Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in tertiary hospitals in major regions of China in 2022.Methods Clinical isolates from 58 hospitals in China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2022 Clinical &Laboratory Standards Institute(CLSI)breakpoints.Results A total of 318 013 clinical isolates were collected from January 1,2022 to December 31,2022,of which 29.5％were gram-positive and 70.5％were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species(excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi)was 28.3％,76.7％and 77.9％,respectively.Overall,94.0％of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 90.8％of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis showed significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 94.2％in the isolates from children and 95.7％in the isolates from adults.The resistance rate to carbapenems was lower than 13.1％in most Enterobacterales species except for Klebsiella,21.7％-23.1％of which were resistant to carbapenems.Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.1％to 13.3％.The prevalence of meropenem-resistant strains decreased from 23.5％in 2019 to 18.0％in 2022 in Pseudomonas aeruginosa,and decreased from 79.0％in 2019 to 72.5％in 2022 in Acinetobacter baumannii.Conclusions The resistance of clinical isolates to the commonly used antimicrobial agents is still increasing in tertiary hospitals.However,the prevalence of important carbapenem-resistant organisms such as carbapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a downward trend in recent years.This finding suggests that the strategy of combining antimicrobial resistance surveillance with multidisciplinary concerted action works well in curbing the spread of resistant bacteria.

The reference material (RM) of novel coronavirus (2019n-CoV) is a kind of sufficiently homogeneous and stable material including determined 2019n-CoV sequence and quantity information. The international and domestic RM includes in vitro transcribed and genomic RNA RM, pseudovirus and inactivated virus RM, and protein RM. It can be used as a "ruler" for traceability and method validation of testing agent, performance evaluation of 2019n-CoV testing kits, and laboratory proficiency testing. It also can be used as quality control material to ensure accuracy of tests. Furthermore, RMs of 2019n-CoV plays an important role in the international equivalence and international mutual recognition about 2019n-CoV testing.

Objective:To investigate the incidence and risk factors of autonomic reflex dysfunction hypotension in patients with acute spinal cord injury.Methods:A retrospective case control study was made on the data of 191 patients with acute spinal cord injury admitted to Seventh Medical Center of PLA General Hospital from January 2011 to December 2016, including 164 males and 27 females, aged 18-60 years with an average age of 46.4 years. The injury mechanisms of injuries were traffic accidents in 97 patients, high falling injury in 55, heavy pound injury in 30 and fall injury in 9. The injured segments included 98 patients with cervical spinal cord injury, 52 with thoracic spinal cord injury, 19 with lumbar spinal cord injury and 22 with cone injury. According to the American Spinal Injury Association (ASIA), 61 patients were classified as grade A, 52 as grade B, 38 as grade C and 40 as grade D. Autonomic reflex dysfunction hypotension was defined as a systolic blood pressure below 90 mmHg and heart rate below 60 beat/min. There were 35 patients in hypotension group and 156 patients in non-hypotension group. Incidence of autonomic reflex dysfunction hypotension was observed. The data of sex, age, body mass index, injury mechanism, fracture type, spinal cord injury segment, spinal cord injury grade, blood pressure, heart rate, combined injury and length of hospital stay were collected. Univariate analysis was used to observe the correlation between each factor and the occurrence of autonomic reflex dysfunction hypotension, to screen the suspected related factors, and then Logistic regression analysis was used to identify the independent correlation factors related to autonomic reflex dysfunction hypotension.Results:Autonomic reflex dysfunction hypotension was found in patients with acute spinal cord injury at the cervical and thoracic regions. In 98 patients with cervical spinal cord injury, 26 patients (27%) had autonomic reflex dysfunction hypotension; in 54 patients with thoracic spinal cord injury, 9 patients (17%) had autonomic reflex dysfunction hypotension. All of them showed T 5 segment or above injury. Univariate analysis showed significant differences in spinal cord injury segment and spinal cord injury grading between the two groups( P<0.01), but not in gender, age, body mass index, injury mechanism, fracture type, combined injury or not, and length of hospital stay ( P>0.05). Logistic regression analysis showed that spinal cord injury segment( OR=0.185, 95% CI 0.081-0.424) and spinal cord injury grade ( OR=0.108, 95% CI 0.048-0.244) were independent factors related to autonomic reflex dysfunction hypotension ( P<0.01). Conclusions:Spinal cord injury segment and spinal cord injury grading are independently correlated to autonomic reflex dysfunction hypotension. The higher the injury segment is and the severer the injury is, the more likely autonomic reflex dysfunction hypotension is to occur.

