Qinglin | Zhang, Zhe | Zhang, Zhiqiang | Zhao, Ke | Zhen, Zonglei | Zhou, Yuan | Zhu, Xing-Ting | Milham, Michael P
Scientific Data  2014;1:140049.
Efforts to identify meaningful functional imaging-based biomarkers are limited by the ability to reliably characterize inter-individual differences in human brain function. Although a growing number of connectomics-based measures are reported to have moderate to high test-retest reliability, the variability in data acquisition, experimental designs, and analytic methods precludes the ability to generalize results. The Consortium for Reliability and Reproducibility (CoRR) is working to address this challenge and establish test-retest reliability as a minimum standard for methods development in functional connectomics. Specifically, CoRR has aggregated 1,629 typical individuals’ resting state fMRI (rfMRI) data (5,093 rfMRI scans) from 18 international sites, and is openly sharing them via the International Data-sharing Neuroimaging Initiative (INDI). To allow researchers to generate various estimates of reliability and reproducibility, a variety of data acquisition procedures and experimental designs are included. Similarly, to enable users to assess the impact of commonly encountered artifacts (for example, motion) on characterizations of inter-individual variation, datasets of varying quality are included.
PMCID: PMC4421932  PMID: 25977800
13.  Evolutionary genetics of genotype H1 measles viruses in China from 1993 to 2012 
The Journal of General Virology  2014;95(Pt 9):1892-1899.
Virologic surveillance is a critical component of measles management. One of the criteria for verification of elimination of endemic measles is genetic analysis of wild-type viruses to demonstrate lack of an indigenous genotype. Measles is yet to be eliminated in China, and genotype H1 has been detected continuously since virologic surveillance was initiated in 1993. Virologic surveillance has been very active in China, providing a unique opportunity to conduct a detailed study of the evolution of a single, endemic genotype over a timespan of nearly two decades. Phylogenetic analysis performed on the 450 nt coding sequence for the C-terminal 150 amino acids of the nucleoprotein (N-450), fusion (F) gene and haemagglutinin (H) gene confirmed the continued circulation of genotype H1 viruses for 19 years. No evidence of selective pressure for the H protein was found. The substitution rates ranged from 0.75×10−3 substitutions site−1 year−1 for H to 1.65×10−3 substitutions site−1 year−1 for N-450. The time of most recent common ancestor (TMRCA) for genotype H1 was estimated as approximately 1985 (95 % highest probability density, 1979–1989). Finally, the overall diversity of measles sequences from China decreased from 2005 to 2012, coincident with a substantial decrease in measles cases. The results suggest that detailed evolutionary analyses should facilitate the documentation of eventual measles elimination in China. Moreover, the molecular approaches used in this study can be applied in other countries approaching measles elimination.
PMCID: PMC4135087  PMID: 24914068
14.  Clinicopathologic characteristics and prognostic value of various histological types in advanced gastric cancer 
The prognostic value of histological types in gastric cancer is not well defined. This study aims to clarify the clinicopathologic features of various WHO histological types and their prognostic significance in advanced gastric cancer (AGC). We retrospectively reviewed 741 patients with gastric cancer in our hospital from 1997 to 2007. The AGC (741 cases) were divided into five histological types: well-differentiated carcinoma (WD), moderately differentiated carcinoma (MD), poorly differentiated carcinoma (PD), mucinous carcinoma (MC), and signet ring cell carcinoma (SRC). The various AGC histological types presented significant differences in their clinical and tumor features. The five-year survival rates of patients with WD, MD, PD, MC, and SRC were 87.1%, 57.1%, 50.6%, 62.7%, and 43.4%, respectively (P=0.012). Multivariate analysis showed that cell differentiation, age, depth of invasion, and lymph node metastasis were independent prognostic factors in AGC, whereas MC and SRC were not. Cell differentiation is related to tumor aggression or patient stage. Advanced stage SRC carcinoma had more aggressive features and worse prognosis than the other types. MC carcinoma survival is correlated with the stage at diagnosis. The degree of cell differentiation is an important predictor of survival in AGC.
PMCID: PMC4203181  PMID: 25337210
Advanced gastric cancer; histologic type; prognosis; cell differentiation
15.  Vascular Endothelial Growth Factor expression in peripheral blood of patients with pregnancy induced hypertension syndrome and its clinical significance 
Objective: This study was conducted was to detect vascular endothelial growth factor (VEGF) levels in peripheral blood of patients with pregnancy-induced hypertension (PIH) syndrome and to investigate VEGF correlation with PIH occurrence.
