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Hui Li

Publications and source records attributed to Hui Li.

3 recordsLinked to original sources

Emergence of an optrA-positive Enterococcus faecalis ST699 lineage in animal-derived foods in Beijing, China.

Enterococci from animal-derived foods are key reservoirs for antimicrobial resistance (AMR) in the food chain. However, comparative genomic studies investigating the distribution of the oxazolidinone resistance gene optrA among food- and human-derived Enterococci remain limited. This study assessed linezolid-resistant Enterococci from retail meat and healthy humans in Beijing, China (2023-2024). Among 87 isolates, E. faecalis and E. faecium predominated. Food-derived isolates showed broader resistance profiles than human isolates. Fourteen optrA-positive strains were identified, accounting for 92.9% of food isolates. optrA frequently co-localized with erm(A), ant(9)-Ia, and fexA on Tn554-family transposons, suggesting a potentially transferable multidrug resistance module. Notably, an optrA-positive E. faecalis ST699 clone was identified for the first time in Chinese retail meat. This clone formed a distinct lineage and carried a complete Tn554-optrA island. A representative ST699 isolate exhibited enhanced fitness and virulence potential in the Galleria mellonella model. These findings highlight animal-derived foods as important reservoirs of linezolid-resistant Enterococci and provide genomic evidence consistent with their role as potential sources of optrA-mediated resistance. The emergence of a multidrug-resistant E. faecalis ST699 clone with enhanced fitness characteristics underscores the need for continued surveillance of foodborne antimicrobial resistance within the One Health framework.

Enterococcus faecalis

A chromosomal gtrB homolog and dam differentially contribute to dry-heat and high hydrostatic pressure resistance in Salmonella enterica.

Salmonella enterica can persist in low-moisture foods and shows enhanced dry-heat resistance under low water activity, posing significant food safety challenges. However, the genetic basis of extreme dry-heat resistance and its relationship with other processing stresses remain unclear. In this study, twelve S. enterica strains were screened for dry-heat treatment at 60 °C and 80 °C, with S. Infantis CICC21649 identified as the most resistant strain. Comparative genomics and transcriptional analysis identified candidate genes related to envelope integrity and regulation, including gtrB and dam. Deletion of the chromosomal gtrB homolog reduced dry-heat resistance, producing an additional 0.91-log10 reduction relative to the parent strain at 80 °C. Deletion of dam caused broader stress sensitivity, reducing resistance to both dry heat and high hydrostatic pressure, with the stronger phenotype observed under high hydrostatic pressure. Proteomic analysis of the chromosomal gtrB homolog mutant revealed broad alterations in envelope-associated proteins, transport functions, oxidative stress pathways, and central metabolism under dry-heat stress. These findings indicate that the chromosomal gtrB homolog is an important contributor to extreme dry-heat resistance, whereas dam contributes to resistance against both dry-heat and high hydrostatic pressure, likely through a broader regulatory role in stress adaptation. These results reveal distinct structural and regulatory layers underlying stress adaptation in S. enterica and provide practical guidance for low-moisture food processing by highlighting the need to account for strain-dependent and stress-specific resistance during process validation.

Hydrostatic Pressure

Randomized phase-II trial of surufatinib plus FOLFOX/FOLFIRI versus FOLFOXIRI as second-line therapy for metastatic colorectal cancer.

BACKGROUND: Second-line treatment for metastatic colorectal cancer (mCRC) typically involves oxaliplatin- or irinotecan-based doublet chemotherapy with or without anti-angiogenic antibodies. Triplet regimens such as FOLFOXIRI have demonstrated synergy and improved efficacy as first-line therapy. Surufatinib, an oral multi-kinase inhibitor targeting VEGFR1-3, FGFR1, and CSF-1R, may enhance chemotherapy efficacy. We evaluated surufatinib combined with doublet (FOLFOX/FOLFIRI) versus triplet (FOLFOXIRI) chemotherapy as second-line treatment for mCRC. PATIENTS AND METHODS: This multicentre, open-label, randomized phase-II trial used Simon's minimax two-stage design. Eligible patients had mCRC progressing on or within 6 months after first-line doublet chemotherapy. Patients were randomized 1:1 to surufatinib 250 mg once daily plus either mFOLFOX6/FOLFIRI (doublet cohort, selected based on prior regimen) or FOLFOXIRI (triplet cohort). The primary endpoint was objective response rate (ORR). RESULTS: From September 2021 to November 2023, 57 patients were randomized (28 per cohort after one withdrawal). In the doublet cohort, ORR was 35.7% (95% CI: 18.6-55.9), median progression-free survival (PFS) was 5.4 months (95% CI: 3.8-7.0), and median overall survival (OS) was 19.0 months (95% CI: 9.2-28.8). In the triplet cohort, ORR was 39.3% (95% CI: 21.5-59.4), median PFS was 5.8 months (95% CI: 3.3-8.2), and median OS was 10.9 months (95% CI: 6.0-15.8). Grade ≥3 treatment-emergent adverse events occurred more frequently in the triplet (71.4%) versus doublet (57.1%) cohort, with higher rates of treatment delays (89.3% versus 72.0%) and discontinuations (25.0% versus 14.3%). CONCLUSIONS: Surufatinib plus doublet chemotherapy showed encouraging antitumor activity and acceptable tolerability in second-line mCRC, warranting further evaluation in a larger randomized trial. In contrast, surufatinib plus triplet chemotherapy was associated with increased toxicity, more frequent treatment delays or discontinuations, and shorter overall survival; this combination is not recommended for further investigation in this setting.ClinicalTrials.gov: NCT04734249Date of registration: January 31, 2021.

Humans