Circular RNA UBAP2 contributes to tumor growth and metastasis of cervical cancer via modulating miR-361-3p/SOX4 axis.

BACKGROUND: Increasing researches have reported that circular RNA UBAP2 (circUBAP2) may be a potential prognosis biomarker and participate in the development of several cancers; however, the role of circUBAP2 in cervical cancer (CC) remains largely unclear. METHODS: We applied qRT-PCR and Western blot to examine expression levels of circUBAP2, miR-361-3p, SOX4, Bax, Bcl-2, Cleaved caspase 3, N-cadherin, Vimentin and E-cadherin. Cell proliferation, apoptosis, invasion and migration were analyzed by MTT assay, Flow cytometry, and Transwell assay, respectively. The interaction between miR-361-3p and circUBAP2 or SOX4 was confirmed by luciferase reporter assay and pull-down assay. Murine xenograft model was established by injecting SiHa cells which stably transfected sh-circUBAP2. RESULTS: CircUBAP2 was up-regulated in CC tissues and cell lines and high circUBAP2 expression predicated poor outcome. Knockdown of circUBAP2 suppressed cell proliferation, migration, invasion and EMT, while induced apoptosis in CC in vitro, and inhibited tumor growth and metastasis in vivo. MiR-361-3p directly bound to circUBAP2 or SOX4, and circUBAP2 could regulate SOX4 expression by sponging miR-361-3p in CC cells. Furthermore, rescue assay results demonstrated that the inhibitory effects of circUBAP2 knockdown on cell growth and metastasis were partially reversed by miR-361-3p down-regulation or SOX4 up-regulation in CC. CONCLUSION: CircUBAP2 represents a prognostic marker and contributes to tumor growth and metastasis via modulating miR-361-3p/SOX4 axis in CC, which indicates a potential therapeutic target for CC treatment.

Enantioselective organocatalytic oxa-Michael addition of oximes to ß-CF3-ß-disubstituted nitroalkenes: efficient synthesis of ß-amino-α-trifluoromethyl alcohols.

An enantioselective oxa-Michael addition of oximes to ß-CF3-ß-disubstituted nitroalkenes catalyzed by a chiral bifunctional cinchona alkaloid-based thiourea has been developed. A variety of trifluoromethylated oxime ethers possessing a tetrasubstituted carbon stereocenter were obtained in good yields with high enantioselectivities.

Photocatalytic generation of N-centered hydrazonyl radicals: a strategy for hydroamination of ß,γ-unsaturated hydrazones.

A visible-light photocatalytic generation of N-centered hydrazonyl radicals has been accomplished for the first time. This approach allows efficient intramolecular addition of hydrazonyl radical to terminal alkenes, thus providing hydroamination and oxyamination products in good yields. Importantly, the protocol involves deprotonation of an N-H bond and photocatalytic oxidation to an N-centered radical, thus obviating the need to prepare photolabile amine precursors or the stoichiometric use of oxidizing reagents.

Modelling of soil environmental quality and early warning of integrated ecological risk.

The knowledge of dynamic trend in soil heavy metal contamination and associated risk is important for soil pollution prevention, safe utilization and early warning of soil environmental quality and ecological risk. In this study, a modified integrated risk index (NIRI) was adopted to evaluate ecological risk in agricultural soil in Wenzhou with 70 samples, which is located in the southeast of China. In addition, two scenarios with different metal fluxes (optimistic and default scenario) were constructed to predict future dynamic trend of metal concentrations. Results showed the agricultural soil was mainly contaminated by Cd and Pb. The NIRI indicated moderate to considerable risk in most sites and Cd posed the greatest contribution to NIRI value. Besides, higher risk was determined in paddy soil than that in vegetable. Scenario simulation results revealed general declining trend in optimistic scenario while increasing trend in default scenario for metal concentration. However, exceedance varied with prediction period, soil types and metals. Ecological risk probability showed similar trend with metal concentration, indicating significant shift to higher risk level in default scenario while insignificant decrease in optimistic scenario. The proposed scenario simulation results provide reference to support soil quality improvement and risk management.

