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Although the 9-minute mean withdrawal time (m-WT) is often reported to be associated with the optimal adenoma detection rate (ADR), no randomized trials of screening colonoscopy have confirmed the impact of a 9-minute m-WT on adenoma miss rate (AMR) and ADR.A multicenter tandem trial was conducted in 11 centers. Seven hundred thirty-three asymptomatic participants were randomized to receive segmental tandem screening colonoscopy with a 9-minute withdrawal, followed by a 6-minute withdrawal (9-minute-first group, 9MF, n = 366) or vice versa (6-minute-first group, 6MF, n = 367). The primary outcome was the lesion-level AMR.The intention-to-treat analysis revealed that 9MF significantly reduced the lesion-level (14.5% vs 36.6%, P0.001) and participant-level AMR (10.9% vs 25.9%, P0.001), advanced adenoma miss rate (AAMR, 5.3% vs 46.9%, P = 0.002), multiple adenomas miss rate (20.7% vs 56.5%, P = 0.01), and high-risk adenomas miss rate (14.6% vs 39.5%, P = 0.01) of 6MF without compromising detection efficiency ( P = 0.79). In addition, a lower false-negative rate for adenomas ( P = 0.002) and high-risk adenomas ( P0.05), and a lower rate of shortening surveillance schedule ( P0.001) were also found in 9MF, accompanying with an improved ADR in the 9-minute vs 6-minute m-WT (42.3% vs 33.5%, P = 0.02). The independent inverse association between m-WT and AMR remained significant even after adjusting ADR, and meanwhile, 9-minute m-WT was identified as an independent protector for AMR and AAMR.In addition to increasing ADR, 9-minute m-WT also significantly reduces the AMR and AAMR of screening colonoscopy without compromising detection efficiency.

Endometrial dysfunction is closely correlated with the development of multiple severe gynecological disorders including intrauterine adhesion. Accumulating evidence supports that some long non-coding RNAs (lncRNAs) have peptide-coding potential. In this text, the peptide-coding ability of lncRNA SNHG6 was examined. Also, the effects of an SNHG6-encoded peptide on the viability and migration of human endometrial stromal cells (hESCs) and human endometrial epithelial cells (hEECs) and related molecular mechanisms were explored.The peptide-encoding potential of SNHG6 was predicted by FuncPEP and getorf databases and validated by western blot assay. Cell viability was tested by cell counting kit-8 assay. Cell migratory ability was examined by wound healing and transwell migration assays. Protein levels of genes were measured by western blot assay.Prediction analysis suggested that SNHG6 had the potential peptide-coding ability and multiple open-reading frames (ORFs). Western blot validated that SNHG6 ORF#1 and ORF#2 could translate into short peptides. SNHG6 ORF#2 overexpression facilitated cell migration and epithelial-mesenchymal transition (EMT) in hESCs and hEECs, while these effects were abrogated by transforming growth factor-beta (TGF-β)/SMAD signaling inhibitor GW788388. Moreover, GW788388 inhibited the increase of p-SMAD2 and p-SMAD3 levels induced by SNHG6 ORF#2 in hESCs. SNHG6 ORF#2-encoded peptide did not influence endometrial stromal and epithelial cell viability.LncRNA SNHG6 ORF#1 and ORF#2 could translate into small peptides and SNHG6 ORF#2 overexpression promoted cell migration and EMT by activating the TGF-β/SMAD pathway in hESCs and hEECs, suggesting the potential roles of SNHG6-encoded peptides in the development of endometrial stromal and epithelial cells and related gynecological diseases.

In this paper, covalent organic frameworks (COFs) are prepared by solvothermal synthesis using 1,3,5-benzenetricarboxaldehyde and benzidine as ligands. Then, using COFs as a template, AgCOFs with high catalytic activity is prepared by in situ loading silver nanoparticles (AgNC) on the surface of COFs by sodium borohydride reduction method. AgCOFs are characterized by TEM, SEM, FTIR and XRD. At the same time, the catalytic ability of AgCOFs for trisodium citrate-AgNO

To establish and validate a risk prediction model for cervical high-grade squamous intraepithelial lesions (HSIL).This retrospective study included patients who underwent cervical biopsies at the Cervical Disease Centre of Maternal and Child Hospital of Hubei Province between January 2021 and December 2021.A total of 1630 patients were divided into the HSIL + cervical lesion group (n = 186) and the ≤ LSIL cervical lesions group (n = 1444). LSIL, ASC-H, HSIL and SCC, high-risk HPV, HPV16, HPV18/45, multiple HPV strains, acetowhite epithelium, atypical vessels, and mosaicity were independently associated with HSIL + lesions. These factors were used to establish a risk prediction model with a demonstrated area under the curve (AUC) of 0.851 and a C-index of 0.829. Calibration curve analysis showed that the model performed well, with a mean absolute error (MAE) of 0.005. The decision curve showed that the model created by combining the risk factors was more specific and sensitive than each predictive variable.The model for predicting HSIL demonstrated promising predictive capability and might help identify patients requiring biopsy and treatment.

