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Objective To investigate the prevalence and molecular features of Cryptosporidium in captive-bred Mustela putorius furo in Jiangsu Province.. Methods A total of 290 fresh stool samples were collected from a ferret farm in Jiangsu Province on May 2017, and the small subunit rRNA (SSU rRNA) gene of Cryptosporidium was amplified in stool samples using nested PCR assay. The actin, cowp and gp60 genes were amplified in positive samples and sequenced to characterize Cryptosporidium species/genotypes. Results A total of 18 stool samples were tested positive for Cryptosporidium SSU rRNA gene, with a detection rate of 6.2%. Sequence and phylogenetic analyses of SSU rRNA, actin and cowp genes characterized Cryptosporidium isolated from captive-bred ferrets as Cryptosporidium sp. ferret genotype. In addition, gp60 gene was amplified in 10 out of 18 stool samples tested positive for Cryptosporidium. Conclusions Cryptosporidium is widely prevalent in captive-bred ferrets in Jiangsu Province, and Cryptosporidium sp. ferret genotype is the only Cryptosporidium genotype in ferrets.
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Objective:To investigate the therapeutic efficacy of the combination therapy with CD47-based nanoparticles and anti-PD-L1 monoclonal antibody (αPD-L1) for preventing tumor recurrence and metastasis in vivo.Methods:BALB/c mice were used to construct 4T1 tumor-bearing mouse models. The mouse model was treated with the combination therapy to analyze the effects on local tumor recurrence, tumor growth volume, survival time and lung metastasis in the 4T1 mammary tumor-bearing mouse model.Results:The combination therapy could effectively inhibit local tumor recurrence and prolong the survival time of tumor-bearing mice ( P<0.001). Compared with the αPD-L1 group, the combination therapy can increase the expression of cytokines tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) in mouse serum (all P<0.05) and effector memory T cells in mouse spleen ( P<0.001). In addition, the results on the 4T1-Luc mammary tumor-bearing mouse lung metastasis model showed that the combination therapy could effectively inhibit tumor lung metastasis. Conclusions:The results strongly suggested that combination therapy with CD47-based nanoparticles and αPD-L1 can effectively elicit the memory immune response, and prevent tumor recurrence and lung metastasis.
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To increase detection sensitivity and specificity on hepatitis C virus (HCV) is vital for prevention and controlling of the disease. To establish a more reliable detection method for HCV diagnosis, the full gene fragment of ns3 (non-structural protein of HCV) from recombinant plasmid of J6/JFH1 2a was amplified and then connected into the pET-28a prokaryotic expression vector, and the latter was subsequently transformed into Escherichia coli BL21 (DE3) to have the target protein expression. As a result, a protein with a molecular weight of 72 kDa was obtained and visualized in 10% SDS-PAGE. The purified NS3 protein was used as immunogen to inoculate BALB/c mice and the sera was collected after the fourth immunization. The antibody titer of serum is determined to be about 1:256000 with ELISA. Western blotting and indirect immunofluorescence analysis showed that the mouse polyclonal antibody could react specifically with the native NS3 protein in Huh 7.5.1 cells infected with HCV. These findings may provide basis for further preparation of monoclonal antibodies against NS3 and the development of related detection kit.
