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1.  Association between Hemorrhagic Fever with Renal Syndrome Epidemic and Climate Factors in Heilongjiang Province, China 
The purpose of this study was to quantify the relationship between climate variation and transmission of hemorrhagic fever with renal syndrome (HFRS) in Heilongjiang Province, a highly endemic area for HFRS in China. Monthly notified HFRS cases and climatic data for 2001–2009 in Heilongjiang Province were collected. Using a seasonal autoregressive integrated moving average model, we found that relative humidity with a one-month lag (β = –0.010, P = 0.003) and a three-month lag (β = 0.008, P = 0.003), maximum temperature with a two-month lag (β = 0.082, P = 0.028), and southern oscillation index with a two-month lag (β = –0.048, P = 0.019) were significantly associated with HFRS transmission. Our study also showed that predicted values expected under the seasonal autoregressive integrated moving average model were highly consistent with observed values (Adjusted R2 = 83%, root mean squared error = 108). Thus, findings may help add to the knowledge gap of the role of climate factors in HFRS transmission in China and also assist national local health authorities in the development/refinement of a better strategy to prevent HFRS transmission.
PMCID: PMC3820312  PMID: 24019443
2.  Genetic variants in STAT4 and HLA-DQ genes confer risk of hepatitis B virus–related hepatocellular carcinoma 
Nature genetics  2012;45(1):72-75.
To identify genetic susceptibility loci for hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) in the Chinese population, we carried out a genome-wide association study (GWAS) in 2,514 chronic HBV carriers (1,161 HCC cases and 1,353 controls) followed by a 2-stage validation among 6 independent populations of chronic HBV carriers (4,319 cases and 4,966 controls). The joint analyses showed that HCC risk was significantly associated with two independent loci: rs7574865 at STAT4, Pmeta = 2.48 × 10−10, odds ratio (OR) = 1.21; and rs9275319 at HLA-DQ, Pmeta = 2.72 × 10−17, OR = 1.49. The risk allele G at rs7574865 was significantly associated with lower mRNA levels of STAT4 in both the HCC tissues and nontumor tissues of 155 individuals with HBV-related HCC (Ptrend = 0.0008 and 0.0002, respectively). We also found significantly lower mRNA expression of STAT4 in HCC tumor tissues compared with paired adjacent nontumor tissues (P = 2.33 × 10−14).
PMCID: PMC4105840  PMID: 23242368
3.  Interspinous Spacer versus Traditional Decompressive Surgery for Lumbar Spinal Stenosis: A Systematic Review and Meta-Analysis 
PLoS ONE  2014;9(5):e97142.
Dynamic interspinous spacers, such as X-stop, Coflex, DIAM, and Aperius, are widely used for the treatment of lumbar spinal stenosis. However, controversy remains as to whether dynamic interspinous spacer use is superior to traditional decompressive surgery.
Medline, Embase, Cochrane Library, and the Cochrane Controlled Trials Register were searched during August 2013. A track search was performed on February 27, 2014. Study was included in this review if it was: (1) a randomized controlled trial (RCT) or non-randomized prospective comparison study, (2) comparing the clinical outcomes for interspinous spacer use versus traditional decompressive surgery, (3) in a minimum of 30 patients, (4) with a follow-up duration of at least 12 months.
Two RCTs and three non-randomized prospective studies were included, with 204 patients in the interspinous spacer (IS) group and 217 patients in the traditional decompressive surgery (TDS) group. Pooled analysis showed no significant difference between the IS and TDS groups for low back pain (WMD: 1.2; 95% CI: −10.12, 12.53; P = 0.03; I2 = 66%), leg pain (WMD: 7.12; 95% CI: −3.88, 18.12; P = 0.02; I2 = 70%), ODI (WMD: 6.88; 95% CI: −14.92, 28.68; P = 0.03; I2 = 79%), RDQ (WMD: −1.30, 95% CI: −3.07, 0.47; P = 0.00; I2 = 0%), or complications (RR: 1.39; 95% CI: 0.61, 3.14; P = 0.23; I2 = 28%). The TDS group had a significantly lower incidence of reoperation (RR: 3.34; 95% CI: 1.77, 6.31; P = 0.60; I2 = 0%).
Although patients may obtain some benefits from interspinous spacers implanted through a minimally invasive technique, interspinous spacer use is associated with a higher incidence of reoperation and higher cost. The indications, risks, and benefits of using an interspinous process device should be carefully considered before surgery.
PMCID: PMC4014612  PMID: 24809680
4.  Nuclear p27 Expression Confers a Favorable Outcome for Nasopharyngeal Carcinoma Patients 
Disease Markers  2013;35(6):925-932.
Objective. The purpose of the present study is to explore the correlation between nuclear expression of cyclin-dependent kinase inhibitor 1B (p27) and clinicopathologic features in nasopharyngeal carcinoma (NPC), including patient survival. Methods. Immunohistochemistry was used to examine the expression of p27 in 130 primary NPC tissues. The relationship between the levels of p27 expression and clinicopathologic characteristics was analyzed. Survival curves were plotted using the Kaplan-Meier method and compared using the log-rank test. The significance of various survival variables was analyzed using multivariate Cox proportional hazards model. Results. p27 was expressed in both nuclear and cytoplasmic compartments. Nuclear expression of p27 was inversely correlated with T classification and clinical stage. Patients with nuclear p27 expression had better overall survival rates than those without nuclear expression of p27. Further, we observed that nuclear expression of p27 was positively associated with survival time of NPC patients not only in N0-1 and M0 classifications but also in radiotherapy and chemotherapy treatment groups. Finally, we found that nuclear expression of p27 was not an independent prognostic factor for patients with NPC. Conclusions. Our findings hint that nuclear expression of p27 is a potentially favorable factor in the progression and prognosis of NPC.
