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A portable dual-mode PDMS-based microfluidic chip aptasensor was developed to detect bovine pregnancy-associated glycoproteins (bPAG) in bovine milk. Reagents within the chip chambers underwent reactions driven by gravity, where pre-encoded rich C sequences on the complementary strand of the aptamer facilitated the generation of abundant G-quadruplexes via subsequent RPA reaction, which activated the chromogenic substrates and fluorogenic precursors in the chip, producing distinct colorimetric and fluorescent signals. These signals were captured by our developed smartphone application and converted into RGB values, further enabling the quantification of bPAG with detection limits of 0.079 ng/mL and 0.024 ng/mL for colorimetric and fluorescent modes, respectively, over a linear range of 0.1-100 ng/mL. Bovine milk and other animal source milk were evaluated in the proposed assay, accurate identification results were obtained, indicating significant potential in bovine milk monitoring. The work further provided a valuable reference for point-of-care testing of non-nucleic acid targets in food samples., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Timely and accurate detection of trace mycotoxins in agricultural products and food is significant for ensuring food safety and public health. Herein, a deep learning-assisted and entropy-driven catalysis (EDC)-Argonaute powered fluorescence single-particle aptasensing platform was developed for ultrasensitive detection of fumonisin B 1 (FB 1 ) using single-stranded DNA modified with biotin and red fluorescence-encoded microspheres as a signal probe and streptavidin-conjugated magnetic beads as separation carriers. The binding of aptamer with FB 1 releases the trigger sequence to mediate EDC cycle to produce numerous 5'-phosphorylated output sequences, which can be used as the guide DNA to activate downstream Thermus thermophilus Argonaute ( Tt Ago) for cleaving the signal probe, resulting in increased number of fluorescence microspheres remaining in the final reaction supernatant after magnetic separation. Subsequently, through fast and accurate counting of red bright particles in the captured confocal fluorescence images from the supernatant via a YOLOv9 deep learning model, the sensitive and specific detection of FB 1 could be realized. This approach has a limit of detection (LOD) of 0.89 pg/mL with a linear range from 1 pg/mL to 100 ng/mL, and satisfactory recovery (87.2-113.5%) in real food samples indicates its practicality. The integration of the aptamer and EDC with Tt Ago broadens the target range of Argonaute and enhances sensitivity. Furthermore, incorporating deep learning significantly improves the analytical efficiency of single-particle detection. This work provides a promising analytical strategy in biosensing and promotes the application of fluorescence single-particle detection in food safety monitoring.

Cuproptosis is crucial in the development of various liver diseases, yet its involvement in alcoholic liver disease (ALD) remains poorly understood. In this study, we screened cuproptosis-related genes (CRGs) regulating ALD and explored their potential molecular mechanisms. Bioinformatic methods were employed to screen CRGs in ALD, analyze their functional enrichment, signaling pathways, transcriptional regulation, relationship with the immune microenvironment and pathogenic genes, and corresponding single nucleotide polymorphism pathogenic regions, and construct transcription factor-miRNA-mRNA networks. Liver tissues from patients with ALD and NIAAA model mice were collected and assessed for copper deposition. CRG expression in the livers of patients was analyzed using RNA sequencing. CRG expression in liver tissues was also analyzed using RNA sequencing and verified using quantitative polymerase chain reaction (RT-qPCR), western blotting, and immunofluorescence. Dihydrolipoamide S-acetyltransferase (DLAT), glutaminase (GLS), and cyclin-dependent protein kinase inhibitor 2A (CDKN2A) were identified as potential ALD-associated CRGs with significant diagnostic value. Consistent with the results of bioinformatics analysis, these genes were notably upregulated in liver tissues from both patients with ALD and NIAAA model mice. All three ALD-associated CRGs were regulated by E2F transcription factor 1 (E2F1) and showed a significant negative correlation with the expression of ADH1B and ALDH2, key enzymes in alcohol metabolism. They were positively correlated with PI3K/AKT/mTOR, IFN-γ response, and complement signaling pathways but negatively correlated with bile acid and xenobiotic metabolism. This study identified DLAT, GLS, and CDKN2A as the ALD-associated CRGs, providing valuable insights into their molecular mechanisms in ALD pathogenesis, which may inform diagnosis and treatment., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Nowadays the enzymatic approaches are the most promising strategies for mycotoxins detoxification in food stuffs. Herein, the dye-decolorizing peroxidase RhDypB from Rhodococcus jostii was studied for its ability to degrade two mycotoxins in both free and the immobilized enzyme forms. This enzyme was recombinantly expressed and purified, while Fe 3 O 4 nanoparticles were prepared and modified with chitosan as the immobilization carrier. The immobilized enzyme Fe 3 O 4 @CS@RhDypB demonstrated degradation rate of 85.61 % toward aflatoxin B 1 , while it was firstly found to be able to degrade zearalenone with the rate of 86.52 %, at pH 4.0 on 30 °C. The degradation products were identified as aflatoxin Q 1 and 15-OH-ZEN respectively. After 5 cycles of reuse, Fe 3 O 4 @CS@RhDypB still exhibited degradation rates of 38.50 % and 49.76 % toward the mycotoxins, indicating its high reusability. Moreover, Fe 3 O 4 @CS@RhDypB exhibited excellent stability after 10 days of storage. This work identified potential applications of nanoparticle-immobilized enzyme for biodegradation of mycotoxins in food industry., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

β-Conglycinin is the main allergen present in soybeans, and it is causing wide concern due to its notable allergenicity, heat, and digestive enzyme resistance. Screening for aptamers that both recognize β-conglycinin and inhibit the allergic reactions that it triggers is necessary. Conventional aptamer screening is labor-intensive, requires skilled personnel, and has limited reproducibility. To address these limitations, an automated device was developed to enhance the efficiency of aptamer selection in Capture-SELEX. The device achieves highly integrated, reproducible, and accurate contamination control. Using this device, a high-affinity and specific aptamer, β-5, was selected with a K d = 18.24 ± 2.42 nM for β-conglycinin, as confirmed by isothermal titration calorimetry and fluorescence polarization. Thermodynamic analysis revealed that enthalpy-driven binding and docking simulations clarified the recognition mechanism. Overall, this automated device enables high-efficiency aptamer generation for certain targets, with aptamer β-5 expected to play a vital role in the detection of β-conglycinin and the targeted inhibition of its allergic reaction.

