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1.  Homocysteine upregulates soluble epoxide hydrolase in vascular endothelium in vitro and in vivo 
Circulation research  2012;110(6):808-817.
Rationale
Hyperhomocysteinemia is a risk factor of atherogenesis. Soluble epoxide hydrolase (sEH) is a major enzyme hydrolyzing epoxyeicosatrienoic acids and attenuates their cardiovascular protective effects. Whether homocysteine (Hcy) regulates sEH and the underlying mechanism remains elusive.
Objective
To elucidate the mechanism by which Hcy regulates sEH expression and endothelial activation in vitro and in vivo.
Methods and Results
Hcy treatment in cultured human endothelial cells dose- and time-dependently upregulated sEH mRNA and protein. Hcy increased the expression of adhesion molecules, which was markedly reversed by inhibiting sEH activity. Hcy-induced sEH upregulation is associated with activation of activating transcription factor 6 (ATF6). Bioinformatics analysis revealed a putative ATF6-binding motif in the promoter region of the sEH gene, which was found being a methylation site. Site-directed mutagenesis and chromatin immunoprecipitation assays demonstrated that Hcy treatment or ATF6 overexpression promoted ATF6 binding to the promoter of sEH and increased its activity. Result of methylation-specific PCR revealed that the ATF6 binding site on the sEH promoter was partially methylated and was demethylated with Hcy. SiRNA knockdown of ATF6α and/or SP1 blocked, and ATF6 overexpression and DNA methyltransferase inhibitor mimicked, the effect of homocysteine on sEH upregulation. In vivo, immunofluorescence assay revealed elevated expression of sEH and adhesion molecules in the aortic intima of mice with mild hyperhomocysteinemia, which was attenuated by sEH deletion or inhibition.
Conclusion
ATF6 activation and DNA demethylation may coordinately contribute to Hcy-induced sEH expression and endothelial activation. Inhibition of sEH may be a therapeutic approach for treating Hcy-induced cardiovascular diseases.
doi:10.1161/CIRCRESAHA.111.259325
PMCID: PMC3514454  PMID: 22354938
sEH; homocysteine; ATF6; demethylation; endothelial cells
2.  Quantitative assessment of the associations between XRCC1 polymorphisms and bladder cancer risk 
Background
The XRCC1 polymorphisms have been implicated in bladder cancer risk, but individually published studies show inconsistent results. The aim of our study was to clarify the effects of XRCC1 variants on bladder cancer risk.
Methods
A systematic literature search up to September 13, 2012 was carried out in PubMed, EMBASE and Wanfang databases, and the references of retrieved articles were screened. Crude odds ratios with 95% confidence intervals were used to assess the associations between XRCC1 Arg194Trp and Arg399Gln polymorphisms and bladder cancer risk. Heterogeneity and publication bias were also evaluated.
Results
A total of 14 and 18 studies were eligible for meta-analyses of Arg194Trp and Arg399Gln, respectively. Regrouping was adopted in accordance with the most probable appropriate genetic models. No obvious heterogeneity between studies was found. For overall bladder cancer, the pooled odds ratios for Arg194Trp and Arg399Gln were 1.69 (95% confidence interval: 1.25 to 2.28; P = 0.001) and 1.10 (95% confidence interval: 1.03 to 1.19; P = 0.008), respectively. After excluding the studies that were not in Hardy–Weinberg equilibrium, the estimated pooled odds ratio still did not change at all.
Conclusions
The meta-analysis results suggest that XRCC1 Arg194Trp and Arg399Gln polymorphisms may be associated with elevated bladder cancer risk.
doi:10.1186/1477-7819-11-58
PMCID: PMC3601005  PMID: 23496911
XRCC1; Polymorphism; Bladder cancer; Meta-analysis
3.  Diabetes Mellitus and Risk of Bladder Cancer: A Meta-Analysis of Cohort Studies 
PLoS ONE  2013;8(3):e58079.
Objective
Diabetes is associated with increased risk of cancer at several sites, but its association with risk of bladder cancer is still controversial. We examined this association by conducting a systematic review and meta-analysis of cohort studies.
Methods
Studies were identified by searching PubMed, EMBASE, Scopus, Web of Science, Cochrane register, and Chinese National Knowledge Infrastructure (CNKI) databases through April 29, 2012. Summary relative risks (SRRs) with their corresponding 95% confidence intervals (CIs) were calculated using a random-effects model.
Results
A total of fifteen cohort studies were included in this meta-analysis. Analysis of all studies showed that diabetes was associated with a borderline statistically significant increased risk of bladder cancer (RR 1.11, 95% CI 1.00–1.23; p<0.001 for heterogeneity; I2 = 84%). When restricting the analysis to studies that had adjusted for cigarette smoking (n = 6) or more than three confounders (n = 7), the RRs were 1.32 (95% CI 1.18–1.49) and 1.20 (95% CI 1.02–1.42), respectively. There was no significant publication bias (p = 0.62 for Egger’s regression asymmetry test).
Conclusions
Our findings support that diabetes was associated with an increased risk of bladder cancer. More future studies are warranted to get a better understanding of the association and to provide convincing evidence for clinical practice in bladder cancer prevention.
doi:10.1371/journal.pone.0058079
PMCID: PMC3589481  PMID: 23472134
4.  Association of prostate cancer risk with SNPs in regions containing androgen receptor binding sites captured by ChIP-on-chip analyses 
The Prostate  2011;72(4):376-385.
