CTCs Detection and Whole-exome Sequencing Might Be Used to Differentiate Benign and Malignant Pulmonary Nodules

Background and objective Low-density computed tomography(LDCT)improved early lung cancer diagnosis but introduces an excess of false-positive pulmonary nodules data.Hence,accurate diagnosis of early-stage lung cancer remains challenging.The purpose of the study was to assess the feasibility of using circulating tumour cells(CTCs)to differentiate malignant from benign pulmonary nodules.Materials and methods 122 patients with suspected malignant pulmonary nodules detected on chest CT in preparation for surgery were prospectively recruited.Peripheral blood samples were collected before surgery,and CTCs were identified upon isolation by size of epithelial tumour cells and morphological analysis.Laser capture microdissection,MALBAC amplification,and whole-exome sequencing were performed on 8 samples.The diagnostic efficacy of CTCs counting,and the genomic variation profile of benign and malignant CTCs samples were analysed.Results Using 2.5 cells/5 m L as the cut-off value,the area under the receiver operating characteristic curve was of 0.651(95%confidence interval:0.538-0.764),with a sensitivity and specificity of 0.526 and 0.800,respectively,and positive and negative predictive values of 91.1%and 30.3%,respectively.Distinct sequence variations differences in DNA damage repair-related and driver genes were observed in benign and malignant samples.TP53 mutations were identified in CTCs of four malignant cases;in particular,g.7578115T>C,g.7578645C>T,and g.7579472G>C were exclusively detected in all four malignant samples.Conclusion CTCs play an ancillary role in the diagnosis of pulmonary nodules.TP53 mutations in CTCs might be used to identify benign and malignant pulmonary nodules.

Probing active species for CO hydrogenation over ZnCr_(2)O_(4) catalysts

Oxide catalysts are increasingly employed for hydrogenation reactions,among which ZnCrOx is a major catalyst for the oxide-zeolite(OXZEO)process and for the hydrogenation of C1 molecules in general.Owing to the complex nature of ternary oxides,the surface and catalytic properties of ZnCr_(2)O_(4) spinel have remained controversial for CO hydrogenation.Combining in-situ Fourier-transformed infrared spectroscopy and X-ray photoelectron spectroscopy,we examined the adsorption and reaction of CO/H_(2) on the ZnCr_(2)O_(4) catalysts,which were pre-treated under oxidative or reductive conditions.The reduced ZnCr_(2)O_(4) catalyst was found to expose more surface sites for CO adsorption/reaction than the oxidized ZnCr_(2)O_(4) catalyst.Exposing the reduced ZnCr_(2)O_(4) to H_(2) at room temperature led to the formation of surface hydride species,which would transform into hydroxyl species at elevated temperatures.The reduced ZnCr_(2)O_(4) surface exhibited much stronger interaction with CO and H_(2) than ZnO and Cr_(2)O_(3).Exposing the reduced ZnCr_(2)O_(4) to the CO and H_(2)(1:1)mixture gas led to the hydrogenation of CO.However,CO was oxidized by the hydroxyl species via the water-gas-shift reaction,whereas the hydrogenation of CO could only be achieved by surface hydride species on the reduced ZnCr_(2)O_(4) to formyl or formate species at 373-473 K.Our study has thus shed light on the active species that control elementary reaction process of CO hydrogenation on complex oxide surfaces.