Objective To investigate the drug resistance phenotype/genotype and virulence gene carrying status, serotype, and sequence typing (ST) of Campylobacter jejuni in Fengtai District in 2024. Methods The drug resistance phenotype was detected by agar dilution method, and serotyping was performed by real-time fluorescence quantitative polymerase chain reaction (PCR). The whole genome sequencing was used to analyze drug resistance genes, virulence genes, and other characteristics. Results Among the 35 Campylobacter jejuni strains analyzed, the antibiotics with the highest resistance rates were nalidixic acid and ciprofloxacin (both 82.86%), followed by tetracycline (74.89%). All strains exhibited a 100.00% sensitivity rate to erythromycin. The multiple drug resistance rate was 77.14%. The predominant drug resistance genes were gyrA-T86I (94.29%) and tetO (74.29%). The most common serotype was HS:2, accounting for 25 strains. A total of 132 virulence genes were detected. There were 12 clonal complexes (CC) and 24 ST types. Conclusion The drug resistance situation of Campylobacter jejuni in Fengtai District is relatively severe, and the drug resistance phenotype is related to specific genetic mutations to some extent. The serotypes are diverse, the virulence genes are complex, and the pathogenic potential is significant, posing a notable risk for inducing Guillain-Barré syndrome (GBS). The high number of ST types indicates substantial genetic diversity.

Emergency Medical Services ; Health Promotion ; Humans ; Life Style ; Nurses ; psychology

Objective To investigate the regulation of IFN-γ to Th17 response in Chlamydia muridarum (Cm) lung infection in mice. Methods A murine model of pneumonia induced by intranasal inoculation of Cm was used for this study. Anti-mouse IFN-γ McAbs were used to neutralize endogenous IFN-γfollowing Cm lung infection. Control group received the same dose of isotype antibody (IgG2a). Mice were sacrificed at day 7 postinfection. Chlamydial growth in the lung was assessed by immunoenzyme technique.IL-17 and IL-23 mRNA expression in the lung was assayed by RT-PCR and the proliferation of IL-17 + CD4 +T cells in the spleen was assayed by intracellular cytokine staining. Results IFN-γ-neutralized mice exhibited serious disease course, include greater body weight loss, higher organism growth and much more severe pathological changes in the lung compared with control mice. The mRNA expression of IL-17 and IL-23 in the lung and the proliferation of IL-17 + CD4 + T cells in the spleen significantly decreased in the IL-17- neutralized mice. Conclusion IFN-γ was protective in Cm lung infection through up-regulating the antigen specific Th17 responses.