Insight into the performance and mechanism of persimmon tannin functionalized waste paper for U(VI) and Cr(VI) removal.

Herein, using dialdehyde waste paper (DAWP) as a cross-linking agent to immobilize persimmon tannin (PT) was first used to remove the U(VI) and Cr(VI) via the "waste control by waste" concept. The microscopic and macroscopic surface properties of the as-prepared adsorbent was characterized by the advanced characterization techniques. Factors that affected the elimination process such as variable pH, coexistence ions and equilibrium time were investigated by batch techniques. The results showed that the maximal removal capacities of U(VI) and Cr(VI) on DAWP-PT were 242.3 mg/g (pH = 6.0) and 178.7 mg/g (pH = 2.0) at 298 K, which exhibited competitiveness with most of the reported solid materials. Meanwhile, adsorption data were fitted perfectly to the Langmuir and Pseudo-second-order equations, which indicated that the monolayer and homogenous chemisorption dominated the removal process. The SEM-EDX, DFT and XPS analysis conformed that adsorption of U(VI) was mainly via surface complexation, while the elimination of Cr(VI) was a redox reaction process, and about 65.33% of Cr(III) and 34.67% of Cr(VI) co-existed onto the surface of DAWP-PT. Thus, this study would provide a high-efficiency and low-cost adsorbent for radionuclide and heavy metal treatment.

Magnetic MXene-NH2 decorated with persimmon tannin for highly efficient elimination of U(VI) and Cr(VI) from aquatic environment.

Herein, a magnetic MXenes based composite (Fe3O4@Ti3C2-NH2-PT) was constructed by loading Fe3O4 nano-particles into the interlamellar spacing of persimmon tannin-functionalized Ti3C2-NH2. The structure, morphology and physicochemical properties of the as-prepared adsorbents were probed by advanced spectroscopy techniques, while the impact of various experimental conditions like pH values, amount of adsorbent and contact time on the removal trend were examined by batch experiments. The elimination results revealed that Fe3O4@Ti3C2-NH2-PT could be applied in a wide range of initial concentrations, and exhibited outstanding removal efficiency for U(VI) (104.9 mg/g, pH = 5.0) and Cr(VI) (83.8 mg/g, pH = 2.0). Meanwhile, the adsorption process was described well with the Langmuir isotherm and Pseudo-second-order kinetics models, which indicated that the monolayer chemical adsorption occurred during elimination of the two contaminants. The spectral analysis results manifested that elimination of U(VI) followed an inner-sphere configuration, whereas uptake of Cr(VI) was determined by electrostatic interaction and adsorption-reduction process. This work opened a new opportunity in designing MXenes based adsorbents in the application for environmental remediation.

Development and characterization of chitosan functionalized dialdehyde viscose fiber for adsorption of Au(III) and Pd(II).

A highly efficient fiber-based adsorbent (DAVFs-CS) was developed via decoration of chitosan (CS) on the dialdehyde viscose fibers (DAVFs) substrate, and employed to selective separation of precious metals from simulated contaminated water. The surface functionalization of the solid material was probed using the Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS), Thermogravimetric analysis (TGA) and nuclear magnetic resonance (NMR) technique. The batch characteristic results showed that the maximum uptake capacities of DAVFs-CS were higher up to 322 mg/g and 207 mg/g for Au(III) and Pd(II) at optimal pH 2.0 and 3.0, which exhibited competitiveness with the majority of the reported adsorbents. Meanwhile, the adsorption data were in accordance with Langmuir and PSO equations, which indicated that the monolayer chemisorption dominated the adsorption process. The competitive adsorption study showed that the removal efficiency of Au(III) was not susceptible to the co-existing impurities. Adsorption mechanism study revealed that the negative Au(III) or Pd(II) species were firstly adsorbed on DAVFs-CS via the protonated amino groups, subsequently the partially reduction of them to zero-valent gold and palladium with the help of reductive functional groups. Thus, DAVFs-CS could be as a promising adsorbent to recovery of precious metals owning to its unique adsorption mechanism and excellent adsorption performance.