Methods: Double-antibody enzyme-linked immunosorbent assay and fluorescent quantitative polymerase chain reaction were used to detect VEGF levels in the peripheral blood of non-pregnant women (normal group, 30 cases), normal pregnant women (pregnancy group, 30 cases) and PIH patients (PIH group, 30 cases).
Results: VEGF level in the pregnancy group was significantly higher than in the normal group, and the difference between these two groups was significant (P < 0.001). In the pregnancy group, VEGF reached the maximum level at the metaphase stage of pregnancy and started to decrease at advanced pregnancy. VEGF level in the PIH group was significantly lower than in the pregnancy group at advanced pregnancy (P < 0.01), and VEGF level significantly and gradually decreased with PIH aggravation (P < 0.05).
Conclusions: The significant decrease of VEGF level after pregnancy was possibly an important factor of PIH pathogenesis.
PMCID: PMC4048521  PMID: 24948994
Cardiovascular; Hypertension; Pregnancy complications; Vascular endothelial growth factor
16.  Pediatric Colonoscopy in South China: A 12-Year Experience in a Tertiary Center 
PLoS ONE  2014;9(4):e95933.
To investigate: 1) the demographics and clinical characteristics, 2) the findings, and 3) the safety and effectiveness in a cohort of Chinese pediatric patients undergoing colonoscopy.
The study participants were consecutive patients aged ≤14 years old that underwent their first colonoscopy in the endoscopy center at the First Affiliated Hospital, Sun Yat-sen University between Jan. 1, 2001 and Dec. 31, 2012. Demographic, clinical, endoscopic, and pathological findings were collected.
The cohort consisted of 322 patients, including 218 boys (67.7%) and 104 girls (32.3%). The median age was 8.0 years old and ranged from 9 months to 14 years old. Hematochezia (48.8%) and abdominal pain/discomfort (41.3%) were the most common presentations preceding pediatric colonoscopy. The caecal intubation success rate was 96.3%. No serious complications occurred during the procedures. A total of 227 patients (70.5%) received a positive diagnosis under endoscopy, including 138 patients with polyps and 53 patients with inflammatory bowel disease (IBD). Among the patients with polyps, 71.0% were juvenile polyps. Comparisons between years 2001–2006 and 2007–2012 showed that the IBD detection rate increased significantly (4.6% vs. 22.4%, P<0.001), while the opposite occurred for the polyp detection rate (73.1% vs. 27.6%, P<0.001).
Colonoscopy in pediatric patients is a safe and effective procedure. Polyps are the primary finding during colonoscopy. In South China there has been an increase in pediatric patients diagnosed with IBD over the past decade. However, a large epidemiological study is needed to confirm our findings.
PMCID: PMC3997494  PMID: 24759776
17.  Vitamin E Facilitates the Inactivation of the Kinase Akt by the Phosphatase PHLPP1 
Science signaling  2013;6(267):ra19.
Vitamin E is a fat-soluble vitamin that includes isomers of tocopherols and tocotrienols which are known for their antioxidant properties. Tocopherols are the predominant form encountered in the diet and through supplementation, and have garnered interest for their potential cancer therapeutic and chemopreventive effects, which include the dephosphorylation of Akt, a serine/threonine kinase that plays a pivotal role in important cellular processes, such as cell growth, survival, metabolism and motility. Full catalytic activation of Akt requires phosphorylation at both Thr308 and Ser473. Dephosphorylation of Ser473 drastically reduces Akt catalytic activity and the number of downstream substrates it can regulate. The mechanism by which α- and γ-tocopherol facilitate the selective dephosphorylation of the kinase Akt at Ser473 was investigated. We showed that this site-specific Akt dephosphorylation was mediated through the pleckstrin homology (PH) domain-dependent recruitment to the plasma membrane of Akt and PHLPP1 (PH domain leucine-rich repeat protein phosphatase, isoform 1), a phosphatase that dephosphorylates Akt at Ser473. The ability of α- and γ-tocopherol to induce PHLPP-mediated Akt inhibition established PHLPP as a “druggable” target. We structurally optimized these tocopherols to obtain derivatives with greater in vitro potency and in vivo tumor-suppressive activity in two prostate xenograft tumor models. Binding affinities for the PH domains of Akt and PHLPP1 were greater than for other PH domain-containing proteins, which may underlie the preferential membrane recruitment of these proteins. Molecular modeling revealed the structural determinants of the interaction with the PH domain of Akt that may inform strategies for continued structural optimization. These findings describe a mechanism by which tocopherols facilitate the dephosphorylation of Akt at Ser473, thereby providing insights into the mode of antitumor action of tocopherols and a rationale for the translational development of tocopherols into novel PH domain-targeted Akt inhibitors.