PMCID: PMC3881392  PMID: 24427780
5.  Metastasis-associated protein 1 induces VEGF-C and facilitates lymphangiogenesis in colorectal cancer 
AIM: To study the correlation between high metastasis-associated protein 1 (MTA1) expression and lymphangiogenesis in colorectal cancer (CRC) and its role in production of vascular endothelial growth factor-C(VEGF-C).
METHODS: Impact of high MTA1 and VEGF-C expression levels on disease progression and lymphovascular density (LVD, D2-40-immunolabeled) in 81 cases of human CRC was evaluated by immunohistochemistry. VEGF-C mRNA and protein expressions in human LoVo and HCT116 cell lines were detected by real-time polymerase chain reaction and Western blotting, respectively, with a stable expression vector or siRNA.
RESULTS: The elevated MTA1 and VEGF-C expression levels were correlated with lymph node metastasis and Dukes stages (P < 0.05). Additionally, high MTA1 expression level was correlated with a large tumor size (P < 0.05). A significant correlation was found between MTA1 and VEGF-C protein expressions in tumor cells (r = 0.371, P < 0.05). Similar to the VEGF-C expression level, high MTA1 expression level was correlated with high LVD in CRC (P < 0.05). Furthermore, over-expression of MTA1 significantly enhanced the VEGF-C mRNA and protein expression levels, whereas siRNAs - knocked down MTA1 decreased the VEGF-C expression level.
CONCLUSION: MTA1, as a regulator of tumor-associated lymphangiogenesis, promotes lymphangiogenesis in CRC by mediating the VEGF-C expression.
PMCID: PMC3063917  PMID: 21448429
Metastasis-associated protein 1; Vascular endothelial growth factor-C; Lymphangiogenesis; Colorectal cancer
6.  Silencing collapsin response mediator protein-2 reprograms macrophage phenotype and improves infarct healing in experimental myocardial infarction model 
Delayed M1 toward M2 macrophage phenotype transition is considered one of the major causes for the impaired healing after myocardial infarction (MI). While searching for molecules that modulate M1 and M2 macrophage polarization, we identified collapsin response mediator protein-2 (CRMP2) as a novel molecule involved in macrophage polarization to M1. In this study, we evaluated the effect of silencing CRMP2 on macrophage polarization, inflammation and fibrosis post myocardial infarction.
CRMP2 expression was assessed with Western blotting or immunohistochemistry. Macrophage phenotypes were measured with flow cytometry, quantitative real-time PCR (qPCR), Western blotting or immunohistochemistry. CRMP2 siRNA was delivered into the macrophages infiltrated in the wound of ApoE−/− mice through lipidoid nanoparticle, and fibrosis, leukocyte infiltration and inflammation parameters were measured with qPCR. Infarct size was measured with Masson’s trichrome staining. Echocardiography was performed to assess ventricular systolic dimension, left ventricular diastolic dimension, anterior wall thickness and posterior wall thickness. Student’s t-test (for 2 groups) and ANOVA (for > 2 groups) were used for statistical analyses.
CRMP2 was expressed in a higher level in M1 macrophages than M2 subsets, and CRMP2 RNA interference (RNAi) resulted in a switch of bone marrow-derived macrophages from M1 to M2 phenotype. High level of CRMP2 was also observed in the macrophages infiltrated in the infarct area 3 days post MI in both wildtype (WT) and ApoE−/− mice, and the expression of CRMP2 retained in the infiltrated macrophages of ApoE−/− mice but not in that of WT mice 10 days after MI. Nanoparticle-mediated delivery of CRMP2 siRNA to ApoE−/− mice with MI resulted in dramatic switch of wound macrophages from M1 to M2 phenotype, marked decrease in inflammation and fibrosis, and significant attenuation of post-MI heart failure and mortality.
CRMP2 is highly expressed in M1 macrophages and silencing CRMP2 reprograms macrophage phenotype and improves infarct healing in atherosclerotic mice.
PMCID: PMC4328069
Collapsin response mediator protein-2; Macrophages; Phenotypes; Inflammation; ApoE−/−; Myocardial infarction; Fibrosis
7.  Surgical Outcomes of 2041 Consecutive Laparoscopic Gastrectomy Procedures for Gastric Cancer: A Large-Scale Case Control Study 
PLoS ONE  2015;10(2):e0114948.
Laparoscopic gastrectomy (LG) for gastric cancer has increased in popularity due to advances in surgical techniques. The aim of this study is to validate the efficacy and safety of laparoscopic gastrectomy for gastric cancer compared with open gastrectomy (OG).
The study comprised 3,580 patients who were treated with curative intent either by laparoscopic gastrectomy (2,041 patients) or open gastrectomy (1,539 patents) between January 2005 and October 2013. The surgical outcomes were compared between the two groups.