The functions and molecular mechanisms of SPI1-related protein (SPIB) were examined in cervical cancer (CC) cells.Genes related to miscarriage and prognosis in CC were identified by Kaplan-Meier and differential expression analysis, respectively. Cell proliferation, apoptosis, migration, and invasion were examined by cell counting kit-8, flow cytometry, transwell migration, and transwell invasion assays, respectively. The potential functions and molecular mechanisms of SPIB in CC were speculated by gene set enrichment analysis (GSEA) analysis. The mRNA and protein levels of genes were examined by RT-qPCR and western blot assays, respectively. The effect of SPIB on macrophage cells was tested by macrophage recruitment assay and bioinformatics analysis.A total of 753 dysregulated genes were identified in 88 TCGA CC samples with a history of one or more miscarriages versus 208 CC samples with no miscarriage history. Also, 91 genes related to CC prognosis were identified. SPIB, a gene related to both miscarriage and CC prognosis, inhibited Hela cell proliferation, migration, and invasion, and facilitated Hela cell apoptosis. GSEA analysis disclosed that SPIB might play vital roles in immunity, chemokine signaling pathway, and macrophage chemotaxis/activation in CC. Moreover, SPIB inhibited C-X-C motif chemokine ligand 8 (CXCL8), C-C motif chemokine ligand 17 (CCL17), and C-C motif chemokine ligand 25 (CCL25) expression in Hela cells, and SPIB overexpression in Hela cells hampered THP-1 cell migration. Higher SPIB expression was associated with less M2 macrophage infiltration in CC.SPIB inhibited CC-cell progression and hindered macrophage cell migration in CC.

Cervical cancer (CC) is a huge threat to the health of women worldwide. Long non-coding RNA plasmacytoma variant translocation 1 gene (PVT1) was proved to be associated with the development of diverse human cancers, including CC. Nevertheless, the exact mechanism of PVT1 in CC progression remains unclear. Levels of PVT1, microRNA-503 (miR-503), and ADP ribosylation factor-like protein 2 (ARL2) were measured by quantitative reverse transcription-polymerase chain reaction or western blot assay. 3-(4,5)-Dimethylthiazole-2-y1)-2,5-biphenyl tetrazolium bromide (MTT) and flow cytometry were used to examine cell viability and apoptosis, respectively. For migration and invasion detection, transwell assay was performed. The interaction between miR-503 and PVT1 or ARL2 was shown by dual luciferase reporter assay. A nude mouse model was constructed to clarify the role of PVT1 in vivo. PVT1 and ARL2 expressions were increased, whereas miR-503 expression was decreased in CC tissues and cells. PVT1 was a sponge of miR-503, and miR-503 targeted ARL2. PVT1 knockdown suppressed proliferation, migration, and invasion of CC cells, which could be largely reverted by miR-503 inhibitor. In addition, upregulated ARL2 could attenuate si-PVT1-mediated anti-proliferation and anti-metastasis effects on CC cells. Silenced PVT1 also inhibited CC tumor growth in vivo. PVT1 knockdown exerted tumor suppressor role in CC progression via the miR-503/ARL2 axis, at least in part.

