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1.  Experimental chronic hepatitis B infection of neonatal tree shrews (Tupaia belangeri chinensis): A model to study molecular causes for susceptibility and disease progression to chronic hepatitis in humans 
Virology Journal  2012;9:170.
Hepatitis B virus (HBV) infection continues to be an escalating global health problem. Feasible and effective animal models for HBV infection are the prerequisite for developing novel therapies for this disease. The tree shrew (Tupaia) is a small animal species evolutionary closely related to humans, and thus is permissive to certain human viral pathogens. Whether tree shrews could be chronically infected with HBV in vivo has been controversial for decades. Most published research has been reported on adult tree shrews, and only small numbers of HBV infected newborn tree shrews had been observed over short time periods. We investigated susceptibility of newborn tree shrews to experimental HBV infection as well as viral clearance over a protracted time period.
Forty-six newborn tree shrews were inoculated with the sera from HBV-infected patients or tree shrews. Serum and liver samples of the inoculated animals were periodically collected and analyzed using fluorescence quantitative polymerase chain reaction, enzyme-linked immunosorbent assay, Southern blot, and immunohistochemistry. Six tree shrews were confirmed and four were suspected as chronically HBV-infected for more than 48 (up to 228) weeks after inoculation, including three that had been inoculated with serum from a confirmed HBV-infected tree shrew.
Outbred neonatal tree shrews can be long-term chronically infected with HBV at a frequency comparable to humans. The model resembles human disease where also a smaller proportion of infected individuals develop chronic HBV related disease. This model might enable genetic and immunologic investigations which would allow determination of underlying molecular causes favoring susceptibility for chronic HBV infection and disease establishment vs. viral clearance.
PMCID: PMC3511180  PMID: 22913805
Tree shrew (Tupaia); Hepatitis B virus; Chronic infection
2.  Magnetic microbubble-mediated ultrasound-MRI registration based on robust optical flow model 
BioMedical Engineering OnLine  2015;14(Suppl 1):S14.
As a dual-modality contrast agent, magnetic microbubbles (MMBs) can not only improve contrast of ultrasound (US) image, but can also serve as a contrast agent of magnetic resonance image (MRI). With the help of MMBs, a new registration method between US image and MRI is presented.
In this method, MMBs were used in both ultrasound and magnetic resonance imaging process to enhance the most important information of interest. In order to reduce the influence of the speckle noise to registration, semi-automatic segmentations of US image and MRI were carried out by using active contour model. After that, a robust optical flow model between US image segmentation (floating image) and MRI segmentation (reference image) was built, and the vector flow field was estimated by using the Coarse-to-fine Gaussian pyramid and graduated non-convexity (GNC) schemes.
Qualitative and quantitative analyses of multiple group comparison experiments showed that registration results using all methods tested in this paper without MMBs were unsatisfactory. On the contrary, the proposed method combined with MMBs led to the best registration results.
The proposed algorithm combined with MMBs contends with larger deformation and performs well not only for local deformation but also for global deformation. The comparison experiments also demonstrated that ultrasound-MRI registration using the above-mentioned method might be a promising method for obtaining more accurate image information.
PMCID: PMC4306103  PMID: 25602434
3.  In Vivo Bone Regeneration Using Tubular Perfusion System Bioreactor Cultured Nanofibrous Scaffolds 
Tissue Engineering. Part A  2013;20(1-2):139-146.
The use of bioreactors for the in vitro culture of constructs for bone tissue engineering has become prevalent as these systems may improve the growth and differentiation of a cultured cell population. Here we utilize a tubular perfusion system (TPS) bioreactor for the in vitro culture of human mesenchymal stem cells (hMSCs) and implant the cultured constructs into rat femoral condyle defects. Using nanofibrous electrospun poly(lactic-co-glycolic acid)/poly(ɛ-caprolactone) scaffolds, hMSCs were cultured for 10 days in vitro in the TPS bioreactor with cellular and acellular scaffolds cultured statically for 10 days as a control. After 3 and 6 weeks of in vivo culture, explants were removed and subjected to histomorphometric analysis. Results indicated more rapid bone regeneration in defects implanted with bioreactor cultured scaffolds with a new bone area of 1.23±0.35 mm2 at 21 days compared to 0.99±0.43 mm2 and 0.50±0.29 mm2 in defects implanted with statically cultured scaffolds and acellular scaffolds, respectively. At the 21 day timepoint, statistical differences (p<0.05) were only observed between defects implanted with cell containing scaffolds and the acellular control. After 42 days, however, defects implanted with TPS cultured scaffolds had the greatest new bone area with 1.72±0.40 mm2. Defects implanted with statically cultured and acellular scaffolds had a new bone area of 1.26±0.43 mm2 and 1.19±0.33 mm2, respectively. The increase in bone growth observed in defects implanted with TPS cultured scaffolds was statistically significant (p<0.05) when compared to both the static and acellular groups at this timepoint. This study demonstrates the efficacy of the TPS bioreactor to improve bone tissue regeneration and highlights the benefits of utilizing perfusion bioreactor systems to culture MSCs for bone tissue engineering.