Laparoscopic gastrectomy was associated with significantly less blood loss, transfused patient number, time to ground activities, and post-operative hospital stay, but with similar operation time, time to first flatus, and time to resumption of diet, compared with the open gastrectomy. No significant difference in the number of lymph nodes dissected was observed between these two groups. The morbidity and mortality rates of the LG group were comparable to those of the OG group (13.6% vs. 14.4%, P = 0.526, and 0.3% vs. 0.2%, P = 0.740). The 3-year disease-free and overall survival rates between the two groups were statistically significant (P<0.05). According to the UICC TNM classification of gastric cancer, the 3-year disease-free and overall survival rates were not statistically different at each stage.
Our single-center study of a large patient series revealed that LG for gastric cancer yields comparable surgical outcomes. This result was also true of local advanced gastric cancer (AGC). A well-designed randomized controlled trial comparing surgical outcomes between LG and OG in a larger number of patients for AGC can be carried out.
PMCID: PMC4314075  PMID: 25642698
8.  Prognostic Value of Tumor Size in Patients with Remnant Gastric Cancer: Is the Seventh UICC Stage Sufficient for Predicting Prognosis? 
PLoS ONE  2014;9(12):e115776.
The 7th UICC N stage may be unsuitable for remnant gastric cancer (RGC) because the original disease and previous operation usually cause abnormal lymphatic drainage. However, the prognostic significance of the current TNM staging system in RGC has not been studied.
Prospective data from 153 RGC patients who underwent curative gastrectomy from Jan 1995 to Aug 2009 were reviewed. All patients were classified according to tumor size (<3 cm as N0;>3&≤5 cm as N1;>5&≤7 cm as N2; and>7 cm as N3). The overall survival was estimated using the Kaplan-Meier method, and hazard ratios (HRs) were calculated using the Cox proportional hazard model.
Tumor sizes ranged from 1.0 to 15.0 cm (median 5.0 cm). Tumor size, depth of invasion and lymph node (LN) metastasis were significant prognostic factors based on both the univariate and multivariate analyses (P<0.05). In the survival analysis, the seventh edition UICC-TNM classification provided a detailed classification; however, some subgroups of the UICC-TNM classification did not have significantly different survival rates. The combination of the seventh edition T classification and the suggested N classification, with ideal relative risk (RR) results and P value, was distinctive for subgrouping the survival rates except for the IA versus IB and II A versus IIB. A modified staging system based on tumor size, predicted survival more accurately than the conventional TNM staging system.
In RGCs, tumor size is an independent prognostic factor and a modified TNM system based on tumor size accurately predicts survival.
PMCID: PMC4280110  PMID: 25549339
9.  Effect of CETP Polymorphism on Atorvastatin Lipid-Regulating Effect and Clinical Prognosis of Patients with Coronary Heart Disease 
The aim of this study was to investigate the influence of genetic polymorphism of cholesteryl ester transfer protein (CETP) gene polymorphism −629C/A on the therapeutic effect of atorvastatin and clinical outcome in Han Chinese patients with coronary heart disease (CHD).
From October 2011 to December 2012, 348 patients with angiographically confirmed CHD were recruited. CETP gene polymorphism was determined by polymerase chain reaction-restricted fragment length polymorphism (PCR-RFLP) method. Serum level of CETP was determined with enzyme-1inked immunosorbent assay (ELISA). Lipid 1evel in all patients was determined at baseline and after 12 months of treatment with 20 mg/d of atorvastatin. All the patients were followed-up at least 12 months. Major adverse cardiac events, including death, non-fatal infarction, revascularization, and stroke (MACE), were recorded.
The frequency of the −629A allele was 0.412. Compared with CC or CA genotypes, individuals with AA genotype had lower CETP levels (P=0.026) and higher high-density lipoprotein cholesterol (HDL-C) levels (P=0.035). After 12 months of atorvastatin therapy, carriers with CC genotype had greater reduction of low-density lipoprotein cholesterol (LDL-C) (P<0.001), reduced LP (a) (P=0.005), and elevated HDL-C (P=0.045) compared with CA or AA genotypes. The incidence of MACE after a mean follow-up of 17.3±5.2 months was 8.8%. The cumulative MACE-free survival rates were 90.1%, 85.2%, and 71.1% for CC, CA, and AA genotypes, respectively.
Our results suggest that the AA variant of the −629A allele of CETP gene had higher HDL-C levels and reduced CETP levels, but patients with CC genotype appeared to have benefited more from statin therapy with reduction in LDL-C and LP (a) levels. Long-term clinical prognosis was, however, not affected by the 3 genotypes.
PMCID: PMC4285921  PMID: 25547030
Cholesterol, HDL; Genetics; Lipid A
10.  Three-field vs two-field lymph node dissection for esophageal cancer: A meta-analysis 
World Journal of Gastroenterology : WJG  2014;20(47):18022-18030.
AIM: To assess the effects of 3-field lymphadenectomy for esophageal carcinoma.
