Preliminary detection of alanine aminotransferase before blood donation / 中国输血杂志

【Objective】 To explore the optimized strategy of alanine aminotransferase(ALT) screening before blood donation, in order to reduce the waste of blood resources. 【Methods】 The blood donation scrapping of one blood center in Chongqing from January to April 2020 was analyzed retrospectively. The correlation between ALT test results by dry chemistry method and rate method in 500 blood donors, with ALT level close to the limit, was analyzed, and the abnormal rates of retest were stratified by initial results of ALT dry chemical method. 【Results】 Among blood donors enrolled in this study, the rate of ALT abnormality(0.89%, 43/4 846)was significantly higher than that of HBV (0.25%, 12/4 846), HCV (0.43%, 21/4 846) and HIV (0.19%, 9/4 846)(P<0.05). For the samples with pre-donation ALT close to the limit (40 U/L≤ALT≤50 U/L), a weak correlation between the results of dry chemistry method and rate method was observed, with correlation coefficient at 0.33 (P<0.05). The abnormal rates in retest were significantly higher in 45 U/L≤ ALT ≤50 U/L (10.7%, 22/206) group than that in the ALT < 45U/L group(P<0.05). 【Conclusion】 The ALT limit before blood donation should be set to 45 U/L. For blood donors with ALT within the range of (45~50) U / L, blood donation should be deferred until they passed retests by rate method.

The mechanism of metformin induced human choriocarcinoma cell line JAR apoptosis / 国际检验医学杂志

Objective To investigate the possible mechanism of metformin on apoptosis of human chorio-carcinoma cell.Methods The human choriocarcinoma cell line JAR was selected and divided into control and metformin groups(final concentrations were 5,10,20,40 and 80 mmol/L).Confocal microscope was adopted to detect cell apoptosis after 48 h treatment.The mRNA and protein expression of AMPK,p-AMPK,mTOR, Caspase-3,Bcl-2 and Bax were measured by Real-time PCR and Western blot respectively.Results Compared with the control group,apoptosis rate of JAR cells in the metformin group(final concentration was 40 mmol/L)was remarkably increased.Metformin activated AMPK by phosphorylation and inhibited mTOR pro-tein expression,meanwhile mRNA and protein expression levels of Caspase-3 and Bax were significantly in-creased,but Bcl-2 mRNA and protein expression were significantly decreased.Conclusion Metformin induces the JAR cells to generate apoptosis by the AMPK/mTOR pathways and Caspase-3,Bcl-2/Bax pathways simaltaneously.

Teaching practice of patent application for scientific research of the medical postgraduates / 中华医学教育探索杂志

To enhance the scientific research participation of the medical postgraduates, and pro-mote core competitiveness of the medical colleges, based on analysis of the necessity of patent application in medical colleges postgraduate, we constructed the teaching teams including the medical professors, patent engineers, graduate teaching manager, and science and technology managers. The problem-based learning (PBL) and case-based learning (CBL) as teaching methods were used in practice. The patent courses included the reference search and analysis, basic knowledge of patent law, and patent application training module were constructed; and the teaching effect were evaluated and optimized through the scores of the patent basic theory test, research output, and the training of the patent application. The patent course of the medi-cal postgraduates provides a reference for cultivating the compound talents have scientific research innova-tion and patent application capability.

The exploration and practice of practice teaching for laboratory medicine students / 中华医学教育探索杂志

With the goal of practice teaching for laboratory medicine students, we focus on culti-vating students' clinical thinking and scientific thinking through setting up reasonable teaching task and designing the scientific graduation thesis, and try to develop a novel practice teaching mode for laboratory medicine students. Therefore, we do exploration and practice in the following aspects: orientation training, clinical practice, medical ethics education, clinical communication ability, and scientific research design, hoping to improve students' research thinking ability and innovation ability. Through actual operation and graduation thesis writing, we try to help students to establish and improve their clinical thinking ability and innovation ability.

Exploration of the course construction of clinical biochemistry under the new medical model / 中华医学教育探索杂志

Clinical biochemical test course construction in the new medical model, first of all, requires a combination of subject characteristics of the course, and proceeds with the improvement from the teaching methods and evaluation system. Secondly, we should cultivate students' doctor-patient communication skills and humanities quality in the teaching process. Finally, we should establish the effective clinical biochemical test teaching mode to achieve both teaching and learning.