Objective To systematically review the effectiveness and safety of pantoprazole ( PAN ) vs. ranitidine (RAN) for patients with gastroesophageal reflux disease (GERD). Methods PubMed,Medline,EMbase,The Cochrane Library and three Chinese literature databases (CNKI,VIP and Wan fang) were retrieveed.Randomized controlled trials (RCTs) which compared the clinical outcomes of PAN group vs. RAN group for GERD were included. Two reviewers independently screened literatures in accordance with the inclusion and exclusion criteria, extracted the data and assessed the methodological quality of included studies.Then,meta-analysis was performed using RevMan 5.2 software. Results A total of 8 RCTs involving 1 590 patients were included.The results of meta-analysis showed that the PAN group was significantly superior to RAN group in terms of the healing rates and the relief rates of chief symptom for GERD of gradeⅠ-Ⅲ. While there was no significant difference in the incidence of adverse events between the two groups [GradeⅠ,RR=1.17,95%CI (0.80,1.70),P=0.43;GradeⅡorⅢ, RR=0.76,95%CI (0.43,1.36);P=0.36]. Conclusion Current evidence indicates that,pantoprazole is more effective than ranitidine for GERD of grade Ⅰ-Ⅲ,but both treatments are safe and well tolerated.

OBJECTIVE:To evaluate the pharmacoeconomics of pantoprazole vs. ranitidine in the treatment of gastricesophagitis reflux disease(GERD). METHODS:Retrieved from PubMed,EMBase,The Cochrane Library,CNKI,VIP and Wanfang database, RCTs about pantoprazole vs. ranitidine in the treatment of GERD were selected until Sept. 2014. Two reviewers independently screened literature in accordance with the inclusion and exclusion criteria,and extracted the data of included studies. Stata 12.0 soft-ware was used to estimate therapeutic efficacy index and cost,and cost-effectiveness analysis was performed with the decision tree model. RESULTS:A total of 7 RCTs were included,involving 1 389 patients. Cost-effectiveness analysis showed that for gradeⅠ-Ⅲ(by Savary-Miller standard)GERD,cost-effectiveness ratios of ranitidine were all lower than those of pantoprazole(gradeⅠ:18.86 vs. 57.93;gradeⅡorⅢ:35.58 vs. 146.13);gradeⅠ,Ⅱ,Ⅲincremental cost-effectiveness ratio(ICER)were 335.53,349.85,349.85. Sensitivity analysis supported this conclusion. CONCLUSIONS:Ranitidine is more economic therapy plan for gradeⅠ-Ⅲ GERD, but its ICER fluctuates greatly. Individual therapy plan should be formulated according to disease condition and economic condition.

Objective To explore the effects of hyperbaric oxygen preconditioning on ischemia-reperfusion inflammatory reaction of rats after skin flap transplantation.Methods Fifty-six Sprague-Dawley rats were randomly divided into 3 groups:a sham ischemia-reperfusion (SH) group,an ischemia-reperfusion (IR) group and a hyperbaric oxygen reconditioning (HBO) group.Both IR group and HBO group were further divided into 3 subgroups,respectively,according to the time points of serum sampling for test post establishment of the IR model of the abdominal pedicle skin flap transplantation.The IR model of the abdominal pedicle skin flap transplantation was established in all the animals except those in the SH group,with those in the HBO group were preconditioned with HBO twice daily for 3 days before the operation.The blood was sampled at 1,3 and 5 day post-operation to test the level of IL-23 using enzyme-linked immunosorbeut assay (ELISA).The survival skin flaps were sampled from all the animals at 3 and 5 days after the operation for histological observation and evaluation.Results The average IL-23 level of HBO 3 d subgroup (17.80 ± 14.78) was significantly lower than that of the IR 3 d subgroup (38.91 ± 12.26).The average histological scores of the IR 3 d and 5 d subgroups,as well as HBO 3 d and 5 d subgroups were (2.66 ±0.44)and (3.2 ±0.53),(1.85 ±0.31) and (2.29 ±0.32),significantly higher than SH group (0.38 ±0.10).Moreover,the average histological score of the HBO 3 d and 5 d subgroups was significantly lower than IR 3 d and 5 d subgroups respectively.Conclusion Hyperbaric oxygen preconditioning can relieve the ischemia-reperfusion inflammatory reaction through reducing the serum level of IL-23 in rats after skin flap transplantation.

Objective To establish a simple and efficient method for developing a keloid model in nude mice with human keloid-derived fibroblasts.Methods Twenty-seven female BALB/c nude mice were randomly divided into five groups with 5,5,5,8 and 4 mice in group A,B,C,D and E respectively.The mice in group A,B and C were inoculated with 0.1 ml of suspension containing human keloid-derived fibroblasts at concentrations of 1.0 × 104,3.0 × 104 and 5.0 × 104 per microliter Matrigel,respectively,at the right axillary fossa.The tumors that formed in one mouse in group C were taken out,and cut into several parts measuring 5 mm × 5 mm × 5 mm in size,which were then subcutaneously transplanted into the right axillary fossa of mice in group D.The mice in group E were subcutaneously injected with 100 μl of Matrigel and served as the control group.The formation of tumor in mice was observed by naked eyes,and the size of tumors was measured until day 30 after tumor formation in group A,B and C as well as after tumor transplantation in group D.Mice were sacrificed on day 30 after tumor formation,and histopathologic examination was performed to analyze histological features of transplanted tumors and pathological changes in visceral organs such as heart,liver,spleen,lung and kidney.Results The tumor formation rate was consistently 100％ in group A,B and C,and the time required for tumor formation was (90.20 ± 3.96),(61.00 ± 2.92) and (39.60 ± 3.20) days in group A,B and C respectively.There was a significant difference in tumor volume on the 30th day after tumor formation between group A,B and C ((288.34 ± 25.29) vs.(1 370.63 ± 105.24) vs.(1 940.98 ± 184.37) mm3,F =138.74,P ＜ 0.05).The size of implanted tumor mass in group D firstly increased,then gradually decreased,but began to continuously increase since the 14~ day,and tumor finally formed in 7 out of 8 mice.There was no evidence of tumor formation in group E.Histopathologic examination showed uniform histological manifestations,which were similar to those of human scar,in tumor tissues from mice in group A,B,C and D.Neither pathological changes nor metastases were observed in visceral organs of these mice.Conclusion Keloid-bearing nude mouse model can be established by subcutaneous inoculation with human keloidderived fibroblasts,or by subcutaneous transplantation of tumor masses of a certain size that have formed in nude mice.