METHODS: We conducted a computerized literature search of the PubMed, Cochrane Controlled Trials Register, and EMBASE databases from their inception to present. Randomized controlled trials (RCTs) or observational epidemiological studies (cohort studies) that compared the survival rates and/or postoperative complications between 2-field lymphadenectomy (2FL) and 3-field lymphadenectomy (3FL) for esophageal carcinoma with R0 resection were included. Meta-analysis was conducted using published data on 3FL vs 2FL in esophageal carcinoma patients. End points were 1-, 3-, and 5-year overall survival rates and postoperative complications, including recurrent nerve palsy, anastomosis leak, pulmonary complications, and chylothorax. Subgroup analysis was performed on the involvement of recurrent laryngeal lymph nodes.
RESULTS: Two RCTs and 18 observational studies with over 7000 patients were included. There was a clear benefit for 3FL in the 1- (RR = 1.16; 95%CI: 1.09-1.24; P < 0.01), 3- (RR = 1.44; 95%CI: 1.19-1.75; P < 0.01), and 5-year overall survival rates (RR = 1.37; 95%CI: 1.18-1.59; P < 0.01). For postoperative complications, 3FL was associated with significantly more recurrent nerve palsy (RR = 1.43; 95%CI: 1.28-1.60; P = 0.02) and anastomosis leak (RR = 1.26; 95%CI: 1.05-1.52; P = 0.09). In contrast, there was no significant difference for pulmonary complications (RR = 0.93; 95%CI: 0.75-1.16, random-effects model; P = 0.27) or chylothorax (RR = 0.77; 95%CI: 0.32-1.85; P = 0.69).
CONCLUSION: This meta-analysis shows that 3FL improves overall survival rate but has more complications. Because of the high heterogeneity among outcomes, definite conclusions are difficult to draw.
PMCID: PMC4273154  PMID: 25548502
Oesophagus; Cancer; Lymph node dissection; Survival; Complication
11.  Apoptosis of bone marrow mesenchymal stem cells caused by hypoxia/reoxygenation via multiple pathways 
The irreversible loss of cardiomyocytes remains a key problem to resolve, which forms the cellular basis of cardiac dysfunction. MSCs transplantation brings out a promising potential for myocardial renovation with less limitations. However, this cell transplantation therapy is limited by its poor viability after transplantation. Apoptosis is thought to be the major factor that affects the efficiency of MSCs transplantation. Therefore, exploring the process of apoptosis and the underlying mechanisms of MSCs in the ‘harmful’ microenvironment is significant for the sake of improving the efficiency of MSCs transplantation therapy. A hypoxia/reoxygenation (H/R) model of MSCs had been established. TUNEL, Hoechst staining and MTT were used for the evaluation of morphological changes, cell viability and apoptosis. Mitochondrial transmembrane potential was detected by JC-1 using the fluorescence microscopy system. The protein expression of cytochrome c, p-ERK, p-AKT, Bcl-2, Bax, p-JNK, HIF-1α and VEGF was assessed for the analysis of protein changes using the Western blot. In our study, H/R insult lead to apoptosis and cell viability lost in a time-dependent manner in MSCs. Multiple pathways were involved in the apoptosis of MSCs, including cytochrome c released from mitochondria to cytosol, mitochondrial transmembrane potential lost. In addition, p-ERK and p-AKT were downregulated, while Bcl-2, p-JNK and VEGF were upregulated. H/R induced the apoptosis in MSCs is through multiple pathways. These multiple pathways will be helpful for understanding and explaining the process and mechanism of apoptosis in MSCs.
PMCID: PMC4307413  PMID: 25663966
MSCs; apoptosis; cytochrome c; transmembrane potential; ERK; Akt; JNK; Bcl-2; Bax; HIF-1α; VEGF
12.  Short-term pretreatment with atorvastatin attenuates left ventricular dysfunction, reduces infarct size and apoptosis in acute myocardial infarction rats 
Background: Atorvastatin showed a number of cardiovascular benefits, however, the role and underlying molecular mechanisms of short-term atorvastatin-mediated protection remain unclear. Methods: 30 rats were randomly divided into 3 groups: sham group, acute myocardial infarction model group and atorvastatin group. The rats of acute myocardial infarction model were established by ligation of the left anterior descending of coronary arteries. Before surgery, rats in the atorvastatin group received 20 mg/kg/d atorvastatin for 7 days in atorvastatin group. After 4 hours of model established, changes in hemodynamics parameters were recorded and myocardial infarct size was achieved by Evans blue-TTC staining. Myocardium apoptosis was evaluated by TUNEL. The expression of FAS, FAS-L, Bcl-2, Bax, p-BAD, Caspase-8 and Caspase-3 in myocardium were examined by Western blot. Results: In the atorvastatin group, left ventricular function was elevated and infarct size was decreased compared with the model group. Moreover, in the atorvastatin group, the cell apoptosis index was reduced in response to myocardial infarction. The expressions of Bcl-2 were increased and Bax, p-BAD, Fas, Fas-L, caspase-8 and caspase-3 in myocardium were decreased in atorvastatin group. Conclusions: Short-term atorvastatin pretreatment restored left ventricular function and limited infarct size in acute myocardial infarction, which were associated with reduction of the apoptosis in myocardium through Bcl-2 and Fas pathway.
