Objective To analyze the virulence genes expression and drug resistance situation of type three secretion system (TTSS) of pseudomonas aeruginosa in Zhongshan area to provide a basis for clinical anti-infection treatment .Methods Seventy-six clinically isolated strains of Pseudomonas aeruginosa were collected from the Zhongshan Municipal People′s Hospital from July to September 2016 .Four virulence genes exoU ,exoS ,exoT and exoY were isolated from the strains by PCR .The Vitek2 Compact au-tomatic microbiological identification instrument was used to detect the sensitivity of antibacterial drugs .The enumeration data were processed with chi-square test .Results The detection rates of gene exoS and exoY were highest ,which were 52 .6% (40/76) and 63 .2% (48/76) respectively ;genotype exoU(-)exoS(+ )exoT (-)exoY(+ ) were predominant and accounted for 59 .26% .The positive rates of 4 virulence genes had no statistical difference between the multiple resistant and non-multiple resistant strains of pseudomonas aeruginosa .The resistance rates in the TTSS positive group to 13 kinds of drugs were commonly lower than those in the TTSS negative group ,the difference was statistically significant .Conclusion The geographic difference exists in virulence genes carrier of pseudomonas aeruginosa .The virulence genes carrying situation in both the multiple resistant and non-multiple resistant strains of pseudomonas aeruginosa is similar .

Objective:To establish the reference values of stimulation single fiber electromyography (SFEMG) in orbicularis oculi, and to explore its sensitivity in repetitive nerve stimulation (RNS) negative ocular myasthenia gravis (OMG) patients, and the relationship between jitter and various clinical parameters.Methods:Thirty-two healthy volunteers were included to establish the reference value of normal controls from January 2019 to December 2019. From December 2019 to January 2023, 36 OMG patients with negative RNS were collected. Quantitative MG score (QMGS) was performed, neostigmine test and antibody titers as well as thymus CT results were recorded. One side of the orbicularis oculi muscle was tested with a disposable concentric needle electrode in stimulation SFEMG, and the mean consecutive difference (MCD) value was calculated, which was compared with the average MCD value and upper limit of individual values in normal controls to evaluate whether the jitter was abnormal. Spearman correlation analysis of abnormal mean MCD values with QMGS and antibody titer was conducted.Results:Among the 32 healthy volunteers, there were 13 males and 19 females, the age was (46.8 ±18.7) years, and the MCD was (19.0 ±4.4) μs. The upper limit of the reference value was 27.7 μs for average MCD, and 37.4 μs for 10% individual values. Among 36 OMG patients negative at RNS tests, 20 were male and 16 were female, with a age of (37.2 ±17.0) years. The MCD was (29.9 ±14.7) μs, and Jitter was abnormal in 29 patients (81%). Among them, 20 (20/25) patients were antibody positive, 6 (6/26) patients had thymic hyperplasia, and 7 (7/26) patients had thymoma. The QMGS was 3(2, 4). There were 7 patients (19%) with normal jitter, whose QMGS was 3(2, 4). Among the patients with normal Jitter, 5 (5/5) patients were antibody positive, 2 (2/6) patients had thymic hyperplasia. There was no statistically significant difference in clinical indicators between the two groups of patients with abnormal or normal jitter. There was no significant correlation in antibody titer or QMGS with abnormal mean MCD value. Conclusions:The upper limit of the mean MCD value in the normal controls is 27.7 μs. The upper limit of a single value is 37.4 μs. Its sensitivity for OMG patients with RNS negative is 81%, and the abnormal mean MCD value does not show a significant correlation with various clinical indicators. Abnormal jitter indicates dysfunction of neuromuscular junction transmission, which is an important neuroelectrophysiological indicator for MG patients and is suitable for RNS negative patients. Orbicularis oculi muscle stimulation SFEMG provides a reliable and sensitive electrophysiological means for functional evaluation of neuromuscular junction.