Background
Genome-wide association studies (GWAS) have identified approximately three dozen single nucleotide polymorphisms (SNPs) consistently associated with prostate cancer (PCa) risk. Despite the reproducibility of these associations, the molecular mechanism for most of these SNPs has not been well elaborated as most lie within non-coding regions of the genome. Androgens play a key role in prostate carcinogenesis. Recently, using ChIP-on-chip technology, 22,447 androgen receptor (AR) binding sites have been mapped throughout the genome, greatly expanding the genomic regions potentially involved in androgen-mediated activity.
Methodology/Principal findings
To test the hypothesis that sequence variants in AR binding sites are associated with PCa risk, we performed a systematic evaluation among two existing PCa GWAS cohorts; the Johns Hopkins Hospital and the Cancer Genetic Markers of Susceptibility (CGEMS) study population. We demonstrate that regions containing AR binding sites are significantly enriched for PCa risk-associated SNPs, i.e. more than expected by chance alone. In addition, compared with the entire genome, these newly observed risk-associated SNPs in these regions are significantly more likely to overlap with established PCa risk-associated SNPs from previous GWAS. These results are consistent with our previous finding from a bioinformatics analysis that one-third of the 33 known PCa risk-associated SNPs discovered by GWAS are located in regions of the genome containing AR binding sites.
Conclusions/Significance
The results to date provide novel statistical evidence suggesting an androgen-mediated mechanism by which some PCa associated SNPs act to influence PCa risk. However, these results are hypothesis generating and ultimately warrant testing through in-depth molecular analyses.
doi:10.1002/pros.21439
PMCID: PMC3366362  PMID: 21671247
AR; prostate cancer; GWAS; pathway association study
5.  Hydrogen Sulfide Protects HUVECs against Hydrogen Peroxide Induced Mitochondrial Dysfunction and Oxidative Stress 
PLoS ONE  2013;8(2):e53147.
Background
Hydrogen sulfide (H2S) has been shown to have cytoprotective effects in models of hypertension, ischemia/reperfusion and Alzheimer's disease. However, little is known about its effects or mechanisms of action in atherosclerosis. Therefore, in the current study we evaluated the pharmacological effects of H2S on antioxidant defenses and mitochondria protection against hydrogen peroxide (H2O2) induced endothelial cells damage.
Methodology and Principal Findings
H2S, at non-cytotoxic levels, exerts a concentration dependent protective effect in human umbilical vein endothelial cells (HUVECs) exposed to H2O2. Analysis of ATP synthesis, mitochondrial membrane potential (ΔΨm) and cytochrome c release from mitochondria indicated that mitochondrial function was preserved by pretreatment with H2S. In contrast, in H2O2 exposed endothelial cells mitochondria appeared swollen or ruptured. In additional experiments, H2S was also found to preserve the activities and protein expressions levels of the antioxidants enzymes, superoxide dismutase, catalase, glutathione peroxidase and glutathione-S-transferase in H2O2 exposed cells. ROS and lipid peroxidation, as assessed by measuring H2DCFDA, dihydroethidium (DHE), diphenyl-l-pyrenylphosphine (DPPP) and malonaldehyde (MDA) levels, were also inhibited by H2S treatment. Interestingly, in the current model, D, L-propargylglycine (PAG), a selective inhibitor of cystathionine γ-lyase (CSE), abolished the protective effects of H2S donors.
Innovation
This study is the first to show that H2S can inhibit H2O2 mediated mitochondrial dysfunction in human endothelial cells by preserving antioxidant defences.
Significance
H2S may protect against atherosclerosis by preventing H2O2 induced injury to endothelial cells. These effects appear to be mediated via the preservation of mitochondrial function and by reducing the deleterious effects of oxidative stress.
doi:10.1371/journal.pone.0053147
PMCID: PMC3564806  PMID: 23393548
6.  Mechanistic Target of Rapamycin (Mtor) Is Essential for Murine Embryonic Heart Development and Growth 
PLoS ONE  2013;8(1):e54221.
Mechanistic target of rapamycin (Mtor) is required for embryonic inner cell mass proliferation during early development. However, Mtor expression levels are very low in the mouse heart during embryogenesis. To determine if Mtor plays a role during mouse cardiac development, cardiomyocyte specific Mtor deletion was achieved using α myosin heavy chain (α-MHC) driven Cre recombinase. Initial mosaic expression of Cre between embryonic day (E) 10.5 and E11.5 eliminated a subset of cardiomyocytes with high Cre activity by apoptosis and reduced overall cardiac proliferative capacity. The remaining cardiomyocytes proliferated and expanded normally. However loss of 50% of cardiomyocytes defined a threshold that impairs the ability of the embryonic heart to sustain the embryo’s circulatory requirements. As a result 92% of embryos with cardiomyocyte Mtor deficiency died by the end of gestation. Thus Mtor is required for survival and proliferation of cardiomyocytes in the developing heart.
