No abstract

To investigate the molecular epidemiology of Staphylococcus aureus (S. aureus) isolated from patients in the Yellow River Delta region and to construct antibiotic resistance profiles in different genetic backgrounds. Methods: Antibiotics susceptibility testing, staphylococcal protein A (spa) typing and accessory gene regulator (agr) typing were performed for all the 204 strains. Isolates with the positive mecA gene and heterogeneous vancomycin-intermediate S. aureus (hVISA) were subjected to multilocus sequence typing (MLST) and Staphylococcal chromosomal cassettes mec (SCCmec) typing. Results: Thirty-nine MRSA strains were identified by mecA gene. Twenty-two hVISA isolates including 9 MRSA and 13 methicillinsensitive S. aureus (MSSA) strains were confirmed, the rest isolates (n = 182) were vancomycin-susceptible S. aureus (VSSA). 94.9% of MRSA and 63.6% of hVISA belonged to agrI. Fifty-seven distinct spa types including 5 novel types were mainly t309 (30.9%), t078 (11.8%) and t437 (11.8%). Fourteen sequence types (STs) containing 3 new STs were classified into 3 clone complexes (CCs) and 7 singletons among MRSA and hVISA isolates. Most MRSA isolates (87.2%) belonged to type Ⅳ SCCmec. Conclusion:The predominant genotype among MRSA population was ST59-t437-agrI-IVa (53.8%), followed by ST72-t2431-agr I-IVF (15.4%). ST72 and CC5 (ST5/965/7197) were the most common hVISA clones. Both CC59 (ST59/7437) and ST72 clones were resistant to erythromycin and clindamycin among MRSA population. Strains of MSSA with phenotypic hVISA (MS-hVISA) exhibited a striking genetic diversity accompanied by the diversification of drug resistance patterns.

No abstract

This paper expands research on the relationship marketing model of “customer gratitude→repeated purchase intention” by focusing on customers’ psychological and introducing customer psychological ownership, brand attachment, and product attitude as three mediator variables into the SOR theory. The PLS-SEM method is applied to analyze 283 questionnaires. The results are as follows. (1) Customer gratitude is an essential factor for customer psychological ownership, which has a significant positive impact on brand attachment and product attitude. (2) Brand attachment and product attitude are critical factors for consumers’ repeated purchase intention. (3) The mediating effects of customer psychological ownership, brand attachment, and product attitude were further confirmed. This paper can provide references for companies and service personnel on optimizing services and maximizing profits during competition.