Persimmon tannin functionalized polyacrylonitrile fiber for highly efficient and selective recovery of Au(III) from aqueous solution.

An efficient fibrous adsorbent (PANF-TETA-PT) was prepared via grafting triethylenetetramine (TETA) on polyacrylonitrile fiber (PANF), followed by persimmon tannin (PT) immobilizing. Detailed characterization certified that plenty amounts of amino and phenolic hydroxyl groups existed on the surface of PANF-TETA-PT, which would provide excellent active sites for Au(III) adsorption. The batch characteristic results found that the adsorption equilibrium data could be fitted well with Langmuir equation, while the obtained kinetic data were consistent with the Pseudo-second-order equation. The maximum equilibrium adsorption capacity of PANF-TETA-PT towards Au(III) (801.2 mg/g) was apparently superior than that of the reported adsorbents, and the competitive adsorption showed that PANF-TETA-PT had a good preference to adsorption Au(III) in spite of some coexisting pollutants. The characterization analysis of Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and X-ray diffractometer spectrum (XRD) revealed that the electrostatic attraction and chelation dominated the uptake of Au(III) on PANF-TETA-PT, in which a part of loaded Au(III) was reduced to Au particles with the help of reductive functional groups. Thus, this adsorbent could be as a promising candidate to separation and preconcentration of Au(III) from wastewater.

Adsorption and reduction of Cr(VI) from aqueous solution using cost-effective caffeic acid functionalized corn starch.

Herein, a potential bio-adsorbent (DACS-CA) was formed via immobilizing caffeic acid (CA) on dialdehyde corn starch (DACS) for Cr(VI) removal. The characterization techniques such as IR, Raman, XPS and 13C NMR were performed to analyze surface elements and functional groups on the as-prepared sorbents. Batch experiments revealed that the maximum Cr(VI) removal amount (96.45 mg/g) took place at a pH value of 3.0, adsorption temperatures of 333 K and solid-liquid ratio of 0.2. The isotherms studies found that the Cr(VI) removal of DACS-CA was monolayer adsorption, while the kinetics analysis revealed that chemisorption was the main power for removal process. Characterization analysis found that about Cr(VI) (53.02%) and Cr(III) (46.98%) species co-existed onto the surface of DACS-CA, which implied that a redox reaction may be occurred between Cr(VI) and the bio-adsorbent. Namely, Cr(VI) was first loaded on DACS-CA via electrostatic interaction, subsequently Cr(VI) was partially transformed into Cr(III) by reductive functional groups, meanwhile the resulting Cr(III) was immobilized by the carboxyl groups of DACS-CA. Thus, this bio-adsorbent could serve as an efficient sorbent for the removal of Cr(VI) from wastewater in environmental pollution cleanup.

YY1 Promotes Telomerase Activity and Laryngeal Squamous Cell Carcinoma Progression Through Impairment of GAS5-Mediated p53 Stability.

Yin Yang 1 (YY1) is a key transcription factor that exerts functional roles in the cell biological process of various cancers. The current study aimed to elucidate the role and mechanism of YY1 in laryngeal squamous cell carcinoma (LSCC). YY1 mRNA and protein expression in human LSCC cell lines was detected by RT-qPCR and Western blot analysis. An interaction of YY1, GAS5, and p53 protein stability was predicted and confirmed by bioinformatics, ChIP, Co-IP, RIP, and FISH assays. Following loss- and gain-function assays, LSCC cell proliferation, colony formation, cell cycle, telomere length and telomerase activity were evaluated by CCK-8 assay, colony formation assay, flow cytometry, and PCR-ELISA, respectively. Nude mice were xenografted with the tumor in vivo. LSCC cell lines presented with upregulated expression of YY1, downregulated GAS5 expression, and decreased p53 stability. YY1 inhibited the expression of GAS5, which in turn recruited p300 and bound to p53, thus stabilizing it. Moreover, YY1 could directly interact with p300 and suppressp53 stability, leading to enhancement of cell proliferation, telomere length and telomerase activity in vitro along with tumor growth in vivo. Collectively, YY1 can stimulate proliferation and telomerase activity of LSCC cells through suppression of GAS5-dependent p53 stabilization or by decreasing p53 stability via a direct interaction with p300, suggesting that YY1 presents a therapeutic target as a potential oncogene in LSCC development and progression.

