Principle of recombinase polymerase amplification and its application progress in medical laboratory science / 中华检验医学杂志

Recombinase polymerase amplification (RPA) is a novel technology for nucleic acid isothermal amplification. It can achieve the rapid amplification and detection of a target gene under 37-42 ℃. This amplification method is highly sensitive, more specific and less instrument-dependent than other existing methods, and it can also integrate multiple detection modes. Therefore, it is especially suitable for applying in low-resource settings and conducting point-of-care tests. Starting from the reaction principles and the experimental design of RPA, this article pointed out some key points when using RPA in a clinical setting. The current development and related problems of RPA were concluded and the various future uses of this method were also prospected.

Effect of urinary albumin/creatinine ratio on type 2 diabetic retinopathy and its cut-off value for early diabetic retinopathy diagnosis / 中华内分泌代谢杂志

Objective:To evaluate the effect of urinary albumin creatinine ratio (UACR) on diabetic retinopathy (DR) in patients with type 2 diabetes. Receiver operating characteristic (ROC) curve was applied to find the cut-off value of UACR for diagnosing DR.Methods:A prospective cohort study of 2 490 patients with type 2 diabetes was conducted with a mean follow-up of 7 years ranging from 3 to 10 years. Dilated fundus examination was performed once a year, and patient history and clinical data were collected and analyzed. Patients were divided into three groups according to the UACR: Q1, normal urinary albumin group (UACR<30 mg/g), Q2, microalbuminuria group (30 mg/g≤UACR≤299 mg/g), and Q3, macroalbuminuria group (UACR>300 mg/g), respectively. Cox regression analysis was used to explore the influence of UACR and other factors on DR, and ROC curve was drawn to evaluate the value of UACR in diagnosis of DR.Results:Cox regression analysis showed that UACR was the risk factor of DR( HR=1.108, 95% CI 1.023-1.241, P<0.001). It showed that the patients in Q3 group had the highest risk of proliferative DR ( HR=3.128, 95% CI 2.025-4.831, P<0.001), the patients in Q2 group followed( HR=1.918, 95% CI 1.355-2.714, P<0.001), and the patients in Q1 group were the lowest. ROC curve analysis showed that area under UACR curve was 0.746(95% CI 0.681-0.812, P<0.001), and the cut-off value, sensitivity, and specificity for the diagnosis of PDR were 54.12mg/g, 0.769, and 0.653, respectively. Conclusion:The UACR can predict the progression of PDR in type 2 diabetes patients, therefore it may be used as a preliminary predictor for the progression of DR.

Effectiveness evaluation of the Thyroid Imaging Report and Data System proposed by American Radiological Society (2017) (ACR-TIRADS) for differential diagnosis in thyroid nodules / 中华超声影像学杂志

Objective@#To evaluate the effect of the Thyroid Imaging Report and Data System proposed by American Radiological Society (ACR-TIRADS) for differential diagnosis in thyroid nodules, and compare ACR-TIRADS to the TIRADS proposed by Kwak et al.(K-TIRADS) and the ultrasound-based risk stratification system evaluated by American Thyroid Association (ATA-Risk Stratification).@*Methods@#The clinical data of 1 760 patients with 1 912 thyroid nodules from 8 hospitals in Jiangsu province were retrospectively analysed. All of them were categorized based on ultrasound-based risk stratification systems. The ROC curve was established to assess and compare the diagnostic value of the systems.@*Results@#The area under the ROC curve (AUC) of ACR-TIRADS was 0.830, with high sensitivity and negative predictive value (86.9% and 87.5%, respectively), and relatively low specificity and positive predictive value (64.1% and 62.9%, respectively). The sensitivity and specificity of K-TIRADS were up to 84.9% and 76.1%, respectively. The AUC of ATA-Risk Stratification was 0.852, with relatively high specificity (83.4%), and low sensitivity (79.4%). There were significant differences in the AUC among the three ultrasound-based risk stratification systems, of which K-TIRADS was the highest (P<0.001). There was no significant difference in sensitivity of ACR-TIRADS and K-TIRADS (P=0.137), but significantly higher than that of ATA-Risk Stratification (P<0.001). There were significant differences in the specificity among the three systems, of which ATA-Risk Stratification was the highest (P<0.001). In addition, there were 109 nodules (5.7%) couldn′t be classified based on ATA-Risk Stratification, with high malignancy rate of 31.2%.@*Conclusions@#The diagnostic efficiency of ACR-TIRADS is good, but lower than K-TIRADS and ATA-Risk Stratification. ACR-TIRADS has the highest sensitivity, and ATA-Risk Stratification has the highest specificity, while the overall diagnostic efficiency of K-TIRADS is the best.