Aim:An increasing number of studies have reported a higher frequency of liver injury in COVID-19. Several meta-analyses of the associations between liver injury and COVID-19 had been published, but the dose-response relationship has not been conducted. Therefore, we performed a dose-response meta-analysis to explore this relationship. Methods: PubMed, Web of Science, EMBASE, and four additional Chinese databases were used to collect studies from December 1, 2019 to October 26, 2020. Key information was extracted, and the corresponding model was selected on the basis of the heterogeneity test. The pooled RR, OR, and WMD values were then calculated. Sensitivity analysis and publication bias were also assessed to further demonstrate the stability and reliability of the results. Results: Among the 13298 studies that were initially retrieved, 54 studies met our inclusion criteria and included 9907 participants. There was a dose-response relationship between ALT (OR from 1.0 for ≤40 U/L to 1.556[1.130–2.142] for 40–80 U/L and 1.635[1.176–2.273] for >80 U/L), AST (OR from 1.0 for ≤40 U/L to 1.635[1.180–2.266] for 40–80 U/L and 2.019[1.387–2.938] for >80 U/L) and severe COVID-19. Higher ALT, AST, and TBil were associated with need for ICU admission (WMD 6.45[4.08–8.81], 8.80[6.02–11.57], 2.03[0.91–3.14]), and death due to COVID-19 (WMD 3.22[0.08–6.35], 12.06[6.26–17.85], 2.70[0.72–4.68]). There was no publication bias in this meta-analysis. Conclusion: There were dose-response relationships between ALT, AST, and COVID-19 severity. ALT and AST levels in COVID-19 patients on admission should be considered to be clinical warning indicators, which could provide basis for preventing serious COVID-19 and associated deaths

A novel nanocatalyst of silver-doped carbon nitride quantum dots (AgCNs) was prepared by a microwave procedure, and characterized by electron microscopy, infrared (IR) spectroscopy, surface-enhanced Raman scattering (SERS), resonance Rayleigh scattering (RRS), fluorescence and absorption techniques. Using the slope procedure to evaluate the nanocatalysis, it was found that AgCNs strongly catalyzed the reduction of HAuCl4 with glucose (GL) to generate gold nanoparticles (AuNPs). The produced AuNPs had strong SERS activity and RRS effect. With a Victoria blue B (VBB) molecular probe, the SERS intensity at 1616 cm−1 increased linearly with the concentration of AgCN nanocatalyst. Similar to the SERS, the RRS intensity at 370 nm also increased linearly. Aptamer (Apt) could inhibit the AgCN catalytic activity. K+ combined with Apt to form stable G-quadruplexes and release AgCNs that enhanced the SERS and RRS signals by resuming the catalytic pathway. Coupling the two scattering techniques of inelastic scattering SERS and elastic scattering RRS, we developed a dual-mode scattering method for label-free Apt detection of 5–150 nmol L−1 K+ with a detection limit of 0.92 nmol L−1. Furthermore, we successfully applied a coupled two mode scattering analysis and improved the SERS precision, and proposed a reasonable AgCN catalytic mechanism.

Circular RNAs (circRNAs) have been identified as critical regulators in human cancers, including cervical cancer (CC). However, the precise action of circ_0084904 in cervical carcinogenesis remains to be elucidated. The levels of circ_0084904, microRNA (miR)-802, and Mal, T cell differentiation protein 2 (MAL2) were checked by quantitative real-time PCR (qRT-PCR) or western blot. Ribonuclease R (RNase R) and subcellular localization assays were used to detect the stability and localization of circ_0084904, respectively. Cell colony formation ability was assessed by colony formation assay. Cell cycle and apoptosis were detected by flow cytometry. Cell migration and invasion abilities were gauged by transwell assay. Dual-luciferase reporter and RNA immunoprecipitation (RIP) assays were applied to determine the direct relationship between miR-802 and circ_0084904 or MAL2. The xenograft experiments were performed to evaluate the role of circ_0084904 in tumor growth in vivo. Circ_0084904 was markedly up-regulated in CC tissues and cell lines. Silencing endogenous circ_0084904 impeded cell colony formation, cell cycle progression, migration, invasion, epithelial-mesenchymal transition (EMT), and promoted apoptosis in vitro, as well as diminished tumor growth in vivo. Mechanistically, circ_0084904 targeted miR-802, and the effects of circ_0084904 silencing were mediated by miR-802. MAL2 was directly targeted and inhibited by miR-802, and MAL2 was a functional target of miR-802. Moreover, circ_0084904 modulated MAL2 expression via miR-802. Our study identified circ_0084904 as a novel oncogenic driver in CC depending on the modulation of the miR-802/MAL2 axis, establishing the notion that silencing of circ_0084904 might represent a promising targeted therapy for CC.