doi:10.1371/journal.pone.0054221
PMCID: PMC3544830  PMID: 23342106
7.  Estimation of benchmark dose for micronucleus occurrence in Chinese vinyl chloride-exposed workers☆ 
In this study, we estimated the possibility of using benchmark dose (BMD) to assess the dose–response relationship between vinyl chloride monomer (VCM) exposure and chromosome damage. A group of 317 workers occupationally exposed to vinyl chloride monomer and 166 normal, unexposed control in Shan-dong Province northern China were examined for chromosomal damage in peripheral blood lymphocytes (PBL) using the cytokinesis-blocked micronucleus (CB-MN) assay of DNA damage. The exposed group (3.47 ± 2.65)‰ showed higher micronucleus frequency than the control (1.60 ± 1.30)‰ (P < 0.01). Occupational exposure level based on micronucleus occurrence in all individuals was analyzed with benchmark dose (BMD) methods. The benchmark dose lower limit of a one-sided 95% confidence interval (BMDL) for 10% excess risk was also determined. Results showed a dose–response relationship between cumulative exposure and MN frequency, and a BMDL of 0.54 mg/m3 and 0.23 mg/m3 for males and females, respectively. Female workers were more susceptible to MN damage than male workers.
doi:10.1016/j.ijheh.2012.02.008
PMCID: PMC3404251  PMID: 22425610
Vinyl chloride monomer; Chromosomal damage; Benchmark dose; Micronucleus
8.  Hydrogen Sulfide as an Endogenous Modulator in Mitochondria and Mitochondria Dysfunction 
Hydrogen sulfide (H2S) has historically been considered to be a toxic gas, an environmental and occupational hazard. However, with the discovery of its presence and enzymatic production through precursors of L-cysteine and homocysteine in mammalian tissues, H2S has recently received much interest as a physiological signaling molecule. H2S is a gaseous messenger molecule that has been implicated in various physiological and pathological processes in mammals, including vascular relaxation, angiogenesis, and the function of ion channels, ischemia/reperfusion (I/R), and heart injury. H2S is an endogenous neuromodulator and present studies show that physiological concentrations of H2S enhance NMDA receptor-mediated responses and aid in the induction of hippocampal long-term potentiation. Moreover, in the field of neuronal protection, physiological concentrations of H2S in mitochondria have many favorable effects on cytoprotection.
doi:10.1155/2012/878052
PMCID: PMC3523162  PMID: 23304257
9.  Development of a gene therapy strategy to target hepatocellular carcinoma based inhibition of protein phosphatase 2A using the α-fetoprotein promoter enhancer and pgk promoter: an in vitro and in vivo study 
BMC Cancer  2012;12:547.
Background
Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related deaths worldwide. Current therapies are insufficient, making HCC an intractable disease. Our previous studies confirmed that inhibition of protein phosphatase 2A (PP2A) may provide a promising therapeutic strategy for cancer. Unfortunately, constitutive expression of PP2A in normal tissues limits the application of PP2A inhibition. Thus, a HCC-specific gene delivery system should be developed. The α-fetoprotein (AFP) promoter is commonly used in HCC-specific gene therapy strategies; however, the utility of this approach is limited due to the weak activity of the AFP promoter. It has been shown that linking the AFP enhancer with the promoter of the non-tissue-specific, human housekeeping phosphoglycerate kinase (pgk) gene can generate a strong and HCC-selective promoter.
Methods
We constructed a HCC-specific gene therapy system to target PP2A using the AFP enhancer/pgk promoter, and evaluated the efficiency and specificity of this system both in vitro and in vivo.
Results
AFP enhancer/pgk promoter-driven expression of the dominant negative form of the PP2A catalytic subunit α (DN-PP2Acα) exerted cytotoxic effects against an AFP-positive human hepatoma cell lines (HepG2 and Hep3B), but did not affect AFP-negative human hepatoma cells (SK-HEP-1) or normal human liver cells (L-02). Moreover, AFP enhancer/pgk promoter driven expression of DN-PP2Acα inhibited the growth of AFP-positive HepG2 tumors in nude mice bearing solid tumor xenografts, but did not affect AFP-negative SK-HEP-1 tumors.
Conclusions
The novel approach of AFP enhancer/pgk promoter-driven expression of DN-PP2Acα may provide a useful cancer gene therapy strategy to selectively target HCC.
doi:10.1186/1471-2407-12-547
PMCID: PMC3574000  PMID: 23173703
Hepatocellular carcinoma; AFP; Pgk; PP2A
10.  PAI-1 promoter 4G/5G polymorphism (rs1799768) contributes to tumor susceptibility: Evidence from meta-analysis 
Plasminogen activator inhibitor-1 (PAI-1), belonging to the urokinase plasminogen activation (uPA) system, is involved in cancer development and progression. The PAI-1 promoter 4G/5G polymorphism was shown to contribute to genetic susceptibility to cancer, although the results were inconsistent. To assess this relationship more precisely, a meta-analysis was performed. The electronic databases PubMed, Scopus, Web of Science and Chinese National Knowledge Infrastructure (CNKI) were searched; data were extracted and analyzed independently by two reviewers. Ultimately, 21 eligible case-control studies with a total of 8,415 cancer cases and 9,208 controls were included. The overall odds ratio (OR) with its 95% confidence interval (CI) showed a statistically significant association between the PAI-1 promoter 4G/5G polymorphism and cancer risk (4G/4G vs. 5G/5G: OR=1.25, 95% CI=1.07–1.47, Pheterogeneity=0.001; 4G/4G vs. 4G/5G+5G/5G: OR=1.10, 95% CI=1.03–1.17, Pheterogeneity=0.194; 4G/4G+4G/5G vs. 5G/5G: OR=1.17, 95% CI=1.01–1.35, Pheterogeneity=0.041). In further subgroup analyses, the increased risk of cancer was observed in a subgroup of Caucasians with regards to endometrial cancer. Our meta-analysis suggests that the PAI-1 4G/5G polymorphism most likely contributes to susceptibility to cancer, particularly in Caucasians. Furthermore, the 4G allele may be associated with an increased risk of endometrial cancer.
