Poly(A)-specific ribonuclease protein promotes the proliferation,invasion and migration of esophageal cancer cells

BACKGROUND Bioinformatics analysis showed that the expression of the poly(A)-specific ribonuclease(PARN)gene in gastric cancer,head and neck squamous cell carcinoma,melanoma,cervical cancer and lung squamous cell carcinoma tissues was significantly higher than that in normal tissues and was associated with high stage and poor prognosis.The expression of the PARN gene in esophageal cancer(EC)tissue is also significantly higher than that in normal tissues,but the effect of PARN on the proliferation,migration and invasion of EC cells remains unclear.AIM To investigate the relationship between PARN and the proliferation,migration and invasion of EC cells.METHODS The EC tissues of 91 patients after EC surgery and 63 paired precancerous healthy tissues were collected.PARN mRNA levels were measured using a tissue microarray,and the PARN expression level was evaluated using immunohistochemistry to analyze the relationship between PARN expression and clinicopathologic features as well as the survival and prognosis of patients.In addition,the effects of PARN gene knockout on tumor cell proliferation,invasion and migration were studied by using shRNA during the in vitro culture of EC cell lines Eca-109 and TE-1,and the effects of the PARN gene on tumor growth in vivo were verified by a xenotransplantation nude mice model.RESULTS The expression of PARN in EC tissues was higher than that in adjacent normal tissues,and the level of PARN expression was significantly positively correlated with lymphatic metastasis.Patients with high PARN levels had poor overall survival.BIM,IGFBP-5 and p21 levels were significantly increased in the PARN knockout group,while the expression levels of the antiapoptotic proteins Survivin and sTNF-R1 were significantly decreased in the apoptotic antibody array data.In addition,the expression levels of Akt,p-Akt,PIK3CA and CCND1 in the downstream signaling pathway regulating EC progression were significantly decreased.The culture of EC cell lines confirmed that the apoptosis rate of EC cells was significantly increased,the growth and proliferation of tumor cells were significantly inhibited,and the invasion and migration ability of tumor cells were significantly decreased after PARN gene knockout.In vivo experiments of BALB/c nude mice transfected with Eca-109 cells expressing control shRNA(sh-NC)and PARN shRNA(sh-PARN)showed that the tumor volume and weight of nude mice treated with sh-PARN were significantly decreased compared with those of nude mice treated with sh-NC,indicating that PARN knockdown significantly inhibited tumor growth in vivo.CONCLUSION PARN has antiapoptotic effects on EC cells and promotes their proliferation,invasion and migration,which is associated with the development of EC and poor patient prognosis.PARN may become a potential target for the diagnosis,prognosis prediction and treatment of EC.

Rosiglitazone prevents murine hepatic fibrosis induced by Schistosoma japonicum

AIM: To evaluate the effect of rosiglitazone in a murine model of liver fibrosis induced by Schistosoma japonicum infection. METHODS: A total of 50 mice were randomly and averagely divided into groups A, B, C, D and E. The mice in group A served as normal controls, while those in the other four groups were infected with Schistosoma japonicum to induce the model of liver fibrosis. Besides, the mice in groups C, D and E were treated with praziquantel, rosiglitazone and praziquantel plus rosiglitazone, respectively. NF-κB binding activity and expression of PPARγ-mRNA were determined by Western blot assay and real-time quantitative PCR. Radioimmunonassay technique was used to detect the serum content changes of TNF-α and IL-6. Histological specimens were stained with HE. Expression of TGF-β1, a-smooth muscle actin and type ?Ⅰ?and type Ⅲ collagen was detected by immunohistochemistry and multimedia color pathographic analysis system. RESULTS: Inflammation and fibrosis in the rosiglitazone plus praziquantel treatment group (group E) were lightest among the mice infected with Schistosoma (P < 0.05). To further explore the mechanism of rosiglitazone action, we found that rosiglitazone can significantly increase the expression of PPARγ [E: -18.212 ± (-3.909) vs B: -27.315 ± (-6.348) and C: -25.647 ± (-5.694), P < 0.05],reduce the NF-κB binding activity (E: 88.89 ± 19.34 vs B: 141.11 ± 15.37, C: 112.89 ± 20.17 and D: 108.89 ± 20.47, P < 0.05), and lower the serum level of TNF-α (E: 1.613 ± 0.420 ng/mL vs B: 2.892 ± 0.587 ng/mL, C: 2.346 ± 0.371 ng/mL and D: 2.160 ± 0.395 ng/mL, P < 0.05) and IL-6 (E: 0.106 ± 0.021 ng/mL vs B: 0.140 ± 0.031 ng/mL and C: 0.137 ± 0.027 ng/mL, P < 0.05) in mice with liver fibrosis. Rosiglitazone can also substantially reduce the hepatic expression of TGF-β1, α-SMA type Ⅰand type Ⅲ collagen in mice with liver fibrosis. CONCLUSION: The activation of PPARγ by its ligand can retard liver fibrosis and suggest the use of rosiglitazone for the treatment of liver fibrosis due to Schistosoma japonicum infection.