Aptamers are excellent recognition molecules obtained from systematic evolution of ligands by exponential enrichment (SELEX) that have been extensively researched for constructing aptasensors. However, in the process from SELEX to the construction of aptasensors, there are many disadvantages, such as tedious and repetitive operations, interference from external factors, and low efficiency, which seriously limits their application scope and development. Introducing the microfluidic technology can realize the integration and intelligence of SELEX and aptasensing, improve the efficiency of SELEX, and enhance the detection performance and convenience of aptasensing. Hence, in this review, the characteristics of various chips based on different driving forces are described firstly. And then summarizing the design of microfluidic devices based on different SELEX methods and showing the strategies of microfluidic aptasensors based on different detection modes. Finally, discussing the difficulties and challenges encountered when microfluidic is integrated with the SELEX and the aptasensors., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Aptamers, as a kind of recognition molecules with stable nature and excellent binding ability, are usually obtained by systematic evolution of ligands by exponential enrichment (SELEX). However, the traditional SELEX suffers from the problems of low screening efficiency as well as excessive number of screening rounds, making the screening a cumbersome process, which greatly restricts the application and development of aptamers. Here, a microfluidic SELEX platform based on capture SELEX was designed and developed to make the screening more integrated and convenient. Nε-carboxymethyl lysine (CML) and Nε-carboxyethyl lysine (CEL), were selected as targets for screening, and candidate aptamers were identified after eight rounds of screening using the microfluidic SELEX platform. Following isothermal titration calorimetry (ITC) and SYBR GREEN I (SGI) analysis, aptamer S2 was identified with the highest affinity and specificity. Aptamer S2 was further optimized based on the binding sites explored by molecular docking. Eventually, the truncated aptamer S2-40 was obtained, which was superior to S2 in terms of affinity and specificity with dissociation constant (Kd) of 6.65 ± 3.07 μM (ITC) and 42.1 ± 9.34 nM (SGI), respectively. This indicated that the microfluidic SELEX platform offers a more integrated and convenient approach to aptamer screening., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Acrylamide (AA) in heat-processed foods has emerged as a global health problem, mainly carcinogenic, neurotoxic, and reproductive toxicity, and an increasing number of researchers have delved into elucidating its toxicological mechanisms. Studies have demonstrated that exposure of HepG2 by AA in a range of concentrations can induce the upregulation of miR-21 and miR-221. Monitoring the response of intracellular miRNAs can play an important role in unraveling the mechanisms of AA toxicity. Here, multicolor aggregation induced emission nano particle (AIENP) probes were constructed from three AIE dyes for simultaneous imaging of intracellular AA and AA-induced miR-21/miR-221 by combining the recognition function of AA aptamers and the signal amplification of a DNAzyme walker. The surface of these nanoparticles contains carboxyl groups, facilitating their linkage to a substrate chain modified with a fluorescent quencher group via an amide reaction. Optimization experiments were conducted to determine the optimal substrate-to-DNAzyme ratio, confirming its efficacy as a walker for signal amplification. Sensitive detection of AA, miR-21 and miR-221 was achieved in extracellular medium, with detection limits of 0.112 nM for AA, 0.007 pM and 0.003 pM for miR-21 and miR-221, respectively, demonstrating excellent selectivity. Intracellularly, ZIF-8 structure collapsed, releasing Zn 2+ , activating DNAzyme cleavage activity, and the fluorescence of multicolor AIENPs within HepG2 cells gradually recovered with increasing stimulation time (0-12 h) and concentrations of AA (0-500 μM). This dynamic response unveiled the relationship between AA exposure and miR-21/miR-221 expression, further validating the carcinogenicity of AA., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Objective: Weight bias internalization (WBI) is a robust, positive correlate of negative health outcomes; however, this evidence base primarily reflects cisgender individuals from Western cultural contexts. Gender-diverse individuals from non-Western cultural contexts (e.g., China) are at potentially high risk for WBI. Yet, no research has examined WBI and associated negative health consequences in this historically underrepresented population., Method: A cross-sectional, online survey sampled Chinese gender-diverse individuals (N = 410, M age  = 22.33 years). Variables were self-reported, including demographics, WBI, body shame, body dissatisfaction, disordered eating, physical and mental health status, and gender minority stress (e.g., internalized cisgenderism). Analyses included correlations and multiple hierarchical regressions., Results: Pearson bivariate correlations demonstrated associations between higher WBI and more eating and body image disturbances and poor physical and mental health. After adjusting for age, BMI, gender identity, and gender minority stress, higher WBI was uniquely and positively associated with higher body shame, higher body dissatisfaction, higher disordered eating, and poor physical and mental health. Notably, WBI accounted for more unique variance in eating and body image disturbances (13%-25% explained by WBI) than physical and mental health (1%-4% explained by WBI)., Discussion: While replication with longitudinal and experimental designs is needed to speak to the temporal dynamics and causality, our findings identify WBI as a unique, meaningful correlate of eating and body image disturbances in Chinese gender-diverse adults., (© 2024 Wiley Periodicals LLC.)

Research on self-assembled deoxyribonucleic acid (DNA) nanostructures with different shapes, sizes, and functions has recently made rapid progress owing to its biocompatibility, programmability, and stability. Among these, triangular unit-based DNA nanostructures, which are typically multi-arm DNA tiles, have been widely applied because of their unique structural rigidity, spatial flexibility, and cell permeability. Triangular unit-based DNA nanostructures are folded from multiple single-stranded DNA using the principle of complementary base pairing. Its shape and size can be determined using pre-set scaffold strands, segmented base complementary regions, and sequence lengths. The resulting DNA nanostructures retain the desired sequence length to serve as binding sites for other molecules and obtain satisfactory results in molecular recognition, spatial orientation, and target acquisition. Therefore, extensive research on triangular unit-based DNA nanostructures has shown that they can be used as powerful tools in the biosensing field to improve specificity, sensitivity, and accuracy. Over the past few decades, various design strategies and assembly techniques have been established to improve the stability, complexity, functionality, and practical applications of triangular unit-based DNA nanostructures in biosensing. In this review, we introduce the structural design strategies and principles of typical triangular unit-based DNA nanostructures, including triangular, tetrahedral, star, and net-shaped DNA. We then summarize the functional properties of triangular unit-based DNA nanostructures and their applications in biosensing. Finally, we critically discuss the existing challenges and future trends., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

Mental health disparities in transgender and gender diverse (TGD) populations call for more research examining gender minority stressors (GMS) as antecedents to their psychological distress, especially for the long-underrepresented groups living in conservative societies towards gender minorities. Furthermore, some questions remain underexamined, including the relative, independent influences of various GMS on TGD people's mental well-being (i.e., uniqueness of each stressor); how these stressors would configurate with each other in distinctive patterns to characterize subgroups of TGD people (i.e., beyond-average heterogeneity); and how these stressors would constitute a psychological network and vary in their centrality in that network (i.e., holistic complexity). To narrow such gaps, we examined the links between GMS and TGD people's psychological distress, using survey data collected in 2023 from 410 Chinese TGD people (Mean age  = 22.33 years, SD = 4.27; 306 transgender, 70 non-binary/gender-queer/gender-fluid, 26 agender/gender-neutral, 3 intersex, and 5 others). We approached such links from three perspectives. First, variable-centered analyses indicated that while different GMS were considered simultaneously, internalized transphobia, preoccupation with gender dysphoria, and gender-related victimization were uniquely associated with psychological distress. Second, person-centered analyses yielded a 3-profile solution. Psychological distress varied systematically across profiles. Last, network analyses revealed a 3-cluster structure: Distal, Proximal Internal, and TGD-Specific Stressors. Preoccupation with gender dysphoria was the most central node. These findings contribute to a more nuanced understanding of the implications of GMS for TGD people's mental well-being. GMS related to internal struggles with gender identity might be among the central intervention targets to prevent/reduce TGD people's psychological distress., Competing Interests: Declarations. Conflicts of interest: The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Ethics Approval: This study was performed in line with the principles of the Declaration of Helsinki, in accord with APA ethical standards and within the terms of the institutional review board at the study’s home institution (Project Title: Body Image and Eating Disorders of Transgenders in Chinese Context; IRB approval institution: The Chinese University of Hong Kong, Shenzhen, Protocol No. EF20230329001). Informed Consent: Freely-given, informed consent to participate in the study had been appropriately obtained from all participants. Transparency and Openness: This study’s design and its analysis plan were not pre-registered. All data, materials, and analysis code for this study are available upon reasonable request by emailing the corresponding author. The data and narrative interpretation presented in this article have not been previously disseminated or shared in any form on any platforms., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

A truncated aptamer (designated A24-3) was identified that specifically binds to bovine pregnancy-associated glycoproteins (bPAG9) with a low dissociation constant (2.04 nM) through two truncation approaches. Circular dichroism spectroscopy indicated that A24-3 formed parallel G-quadruplexes, which was subsequently confirmed using nuclear magnetic resonance (NMR) spectroscopy. Furthermore, a molecular dynamics simulation was employed to investigate the recognition mechanism of A24-3 and bPAG9. Interaction analysis showed that A24-3 folded into a parallel G-quadruplex structure with three G-tetrads, primarily through numerous hydrogen bonds and hydrophobic and π-π interactions. Finally, a novel colorimetric aptasensor was developed for detecting bPAG9 using A24-3 and an Fe-based metal-organic framework as target recognition elements and enzyme mimics, respectively. The method demonstrated a broad detection range from 0.5 to 50 ng/mL, with a low detection limit of 0.03 ng mL -1 , and exhibited a good recovery (91.0-102%) for bPAG9-spiked serum samples. Additionally, the aptasensor was successfully applied to detecting the pregnancy-specific biomarker bPAGs in serum samples., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

Bacterial infections have been seriously endangering public health and life, making it imperative to explore novel anti-infection strategies for their control. Herein, we constructed a DNA hydrogel encoded with aptamers (Apt-hydrogel) to inhibit Shiga toxin II (Stx2) toxicity, thereby alleviating Escherichia coli (EHEC) infection. The Apt-hydrogel was formed by two Y-shaped DNA scaffolds through rational design, where one end of Y was encoded with an aptamer sequence targeting the B subunit of Shiga toxin II (Stx2B). The Apt-hydrogel not only retained the high affinity of the aptamer but also provided protection for the aptamer, endowing it with better stability and biocompatibility. The results from in vitro and in vivo demonstrated good mediation effects of the Apt-hydrogel on Stx2 toxicity and confirmed its excellent inhibition activity. We hypothesized that the mechanism could be attributed to the high affinity of Apt-hydrogel for Stx2B, which effectively occupies the active site of Stx2B and its receptor Gb3. This interaction enhanced steric hindrance, thereby mediating their interaction and preventing Stx2 from entering the cell to exert toxicity. We anticipate that the novel Apt-hydrogel will expand the usage of aptamers and provide a new dimension for the Apt-hydrogel as a promising blocking assistant to inhibit Shiga toxin infections via a strong steric hindrance effect.