Ambient BTX measurements in Suzhou, China.

Within the Sino-Italian environmental protection cooperation framework established in 2002, a comprehensive air quality monitoring network has been developed in urban Suzhou, a medium-sized Chinese city, in compliance with European standards (Directive 96/62/EC). This paper is among the first attempts to present a systematic and scientific analysis of benzene, toluene, and xylenes (BTX) pollution in China. It presents our analysis of BTX space-related and time-related measurement results. Background BTX concentrations were investigated by passive sampler Analyst(R) in 2003. We depicted the spatial distribution of average BTX concentrations collected from three 15-day campaigns on isoconcentration maps. This is the first time such detailed BTX concentration maps have been developed in China in a city scale. Continuous measurement of BTX by automatic gas chromatography was carried out at two fixed monitoring stations, one in an urban residential zone and one in a heavy traffic zone, from April to December 2005. The results show similar seasonal trends at both sites, the similarities reaching their greatest level in December and their lowest level in August. The average daily profile of BTX shows greater fluctuation in spring and winter with clear morning and evening peaks. Daily average benzene, toluene, and m,p-xylenes concentrations for the study period were 2.64, 11.52, and 3.52 microg m(-3), respectively. The benzene/toluene ratio we found was lower in Suzhou than those published in studies of other worldwide cities, which indicates serious levels of toluene pollution from local stationary sources. The similarities in seasonal trend and spatial distribution in these manual and automatic measurement results were compared with each other, though the concentration values differed.

Adsorption behavior of Au(III) and Pd(II) on persimmon tannin functionalized viscose fiber and the mechanism.

A novel bio-adsorbent (DAVF-PT) was prepared by the introduction of persimmon tannin (PT) on the surface of viscose fiber (VF) through condensation reaction. The adsorbent was applied to the adsorption of Au(III) and Pd(II) from aqueous solution. Batch adsorption experiment found that the adsorption performance of DAVF-PT for Au(III) and Pd(II) was closely related to pH of solution, initial metal ion concentration as well as co-existing metal ions. The adsorption isotherms data of Au(III) and Pd(II) on DAVF-PT could be best explained by the Langmuir equation, and the fitted maximum adsorption amounts for Au(III) and Pd(II) were 535 mg/g and 214 mg/g, much higher than those similar adsorbents reported in the literatures. The thermodynamic study revealed that adsorption reaction was an endothermic, spontaneous and entropy increase process. Furthermore, the kinetics data of Au(III) and Pd(II) adsorption on DAVF-PT obeyed the Pseudo-second-order equation, indicating that the chemical adsorption was the mainly rate-limiting step. The EDS, XPS and XPD analysis confirmed that the gold and palladium ions were reduced to metallic state following adsorption, while the phenolic group was simultaneously converted into quinone group, indicating the potential use of this novel fiber-based adsorbent in the recovery of precious metal ions from wastewater.

Adsorptive recovery of Au(III) from aqueous solution using crosslinked polyethyleneimine resins.

