Background: Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) is a multifunctional Ig-like cell adhesion molecule that has a wide range of biological functions. According to previous reports, serum CEACAM1 is dysregulated in different malignant tumours and associated with tumour progression. However, the serum CEACAM1 expression in non-small-cell lung carcinomas (NSCLC) is unclear. The different expression ratio of CEACAM1-S and CEACAM1-L isoform has seldom been investigated in NSCLC. This research is intended to study the serum CEACAM1 and the ratio of CEACAM1-S/L isoforms in NSCLC. Methods: The expression of the serum CEACAM1 was determined by enzyme-linked immunosorbent assay. The protein expression and the location of CEACAM1 in tumours were observed by immunohistochemical staining. The CEACAM1 mRNA levels in tumour and normal adjacent tissues were measured using quantitative real-time PCR, and the expression patterns and the rate of CEACAM1-S and CEACAM1-L were analysed by reverse transcription-PCR. Results: Serum CEACAM1 levels were significantly higher in NSCLC patients compared with that from normal healthy controls (P 0.05), the CEACAM1-S and the CEACAM1-S/L (S: L) ratios were significantly higher in tumour than normal tissues (P <0.05). Conclusions: Our data indicated that the serum levels of CEACAM1 could discriminate lung cancer patients from health donors and that CEACAM1 might be a useful marker in early diagnosis of NSCLC. Moreover, our results showed that the expression patterns of CEACAM1 isoforms could be changed during oncogenesis, even when total CEACAM1 in tumour tissues did not show significant changes. Our study suggested that the expression ratios of CEACAM1-S/CEACAM1-L might be a better diagnostic indicator in NSCLC than the quantitative changes of CEACAM1.

Background: Bloodstream infection (BSI) caused by Escherichia coli has become a growing clinical threat due to its high incidence and mortality rates. Despite its significant global health burden, the genomic diversity of E. coli in Shanghai has not been systematically investigated, with ramifications for treatment and prevention. This study aimed to assess the prevalence and genomic epidemiology of E. coli BSI isolates in Shanghai, delineate predominant lineages and their related phenotypic and genomic characteristics, and elucidate the population structure. Methods: A total of 136 E. coli strains were collected from a tertiary hospital in Shanghai between 2023 and 2024. We conducted comprehensive analyses, including multilocus sequence typing (MLST), core genome MLST (cgMLST), clonal complex assignment, serotype prediction, identification of antimicrobial resistance genes (ARGs) and plasmid-borne virulence genes, and plasmid mobility prediction. Results: The predominant clonal complex was CC131 (22.8%), followed by CC14 (14%). The highest resistance rate was observed for ampicillin (85.3%), whereas amikacin (3.7%), ertapenem (2.9%), imipenem (2.9%), minocycline (2.2%), and meropenem (2.2%) retained excellent in vitro activity. High resistance to ciprofloxacin (63.2%) and levofloxacin (62.5%) was observed, primarily mediated by mutations in gyrA (S83L, D87N) and parC (S80I), particularly in ST1193 strains. Plasmid-borne siderophore virulence genes co-occurred as gene modules, the majority of which were located on transferable IncFIB plasmids. However, this trend was not uniform across lineages, with the CC131 clones predominantly carrying mobilizable plasmids, while CC14 clones predominantly harbored non-mobilizable plasmids. Conclusions: Our findings reveal the dynamic genetic diversity of E. coli BSI isolates at a tertiary hospital in Shanghai, highlighting the importance of genomic surveillance and providing valuable insights for infection control.