Comparison of placement of peripherally inserted central catheters using vascular ultrasound guidance system and traditional method in 938 tumor patients / 中华临床营养杂志

Objective To compare the placement of peripherally inserted central catheters(PICC)by using vascular ultrasound guidance system and traditional method.Methods Totally 938 patients undergoing PICC were divided into the traditional method group and the vascular ultrasound system and microintroducer techniques group according to the puncture time.The differences in the one-attempt success rate and the overall success rate of the placement and the incidences of complications were compared between the two groups.Results The one-attempt success rate was 93.01％ in the traditional method group and 98.76％ in the vascular ultrasound system and microintroducer techniques group(P =0.005).The successful rate of PICC placement was 100％.The incidence of complication was 11.29％ in the traditional method group and 2.47％ in the vascular ultrasound system and microintroducer technique group(P =0.000).Conclusion The PICC placement using vascular ultrasound guidance system and microintroducer techniques can increase one-attempt success rate and decrease complications.

Risk Factors and Preventive Measures of External Fixator-related Infections in Orthopedics / 中华医院感染学杂志

OBJECTIVE To analyze the major reasons of wound infection after external fixator application and then introduce management measures to prevent following wound infections. METHODS Totally 542 patients adopting external fixators between May 2005 and May 2007 were retrospectively reviewed. All the external fixator-related infections were inspected and the excretions from these infected wounds were collected to perform bacterial culturing. RESULTS The total infection rate of these 542 patients after external fixator application was 2.77%. Among them, six were infected with the bacteria in distraction osteogenesis group and the infection rate was 8.82%; three were infected in bone un-union and bone defect group and the infection rate was 5.36%; whilest the common fracture-fixing group got the lowest infection rate of 0.39%. CONCLUSIONS Wire-crossing positions are the most frequently infected sites after external fixation and the drug-resisted bacteria are the most commonly detected pathogens. Thus, increasing the stability of fixators, enhancing the infection supervision of operation environment, draining the wound thoroughly and using antibiotics rationally are the most effective managing measures to prevent external fixator-related infections in orthopedics.

Aptamer-based Piezoelectric Quartz Crystal Biosensor / 中华医院感染学杂志

OBJECTIVE To establish an aptamer-based piezoelectric sensor assay to detect human immunoglobulin E (IgE) and acquire the parameters about this kind of biosensor. METHODS Anti-IgE aptamers were immobilized on the gold surface of piezoelectric quartz crystal sensor with biotin-avidin method. The reaction between anti-IgE aptamers and IgE was monitored in time on piezoelectric sensor. Different concentrations of IgE were detected and the calibration curve of IgE was drawn. Non-specific response signals of BSA, IgG and IgE were monitored to show the detecting specificity of aptamer-based sensor. RESULTS For the aptamer-based sensor, the lowest limit of detection was 0.055mg/L and the linear range was 0.1-2.5mg/L. Non-specific signals of this sensor were less than 5% of specific signals of IgE at the same concentration. CONCLUSIONS The aptamer-based piezoelectric sensor can detect 5.5 ng IgE while the non-specific signals are very low. So this aptamer-based sensor is hopeful to be applied to clinical laboratory diagnosis.

Piezoelectric Immunoglobulin Aptamer Biosensor for Determination of IgE / 中华医院感染学杂志

OBJECTIVE A new piezoelectric aptamer biosensor is developed for determination of IgE. The energy converters are 10MHz AT-cut quartz crystals with gold-coated electrodes. The anti-IgE aptamers are immobilized onto the surfaces of crystals gold electrodes by biotin-avidin method. METHODS The standard substance and serum were detected to find the limit of detection and specificity of the biosensor. RESULTS The piezoelectric immunoglobulin aptamer biosensor could complete the detection without nonspecific response. Under the optimized conditions, the experimental results showed that the piezoelectric biosensor had good response to IgE whose frequency shifts were linearly dependent on IgE concentration in different range. The piezoelectric aptamer biosensor had been used to detect IgE in serum, the analytical results given by this method were in satisfactory agreement with those given by chemoluminescence method, its correlation coefficient was 0.9924. CONCLUSIONS Piezoelectric aptamer biosensor for the determination of IgE is of high sensitivity, high specificity, high analysis speed, unnecessary labeling, simple operation, real-time detection, etc. It is suitable for detection of IgE and should be used for clinical detection.

Regeneration Ability of Aptamer-coated Piezoelectric Quartz Crystal Chips / 中华医院感染学杂志

OBJECTIVE To study the optimal reagent for regeneration of aptamer-coated piezoelectric quartz crystal chips and detect storage ability of aptamer-coated chips. METHODS Anti-IgE aptamers were immobilized on the gold surface of piezoelectric quartz crystal biosensor with biotin-avidin method. The reaction between anti-IgE aptamers and IgE was monitored in time on piezoelectric sensor. We tried to regenerate the sensor surface after binding IgE by rinsing the aptamer-coated chips with HCl, NaOH, EDTA, urea and formamide individually. Aptamer-coated chips were stored in PBS with 0.1% sodium azide and the stored chips were used to detect IgE in 35 days. RESULTS Of the five reagents, EDTA was the best one for regeneration of aptamer-coated chips and the sensor could retain 91.5% of the original detecting signals after five regeneration cycles. Moreover, the aptamer-coated chips could be stored in the binding buffer for 21 days without obvious loss of activity. CONCLUSIONS Compared with antibody-based piezoelectric sensor, aptamer-based sensor has lower cost, more regeneration cycles and longer time for the storage of chips. This series of experiments shows the superiority of aptamer detection.

Isolation and Identification of Non-fermenting Bacteria and Their Antibiotic Resistance Analysis / 中华医院感染学杂志

OBJECTIVE To investigate the distribution and resistance of non-fermenting bacteria isolated from(patients) in 2005 and offer a basis for the treatment of bacterial infection.METHODS The isolated bacteria were(identified) with API identified test(API Inc,France) and Kirby-Bauer(K-B) test used for the antibiotics(susceptivity) test.The data were analyzed by using WHONET-5 software.RESULTS Totally 604 strains of non-fermenting bacteria were isolated from the 2908 pathogenic strains.The most common bacteria were Pseudomonas aeruginosa(52.32%),followed by Stenotrophomonas maltophilia(14.07%) and Acinetobacter baumannii((13.74%)).76.32% of non-fermenting bacteria were isolated from the sputum.These bacteria had various(resistances) to all detected antibiotics.CONCLUSIONS Non-fermenting bacteria have high isolation rate and(multi-drug) resistance,so antibiotics should be used correctly under the guidance of antibiotic susceptibility testing.

Immobilization methods for probes of aptamer-based piezoelectric quartz crystal sensor / 第三军医大学学报

Objective To compare 2 methods to immobilize probes on the surface of gold membrane and select the better one for aptamer immobilization of aptamer-based piezoelectric quartz crystal sensor. Methods Anti-IgE aptamers were immobilized on the gold surface of piezoelectric quartz crystal sensor with thiol method or biotin-avidin method. The changes of frequency were compared in reactions with different concentrations of IgE. Results Biotin-avidin method obtained higher frequency changes in the reactions of IgE, lower limit of detection and wider liner range than thiol method. For biotin-avidin method, there was significant linear correlation between frequency changes and the concentration of IgE with the correlation coefficient of 0.994 5. Conclusion The thiol method which is proved effective for probe immobilization on gene sensor is unfit for aptamer immobilization. Biotin-avidin method has a better ability to immobilize probe on the surfaces of aptamer-based piezoelectric quartz crystal sensor.