PMCID: PMC3875202  PMID: 23865551
4.  Concise Review: Cell-Based Strategies in Bone Tissue Engineering and Regenerative Medicine 
Cellular strategies play an important role in bone tissue engineering and regenerative medicine (BTE/RM). Variability in cell culture procedures (e.g., cell types, cell isolation and expansion, cell seeding methods, and preculture conditions before in vivo implantation) may influence experimental outcome. The present review provides an overview of the critical procedures during in vitro and in vivo phases for cell-based strategies (both monoculture and coculture) in BTE/RM.
Cellular strategies play an important role in bone tissue engineering and regenerative medicine (BTE/RM). Variability in cell culture procedures (e.g., cell types, cell isolation and expansion, cell seeding methods, and preculture conditions before in vivo implantation) may influence experimental outcome. Meanwhile, outcomes from initial clinical trials are far behind those of animal studies, which is suggested to be related to insufficient nutrient and oxygen supply inside the BTE/RM constructs as some complex clinical implementations require bone regeneration in too large a quantity. Coculture strategies, in which angiogenic cells are introduced into osteogenic cell cultures, might provide a solution for improving vascularization and hence increasing bone formation for cell-based constructs. So far, preclinical studies have demonstrated that cell-based tissue-engineered constructs generally induce more bone formation compared with acellular constructs. Further, cocultures have been shown to enhance vascularization and bone formation compared with monocultures. However, translational efficacy from animal studies to clinical use requires improvement, and the role implanted cells play in clinical bone regeneration needs to be further elucidated. In view of this, the present review provides an overview of the critical procedures during in vitro and in vivo phases for cell-based strategies (both monoculture and coculture) in BTE/RM to achieve more standardized culture conditions for future studies, and hence enhance bone formation.
PMCID: PMC3902295  PMID: 24300556
Mesenchymal stem cells; Endothelial cells; Bone marrow stromal cells; Adipose stem cells; Vascularization; Tissue regeneration
5.  Brain iron redistribution in mesial temporal lobe epilepsy: a susceptibility-weighted magnetic resonance imaging study 
BMC Neuroscience  2014;15(1):117.
The roles of iron in epilepsy and its pathophysiological significance are poorly understood, especially whether iron levels are abnormal in subcortcal structures. This study aims to demonstrate whole-brain iron alterations and its clinical relevancies in mesial temporal lobe epilepsy (mTLE) in vivo, using susceptibility-weighted magnetic resonance imaging (SWI).
We studied 62 patients with mTLE and 62 healthy controls. Brain iron concentration was quantified using SWI phase values. Voxel-wise analysis was carried out to compare iron levels between mTLE and controls, and to assess the relationship between altered iron concentration and clinical parameters in mTLE.
Patients with mTLE showed decreases of iron levels in the subcortical structures such as substantia nigra, red nucleus, and basal ganglia. Conversely, iron levels were decreased in the cortex. Subcortical iron levels were negatively correlated to those in the cortex. Moreover, cortical and basal ganglia iron levels were related to clinical variables including epilepsy duration, age at seizures onset, and histories of precipitating factors.
Our SWI findings suggest a redistribution of iron between subcortical and cortical structures in mTLE. The degree of redistribution is affected by both progression of epilepsy and precipitating factors. Investigation on brain iron redistribution offers new insights into the pathogenesis of mTLE, and may be a potential biomarker for monitoring the clinical progression of epilepsy.
Electronic supplementary material
The online version of this article (doi:10.1186/s12868-014-0117-3) contains supplementary material, which is available to authorized users.
PMCID: PMC4243317  PMID: 25413842
Brain iron; Mesial temporal lobe epilepsy; Susceptibility-weighted magnetic resonance imaging
6.  Biologically inspired flexible quasi-single-mode random laser: An integration of Pieris canidia butterfly wing and semiconductors 
Scientific Reports  2014;4:6736.
Quasi-periodic structures of natural biomaterial membranes have great potentials to serve as resonance cavities to generate ecological friendly optoelectronic devices with low cost. To achieve the first attempt for the illustration of the underlying principle, the Pieris canidia butterfly wing was embedded with ZnO nanoparticles. Quite interestingly, it is found that the bio-inspired quasi-single-mode random laser can be achieved by the assistance of the skeleton of the membrane, in which ZnO nanoparticles act as emitting gain media. Such unique characteristics can be interpreted well by the Fabry-Perot resonance existing in the window-like quasi-periodic structure of butterfly wing. Due to the inherently promising flexibility of butterfly wing membrane, the laser action can still be maintained during the bending process. Our demonstrated approach not only indicates that the natural biological structures can provide effective scattering feedbacks but also pave a new avenue towards designing bio-controlled photonic devices.