doi:10.3892/etm.2012.734
PMCID: PMC3494103  PMID: 23226787
plasminogen activator inhibitor-1; carcinoma; genetic polymorphism; susceptibility; meta-analysis
11.  PI3K p110α Isoform-Dependent Rho GTPase Rac1 Activation Mediates H2S-Promoted Endothelial Cell Migration via Actin Cytoskeleton Reorganization 
PLoS ONE  2012;7(9):e44590.
Hydrogen sulfide (H2S) is now considered as the third gaseotransmitter, however, the signaling pathways that modulate the biomedical effect of H2S on endothelial cells are poorly defined. In the present study, we found in human endothelial cells that H2S increased cell migration rates and induced a marked reorganization of the actin cytoskeleton, which was prevented by depletion of Rac1. Pharmacologic inhibiting vascular endothelial growth factor receptor (VEGFR) and phosphoinositide 3-kinase (PI3K) both blunted the activation of Rac1 and the promotion of cell migration induced by H2S. Moreover, H2S-induced Rac1 activation was selectively dependent on the presence of the PI3K p110α isoform. Activated Rac1 by H2S thus in turn resulted in the phosphorylation of the F-actin polymerization modulator, cofilin. Additionally, inhibiting of extracellular signal-regulated kinase (ERK) decreased the augmented cell migration rate by H2S, but had no effect on Rac1 activation. These results indicate that Rac1 conveys the H2S signal to microfilaments inducing rearrangements of actin cytoskeleton that regulates cell migration. VEGFR-PI3K was found to be upstream pathway of Rac1, while cofilin acted as a downstream effector of Rac1. ERK was also shown to be involved in the action of H2S on endothelial cell migration, but independently of Rac1.
doi:10.1371/journal.pone.0044590
PMCID: PMC3436785  PMID: 22970259
12.  Is the lag screw sliding effective in the intramedullary nailing in A1 and A2 AO-OTA intertrochanteric fractures? A prospective study of Sliding and None-sliding lag screw in Gamma-III nail 
Object
To compare the Sliding with Non-sliding lag screw of a gamma nail in the treatment of A1 and A2 AO-OTA intertrochanteric fractures.
Materials and methods
80 patients were prospectively collected. In each group, AO/OTA 31-A were classified into group A. AO/OTA 31-A2.1 was classified as group B. We classified the A2.2 and A2.3 as group C. According to the set-screw locking formation of Gamma-III, the cases were randomly allocated to Sliding subgroup and Non-sliding subgroup in A, B and C groups. Follow-ups were performed 1, 3, 6 and 12 months postoperatively.
Results
In the Sliding group, the bone healing rate 3, 6, 12 months postoperatively reached 85.00%, 97.50%, 100% in group A, B and C. Meanwhile, in Non-sliding group, postoperatively, bone healing rate were 90.00%, 95.00% and 97.50% in group A, B and C, respectively. Both differences were not significant. Lower limb discrepancy between Sliding and Non-sliding pattern was significantly different in group C which represent fracture types of AO/OTA 31-A2.2 and A2.3 (0.573 ± 0.019 mm in Non-sliding group, 0.955 mm ± 0.024 mm in Sliding group, P < 0.001 ). Difference of sliding distance among the three groups was significant among group A, B and C: 0.48 mm ± 0.04 mm, 0.62 mm ± 0.07 mm and 0.92 mm ± 0.04 mm (P < 0.001). Differences in average healing time and Harris scores also presented no significance in the three groups.
Conclusions
As a result, we can conclude that the sliding distance is minimal in Gamma nails and it is related to the comminuted extent of the intertrochanteric area in A1 and A2 AO-OTA intertrochanteric fractures. For treating these kinds of fractures, the sliding of the lag screw of an Gamma nail does not improve any clinical results and in certain cases, such as highly comminuted A1 and A2 fractures, can therefore even benefit from a locked lag screw by tightening the set-screw.
doi:10.1186/1757-7241-20-60
PMCID: PMC3518244  PMID: 22938031
Intertrochanteric fractures; A1 and A2 AO-OTA; Gamma nail; Lag screw sliding
13.  Impaired Expression of Uncoupling Protein 2 (UCP2) Causes Defective Post-ischemic Angiogenesis in Mice Deficient in AMP-activated Protein Kinase α Subunits 
Objective
The aim of the present study was to determine whether mitochondrial uncoupling protein (UCP)-2 is required for AMPK-dependent angiogenesis in ischemia in vivo.