Background: Solid tumors are characterized by a low blood supply, complex stromal architecture, and immunosuppressive milieu, which inhibit CAR-T cell entry and survival. CXCR5 has previously been employed to increase CAR-T cell infiltration into CXCL13+ cancers. On the other hand, IL-7 improves the survival and persistence of T cells inside a solid tumor milieu., Methods: We constructed a novel NKG2D-based CAR (C5/IL7-CAR) that co-expressed CXCR5 and IL-7. The human osteosarcoma cell lines U-2 OS, 143B, and Mg63 highly expressed MICA/B and CXCL13, thus presenting a perfect avenue for the present study., Results: Novel CAR-T cells are superior in their activation, degranulation, and cytokine release competence, hence lysing more target cells than conventional CAR. Furthermore, CXCR5 and IL-7 co-expression decreased the expression of PD-1, TIM-3, and TIGIT and increased Bcl-2 expression. Novel CAR-T cells show enhanced proliferation and differentiation towards the stem cell memory T cell phenotype. C5/IL7-CAR-T cells outperformed conventional CAR-T in eradicating osteosarcoma in mouse models and displayed better survival. Additionally, CXCR5 and IL-7 co-expression enhanced CAR-T cell numbers, cytokine release, and survival in implanted tumor tissues compared to conventional CAR-T cells. Mechanistically, C5/IL7-CAR-T cells displayed enhanced STAT5 signaling., Conclusion: These findings highlight the potential of CXCR5 and IL-7 co-expression to improve CAR-T cell therapy efficacy against osteosarcoma., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Hui, Farooq, Chen, Ajmal, Ren, Xue, Ji, Du, Wu and Jiang.)

Aptamers, as short single-stranded nucleic acids, can bind to targets in a similar way to antibodies. Relying on the advantages of low cost, high stability, and flexibility, they are widely applied in biosensors, disease therapy, and synthetic biology. As an aptamer screening method, the Systematic Evolution of Ligands by Exponential Enrichment (SELEX) offers almost unlimited possibilities for functional aptamer generation. However, at present, the SELEX procedure has not reached a satisfactory level, and it still faces some challenges in practical application, such as the relatively blind initial library, laborious and time-consuming selection process, typically requires 9-20 rounds for screening, and the entire process generally extends over 2-3 months, and sub-optimal performance of aptamers obtained. In the past few years, researchers have made great efforts to address these obstacles. Hence, in this review, we first summarize the aptamer screening mechanism and the existing limitations of SELEX. Then analyze the principle and technical key points of the SELEX optimization screening strategy. By incorporating rational library design, novel screening awareness, and advanced screening equipment, the number of aptamer screening cycles is significantly reduced to <8 rounds, with some methods achieving single-round screenings. This has led to a considerable decrease in the overall screening time to <3 weeks, while simultaneously enhancing the performance of the aptamers. Finally, critically discuss the present challenges and future directions of aptamer screening. This review aims to provide a practical reference for designing suitable aptamer screening methods.

Thermostable direct hemolysin (TDH) is a key virulence factor of Vibrio parahaemolyticus, capable of causing seafood-mediated outbreaks of gastroenteritis, posing a threat to the aquatic environment and global public health. In the present study, we explored a multivalent aptamer-mediated inhibition strategy to mitigate TDH toxicity. Based on the characteristic structure of TDH, a stable multivalent aptamer, Ap3-5, was rationally designed by truncation, key fragment evolution, and end fixation. Ap3-5 exhibited strong affinity (K d =39.24 nM), and thermal (T m =57.6 °C) and enzymatic stability. In silico studies also revealed that Ap3-5 occupied more active sites of TDH and covered its central pore, indicating its potential as a blocking agent for inhibiting TDH toxicity. In the hemolysis assay, Ap3-5 significantly suppressed the hemolytic effect of TDH. A cellular study revealed a substantial (∼80 %) reduction in TDH cytotoxicity. Supporting these findings, in vivo trials confirmed the inhibitory action of Ap3-5 on both the acute and intestinal toxicity of TDH. Overall, benefiting from the strong binding affinity, high stability, and multisite occupation of the multivalent aptamer with TDH, Ap3-5 displayed robust potential against TDH toxicity by inhibiting membrane pore formation, providing a new approach for alleviating bacterial infections., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Shiga toxin (Stx) is the definitive virulence factor of Stx-producing Escherichia coli. This bacterial pathogen can contaminate food and threaten human health. Binding of the B subunit of Stx to the specific receptor globotriaosylceramide (Gb3) on the cell membrane is a key step for Stx to enter cells and exert its toxicity. In this work, we aimed to screen for aptamers targeting the Stx 2 B subunit, to interfere with the interaction of Stx2 B subunit and Gb3, thereby blocking Stx2 from entering cells. The results of molecular simulation docking, competitive ELISA, flow cytometry, and laser confocal microscopy confirmed that aptamers S4, S5, and S6 can mediate the interaction between Stx2 B subunit and Gb3. To further improve the inhibition effect, multiple aptamer sequences were tailored and were fused. The bivalent modification aptamer B2 inhibited Stx2 toxicity to Vero cells with inhibition rate of 53 %. Furthermore, the aptamer B2 reduced Stx2 damage to the mice, indicating that it has great potential to interfere with Stx2 binding to Gb3 receptors in vivo and in vitro. This work provides a theoretical and experimental basis for the application of aptamers in the inhibition of Stx2 toxicity and control of food hazards., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Malachite green (MG) has been illicitly employed in aquaculture as a parasiticide, however, its teratogenic and carcinogenic effects pose a significant human health threat. Herein, a dual-mode colorimetric and electrochemical aptasensor was fabricated for MG detection, capitalizing on the robust catalytic and peroxidase-like activity of P-CeO 2 NR@Mxene and good capture efficiency of a tetrahedral DNA nanostructure (TDN) designed with multiple aptamers (m-TDN). P-CeO 2 NR@Mxene-modified complementary DNA (cDNA) served as both colorimetric and electrochemical probe. m-TDN was attached to AuE to capture MG and P-CeO 2 NR@Mxene/cDNA. The superior aptamer and MG binding to cDNA regulated signals and enabled precise MG quantification. The further introduced Exo I enabled aptamer hydrolysis, releasing MG for further binding rounds, allowing target recycling amplification. Under the optimal conditions, the aptasensor reached an impressively low detection limit 95.4 pM in colorimetric mode and 83.6 fM in electrochemical mode. We believe this dual-mode approach holds promise for veterinary drug residue detection., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Food safety is a global issue in public hygiene. The accurate, sensitive, and on-site detection of various food contaminants performs significant implications. However, traditional methods suffer from the time-consuming and professional operation, restricting their on-site application. Hydrogels with the merits of highly porous structure, high biocompatibility, good shape-adaptability, and stimuli-responsiveness offer a promising biomaterial to design sensors for ensuring food safety. This review describes the emerging applications of hydrogel-based sensors in food safety inspection in recent years. In particular, this study elaborates on their fabrication strategies and unique sensing mechanisms depending on whether the hydrogel is stimuli-responsive or not. Stimuli-responsive hydrogels can be integrated with various functional ligands for sensitive and convenient detection via signal amplification and transduction; while non-stimuli-responsive hydrogels are mainly used as solid-state encapsulating carriers for signal probe, nanomaterial, or cell and as conductive media. In addition, their existing challenges, future perspectives, and application prospects are discussed. These practices greatly enrich the application scenarios and improve the detection performance of hydrogel-based sensors in food safety detection.

