OBJECTIVE To investigate the inhibitory effects of ursolic acid on interleukin-6 （IL-6）-mediated invasion and migration of breast cancer MDA-MB-231 cells （hereinafter referred to as “231 cells”）. METHODS The effects of 20， 40， 80， 160 and 320 µmol/L ursolic acid on the proliferation rate of 231 cells were measured by CCK-8 method. The breast cancer 231 cells were divided into control group， model group and administration group. The migration and invasion abilities of cells were detected by scratch assay and Transwell assay. Real-time quantitative polymerase chain reaction （q-PCR） assay and Western blot assay were used to detect the mRNA and protein expressions of epithelial-mesenchymal transition-related makers such as E cadherin （E-cad）， matrix metalloprotein 2 （MMP2）， MMP9， vimentin （Vim）， CD44 molecule （CD44） and aldehyde dehydrogenase 1 family member A1 （ALDH1A1）. The phosphorylation levels of JAK2 and STAT3 in the Janus kinase 2/signal transducer and activator of transcription 3 （JAK2/STAT3） signaling pathway （in terms of p-JAK2/JAK2 ratio and p-STAT3/STAT3 ratio） were detected by Western blot assay. RESULTS A low concentration of ursolic acid of 20 µmol/L （no significant inhibitory effect on cell proliferation ability） was selected as the subsequent administration concentration. Compared with the control group， the migration and invasion abilities of cells in the model group were significantly enhanced （P＜0.05）； compared with the model group， the migration and invasion abilities of cells in the administered group were significantly reduced （P＜0.05）. Compared with the control group， the relative mRNA and protein expressions of epithelial-mesenchymal transition-related markers MMP9， MMP2， Vim， ALDH1A1 and CD44 were all elevated to different extents， and the mRNA and protein expressions of E-cad were all decreased to different extents in the model group cells， and part of the differences had statistical significance （P＜0.05）， the p-JAK2/JAK2 ratio and p-STAT3/STAT3 ratio were significantly increased in the model group （P＜0.05）； compared with the model group， the expressions of the above indicators were reversed to some extent in the administration group. CONCLUSIONS Ursolic acid blocks the activation of JAK2/STAT3 signaling pathwby the inflammatory factor IL-6， which ultimately interrupts the invasion and metastasis of breast cancer cells.

Depressive disorder ranks as a major bur-den of disease worldwide,yet the current antidepressant medications are limited by frequent non-responsiveness and significant side effects.The lateral septum(LS)is thought to control of depression,however,the cellular and circuit substrates are largely unknown.Here,we identified a subpopulation of LS GABAergic adenosine A2A receptors(A2AR)-positive neurons mediating depres-sive symptoms via direct projects to the lateral habenula(LHb)and the dorsomedial hypothalamus(DMH).Activa-tion of A2AR in the LS augmented the spiking frequency of A2AR-positive neurons leading to a decreased activation of surrounding neurons and the bi-directional manipula-tion of LS-A2AR activity demonstrated that LS-A2ARs are necessary and sufficient to trigger depressive pheno-types.Thus,the optogenetic modulation(stimulation or inhibition)of LS-A2AR-positive neuronal activity or LS-A2AR-positive neurons projection terminals to the LHb or DMH,phenocopied depressive behaviors.Moreover,A2AR are upregulated in the LS in two male mouse mod-els of repeated stress-induced depression.This identifica-tion that aberrantly increased A2AR signaling in the LS is a critical upstream regulator of repeated stress-induced depressive-like behaviors provides a neurophysiological and circuit-based justification of the antidepressant poten-tial of A2AR antagonists,prompting their clinical transla-tion.

