OBJECTIVE To analyze resistance and detect plasmid-mediated AmpC genes in Klebsiella pneumoniae.METHODS The susceptibility of the K.pneumoniae to 13 antibiotics was tested by K-B method.Modified three-dimensional extract test was adopted to detect AmpC lactamases in K.pneumoniae.The genotypes of AmpC lactamases were determined by polymerase chain reaction and sequencing.RESULTS Among the 105 isolates,the rate of extended spectrum ?-lactamases(ESBLs) was 41.90%,the rate of AmpC ?-lactamases was 0.95% strains,and the rate of ESBLs and AmpC ?-lactamases was 2.86%.DNA sequence analysis conformed that AmpC lactamases positive isolates were DHA AmpC gene.The resistance rate to penicillins,cephalosporins,?-lactam/?-lactam inhibitors,monobactams,and fluoroquinolones was very high.The susceptibility rate to imipenem was 100.00%.CONCLUSIONS The plasmid-mediated AmpC gene is present in clinically isolated K.pneumoniae.The resistance can be transferred to homologous or different genera of bacteria.

OBJECTIVE To analyze the cause of Acinetobacter baumannii resistance to ?-lactam and the aminoglycoside-modifying antibacterials. METHODS Three-dimensional test was used to analyze and classify the ?-lactamases. Proper primers was used to do PCR and determined by sequencing. RESULTS A. baumannii clinical isolate harbored blaOXA2-23,blaTEM and blaADC genes and aac(3)-Ⅰ,aac(6')-Ⅰb and ant(3″)-Ⅰ aminoglycoside-modifying enzyme genes. CONCLUSIONS An A. baumannii strain which carries TEM,OXA-23,ADC ?-lactams and aac(3)-Ⅰ,aac(6')-Ⅰb,ant(3″)-Ⅰ aminoglycoside-modifying enzyme genes is detected.

Objective To analyze the risk factors of bleeding in elderly patients with peptic ulcer disease (PUD) and its correlation with Helicobacter pylori (Hp) infection, and to provide a theoretical basis for clinical diagnosis and treatment of elderly patients with PUD bleeding. Methods A total of 418 elderly PUD patients admitted to our hospital from June 2019 to June 2020 were selected. The ¹³C-urea breath test was used to determine HP infection. PUD patients were divided into observation group (n=87, bleeding) and control group (n=331, no bleeding). Age, sex, ulcer number, ulcer location, ulcer stage, ulcer diameter and other clinical data were collected. Univariate analysis and logistic regression were used to analyze the risk factors of bleeding in elderly PUD patients. The Forrest classification was used to evaluate the severity of PUD bleeding patients. Pearson correlation analysis was performed between Forrest classification and Hp infection in elderly PUD bleeding patients. Results There were statistically significant differences between the two groups in the course of disease, PUD history, NSAIDs application/ulcer number, ulcer diameter, ulcer location, ulcer stage, Hp infection and NSAIDs application (P<0.05). Multivariate logistic regression analysis showed that the use of NSAIDs, active ulcer, Hp infection and ulcer diameter ≥2 cm were risk factors for bleeding in elderly patients with PUD (P<0.05). The Hp positive rate in Forrest I patients was significantly higher than that in Forrest II and Forrest III patients (P<0.05). The positive rate of Hp in Forrest II patients was significantly higher than that in Forrest III patients. Pearson correlation analysis showed that Hp infection was positively correlated with the severity of peptic ulcer bleeding in the elderly (r=0.512, P<0.05). Conclusion The risk of bleeding from PUD is higher in the elderly, especially in patients with active ulcer, Hp infection and ulcer diameter ≥ 2 cm. In the treatment process of PUD patients, the eradication therapy of Hp should be emphasized, which can reduce the risk of bleeding.