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A competitive electrochemical aptamer biosensor for the selective detection of Pb2+ was developed in this study. The PAMAM@Au hybrid materials and the bioprobe MB-GNPs-ssDNA were synthesized with chemical methods. Modified electrode with carboxylated graphene oxide was prepared via electrodeposition. PAMAM@Au was immobilized on the modified electrode using the EDC/NHS crosslinker, and aptamer (Apt) was bound to PAMAM@Au hybrid materials using the glutaraldehyde crosslinker. The assembly of MB-GNPs-ssDNA/Apt/PAMAM@Au/GO/SPCE biosensors was achieved through immobilizing bioprobe onto electrodes, based on the theory of aptamer-complementary chain reactions. The fabricated biosensor was characterized through electrochemical experiments, SEM, AFM, TEM, XPS and FTIR. The biosensor's performance was evaluated in a series of Pb2+ aqueous solutions by differential pulse voltammetry (DPV), and the results demonstrated this biosensor had excellent repeatability, stability, and specificity. The detection range spanned from 0.5 pM/L to 500 nM/L, with a detection limit of 5 fM/L. Consequently, the proposed biosensor can serve as a reliable analytical tool for the sensitive detection of lead ions. • A novel competitive electrochemical aptamer biosensor for detecting lead ions was Designed. • The polyamidoamine (PAMAM) dendrimer encapsulated with nanogold was innovatively synthesized. • A biosignal probe MB-GNPs-ssDNA for enhancing the detection signal of biosensor was synthesized. • The redox property of methylene blue was employed to generate a detectable electrical signal. [ABSTRACT FROM AUTHOR]

Meat adulteration is a growing concern for consumers and researchers, necessitating the development of a simple and robust method for identifying animal sources in meat products. In this study, a double-tailed recombinase polymerase amplification (RPA) integrated with surface-enhanced Raman scattering (SERS) based two-color lateral flow nucleic acid hybridization strip (LFNAHS) was established for simultaneous detection of pork and horse meat. Magenta and cyan gold nanoparticles functionalized with specific probes and Raman dyestuff were used to color the LFNAHS based on RPA amplification products. The assay successfully detected colored test lines for horse and pork adulteration, with quantitative analysis achieved through Raman intensity measurements. The method showed a high specificity with no cross-reactivity and a detection limit of 0.01 % (wt%). Authenticity testing of 40 donkey products yielded results consistent with PCR-agarose gel electrophoresis. This assay can be extended to identify other meat sources by replacing the specific primer sets. This versatile method can be adapted for identifying other meat sources, making it a valuable tool for accurate, sensitive, and quantitative meat authentication in resource-limited settings. [Display omitted] • A new double tailed mRPA with a RPA-SERS-LFNAHS was developed for donkey authentication. • Magenta spherical and cyan urchin AuNPs were synthesized as multicolor labels in the RPA-SERS-LFNAHS. • The specific RPA primers are uniquely designed with tail sequence and a spacer C9. • The detectability of this mRPA-mNAH-LFS assay for horse meat and pork were 0.01 %. • This assay was successfully applied to the authentication of real donkey products. [ABSTRACT FROM AUTHOR]

Invasion of pituitary growth hormone-secreting adenoma into surrounding tissues poses a challenge for complete resection in surgery, which is the main reason for recurrence of this type of cancer. Studies have shown that abnormal methylation of RASSF10 can promote the expression of MDM2 and regulate the tumor microenvironment by affecting the secretion of exosomes. In the present study, we aim to uncover the specific underlying mechanism of this effect. Transwell co-culture assays was performed using GT1.1 cells or exosomes and RAW264.7 cells. RAW264.7 cells were collected for invasion, proliferation and apoptosis assays, RT-qPCR and western blotting. RNA-seq was performed and used to assess the potential molecular pathways of the effect of GT1.1 cell-exosomes on RAW264.7 cells. GT1.1 cells with reduced RASSF10 expression could promote the proliferation and migration of RAW264.7 cells, and promote their expression of osteoclast markers TRAP and CK. The effect of GT1.1 cell exosomes on the RAW264.7-cell phenotype was shown to be achieved through the RASSF10-MDM2 pathway. RNA-seq allowed the identification of PI3K-AKT, MAPK, and calcium signaling as important in this regulation system of RASSF10-MDM2. Our results indicate that GT1.1 cells activate PI3K-AKT, MAPK and calcium signaling via the RASSF10-MDM2 pathway, and promote the differentiation of RAW264.7 cells into osteoclasts through exosomes. This study may provide new ideas to aid in early diagnosis, prognostic assessment and treatment of aggressive pituitary adenomas. • GT1.1 promote the differentiation of RAW264.7 into osteoclasts via exosomes. • RASSF10-MDM2 pathway serves a role in promoting the invasive properties of GT1.1. • GT1.1 activate PI3K-AKT, MAPK and calcium pathway via the RASSF10-MDM2 pathway. • Provide new ideas for studying the mechanism of pituitary adenoma invasion. [ABSTRACT FROM AUTHOR]