PMCID: PMC4206842  PMID: 25338507
7.  Purification and in vitro antioxidant activities of tellurium-containing phycobiliproteins from tellurium-enriched Spirulina platensis 
Tellurium-containing phycocyanin (Te-PC) and allophycocyanin (Te-APC), two organic tellurium (Te) species, were purified from tellurium-enriched Spirulina platensis by a fast protein liquid chromatographic method. It was found that the incorporation of Te into the peptides enhanced the antioxidant activities of both phycobiliproteins. With fractionation by ammonium sulfate precipitation and hydroxylapatite chromatography, Te-PC and Te-APC could be effectively separated with high purity, and Te concentrations were 611.1 and 625.3 μg g−1 protein in Te-PC and Te-APC, respectively. The subunits in the proteins were identified by using MALDI-TOF-TOF mass spectrometry. Te incorporation enhanced the antioxidant activities of both phycobiliproteins, as examined by 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid assay. Moreover, Te-PC and Te-APC showed dose-dependent protection on erythrocytes against the water-soluble free radical initiator 2,2′-azo(2-asmidinopropane)dihydrochloride-induced hemolysis. In the hepatoprotective model, apoptotic cell death and nuclear condensation induced by tert-butyl hydroperoxide in HepG2 cells was significantly attenuated by Te-PC and Te-APC. Taken together, these results suggest that Te-PC and Te-APC are promising Te-containing proteins with application potential for treatment of diseases related to oxidative stress.
PMCID: PMC4199980  PMID: 25336922
tellurium; phycocyanin; allophycocyanin; purification; antioxidant activity
8.  The PathoChip, a functional gene array for assessing pathogenic properties of diverse microbial communities 
The ISME Journal  2013;7(10):1974-1984.
Pathogens present in the environment pose a serious threat to human, plant and animal health as evidenced by recent outbreaks. As many pathogens can survive and proliferate in the environment, it is important to understand their population dynamics and pathogenic potential in the environment. To assess pathogenic potential in diverse habitats, we developed a functional gene array, the PathoChip, constructed with key virulence genes related to major virulence factors, such as adherence, colonization, motility, invasion, toxin, immune evasion and iron uptake. A total of 3715 best probes were selected from 13 virulence factors, covering 7417 coding sequences from 1397 microbial species (2336 strains). The specificity of the PathoChip was computationally verified, and approximately 98% of the probes provided specificity at or below the species level, proving its excellent capability for the detection of target sequences with high discrimination power. We applied this array to community samples from soil, seawater and human saliva to assess the occurrence of virulence genes in natural environments. Both the abundance and diversity of virulence genes increased in stressed conditions compared with their corresponding controls, indicating a possible increase in abundance of pathogenic bacteria under environmental perturbations such as warming or oil spills. Statistical analyses showed that microbial communities harboring virulence genes were responsive to environmental perturbations, which drove changes in abundance and distribution of virulence genes. The PathoChip provides a useful tool to identify virulence genes in microbial populations, examine the dynamics of virulence genes in response to environmental perturbations and determine the pathogenic potential of microbial communities.
PMCID: PMC3965316  PMID: 23765101
virulence genes; functional gene array; climate warming; oil-contamination; caries
9.  Serum Amyloid A and Clusterin as Potential Predictive Biomarkers for Severe Hand, Foot and Mouth Disease by 2D-DIGE Proteomics Analysis 
PLoS ONE  2014;9(9):e108816.
Hand, foot, and mouth disease (HFMD) affects more than one million children, is responsible for several hundred child deaths every year in China and is the cause of widespread concerns in society. Only a small fraction of HFMD cases will develop further into severe HFMD with neurologic complications. A timely and accurate diagnosis of severe HFMD is essential for assessing the risk of progression and planning the appropriate treatment. Human serum can reflect the physiological or pathological states, which is expected to be an excellent source of disease-specific biomarkers. In the present study, a comparative serological proteome analysis between severe HFMD patients and healthy controls was performed via a two-dimensional difference gel electrophoresis (2D-DIGE) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) strategy. Fifteen proteins were identified as differentially expressed in the sera of the severe HFMD patients compared with the controls. The identified proteins were classified into different groups according to their molecular functions, biological processes, protein classes and physiological pathways by bioinformatics analysis. The up-regulations of two identified proteins, serum amyloid A (SAA) and clusterin (CLU), were confirmed in the sera of the HFMD patients by ELISA assay. This study not only increases our background knowledge about and scientific insight into the mechanisms of HFMD, but also reveals novel potential biomarkers for the clinical diagnosis of severe HFMD.
PMCID: PMC4182520  PMID: 25268271
10.  ANKRD7 and CYTL1 are novel risk genes for alcohol drinking behavior 
Chinese medical journal  2012;125(6):1127-1134.
Alcohol dependence (AD) is a complex disorder characterized by impaired control over drinking. It is determined by both genetic and environmental factors. The recent approach of genome-wide association study (GWAS) is a powerful tool for identifying complex disease-associated susceptibility alleles, however, a few GWASs have been conducted for AD, and their results are largely inconsistent. The present study aimed to screen the loci associated with alcohol-related phenotypes using GWAS technology.
A genome-wide association study with the behavior of regular alcohol drinking and alcohol consumption was performed to identify susceptibility genes associated with AD, using the Affymetrix 500K SNP array in an initial sample consisting of 904 unrelated Caucasian subjects. Then, the initial results in GWAS were replicated in three independent samples: 1972 Caucasians in 593 nuclear families, 761 unrelated Caucasian subjects, and 2955 unrelated Chinese Hans.