Resin adsorption is considered as a promising method to recover gold ions from wastewater, but further reduction reaction is required to convert gold ions into particles. In this study, a crosslinked polyethyleneimine resin (CPEIR) was developed via a suspension polymerization of polyethyleneimine (PEI) and ethylene glycol diglycidyl ether (EGDE) for gold recovery. The Au(III) adsorption capacities of CPEIR were significantly impacted by solution pH and initial Au(III) concentrations but unaffected by co-existing metal ions. Compared with commercial anion-exchange resin IRA400, the CPEIR exhibited higher sorption amount and selectivity for Au(III) due to its high density of amine and hydroxyl groups on the surfaces. The adsorption isotherm of Au(III) on CPEIR was well described by the Langmuir equation, and the maximum uptake amount of Au(III) was high up to 943.5 mg/g, much higher than the reported sorbents. The adsorption kinetic data on the CPEIR were fitted well by the Pseudo-second-order equation, and the intraparticle diffusion was found to be the rate-controlling process of Au(III) adsorption. X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) analysis confirmed that Au(III) ions were adsorbed on the CPEIR via electrostatic attraction and chelating interaction, and subsequently the partial loaded Au(III) ions were reduced to elemental gold whereas the hydroxyl groups of CPEIR were oxidized to carbonyl groups.

Adsorption behavior and mechanism of Au(III) on caffeic acid functionalized viscose staple fibers.

A novel fibrous adsorbent (DAVSF-CA) was synthesized via grafting caffeic acid (CA) onto dialdehyde viscose staple fiber (DAVSF), and used to selectively adsorb Au(III) from simulated wastewater. Fourier Transform Infrared (FTIR), X-ray Photoelectron (XPS) and Nuclear Magnetic Resonance (NMR) spectra confirmed that caffeic acid was successfully grafted on DAVSF through condensation reaction. Adsorption experiments revealed that the adsorption of Au(III) on DAVSF-CA was extremely dependent on pH values and temperatures, and the maximum adsorption capacity of 3.71 mmol/g for Au(III) was obtained at pH 3.0 and 333 K according to the Langmuir fitting. High temperature was favorable for Au(III) adsorption because the adsorption of Au(III) on the DAVSF-CA was endothermic. The competitive adsorption demonstrated that DAVSF-CA had a good preference to Au(III) adsorption in the presence of some coexisting pollutants. The adsorption isotherm data of Au(III) were well-described by the Langmuir model, while the kinetic data were fitted well by the Pseudo-second-order equation. The major reaction involving the reduction of Au(III) to Au(0) was identified by XPS and XRD analysis. Namely, Au(III) was first captured on protonated functional groups via electrostatic adsorption, and then reduced to its elemental form and formed the nano-particles on the adsorbent surfaces.

Synthesis of porous polymer based solid amine adsorbent: Effect of pore size and amine loading on CO2 adsorption.

A series of porous polymers was synthesized by a suspension polymerization of divinylbenzene (DVB) and ethylene glycol dimethyl acrylate (EGDMA), which was further functionalized with polyethyleneimine (PEI) for CO2 capture. The results showed that the synthesized DVB and EGDMA (DE) copolymers were an effective support for loading PEI because of its larger pore size and specific surfaces area. It was found that DE (30, 10) loaded with 30wt% PEI exhibited a higher CO2 adsorption amount of 3.28mmol/g at 25°C under dry condition. The CO2 adsorption capacity would decline gradually as the temperature continuously raised, for the reaction between CO2 and amine groups was an exothermic reaction. The kinetics study showed that Avrami kinetic model could accurately describe the whole CO2 adsorption process, suggesting that both physical adsorption and chemical adsorption were involved with the CO2 adsorption process. The intraparticle diffusion and Boyd's film diffusion models were applied to investigate the CO2 diffusion mechanism, the intraparticle diffusion model could well distinguish the rate-limiting step during CO2 adsorption process. This solid amine adsorbent could be regenerated with nitrogen stream at 75°C, and it kept stable CO2 adsorption capacity after eight adsorption-desorption cycles. All these features indicated that this porous polymer based adsorbent has a high potential for CO2 capture and separation from flue gas.

Biosorption of palladium(II) from aqueous solution by grafting chitosan on persimmon tannin extract.

