Objective To evaluate the performance of VITEK 2-Compact GN13 methods for testing imipenem susceptibility of Klebsiella pneumoniae and assess the reliability of its Advanced Expert System (AES).Methods A retrospective study was conducted with a total of 157K. pneumoniae strains, which were isolated from blood and intra-abdominal infections in the First Affiliated Hospital of Nanchang University from 2014 to 2015. Thein vitro minimum inhibitory concentration (MIC) values of imipenem were determined by disc diffusion, VITEK 2-Compact GN13 and broth microdilution methods, respectively. Categorical agreement (CA) rates of disc diffusion and VITEK 2-Compact GN13 methods were determined using broth microdilution as reference method. The genes encoding ESBLs and carbapenemase were screened by PCR and sequencing analysis. The phenotypic confirmatory tests such as modified Hodge test, PCR and DNA sequencing were used to confirm the resistance mechanism and evaluate the reliability of AES in interpreting the imipenem susceptibility of K. pneumoniae.Results Among the 157 isolates, 64 and 8 were identified as resistant and intermediate strains by broth microdilution method, respectively; 52 and 10 were tested as resistant and intermediate strains by disc diffusion method, respectively; 54 and 13 were determined as resistant and intermediate strains by VITEK 2-Compact GN13 method, respectively, while 70 and 3 were judged as resistant and intermediate strains by VITEK 2-Compact GN13 method plus AES validation. The CA of disc diffusion and VITEK 2-Compact GN13 methods compared with broth microdilution method were all higher than 90 %. However, the major error (ME) rate was 3.8 % and very major error (VME) rates were all 0.6 % in imipenem susceptibility testing by VITEK 2-Compact GN13 and disc diffusion. The imipenem susceptibility of 16 strains were modified by the AES, which eliminated 0.6 % VME, but increased major error by 1.3 % and minor error by 1.9 %. Phenotypic confirmatory tests showed that 75 % (12/16) of these strains were validated as producers of both ESBLs and carbapenemase, which was consistent with the result of AES validation. PCR and DNA sequencing analysis proved that 62.5 % (10/16) of these strains produce IMP-4/KPC-2 /NDM-1 and ESBLs.Conclusions Both disc diffusion and VITEK 2-Compact GN13 methods can be used for testing the imipenem susceptibility of K. pneumoniae isolates with reliable and accurate results. Attention should be paid to the possibility of ME and VME when testing imipenem susceptibility. The VME can be avoided by the AES mechanism. However, AES intervention will increase ME and minor error, which may be associated with decreased expression of carbapenemase.

A cadmium column reduction-azo dyes spectrophotometric method based on micro sequential injection lab-on-valve was established for the determination of total nitrogen in seawater. The experimental parameters were optimized, and the interference experiment was carried out. The results showed that the interference of the main components and salinity in sea water could be eliminated by using a series of standard solution prepared by national standard seawater with certain salinity. The concentration of total nitrogen in seawater was linear with the absorbance in the range of 0 . 03-1 . 00 mg/L with a correlation coefficient of 0. 9993. When determining the national standard seawater at nitrogen concentration of 0. 20 mg/L, the relative standard deviation (RSD) was 4. 9%, the detection limit was 0. 010 mg/L, and the recoveries were 99. 5%-101 . 1%. There were not significance differences between the results of this method and national standard method in the t-test analysis. The method is suitable for the determination of total nitrogen in seawater.

OBJECTIVE:To determine the contents of citric acid in fentanyl citrate raw materials and its injection by ion chro-matography. METHODS:The determination was performed on Thermo Dionex IonPacTM AS11-HC column with mobile phase con-sisted of potassium hydroxide (gradient elution) at the flow rate of 1.0 mL/min. The column temperature was 35 ℃,and sample size was 20 μL. The detector was suppressed conductivity detector. RESULTS:The linear range of citric acid were 0.1157-74.05 μg/mL(r=0.9995). The limit of quantitation was 0.1150 μg/mL,and the limit of detection was 0.0400 μg/mL;RSDs of preci-sion,stability and reproducibility tests were all lower than 2.0%;the average recoveries were 99.6%-101.5%(RSD=0.68%,n=9). CONCLUSIONS:The method is environmentally-friendly and simple with good accuracy and precision,and suitable for the contents determination of citric acid in fentanyl citrate raw materials and injection.

