N-CDs were prepared with a high fluorescence quantum yield of 35.08%. N-CDs have been employed to detect metronidazole in commercial metronidazole tablets. N-CDs exhibited quick response time, high selectivity and sensitivity, and low cytotoxicity.

Antimicrobial peptides have become important candidates as new antibiotics against resistant bacterial strains. However, the major industrial manufacture of antimicrobial peptides is chemical synthesis with high costs and in relatively small scale. The Ub-tag and SUMO-tag are useful for increasing the yield of enzymes and other proteins in expression system. In this study, antimicrobial peptide A20L (KWKSFLKTFKSAKKTVLHTLLKAISS), a derivative of V13K in the previous study is used as a template to be expressed in different Ub-tag and human SUMO tag systems to compare the prokaryotic expression approaches of antimicrobial peptide. The antibacterial mechanism of action and membrane specificity of A20L was further studied. We fused the Ub and SUMO1/2/3/4 with A20L to construct expression plasmids. Ub-A20L and SUMO1/2/34 gene sequences were inserted into the pHUE plasmids and pET-28b+ plasmids, respectively, to construct pHUE-A20L plasmids and pET-28b+-SUMO1/2/3/4-A20L plasmids. These plasmids were transformed into E. coli Rosetta (DE3) and induced with IPTG to express Ub-A20L and SUMO1/2/3/4 fusion proteins. The recombinant proteins were found in the soluble fraction after being over expressed in E. coli Rosetta (DE3). Antibacterial and hemolytic activities and membrane permeabilization ability of A20L were determined. Peptide structure was also studied by circular dichroism experiments. A20L (KWKSFLKTFKSAKKTVLHTLLKAISS) was successfully expressed by fusion with an ubiquitin tag (Ub-tag) and human SUMO tags (SUMO1/2/3/4-tags). A20L exhibited antimicrobial activity against various Gram-negative and Gram-positive bacteria. Based on the hemolytic activity against human red blood cells, A20L showed good specificity against bacteria. The circular dichroism experiments illustrated that A20L was transferred into an α-helical structure in the presence of hydrophobic environment. The antibacterial mechanism of action and membrane specificity of A20L was further studied using membrane permeabilization experiments and tryptophan fluorescence and quenching experiments in liposomes. The Ub-tag and human SUMO-tags represent good alternatives to chemical synthesis for the industrial production of antimicrobial peptides with low costs and high yields. The antibacterial mechanism of action of A20L was proved as membrane disruption. A20L showed stronger specificity on liposomes mimicking bacterial membrane than those mimicking eukaryotic cell membrane, which is consistent with the biological activity studies.

Nitrogen and boron co-doped carbon dots were synthesized using boric acid and triammonium citrate as precursors. N,B-CDs are effective in detecting both mercury ions and biothiols. The linear detection range of mercury ion and biothiols is 0–150 and 0–100 μmol/L, respectively. The detection limit for mercury ions is 18 nmol/L, and for the three kinds of biothiols, it is 13.42, 23.13, and 28.74 nmol/L, respectively. N,B-CDs have proven effective for detecting both in tap water and in human serum samples. N,B-CDs have low cytotoxicity and can be used for HeLa cell imaging. Beyond their detection capabilities, N,B-CDs also possess antifungal activity, effectively eliminating Cryptococcus neoformans and Candida albicans . The findings indicate that N,B-CDs could be used as multifunctional probes for cellular labeling and hold potential in the development of antifungal drugs.

Alcohol dependence (AD) is a global public health concern with strong genetic characteristics. The purpose of this study was to explore the underlying pathogenic genes and mechanisms associated with AD. This study employed a multi-omics Mendelian randomization approach to identify potential disease-causing genes for AD. Specifically, we integrated transcriptome-wide association studies (TWAS) with summary-data-based Mendelian randomization (SMR) to pinpoint candidate genes associated with AD. Additionally, mediating Mendelian randomization was utilized to investigate the mediating role of the gut microbiota in the relationship between immune cell phenotypes and AD. Two susceptibility genes associated with AD, ADH1C and POLI, were identified a joint analysis of SMR and integrated cross-tissue and single tissue TWAS in European population. A new genetic locus associated with AD, rs62307318, was uncovered through cross-organism TWAS. This finding was further validated using Mendelian randomization and Phenome-wide association analysis. Additionally, Mendelian randomization identified Paceibacteria as a possible mediator between Myeloid DC AC and AD. This study identified two genes closely related to AD and explored the possible pathogenesis of AD, which provides a new insight into the treatment and pathogenesis of AD.

Carbon dots co-doped with nitrogen and sulfur (N,S-CDs) are produced from polyethyleneimine (PEI) and thiourea through a simple one-pot hydrothermal technique. The N,S-CDs demonstrate a significant luminescent emission, achieving a fluorescence quantum yield of 60.88%.The addition of picric acid result in a reduction of the emission. The quenching mechanism is attributed to the inner filter effect. The linear detection range for picric acid is 0–300 μmol/L, with a detection limitation of 28 nmol/L. N,S-CDs also display strong antibacterial activity and low toxicity.This work demonstrates that N,S-CDs possess substantial value in the detection of picric acid as well as in the advancement of antibacterial materials.