PMCID: PMC4307423  PMID: 25663976
Atorvastatin; myocardial infarction; left ventricular function; apoptosis; Bcl-2; Fas
13.  Spatiotemporal Transmission Dynamics of Hemorrhagic Fever with Renal Syndrome in China, 2005–2012 
Hemorrhagic fever with renal syndrome (HFRS) is a rodent-borne disease caused by many serotypes of hantaviruses. In China, HFRS has been recognized as a severe public health problem with 90% of the total reported cases in the world. This study describes the spatiotemporal dynamics of HFRS cases in China and identifies the regions, time, and populations at highest risk, which could help the planning and implementation of key preventative measures.
Data on all reported HFRS cases at the county level from January 2005 to December 2012 were collected from Chinese Center for Disease Control and Prevention. Geographic Information System-based spatiotemporal analyses including Local Indicators of Spatial Association and Kulldorff's space-time scan statistic were performed to detect local high-risk space-time clusters of HFRS in China. In addition, cases from high-risk and low-risk counties were compared to identify significant demographic differences.
A total of 100,868 cases were reported during 2005–2012 in mainland China. There were significant variations in the spatiotemporal dynamics of HFRS. HFRS cases occurred most frequently in June, November, and December. There was a significant positive spatial autocorrelation of HFRS incidence during the study periods, with Moran's I values ranging from 0.46 to 0.56 (P<0.05). Several distinct HFRS cluster areas were identified, mainly concentrated in northeastern, central, and eastern of China. Compared with cases from low-risk areas, a higher proportion of cases were younger, non-farmer, and floating residents in high-risk counties.
This study identified significant space-time clusters of HFRS in China during 2005–2012 indicating that preventative strategies for HFRS should be particularly focused on the northeastern, central, and eastern of China to achieve the most cost-effective outcomes.
Author Summary
Hemorrhagic fever with renal syndrome (HFRS) is a rodent-borne viral disease caused by many serotypes of hantaviruses. In China, HFRS has been recognized as a severe public health problem and accounts for 90% of the reported cases in the world. We examined the spatiotemporal dynamics of HFRS cases in China during 2005–2012 and compared characteristics between cases from high-risk and low-risk counties. Several distinct HFRS cluster areas were identified, concentrated in northeastern, central, and eastern of China. Compared with cases from low-risk areas, a higher proportion of cases were younger, non-farmer, and floating residents in high-risk counties. These findings suggest preventative strategies for HFRS should be focused on the identified clusters in order to achieve the most cost-effective outcomes.
PMCID: PMC4239011  PMID: 25412324
14.  Toxic Effects of Levofloxacin on Rat Annulus Fibrosus Cells: An In-vitro Study 
Fluoroquinolones are in wide clinical use as safe and effective antibiotics. Articular cartilage, tendons, and epiphyseal growth plates have been recognized as targets of fluoroquinolone-induced connective tissue toxicity. However, the effects of fluoroquinolones on annulus fibrosus (AF) cells are still unknown.
The main objective of this study was to investigate the effects of levofloxacin, a typical fluoroquinolone antibiotic drug, on rat AF cells in vitro. Rat annulus fibrosus (RAF) cells were treated with levofloxacin at different concentrations (0, 10, 20, 30, 40, 60, 80, and 90 μg/ml) and were assessed to determine the possible cytotoxic effects of levofloxacin. Inverted phase-contrast microscopy was used to accomplish the morphological observation of apoptosis of treated cells. Western blot and real-time quantitative RT-PCR (qPCR) was used to explore the expression of active caspase-3 and MMP-3. Flow cytometry was used to measure the apoptotic incidences.
Our study showed that levofloxacin, with concentrations at 30, 60, and 90 μg/ml, induced dose-dependent RAF cell apoptosis and higher expression of caspase-3 and MMP-3. More apoptotic cells were observed by inverted phase-contrast microscopy. Moreover, levofloxacin increased the activity of caspase-3, and it also reduced cell viability with different concentrations ranging from 10 to 80 μg/ml.
Our study results suggest that levofloxacin has cytotoxic effects on RAF cells, characterized by enhancing apoptosis and reducing cell viability, and indicate a potential toxic effect of fluoroquinolones on RAF cells.
PMCID: PMC4237079  PMID: 25380657
Apoptosis; Caspase 3; Cell Survival; Levofloxacin
15.  In-situ X-ray diffraction snapshotting: Determination of the kinetics of a photodimerization within a single crystal 
Scientific Reports  2014;4:6815.
In a single-crystal-to-single-crystal (SCSC) transformation, a preformed three-dimensional coordination polymer,[Ni3(oba)2(bpe)2(SO4)(H2O)4]·H2O (H2oba = 4,4′-oxydibenzoic acid; bpe = (E)-1,2-di(pyridin-4-yl)ethane) (1), was shown to undergo a [2+2] cycloaddition reaction upon exposure to UV irradiation. The kinetics of this reaction were followed by taking “snapshots” of the solid state transformation using in situ single crystal X-ray crystallography; a first order process was indicated. The reaction rate was influenced by many factors such as the separation of the sample from the UV light source, the heat produced by the UV irradiation, the light flux of the UV lamp used, the size of the single-crystal and the powder samples. The investigation of the kinetics was complemented by 1H NMR studies. The results clearly demonstrate that in situ single-crystal X-ray diffraction is able to provide useful insights into the gradual formation of the photoproducts and the reaction processes. The work also offers a clear indication that it is possible to use the technique to study the kinetics of other photocycloaddition reactions and SCSC processes in general.