Objective To investigate the effect of VPA and molecular hydrogen(H2)on phenotypes of microglia treated with hypoxia. Methods Mouse hypoxic BV2 microglia were treated with VPA or H2. The levels of phenotypic markers of supernatant and cells were detected by ELISA, flow cytometry and real?time PCR,respectively. Results Hypoxia significantly increased mRNA level of M1 marker(iNOS)and reduced mRNA levels of M2 markers(CD206 and TGF?β)in BV2(P<0.05). Besides,the ratio between the mRNA levels of M1 increased(P<0.05). VPA significantly reduced protein level(CD16/32)and mRNA production(iNOS)of M1 markers in hypoxia?treated BV2(P<0.05). The ratio be?tween the mRNA levels of M1 markers and M2 markers(CD16:CD206,CD32:CD206,iNOS:CD206 and iNOS:TGF?β)were also significantly decreased(P<0.05). H2 significantly reduced both protein levels(TNF?α,CD16/32 and iNOS)and mRNA production(iNOS)of M1 markers and increased secretion of M2 marker(IL?10)in hypoxia?treated BV2(P<0.05). The ratio between the mRNA levels of M1 markers and M2 markers(CD16:CD206,iNOS:CD206 and iNOS:TGF?β)were also highly declined(P<0.05). Conclusion Hypoxia can induce microglial cells toward pro?inflammatory phenotype. Both VPA and H2 can inhibit hypoxia?induced inflammatory effect on microglia.

OBJECTIVE:To determine the content of urea in Urea [13C] capsules by high performance cation-exchange chroma-tography (HPCEC). METHODS:The determination was performed on Zorbax 300 SCX column with mobile phases consisting of acetonitrile-0.1% phosphoric acid (20:80,V/V) at the flow rate of 1.0 mL/min. The detection wavelength was set at 200 nm and column temperature was 35 ℃. The sample size was 20 μL. RESULTS:The linear range of urea was 0.0039-1.0030 mg/ml(r=0.9997). The limit of quantitation was 3.918 μg/mL and the limit of detection was 0.975 μg/mL. RSDs of precision,stability and repetitive test were all lower than 2.0%. The recovery ranged 99.3%-101.0%(RSD=0.67%,n=9). CONCLUSIONS:The meth-od is simple,rapid,sensitive and suitable for the content determination of urea in Urea [13C] capsules.

Objective To analyze the institutional cooperation networks of 137 military hospitals in terms of published papers, trends of cooperation and co-authorship in order to guide the cooperation between military hospitals.Methods The institutional cooperation, co-authorship, author-keyword co-occurrence and author-subject co-occurrence in the 137 military hospitals were analyzed with the Thomson data analyzer( TDA) software.Results and Conclusion The institutional coop-eration between military hospitals could be divided into 5 types and were based on the principle of proximity of locations and similiarity of research.The cooperaiton circle with Chinese PLA General Hospital as the center was expanded over time. The institutional cooperation between military and civilian hospitals was also based on the principle of proximity of locations and similiarity of research.Cooperation between productive authors mainly occurred in the same research group but co-au-thorship outside the research group was scarce.The potential competition or cooperation between research fields and authors can be analyzed by comparing co-authorship and author-keyword co-occurrence.