In-depth analysis of the fatigue mechanism induced by inclusions for high-strength bearing steels

A numerical study of stress distribution and fatigue behavior in terms of the effect of voids adjacent to inclusions was conducted with finite element modeling simulations under different assumptions.Fatigue mechanisms were also analyzed accordingly.The results showed that the effects of inclusions on fatigue life will distinctly decrease if the mechanical properties are close to those of the steel matrix.For the inclusions,which are tightly bonded with the steel matrix,when the Young’s modulus is larger than that of the steel matrix,the stress will concentrate inside the inclusion;otherwise,the stress will concentrate in the steel matrix.If voids exist on the interface between inclusions and the steel matrix,their effects on the fatigue process differ with their positions relative to the inclusions.The void on one side of an inclusion perpendicular to the fatigue loading direction will aggravate the effect of inclusions on fatigue behavior and lead to a sharp stress concentration.The void on the top of inclusion along the fatigue loading direction will accelerate the debonding between the inclusion and steel matrix.

Stress-state dependence of dynamic strain aging:Thermal hardening and blue brittleness

This study aims to discover the stress-state dependence of the dynamic strain aging(DSA)effect on the deformation and fracture behavior of high-strength dual-phase(DP)steel at different deformation temperatures(25-400°C)and reveal the damage mechanisms under these various configurations.To achieve different stress states,predesigned specimens with different geometric features were used.Scanning electron microscopy was applied to analyze the fracture modes(e.g.,dimple or shear mode)and underlying damage mechanism of the investigated material.DSA is present in this DP steel,showing the Portevin-Le Chatelier(PLC)effect with serrated flow behavior,thermal hardening,and blue brittleness phenomena.Results show that the stress state contributes distinctly to the DSA effect in terms of the magnitude of thermal hardening and the pattern of blue brittleness.Either low stress triaxiality or Lode angle parameter promotes DSA-induced blue brittleness.Accordingly,the damage mechanisms also show dependence on the stress states in conjunction with the DSA effect.

Trial characteristics and treatment effect estimates in randomized controlled trials of Chinese herbal medicine: A meta-epidemiological study

Background:Previously published meta-epidemiological studies focused on Western medicine have identified some trial characteristics that impact the treatment effect of randomized controlled trials(RCTs).Nevertheless,it remains unclear if similar associations exist in RCTs on Chinese herbal medicine(CHM).Further,Chinese medicine-related characteristics have not been explored yet.Objective:To investigate trial characteristics related to treatment effect estimates on CHM RCTs.Search strategy:This meta-epidemiological study searched 5 databases for systematic reviews on CHM treatment published between January 2011 and July 2021.Inclusion criteria:An eligible systematic review should only include RCTs of CHM and conduct at least one meta-analysis.Data extraction and analysis:Two reviewers independently conducted data extraction on general characteristics of systematic reviews,meta-analyses and included RCTs.They also assessed the risk of bias of RCTs using the Cochrane risk of bias tool.A two-step approach was used for data analyses.The ratio of odds ratios(ROR) and difference in standardized mean differences (dSMD) with 95%confidence interval (CI) were applied to present the difference in effect estimates for binary and continuous outcomes,respectively.Results:Ninety-one systematic reviews,comprising 1338 RCTs were identified.For binary outcomes,RCTs incorporated with syndrome differentiation (ROR:1.23;95%CI:[1.07,1.39]),adopting Chinese medicine formula (ROR:1.19;95%CI:[1.03,1.34]),with low risk of bias on incomplete outcome data (ROR:1.29;95%CI:[1.06,1.52]) and selective outcome reporting (ROR:1.12;95%CI:[1.01,1.24]),as well as a trial size≥100 (ROR:1.23;95%CI:[1.04,1.42]) preferred to show larger effect estimates.As for continuous outcomes,RCTs with Chinese medicine diagnostic criteria (dSMD:0.23;95%CI:[0.06,0.41]),judged as high/unclear risk of bias on allocation concealment (dSMD:-0.70;95%CI:[-0.99,-0.42]),with low risk of bias on incomplete outcome data (dSMD:0.30;95%CI:[0.18,0.43]),conducted at a single center (dSMD:-0.33;95%CI:[-0.61,-0.05]),not using intention-to-treat analysis (dSMD:-0.75;95%CI:[-1.43,-0.07]),and without funding support (dSMD:-0.22;95%CI:[-0.41,-0.02]) tended to show larger effect estimates.Conclusion:This study provides empirical evidence for the development of a specific critical appraisal tool for risk of bias assessments on CHM RCTs.

Optical properties of＇ Au-core Pt-shell nanorods studied using FDTD simulations

Au-core/Pt-shell nanorods （Au@Pt NRs） have been prepared by a Au nanorod-mediated growth method, and they exhibit high electromagnetic field enhancements under coupling conditions. Boosted by a long-range effect of the high electromagnetic field generated by the Au core, the electromagnetic field enhancement can be controlled by changing the morphology of the nanostruc- tures. In this study, we report the results on the simulations of the electromagnetic field enhancement using a finite difference time domain （FDTD） method, taking the real shapes of the Au@Pt NRs into account. Due to the ＂hot spot＂ effect, the electromagnetic field can be localized between the Pt nanodots. The electromagnetic field enhancement is found to be rather independent of the Pt con- tent, whereas the local roughness and small sharp features might significantly modify the near-field. As the electromagnetic field enhancement can be tuned by the distribution of Pt nanodots over the Au-core, Au@Pt NRs can find potential applications in related areas.