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BACKGROUND The present study explored the role and mechanism of microRNA-874-3p (miR-874-3p) in the migration of the osteosarcoma cell line, U-2 OS. METHODS The expression profile of osteosarcoma (OS) microRNA (GSE65071) datasets was downloaded from the Gene Expression Omnibus (GEO) database (https://www.ncbi.nlm.nih.gov/geo) to identify differentially expressed miRNAs in OS and its biological functions. A quantitative reverse transcription-polymerase chain reaction was performed to detect the expression of miR-874-3p and its target gene regulator of G protein 4 (RGS4) in human osteosarcoma cells U-2 OS and normal osteoblast hFOB1.19. Plasmid overexpression miR-874-3p and pcDNA-RGS4 were transfected into U-2 OS using Lipofectamine 2000 (Thermo Fisher, Waltham, MA, USA). Cell migration was measured using Transwell migration assays. Bioinformatic analysis and luciferase reporter assay were conducted to search for the target gene of miR-874-3p. RESULTS In total, 167 differentially expressed miRNAs were detected after the analysis of GSE65071; of which 78 were up-regulated genes and 89 were down-regulated. miR-874-3p was down-regulated and selected for further analysis. The expression level of miR-874-3p in U-2 OS cells was significantly decreased compared to the hFOB1.19 cell line (p < 0.05). Overexpression of miR-874-3p significantly inhibited the proliferation and migration of U-2 OS cells and overexpression of RGS4 reversed the inhibitory effect of miR-874-3p on U-2 OS cells. Through luciferase report analyses and bioinformatic analysis, RGS4 may be the candidate target gene of miR-874-3p. CONCLUSIONS In conclusion, overexpression of miR-874-3p suppressed OS cell proliferation and migration. Thus, miR-874-3p might present a therapeutic agent for the treatment of OS.

Long non-coding RNAs have recently emerged as important regulators in the pathogenesis and progression of cancers. The long non-coding RNA urothelial carcinoma–associated 1 is reportedly upregulated and functions as an oncogene in some tumors. However, the role of urothelial carcinoma–associated 1 in renal cell carcinoma is not well elucidated so far. In this study, we found that urothelial carcinoma–associated 1 was overexpressed in renal cell carcinoma tissues compared with the adjacent normal tissues, and higher urothelial carcinoma–associated 1 expression levels were positively associated with advanced tumor stage and poor survival time in renal cell carcinoma patients. Further studies showed that knockdown of urothelial carcinoma–associated 1 suppressed renal cell carcinoma cell proliferation and S-phase cell number in vitro. Moreover, urothelial carcinoma–associated 1 was found to be associated with enhancer of zeste homolog 2, which suppressed p21 expression through histone methylation (H3K27me3) on p21 promoter. We also showed that knockdown of urothelial carcinoma–associated 1 increased the p21 protein expression through regulating enhancer of zeste homolog 2. In addition, bioinformatics analysis and dual-luciferase reporter assays confirmed that miR-495 was a target of urothelial carcinoma–associated 1 in renal cell carcinoma, and urothelial carcinoma–associated 1 promoted cell proliferation by negatively regulating miR-495. These findings illuminated that urothelial carcinoma–associated 1 promoted renal cell carcinoma progression through enhancer of zeste homolog 2 and interacted with miR-495. Overall, overexpression of urothelial carcinoma–associated 1 functions as an oncogene in renal cell carcinoma that may offer a novel therapeutic target for renal cell carcinoma patients.

Layered rare-earth hydroxide nanosheets (3-8 nm thick) of Y2(OH)5NO3·nH2O (NO3--LYH) were successfully synthesized in one step via chemical precipitation at ~4 °C and pH ~8, using yttrium nitrate and ammonium hydroxide as reagents. The interlayer NO3- was found to be free ions and can be completely replaced with SO42- to yield Y2(OH)5(SO4)0.5·nH2O (SO42--LYH). Thermal decomposition behavior of the SO42--LYH was studied in detail, and the phase and morphology evolutions upon calcination in the temperature range 500-1100 °C were also investigated. Characterizations via XRD, FE-SEM, TEM, and FT-IR found that anion exchange did not bring about any appreciable change to the 2-dimensional crystallite morphology but the basal spacing of the crystal structure shrank from ~0.884 to 0.840 nm owing to the indirect coordination of SO42- to the Y3+ ions. DTA/TG and XRD analysis found that the NO3--LYH converts to Y2O3 at ~600 °C, but the SO42--LYH decomposes to oxide at a higher temperature of ~1000 °C via monoclinic Y2O2SO4 in the range of 800-900 °C. The resultant Y2O3 particles have an average size of ~60 nm.

A hybrid power quality compensator (HPQC) is proposed in this paper for comprehensive compensation under minimum dc operation voltage in high-speed traction power supplies. Reduction in HPQC operation voltage can lead to a decrease in the compensation device capacity, power consumptions, and installation cost. The parameter design procedures for minimum dc voltage operation of HPQC are being explored. It is shown through simulation results that similar compensation performances can be provided by the proposed HPQC with reduced dc-link voltage level compared to the conventional railway power compensator. The system rating can thus be reduced. It is also verified that HPQC would operate at the minimum dc voltage with the proposed parameter design via simulations. A hardware prototype is constructed and the experimental results show that through the proposed design, HPQC is able to provide system unbalance, reactive power, and harmonic compensation in cophase traction power with reduced operation voltage. The cophase traction power supply with proposed HPQC is suitable for high-speed traction applications.

Most control algorithm for Railway Static Power Conditioner (RPC) is developed based on full compensation requirement and has no relationship with power quality standards. There are actually tolerances in power quality that full compensation may not be required. However, the relationship between RPC compensation and power quality standard is complicated and less study has been done. In this paper, the relationship between RPC compensation and power quality standard is being modeled. This makes RPC compensation more flexible so as to reduce the compensation capacity and cost. Simulation verifications are done using the electromagnetic power transient software PSCAD®/EMTDC™.

Characteristics of anaerobic granules before and after acclimation, removal efficiencies of 3-nitrophenol (3-NP) and performance of 3-NP wastewater treatment were investigated in a lab-scale upflow anaerobic sludge bed (UASB). The results showed that granular sludge acclimatized to 3-NP rapidly during acclimation. Using SEM, the filamentous bacteria was the predominant bacteria on the surface of granules. Throughout the study of 3-NP wastewater anaerobic degradation, hydraulic retention time (HRT) and input COD concentration were kept constant as 26 h and 2 500 mg/L, respectively. While 3-NP concentrations increasing from 20 mg/L to 250 mg/L gradually, COD removal decreased from 95.2% to 85.1% and 3-NP removal efficiencies were always more than 99%. 3-AP was found to be the major intermediate during the degradation of 3-NP. Out of the total input of 3-NP concentration, on molar basis, about 58.7% - 111.9% of 3-NP was recovered in the form of 3-AP. With increasing 3-NP concentration, the variations of gas production were minimal. The minimum methane percentage was 65% and the maximum was 74%.