Objective To investigate the episodic memory monitoring in patients with white matter lesions (WML) and explore the relevance of episodic memory disorder and memory monitoring and the possible mechanism.Methods The feeling of knowing-episodic memory (FOK-EM) paradigm was adopted and subsequently administered in 30 WML patients and 30 control participants who were matched in age and educational level.Results Compared with control group (cued recall 4.37 ± 1.59;recognition 8.73 ± 1.05),the episodic memories of WML patients were significantly impaired on the cued recall performance (3.30 ± 1.51,t =2.666,P ＜ 0.05) and recognition performance (7.23 ± 0.77,t =6.306,P ＜ 0.01).Furthermore,the accuracy of FOK judgment (-0.13 ± 0.31),the correct judgment and correct recognition of FOK-EM (23.16％ ±5.96％) and the correct judgment and false recognition of FOK-EM (34.26％ ± 7.65％) in the WML patients group were significantly different compared with the control group (the accuracy of FOK judgment:0.34 ± 0.27,t =6.280,P ＜ 0.01;the correct judgment and correct recognition:35.12％ ± 6.82％,t =7.234,P ＜ 0.01;the correct judgment and false recognition:19.27％ ±6.50％,t =-8.174,P ＜ 0.01).In addition,the correct judgment and false recognition performance were positively correlated with the severity of periventricular lesions and deep white matter lesions in the WMLpatients group (r=0.716,P＜0.01;r=0.598,P＜0.01).Conclusions The WML patients demonstrated an overestimation of their recognition ability of episodic memory.Moreover,this impairment of memory monitoring was correlated with the deficit of executive function caused by the damage of the prefrontal-subcortical circuit,indicating that this mechanism could be an influential factor of episodic memory disorder in WML.

Objective:To explore the effect of shoulder subluxation on the peripheral nerves in the hemiplegic upper limbs of stroke survivors.Methods:Twenty stroke survivors with shoulder subluxation were enrolled. Conduction in their suprascapular, axillary, musculocutaneous, radial, median and ulnar nerves was monitored and needle electromyography was used to monitor activity in the supraspinatus, deltoid, biceps brachii, extensor digitorum, abductor pollicis brevis and abductor digiti minimi muscles of their affected upper limbs at rest. Upper limb and hand function were assessed using the Brunnstrom scale. The rate of change in the amplitude of the compound muscle action potentials (CMAPs) was correlated with the patient′s disease duration, age, and upper limb and hand Brunnstrom stages.Results:Compared with the healthy side, a significant decrease was observed in the CMAP amplitudes of the suprascapular, axillary, musculocutaneous, radial, median and ulnar nerves of the hemiplegic arm, and the latency of the suprascapular and axillary nerves was significantly prolonged. There was no inter-arm difference in the conduction velocity of the musculocutaneous, radial, median and ulnar nerves. The rates of change in the CMAP amplitudes of the suprascapular, axillary and musculocutaneous nerves were significantly higher than those of the radial, median and ulnar nerves. The sensory nerve action potential (SNAP) amplitudes of the median, ulnar and radial nerves on the hemiplegic side were significantly lower than on the healthy side, but there was no significant difference in the sensory conduction velocity between the two sides. On the hemiplegic side, the median nerve had the highest rate of change rate in the SNAP amplitude, followed by the radial and ulnar nerves, but there was no significant difference among them. Nor was there any significant difference in the rate of change in sensory nerve conduction velocity. The muscles of the affected upper limbs had higher potentials in the proximal than that in the distal nerves after shoulder subluxation. The rate of change in the CMAPs was not significantly correlated with a patient′s disease duration, age, or upper limb or hand Brunnstrom stage on the hemiplegic side.Conclusions:Shoulder subluxation after a stroke can cause greater damage to the peripheral nerves in the shoulder and upper arm than to those in the forearm and hand, possibly affecting the recovery of upper limb function.

