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In recent years, the rapid development of pig farming has led to a large quantity of heavy metal-polluted wastewater. Thus, it was desirable to develop a simple heavy metal detection method for fast monitoring of the wastewater from the pig farms. Therefore, there was an urgent need to develop a simple method for rapidly detecting heavy metal ions in pig farm wastewater. Herein, a simple electrochemical method for simultaneous detection of Cu2+ and Zn2+ was developed and applied to pig farm wastewater. With a glassy carbon electrode and anodic stripping voltammetry, simultaneous detection of Cu2+ and Zn2+ in water was achieved without the need for complicated electrode modification. Furthermore, it was found that the addition of Cd2+ can enhance the response current of the electrode to Zn2+, which increased the signal by eight times. After systematic optimization, the limit of detection (LOD) of 9.3 μg/L for Cu2+ and 45.3 μg/L for Zn2+ was obtained. Finally, it was successfully applied for the quantification of Cu2+ and Zn2+ with high accuracy in pig farm wastewater. This work provided a new and simple solution for fast monitoring of the wastewater from pig farms and demonstrated the potential of electrochemical measurement for application in modern animal husbandry. [ABSTRACT FROM AUTHOR]

Purpose: Merkel cell carcinoma (MCC) is a neuroendocrine carcinoma originating in the skin. Studies are needed to determine the mechanisms of immune escape in patients with MCC, and malignant cell conditions that promote immune evasion. Methods: We used Single-cell RNA sequencing (scRNA-seq) to determine cellular features associated with MCC disease trajectory. A longitudinal multi-omics study was performed using scRNA-seq data of peripheral blood harvested from four-time points. Six major cell types and fifteen cell subgroups were identified and confirmed their presence by expression of characteristic markers. The expression patterns and specific changes of different cells at different time points were investigated. Subsequently, bulk RNA data was used to validate key findings. Results: The dynamic characteristics of the cells were identified during the critical period between benign improvement and acquisition of resistance. Combined with the results of the validation cohort, the resistance program expressed in the relapse stage is mainly associated with T cell exhaustion and immune cell crosstalk disorder. Coinciding with immune escape, we also identified a decrease non-classical monocytes and an expansion of classical monocytes with features of high inflammation and immune deficiency. Conclusion: Changes in cellular status, such as depletion of T cells and dysregulation of B cell proliferation and differentiation, may lead to drug resistance in MCC patients. Meanwhile, the widespread decreased antigen presentation ability and immune disorders caused by deletion of MHC class II gene expression should not be ignored. [ABSTRACT FROM AUTHOR]

Direct interspecies electron transfer (DIET) is essential for maintaining the function and stability of anaerobic microbial consortia. However, only limited natural DIET modes have been identified and DIET engineering remains highly challenging. In this study, an unnatural DIET between Shewanella oneidensis MR‐1 (SO, electron donating partner) and Rhodopseudomonas palustris (RP, electron accepting partner) was artificially established by a facile living cell‐cell click chemistry strategy. By introducing alkyne‐ or azide‐modified monosaccharides onto the cell outer surface of the target species, precise covalent connections between different species in high proximity were realized through a fast click chemistry reaction. Remarkably, upon covalent connection, outer cell surface C‐type cytochromes mediated DIET between SO and RP was achieved and identified, although this was never realized naturally. Moreover, this connection directly shifted the natural H2 mediated interspecies electron transfer (MIET) to DIET between SO and RP, which delivered superior interspecies electron exchange efficiency. Therefore, this work demonstrated a naturally unachievable DIET and an unprecedented MIET shift to DIET accomplished by cell‐cell distance engineering, offering an efficient and versatile solution for DIET engineering, which extends our understanding of DIET and opens up new avenues for DIET exploration and applications. [ABSTRACT FROM AUTHOR]

Direct interspecies electron transfer (DIET) is essential for maintaining the function and stability of anaerobic microbial consortia. However, only limited natural DIET modes have been identified and DIET engineering remains highly challenging. In this study, an unnatural DIET between Shewanella oneidensis MR‐1 (SO, electron donating partner) and Rhodopseudomonas palustris (RP, electron accepting partner) was artificially established by a facile living cell‐cell click chemistry strategy. By introducing alkyne‐ or azide‐modified monosaccharides onto the cell outer surface of the target species, precise covalent connections between different species in high proximity were realized through a fast click chemistry reaction. Remarkably, upon covalent connection, outer cell surface C‐type cytochromes mediated DIET between SO and RP was achieved and identified, although this was never realized naturally. Moreover, this connection directly shifted the natural H2 mediated interspecies electron transfer (MIET) to DIET between SO and RP, which delivered superior interspecies electron exchange efficiency. Therefore, this work demonstrated a naturally unachievable DIET and an unprecedented MIET shift to DIET accomplished by cell‐cell distance engineering, offering an efficient and versatile solution for DIET engineering, which extends our understanding of DIET and opens up new avenues for DIET exploration and applications. [ABSTRACT FROM AUTHOR]

The increasing antibiotic resistance driven by Pseudomonas aeruginosa typically leads to uncontrolled and persistent inflammatory damage, which is primarily attributed to the virulence and biofilms produced by the bacteria. Herein, we present a novel anti-infective drug strategy designed to inhibit the bacterial quorum sensing system, thereby attenuating P. aeruginosa virulence, and modulating inflammation from drug-resistant bacterial infections. We discovered new quorum sensing LasR/LasB inhibitors derived from the structural modification of a ligustilide derivative library. Of these compounds, 5f demonstrated significant inhibitory activity against LasB (LasB-gfp, IC 50 = 8.7 μM) and a moderate inhibitory effect on P. aeruginosa biofilms (IC 50 = 7.4 μM). Through live image analysis in a fluorescent protein–labeled zebrafish larva model, we observed that compound 5f significantly inhibited the migration of macrophages. Moreover, compound 5f effectively attenuated quorum sensing–mediated virulence factors and biofilm formation by P. aeruginosa. It also alleviated the inflammatory response by P. aeruginosa –infected macrophages through the downregulation of mitogen-activated protein kinase and NF-κB signal-transduction pathways. Notably, in vivo experiments, this compound demonstrated marked therapeutic effects in acute lung injury models induced by lipopolysaccharides from P. aeruginosa. These results indicate that compound 5f has the potential to be a novel anti-infective candidate against drug-resistant infections caused by P. aeruginosa. [Display omitted] • A series of ligustilide derivatives were synthesized. • Compound 5f with excellent P. aeruginosa virulence, biofilm, inflammatory inhibitory effect was identified. • 5f significantly attenuated QS-controlled virulence factors, P. aeruginosa biofilm formation, and the inflammatory response in P. aeruginos a–infected macrophages by downregulating MAPK and NF-κB signal-transduction pathways. • Novel potential anti-infective LasR/LasB inhibitor of 5f with superior anti-biofilm, anti-inflammatory, and anti-virulence activities, making it a promising candidate for combating drug-resistant bacterial infections. [ABSTRACT FROM AUTHOR]