Background Our study sought to obtain data which assess the diagnostic value of transvaginal three-dimensional ultrasound (3D-US) combined with color Doppler ultrasound (US) for early cesarean scar pregnancy (CSP). Methods All participants were randomly divided into a Control group diagnosed using 3D-US and a Combination group diagnosed using 3D-US combined with color Doppler US. The preoperative US results were compared with postoperative pathological results. The diagnostic coincidence rate, sensitivity, and specificity of these two examination methods were compared, and their diagnostic results for different types of CSP were analyzed. Finally, the diagnostic effects of both methods were compared and analyzed, and the imaging of CSP was summarized. Results The diagnostic accuracy of transvaginal 3D-US combined with color Doppler US (92.96%) was significantly higher than that of transvaginal 3D-US (71.83%). For different types of CSP, the diagnostic rate of CSP with mixed echogenic mass and partial implantation of gestational sac in the Combination group was markedly higher than that in the Control group. Conclusions Additionally, the sensitivity, specificity, and area under the receiver operating characteristic (ROC) curve (AUC) in the Combination group were higher than those in the Control group. Transvaginal 3D-US combined with color Doppler US can improve the sensitivity, specificity, and accuracy of diagnosis of early CSP, and has important reference value for clinical condition evaluation and treatment options.

Reducing the platinum (Pt) use is of significance to popularize high temperature polymer electrolyte membrane fuel cell (HT-PEMFC) since its average Pt loading in a typical gas diffusion electrode (GDE) normally reaches 0.7 mg cm−2. In this work, an attempt to lower the Pt loading for the electrodes of HT-PEMFC is made by employing low-Pt-content catalysts (20 wt% and 10 wt% Pt/C) with the combination of microporous layer (MPL)-free electrode structure design, by which high Pt utilization and minimum ohmic/mass transfer resistances can be simultaneously maintained. Voltage loss mechanism and the catalyst layer (CL) morphologies of the GDEs are analyzed by polarization curve, electrochemistry impedance spectroscopy, cyclic voltammetry and scanning electron microscopy. The results show that the electrode Pt loading can be lowered to 0.2 mg cm−2 by this strategy but it still demonstrates a maximum Pt-specific performance of 1.6 W mgPt−1 and an area-specific power density of 0.32 W cm−2, which is a considerable improvement on developing HT-PEMFC with low Pt loading. There is a tradeoff between reducing Pt loading and increasing Pt utilization to maintain a superior CL quality, then ensuring that the fuel cell performance is fit for practical applications.

Ex-situ electrochemical characterization techniques could significantly alter or misrepresent the materials of high temperature polymer electrolyte membrane fuel cell (HT-PEMFC) to the point where they are not reflective of their conditions during operation, resulting in difficulties in obtaining realistic fuel cell durability. To minimize this disturbance, we proposed an in-situ low-invasive technique of electrochemical impedance spectroscopy (EIS), combining with polarization curve and Tafel slope analysis, to investigate the performance degradation of HT-PEMFC. The membrane electrode assemblies (MEAs) used in the HT-PEMFC were lab-made but with commercial catalyst and poly(2,5-benzimidazole) (ABPBI) membrane. Two common test modes, i.e. steady-state operation and dynamic-state operation, were employed to mimic practical HT-PEMFC operation. By examining the changes of electrochemical properties of the HT-PEMFC under steady- or dynamic-state operation, the main mechanism for the performance degradation can be determined. The results from the study suggests that a high cell performance decay rate cannot be directly attributed to materials degradation, especially in a short-term steady-state operation. In contrast, the change of Tafel slope can be seen as a clear indicator to determine the extent of catalyst degradation of HT-PEMFC, no matter which test protocol was applied. Post-analysis of TEM on the catalysts before and after tests further confirmed the main mechanism for the performance losses of the HT-PEMFCs underwent two test protocols, while acid loss and membrane degradation were considered to be negligible during the short-term tests.

Carbon monoxide (CO) is a commonly poisonous gas. It is important to detect CO in daily life. Herein, a new and sensitive surface enhanced Raman scattering (SERS) and resonance Rayleigh scattering (RRS) coupled di-mode method was developed for CO, based on gold nano-enzyme catalysis and gold nanoprobes. CO can react with HAuCl4 to generate gold nanoparticles (AuNPs) in pH 5.2 HAc-NaAc buffer. The generated AuNPs exhibited SERS activity at 1620 cm-1 in the presence of Vitoria blue B (VBB) molecular probes, and an RRS peak at 290 nm. Based on the AuNP bifunctional probes, the increased SERS and RRS intensities respond linearly with the concentration of CO in the range of 100&ndash, 1500 ng/mL and 30&ndash, 5230 ng/mL, respectively. To improve the sensitivity, the produced AuNPs were used as nano-enzyme catalysts for the new indicator reaction of HAuCl4-ethanol (En) to amplify the signal. The sensitive SERS method was coupled with the accurate RRS method to develop a sensitive and accurate SERS/RRS di-mode method for determination of 3.0&ndash, 413 ng/mL CO, based on the AuNP-HAuCl4-En nanocatalytic reaction and its product of AuNPs as SERS and RRS bifunctional probes.