Objective To compare and analyze the accuracy and safety of robot-assisted and conventional freehand open approach in pedicle screw fixation using meta-analysis.Methods PubMed,Embase,Cochrane,China Biology Medicine,Wanfang and CNKI databases were searched by computer retrieval to identify the relevant literatures published before December1,2016.The qualified literatures were selected according to the preestablished the inclusion criteria and exclusion criteria,and processed for data extraction and quality evaluation.The RevMan 5.3 software was used for the meta-analysis.The relative risk (RR) and 95％ confidence interval (CI) were adopted to represent the effect differences in the dichotomous variable data.The effect difference of continuous variable data was represented by mean difference (MD) or standardized mean difference (SMD).When P＜0.05 and 95％ CI does not contain the value of 1,the difference was considered statistically significant.Results A total of 266 patients were enrolled,including 138 cases of robot-assisted group and 128 cases of conventional freehand open group,in which 1 200 screws were implanted,including 608 screws by robot-assisted system and 592 screws by conventional freehand open approach.The Gertzbein-Robbins grading criteria (grade A to C) were used.The results showed that there was no significant difference in the accuracy of pedicle screw fixation between the robotic-assisted and conventional freehand open approach according to the grading criteria,i.e.grades A (RR =1.07,95％CI:0.82,1.39,I2=46％,P=0.62),grades B (RR=l.56,95％CI:0.86,2.82,I2=0％,P=0.14) and grades C (RR=0.91,95％CI:0.32,2.55,I2=0％,P=0.85).For the two groups,the difference was no statistically significance in the complication rate (RR=0.33,95％CI:0.05,2.17,I2=0％,P=0.25),and in the revision rate (RR=0.53,95％CI:0.10,2.90,I2=0％,P=0.47).The difference was statistically significance in the overall surgical time (MD=20.90,95％CI:5.54,36.26,I2=15％,P=0.008),and in the exposure time (MD=-1.19,95％CI:-1.63,-0.75,I2=15％,P＜0.000 01).The difference was no statistically significance in the distance between screws and facet joint surfaces (SMD=-1.15,95％CI:0.79,1.51,I2=16％,P＜0.000 01).Conclusions Compared with the conventional freehand open approach,the current evidence cannot confirm that the robot-assisted system has significant advantages in the surgical accuracy of pedicle screw fixation and complication rate.The spinal surgical robot-assisted system,as a new technology,has considerable potential for further development and application in spinal surgery.

STUDY DESIGN: A retrospective clinical review. PURPOSE: To describe the incidence of cerebrospinal fluid leakage (CSFL) after thoracic decompression and examine the CSFL predisposing clinical factors. OVERVIEW OF LITERATURE: CSFL is a common complication following thoracic decompression but has not been sufficiently addressed in former studies. METHODS: A cohort of 362 cases of thoracic decompression from February of 2005 to June of 2013 was examined. The case medical records were reviewed and the occurrence of CSFL and the related clinical parameters were noted. The incidence of CSFL for the entire cohort and each surgical approach were described. Besides, the relationship between CSFL and other clinical parameters were assessed, of which odds ratio values of all CSFL-associated parameters were calculated using multivariate logistic regression analysis. RESULTS: The incidence of CSFL for the entire cohort was 32.3%. Different surgical approaches had different incidences of CSFL, and circumferential decompression had the highest incidence. Though many different clinical parameters were related to the occurrences of CSFL, being older than 52 years, having ossification of the posterior longitudinal ligament or having longer operative segments than 3 vertebrae were significant risk factors for CSFL (p <0.05). Besides, surgeries on the mid-thoracic spine had an increased risk of CSFL (p <0.05). CONCLUSIONS: From our analysis, CSFL was a common complication after thoracic decompression with the incidence of up to 32.3%. This study identified the predisposing clinical factors, and spinal surgeons should be aware of these risk factors to reduce its incidence.
Cerebrospinal Fluid Leak* ; Cerebrospinal Fluid* ; Cohort Studies ; Decompression ; Incidence ; Logistic Models ; Longitudinal Ligaments ; Medical Records ; Odds Ratio ; Retrospective Studies ; Risk Factors ; Spine* ; Surgeons