We propose a visual strategy for simultaneous detection of chicken and duck ingredients in mutton by integration of a double tailed multiplex recombinase polymerase amplification (mRPA) assay with a multicolor nucleic acid hybridization lateral flow strip (mNAH-LFS) assay. Two colored gold nanoparticles (AuNPs), including gold nanospheres (red) and gold nanoflowers (blue), were synthesized and functionalized with the corresponding nucleic acid probe to target each analyte. The RPA product was analyzed by this two-colored mNAH-LFS assay which includes a red T 1 line for chicken adulteration and a blue T 2 line for duck adulteration. In this RPA reaction, special Spacer9 and tail nucleotide sequence-tagged primers (Tag+Spacer9+F-primer, Tag+Spacer9+R-primer) were used to obtain double-stranded amplicons with specific wobbled sequences that can directly bind with AuNPs-labeled probes (AuNSs-cT 1 hybridized with T 1 , AuNFs-cT 4 hybridized with T 4) and solid-phase probes (biotin-cT 2 hybridized with T 2 , biotin-cT 3 hybridized with T 3) on the mNAH-LFS producing a red or/and cyan color on the T lines. The detection limits of this mRPA-mNAH-LFS assay for chicken and duck were 0.01 % and 0.01 %, respectively. Finally, this mRPA-mNAH-LFS assay was successfully used to authenticate 59 commercial meat products. In conclusion, this mRPA-mNAH-LFS is a sensitive, accurate, and cost-effective approach for meat quality assurance and traceability. • A new double tailed mRPA with a mNAH-LFS was developed for mutton authentication. • Red AuNSs and blue AuNFs were synthesized as multicolor labels in the mNAH-LFS. • The specific RPA primers are uniquely designed with tail sequence and a spacer C9. • The sensitivity of this mRPA-mNAH-LFS assay for chicken and duck were 0.01 %. • This assay was successfully applied to the authentication of real mutton products. [ABSTRACT FROM AUTHOR]

The host-virus interaction during the cellular entry of Japanese encephalitis virus (JEV) is poorly characterized. The ubiquitin-proteasome system (UPS), the major intracellular proteolytic pathway, mediates diverse cellular processes, including endocytosis and signal transduction, which may be involved in the entry of virus. Here, we showed that the proteasome inhibitors, MG132 and lactacystin, impaired the productive entry of JEV by effectively interfering with viral intracellular trafficking at the stage between crossing cell membrane and the initial translation of the viral genome after uncoating. Using confocal microscopy, it was demonstrated that a proportion of the internalized virions were misdirected to lysosomes following treatment with MG132, resulting in non-productive entry. In addition, using specific siRNAs targeting ubiquitin, we verified that protein ubiquitination was involved in the entry of JEV. Overall, our study demonstrated the UPS is essential for the productive entry of JEV and might represent a potential antiviral target for JEV infection. [ABSTRACT FROM AUTHOR]

Meat adulteration is becoming increasingly prominent in the global market. Therefore, a robust, sensitive, and affordable rapid detection strategy for identifying meat species is urgently needed. In this study, we developed a novel strategy using chicken-specific recombinase polymerase amplification (RPA) coupled with nucleic acid hybridization lateral flow strip (NAH-LFS) for the rapid detection of chicken adulteration. In an isothermal RPA reaction, chicken mitochondrial DNA (as target) was amplified at 39 °C for 15 min. Both the forward and reverse primers contained three parts, namely the specific binding region, a special abasic spacer 9 (iSp9), and the tag sequence (forward primer tag, F-tag, and reverse primer tag, R-tag). The specific binding region and tag sequences were linked by iSp9, which could also inhibit extension by DNA polymerase, producing a double-stranded amplicon with two tag sequences (F-tag and R-tag) at the two opposite ends. The F-tag and R-tag can complementarily hybridize with probes on AuNPs and the test line, respectively, showing red color on the test line. This visual detection strategy does not require expensive equipment, and the entire detection procedure can be performed within 20 min. Specificity tests with 10 other animal samples showed no cross-reactivity. The RPA-NAH-LFS strategy could detect 0.01% (w/w) chicken in the chicken/beef meat mixture. To verify its utility, this assay was used to authenticate 30 commercial beef samples; the results were 100% consistent with those obtained using the PCR- agarose gel electrophoresis (AGE). In conclusion, the RPA-NAH-LFS assay serves as an accurate, sensitive, and cost-effective method to evaluate chicken adulteration and traceability in meat. • A visual method based on RPA-NAH-LFS was developed to detect chicken adulteration. • Unique chicken-specific primers were designed with spacer9 and tail sequence. • This visual detection strategy did not require expensive experimental equipment. • The RPA-NAH-LFS could be observed by non-expert operators within 20 min at 39 °C. • The detection limit of this RPA-NAH-LFS assay for chicken adulteration was 0.01%. [ABSTRACT FROM AUTHOR]