PMCID: PMC4212243  PMID: 25351677
16.  Polymorphism Ala54Thr of Fatty Acid-Binding Protein 2 Gene is Not Associated with Stroke Risk in Han Population of Hunan China 
It is still unclear which genetic factors have a role in stroke. Studies have found that Ala54Thr of Fatty Acid-Binding Protein 2 (FABP2) was associated with stroke risk. This study aimed to determine whether polymorphism Ala54Thr of FABP2 is associated with stroke risk in the Hunan Han population of China.
A total of 206 cerebral infarction (CI) patients, 185 cerebral hemorrhage (CH) patients, and 172 controls were enrolled in this study. Ala54Thr genotyping was done by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP).
No significant difference was observed in genotypic distribution of FABP2 Ala54Thr between the stroke group (CI subgroup, CH subgroup included) and control group. In the stroke group, plasma triglycerides (TG) levels of subjects who carried Ala/Thr, Thr/Thr were significantly higher than those carrying Ala/Ala. In the control group, blood lipids were not significantly different among 3 genotypes of Ala54Thr. There was no significant difference in blood pressure and fasting blood sugar between the stroke group and controls.
Our study showed that Ala54Thr of FABP2 may be not associated with stroke risk but may be associated with plasma TG level of stroke patients from a Hunan Han population of China.
PMCID: PMC4188191  PMID: 25262933
Cerebral Hemorrhage; Cerebral Infarction; Fatty Acid-Binding Proteins; Polymorphism, Genetic; Polymorphism, Restriction Fragment Length; Stroke
17.  Clostridium difficile carriage in hospitalized cancer patients: a prospective investigation in eastern China 
BMC Infectious Diseases  2014;14(1):523.
Clostridium difficile carriage has been considered as a potential source for the deadly infection, but its role in cancer patients is still unclear. We aimed to identify the clinical and immunological factors that are related to C. difficile carriage in Chinese cancer patients.
A total of 400 stool samples were collected from cancer patients who received chemotherapy in three hospitals of eastern China. Bacterial genomic DNA was extracted and two toxin genes (tcdA and tcdB) were detected. PCR ribotyping was performed using capillary gel electrophoresis. Concentrations of prostaglandin E2 (PGE2), transforming growth factor beta (TGF-β) and interleukin-10 (IL-10) were measured using enzyme-linked immunosorbent assay (ELISA) kits.
Eighty-two (20.5%) samples were confirmed to be C. difficile-positive and positive for tpi, tcdA, and tcdB genes. The C. difficile-positive rates in patients with diarrhea and no diarrhea were 35% and 19.7%, respectively (p = 0.09). Patients who were younger than 50 years old and were hospitalized for at least 10 days had a C. difficile-positive rate as high as 35%. In contrast, patients who were older than 50 years old and were hospitalized for less than 10 days had a C. difficile-positive rate of only 12.7% (p = 0.0009). No association was found between C. difficile carriage and chemotherapy regimen, antibiotic drug use, or immunosuppressive mediators, such as prostaglandin E2 (PGE2), transforming growth factor beta (TGF-β), or interleukin-10 (IL-10). Twelve ribotypes of C. difficile were identified, but none of them belonged to ribotype 027.
We conclude that younger patients and those with longer hospitalization stays may be more prone to C. difficile carriage. Studies of larger populations are warranted to clarify the exact role of C. difficile carriage in hospitalized cancer patients in China.
PMCID: PMC4261591  PMID: 25267108
Clostridium difficile; Carriage; Age; Hospitalization days
18.  Aberrant neuronal synaptic connectivity in CA1 area of the hippocampus from pilocarpine-induced epileptic rats observed by fluorogold 
In this study, we observed synaptic connectivity among neurons in CA1 region of pilocarpine-induced chronic seizures in rats. Twenty healthy male Sprague-Dawley rats were divided randomly into an epilepsy group (n = 10) and a control group (n = 10). Approximately 60 days after status epilepticus (SE) , Fluorogold (FG) was injected into the CA1 area of the hippocampus in vivo. Somatostatin (SS) expression was observed using immunofluorescence. The distribution of FG-positive and FG/SS double-labeled neurons was observed using a confocal microscope. FG-labeled pyramidal cells could be seen remotely from the FG-injected site in the CA1 area and in the subiculum in the experimental group. FG/SS double-labeled interneurons were distributed remotely from the FG-injected site in the CA1 area in the epileptic rats. These changes suggest aberrant neuronal connectivity in CA1 region, which may lead to the formation of aberrant excitatory and inhibitory circuitry, and may play an important role in the generation or compensation for temporal lobe epilepsy.
PMCID: PMC4211776  PMID: 25356126
Temporal lobe epilepsy (TLE); fluorogold (FG); somatostatin (SS); neuronal connectivity; circuit rearrangement; interneuron; lithium chloride; pilocarpin
19.  Sirtuin 1 Regulates Hepatitis B Virus Transcription and Replication by Targeting Transcription Factor AP-1 
Journal of Virology  2014;88(5):2442-2451.