Methods and Results
Angiogenesis was assayed by monitoring endothelial tube formation (a surrogate for angiogenesis) in human umbilical vein endothelial cells (HUVECs), isolated mouse aortic endothelial cells (MAECs), and pulmomary microvascular endothelial cells (PMECs), or in ischemic thigh adductor muscles from wild-type (WT) mice or mice deficient in either AMPKα1 or AMPKα2. AMPK inhibition with pharmacological inhibitor (compound C) or genetic means (transfection of AMPKα-specific siRNA) significantly lowered the tube formation in HUVECs. Consistently, compared with WT mice, tube formation in MAECs isolated from either AMPKα1−/− or AMPKα2−/− mice, which exhibited oxidative stress and reduced expression of UCP2, were significantly impaired. In addition, adenoviral overexpression of UCP2, but not adenoviruses encoding green florescence protein (GFP), normalized tube formation in MAECs from either AMPKα1−/− or AMPKα2−/− mice. Similarly, supplementation with sodium nitroprusside (SNP), a nitric oxide (NO) donor, restored tube formation. Furthermore, ischemia significantly increased angiogenesis, serine 1177 phosphorylation of endothelial NO synthase (eNOS), and UCP2 in ischemic thigh adductor muscles from WT mice, but not from either AMPKα1−/− or AMPKα2−/− mice.
Conclusion
We conclude that AMPK-dependent UCP2 expression in endothelial cells promotes angiogenesis in vivo.
doi:10.1161/ATVBAHA.111.227991
PMCID: PMC3158995  PMID: 21597006
AMPK; uncoupling protein-2; nitric oxide; angiogenesis
14.  Increased risk of cancer in patients with type 2 diabetes mellitus: A retrospective cohort study in China 
BMC Public Health  2012;12:567.
Background
Previous studies indicated that type 2 diabetes mellitus (T2DM) might be associated with the risk of cancer. The aim of this study was to investigate the association between T2DM and the risk of developing common cancers in a Chinese population.
Methods
A population-based retrospective cohort study was carried out in the Nan-Hu district of Jiaxing city, Zhejiang province, China. The incidence of cancer cases among type 2 diabetic patients were identified through record-linkage of the Diabetic Surveillance and Registry Database with the Cancer Database from January 2002 to June 2008. The standardized incidence ratio (SIR) and 95% confidence interval (CI) were estimated for the risk of cancer among the patients with type 2 diabetes.
Results
The overall incidence of cancer was 1083.6 per 105 subjects in male T2DM patients and 870.2 per 105 in females. Increased risk of developing cancer was found in both male and female T2DM patients with an SIR of 1.331 (95% CI = 1.143-1.518) and 1.737 (1.478-1.997), respectively. As for cancer subtypes, both male and female T2DM patients had a significantly increased risk of pancreatic cancer with the SIRs of 2.973 (1.73-4.21) and 2.687 (1.445-3.928), respectively. Elevated risk of liver and kidney cancers was only found in male T2DM patients with SIRs of 1.538 (1.005-2.072) and 4.091 (1.418-6.764), respectively. Increased risks of developing breast cancer [2.209 (1.487-2.93)] and leukemia SIR: [4.167 (1.584- 6.749) ] were found in female patients.
Conclusions
These findings indicated that patients with T2DM have an increased risk of developing cancer. Additional cancer screening should be employed in the management of patients with T2DM.
doi:10.1186/1471-2458-12-567
PMCID: PMC3487805  PMID: 22839452
15.  8,9-Epoxyeicosatrienoic Acid Inhibits Antibody Production of B Lymphocytes in Mice 
PLoS ONE  2012;7(7):e40258.
Epoxyeicosatrienoic acids (EETs), synthesized from arachidonic acid by cytochrome P450 epoxygenases, are converted to dihydroxyeicosatrienoic acids by soluble epoxide hydrolase. EETs exert anti-inflammatory effects. However, the effect of EETs on humoral immunity is poorly understood. The present study is to investigate the potential role of EETs on B cell function and mechanisms. We examined the role of EETs on antibody production of splenic B cells from C57BL/6 and apolipoprotein E-deficient (ApoE−/−) mice by means of ELISA. Of the 4 EET regioisomers, 8,9-EET decreased basal and activation-induced B cell antibody secretion. As well, 8,9-EET significantly inhibited B-cell proliferation and survival, plasma cell differentiation and class-switch recombination. Western blot analysis revealed that lipopolysaccharide-induced nuclear translocation of NF-κB could be attenuated by 8,9-EET. Furthermore, germinal center formation was impaired by 8,9-EET in mice in vivo. 8,9-EET may inhibit B-cell function in vitro and in vivo, which suggests a new therapeutic strategy for diseases with excess B cell activation.
doi:10.1371/journal.pone.0040258
PMCID: PMC3389024  PMID: 22802958
16.  Inhibition of Soluble Epoxide Hydrolase Attenuates High-Fat-Diet–Induced Hepatic Steatosis by Reduced Systemic Inflammatory Status in Mice 
PLoS ONE  2012;7(6):e39165.
