Turbulence of gut microbiota metabolites such as short-chain fatty acids (SCFAs) and secondary bile acids is an important factor in the development of diseases. Many polysaccharides are effective on diseases including...
详细信息
Turbulence of gut microbiota metabolites such as short-chain fatty acids (SCFAs) and secondary bile acids is an important factor in the development of diseases. Many polysaccharides are effective on diseases including ulcerative colitis (UC), yet most studies investigating the mechanisms of polysaccharides mainly focused on their effects on gut microbiota composition and SCFAs, and other metabolites of gut microbiota are often neglected. Here, we examined the effects of polysaccharides from Atractylodes macrocephala Koidz. (AMP) on experimental UC induced by dextran sulfate sodium (DSS) and explored underlying mechanisms of AMP by 16S rDNA-based gut microbiota analysis and untargeted fecal and plasma metabolomics. In addition, a multiscale, multifactorial network was constructed to visualize the mechanisms of AMP. The results showed that AMP significantly increased body weight and ameliorated colonic injury in DSS treated mice. AMP also partly restored the perturbed gut microbiota composition induced by DSS. Untargeted fecal and plasma metabolomics showed that AMP can not only modulate the production of SCFAs by gut microbiota, but also the ability to digest food nutrients, metabolism of amino acids and bile acids, production of cadaverine and other metabolites by hosts and gut microbiota. The study demonstrated that, in addition to SCFAs, AMP can extensively modulate the metabolism of gut microbiota and hosts to achieve the therapeutic effects. This study adds new mechanisms of polysaccharides in treating diseases.
Aeromonas veronii is a comorbid pathogen that can infect humans, and animals including various aquatic organisms. In recent years, an increasing number of cases of A. veronii infection has been reported, indicating se...
详细信息
Aeromonas veronii is a comorbid pathogen that can infect humans, and animals including various aquatic organisms. In recent years, an increasing number of cases of A. veronii infection has been reported, indicating serious risks. This bacterium not only threatens public health and safety but also causes considerable economic loss in the aquaculture industry. Currently, some understanding of the pathogenic mechanism of A. veronii has been obtained. In this study, we first constructed the A. veronii TH0426 fis gene deletion strain Delta fis and the complementation strain C-fis through homologous recombination technology. The results showed that the adhesion and invasion ability of the Delta fis strain towards Epithelioma papulosum cyprini (EPC) cells and the cytotoxicity were 3.8-fold and 1.38-fold lower, respectively, than those of the wild-type strain. In the zebrafish infection model, the lethality of the deleted strain is 3-fold that of the wild strain. In addition, the bacterial load of the deletion strain Delta fis in crucian carp was significantly lower than the wild-type strain, and the load decreased with time. In summary, deletion of the fis gene led to a decrease in the virulence of A. veronii. Our research results showed that the deletion of the fis gene significantly reduces the virulence and adhesion ability of A. veronii TH0426. Therefore, the fis gene plays a vital role in the pathogenesis of A. veronii TH0426. This preliminary study of the function of the fis gene in A. veronii will help researchers further understand the pathogenic mechanism of A. veronii.
Immunotherapy has received wide attention in recent years as a new avenue for the effective treatment of cancer. However, due to the lack of detection limit and sensitivity of immune checkpoint molecule (such as Progr...
详细信息
Immunotherapy has received wide attention in recent years as a new avenue for the effective treatment of cancer. However, due to the lack of detection limit and sensitivity of immune checkpoint molecule (such as Programmed cell death 1 ligand 1, PD-L1) in established clinical methods, the immunotherapy evaluation during anti-PD-L1/PD-1 (Programmed cell death receptor 1) treatment is difficult to be guided accurately. In this study, a highly sensitive and maneuverable Surface-Enhanced Raman Scattering (SERS)-based immunoassay platform is developed for the analysis of exosomal PD-L1, a highly potential biomarker for immunotherapy. Excellent detection of exosomal PD-L1 with good linear fit over a wide concentration range is achieved. In addition, the detection and discrimination of exosomal PD-L1 in the peripheral blood of cancer patients and healthy controls are successfully achieved. Moreover, the platform has also been successfully used to distinguish common diseases, cancer, and healthy control (such as liver cancer, liver cirrhosis, and normal individuals). The detection platform can be successfully used for the trace detection of PD-L1 on exosomes, which has excellent potential for clinical development in cancer diagnosis and treatment guidelines. The construction of an immunoassay platform for exosomal Programmed cell death 1 ligand 1 (PD-L1) is based on the Surface-Enhanced Raman Scattering sandwich chip. The detection of exosomal PD-L1 in a wide concentration range is realized. Then the diagnosis of various cancers, as well as the differentiation of liver cancer, liver cirrhosis, and normal individuals, are successfully achieved. image
A rapid and sensitive electrochemical biosensor was constructed to detect Salmonella using invA gene biosensor. The biosensing was based on polyrrole-reduced graphene oxide (PPy-rGO) nanocomposite modified glassy carb...
详细信息
A rapid and sensitive electrochemical biosensor was constructed to detect Salmonella using invA gene biosensor. The biosensing was based on polyrrole-reduced graphene oxide (PPy-rGO) nanocomposite modified glassy carbon electrode (GCE) and signal amplification with horseradish peroxidase-streptavidin biofunctionalized gold nanoparticles (AuNPs-HRP-SA). PPy-rGO was prepared at 60 degrees C by chemical reduction of PPy-functionalized graphene oxide (PPy-GO) that was synthesized by in situ polymerization at room temperature. The detection signal was amplified via enzymatic reduction of H2O2 in the presence of hydroquinone (HQ) using AuNPs-HRP-SA as nanotag. Under optimal conditions, the differential pulse voltametric (DPV) signal from the biosensor was linearly related to the logarithm of target invA gene concentrations from 1.0 x 10(-16) to 1.0 x 10(-10) M, and the limit of detection (LOD) was 4.7 x 10(-17) M. The biosensor can also detect Salmonella in the range of 9.6 to 9.6 x 10(4) CFU mL(-1), with LOD of 8.07 CFU mL(-1). The biosensor showed good regeneration ability, acceptable selectivity, repeatability and stability, which bode well as an alternative method for Salmonella screening. (C) 2019 Elsevier B.V. All rights reserved.
暂无评论