Chronic hepatitis B virus (HBV) infection is a major risk factor for liver cirrhosis and hepatocellular carcinoma. Nevertheless, the molecular mechanism of HBV replication remains elusive. SIRT1 is a class III histone deacetylase that is a structure component of the HBV cccDNA minichromosome. In this study, we found by using microarray-based gene expression profiling analysis that SIRT1 was upregulated in HBV-expressing cells. Gene silencing of SIRT1 significantly inhibited HBV DNA replicative intermediates, 3.5-kb mRNA, and core protein levels. In contrast, the overexpression of SIRT1 augmented HBV replication. Furthermore, SIRT1 enhanced the activity of HBV core promoter by targeting transcription factor AP-1. The c-Jun subunit of AP-1 was bound to the HBV core promoter region, as demonstrated by using a chromatin immunoprecipitation assay. Mutation of AP-1 binding site or knockdown of AP-1 abolished the effect of SIRT1 on HBV replication. Finally, SIRT1 inhibitor sirtinol also suppressed the HBV DNA replicative intermediate, as well as 3.5-kb mRNA. Our study identified a novel host factor, SIRT1, which may facilitate HBV replication in hepatocytes. These data suggest a rationale for the use of SIRT1 inhibitor in the treatment of HBV infection.
PMCID: PMC3958108  PMID: 24335313
20.  Prolonged Neuroinflammation after Lipopolysaccharide Exposure in Aged Rats 
PLoS ONE  2014;9(8):e106331.
Inflammation is a hallmark of several disease states ranging from neurodegeneration to sepsis but is also implicated in physiological processes like ageing. Non-resolving inflammation and prolonged neuroinflammation are unclear processes implicated in several conditions, including ageing. In this study we studied the long-term effects of endotoxemia, as systemic lipopolysaccharide (LPS) injection, focusing on the role of astrocyte activation and cytokine release in the brain of aged rats. A single dose of LPS (2 mg/kg) or 0.9% saline was injected intraperitoneally in aged rats. Levels of pro-inflammatory cytokines (TNFα and IL-1β) and NF-κB p65 activation were measured systemically and in hippocampal tissue. Astrocytes and cytokines release in the CNS were detected via double immunofluorescence staining at different time-points up to day 30. Serum levels of TNFα and IL-1β were significantly increased acutely after 30 minutes (p<0.001) and up to 6 hours (p<0.001) following LPS-injection. Centrally, LPS-treated rats showed up-regulated mRNA expression and protein levels of pro-inflammatory cytokines in the hippocampus. These changes associated with astrogliosis in the hippocampus dentate gyrus (DG), IL-1β immunoreactivity and elevated NF-κB p65 expression up to day 30 post LPS exposure. Overall, these data demonstrate that LPS induces prolonged neuroinflammation and astrocyte activation in the hippocampus of aged rats. Hippocampal NF-κB p65 and excessive astrocytes-derived IL-1β release may play a pivotal role in regulating long-lasting neuroinflammation.
PMCID: PMC4149545  PMID: 25170959
21.  RNA interference-mediated knockdown of Aurora-B alters the metastatic behavior of A549 cells via modulation of the phosphoinositide 3-kinase/Akt signaling pathway 
Oncology Letters  2014;8(5):2063-2068.
Accumulating evidence has revealed that an elevated expression level of Aurora-B is associated with metastasis in various types of malignant tumor. However, it is currently unclear whether this molecule is involved in non-small lung cancer (NSCLC) metastasis, and the molecular mechanisms associated with Aurora-B and metastasis remain unknown. In the present study, in order to investigate whether Aurora-B is involved in the development and metastasis of NSCLC, the Aurora-B protein expression in NSCLC tissues was detected by immunohistochemistry and its association with metastasis was analyzed. The results revealed that the expression levels of the Aurora-B protein in tissues obtained from NSCLC patients with lymph node metastasis were significantly higher than those without metastatic disease. Furthermore, the effect of Aurora-B inhibition on A549 cell migration and invasion, as well as the activity of the phosphoinositide 3-kinase (PI3K)/Akt signaling pathway was evaluated. Aurora-B was inhibited in the A549 cells using short hairpin RNA, and the cell migration and invasion rates were investigated using wound healing and Transwell invasion assays. In addition, the expression of the main proteins in the PI3K/Akt/nuclear factor-κB (NF-κB) signaling pathway, and matrix metalloproteinase (MMP)-2 and -9 were measured by western blot analysis. The results demonstrated that cell migration and invasion were decreased as a result of silencing Aurora-B. Furthermore, the activity of the PI3K/Akt/NF-κB signaling pathway and the expression of MMP-2 and -9 protein were suppressed by silencing Aurora-B. The results of the present study indicate that the knockdown of Aurora-B suppresses A549 cell invasion and migration via the inhibition of the PI3K/Akt signaling pathway in vitro and thus, targeting Aurora-B may present a potential treatment strategy for NSCLC.
PMCID: PMC4186632  PMID: 25295091
non-small cell lung cancer; Aurora B; metastasis; phosphoinositide 3-kinase/Akt signaling pathway
22.  Rapamycin protects kidney against ischemia reperfusion injury through recruitment of NKT cells 
NKT cells play a protective role in ischemia reperfusion (IR) injury, of which the trafficking in the body and recruitment in injured organs can be influenced by immunosuppressive therapy. Therefore, we investigated the effects of rapamycin on kidneys exposed to IR injury in early stage and on trafficking of NKT cells in a murine model.