Effects of Th1 and Th2 cytokines on the phagocytosis of Mycobacterium tuberculosis by human neutrophils / 中华微生物学和免疫学杂志

Objective To establish a flowcytometry method for detecting phagocysis of Mycobacterium tuberculosis(Mth) by the human peripheral blood neutrophils( PMNs), and to explore the effects of Thl and Th2 cytokine on phagocytotic activity of PMNs. Methods By using acid-fast staining the phagocytosis of Mtb by human neutrophil was observed by microscopy, and the phagocytosis of FTTC labeled Mtb by human neutrophils was detected under confocal microscope. The whole fresh peripheral blood of healthy adults was incubated with FTTC labeled Mtb and the phagocytosis were measured by flow cytometry. The altered phagocytosis of FTTC-Mtb by neutrophils pretreated with IL-2, IFN-γ, GM-CSF or IL-4 were measured. Results Human peripheral blood neutrophils activity of Mtb phagocytosis was observed by acid-fast staining and confocal microscope. The percentage of phagocytosis of Mtb was dependent on the time of incubation with Mtb. The percentages were 47% at 5 min and reached plateau about 66% ～72% at 15 min to 20 min.Pretreatment with different concentrations of IL-2 or IFN-γincreased the phagocytosis of Mtb by 76.7% and 75.2%, respectively; but pretreatment with IL-4 decreased the phagocytosis by 31.7%. Conclusion IL-2and IFN-γcan increase phagocytosis of Mth by neutrophils; while IL-4 can reduced neutrophil activity of phagocytosis of Mtb by human neutrophils, and demonstrate that Th1/Th2 type cytokins involve in regulating the acitvities of neutrophils anti-Mtb infection.

Surveillance of Antimicrobial Resistance and Classification in Non-fermenting Bacteria Isolated from Lower Respiratory Tract for 3 Consecutive Years / 中华医院感染学杂志

OBJECTIVE To investigate the distribution and resistance of non-fermenting bacteria isolated from our hospital and offer the basis for the treatment of bacterial infection.METHODS Totally 2177 strains of non-fermenting bacteria were isolated from clinical sputum samples between Jan 2006 and Dec 2008.All of the isolated bacteria were identified with API identified test(API Inc,France) and Kirby-Bauer(K-B) test used for the antibiotics susceptive test.RESULTS From them the most common bacteria were Pseudomonas auruginosa(34.9%),followed by Acinetobacter baumannii(28.4%) and Stenotrophomonas maltophilia(11.4%).These bacteria had various resistances to the tested antibiotics.CONCLUSIONS Non-fermenting bacteria have high isolate rate and multi-antibiotic resistance,so antibiotics should be correctly used under the guidance of antibiotic susceptibility test.

Isolation and Characterization of Bacteriophage for Klebsiella pneumoniae / 中华医院感染学杂志

OBJECTIVE To characterize bacteriophage isolated from sewage with indicator of Klebsiella pneumoniae subsp pneumoniae.METHODS Bacteriophage was isolated from sewage by double-layer agar plate method,identified lytic or lysogenic capacity by induced methods of ultraviolet ray and mitomycin C,performed one-step growth experiments,decided the optimal multiplicity of infection,and its structure was observed with electron microscope.RESULTS The study found a strain of bacteriophage against the K.pneumoniae subsp pneumoniae.The phage had a head of 180 nm in diameter and a tail of 210 nm in length.The plaque was transparent and 4-7 mm in diameter.the optimal multiplicity of infection was 4,latent period was 35 min and burst period was 40 min,the average burst size was about 94 PFU/cell.CONCLUSIONS The isolated bacteriophage belongs to Stylovinidae,and it is a lytic bacteriophage with narrow host spectrum.Moreover,it is only sensitive to a part of K.pneumoniae subsp pneumoniae and a few of Escherichia coli strains.

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.

Identification and Drug Sensitive Test for Foot Fungi / 中华医院感染学杂志

OBJECTIVE To explore the changes in foot fungus mobility and its drug resistance for further etiology investigation and clinical treatment. METHODS Sabourand′s agar culture medium was used to culture fungi, ID identification strip was employed to identify the fungi and drug sensitive test was performed by disk diffusion test. RESULTS The incidence of Trichophyton rubrum infection was the highest (79.1%). The isolated fungi were relatively sensitive to amphotericin B (AMB, 98.9%) and itraconazole (ITC, 98.0%), and resistant to 5-fluorocytosine (5-FC, 22.1%). CONCLUSIONS Detection technique of fungal infection should be improved and anti-fungal medicine should be used reasonably according to the results of drug sensitive test so that the fungal infection, especially fungi-resistant infection could be reduced.

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.