PMCID: PMC3910367  PMID: 23512990
18.  Lesions of Cholinergic Pedunculopontine Tegmental Nucleus Neurons Fail to Affect Cocaine or Heroin Self-Administration or Conditioned Place Preference in Rats 
PLoS ONE  2014;9(1):e84412.
Cholinergic input to the ventral tegmental area (VTA) is known to contribute to reward. Although it is known that the pedunculopontine tegmental nucleus (PPTg) provides an important source of excitatory input to the dopamine system, the specific role of PPTg cholinergic input to the VTA in cocaine reward has not been previously determined. We used a diphtheria toxin conjugated to urotensin-II (Dtx::UII), the endogenous ligand for urotensin-II receptors expressed by PPTg cholinergic but not glutamatergic or GABAergic cells, to lesion cholinergic PPTg neurons. Dtx::UII toxin infusion resulted in the loss of 95.78 (±0.65)% of PPTg cholinergic cells but did not significantly alter either cocaine or heroin self-administration or the development of cocaine or heroin conditioned place preferences. Thus, cholinergic cells originating in PPTg do not appear to be critical for the rewarding effects of cocaine or of heroin.
PMCID: PMC3897371  PMID: 24465410
19.  Genetic Characterization of the Hemagglutinin Genes of Wild-Type Measles Virus Circulating in China, 1993–2009 
PLoS ONE  2013;8(9):e73374.
China experienced several large measles outbreaks in the past two decades, and a series of enhanced control measures were implemented to achieve the goal of measles elimination. Molecular epidemiologic surveillance of wild-type measles viruses (MeV) provides valuable information about the viral transmission patterns. Since 1993, virologic surveillnace has confirmed that a single endemic genotype H1 viruses have been predominantly circulating in China. A component of molecular surveillance is to monitor the genetic characteristics of the hemagglutinin (H) gene of MeV, the major target for virus neutralizing antibodies.
Principal Findings
Analysis of the sequences of the complete H gene from 56 representative wild-type MeV strains circulating in China during 1993–2009 showed that the H gene sequences were clustered into 2 groups, cluster 1 and cluster 2. Cluster1 strains were the most frequently detected cluster and had a widespread distribution in China after 2000. The predicted amino acid sequences of the H protein were relatively conserved at most of the functionally significant amino acid positions. However, most of the genotype H1 cluster1 viruses had an amino acid substitution (Ser240Asn), which removed a predicted N-linked glycosylation site. In addition, the substitution of Pro397Leu in the hemagglutinin noose epitope (HNE) was identified in 23 of 56 strains. The evolutionary rate of the H gene of the genotype H1 viruses was estimated to be approximately 0.76×10−3 substitutions per site per year, and the ratio of dN to dS (dN/dS) was <1 indicating the absence of selective pressure.
Although H genes of the genotype H1 strains were conserved and not subjected to selective pressure, several amino acid substitutions were observed in functionally important positions. Therefore the antigenic and genetic properties of H genes of wild-type MeVs should be monitored as part of routine molecular surveillance for measles in China.
PMCID: PMC3779233  PMID: 24073194
20.  PDLIM5 gene polymorphisms and short term antidepressant response in Chinese major depressive disorders 
Several investigations have suggested that PDLIM5 plays a key role in the pathophysiology of major depressive disorder (MDD), and that PDLIM5 might be a therapeutic target for the action of antidepressant. In this study, we sought to investigate whether variations of PDLIM5 gene sequence could predict response to antidepressants in MDD patients. We selected 3 SNPs (rs10008257, rs2433320, 2452600) of PDLIM5 gene, and performed an association analysis of PDLIM5 and the efficacy of fluoxetine treatment in 185 Han Chinese MDD patients. The results show that the rs2433320 of PDLIM5 gene are associated with fluoxetine therapeutic response in MDD patients (X2 = 8.2960, df = 2, P = 0.0145) after correction with the Bonferroni multiple test, the HAMD score of the GG genotype group was significantly lower than that of the AA and AG genotype group at 1, 2, 4 and 6 weeks. The results support the idea that the PDLIM5 gene is likely to be involved in the antidepressant response in MDD.
