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Spodoptera frugiperda is a long-distance migratory pest with strong dispersal ability, fast reproduction speed and destructive feeding, so it is difficult to prevent and control. Pyrethroid insecticides are commonly used in pest insects control, And since the voltage-gated sodium channel (VGSC) serves as a major target of pyrethroids, it is important to study this gene for pest control. VGSC is an integral transmembrane protein consisting of approximately 2,000 amino acid residues found in neurons, myocytes, endocrine cells, and ovarian cells and involved in the initiation and propagation of excitable cellular action potentials. In this study, the cDNA sequence of the VGSC was identified from S. frugiperda by rapid amplification of cDNA ends (RACE) which contained an open reading frame of 6,261 bp encoding a protein of 2,086 amino acids. The molecular weight of this protein was predicted to be 236 kDa, and the theoretical isoelectric point was 5.21. A phylogenetic tree constructed based on lepidopteran insects showed that the VGSC of S. frugiperda was most closely relative to that of Spodoptera litura. VGSC is a highly conserved protein with Ion channel conserved structural domains of transmembrane proteins. qPCR showed that the VGSC gene was highly expressed in the epidermis of 2nd instar larvae, and its expression level was low in other tissues, such as the foregut and Malpighian tubules. In addition, VGSC was also detected in the prepupal stage, then gradually increased in abundance after entering the adult stage, peaked at the adult males on the 4th day of pupal stage, and decreased afterwards. The recombinant plasmid of pSumo-mut-VGSC was constructed and induced to express a His tag fused VGSC protein. Polyclonal antibodies were prepared from purified recombinant VGSC protein. The antibody was ELISA-titered, and the western blotting results showed that it specifically recognized VGSC, whether it was recombinant or endogenous protein. These results have laid the foundation for future studies on the physiological function of this gene in the growth and development of S. frugiperda., 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 B.V.)

Background: Selenium supplementation can be used to treat tumors. However, inorganic selenium is highly toxic, and natural organic selenium is extremely rare. Polysaccharides can improve drug bioavailability and targeting. Lentinan is a polysaccharide that has been approved as an anti-cancer drug in Japan and China., Methods: Lentinan, an antitumor polysaccharide extracted from Lentinus edodes, was conjugated with seleninic acid to be transformed into ester (Se-lentinan) and utilized as drug carrier. The enhancement of the anti-tumor effects of Se-lentinan was evaluated by cell viability, cell cycle, migration, and transwell assays and animal xenograft models. The effects of Se-lentinan on the expression levels of epithelial-mesenchymal transition (EMT) markers were determined through immunofluorescence, Western blot, and immunohistochemistry analyses., Results: Se-lentinan inhibited the invasiveness of B16-BL6 and HCT-8 cells by suppressing EMT. In vivo, Se-lentinan significantly inhibited tumor growth and metastasis of the transplanted melanoma and colon cancer cells and showed less toxicity than sodium selenite. Moreover, Se-lentinan reduced the accumulation of selenium in the liver and kidney tissues of mice and exhibited low organ toxicity., Conclusion: The antitumor activity of selenium was enhanced greatly, and its side effects were reduced with the use of lentinan as drug carrier., (Copyright © 2018. Published by Elsevier Inc.)

Spontaneous cerebral spinal fluidotorrhea (SCSFO) is a type of CSF otorrhea without obvious causes including previous trauma, surgery, infection or neoplasm. The etiology of SCSFO remains unclear, the diagnosis can be overlooked because of the untypical clinical features. In this paper, we reviewed etiology, clinical features, diagnosis and therapy of SCSFO from recent relative literatures., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

Multidrug resistance is a major problem in colon cancer treatment. However, its molecular mechanisms remain unclear. Recently, the epithelial-mesenchymal transition (EMT) in anticancer drug resistance has attracted increasing attention. This study investigated whether vincristine treatment induces EMT and promotes multidrug resistance in colon cancer. The result showed that vincristine treatment increases the expression of several ATP-binding cassette transporters in invasive human colon adenocarcinoma cell line (HCT-8). Vincristine-resistant HCT-8 cells (HCT-8/V) acquire a mesenchymal phenotype, and thus its migratory and invasive ability are increased both in vitro and in vivo . The master transcriptional factors of EMT, especially Twist1, were significantly increased in the HCT-8/V cell line. Moreover, the ectopic expression of Twist1 increased the chemoresistance of HCT-8 cells to vincristine and increased the expression levels and promoter activities of ABCB1 and ABCC1. Furthermore, Twist1 silencing reverses the EMT phenotype, enhances the chemosensitivity of HCT-8/ V cells to anticancer agents in vitro and in vivo , and downregulates the expression of ABCB1 and ABCC1. Twist1-mediated promotion of ABCB1 and ABCC1 expression levels plays an important role in the drug resistance of colon cancer cells., Competing Interests: CONFLICTS OF INTEREST The authors declare no conflicts of interest to disclose.