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A "signal-on" photoelectrochemical (PEC) immunosensor for highly sensitive detection of Human Epididymis Protein 4 (HE4), a new serum biomarker of ovarian cancer with small molecular weight, was fabricated by coupling the porphyrin-based metal-organic framework (MOF) nanosphere (nPCN-224) and Nanobody (Nb). To label the Nb, the nPCN-224 with an average size of 160–200 nm was prepared by solvothermal method. The mechanism for the photocurrent generation of nPCN-224 was systematically investigated, showing that the dissolved O 2 in aqueous solution participated in the charge separation and transport during the photoelectric conversion by generating O 2 ˙-, which resulted in a 6-fold enhanced photocurrent by using ascorbic acid as the O 2 ˙- scavenger. Moreover, the inherent structural porosity of nPCN-224 demonstrated advantage for reactant accessibility. Due to the superior properties of nPCN-224, and the high specificity and affinity of Nbs, the immunosensor exhibited a broad detection range from 1.00 pg mL−1 to 10.0 ng mL−1 and a detection limit of 0.560 pg mL−1, lower than most methods reported before. The immunosensor could clearly distinguish ovarian cancer patients in different stages from healthy individuals, and the as-obtained results matched well with those by traditional electrochemiluminescence immunoassay method from the hospital. This work would open a new avenue for PEC immunosensors in clinical diagnostics and evaluation of potential clinical efficacy. Image 1 • A "signal on" immunosensor for HE4 was constructed using MOF nanospheres as PEC probes. • The MOF with high porosity guaranteed the enrichment of O 2 and AA, promoting charge separation. • Nanobodies were used instead of monoclonal antibody considering the small size of HE4. • The sensor can distinguish ovarian cancer patients in different stages from healthy individuals. [ABSTRACT FROM AUTHOR]

Liver fibrosis is a progression of chronic liver disease with lacks effective therapies at present. Schisandrin B (Sch B), a bioactive compound extracted from the traditional Chinese medicine Schisandra chinensis , was reported to benefit liver diseases. This study aimed to investigate the therapeutic effects and molecular mechanisms of Sch B against CCl 4 -induced liver fibrosis in rats. RNA sequencing and transcriptome analysis were performed collaboratively, including analysis of differential gene expression, gene ontology (GO) analysis, pathway analysis and pathway-act-network analysis. The results demonstrated that Sch B effectively alleviated CCl 4 -induced liver damage and fibrosis in rats, as evidenced by improved liver function and decreased extracellular matrix deposition. Furthermore, 4440 (1878 up-regulated, 2562 down-regulated) genes in the model group versus (vs) normal group, 4243 (2584 up-regulated, 1659 down-regulated) genes in Sch B-treated group vs model group were identified as differentially expressed genes (DEGs). Subsequently, GO analysis revealed that DEGs were mainly enriched in metabolism, oxidation-reduction, endoplasmic reticulum stress and apoptosis-related biological processes. Pathway analysis suggested that Sch B up-regulated cytochrome P450 drug metabolism, PPAR signaling pathways, and down-regulated glutathione metabolism pathways. In addition, the regulatory patterns of Sch B on key genes and pathways were also confirmed. In conclusion, our study demonstrated Sch B alleviated CCl 4 -induced liver fibrosis by multiple modulatory mechanisms, which provide new clues for further pharmacological study of Sch B. Image 1 • Schisandrin B (Sch B) effectively ameliorated CCl4-induced liver fibrosis in rats. • Sch B regulated oxidation-reduction, endoplasmic reticulum stress and apoptosis. • CYP450 enzymes and PPAR signaling pathway were the main targets of Sch B. [ABSTRACT FROM AUTHOR]