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Currently, the influence of the tumor microbiome on the effectiveness of immunotherapy remains largely unknown. Intratumoural Fusobacterium nucleatum (Fn) functions as an oncogenic bacterium and can promote tumor progression in esophageal squamous cell carcinoma (ESCC). Our previous study revealed that Fn is a facultative intracellular bacterium and that its virulence factor Fn-Dps facilitates the intracellular survival of Fn. In this study, we find that Fn DNA is enriched in the nonresponder (NR) group among ESCC patients receiving PD-1 inhibitor and that the serum antibody level of Fn is significantly higher in the NR group than in the responder (R) group. In addition, Fn infection has an opposite impact on the efficacy of αPD-L1 treatment in animals. Mechanistically, we confirm that Fn can inhibit the proliferation and cytokine secretion of T cells and that Fn-Dps binds to the PD-L1 gene promoter activating transcription factor-3 (ATF3) to transcriptionally upregulate PD-L1 expression. Our results suggest that it may be an important therapeutic strategy to eradicate intratumoral Fn infection before initiating ESCC immunotherapies. Fusobacterium nucleatum (Fn) is an oncogenic bacterium reported to promote esophageal squamous cell carcinoma (ESCC). Here the authors show that the virulence factor of Fn, Fn-Dps upregulates PD-L1 and that Fn promotes cell death in T-cells, hence, limiting the efficacy of immunotherapy in ESCC. [ABSTRACT FROM AUTHOR]

A method using solvent extraction following a preconcentration of iodine by evaporation was developed for separation of iodine in waters associated with coalbed methane (CBM) for the determination of 129I using accelerator mass spectrometry, for exploration of CBM resources. The 129I/127I ratios in water samples collected in a CBM field have been determined using the developed method to be (1.6–2.4) × 10–11, which are 2–3 orders of magnitudes lower than that of environmental samples in Xi'an, but 2 orders of magnitude higher than the procedure blank of (1.5–2.1) × 10–13, confirming no measurable crossover contamination during sample analysis and slightly input of modern water in the CBM water. [ABSTRACT FROM AUTHOR]

A rapid analytical method for sequential separation and determination of the most significant α- and β-emitting radionuclidic impurities in 99Tc radiopharmaceutical raw material is presented. Successive HTiO co-precipitation steps were first conducted for effective removal of 99Tc to avoid its spectral interference on the determination of β-emitting nuclides by liquid scintillation counting. A sequential chromatographic method was applied for simultaneous separation and purification of actinide and lanthanide isotopes. A series of K99TcO4 solution spiked with known quantities of 238Pu, 239Pu, 241Pu, 237Np, 241Am, 244Cm and 147Pm were analyzed for method evaluation, demonstrating that the method would meet the analytical requirements for radionuclidic impurity evaluation of K99TcO4 raw material. [ABSTRACT FROM AUTHOR]