Several genes were associated with the alcohol-related phenotypes at the genome-wide significance level, with the ankyrin repeat domain 7 gene (ANKRD7) showing the strongest statistical evidence for regular alcohol drinking and suggestive statistical evidence for alcohol consumption. In addition, certain haplotypes within the ANKRD7 and cytokine-like1 (CYTL1) genes were significantly associated with regular drinking behavior, such as one ANKRD7 block composed of the SNPs rs6466686-rs4295599-rs12531086 (P = 6.51×10–8). The association of alcohol consumption was successfully replicated with rs4295599 in ANKRD7 gene in independent Caucasian nuclear families and independent unrelated Chinese Hans, and with rs16836497 in CYTL1 gene in independent unrelated Caucasians. Meta-analyses based on both the GWAS and replication samples further supported the observed significant associations between the ANKRD7 or CYTL1 gene and alcohol consumption.
The evidence suggests that ANKRD7 and CYTL1 genes may play an important role in the variance in AD risk.
PMCID: PMC4174677  PMID: 22613542
alcohol dependence; ANKRD7; CYTL1; genome-wide association study
11.  Portal vein arterialization technique for liver transplantation patients 
World Journal of Gastroenterology : WJG  2014;20(34):12359-12362.
Liver transplantations were performed on two patients with hepatic failure caused by liver cirrhosis. Hard obsolete thrombi and portal venous sclerosis were observed in the major portal veins of both patients. The arteria colica media of one recipient and the portal vein of the donor were anastomosed end-to-end. The hepatic artery of the first donor was anastomosed end-to end with the gastroduodenal artery of the first recipient; meanwhile, the portal vein of the second donor was simultaneously anastomosed end- to-end with the common hepatic artery of the second recipient. The blood flow of the portal vein, the perfusion of the donor liver and liver function were satisfactory after surgery. Portal vein arterialization might be an effective treatment for patients whose portal vein reconstruction was difficult.
PMCID: PMC4161825  PMID: 25232274
Portal vein arterialization; Liver transplantation; Portal vein; Postoperative complication; Donor
12.  Small nucleolar RNA 113–1 suppresses tumorigenesis in hepatocellular carcinoma 
Molecular Cancer  2014;13(1):216.
Emerging evidence suggests that small nucleolar RNAs (snoRNAs) are involved in tumorigenesis. The roles of small nucleolar RNA 113–1 (SNORD113-1) on the development of hepatocellular carcinoma (HCC) remain unknown.
The expression of SNORD113-1 was measured in 112 HCC tumor tissues using quantitative RT-PCR and compared with expression levels from with paired non-tumor tissues. The effects of SNORD113-1 on HCC tumorigenesis were investigated in HepG2 and Huh7 cells as well as a xenograft nude mouse model. CpG methylation within the promoter region of the SNORD113-1 gene was identified using Sodium bisulfite sequencing. Cancer pathway reporter investigate the mechanism by which SNORD113-1 suppressed tumorigenesis.
SNORD113-1 expression was significantly downregulated in HCC tumors compared with adjacent non-tumor tissues, and downregulation of SNORD113-1 in HCC tumors was significantly associated with worse survival of patients. In addition, CpG methylation at the promoter region of the SNORD113-1 gene was higher in HCC tumors than adjacent non-tumor tissues. Functionally, SNORD113-1 suppressed cancer cell growth in HepG2 and Huh7 cells and in a xenograft nude mouse model. Furthermore, SNORD113-1 inactivated the phosphorylation of ERK1/2 and SMAD2/3 in MAPK/ERK and TGF-β pathways.
SNORD113-1 functions as a tumor suppressor role in HCC and may be important as a potential diagnostic and therapeutic target for HCC.
Electronic supplementary material
The online version of this article (doi:10.1186/1476-4598-13-216) contains supplementary material, which is available to authorized users.
PMCID: PMC4169825  PMID: 25217841
13.  Structure-Based Discovery of Natural Product-Like TNF-α Inhibitors 
Two natural product-like inhibitors of TNF-α have been identified using structure-based virtual screening. These compounds represent only the third and fourth examples of direct target of TNF-α by a small molecule and display comparable potency to the strongest TNF-α inhibitor reported to date.
PMCID: PMC4162403  PMID: 20235259
inhibitors; tumor necrosis factor; virtual screening; natural products; drug discovery
14.  Initial 3-Weeks’ Apixaban Versus Dual-Antiplatelet Therapy (Clopidogrel and Aspirin) Followed by Clopidogrel Alone in High-Risk Patients with Acute Non-Disabling Cerebrovascular Events (ADANCE): Study Protocol for a Randomized Controlled Trial 
Clinical Drug Investigation  2014;34(11):755-761.
Nondisabling cerebrovascular events represent the largest group of cerebrovascular disease with a high risk of recurrent stroke. A recent trial demonstrated that dual-antiplatelet therapy (clopidogrel and aspirin), compared with aspirin monotherapy, reduced the risk of recurrent stroke and was not associated with increased risk of hemorrhagic events. Apixaban, a new oral anticoagulant, has been proven to be as safe and effective as traditional anticoagulants while carrying significantly less risk of intracranial hemorrhage. Patients with transient ischemic attack (TIA)/minor stroke might benefit from apixaban treatment; therefore, an adequately powered randomized study is needed.