Objective To explore the relationship among psychological flexibility,coping style and job burnout of nurses.Methods A total of 694 nurses from one district level grade A tertiary general hospital in Yunnan were assessed using acceptance and action questionnaire 2nd edition (AAQ-Ⅱ),simplified coping style questionnaire (SCSQ) and nursing burnout scale (NBS).The relationship among psychological flexibility,coping style and job burnout of nurses was analyzed using structural equation model and Bootstrap test.Results (1) Correlation analysis showed that the total scores of AAQ-Ⅱ (21.81 ± 8.23),job burnout (22.71 ± 6.60) and its three dimensions including emotional exhaustion (8.93 ± 2.87),depersonalization (6.64±2.30)as well as reduced personal accomplishment(7.14±2.52) were positively correlated with negative coping dimension of coping style (10.86±4.99) (r=0.324-0.510,all P＜0.01),while negatively correlated with positive coping dimension(26.44±5.86) (r=-0.102--0.143,all P＜0.01).(2) Structural equation model analysis showed that positive and negative coping dimension had partial mediating effects on the relationship between psychological flexibility and job burnout (x2/df=2.30,GFI =0.91,AGFI =0.90,NFI=0.90,IFI=0.93,TLI=0.92,CFI=0.93,RMSEA=0.04).(3) Bootstrap test showed that the mediating effect sizes for positive and negative coping were 3.8％ and 8.9％ respectively and totally mediating effect size of coping style was 12.7％.Psychological flexibility had much larger effects on job burnout,and the direct effect size was 87.3％.Conclusion Coping style plays a mediating role in the relationship between psychological flexibility and job burnout,but its effect is less important.Psychological flexibility plays a major role and more directly influences on job burnout.

Objective To evaluate the performance of Xpert C. difficile multiplex real-time PCR assay for diagnosis of Clostridium difficile infections in Chinese hospital settings. Methods This study was performed in Huashan Hospital, Ruijin Hospital, Beijing Hospital, Nanfang Hospital and Sir Run Run Shaw Hospital using a standard study protocol. Unique unformed stools from patients with acute hospital-acquired diarrhea were simultaneously analyzed by toxigenic anaerobic cultures and the Xpert C. difficile assay. All specimens displaying discordant results between the Xpert assay and toxigenic culture were sent for Sanger tcdB gene sequencing. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), total concordance rate, and 95％ confidence interval (CI) were calculated before and after resolution of discordant results using SAS 9.3. Results A total of 745 stool specimens were collected and 46 were excluded due to failure of C. difficile recovery. The remaining 699 specimens were included. Compared to the results of toxigenic culture, the sensitivity, specificity, PPV, and NPV of Xpert C. difficile assay were 94.1％ (144/153)(95％CI:89.1％-97.3％), 93.2％ (509/546)(95％CI:96.7％-99.2％), 79.6％ (144/181)(95％CI:72.9％-85.2％)and 98.3％ (509 / 518) (95％CI: 96.7％-99.2％), respectively. Both methods had a Kappa of 0.819. Xpert C. difficile assay showed sensitivity of 98.4％(62/63) (95％ CI: 90.3％-99.9％) and specificity of 93.2％(509/546) (95％ CI: 90.8％-95.2％) for toxin A-negative toxin B-positive strains. After the discordant results resolved by tcdB gene sequencing, PCR assay provided better performance with high sensitivity, specificity, positive predictive value, and negative predictive value [98.8％ (171 / 173), 98.1％ (516 / 526), 94.5％ (171/181) and 99.6％ (516/518), respectively]. Conclusions Compared to the results of toxigenic culture, the sensitivity, specificity and NPV of Xpert C. difficile assay were 94.1％ (144/153) and 93.2％(509/546), respectively. With the results available within 1 h, Xpert C. difficile assay provides prompt and precise laboratory diagnosis in Chinese clinical settings.

Myeloid differentiation factor 88 (MyD88) plays an important role in tumorigenesis,development and malignant transformation,also participates in the microenvironment,proliferation,apoptosis,invasion,metastasis and tumor resistance.MyD88 may serve as a new and meaningful therapeutic target,which can promote the growth and development of tumors by regulating multiple signaling pathways and enhance the drug resistance of tumor cells.