The catalytic amplification signal of polystyrene nanosphere (PN) is used to conveniently fabricate the resonance Rayleigh scattering (RRS)/surface-enhanced Raman scattering (SERS) dual-mode method to sensitively and selectively detect urea in food. PN has strong catalysis of the slow nanoreaction of citrate-Ag(I) to produce yellow silver nanoparticles (AgNP), which exhibit strong RRS effect and SERS effect with molecular probes. When aptamer (Apt) is present, the Apt is adsorbed on the PN surface, the catalysis is weakened, the AgNP is reduced, and the SERS/RRS signal is weakened. After adding urea to exhibit specific Aptamer reaction, the Apt is desorbed from the PN surface and the catalysis is restored. As urea increase, the desorbed PNs increase to produce more AgNPs indicator to increase SERS/RRS signal. The increase value △I of SERS/RRS is linearly to urea concentration. Therefore, a sensitive and selective SERS/RRS dual-mode method for urea is established based on aptamers-regulated the catalysis of PNs. This method is applied to the detection of urea in milk with satisfactory results. The relative standard deviation is 3.9–6.8% and the recovery rate is 94.5–102%.

This article has been retracted at the request of the editor due to incorrect format. Therefore, it has been corrected and replaced.

Novel ionic-liquid-functionalized Fe3 O4 magnetic nanoparticles were synthesized by the thiol-ene click reaction. The prepared functionalized Fe3 O4 nanoparticles possessed multiple interactions, such as electrostatic, hydrophobic, and π-π interactions. The functionalized Fe3 O4 nanoparticles were characterized by using Fourier transform infrared spectroscopy, X-ray diffraction, vibrating sample magnetometry, and transmission electron microscopy. Four kinds of linear alkylbenzene sulfonates, namely, sodium decylbenzenesulfonate, sodium undecylbenzene sulfonate, sodium dodecylbenzenesulfonate, and sodium tridecylbenzenesulfonate, were selected as model compounds to evaluate the applicability of adsorbents for extraction and subjected to high-performance liquid chromatography analysis. In addition, the effects of various parameters, such as sorbent amount, pH value, ionic strength, sample volume, extraction time, and elution conditions on extraction efficiency were studied in detail. Under the optimum conditions, good linearities were attained, with correlation coefficients between 0.9912 and 0.9968. The proposed method exhibited limits of detection ranging from 0.061 to 0.099 μg/L for all the target analytes. The spiked recoveries of the target analytes in real water samples ranged from 86.3 to 107.5%, with relative standard deviations lower than 7.96%. The enrichment factors of the analytes ranged from 364 to 391, indicating that the obtained functionalized Fe3 O4 nanoparticles can effectively extract trace target analytes from environmental water samples.

Lysozyme has emerged to be a promising alternative to traditional antibiotics to deal with the increasing antibiotic resistance of bacteria. However, its application is hampered by its inferior bactericidal activity against Gram-negative bacteria. To address this problem, a novel "enzyme-cascade fluorescent high-throughput screening (HTS) method" was designed and constructed based on detection of fluorescence resonance energy transfer (FRET) and enzyme-cascade reaction of lysozyme and protease. As a proof of concept, site-saturation mutagenesis libraries targeting at residues of the unstructured stretch at the N-terminus of

Preparation of multifunctional codoped carbon dots, and their new analytical applications in surface-enhanced Raman scattering (SERS) quantitative analytical method are still challenge. To overcome these problems, the nitrogen/silver-codoped carbon dots (CDN/Ag) with highly catalytic amplification are prepared by microwave method, and characterized by spectrophotometry and electron microscopy. The results show that CDN/Ag can strongly catalyze trisodium citrate-HAuCl4 reaction to generate red nanogold with resonance Rayleigh scattering (RRS) effect and SERS effect using Victoria blue B (VBB) as molecular probes. The CDN/Ag catalytic amplification and specific immunoreaction of clenbuterol (Clen) are coupled with highly sensitive SERS and accurate RRS to fabricate a new dual-spectroscopic strategy with a detection limit of 0.68 pg mL−1 Clen.