Methods and Results
The ADANCE [Apixaban Versus Dual-antiplatelet Therapy (Clopidogrel and Aspirin) in Acute Non-disabling Cerebrovascular Events] study is a randomized, double-blind clinical trial with a target enrollment of 5,500 patients. A 21-day regimen of apixaban or of clopidogrel with aspirin followed by clopidogrel on days 22 through 90 will be administered to randomized participants with acute TIA or minor ischemic stroke. The primary efficacy endpoint is the percentage of patients with any new stroke (ischemic or hemorrhage), including fatal stroke, at day 21. Study visits will be performed on the day of randomization, and at days 7, 22, and 90.
The novel oral anticoagulant apixaban has been widely used with fewer adverse effects than traditional anticoagulants. We designed the ADANCE trial to observe the effects of apixaban on recurrent stroke after TIA or minor stroke. The results should better guide the selection of anticoagulant or dual-antiplatelet therapy for patients with acute TIA or minor ischemic stroke.
PMCID: PMC4210645  PMID: 25200142
15.  Association between Hcy levels and the CBS844ins68 and MTHFR C677T polymorphisms with essential hypertension 
Biomedical Reports  2014;2(6):861-868.
The aim of the present study was to investigate the association between the homocysteine (Hcy) levels and polymorphisms of the CBS844ins68 and MTHFR C677T genes in essential hypertension (EH). The effects of the MTHFR C677T and CBS844ins68 haploid genotypes and the combined genotypes on EH and levels of Hcy were further explored. The polymorphisms of CBS844ins68 and MTHFR C677T genes in 200 EH and 200 normal tensive (NT) patients were detected using polymerase chain reaction-restriction fragment length polymorphism and analysis of the distribution of genotypes. An automated biochemical analyzer was used to measure the plasma Hcy levels and the clinical biochemistry data. The plasma Hcy levels in EH were significantly higher than those of the NT group (P<0.05). There were no significant differences (P>0.05) between males and females. Two genotypes, deletion/deletion (DD) and deletion/insertion (DI), of the CBS844ins68 polymorphism were found in two groups with no clear differences in two genotypes and allele frequency distribution (P>0.05). There were significant differences in the three genotype frequencies (χ2=6.658, χ2=4.410, P<0.05) for MTHFR C677T locus genotypes CC, CT and TT. The Hcy levels in genotypes DD and DI had no significant differences (P>0.05) and the CT and TT types were significantly higher compared to the CC genotype (P<0.05). The CC/DD combined genotype in the two groups was significantly different (P<0.05), and the odds ratio (OR), 0.569 showed that the CC/DD genotype may be a protective factor of hypertension. In the two groups, the Hcy levels for combined genotypes CC/DD, CT/DD, TT/DD and TT/DI were significantly different (P<0.05). The SHEsis software analysis linkage disequilibrium coefficient=0.216, indicates that there is probably a weak linkage for MTHFR C677T and CBS844ins68. Haplotype analysis suggested that the C-D haplotype was negatively correlated with EH (OR, 0.727) and that there was a positive correlation between T-D haplotype and EH (OR, 1.376). MTHFR C677T and CBS844ins68 polymorphisms were present in the populations studied and the CBS844ins68 homozygous mutation was not present. Therefore, there is a correlation between the polymorphisms of the MTHFR C677T gene and EH, and allele T may be one of the predisposing factors. MTHFR C677T and CBS844ins68 may exist with a certain linkage and the T-D haplotype may be a risk factor for EH.
PMCID: PMC4179705  PMID: 25279160
homocysteine; CBS844ins68; MTHFR C677T; polymorphisms
16.  TAp73 and ΔNp73 Have Opposing Roles in 5-aza-2′-Deoxycytidine-Induced Apoptosis in Breast Cancer Cells 
Molecules and Cells  2014;37(8):605-612.
The p73 gene contains an extrinsic P1 promoter and an intrinsic P2 promoter, controlling the transcription of the pro-apoptotic TAp73 isoform and the anti-apoptotic ΔΝp73 isoform, respectively. The DNA methylation status of both promoters act equally in the epigenetic transcriptional regulation of their relevant isoforms. The aim of this study was to analyze the different effects of these p73 isoforms in 5-aza-2′-deoxycytidine (5-aza-dC)-induced apoptosis in breast cancer cells. We investigated the effects of the DNA demethylation agent, 5-aza-dC, on the T-47D breast cancer cell line, and evaluated the methylation status of the p73 promoters and expression of TAp73 and ΔNp73. Furthermore, we assessed the expression of p53 and p73 isoforms in 5-aza-dC-treated T-47D cells and p53 knockout cells. 5-aza-dC induced significant anti-tumor effects in T-47D cells, including inhibition of cell viability, G1 phase arrest and apoptosis. This was associated with p73 promoter demethylation and a concomitant increase in TAp73 mRNA and protein expression. In contrast, the methylation status of promoter P2 was not associated with ΔNp73 mRNA or protein levels. Furthermore, demethylation of P2 failed to inhibit the expression of ΔNp73 with 5-aza-dC in the p53 knockdown cell model. Our study suggests that demethylation of the P1 and P2 promoters has opposite effects on the expression of p73 isoforms, namely up-regulation of TAp73 and down-regulation of ΔΝp73. We also demonstrate that p53 likely contributes to 5-aza-dC-induced ΔNp73 transcriptional inactivation in breast cancer cells.