Listeria monocytogenes (LM) is one of the most invasive foodborne pathogens that cause listeriosis, making it imperative to explore novel inhibiting strategies for alleviating its infection. The adhesion and invasion of LM within host cells are partly orchestrated by an invasin protein internalin A (InlA), which facilitates bacterial passage by interacting with the host cell E-cadherin (E-Cad). Hence, in this work, we proposed an aptamer blocking strategy by binding to the region on InlA that directly mediated E-Cad receptor engagement, thereby alleviating LM infection. An aptamer GA8 with a robust G-quadruplex (G4) structural feature was designed through truncation and base mutation from the original aptamer A8. The molecular docking and dynamics analysis showed that the InlA/aptamer GA8 binding interface was highly overlapping with the natural InlA/E-Cad binding interface, which confirmed that GA8 can tightly and stably bind InlA and block more distinct epitopes on InlA that involved the interaction with E-Cad. On the cellular level, it was confirmed that GA8 effectively blocked LM adhesion with an inhibition rate of 78%. Overall, the robust G4 aptamer-mediated design provides a new direction for the development of inhibitors against other wide-ranging and emerging pathogens.

Sarafloxacin (SAR), one of the most widely used fluoroquinolone antibiotics, is a serious threat to aquatic environments and human health due to its illegal abuse. Herein, we first screened an aptamer (SAR-1) that specifically binds to SAR using capture-SELEX technology. Based on molecular docking technology, SAR-1 was gradually truncated, and a short SAR-1a with better affinity and specificity was obtained. The optimal SAR-1a was further combined with a Pt nanoparticle (Pt NP)- decorated bimetallic Fe/Co-MOF to fabricate a multimode sensing platform for SAR determination. The Fe/Co-MOF@Pt NPs exhibited excellent peroxidase-like activity, which catalyzed the H 2 O 2 -mediated oxidation of 3,3',5,5'-tetramethylbenzidine (TMB), thereby enabling visual detection of SAR. Meanwhile, the generated oxTMB can also produce SERS responses and be used for the SERS detection of SAR. Moreover, the inherent fluorescence property of Fe/Co-MOF@Pt NPs enabled fluorescence detection of SAR. The designed triple-readout aptasensor showed good sensitivity for SAR detection with limits of detection of 0.125 ng/mL (fluorescent mode) and 0.05 ng/mL (colorimetric and SERS mode). The aptamer-based triple-mode sensing platform provided mutual verification of detection results in different output modes, effectively improving the assay accuracy and providing a promising tool for highly sensitive, selective, and accurate determination of SAR in daily life., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Shiga toxin type II (Stx2), the major virulence component of enterohemorrhagic Escherichia coli, is strongly associated with the life-threatening hemolytic uremic syndrome thus posing a substantial risk to food safety and human health. In this work, a dual-mode aptasensor with colorimetric and surface-enhanced Raman scattering was developed for Stx2 specific detection based on noble metal nanoparticles and Raman reporter loaded metal-organic framework (Mn/Fe-MIL(53)@AuNSs-MBA). The Mn/Fe-MIL(53)@AuNSs could catalyze the H 2 O 2 -mediated oxidation of 3,3',5,5'-tetramethylbenzidine (TMB), thereby enabling visual detection. Meanwhile, the SERS signal from MBA can be enhanced by the decorated AuNSs. Under optimal conditions, a linear range of 0.05-500 ng/mL with limit of detection (LOD) of 26 pg/mL was achieved in colorimetric mode and a linear range of 5-1000 ng/mL with LOD of 0.82 ng/mL in SERS mode, in which the dual-mode results complement each other, widening the linear range, increasing the accuracy and reliability of the detection. The method was further applied to the detection of Stx2 in milk with average recovery of 101.1 %, demonstrating its superior potential for bacterial toxin monitoring., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Building multifunctional platforms for integrating the detection and control of hazards has great significance in food safety and environment protection. Herein, bimetallic Fe-Co-based metal-organic frameworks (Fe-Co-MOFs) peroxidase mimics are prepared and applied to develop a bifunctional platform for the synergetic sensitive detection and controllable degradation of aflatoxin B 1 (AFB 1 ). On the one hand, Fe-Co-MOFs with excellent peroxidase-like activity are combined with target-induced catalyzed hairpin assembly (CHA) to construct a colorimetric aptasensor for the detection of AFB 1 . Specifically, the binding of aptamer with AFB 1 releases the prelocked Trigger to initiate the CHA cycle between hairpin H2-modified Fe-Co-MOFs and hairpin H1-tethered magnetic nanoparticles to form complexes. After magnetic separation, the colorimetric signal of the supernatant in the presence of TMB and H 2 O 2 is inversely proportional to the target contents. Under optimal conditions, this biosensor enables the analysis of AFB 1 with a limit of detection of 6.44 pg/mL, and high selectivity and satisfactory recovery in real samples are obtained. On the other hand, Fe-Co-MOFs with remarkable Fenton-like catalytic degradation performance for organic contaminants are further used for the detoxification of AFB 1 after colorimetric detection. The AFB 1 is almost completely removed within 120 min. Overall, the introduction of CHA improves the sensing sensitivity; efficient postcolorimetric-detection degradation of AFB 1 reduces the secondary contamination and risk to the experimental environment and operators. This strategy is expected to provide ideas for designing other multifunctional platforms to integrate the detection and degradation of various hazards.

Arsenic trioxide (ATO) is well known for its inhibitory effects on cancer progression, including lung adenocarcinoma (LUAD), but the molecular mechanism remains elusive. This study aimed to investigate the roles of ATO in regulating LUAD stem cells (LASCs) and the underlying mechanisms. To induce LASCs, cells cultured in an F12 medium, containing B27, epidermal growth factor, and basic fibroblast growth factor, induced LASCs. LASCs stemness was assessed through tumor sphere formation assay, and percentages of CD133+ cells were detected by flow cytometry. The Cell Counting Kit-8 method was used to assess LASCs viability, while reactive oxygen species (ROS) and iron ion levels were quantitated by fluorescence microscopy and spectrophotometry, respectively, and total m6A levels were measured by dot blot. Additionally, LASCs mitochondrial alterations were analyzed via transmission electron microscopy. Finally, the tumorigenicity of LASCs was assessed using a cancer cell line-based xenograft model. Tumor sphere formation and CD133 expression were used to validate the successful induction of LASCs from A549 and NCI-H1975 cells. ATO significantly inhibited proliferation, reduced ZC3H13 expression and total m6A modification levels, and increased ROS and iron ion content, but repressed sphere formation and CD133 expression in LASCs. ZC3H13 overexpression or ferrostatin-1 treatment abrogated LASCs stemness inhibition caused by ATO treatment, and interference with ZC3H13 inhibited LASCs stemness. Furthermore, the promotion of LASCs ferroptosis by ATO was effectively mitigated by ZC3H13 overexpression, while interference with ZC3H13 further promoted ferroptosis. Moreover, si-ZC3H13 promoted ferroptosis and impaired stemness in LASCs, which ferrostatin-1 abrogated. Finally, ZC3H13 overexpression alleviated the inhibitory effects of ATO on LASCs tumorigenicity. Taken together, ATO treatment substantially impaired the stemness of LUAD stem cells by promoting the ferroptosis program, which was mediated by its ZC3H13 gene expression inhibition to suppress m6A medication., Competing Interests: None., (AJCR Copyright © 2024.)