A fluorometric clenbuterol immunoassay is described that uses S- and N-co-doped carbon quantum dots as the fluorescent probe. Strongly fluorescent S/N-doped carbon quantum dots (S/N-CDs) were synthesized by hydrothermal method using fructose as the carbon precursor and L-cysteine as S/N sources. The S/N-CDs were characterized by transmission electron microscopy, energy dispersive spectroscopy and Fourier transform infrared spectroscopy (FTIR). Under 350 nm photoexcitation, they display strong purple fluorescence with an emission peak at 405 nm. In pH 4.0 solution, the amino groups (confirmed by FTIR) on the carbon quantum dots were coupled to clenbuterol antibody (Ab) by amine–amine coupling reaction to quench the fluorescence. If clenbuterol (Clen) is added, it binds to the Ab to generate a stable Ab-Clen immunocomplex and free S/N-CD. This causes the fluorescence of nanoprobe to be restored. The fluorescence of the system increases linearly in the 0.07–1.7 ng·mL−1 Clen concentration range. The probe of type S/N4-CD displays the best sensitivity. The detection limit is 23 pg·mL−1.

Highly stable, SERS active and catalytic nanosilver sol (AgNP) was synthesized under the exposure of light wave, using AgNO3 as precursor and sodium citrate as reducer. Under the conditions of pH 7.0 NaH2PO4-Na2HPO4 buffer solution (PBS), the glucose can be catalyzed by glucose oxidase to produce H2O2 specifically. Based on the nanocatalyst and SERS substrate of AgNP, H2O2 can oxidize the 3,3′,5,5′-tetramethylbenzidine (TMB) quickly to form a blue oxidation product (TMBox) that induced the AgNPs aggregation, which exhibited a strong SERS signal at 1606 cm−1. As the concentration of glucose increases, the TMBox molecular probes and AgNPs aggregation increase, and the intensity of SERS peak at 1606 cm−1 increase linearly. Thus, a new SERS strategy for quantitative analysis of 0.33–6.67 μmol/L glucose was developed, with a detection limit of 0.035 μmol/L, coupled the catalysis of nanosilver with glucose oxidase, and label-free molecular probe of TMBox.

To promote the in situ generation of hydrogen peroxide (H2O2) in electro-Fenton system, a new air diffusion electrode (ADE) was put forward in the present work using N-doped multi-walled carbon nanotubes (NCNT) as the catalyst layer, multi-walled carbon nanotubes (CNT) as the diffusion layer, and nickel foam (NF) as the supporting material, respectively. The catalyst layer in ADE was characterized by transmission electron microscopy and X-ray photoelectron spectroscopy. Then the performances of H2O2 accumulation and p-nitrophenol (p-NP) degradation with the electrode (NCNT/NF/CNT ADE) were investigated. The experimental results showed that H2O2 accumulation on the NCNT/NF/CNT ADE was greatly improved by the presence of N doping, and H2O2 accumulation concentration could reach 307 mg L−1 after 120 min at the current intensity of 100 mA. Moreover, the NCNT/NF/CNT ADE presented more effective performance on p-NP degradation than the CNT/NF/CNT ADE or the NF ADE. p-NP of initial 50 mg L−1 could be almost completely removed after 30 min, and the total organic carbon removal efficiency reached 62.61% after 120 min when 0.4 mM Fe2+ was added into the system. The repeatability test suggested that the stability of the NCNT/NF/CNT ADE was very good.

A new Au nanocluster-doped covalent organic framework (AuCOF) was prepared and characterized by electron microscopy and molecular spectroscopy. Based on aptamer-mediated COF nanocatalytic amplification signal strategy, a dual-mode analytical platform of surface-enhanced Raman scattering/resonance Rayleigh scattering (SERS/RRS) was established to detect ultatrace small molecules. The catalysis of AuCOFs on AgNO3-citrate nanoreaction was investigated. The formed yellow silver nanoparticles (AgNPs) exhibit strong RRS and SERS effect. The aptamer (Apt) suppressed the catalysis of AuCOFs to cause the RRS and SERS signals decreasing. Upon addition of target organic molecule such as adenosine triphosphate (ATP), the specific aptamer reaction occurred to restore the catalysis of AuCOFs, which will generate more AgNPs, and resulting in a linear increase in the signals of RRS and SERS. On this basis, inelastic scattering SERS, elastic scattering RRS and SERS/RRS dual-mode biosensors were established for small organic molecules such as ATP, urea, and estradiol, which is of high sensitivity and good accuracy compared to the single mode scattering method.