Distribution and analysis of clinical multi-drug resistant bacteria in a comprehensive hospital / 国际检验医学杂志

Objective To understand the distribution characteristics of clinical multi-drug resistant bacteri-a,provide a scientific evidence for control of infection and rational use of antibiotics.Methods The distribu-tion of multi-drug resistant bacteria in the hospital for three years was analyzed retrospectively.Results There were 19 354 non-repeating strains from 2014 to 2016,and 21.9%(4 234)of the total strains were multi-ple resistant strains.Among them,ESBLs-producing Escherichia coli was the most,followed by carbapene-re-sistant Acinetobacter baumannii(MDR-AB),ESBLs-producing Klebsiella pneumoniae,multidrug-resistant Pseudomonas aeruginosa(MDR-AB),Production of carbapene-enzyme Enterobacteriaceae bacteria(CRE), vancomycin-resistant enterococci(VRE),concentrate mainly on the ICU for high-risk areas of infection.The most were from the respiratory system specimens,followed by the urinary system specimens.Conclusion Multiple resistant bacteria are growing critical.There should be more attention to be paid in bacteriological ex-amination for clinic,the clinical isolation of pathogenic microorganisms in the hospital should be grasped.The antimicrobial agents should be rationally applied according to the results of bacterial susceptibility,in addition the management of antimicrobial agents and multi-drug monitoring should be strengthened.

Distribution characteristics of microorganisms on the skin of submariners during closed environment voyages / 军事医学

Objective To investigate the distribution and changes of microorganisms on the skin of submariners under a chronically closed environment , and provide reference for targeted medical support .Methods One hundred and twenty-two samples were collected using swab.After culture and isolation, the microbes were identified by matrix-assisted laser desorption/ionization time of flight mass spectrometry ( MALDI-TOF-MS) .Results A total of 52 types of 229 bacteria and 2 types of fungi were isolated . Major opportunistic pathogens included Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter cloacae, while major dwelling bacteria included Micrococcus luteus, Oslo Mora bacteria, Acinetobacter, Staphylococcus epidermidis, and Serratia marcescens.Compared with the early period of the task, major opportunistic pathogens and dwelling bacteria were significantly increased in the middle and late period of the task .Conclusion The skin microbes of the submariners are investigated , targeted drugs need to be prepared for daily medical support and war trauma .

Comparative analysis of pathogenic bacteria distribution and drug resistance from NICU blood culture at different altitudes / 重庆医学

Objective To compare and analyze the influencing factors of the distribution and drug resistance of blood culture positive pathogens in neonatal intensive care unit (NICU) at different altitude areas.Methods The distribution of blood culture positive pathogens and clinical susceptibility of children in NICU of two different altitude hospitals in 2015 were retrospectively analyzed.Results In 2015,children in NICU in upper elevation district hospital mainly infected with 19 strains(18.4％) of epidermis staphylococcus,18 strains(17.5 ％) of Escherichia coli,14 strains(13.6 ％) of Klebsiella pneumoniae,14 strains(13.6 ％) of Hemolysis staphylococcus,12 strains(11.7 ％) of Stenotrophomonas maltophilia;Children in NICU at low altitude hospital mainly infected with 31 strains(19.7％) of epidermis staphylococcus,27 strains(17.2％) of Achromobacter xylosoxidans,18 strains(11.5％) of Hemolysis staphylococcus,14 strains(8.9 ％) of Klebsiella pneumoniae,14 strains (8.9 ％) of Acinetobacter baumannii.The detection rate of Gram-negative bacilli in high altitude hospital was higher,and the detection rate of Gram positive cocci in low altitude hospital was higher.In high-altitude district hospital,the detection rate of methicillin-resistant coagulase negative staphylococci (MRCNS) extended-spectrum β-lactamase (ESBLs),and multidrug-resistant Acinetobacter baumannii(MDRAB) were than low altitude hospital.Conclusion Escherichia coli and Stenotrophomonas maltophilia detection rate and common antibiotics sensitive rate are relatively high at upper elevation areas;Detection rate of coagulase negative Staphylococcus aureus and common antibiotics resistance rate are high in low altitude.Different altitudes environmental factors may play an important role in pathogens distribution and drug resistance from NICU blood culture.