PMCID: PMC4145372  PMID: 25134538
5-aza-2′-deoxycytidine; breast cancer; methylation; p53; p73
17.  Indolent T-lymphblastic proliferation: report of a case involving the upper aerodigestive tract 
T-lymphoblastic lymphoma (T-LBP) is a high-grade malignant lymphoma, which possesses the characteristic of high metastasis and high mortality without treatment. We are presenting a special T-lymphoblastic proliferation involving in the oropharynx, nasopharynx, sinus and trachea in a patient with local involved about 15-years without systemic dissemination. The immunophenotype of this case was similar to T-LBP. The proliferous cells were positive for terminal deoxynucleotidyl transferase (TdT), CD3, and appeared co-expression CD4 and CD8. No clonal rearrangements of TCRγ and/or TCRβ gene were detected. Indolent T-lymphoblastic proliferations rarely occurred or unusually could not be diagnosed, combing with the relevant literature and clinically indolent manifestation, we interpreted this case as indolent T-lymphoblastic proliferation (iT-LBPs). So far, the mechanism of the T-lymphoblastic proliferations is still uncertain and requires further study.
PMCID: PMC4203261  PMID: 25337290
T-lymphoblastic lymphoma; indolent T-lymphoblastic proliferation; upper aerodigestive tract
18.  Global transcriptome-wide analysis of CIK cells identify distinct roles of IL-2 and IL-15 in acquisition of cytotoxic capacity against tumor 
BMC Medical Genomics  2014;7:49.
Cytokine-induced killer (CIK) cells are an emerging approach of cancer treatment. Our previous study have shown that CIK cells stimulated with combination of IL-2 and IL-15 displayed improved proliferation capacity and tumor cytotoxicity. However, the mechanisms of CIK cell proliferation and acquisition of cytolytic function against tumor induced by IL-2 and IL-15 have not been well elucidated yet.
CIKIL-2 and CIKIL-15 were generated from peripheral blood mononuclear cells primed with IFN-γ, and stimulated with IL-2 and IL-15 in combination with OKT3 respectively. RNA-seq was performed to identify differentially expressed genes, and gene ontology and pathways based analysis were used to identify the distinct roles of IL-2 and IL-15 in CIK preparation.
The results indicated that CIKIL-15 showed improved cell proliferation capacity compared to CIKIL-2. However, CIKIL-2 has exhibited greater tumor cytotoxic effect than CIKIL-15. Employing deep sequencing, we sequenced mRNA transcripts in CIKIL-2 and CIKIL-15. A total of 374 differentially expressed genes (DEGs) were identified including 175 up-regulated genes in CIKIL-15 and 199 up-regulated genes in CIKIL-2. Among DEGs in CIKIL-15, Wnt signaling and cell adhesion were significant GO terms and pathways which related with their functions. In CIKIL-2, type I interferon signaling and cytokine-cytokine receptor interaction were significant GO terms and pathways. We found that the up-regulation of Wnt 4 and PDGFD may contribute to enhanced cell proliferation capacity of CIKIL-15, while inhibitory signal from interaction between CTLA4 and CD80 may be responsible for the weak proliferation capacity of CIKIL-2. Moreover, up-regulated expressions of CD40LG and IRF7 may make for improved tumor cytolytic function of CIKIL-2 through type I interferon signaling.
Through our findings, we have preliminarily elucidated the cells proliferation and acquisition of tumor cytotoxicity mechanism of CIKIL-15 and CIKIL-2. Better understanding of these mechanisms will help to generate novel CIK cells with greater proliferation potential and improved tumor cytolytic function.
PMCID: PMC4134122  PMID: 25108500
CIK cells; Interleukin 2; Interleukin 15; Deep sequencing; Transcriptome
19.  Transcriptional regulation of the p73 gene by Nrf-2 and promoter CpG methylation in human breast cancer 
Oncotarget  2014;5(16):6909-6922.
To understand the transcriptional regulation of p73 by promoter methylation and Nrf-2 in breast carcinogenesis, ChIP assay indicated that Nrf-2 can bind to both promoters and can activate the transcription of TAp73 and ΔΝp73 in MCF-7 cell line, knockdown of Nrf-2 gene resulted in an abrogation of TAp73 and ΔΝp73 expression in the cells transfected with sh-Nrf-2 as well as Nrf-2 knock out mouse model. However, we found Nrf-2 induced ΔΝp73 expression was abolished with 5-aza-dC treatment, thus lead to a down-regulated ΔΝp73 and an up-regulated TAp73 expression in breast cancer cells lines. Consistent with this model, we detected decreased TAp73 and increased ΔNp73 expression in breast cancer tissue, along with increased TAp73 but decreased ΔNp73 expression in corresponding surrounding noncancerous tissues (NCTs) in a breast cancer tissue assay. A significant inverse correlation was found between TAp73 and ΔNp73 expression in the above tissue-array (P = 0.047) and validated in another set consisting of 128 breast cancer tumor tissue (P = 0.034). Taken together, our findings suggest that Nrf-2 and promoter methylation cooperatively govern the transcriptional regulation of p73, and unbalanced expression of TAp73 and ΔNp73 expression plays a critical role in breast cancer development.