PMCID: PMC3762623  PMID: 24040476
PDLIM5; antidepressant; pharmacogenetics; major depressive disorder
21.  Negative life events and corticotropin-releasing-hormone receptor1 gene in recurrent major depressive disorder 
Scientific Reports  2013;3:1548.
Major depressive disorder (MDD) is a long-term, recurrent condition that often takes a chronic course. It seems imperative that research should be focused on gaining a better understanding of what predicts recurrent MDD. As a major mediator of the stress response, corticotropin-releasing-hormone receptor 1 (CRHR1) has been demonstrated to be an important contributor to the pathogenesis of MDD. In this study, we show a significant increase in the G-allele (rs242939) of the CRHR1 gene in the recurrent MDD group compared with the control group, and an overrepresentation of G-G-T hyplotype of the CRHR1 gene in recurrent MDD. We also demonstrate the interaction of the CRHR1 gene and negative life events in recurrent MDD. These results suggest that the CRHR1 gene could modify the susceptibility to developing recurrent MDD following negative life events in adulthood.
PMCID: PMC3607833  PMID: 23529111
22.  Human Parainfluenza Virus-Associated Respiratory Tract Infection among Children and Genetic Analysis of HPIV-3 Strains in Beijing, China 
PLoS ONE  2012;7(8):e43893.
The relevance of human parainfluenza viruses (HPIVs) to the epidemiology of acute respiratory infections (ARI) in China is unclear. From May 2008 to September 2010, 443 nasopharyngeal aspirates (NPAs) from hospitalized pediatric patients (age from 1 to 93 months) in Beijing were collected and screened for HPIVs and other common respiratory viruses by real-time RT-PCR. Sixty-two of 443 samples were positive for HPIVs with 4 positive for HPIV-2 and 58 positive for HPIV-3, indicating that HPIV-3 was the predominant virus present during the study period. A phylogenetic tree based on all the available HN (hemagglutinin-neuraminidase) sequences of HPIV-3 indicated that three distinct clusters (A,B, and C) were circulating with some temporal and regional clustering. Cluster C was further divided into sub-clusters, C1, C2, C3 and C4. HPIV-3 from Beijing isolates belonged to sub-cluster C3, and were grouped with the isolates from two Provinces of China and the neighboring country of Japan. Genetic analysis based on entire HN gene revealed that the HPIV-3 isolates from Beijing were highly similar with 97.2%–100% identity at the nucleotide level and these could be divided into two closely related lineages, C3a and C3b. These findings suggested that there was co-circulation of multiple lineages of HPIV-3 in the Beijing region during the study period. This is the first study to describe the epidemiology and molecular characterization of HPIVs in China.
PMCID: PMC3429441  PMID: 22937119
23.  Single Endemic Genotype of Measles Virus Continuously Circulating in China for at Least 16 Years 
PLoS ONE  2012;7(4):e34401.
The incidence of measles in China from 1991 to 2008 was reviewed, and the nucleotide sequences from 1507 measles viruses (MeV) isolated during 1993 to 2008 were phylogenetically analyzed. The results showed that measles epidemics peaked approximately every 3 to 5 years with the range of measles cases detected between 56,850 and 140,048 per year. The Chinese MeV strains represented three genotypes; 1501 H1, 1 H2 and 5 A. Genotype H1 was the predominant genotype throughout China continuously circulating for at least 16 years. Genotype H1 sequences could be divided into two distinct clusters, H1a and H1b. A 4.2% average nucleotide divergence was found between the H1a and H1b clusters, and the nucleotide sequence and predicted amino acid homologies of H1a viruses were 92.3%–100% and 84.7%–100%, H1b were 97.1%–100% and 95.3%–100%, respectively. Viruses from both clusters were distributed throughout China with no apparent geographic restriction and multiple co-circulating lineages were present in many provinces. Cluster H1a and H1b viruses were co-circulating during 1993 to 2005, while no H1b viruses were detected after 2005 and the transmission of that cluster has presumably been interrupted. Analysis of the nucleotide and predicted amino acid changes in the N proteins of H1a and H1b viruses showed no evidence of selective pressure. This study investigated the genotype and cluster distribution of MeV in China over a 16-year period to establish a genetic baseline before MeV elimination in Western Pacific Region (WPR). Continuous and extensive MeV surveillance and the ability to quickly identify imported cases of measles will become more critical as measles elimination goals are achieved in China in the near future. This is the first report that a single endemic genotype of measles virus has been found to be continuously circulating in one country for at least 16 years.