Background: Maillard reaction involves the polymerization, condensation, and other reactions between compounds containing free amino groups and reducing sugars or carbonyl compounds during heat processing. This process endows unique flavors and colors to food, while it can also produce numerous hazards. Acrylamide (AAm) is one of Maillard's hazards with neurotoxicity and carcinogenicity, these effects can trigger mutations and alternations in gene expression in human cells and accelerate organ aging. An accurate and reliable acrylamide detection method with high sensitivity and specificity for future regulatory activities is urgently needed., Results: Herein, we constructed a colorimetric aptasensor with the hybridization of MIL-glucose oxidase (MGzyme)-cDNA and magnetic nanoparticle-aptamer (MNP-Apt) to specifically detect AAm. The incorporation of MB-Apt and AAm released MGzyme-cDNA in the supernatant, took the supernatant out, with the addition of glucose and TMB, MGzyme would oxidize glucose, the resulting •OH facilitated the oxidation of colorless TMB to blue ox-TMB. The absorbance value at 652 nm, which indicates the characteristic absorption peak of ox-TMB, exhibited a proportion to the concentration of AAm. MGzyme avoided the addition of harmful intermediate H 2 O 2 and created an acid microenvironment for the catalytic reaction. MNP-Apt possessed the advantages of high specificity and simplified separation. Under optimal conditions, this method displayed a linear range of 0.01-100 μM with the limit of detection of 1.53 nM. With the spiked analysis data cross-verified by ELISA kit, this aptasensor was proven to specifically detect AAm at low concentrations., Significance: This colorimetric aptasensor was the integration of aptamer and the enzyme-cascade system, which could broaden the applicable range of enzyme-cascade system, break the limits of specific detection of substrates, eliminate the need for harmful intermediates, improve the reaction efficiency, implement the specific detection, whilst enabling the accurate detection of AAm. Given these remarkable performances, this method has shown significant potential in the field of food safety inspection., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Acrylamide (AA) is a heat-processed potent food carcinogen that is widely used in industry, posing a significant risk to human health. Therefore, it is necessary to investigate the toxic effects and mechanism of AA. miR-21 is a representative biomarker during AA-induced carcinogenesis. Here, dual-color aggregation-induced emission nanoparticles (AIENPs) were developed for the detection and simultaneous imaging of AA and miR-21. AIENPs were synthesized by combining aggregation-induced emission (AIE) dyes and a poly (styrene-co-maleic anhydride) (PSMA) amphiphilic polymer modified with hairpin DNA. Upon AA intervention and aptamer recognition, cDNA was dissociated, leading to miR-21 overexpression and initiating the catalytic hairpin assembly cycle. Consequently, fluorescence quenching was observed due to FRET between AIENPs and labeled quenchers. The relative fluorescence intensities of dual-color AIENPs displayed good linear relationships with logarithmic AA and miR-21 concentrations. Moreover, there was a gradual decrease in dual-color AIENP fluorescence as the HepG2 cell concentration of AA (0-500 μM) and stimulation time (0-12 h) increased, making it possible to simultaneously image AA and AA-induced miR-21. The findings of this work are valuable for revealing the cytotoxic mechanism of AA., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Mycotoxins, which are toxic secondary metabolites produced by fungi, are harmful to humans. Mycotoxin-induced contamination has drawn attention worldwide. Consequently, the development of reliable and sensitive detection methods and high-efficiency control strategies for mycotoxins is important to safeguard food industry safety and public health. With the rapid development of nanotechnology, many novel nanomaterials that provide tremendous opportunities for greatly improving the detection and control performance of mycotoxins because of their unique properties have emerged. This review comprehensively summarizes recent trends in the application of nanomaterials for detecting mycotoxins (fluorescence, colorimetric, surface-enhanced Raman scattering, electrochemical, and point-of-care testing) and controlling mycotoxins (inhibition of fungal growth, mycotoxin absorption, and degradation). These detection methods possess the advantages of high sensitivity and selectivity, operational simplicity, and rapidity. With research attention on the control of mycotoxins and the gradual excavation of the properties of nanomaterials, nanomaterials are also employed for the inhibition of fungal growth, mycotoxin absorption, and mycotoxin degradation, and impressive controlling effects are obtained. This review is expected to provide the readers insight into this state-of-the-art area and a reference to design nanomaterials-based schemes for the detection and control of mycotoxins.

Deoxynivalenol (DON) is a mycotoxin secreted by Fusarium species, posing great harm to food safety and human health. Therefore, it is of great significance to study its toxic effects and mechanism. miR-34a is a representative biomarker during the process of DON-induced apoptosis. Herein, a DON-triggered dual-color composite probe was constructed for simultaneous imaging of DON and miR-34a in living cells. The aptamer blocks the recognition sequence of miR-34a to realize DON-triggered cell imaging. The specific binding of DON with its aptamer and HCR induced by miR-34a resulted in the recovery of fluorescence of the dual-color Au NCs. Under the optimal conditions, the correlation between the relative fluorescence intensities of dual-color Au NCs showed good linear relationships with the logarithm of DON and miR-34a concentration, respectively. With the increase in DON concentration (0-20 μg/mL) and stimulation time (0-12 h), the fluorescence of dual-color Au NCs gradually recovered. This dual-color Au NCs composite probe can realize simultaneous detection of DON and miR-34a induced by DON, which is significant for verifying the cytotoxic mechanism of DON.

Herein, a SiO 2 @Ag NPs core/shell nanoparticles were synthesized to fabricate a surface-enhanced Raman spectroscopy (SERS) sensor for the simultaneous determination of histamine (HIS) and tyramine (TYR) based on specific aptamer recognition and ratiometric strategy. SiO 2 @Ag NPs with 4-thiosaminophenol (4-ATP) and Nile blue A (NBA) molecules were used as an internal standard (IS) and labeled with aptamers corresponding to HIS and TYR, respectively. Raman reporter molecules ROX and Cy5 labeled complementary DNA (cDNA) were then hybridized with aptamers to form rigid double-stranded DNA. After the HIS and TYR were captured by their aptamers, resulting in the dissociation of cDNA and separated from the SERS substrate. Therefore, the SERS signal intensity at 1503 cm -1 of ROX and 1358 cm -1 of Cy5 tagged on the terminal of cDNA decreased with the concentration of HIS and TYR increasing, while the SERS signal intensity at 1079 cm -1 of 4-APT and 592 cm -1 of NBA on the substrate remain stable. Thus, the concentrations of HIS and TYR can be determined by the I 1503 /I 1079 and I 1358 /I 592 values, respectively. This sensing strategy achieves a lower detection limit of 0.2 ng/mL for HIS and 0.05 ng/mL for TYR, respectively, demonstrating promising applications in sensitive detection of BAs in animal-derived foodstuff., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Malachite green (MG), as a parasiticide, is widely used in aquaculture to increase the production of the fishery industry. It poses a great danger to both the food system and the human body. In this study, a one-pot reverse microemulsion polymerization was employed to combine the gold nanoclusters (AuNCs) with molecularly imprinted polymers (MIPs) and covalent organic frameworks (COFs) to synthesize an efficient fluorescent hybrid probe (AuNCs@COFs@MIPs) for selective detection of MG. The specific recognition of AuNCs@COFs@MIPs towards MG triggers the fluorescence quenching of AuNCs. The fluorescent response was linearly related to the concentration over the range of 10-150 nmol/L with a limit of detection of 2.78 nmol/L. In addition, the proposed probe was further applied to fish and water samples. A favorable recovery ranged from 97.34 to 101.51 % toward trace amounts of MG indicating its promising application for detecting residue of veterinary drugs., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

A portable paper-based microfluidic aptasensor is established to simultaneously and visually detect zearalenone (ZEN) and ochratoxin A (OTA). The targets at the sample zone can migrate to two detection zones through dual-channels and result in green and blue fluorescence recovery. This is due to the specific recognition by a respective aptamer that destroys fluorescence resonance energy transfer (FRET) from dual-color upconversion nanoparticles (UCNPs) to Cu-TCPP nanosheets. By capturing fluorescent images and analyzing the corresponding RGB value via a smartphone, ZEN and OTA can be analyzed with limits of detection down to 0.44 ng/mL and 0.098 ng/mL in the linear ranges of 0.5-100 ng/mL and 0.1-50 ng/mL, respectively. Satisfactory recoveries are also obtained for ZEN (94.5-103.7 %) and OTA (92.2-106.8 %) in corn flour. With the advantages of simple operation, low sample consumption, and broad adaptability, this promising platform allows for the on-site detection of multiple hazards in food., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier Ltd.)