Experimental studies of carcino-embryonic antigen immunosensor based on piezoelectric resonate technology of quartz crystal / 生物医学工程学杂志

In order to construct a new type of piezoelectric quartz immunosensor for the determination of carcino-embryonic antigen (CEA), the sensor detection pools were consisted of plastic loops and crystals that were 10 MHz quartz AT-cut with gold coated electrodes and the immobilization of the monoclonal antibody against CEA onto gold electrode surface of the quartz crystal was accomplished via Thiol method. Then the immunosensors were used in clinical laboratory. The experimental results showed that the piezoelectric immunosensor had good response to CEA, the frequency shifts were linearly dependent on CEA concentration in the range of 1.56 to approximately 50.00 ng/ml, other antigens such as alpha fetoprotein (AFP), prostate specific antigen (PSA), human chorionic gonadotropin (hCG) did not interfere with the sensor's response. The results obtained from this method were in satisfactory accordance with those obtained by radio immunoassay(P>0.05), The correlation coefficient was 0.90. Piezoelectric immunosensor for determination of CEA has the advantage of high sensitivity, high specificity, unnecessary labeling, simple performing, rapid analysis, low cost, real-time detection and repeated use, etc. It can be used for detecting serum CEA in clinical laboratory.

Piezoelectric Immunoglobulin Microarray Immunosensor / 中华医院感染学杂志

OBJECTIVE To develop new 2?5 type of piezoelectric immunoglobulin microarray immunosensor for determination of immunoglobulin.The energy converters are 10MHz AT-cut quartz crystals with gold-coated(electrodes).The monoclonal antibodies of immunoglobulin are immobilized onto the surfaces of crystals gold(electrodes) by staphylococcal protein A(SPA).METHODS The standard substance and serum were detected to find the detection time,temperature and specificity of the immunosensor.RESULTS The piezoelectric quartz(crystal) immunoglobulin microarray immunosensor could complete the detection in 15 min without nonspecific(response).Under the optimized conditions,the experimental results showed that the piezoelectric immunosensor had good(response) to immunoglobulin whose frequency shifts were linearly dependent on immunoglobulin (concentration) in different range.The piezoelectric microarray immunosensor had been used to detect(immunoglobulin) in serum,the analytical results given by this method were in satisfactory agreement with those given by traditional (immunoassay),with correlation coefficient of 0.94,0.94,0.94,0.92 and 0.91.(CONCLUSIONS) Piezoelectric microarray immunosensor for the determination of immunoglobulin is of high(sensitivity),high specificity,high analysis speed,unnecessary labelling,simple operation,real-time detection,(repeated) use,etc.It is suitable for (detecting) of immunoglobulin and should be used for clinical detection.

Immobilization of Antibody on Piezoelectric Immunoglobulin Immunosensor / 中华医院感染学杂志

OBJECTIVE To develop a new type of piezoelectric immunoglobulin microarray immunosensor for(determination) of immunoglobulin.METHODS The energy converters were 10MHz AT-cut quartz crystals with gold-coated electrodes.The monoclonal antibodies of immunoglobulin were immobilized onto the surfaces of(crystals) gold(electrodes) by SPA to study the best immobilization yield of the antibodies at different condition.Gold-(protein) A complex was highly stable and was believed to be Van der Waals in nature.We did experiments to find the best temperature-time condition about the binding of SPA and the gold surface and to explore the influence(about) the immobilization of antibody by the concentration and the pH of the antibody solution.RESULTS At the same antibody concentration, it had the highest immobilization yield of SPA at a low-temperature-long-time(combination).The most immobilization yield was obtained at the 5mg/ml concentration of antibody solution.The optimum pH for antibody immobilization was 7.2.CONCLUSIONS SPA for the immobilization of antibody is of(simple) operation,and time-saving.It is a good way to immobilize antibody on the gold electric surface of the quartz(crystal).

The statuses and improvements of the laboratory physician clinical teaching / 中华医学教育探索杂志

In this article,we discussed the limitations of present clinical teaching situation, which included curriculum concept, clinical practice condition and quality of teachers. Based on the analysis of present education,we should constitute effective teaching mode,set curriculum system reasonably and take effective teaching means in the clinical teaching of laboratory medicine. It’s very important for educate students with practice talent and high integrative quality.

Analysis of the antibiotic resistance of clinically isolated Pseudomonas aeruginosa strains / 第三军医大学学报

70%). Imipenem was of the strongest activity against Pseudomonas aeruginosa with the susceptibility of 86.3% but cefetaxime and ceftriaxone were of the weakest with the susceptibility of 6.8% and 11.0%, respectively. Conclusion The clinically isolated drug resistant Pseudomonas aeruginosa strains are increasing year by year. Therefore, clinical doctors should choose antibiotics rationally in dealing with the P. aeruginosa infected patients according to drug resistance test.

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.