Objective:To explore and study the clinical values of CT and MRI in the diagnosis of spinal trauma. Methods: One hundred patients with spinal trauma in our hospital were selected as the study objects and randomly divided them into 2 groups, 50 cases in each group. The control group was diagnosed by CT, the experimental group was diagnosed by MRI. Results: The efficacy of CT(control group) on fracture line and fracture flat shift was better than experimental group, but in the aspect of spinal cord injury, ligamentous injury and soft tissue injury, experimental group(MRI) was more sensitive than control group(x2=4.0, P<0.05), differences between 2 groups were statistically significant. Conclusion:Every coin has 2 sides, so as to applying CT and MRI in the diagnosis of spinal trauma, but the accuracy to overall spinal trauma of experimental group is higher. Furthermore, it can avoid misdiagnosing with spinal trauma that applying combined CT and MRI, it is worthy of being widely recommended in clinic.

Objective To evaluate the effect of isoflurane preconditioning on inflammatory responses during spinal cord injury (SCI ) in rats .Methods Sixty adult male Sprague-Dawley rats ,weighing 250-300 g , were randomly divided into 3 groups ( n= 20 each ) using a random number table :sham operation group (S group) , SCI group , and isoflurane preconditioning group (I group ) . The animals were anesthetized with intraperitoneal pentobarbital sodium 40 mg/kg .SCI was produced by a weight-drop contusion at the T10 level .The rats inhaled 2% isoflurane for 2 h ,and the model was established at 24 h after the end of isoflurane inhalation in I group . Neurological function was assessed and scored by using the the Basso , Beattie , Bresnahan (BBB ) Locomotor Rating Scale on 7 days after SCI .Five rats in each group were then chosen and spinal cord specimens were obtained and cut into sections which were stained with haematoxylin and eosin for determination of the viable neuron count .Fifteen rats in each group were sacrificed and the spinal cord was removed for detection of nuclear factor kappaB (NF-κB ) and interleukin-1β (IL-1β) expression (by Western blot ) .Results Compared with S group ,BBB score and the number of viable neurons were significantly decreased ,and the expression of NF-κB and IL-1βprotein was up-regulated in SCI group ( P<0.05) .Compared with SCI group ,BBB score and the number of viable neurons were significantly increased ,and the expression of NF-κB and IL-1βprotein was down-regulated in group I ( P<0.05 ) .Conclusion The mechanism by which isoflurane preconditioning protects the spinal cord is related to inhibition of inflammatory responses in rats .

Objective To observe the effects of hyperbaric oxygen (HBO) exposure on the expression of aquaporin-1 (AQP1) and aquaporin-5 (AQP5) in rats with simulated high-altitude pulmonary edema (HAPE).Methods Fifty-six rats were randomly divided into five groups:control (normal),HAPE (high altitude pulmonary edema model),1 HBOT (HAPE model and HBO therapy for 1 time),2 HBOT (HAPE model and HBO therapy twice) and NOT (normal pressure oxygen therapy) groups,and was intervened accordingly.Western blotting and real-time PCR techniques were used to analyze the expression of AQP1 and AQP5 in their lungs.The wet-todry (W/D) weight ratio and morphology of the lungs was also examined.Results The protein and gene expression of AQP1 and AQP5 in the HAPE group decreased significantly compared with the control group.There were obvious differences in the protein and mRNA expression of AQP1 and AQP5 between the 2 HBOT group and the HAPE group and between the 2 HBOT group and the 1 HBOT group.Compared with the control group and the 1 HBOT group,marked lung injury could be seen in the HAPE group.Compared with the NOT group and the 1 HBOT group,lung injury in the 2 HBOT group was relieved significantly.Conclusions HAPE in rats is associated with down-regulation of the expression of AQP1 and AQP5 in the lungs.This down-regulation can be attenuated and lung injury can be alleviated by HBOT.Two sessions of HBOT could be more helpful than one for promoting this improvement.