Deoxynivalenol (DON), a common mycotoxin produced by Fusarium species, poses a great threat to human and animal body. Hence, it is of significance to develop an ultrasensitive and reliable method for DON detection. Herein, a fluorescence and surface-enhanced Raman scattering (FL-SERS) dual-mode aptasensor was designed for the detection of DON based on gold nanoclusters (Au NCs) and silver nanoparticles modified metal-polydopamine framework (Ag NPs/MPDA). In this aptasensor, complementary DNA modified Au NCs (cDNA-Au NCs) was selected as fluorescence probe, and 6-carboxytetramethylrhodamine (TAMRA)-labeled aptamer modified Ag NPs/MPDA (Ag NPs/MPDA-Apt-TAMRA) was employed as SERS probe, in which Ag NPs/MPDA acted as SERS substance and fluorescence quencher, and TAMRA acted as Raman label. The superior binding affinity of the aptamer with DON to cDNA can regulate the fluorescence and Raman signal intensities and realize the quantitative determination of DON. Under the optimal conditions, the aptasensor exhibited a low detection limit of 0.08 ng mL -1 (0.1-100 ng mL -1 ) in FL mode and 0.06 ng mL -1 (0.1-100 ng mL -1 ) in SERS mode. In addition, it was successfully applied for DON detection in wheat flour. We believe that the proposed FL-SERS strategy has a promising application in the detection of mycotoxins., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Thyroid hormone increases energy expenditure. Its action is mediated by TR, nuclear receptors present in peripheral tissues and in the central nervous system, particularly in hypothalamic neurons. Here, we address the importance of thyroid hormone signaling in neurons, in general for the regulation of energy expenditure. We generated mice devoid of functional TR in neurons using the Cre/LoxP system. In hypothalamus, which is the center for metabolic regulation, mutations were present in 20% to 42% of the neurons. Phenotyping was performed under physiological conditions that trigger adaptive thermogenesis: cold and high-fat diet (HFD) feeding. Mutant mice displayed impaired thermogenic potential in brown and inguinal white adipose tissues and were more prone to diet-induced obesity. They showed a decreased energy expenditure on chow diet and gained more weight on HFD. This higher sensitivity to obesity disappeared at thermoneutrality. Concomitantly, the AMPK pathway was activated in the ventromedial hypothalamus of the mutants as compared with the controls. In agreement, sympathetic nervous system (SNS) output, visualized by tyrosine hydroxylase expression, was lower in the brown adipose tissue of the mutants. In contrast, absence of TR signaling in the mutants did not affect their ability to respond to cold exposure. This study provides the first genetic evidence that thyroid hormone signaling exerts a significant influence in neurons to stimulate energy expenditure in some physiological context of adaptive thermogenesis. TR function in neurons to limit weight gain in response to HFD and this effect is associated with a potentiation of SNS output., (© The Author(s) 2023. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Chlorpromazine is a phenothiazine representative drug that can be used to anesthetize and calm animals. However, chlorpromazine excess may lead to residual persistence in edible tissues, which is potentially harmful to human health and animal production. In this work, high affinity and specificity aptamers against chlorpromazine were screened out based on Capture-SELEX. After ten rounds of screening, the candidate aptamers were obtained. The optimal aptamer of CHL-3 was obtained by isothermal titration calorimetry (ITC) and SYBR Green I (SGI) fluorescence-competition methods. The Kd value of CHL-3 was 69.8 ± 9.81 nM. Subsequently, the Uio-66-NH 2 material was prepared, filled with rhodamine 6G (Rho 6G) dye into the pore, and sealed with CHL-3, and fluorescence probes were obtained. The ratiometric fluorescence detection method was established to detect the concentration of chlorpromazine. A linear relationship was obtained in a range of 1-100 nM, with a lower detection limit of 0.67 nM. Meanwhile, a good recovery was shown in spiked food samples, such as eggs and milk. These results indicate that the constructed ratiometric fluorescence strategy can be successfully applied in food detection., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Levamisole (LEV) is a veterinary drug that often remains in animal food. Consuming products containing high levels of LEV will cause a series of harmful reactions to human health. This work describes the Capture-SELEX (Capture-systematic evolution of ligands by exponential enrichment) screening strategy of LEV aptamers, using streptavidin modified agarose beads as a solid phase medium to separate target-bound and unbound ssDNA. The affinity and specificity of candidate aptamers were determined by SYBR Green I (SGI) dye and isothermal titration calorimetry (ITC), in which LEV-5 showed good binding affinity and specificity, and the dissociation constant was 66.15 ± 11.86 nM. Circular dichroism (CD) was used to characterize aptamer conformational changes before and after target binding, including increased helicity and enhanced base stacking. To evaluate whether this aptamer can be used for LEV detection, a colorimetric-surface-enhanced Raman spectroscopy (colorimetric-SERS) dual-mode aptasensor was constructed based on the peroxidase-like activity and SERS effect of AuNPs/Cu-TCPP(Fe) nanosheets. The detection limits of this dual-mode aptasensor for LEV were 5 nM and 1.12 nM, respectively. This aptamer-based method was further successfully used to detect LEV in milk, with recoveries ranging from 94.95% to 111.2%, providing a potential application for the detection of harmful substances in food., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Zeolitic imidazolate framework (ZIF-8) base-aptamer "gate-lock" biomaterial probes have been synthesized for monitoring intracellular deoxynivalenol (DON) and cytochrome c (cyt c) levels. The aptamer and organic fluorescent dye were regarded as a recognition element and a sensing element, respectively. In the presence of DON, the aptamers of DON and cyt c were specifically bound with the DON and induced cyt c, leading to the dissociation of aptamers from the porous surface of the probes. The gate was subsequently opened to release methylene blue (MB) and Rhodamine 6G (Rh6G), and their fluorescence (emission of MB at 700 nm and Rh6G at 550 nm) significantly recovered within 6 h. Cell imaging successfully monitored the exposure of DON and the biological process of cyt c discharge triggered by the activation of the DON-induced apoptosis pathway. In addition, the response between DON and cyt c was observed during the apoptosis process, which is of high significance for the comprehensive and systematic development of mycotoxins cytotoxicity., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

Excessive use of antibiotics in aquaculture severely endangers human health and ecosystems, which has raised significant concerns in recent years. However, conventional laboratory-based approaches regularly required time or skilled manpower. Herein, we propose a point-of-care-testing (POCT) biosensor detection device for the simultaneous determination of multiantibiotics without complex equipment or professional operators. A laser-printed paper-based microfluidic chip loaded with multicolor fluorescence nanoprobes (mCD-μPAD) was developed to rapidly detect sulfamethazine (SMZ), oxytetracycline (OTC), and chloramphenicol (CAP) on-site. These "fluorescence off" detection probes composed of carbon dots (CDs) conjugated with aptamers (donor) and MoS 2 nanosheets (acceptor) (CD-apt-MoS 2 ) were based on Förster resonance energy transfer. Upon the addition of target antibiotics, the significantly recovered fluorescence signal on the μPAD can be sensitively perceived by employing a 3D-printed portable detection box through a smartphone. Under optimal conditions, this μPAD allowed for a rapid response of 15 min toward SMZ, OTC, and CAP with considerable sensitivities of 0.47, 0.48, and 0.34 ng/mL, respectively. In shrimp samples, the recoveries were 95.2-101.2, 96.4-105, and 96.7-106.1% with RSD below 6%. This paper-based sensor opens an avenue for on-site, high-throughput, and rapid detection methods and can be widely used in POCT in food safety.