Non-alcoholic fatty liver disease is associated with obesity and considered an inflammatory disease. Soluble epoxide hydrolase (sEH) is a major enzyme hydrolyzing epoxyeicosatrienoic acids and attenuates their cardiovascular protective and anti-inflammatory effects. We examined whether sEH inhibition can protect against high-fat (HF)-diet–induced fatty liver in mice and the underlying mechanism. Compared with wild-type littermates, sEH-null mice showed lower diet-induced lipid accumulation in liver, as seen by Oil-red O staining and triglycerides levels. We studied the effect of sEH inhibition on diet-induced fatty liver by feeding C57BL/6 mice an HF diet for 8 weeks (short-term) or 16 weeks (long-term) and administering t-AUCB, a selective sEH inhibitor. sEH inhibition had no effect on the HF-diet–increased body and adipose tissue weight or impaired glucose tolerance but alleviated the diet-induced hepatic steatosis. Adenovirus-mediated overexpression of sEH in liver increased the level of triglycerides in liver and the hepatic inflammatory response. Surprisingly, the induced expression of sEH in liver occurred only with the long-term but not short-term HF diet, which suggests a secondary effect of HF diet on regulating sEH expression. Furthermore, sEH inhibition attenuated the HF-diet–induced increase in plasma levels of proinflammatory cytokines and their mRNA upregulation in adipose tissue, which was accompanied by increased macrophage infiltration. Therefore, sEH inhibition could alleviate HF-diet–induced hepatic steatosis, which might involve its anti-inflammatory effect in adipose tissue and direct inhibition in liver. sEH may be a therapeutic target for HF-diet–induced hepatic steatosis in inhibiting systemic inflammation.
doi:10.1371/journal.pone.0039165
PMCID: PMC3375303  PMID: 22720061
17.  Modeling Neuronal Current MRI Signal with Human Neuron 
Up to date, no consensus has been achieved regarding the possibility of detecting neuronal currents by MRI (ncMRI) in human brain. To evaluate the detectability of ncMRI, an effective way is to simulate ncMRI signal with the realistic neuronal geometry and electrophysiological processes. Unfortunately, previous realistic ncMRI models are based on rat and monkey neurons. The species difference in neuronal morphology and physiology would prevent these models from simulating the ncMRI signal accurately in human subjects. The aim of the present study is to bridge this gap by establishing a realistic ncMRI model specifically for human cerebral cortex. In this model, the ncMRI signal was simulated using anatomically reconstructed human pyramidal neurons and their biophysical properties. The modeling results showed that the amplitude of ncMRI signal significantly depends on the density of synchronously firing neurons and imaging conditions such as position of imaging voxel, direction of main magnetic field (B0) relative to the cortical surface and echo time. The results indicated that physiologically-evoked ncMRI signal is too weak to be detected (magnitude/phase change ≤ -1.4×10−6/0.02°), but the phase signal induced by spontaneous activity may reach a detectable level (up to 0.2°) in favorable conditions.
doi:10.1002/mrm.22764
PMCID: PMC3097305  PMID: 21254209
neuronal current; MRI; human; realistic
18.  Laparoscopic distal pancreatectomy is as safe and feasible as open procedure: A meta-analysis 
AIM: To evaluate the feasibility and safety of laparoscopic distal pancreatectomy (LDP) compared with open distal pancreatectomy (ODP).
METHODS: Meta-analysis was performed using the databases, including PubMed, the Cochrane Central Register of Controlled Trials, Web of Science and BIOSIS Previews. Articles should contain quantitative data of the comparison of LDP and ODP. Each article was reviewed by two authors. Indices of operative time, spleen-preserving rate, time to fluid intake, ratio of malignant tumors, postoperative hospital stay, incidence rate of pancreatic fistula and overall morbidity rate were analyzed.
RESULTS: Nine articles with 1341 patients who underwent pancreatectomy met the inclusion criteria. LDP was performed in 501 (37.4%) patients, while ODP was performed in 840 (62.6%) patients. There were significant differences in the operative time, time to fluid intake, postoperative hospital stay and spleen-preserving rate between LDP and ODP. There was no difference between the two groups in pancreatic fistula rate [random effects model, risk ratio (RR) 0.996 (0.663, 1.494), P = 0.983, I2 = 28.4%] and overall morbidity rate [random effects model, RR 0.81 (0.596, 1.101), P = 0.178, I2 = 55.6%].
CONCLUSION: LDP has the advantages of shorter hospital stay and operative time, more rapid recovery and higher spleen-preserving rate as compared with ODP.
doi:10.3748/wjg.v18.i16.1959
PMCID: PMC3337573  PMID: 22563178
Laparoscopy; Distal pancreatectomy; Pancreatic fistula; Spleen-preserving; Morbidity
19.  Prognostic significance of MyD88 expression by human epithelial ovarian carcinoma cells 
Background
MyD88 is an adaptor protein for TLR-4 signaling known to mediate paclitaxel resistance in epithelial ovarian carcinoma (EOC). This study examined the clinical significance of MyD88 expression in EOC.
Methods
MyD88 and TLR-4 expression were examined by immunocytochemistry in 109 specimens of ovarian tissues, comprising EOC (N = 83), borderline tumors (N = 9), benign cysts (N = 9) and normal ovarian tissue (N = 8), and clinical data collected by a retrospective chart review. The correlations between MyD88 expression and clinicopathological factors and outcomes were analyzed.