A low-cost and environmentally green biosorbent (PTCS) was prepared by grafting chitosan onto persimmon tannin extract and its potentiality for efficient adsorption of palladium ion (Pd(II)) from aqueous solution was evaluated. Various adsorption parameters such as pH, the initial Pd(II) concentration and temperature were investigated. The maximum adsorption capacity reached 330mg/g at 323K and pH 5.0 when the initial Pd(II) concentration was 100mg/L. The equilibrium adsorption data were satisfactorily fitted with Freundlich isotherm model and biosorption kinetics was found to be in good agreement with pseudo-second-order kinetics model. Thermodynamic calculations indicated that the adsorption process was endothermic and spontaneous in nature because of the negative value of free energy change (ΔG) and positive value of enthalpy change (ΔH). The positive value of entropy change (ΔS) revealed the increased randomness at the solid-liquid interface. FT-IR and XRD analysis verified that Pd(II) adsorption on PTCS was electrostatic interaction and redox reaction. Moreover, selective adsorption study revealed that the adsorbent exhibited good adsorption ability to Pd(II) in the mixture metal ions solutions. All these results indicated that the PTCS biosorbent could be used as a low-cost alternative for the adsorption of Pd(II) in waste-water treatment.

Three-component coupling reaction triggered by insertion of arynes into the S═O bond of DMSO.

An unprecedented three-component coupling reaction of arynes, α-bromo carbonyl compounds, and DMSO triggered by insertion of arynes into the S═O bond of DMSO has been developed. The reaction can generate a wide range of multisubstituted aryl methyl thioethers in good yields, wherein DMSO serves as both methylthiolation reagent and oxygen source.

Sulforaphane inhibits the proliferation of the BIU87 bladder cancer cell line via IGFBP-3 elevation.

AIM: To investigate effects of sulforaphane on the BIU87 cell line and underlying mechanisms involving IGFBP-3. METHODS: Both BIU87 and IGFBP-3-silenced BIU87 cells were treated with sulforaphane. Cell proliferation was detected by MTT assay. Cell cycle and apoptosis were determined via flow cytometry. Quantitative polymerase chain reaction and Western blotting were applied to analyze the expression of IGFBP-3 and NF-κB at both mRNA and protein levels. RESULTS: Sulforaphane (80 µM) treatment could inhibit cell proliferation, inducing apoptosis and cell cycle arrest at G2/M phase. All these effects could be antagonized by IGFBP-3 silencing. Furthermore, sulforaphane (80 µM) could down-regulate NF-κB expression while elevating that of IGFBP-3. CONCLUSIONS: Sulforaphane could suppress the proliferation of BIU87 cells via enhancing IGFBP-3 expression, which negatively regulating the NF-κB signaling pathway.

[Application research of data assimilation in air pollution numerical prediction].

Based on an air pollution modeling system coupling with the non-hydrostatic fifth generation mesoscale meteorological model (MM5) and the regional modeling system for aerosols and deposition (REMSAD), the forecast results of NOx and SO2 in August and September 2002 in Nanjing were assimilated with the optimal interpolation method and the ensemble Kalman filter. The results show that the improvement rates of deviation mean value of NOx and SO2 after assimilated with the optimal interpolation method are 34.20% and 47.53%, and the improvement rates of root mean square errors are 31.95% and 42.04% respectively. It is also demonstrated that the improvement rates of deviation mean value of NOx and SO2 after assimilated with the ensemble Kalman filter with 30 ensemble members are 26.73% and 60.75%, and the improvement rates of root mean square errors are 25.20% and 55.16% respectively. So, the optimal interpolation method and the ensemble Kalman filter both can improve the quality of the initial state from the air pollution numerical prediction model. The comparative experiments on the assimilation performance with the optimal interpolation method and the ensemble Kalman filter with 61 ensemble members were performed, and the experiments demonstrate that the assimilation performance of the ensemble Kalman filter with 61 ensemble members were improved compared with 30 ensemble members, and with the increase of the ensemble members, the improvement to the initial state of NOx and SO2 with the ensemble Kalman filter will be better than the optimal interpolation method.