Background: 24-epibrassinolide (EBR) is a ubiquitous steroidal phytohormone with anticancer activity. Yet the cytotoxic effects and mechanism of EBR on hepatocarcinoma (HCC) cells remain elusive., Methods: Cell counting kit-8 (CCK-8) assay was performed to evaluate cell viability. Real-time cell analysis (RTCA) technology and colony formation assays were used to evaluate cell proliferation. The apoptosis ratio was measured by flow cytometry. Seahorse XFe96 was applied to detect the effects of EBR on cellular bioenergetics. RNA-seq analysis was performed to investigate differences in gene expression profiles. Western blot and qRT-PCR were used to detect the changes in target molecules., Results: EBR induced apoptosis and caused energy restriction in HCC, both of which were related to insulin-like growth factor-binding protein 1 (IGFBP1). EBR rapidly and massively induced IGBFP1, part of which was transcribed by activating transcription factor-4 (ATF4). The accumulation of secreted and cellular IGFBP1 had different important roles, in which secreted IGFBP1 affected cell energy metabolism by inhibiting the phosphorylation of Akt, while intracellular IGFBP1 acted as a pro-survival factor to resist apoptosis. Interestingly, the extracellular signal-regulated kinase (ERK) inhibitor SCH772984 and MAP/ERK kinase (MEK) inhibitor PD98059 not only attenuated the EBR-induced IGFBP1 expression but also the basal expression of IGFBP1. Thus, the treatment of cells with these inhibitors further enhances the cytotoxicity of EBR., Conclusion: Taken together, these findings suggested that EBR can be considered as a potential therapeutic compound for HCC due to its pro-apoptosis, restriction of energy metabolism, and other anti-cancer properties. Meanwhile, the high expression of IGFBP1 induced by EBR in HCC contributes to our understanding of the role of IGFBP1 in drug resistance., Competing Interests: Conflict of interest The authors declare no conflict of interest., (Copyright © 2022. Published by Elsevier GmbH.)

Background/objective: Internalized occupational stigma may develop in physicians as a result of their identification with the public negative labels and stereotypes about them, and then internalization of them as a part of their self-concept. This study aims to develop the Physician Internalized Occupational Stigma Scale (PIOSS) and to examine its reliability and validity., Methods: In study 1, the initial scale was used to investigate 356 physicians. While in study 2, a total of 346 physicians were investigated with the survey tools named the PIOSS, the Career Commitment Scale (CCS), the Workplace Well-Being Scale (WWBS), the Scale for the Doctor with Patient-doctor Relationship (DDPRQ-10), the Intent to Leave Scale (ILS) and the Occupational Disidentification Scale (ODS)., Results: The PIOSS includes 19 items divided into 3 dimensions: label identification, status loss, and career denial. The results of confirmatory factor analysis (CFA) reveal that the three-factor model fitted well ( χ 2 /df=2.574, RMSEA= 0.068, CFI= 0.931, IFI= 0.931, TLI= 0.919, PNFI= 0.762, PCFI= 0.795). The PIOSS total and each dimension scores were significantly negatively correlated with the CCS and the WWBS scores and remarkably positively associated with the DDPRQ-10, the ILS, and the ODS scores. Cronbach's α coefficients for the PIOSS total scale and dimensions ranged from 0.775 to 0.914, and split-half reliability coefficients ranged from 0.801 to 0.931. In addition, the PIOSS exhibited cross-gender invariance., Conclusion: Having good reliability and validity, the PIOSS can serve as a valid tool for the assessment of physician internalized occupational stigma., Competing Interests: The authors report no conflicts of interest in this work., (© 2022 Fan et al.)

With the growing concern of illegal abuse of amantadine (AMD) and its potential harmful impact on humans, detection of AMD has become an urgent food safety and environmental topic. Biosensing is a promising method for this, but the effective recognition of AMD still remains a challenge. Herein, we isolated an aptamer (Am-20) for AMD through a 14-round iterative selection based on capture-SELEX. The preliminary interaction mechanism between AMD and Am-20 was clarified with the help of docking simulations. Facilitated by a base mutation and truncation strategy, an optimized aptamer Am-20-1 with a short length of 62-mer was obtained, which exhibited competitive affinity with a K d value of 33.90 ± 5.16 nM. A structure-switching SERS-based aptasensor based on Am-20-1 was then established for AMD quantification via a binary metal nanoparticle-embedded Raman reporter substrate (AuNRs@ATP@AgNPs). The fabricated strategy showed a wide linear range (0.005∼25 ng/mL) and a low limit of detection (0.001 ng/mL) for AMD determination. We envision that the novel aptamer identified in this study will provide a complementary tool for specific recognition and detection of AMD and could assist in the supervision of illegal abuse of AMD.

To investigate the potential antitumor activity of synthetic triterpenoid, methyl-2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oate (CDDO-Me) in pancreatic ductal adenocarcinoma (PDAC), MTT cytotoxicity assay, and xenograft nude mice assay were performed to evaluate tumor growth in vitro and in vivo. Seahorse XFe96 bioenergetics analyzer was applied to determine aerobic glycolysis and mitochondrial respiration. Western blot and quantitative reverse transcription-polymerase chain reactions are used to detect protein and messenger RNA transcripts of SLC1A5 and metabolic enzymes. We confirmed the strong antitumor activity of CDDO-Me in suppressing PDAC growth. Mechanistically, we demonstrated CDDO-Me induced mitochondrial respiration and aerobic glycolysis dysfunction. We also verified CDDO-Me downregulated glutamine transporter SLC1A5, resulting in excessive reactive oxygen species (ROS) levels that suppressed tumor growth. Moreover, we confirmed that SLC1A5 depletion reduced the ratio of glutathione/oxidized glutathione. We also found CDDO-Me could inhibit N-linked glycosylation of SLC1A5, which promotes protease-mediated degradation. Finally, we confirmed SLC1A5 was significantly overexpressed in PDAC and closely correlated with the poor prognosis of PDAC patients. Our work uncovers CDDO-Me is effective at suppressing PDAC cell growth in vitro and in vivo and illuminates CDDO-Me caused excessive ROS and cellular bioenergetics disruption which contributed to CDDO-Me inhibited PDAC growth. Our data highlights CDDO-Me could be considered a potential compound for PDAC therapy, and SLC1A5 could be a novel biomarker for PDAC patients., (© 2022 Wiley Periodicals LLC.)

We designed a SERS-based method to detect β-lactoglobulin (β-Lg), a major allergen of milk, utilizing aptamers to specifically anchor β-Lg. The Au-Ag nanourchins with excellent Raman enhancement effects were prepared and modified with a β-Lg aptamer as the capture substrate. By taking advantage of the hybridization of aptamer and Raman reporter molecule (6-Carboxyl-X-Rhodamine: ROX)-labeled complementary DNA (cDNA), when ROX is close to Au-Ag nanourchins, the SERS signal is enhanced. In the presence of β-Lg, aptamer binding to β-Lg induces the dissociation of ROX-cDNA from Au-Ag nanourchins, thereby decreasing the SERS signal. Under optimal conditions, the present bioassay provides a wide detection range of 10 ng/mL to 1000 ng/mL with a detection limit of 0.07 ng/mL. In addition, the established SERS sensor can selectively and accurately identify β-Lg with recovery rates of 93.25-107.0% in milk samples. It provides great potential as a sensitive and reliable detection method against the growing threat of allergens., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Aptamers against deoxynivalenol (DON) were selected through capture-systematic evolution of ligands by exponential enrichment. Through isothermal titration calorimetry and fluorimetric assay, aptamer candidate DN-2 demonstrated good affinity to DON with K d value of 40.36 ± 6.32 nM. Accordingly, a Forster resonance energy transfer aptasensor was fabricated by using the aptamer DN-2 combined with AuCu bimetallic nanoclusters as energy donor and MoS 2 nanosheets as energy acceptor. Under the optimal conditions, the fluorescence response was utilized for DON quantitative determination ranging from 5 to 100 ng/mL with a detection limit of 1.87 ng/mL. The practical application of this method was verified in maize flour samples and demonstrated a satisfied recovery of 94.6 ~ 103.1%. The obtained aptamers and their application in DON determination provide a new tool for DON monitoring in various foodstuff., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

Background: Many extracts and purified alkaloids of M. cordata (Papaveraceae family) have been reported to display promising anti-tumor effects by inhibiting cancer cell growth and inducing apoptosis in many cancer types. However, no evidence currently exists for anti-pancreatic cancer activity of alkaloids extracted from M. cordata, including a novel alkaloid named 6‑methoxy dihydrosphingosine (6-Methoxydihydroavicine, 6-ME) derived from M. cordata fruits., Purpose: The aim of this study was to investigate the anti-tumor effects of 6-ME on PC cells and the underlying mechanism., Methods: CCK-8, RTCA, and colony-formation assays were used to analyze PC cell growth. Cell death ratios, changes in MMP and ROS levels were measured by flow cytometry within corresponding detection kits. A Seahorse XFe96 was employed to examine the effects of 6-ME on cellular bioenergetics. Western blot and q-RT-PCR were conducted to detect changes in target molecules., Results: 6-ME effectively reduced the growth of PC cells and promoted PCD by activating RIPK1, caspases, and GSDME. Specifically, 6-ME treatment caused a disruption of OAA metabolism and increased ROS production, thereby affecting mitochondrial homeostasis and reducing aerobic glycolysis. These responses resulted in mitophagy and RIPK1-mediated cell death., Conclusion: 6-ME exhibited specific anti-tumor effects through interrupting OAA metabolic homeostasis to trigger ROS/RIPK1-dependent cell death and mitochondrial dysfunction, suggesting that 6-ME could be considered as a highly promising compound for PC intervention., (Copyright © 2022 Elsevier GmbH. All rights reserved.)