Material and methods
Balb/c mice were subjected to kidney 30 min ischemia followed by 24 h reperfusion. Rapamycin (2.5 ml/kg) was administered by gavage daily, starting 1 day before the operation. Renal function and histological changes were assessed. The proportion of NKT cells in peripheral blood, spleen and kidney was detected by flow cytometry. The chemokines and corresponding receptor involved in NKT cell trafficking were determined by RT-PCR and flow cytometry respectively.
Rapamycin significantly improved renal function and ameliorated histological injury. In rapamycin-treated group, the proportion of NKT cells in spleen was significantly decreased but increased in peripheral blood and kidney. In addition, the CXCR3+ NKT cell in the kidney increased remarkably in the rapamycin-treated group. The chemokines, CXCL9 and CXCL10, as the ligands of CXCR3, were also increased in the rapamycin-treated kidney.
Rapamycin may recruit NKT cells from spleen to the IR-induced kidney to ameliorate renal IR injury in the early stage.
PMCID: PMC4145235  PMID: 25134448
Rapamycin; Renal ischemia reperfusion injury; NKT cell; Chemokine
23.  Activated microglia contribute to neuronal apoptosis in Toxoplasmic encephalitis 
Parasites & Vectors  2014;7(1):372.
A plethora of evidence shows that activated microglia play a critical role in the pathogenesis of the central nervous system (CNS). Toxoplasmic encephalitis (TE) frequently occurs in HIV/AIDS patients. However, knowledge remains limited on the contributions of activated microglia to the pathogenesis of TE.
A murine model of reactivated encephalitis was generated in a latent infection with Toxoplasma gondii induced by cyclophosphamide. The neuronal apoptosis in the CNS and the profile of pro-inflammatory cytokines were assayed in both in vitro and in vivo experiments.
Microglial cells were found to be activated in the cortex and hippocampus in the brain tissues of mice. The in vivo expression of interleukin-6 (IL-6), interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and inducible nitric oxide synthase (iNOS) were up-regulated in TE mice, and accordingly, the neuronal apoptosis was significantly increased. The results were positively correlated with those of the in vitro experiments. Additionally,apoptosis of the mouse neuroblastoma type Neuro2a (N2a) remarkably increased when the N2a was co-cultured in transwell with microglial cells and Toxoplasma tachyzoites. Both in vivo and in vitro experiments showed that minocycline (a microglia inhibitor) treatment notably reduced microglial activation and neuronal apoptosis.
Activated microglia contribute to neuronal apoptosis in TE and inhibition of microglia activation might represent a novel therapeutic strategy of TE.
PMCID: PMC4143554  PMID: 25128410
Toxoplasmic encephalitis; Microglia; Neuronal apoptosis; Minocycline
24.  miR-183 inhibits invasion of gastric cancer by targeting Ezrin 
miR-183, a member of an evolutionarily conserved miRNA cluster (miR-96, miR-182, and miR-183), has been demonstrated to act as both a tumor suppressor and oncogene in various type of human cancer. However, the biological role of miR-183 in gastric cancer (GC) still remains unclear. In the present study, miR-183 expression was significantly decreased in gastric cancer tissues compared with its’ adjacent normal tissues, and down-regulation of miR-183 was significantly associated with lymph node metastasis and pathological TNM stage. Furthermore, Erzin, which was reported to be up-regulated in gastric cancer, was identified as an efficient target of miR-183. Overexpression of miR-183 markedly suppressed cells invasion by downregulation of Ezrin expression. However, miR-183 expression didn’t affect cells proliferation and cell cycle distribution of GC. In conclusion, our study demonstrated that miR-183 acts as a tumor suppressor in GC, partially at least via regulation of Ezrin. Therefore, miR-183 may be a potential target for the treatment of gastric cancer.
PMCID: PMC4203171  PMID: 25337200
MicroRNA-183; gastric cancer (GC); Ezrin; metastasis
25.  Overexpression and Selectively Regulatory Roles of IL-23/IL-17 Axis in the Lesions of Oral Lichen Planus 
Mediators of Inflammation  2014;2014:701094.
Interleukin- (IL-) 23/IL-17 axis is a newly discovered proinflammatory signaling pathway and has been implicated in the pathogenesis of many chronic inflammatory and immune disorders. Here we investigated whether the IL-23/IL-17 axis was present and functional in the lesions of oral lichen planus (OLP), a chronic inflammatory disease affecting the oral mucosa. Using immunohistochemistry and quantitative PCR, we found that the subunits of IL-23 and IL-17 were overexpressed in OLP lesions than in normal oral mucosa tissues. In addition, the expressions of IL-23 and IL-17 are positively correlated in reticular OLP tissues. Results from in vitro studies revealed that exogenous IL-23 could increase the percentage of Th17 cells and IL-17 production in the CD4+T cells from reticular OLP patients. Furthermore, we also found that exogenous IL-17 could significantly enhance the mRNA expressions of β-defensin-2, -3, CCL-20, IL-8, and TNF-α, but not β-defensin-1, CXCL-9, -10, -11, CCL-5, and IL-6 in human oral keratinocytes. Taken together, our results revealed an overexpression pattern and selectively regulatory roles of IL-23/IL-17 axis in the OLP lesions, suggesting that it may be a pivotal regulatory pathway in the complex immune network of OLP lesions.
PMCID: PMC4121042  PMID: 25114378

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