PMCID: PMC4196172  PMID: 25071010
breast cancer; TAp73; ΔNp73; Nrf-2; methylation; transcription
20.  Electrically and Optically Readable Light Emitting Memories 
Scientific Reports  2014;4:5121.
Electrochemical metallization memories based on redox-induced resistance switching have been considered as the next-generation electronic storage devices. However, the electronic signals suffer from the interconnect delay and the limited reading speed, which are the major obstacles for memory performance. To solve this problem, here we demonstrate the first attempt of light-emitting memory (LEM) that uses SiO2 as the resistive switching material in tandem with graphene-insulator-semiconductor (GIS) light-emitting diode (LED). By utilizing the excellent properties of graphene, such as high conductivity, high robustness and high transparency, our proposed LEM enables data communication via electronic and optical signals simultaneously. Both the bistable light-emission state and the resistance switching properties can be attributed to the conducting filament mechanism. Moreover, on the analysis of current-voltage characteristics, we further confirm that the electroluminescence signal originates from the carrier tunneling, which is quite different from the standard p-n junction model. We stress here that the newly developed LEM device possesses a simple structure with mature fabrication processes, which integrates advantages of all composed materials and can be extended to many other material systems. It should be able to attract academic interest as well as stimulate industrial application.
PMCID: PMC4044638  PMID: 24894723
21.  MEIOB exhibits single-stranded DNA-binding and exonuclease activities and is essential for meiotic recombination 
Nature communications  2013;4:2788.
Meiotic recombination enables the reciprocal exchange of genetic material between parental homologous chromosomes and ensures faithful chromosome segregation during meiosis in sexually reproducing organisms. This process relies on the complex interaction of DNA repair factors, and many steps remain poorly understood in mammals. Here we report the identification of MEIOB, a meiosis-specific protein, in a proteomics screen for novel meiotic chromatin-associated proteins in mice. MEIOB contains an OB domain with homology to one of the RPA1 OB folds. MEIOB binds to single-stranded DNA and exhibits 3’ to 5’ exonuclease activity. MEIOB forms a complex with RPA and with SPATA22, and these three proteins colocalize in foci that are associated with meiotic chromosomes. Strikingly, chromatin localization and stability of MEIOB depends on SPATA22 and vice versa. Meiob-null mouse mutant exhibits a failure in meiosis and sterility in both sexes. Our results suggest that MEIOB is required for meiotic recombination and chromosomal synapsis.
PMCID: PMC3891831  PMID: 24240703
22.  Hypersensitivity of the hippocampal CA3 region to stress-induced neurodegeneration and amyloidogenesis in a rat model of surgical menopause 
Brain  2013;136(5):1432-1445.
Females who enter menopause prematurely via bilateral ovariectomy (surgical menopause) have a significantly increased risk for cognitive decline and dementia. To help elucidate the mechanisms underlying this phenomenon, we used an animal model of surgical menopause, long-term (10-week) bilateral ovariectomy in female rats. Herein, we demonstrate that long-term oestrogen deprivation dramatically increases sensitivity of the normally resistant hippocampal CA3 region to ischaemic stress, an effect that was gender-specific, as it was not observed in long-term orchiectomized males. Furthermore, the enhanced damage to the CA3 region correlated with a worse cognitive outcome after ischaemic stress. Long-term ovariectomized rats also displayed a robust hyperinduction of Alzheimer’s disease-related proteins in the CA3 region and a switch in amyloid precursor protein processing from non-amyloidogenic to amyloidogenic following ischaemic stress CA3 hypersensitivity also extended to an Alzheimer’s disease-relevant insult, as the CA3 region of long-term ovariectomized rats was profoundly hypersensitive to the neurotoxic effects of amyloid-β1–42, the most amyloidogenic form of the amyloid-β peptide. Additional studies revealed that CA3 region hypersensitivity, Alzheimer’s disease-related protein induction, and amyloidogenesis are mediated by a NADPH oxidase/superoxide/c-Jun N-terminal kinase/c-Jun signalling pathway, involving both transcriptional and post-translational mechanisms. In addition, while 17β-oestradiol replacement at the end of the long-term oestrogen deprivation period could not prevent CA3 hypersensitivity and amyloidogenesis, if 17β-oestradiol was initiated at the time of ovariectomy and maintained throughout the 10-week oestrogen deprivation period, it completely prevented these events, providing support for the ‘critical window’ hypothesis for oestrogen replacement therapy benefit. Collectively, these findings may help explain the increased risk of cognitive decline and dementia observed in women following surgical menopause, and they provide increased support that early 17β-oestradiol replacement is critical in preventing the negative neural effects associated with bilateral ovariectomy.