Deoxynivalenol (DON) is a typical mycotoxin in cereals and poses tremendous threats to the ecological environment and public health. Therefore, exploiting sensitive and robust analytical methods for DON is particularly important. Here, we fabricated a CRISPR-Cas12a-mediated luminescence resonance energy transfer (LRET) aptasensor to detect DON by using single-stranded DNA modified upconversion nanoparticles (ssDNA-UCNPs) as anti-interference luminescence labels and gold nanoparticle-decorated Ti 3 C 2 T x MXene nanosheets (MXene-Au) as enhanced quenchers. The DON aptamer can activate the trans-cleavage activity of Cas12a to indiscriminately cut nearby ssDNA-UCNPs into small fragments, which prevents ssDNA-UCNPs from adsorbing onto MXene-Au, and the upconversion luminescence (UCL) remains. Upon the binding of the aptamer with DON, the trans-cleavage activity of Cas12a was suppressed, and the ssDNA-UCNPs were not cleaved and easily adsorbed onto MXene-Au, which caused UCL quenching. Under optimized conditions, the limit of detection was determined to be 0.64 ng/mL with a linear range of 1 - 500 ng/mL. In addition, the sensor was successfully applied to detect DON in corn flour and Tai Lake water with recoveries of 96.2 - 105% and 95.2 - 104%, respectively. This platform achieves a sensitive and specific analysis of DON and greatly broadens the detection range of CRISPR-Cas sensors for non-nucleic acids hazards in the environment and food., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Deoxynivalenol (DON), a mycotoxin that contaminates crops such as wheat and corn, can cause severe acute or chronic injury when ingested by animals or humans. This study investigated the protective effect of ferulic acid (FA), a polyphenolic substance, on alleviating the toxicity induced by DON (40 μM) in IPEC-J2 cells. The experiments results showed that FA not only alleviated the decrease in cell viability caused by DON (p < 0.05), but increased the level of superoxide dismutase (SOD) (p < 0.01), glutathione peroxidase (GSH-Px), (catalase) CAT and glutathione (GSH) (p < 0.05) through the nuclear factor erythroid 2-related factor 2 (Nrf2)-epoxy chloropropane Kelch sample related protein-1 (keap1) pathway, and then decreased the levels of intracellular oxidative stress. Additionally, FA could alleviate DON-induced inflammation through mitogen-activated protein kinases (MAPKs) and nuclear factor kappa-B (NF-κB) pathways, down-regulated the secretion of interleukin-6 (IL-6) (p < 0.0001), interleukin-8 (IL-8) (p < 0.05), interleukin-1β (IL-1β), interferon-γ (IFN-γ) and further attenuated the DON-induced intracellular apoptosis (10.7% to 6.84%) by regulating the expression of Bcl2-associated X protein (Bax) (p < 0.0001), B-cell lymphoma-2 (Bcl-2) (p < 0.0001), and caspase-3 (p < 0.0001). All these results indicate that FA exhibits a significantly protective effect against DON-induced toxicity.

Background: Pancreatic adenocarcinoma (PAAD) is a severe malignant with a 5-year survival rate of approximately 9%. Oleanolic acid is a well-known natural triterpenoid which exhibits pharmacological activities. We previously synthesized a series of oleanolic acid derivatives and evaluated the tumor-suppressive activity of olean-28,13β-lactam (B28) in prostate cancer. However, the detailed mechanism remains to be understood., Methods: The anti-tumor activity of B28 in PAAD was confirmed by RTCA, colony formation assay and flow cytometry. GO and KEGG enrichment analyses were performed to analyze the differentially expressed genes (DEGs) obtained by RNA sequencing. The effects of B28 on cell bioenergetics were evaluated by seahorse analyzer. Lenti-virus packaged plasmids were performed to knockdown or overexpress target genes. Alteration of mitochondrial membrane potential, ROS and GSH/GSSG were measured by corresponding detection kits according to the manufacturer's protocol., Results: We evaluated and confirmed the promising anti-tumor activity of B28 in vitro. RNA-seq profile indicated that multiple metabolic pathways were interrupted in B28 treated PAAD cells. Next, we demonstrated that B28 induces cellular bioenergetics crisis to inhibit PAAD cells growth and induce cell death. We further validated that cell cycle arrest, inhibition of cell growth, cell apoptosis and cell bioenergetics disruption were functionally rescued by ROS scavenger NAC. Mechanistically, we found glutamine metabolism was inhibited due to B28 administration. Moreover, we validated that down-regulation of GLS1 contributes to ROS generation and bioenergetics interruption induced by B28. Furthermore, we elucidated that YTHDF1-GLS1 axis is the potential downstream target of B28 to induce PAAD cell metabolic crisis and cell death. Finally, we also confirmed the anti-tumor activity of B28 in vivo., Conclusions: Current study demonstrates B28 disrupts YTDFH1-GLS1 axis to induce ROS-dependent cell bioenergetics crisis and cell death which finally suppress PAAD cell growth, indicating that this synthesized olean-28,13β-lactam maybe a potent agent for PAAD intervention., (© 2022. The Author(s).)

In the work, a novel filamentou sodium alginate (SA) /ε-polylysine (PL) fiber with excellent mechanical properties and controllable sizes is prepared in an efficient and environmentally friendly manner via continuous pulling of an electrostatically assembled SA/PL composites at the contact interface of aqueous solutions of cationic polyelectrolyte ε-PL and anionic natural polysaccharide SA. The SA/PL fiber exhibits good antibacterial activity, low cytotoxicity, anti-hemolysis, bioadhesion, and environmental friendliness due to its natural raw materials and green preparation process. In vivo experiments have shown that the SA/PL fiber can promote the healing and repair of skin wounds on the backs of mice via resistance to pathogen infection, reduction of inflammation, and anti-allogeneic allergy of the wound. In summary, these results demonstrate that the SA/PL fiber is a green and biosafe multifunctional natural polymer material, with potential applications in suturing wound., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Aptamers are short single-stranded DNA or RNA oligonucleotides isolated from randomized libraries, presenting high affinity and specificity toward targets with similar to antibodies. Recently, aptamers have demonstrated their outstanding application potential ranging from biosensors, bioimaging, and therapeutics due to various advantages including low immunogenicity, ease of large-scale synthesis, low batch-to-batch variation, easily chemical modification, and programmability. However, the current overall success rate of aptamer is far from being satisfactory, and still needs to overwhelm the major obstacle in affinity, specificity, and stability for practical application. The efficient strategy of manipulating the binding performance of aptamers, and improving their performance in practical application is of great significance. Herein, we review the challenges and advances in manipulating the binding performance (e.g., affinity, specificity, and stability) of aptamers to obtain high-quality aptamers by comprehensive analyzing their structure and properties. This mainly includes interfering with the SELEX protocol to obtain excellent parental aptamers, engineering aptamers in post-SELEX process and matching the optimal working microenvironment. Moreover, the perspectives of future direction are also summarized. We hope to provide researchers with alternative strategies for enhancing the performance of aptamers in practical applications and promoting the explosive development of aptamers in related fields., (Copyright © 2022 Elsevier Inc. All rights reserved.)