Objective To investigate the role of combined analysis of E2F3a and CASP8AP2 expression in prognosis evaluation in pediatric acute lymphoblastic leukemia (ALL). Methods The study included 141 newly diag-nosed pediatric ALL patients enrolled at the Hematology Center,Beijing Children′s Hospital,Capital Medical Universi-ty between March 2008 and July 2010,including 97 boys and 44 girls(aged 1. 2 - 15. 5 years,median 5. 2 years). E2F3a and CASP8AP2 expressions were quantified in 141 children with ALL by adopting real - time quantitative poly-merase chain reaction (qPCR). Receiver operating characteristic (ROC)curve was used to find the best cut - off point to divide the patients into E2F3a or CASP8AP2 low - and high - expression groups,and the treatment outcome between the groups was compared. Cox regression was used to analyze the prognostic significance of the combined expression of E2F3a and CASP8AP2. Results The estimated 5 - year relapse free survival(RFS)rate,event free survival(EFS) rate and overall survival (OS)rate of patients with low - E2F3a and low - CASP8AP2 expression were (58. 9 ± 10. 0)％,(56. 0 ± 9. 9)％ and (72. 0 ± 9. 0)％,respectively. They were significantly lower than those of patients with high - E2F3a and high - CASP8AP2 expression,whose RFS,EFS and OS were (94. 9 ± 2. 5)％,(93. 7 ± 2. 7)％ and (96. 2 ± 2. 2)％,and the differences were all statistically significant(all P < 0. 05),respectively. Compared with other patients,the one with low expression of both E2F3a and CASP8AP2 had a poorer prognosis. In addition to MLL rear-rangements and minimal residual disease level at the end of remission induction,low expression of both E2F3a and CASP8AP2 remained as independent prognostic factors. Conclusion Low expressions of E2F3a and CASP8AP2 pre-dict poor prognosis in pediatric ALL. Combined assessment of E2F3a and CASP8AP2 expression could predict poor prognosis and relapse more accurately.

Objective: To probe into the correlation between chronic liver disease and intestinal barrier function. Methods: 1 491 cases of hospitalized patients were enrolled, of which 741 cases were of chronic liver diseases, including 397 cases of fatty liver diseases, 230 cases of chronic hepatitis, 114 cases of liver cirrhosis, and 750 cases of non-hepatic diseases. All admitted patients’ intestinal barrier function like diamine oxidase (DAO), D-lactate, lipopolysaccharide, and biochemical indicators of liver functions were tested. According to different data, statistical analysis was done using t-test, ANOVA, Dunnett’s test, χ ² test of fourfold table, Pearson’s correlation, and binary logistic regression. Results: The intestinal barrier dysfunction was more likely to occur in the chronic liver disease group than that of non-hepatic disease group [54.15% (379/741) vs. 18.53% (139/750), χ ² = 193.58, P < 0.001]. The correlation analysis between biochemical indicators of liver function and intestinal barrier function in chronic liver disease group showed that alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma glutamyl transferase (GGT), and total bilirubin levels were more susceptible to intestinal barrier dysfunction than those with normal indexes (P < 0.05 ). GGT had stimulated DAO (P < 0.05, OR > 1), D-lactate (P < 0.05, OR > 1), lipopolysaccharide (P < 0.05, OR > 1), ALT and AST. Conclusion Chronic liver disease increases with damage to intestinal barrier function.

Objective To investigate the role of spo0A gene in growth and sporulation of Clostridium difficile clinical isolates. Methods ClosTron gene knock-out system was used to knock out the spo0A gene of C. difficile strain C25. Bacterial growth curve was plotted by measuring D600 with spectrophotometer in different phases of bacterial growth. Malachite green staining technique was used to count the number of vegetative cells and spores under optical microscope. The sporulation rate was calculated. Results The spo0A mutant and its C25 parental strain showed similar patterns of growth. However, after knock-out of spo0A gene, an asporogenous phenotype was built, while the parental strain could produce spores as usual.Conclusions The spo0A gene plays a key role in sporulation but not growth of C. difficile strain.