As an important analysis technology, SERS has the characteristics of fast, sensitive, informative and highly selective. The sensitivity and reproducibility are highly dependent on the properties of SERS substrate, thus it is a study hotspot in SERS quantitative. Although solid phase substrates are widely and early utilized in SERS detection, there are some problems in reproducibility and accuracy and complicated drying process. With development of nanotechnology, facile, highly SERS active, stable and reproducible nanosol substrates were prepared that overcome the problems and fills the gap in this area and expands the application field of SERS quantitative analysis. Using nanoenzyme and bioenzyme catalysis of nanoparticle and molecular reactions to amplify SERS signal, and aptamer to improve the selectivity, some highly sensitive and selective nanosol SERS quantitative analysis methods have been developed with good accuracy. Combining with the work of our group, this paper summarizes the progress of SERS quantitative analysis.

Under ultrasound conditions, a deep yellow fullerene (C60) colloid was prepared, which exhibits two resonance Rayleigh scattering peaks at 385 nm and 530 nm. Urea was reacted with dimethylglyoxime (DMG) to produce 4,5-dimethyl-2-imidazole ketone (DIK), in the presence of stabilizer thiosemicarbazone (TSC). Resonance Rayleigh scattering energy transfer (RRS-ET) was shown to occur between the donor fullerene and acceptor DIK due to an overlap of the DIK absorption and fullerene RRS peaks. Upon an increase in the urea concentration, the RRS-ET was enhanced and the RRS intensity decreased. The decreased RRS intensity was linear to the urea concentration in the range of 6.66–333.00 nmoL L−1, with a detection limit of 2.0 nmoL L−1. Accordingly, a new and simple RRS-ET method was established for detecting trace levels of urea in foods, with satisfactory results.

Epithelial ovarian cancer is one of the primary causes of gynecological cancer mortality. Increasing evidence has suggested that long non-coding RNAs (lncRNAs) may serve a pivotal role in cancer development. To determine whether Lnc SRY-box 4 (SOX4), an lncRNA, promotes the self-renewal of liver tumor cells and contributes to the development of epithelial ovarian cancer, the present study investigated the expression of LncSOX4 in clinical epithelial ovarian cancer tissues and non-cancer controls by reverse transcription-quantitative polymerase chain reaction analysis. In addition, siRNA targeting LncSOX4 was designed and transfected into epithelial ovarian cancer cells to further assess the effect of knocking out LncSOX4 on cellular apoptosis, cell viability, proliferation and the cell cycle. The results demonstrated that the LncSOX4 expression level was significantly upregulated in epithelial ovarian cancer tissues (3.98 vs. 1.71, P

Under the light wave irradiation, the stable and highly surface enhanced Raman scattering (SERS) active silver nanosol (AgNP) was prepared by reduction of AgNO3, using sodium citrate as reducer. Urea reacted with dimethylglyoxime to produce 4,5-dimethyl-2-imidazole ketone that exhibited a strong SERS peak at 1320 cm−1 in the as-prepared AgNPs substrate. Under the selected conditions, the increased SERS intensity ΔI was linear to urea concentration in the range of 8.25–825 nM, with a detection limit of 4.92 nM. Accordingly, a new, simple SERS quantitative analysis method for trace urea in foods was established, with relative standard deviation of 0.92–4.8% and recovery of 97.4–101%.

A heterogeneous electro-Fenton system with fluffy clump steel wire (FCSW) was described for the degradation of p-nitrophenol (p-NP) in water. The influences of the initial pH, initial concentration of FCSW, applied current density on the p-NP, and total organic carbon (TOC) removal percentages were investigated. Compared with the homogeneous electro-Fenton process, the presence of the FCSW catalyst significantly improved the degradation efficiency, the p-NP removal percentages could reach 94.31% after 60 min under the appropriate operating conditions that initial pH value of 3.0, initial FCSW concentration of 3.0 g/L, current density of 3.0 mA/cm2, and the TOC removal percentages could reach 78.96% after 180 min. Aromatic intermediates and carboxylic acids had been identified by chromatographic techniques, and a plausible reaction pathway for p-NP mineralization by heterogeneous electro-Fenton process with FCSW was proposed. The catalytic reusability of FCSW was ultimately evaluated for the repeat...