PMCID: PMC3332093  PMID: 22532829
24.  High-Affinity Peptide Against MT1-MMP for In Vivo Tumor Imaging 
Membrane type-1 matrix metalloproteinase (MT1-MMP) is a key member of the matrix metalloproteinase (MMP) family. It participates in pericellular proteolysis of extracellular matrix (ECM) macromolecules and is essential for many biological and pathological processes, such as tumor development, angiogenesis and metastasis. A ligand that specifically binds to MT1-MMP may facilitate the labeling of this molecule, allow imaging at the cellular and organism levels, and provide a means for targeted drug delivery specific to MT1-MMP. A non-substrate MT1-MMP binding peptide was identified by screening a Ph. D.™ - 12 phage display peptide library and conjugated with near-infrared fluorescent (NIRF) dye Cy5.5 for tumor imaging. Peptide HWKHLHNTKTFL (denoted as MT1-AF7p) showed high MT1-MMP binding affinity. Computer modeling verified that MT1-AF7p binds to the MT-loop region of MT1-MMP and interacts with MT1-MMP through hydrogen bonding and hydrophobic interactions. MDA-MB-435 xenografts with high MT1-MMP expression had significantly higher tumor accumulation and better tumor contrast than the low MT1-MMP expressing A549 xenografts after intravenous injection of Cy5.5-MT1-AF7p. A novel non-substrate affinity peptide MT1-AF7p was found for MT1-MMP high affinity and specificity. Using NIRF imaging, we have demonstrated specific targeting of MT1-AF7p to MT1-MMP-expressing tumors. Thus, MT1-AF7p is an important tool for noninvasive monitoring of MT1-MMP expression in tumors, and it shows great potential as an imaging agent for MT1-MMP – positive tumors.
PMCID: PMC3085951  PMID: 21295090
matrix metalloproteinase; MT1-MMP (MMP-14); phage display peptide library; near-infrared fluorescence optical imaging
25.  Interaction between CRHR1 and BDNF Genes Increases the Risk of Recurrent Major Depressive Disorder in Chinese Population 
PLoS ONE  2011;6(12):e28733.
An important etiological hypothesis about depression is stress has neurotoxic effects that damage the hippocampal cells. Corticotropin-releasing hormone (CRH) regulates brain-derived neurotrophic factor (BDNF) expression through influencing cAMP and Ca2+ signaling pathways during the course. The aim of this study is to examine the single and combined effects of CRH receptor 1 (CRHR1) and BDNF genes in recurrent major depressive disorder (MDD).
Methodology/Principal Finding
The sample consists of 181 patients with recurrent MDD and 186 healthy controls. Whether genetic variations interaction between CRHR1 and BDNF genes might be associated with increased susceptibility to recurrent MDD was studied by using a gene-based association analysis of single-nucleotide polymorphisms (SNPs). CRHR1 gene (rs1876828, rs242939 and rs242941) and BDNF gene (rs6265) were identified in the samples of patients diagnosed with recurrent MDD and matched controls. Allelic association between CRHR1 rs242939 and recurrent MDD was found in our sample (allelic: p = 0.018, genotypic: p = 0.022) with an Odds Ratio 0.454 (95% CI 0.266–0.775). A global test of these four haplotypes showed a significant difference between recurrent MDD group and control group (chi-2 = 13.117, df = 3, P = 0.016. Furthermore, BDNF and CRHR1 interactions were found in the significant 2-locus, gene–gene interaction models (p = 0.05) using a generalized multifactor dimensionality reduction (GMDR) method.
Our results suggest that an interaction between CRHR1 and BDNF genes constitutes susceptibility to recurrent MDD.
PMCID: PMC3237493  PMID: 22194899

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