Results
TLR-4 expression was detected frequently in all the ovarian tissues. Distinct MyD88 expression was showed in EOC (64 of 83, 77.1 %), in borderline tumors (5 of 9, 55.6 %) and in benign cysts (3 of 9, 33.3 %), and normal ovarian tissue showed no MyD88 expression. Positive MyD88 expression significantly correlated with shorter disease-free and overall survival for EOC (P < 0.0001 and P = 0.0031), and high MyD88 expression was significantly correlated with tumor metastasis (P = 0.0012) for EOC. Univariate and multivariate analyses revealed that MyD88 expression was an independent prognostic factor for disease-free survival and overall survival for EOC.
Conclusion
Our data indicate that MyD88 expression is a significantly poor prognostic factor for EOC. A better understanding of the role of MyD88 expression in disease progression and outcome may be helpful for development of novel chemotherapies for patients with EOC.
doi:10.1186/1479-5876-10-77
PMCID: PMC3438113  PMID: 22533866
Ovarian cancer; Myeloid differentiation factor 88; Toll-like receptor 4; Prognostic factors; Metastasis
21.  Absence of Association between N-Acetyltransferase 2 Acetylator Status and Colorectal Cancer Susceptibility: Based on Evidence from 40 Studies 
PLoS ONE  2012;7(3):e32425.
Background and Objectives
N-Acetyltransferase (NAT) 2 is an important enzyme involved in the metabolism of different xenobiotics, including potential carcinogens, whose phenotypes were reported to be related to individual susceptibility to colorectal cancer (CRC). However, the results remain conflicting. To assess the relationship between NAT2 phenotypes and CRC risk, we performed this meta-analysis.
Methods
A comprehensive literature search was conducted to identify all case-control or cohort studies of NAT2 acetylator status on the susceptibility of CRC by searching of PubMed and EMBASE, up to May 20, 2011. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the association.
Results
A total of over 40,000 subjects from 40 published literatures were identified by searching the databases. No significantly elevated CRC risk in individuals with NAT2 slow acetylators compared with fast acetylators was found when all studies pooled (OR = 0.95, 95% CI: 0.87–1.04, I2 = 52.6%). While three studies contributed to the source of heterogeneity were removed, there was still null result observed (OR = 0.96, 95% CI: 0.90–1.03, P = 0.17 for heterogeneity, I2 = 17.8%). In addition, we failed to detect any associations in the stratified analyses by race, sex, source of controls, smoking status, genotyping methods or tumor localization. No publication bias was observed in this study.
Conclusions
This meta-analysis suggests that the NAT2 phenotypes may not be associated with colorectal cancer development.
doi:10.1371/journal.pone.0032425
PMCID: PMC3293792  PMID: 22403658
22.  Inherited genetic markers discovered to date are able to identify a significant number of men at considerably elevated risk for prostate cancer 
The Prostate  2010;71(4):421-430.
BACKGROUND
Prostate cancer (PCa) risk-associated single nucleotide polymorphisms (SNPs) are continuously being discovered. Their ability to identify men at high risk and the impact of increasing numbers of SNPs on predictive performance are not well understood.
METHODS
Absolute risk for PCa was estimated in a population-based case-control study in Sweden (2,899 cases and 1,722 controls) using family history and three sets of sequentially discovered PCa risk-associated SNPs. Their performance in predicting PCa was assessed by positive predictive values (PPV) and sensitivity.
RESULTS
SNPs and family history were able to differentiate individual risk for PCa and identify men at higher risk; ~18% and ~8% of men in the study had 20-year (55–74 years) absolute risks that were two-fold (0.24) or three-fold (0.36) greater than the population median risk (0.12), respectively. When predictive performances were compared at absolute risk cutoffs of 0.12, 0.24 or 0.36, PPV increased considerably (~20%, ~30% and ~37%, respectively) while sensitivity decreased considerably (~55%, ~20% and ~10%, respectively). In contrast, when increasing numbers of SNPs (5, 11 and 28 SNPs) were used in risk prediction, PPV approached a constant value while sensitivity increased steadily.
CONCLUSIONS
SNPs discovered to date are suitable for risk prediction while additional SNPs discovered in the future may identify more subjects at higher risk. Men identified as high-risk by SNP-based testing may be targeted for PCa screening or chemoprevention. The clinical impact on improving the effectiveness of these interventions can be and should be assessed.
doi:10.1002/pros.21256
PMCID: PMC3025084  PMID: 20878950
Absolute risk; SNPs; association; screening; chemoprevention
23.  Effects of S-Propargyl-Cysteine (SPRC) in Caerulein-Induced Acute Pancreatitis in Mice 
PLoS ONE  2012;7(3):e32574.