Summary In this study it was found that ZFP36 is required for ABA-induced antioxidant defence and for the regulation of the cross-talk between NADPH oxidase, H2O2, and MAPK in ABA signalling., C2H2-type zinc finger proteins (ZFPs) have been shown to play important roles in the responses of plants to oxidative and abiotic stresses, and different members of this family might have different roles during stresses. Here a novel abscisic acid (ABA)- and hydrogen peroxide (H2O2)-responsive C2H2-type ZFP gene, ZFP36, is identified in rice. The analyses of ZFP36-overexpressing and silenced transgenic rice plants showed that ZFP36 is involved in ABA-induced up-regulation of the expression and the activities of superoxide dismutase (SOD) and ascorbate peroxidase (APX). Overexpression of ZFP36 in rice plants was found to elevate the activities of antioxidant enzymes and to enhance the tolerance of rice plants to water stress and oxidative stress. In contrast, an RNA interference (RNAi) mutant of ZFP36 had lower activities of antioxidant enzymes and was more sensitive to water stress and oxidative stress. ABA-induced H2O2 production and ABA-activated mitogen-activated protein kinases (MAPKs) were shown to regulate the expression of ZFP36 in ABA signalling. On the other hand, ZFP36 also regulated the expression of NADPH oxidase genes, the production of H2O2, and the expression of OsMPK genes in ABA signalling. These results indicate that ZFP36 is required for ABA-induced antioxidant defence, for the tolerance of rice plants to water stress and oxidative stress, and for the regulation of the cross-talk between NADPH oxidase, H2O2, and MAPK in ABA signalling.

Polyethylene glycol (PEG)-mediated transient gene expression and silencing in protoplasts is widely applied in model plants such as Arabidopsis thaliana and rice. Here, we developed an efficient transient gene expression system based on the PEG-mediated method both in etiolated and green maize mesophyll protoplasts. The results showed that both yellow fluorescent protein encoding gene and glucuronidase encoding gene were efficiently expressed in maize protoplasts. More importantly, double-stranded RNAs (dsRNAs) can also be transfected into maize protoplasts by the PEG-mediated method to specifically silence exogenous and endogenous genes. Our results showed that dsRNA can be used to knockdown both exogenous and endogenous gene expression. Furthermore, bimolecular fluorescence complementation system for the detection of protein–protein interactions in maize protoplasts was developed. We also overexpressed and knockdowned the mitogen-activated protein kinase encoding gene ZmMPK5 to investigate the role of ZmMPK5 in abscisic acid (ABA)-induced antioxidant defense in maize protoplasts. This method here we reported will be valuable for signal transduction study in maize.

In pH 5.5 2-(N-morpholino)-ethanosulfonic acid buffer solution containing 0.25 M NaCl at 80 °C, the single-stranded substrate DNA hybridizes with the enzyme DNA to form double-stranded DNA (dsDNA). The substrate chain of dsDNA could be cracked catalytically by UO2 2+ to produce a short single-stranded DNA (ssDNA) that adsorbed on the nanogold (NG) surface to form a stable nanogold–ssDNA conjugate and then further combine with rhodamine 6G (RhG) to form a NG–ssDNA–RhG conjugate that can be monitored by the surface-enhanced resonance Raman scattering (SERRS) spectral technique at 1,360 cm−1. Under the selected conditions, the increased SERRS intensity ΔI 1360 was linear to UO2 2+ concentration in the range of 5–125 nmol/L, with a detection limit of 1.6 nmol/L. Using a 0.5-μmol/L Hg2+ as enhancer, a 2.5–100-nmol/L UO2 2+ can be determined.

An efficient and enantioselective hydrogenation of 3-substituted unsaturated oxindoles has been developed by an iridium complex of tropos phosphine–oxazoline ligands. It is the first example to prepare chiral C3-mono substituted oxindoles via asymmetric catalysis. And the reaction provides instant access to this kind of compounds with excellent conversion and enantioselectivities (up to 93% ee).

Tropos phosphine-oxazoline ligands have shown interesting coordination behavior and excellent chiral inducing ability in asymmetry catalysis. Here we present a convenient and economic route for the synthesis of this type of ligands. According to this new route, the ligands with different electronic and steric properties have been prepared successfully.

By using the iridium complex of a phosphine-oxazoline ligand with an axis-unfixed biphenyl backbone, a highly enantioselective hydrogenation of the C=C bond of exocyclic α,β-unsaturated carbonyl compounds to afford α-chiral cyclic ketones, lactones and lactams was developed.