Objective To investigate the effect of ursolic acid (UA) on the colorectal tumor and microenvironment in mice,and to provide a theoretical basis for the clinical application of UA.Methods The models of subcutaneous transplanted tumor of mouse CT26 cells was established.The models were divided into four groups:control group,tumor bearing group,tumor beating dimethyl sulfoxide (DMSO) group and tumor beating UA group.Tbe serum levels of interleukin-6 (IL-6) were detected by enzyme linked immunosorbent assay (ELISA).The number and percentage of myeloid-derived suppressor cell (MDSC) in the spleen of mice were analyzed by flow cytometry.The mRNA levels of IL-6 and signal transducer and activator of transcription 3 (STAT3) in tumor were examined by real-time quantitative polymerase chain reaction (RT-PCR).The protein levels of STAT3 and p-STAT3 in tumor were detected by Western blotting.Results The results showed that UA could significantly decrease the number of spleen MDSC.The accounts of spleen MDSC of tumor bearing UA group (249.60 ± 17.12) was lower than that of tumor beating DMSO group (366.40 ± 34.08),and the difference was statistically significant (P =0.021).The serum level of IL-6 in tumor bearing UA group [(46.40 ± 17.05) pg/ml] was decreased than that in tumor bearing DMSO group [(94.27 ±21.51) pg/ml],and the difference was statistically significant (P =0.012).The expression levels of IL-6 and STAT3 mRNA in tumor tissues of tumor bearing UA group (0.12 ±0.01,0.21 ±0.08) were lower than those of tumor bearing DMSO group (0.69 ± 0.14,0.79 ± 0.06),and the differences were statistically significant (P =0.008;P =0.003).The protein expression levels of STAT3 and p-STAT3 in tumor tissues of tumor bearing UA group (0.81 ±0.02,0.28 ±0.04) were lower than those of tumor bearing DMS0 group (0.98 ±0.02,0.91 ±0.22),and the differences were statistically significant (P =0.027;P =0.029).Conclusion UA may inhibit the activation of STAT3 signaling pathway and the amplification of MDSC in microenvironment by reducing IL-6,thus to enhance the function of immune-killing tumor cells to regulate tumor immune microenvironment and inhibit the immune escape of mouse colorectal cancer cells.

Objective To analyze the characteristics of the speech fluency of preschool hearing-impaired children with hearing devices ,and to explore influence of different hearing devices, age, ender and intervention time on their speech fluency.Methods A total of 109 subjects of normal children and hearing-impaired children were induded in this study.They were divided into 3 groups, 30 of normal children , 28 of hearing-impaired children with hearing aids , 26 of hearing-impaired children with cochlear implants, 25 of hearing-impaired children with Cochlear implant and hearing aids.Their speech speed,pause,repetition,and prolongation in spontaneous language tasks by exploring the influence of factors such as hearing devices'' types,age, gender and intervention time difference to their speech fluency were studied.Results (1) The speed in normal children was significantly higher than those of in the other three groups(P<0.05), while the normal children had less pauses than the hearing-impaired children with cochlear implants(P=0.001) and hearing-impaired children with cochlear implants and hearing aids(P=0.032).The normal children have less prolongation than the hearing-impaired children with hearing aids (P=0.001) and hearing-impaired children with cochlear implants and hearing aids(P=0.001) but noticeably greater prolongation than the hearing-impaired children with cochlear implants (P<0.001).(2) Hearing-impaired children''s speech speed,pause,repetition,and prolongation had no significant differences in gender(P>0.05).The speech speed of children with hearing aids was higher than children with cochlear implants(P=0.045).Children with cochlear implant had more pauses than children with hearing aids(P=0.028).The speech speed of hearing-impaired children in 3.5~5 years old was lower than hearing-impaired children in 5.1~6.5 years old(P=0.042).The speech speed of hearing-impaired children who receive intervention less than 2.5 years, was higher than the children who receive intervention more than 2.5 years(P=0.002),while children who receive intervention less than 2.5 years had more pauses(P=0.047) and prolongations(P=0.002).Conclusion (1)Preschool hearing-impaired children''s speed is lower than the normal, and the times of pause and prolongation is more than the normal.(2) Different hearing devices and intervention time influence preschool hearing-impaired children''s verbal fluency, while gender have no effects.