Identifying unknown drug interactions is of great benefit in the early detection of adverse drug reactions. Despite existence of several resources for drug–drug interaction (DDI) information, the wealth of such information is buried in a body of unstructured medical text which is growing exponentially. This calls for developing text mining techniques for identifying DDIs. The state-of-the-art DDI extraction methods use Support Vector Machines (SVMs) with non-linear composite kernels to explore diverse contexts in literature. While computationally less expensive, linear kernel-based systems have not achieved a comparable performance in DDI extraction tasks. In this work, we propose an efficient and scalable system using a linear kernel to identify DDI information. The proposed approach consists of two steps: identifying DDIs and assigning one of four different DDI types to the predicted drug pairs. We demonstrate that when equipped with a rich set of lexical and syntactic features, a linear SVM classifier is able to achieve a competitive performance in detecting DDIs. In addition, the one-against-one strategy proves vital for addressing an imbalance issue in DDI type classification. Applied to the DDIExtraction 2013 corpus, our system achieves an F 1 score of 0.670, as compared to 0.651 and 0.609 reported by the top two participating teams in the DDIExtraction 2013 challenge, both based on non-linear kernel methods. [ABSTRACT FROM AUTHOR]

Abstract: We report a RNA species of 429 nucleotides derived from the 3′ untranslated region of the viral genome in Dengue 2 virus (DENV-2) infected cells. The 3′ terminal of viral RNA contained specific conserved structures that are important for the production of subgenomic RNA. Transient replicon assays suggested that loss of this small RNA has little effect on viral replication, and genetic analysis using recombinant viruses demonstrated that the existence of this subgenomic RNA is not essential for the life cycle of the DENV-2. Results from cytotoxicity and apoptosis assay revealed that the generation of subgenomic RNA is significant for DENV-2 viral cytopathicity and virus-induced apoptosis; and the deficiency could be partially restored by providing subgenomic RNA in trans from transfection. In addition, we found that subgenomic RNA modulates the phosphatidylinositol 3-kinase (PI3k)/Akt signaling pathway through a Bcl-2-related mechanism, resulting in apoptotic cell death. [Copyright &y& Elsevier]

The adsorption of Cd(II), Zn(II) and Ni(II) from aqueous solutions in binary and ternary component systems by tourmaline was investigated. Kinetic data were accurately fitted to pseudo-second order and internal diffusion models, which indicated that the adsorption of heavy metals occurred on the interior surface of the sorbent and internal diffusion was the controlling mechanism during heavy metal ion adsorption but was not the only rate-controlling step. Additionally, tourmaline had a very good adsorption capacity for Cd(II), Zn(II) and Ni(II) in multi-component aqueous solutions at strongly acidic pH values (in contrast to industrial wastewater pH values). This good adsorption capacity is attributed to the fact that tourmaline can automatically adjust the pH values of acidic (except pH 2.0 and 3.0), neutral or alkaline aqueous solutions to 6.0. Adsorption isotherms and separation factors showed that tourmaline displays a high selectivity toward one metal in a two-component or a three-component system with an affinity order of Cd(II) > Zn(II) > Ni(II). Thermodynamic parameters indicated that heavy metal adsorption was feasible, spontaneous, and endothermic. Therefore, tourmaline should be explored as a material for removing pollutants from the strongly acidic wastewater. [Copyright &y& Elsevier]

• 1592 N6-methyladenosine modification regulators were identified from 65 representative species. • A comparative analysis was performed on N6-methyladenosine modification regulators in a larger scale. • Distinct phylogenetic relationships for N6-methyladenosine modification regulators were reported. As a reversible modification, N 6-methyladenosine (m6A) plays key roles in series of biological processes. Although it has been found that m6A modification is regulated by writers, erasers and readers, their evolutionary processes are still not clearly and systematically described. In the present work, we identified 1592 m6A modification regulators from 65 representative plant species and performed the phylogenetic relationships, sequence structure, selection pressure, and codon usage analysis across species. The regulators from different species or subfamilies were distinguishable based on the phylogenetic trees. Although the gene structure was structurally and functionally conserved for each kind of regulators, the unique exon/intron structures and motif organizations were observed among different families. The selection pressure analysis demonstrated that the regulators experienced purifying selection. Interestingly, the selection pressure for the regulators in higher plants was more relaxed, indicating that they might have acquired new functions during evolution. In addition, the different codon usage preferences were observed for the different kinds of m6A modification regulators. These results will not only facilitate our understanding of the evolution of m6A regulators, but also shed light on how the evolutionary differences affect their functional divergence. [ABSTRACT FROM AUTHOR]