PMCID: PMC3634196  PMID: 23474850
global cerebral ischaemia; hippocampus; cognition; surgical menopause; Alzheimer’s disease
23.  Entecavir vs lamivudine therapy for naïve patients with spontaneous reactivation of hepatitis B presenting as acute-on-chronic liver failure 
AIM: To investigate the short-term and long-term efficacy of entecavir versus lamivudine in patients with spontaneous reactivation of hepatitis B presenting as acute-on-chronic liver failure (ACLF).
METHODS: This was a single center, prospective cohort study. Eligible, consecutive hospitalized patients received either entecavir 0.5 mg/d or lamivudine 100 mg/d. All patients were given standard comprehensive internal medicine. The primary endpoint was survival rate at day 60, and secondary endpoints were reduction in hepatitis B virus (HBV) DNA and alanine aminotransferase (ALT) levels, and improvement in Child-Turcotte-Pugh (CTP) and model for end-stage liver disease (MELD) scores at day 60 and survival rate at week 52.
RESULTS: One hundred and nineteen eligible subjects were recruited from 176 patients with severe acute exacerbation of chronic hepatitis B: 65 were included in the entecavir group and 54 in the lamivudine group (full analysis set). No significant differences were found in patient baseline clinical parameters. At day 60, entecavir did not improve the probability of survival (P = 0.066), despite resulting in faster virological suppression (P < 0.001), higher rates of virological response (P < 0.05) and greater reductions in the CTP and MELD scores (all P < 0.05) than lamivudine. Intriguingly, at week 52, the probability of survival was higher in the entecavir group than in the lamivudine group [42/65 (64.6%) vs 26/54 (48.1%), respectively; P = 0.038]. The pretreatment MELD score (B, 1.357; 95%Cl: 2.138-7.062; P = 0.000) and virological response at day 30 (B, 1.556; 95%Cl: 1.811-12.411; P =0.002), were found to be good predictors for 52-wk survival.
CONCLUSION: Entecavir significantly reduced HBV DNA levels, decreased the CTP and MELD scores, and thereby improved the long-term survival rate in patients with spontaneous reactivation of hepatitis B presenting as ACLF.
PMCID: PMC4000512  PMID: 24782628
Acute-on-chronic liver failure; Hepatitis B; Entecavir; Lamivudine; Survival
24.  Human Periodontal Ligament Derived Progenitor Cells: Effect of STRO-1 Cell Sorting and Wnt3a Treatment on Cell Behavior 
BioMed Research International  2014;2014:145423.
Objectives. STRO-1 positive periodontal ligament cells (PDLCs) and unsorted PDLCs have demonstrated potential for periodontal regeneration, but the comparison between unsorted cells and the expanded STRO-1 sorted cells has never been reported. Additionally, Wnt3a is involved in cell proliferation thus may benefit in vitro PDLC expansion. The aim was to evaluate the effect of STRO-1 cell sorting and Wnt3a treatment on cell behavior of human PDLCs (hPDLCs). Materials and Methods. STRO-1 positive hPDLCs were sorted and the sorted cells were expanded and compared with their unsorted parental cells. Thereafter, hPDLCs were treated with or without Wnt3a and the cell proliferation, self-renewal, and osteogenic differentiation were evaluated. Results. No differences were measured between the expanded STRO-1-sorted cells and unsorted parental cells in terms of proliferation, CFU, and mineralization capacity. Wnt3a enhanced the proliferation and self-renewal ability of hPDLCs significantly as displayed by higher DNA content values, a shorter cell population doubling time, and higher expression of the self-renewal gene Oct4. Moreover, Wnt3a promoted the expansion of hPDLCs for 5 passages without affecting cell proliferation, CFU, and osteogenic capacity. Conclusions. Expanded STRO-1-sorted hPDLCs showed no superiority compared to their unsorted parental cells. On the other hand, Wnt3a promotes the efficient hPDLC expansion and retains the self-renewal and osteogenic differentiation capacity.
PMCID: PMC4020471  PMID: 24864228
25.  A Three Dimensional Study of Upper Airway in Adult Skeletal Class II Patients with Different Vertical Growth Patterns 
PLoS ONE  2014;9(4):e95544.
The study was performed to compare the 3D pharyngeal airway dimensions in adult skeletal Class II patients with different vertical growth patterns (low, normal, and high angle) and to investigate whether the upper airway dimensions of untreated skeletal Class II adults were affected by vertical skeletal variables.
Cone-beam computed tomography (CBCT) records of 64 untreated adult skeletal Class II patients (34 male and 30 female) were collected to evaluate the pharyngeal airway dimensions. Subjects were divided into three subgroups according to the GoGn-SN angle (low angle, normal angle or high angle). All subgroups were matched for sex. ANOVA and SNK - q tests were used to identify differences within and among groups (p<0.05). Coefficient of product-moment correlation (Pearson correlation coefficient) was used to analyze the association between pharyngeal airway dimensions and vertical growth patterns.
The results showed that pharyngeal airway measurements were statistically significantly less (p<0.05) in high angle group as compared to normal angle or low angle group.
Adult skeletal Class II subjects with vertical growth patterns have significantly narrower pharyngeal airways than those with normal or horizontal growth patterns, confirming an association between pharyngeal airway measurements and a vertical skeletal pattern.
PMCID: PMC3995783  PMID: 24755893

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