Hydrogen sulfide (H2S), a novel gaseous messenger, is synthesized endogenously from L-cysteine by two pyridoxal-5′-phosphate-dependent enzymes, cystathionine β-synthase (CBS) and cystathionine γ-lyase (CSE). S-propargyl-cysteine (SPRC) is a slow H2S releasing drug that provides cysteine, a substrate of CSE. The present study was aimed to investigate the effects of SPRC in an in vivo model of acute pancreatitis (AP) in mice. AP was induced in mice by hourly caerulein injections (50 µg/kg) for 10 hours. Mice were treated with SPRC (10 mg/kg) or vehicle (distilled water). SPRC was administered either 12 h before or 3 h before the induction of pancreatitis. Mice were sacrificed 1 h after the last caerulein injection. Blood, pancreas and lung tissues were collected and processed to measure the plasma amylase, plasma H2S, myeloperoxidase (MPO) activities and cytokine levels in pancreas and lung. The results revealed that significant reduction of inflammation, both in pancreas and lung was associated with SPRC given 3 h prior to the induction of AP. Furthermore, the beneficial effects of SPRC were associated with reduction of pancreatic and pulmonary pro-inflammatory cytokines and increase of anti-inflammatory cytokine. SPRC administered 12 h before AP induction did not cause significant improvement in pancreatic and lung inflammation. Plasma H2S concentration showed significant difference in H2S levels between control, vehicle and SPRC (administered 3 h before AP) treatment groups. In conclusion, these data provide evidence for protective effects of SPRC in AP possibly by virtue of its slow release of endogenous H2S.
doi:10.1371/journal.pone.0032574
PMCID: PMC3291555  PMID: 22396778
24.  A novel mechanism of γ/δ T-lymphocyte and endothelial activation by shear stress -- the role of ecto-ATP synthase β chain 
Circulation research  2010;108(4):410-417.
Rationale
Endothelial cells (ECs) have distinct mechanotransduction mechanisms responding to laminar versus disturbed flow patterns. Endothelial dysfunction, affected by imposed flow, is one of the earliest events leading to atherogenesis. The involvement of γ/δ T lymphocytes in endothelial dysfunction under flow is largely unknown.
Objective
To investigate whether shear stress regulates membrane translocation of ATP synthase β chain (ATPSβ) in ECs, leading to the increased γ/δ T-lymphocyte adhesion and the related functions.
Method and Results
We applied different flow patterns to cultured ECs. Laminar flow decreased the level of membrane-bound ATPSβ (ecto-ATPSβ) and depleted membrane cholesterol, whereas oscillatory flow increased the level of ecto-ATPSβ and membrane cholesterol. Incubating ECs with cholesterol or depleting cellular cholesterol with β-cyclodextrin mimicked the effect of oscillatory or laminar flow, respectively. Knockdown caveolin-1 by siRNA prevented ATPSβ translocation in response to laminar flow. Importantly, oscillatory flow or cholesterol treatment elevated the number of γ/δ T cells binding to ECs, which was blocked by anti-ATPSβ antibody. Furthermore, the incubation of γ/δ T cells with ECs increased TNFα and IFNγ secretion from T cells and VCAM-1 expression in ECs. In vivo, γ/δ T-cell adhesion and ATPSβ membrane translocation was elevated in the aortic inner curvature and disturbed flow areas in partially ligated carotid arteries of ApoE−/− mice fed a high-fat diet.
Conclusion
This study provides evidence that disturbed flow and hypercholesterolemia synergistically promote γ/δ T-lymphocyte activation by the membrane translocation of ATPSβ in ECs and in vivo in mice, which is a novel mechanism of endothelial activation.
doi:10.1161/CIRCRESAHA.110.230151
PMCID: PMC3053136  PMID: 21193741
Endothelial dysfunction; T lymphocyte; Blood flow; Mechanotransduction; ATP synthase
25.  Simultaneous Phenotyping and Quantitation of α-1-Antitrypsin by liquid chromatography-tandem mass spectrometry 
Clinical Chemistry  2011;57(8):1161-1168.
Background
α-1-antitrypsin (A1AT) deficiency results from a genetic disorder at two common loci. Diagnosis requires quantitation of A1AT and subsequent identification of the specific variant. The current algorithm of laboratory testing for the diagnosis of A1AT deficiency uses a combination of quantitation (nephelometry), genotyping and/or phenotyping. We developed a novel multiple reaction monitoring LC-MS/MS method for simultaneous quantitation of A1AT and the identification of the two most common deficiency alleles present in 95% of the patients with A1AT deficiency.
Method
Serum samples (n=40) were digested with trypsin and appropriate 13C/15N-labeled standard peptides added. LC-MS/MS analysis was performed with a 0.5×150 mm C18 column and H2O:acetonitrile:n-propanol (A:98/1/1/0.2 and B:10/80/10/0.2; 12 μL/min) mobile phase in positive ion mode on a TSQ Quantum triple quadrupole MS system. The A1AT concentration was obtained by comparison to a calibration curve and the phenotype by the presence or absence of variant peptides. Results were compared to the current phenotyping assay by isoelectric focusing (IEF) and the immunonephelometry quantitative assay.
Results
For the A1AT allele detection, in 39 of 40 samples, the LC-MS/MS results were identical to those obtained by IEF gel electrophoresis. The single discrepant result was rerun by IEF at a lower dilution and the results were in concordance. The A1AT quantitation by LC-MS/MS also compared favorably with nephelometry.
Conclusion
This LC-MS/MS method correlates well with current phenotyping and nephelometric assays. It is a promising method with the potential to improve the laboratory diagnosis of genetic A1AT deficiency.
doi:10.1373/clinchem.2011.163006
PMCID: PMC3275912  PMID: 21636698
α-1-antitrypsin deficiency; multiple reaction monitoring (MRM); mass spectrometry; LC-MS/MS; proteotypic peptides; IEF alternative

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