Study on the relationship between insulin growth factor-1 and liver fibrosis in patients with chronic hepatitis C with type 2 diabetes mellitus / 中国医师杂志

Objective To investigate the correlation between serum level of insulin growth factor 1 (IGF-1) and the degree of liver fibrosis in patients with chronic hepatitis C (CHC) complicated to type 2 diabetes mellitus (T2DM). Methods The cases were divided into CHC with T2DM (39 cases), CHC (96 cases), T2DM (60 cases), and healthy control (60 cases) groups. Their human data were collected and the fasting blood glucose, insulin and insulin-like growth factor-1 levels were detected, and the insulin resistance index ( HOMA-IR) wwer calculated. The serum levels of alanine transaminase ( ALT) , aspartate transaminase ( AST) , hepatitis C virus ( HCV) RNA load and HCV genotypes were detected simultaneously in patients with hepatitis C, and liver stiffness were measured ( LSM) by transient elastography ( TE) and aspartate aminotransferase-to-platelet ratio index ( APRI) score was performed. Results ⑴ There was no significant difference between CHC with T2DM group and CHC group in diabetes family history(P>0. 05), but two groups were significantly lower than that of T2DM group (P<0. 05). ⑵The levels of fasting insu-lin (FI) and HOMA-IR in CHC with T2DM group and T2DM group were significantly higher than those in the other two groups (P<0. 05), while the levels of IGF-1 in two groups were significantly lower than those in the CHC group, and were more lower than the control group (P<0. 05). ⑶Compared the serum ALT, AST and HCV RNA load between CHC with T2DM group and CHC group, there had no significant differ-ence (P>0. 05);however, the proportion of 1b genotype, LSM and APRI score of CHC with T2DM group were significantly higher than those in CHC group(P<0. 05). ⑷ The level of serum IGF-1 was negatively correlated with HOMA-IR, LSM and APRI in CHC with T2DM group (r= -0. 71, -0. 75, -0. 69, P<0. 01). Conclusions The degree of hepatic fibrosis and the damage of IGF-1 synthesis in CHC patients with T2DM were significantly higher than those in non T2DM patients, which might be related to the insulin resistance caused by 1b genotype HCV infection.

Establishment and application of the molecular-beacon-based asymmetric recombinase amplification for detecting Staphylococcus aureus / 中华检验医学杂志

Objective To establish a homothermal and fast detecting method on pathogenic bacteria by combining recombinase-aid amplification (RAA) with molecular beacon.Methods The establishment of the methodology.Staphylococcus aureus specific primers were designed from the relative region of the staphylococcal protein A (SPA).Asymmetry amplification was optimized by adjusting the primer concentration ratios.The results of amplification and hybridization were visualized and analyzed by agarose gel electrophoresis and fluorescence detection.The sensitivity was identified by detecting dilute positive plasmids.And the specificity was determined using RAA method by detecting 72 pathogenic bacteria,including Staphylococcus aureus and other Staphylococcus spp.from the Department of Clinical Laboratory of Daping Hospital in December 2016.Besides,the Kappa analysis and the clinical diagnosis efficiency were investigated by analyzing 39 extra strains in the laboratory in December 2016.Results When the concentration ratio of restrictive and non-restrictive primer was 1:20,the yield efficiency of single-stranded DNA (ssDNA) reached the peak.And as for the hybridization efficiency,the asymmetry amplification was higher than symmetry amplification.Twenty copies/μl was proposed as the limits of detection by testing dilute plasmids.And the RAA hybridization method could distinguish Staphylococcus aureus with other Staphylococcus spp.Comparing with traditional detection methods with a Kappa index of 0.860,this method shows a good consistency.By analyzing the 111 bacteria,the sensitivity of the method is 92.5％ (37/40),the specificity is 97.2％ (69/71),the positive predictive value is 94.9％ (37/39),the negative predictive value is 95.8％ (69/72),the positive likelihood radio is 33.04,the negative likelihood radio is 0.077,the Youden index is 0.897 and the Kappa index is 0.902.Conclusion Through the combination of asymmetry recombinase-aid amplification optimization and molecular beacon probe,a new method of detecting bacteria DNA with RAA hybridization technique is established,providing the foundation for its clinical application.

Isolation and change of drug resistance of mucoid Pseudomonas aeruginosa in sputum from 2013 to 2015 in a hospital / 国际检验医学杂志

Objective To understand the isolation and change of drug resistance of mucoid Pseudomonas aeruginosa in sputum from 2013 to 2015 so as to provide a scientific basis for reasonable clinical use of antibacterial drugs.Methods The isolation,culture and identification were carried out according to the fourth edition of National Clinical Laboratory Operation Rules.The drug susceptibility testing was performed with the use of Kindy-Bauer.The drug susceptibility testing results were judged according to the standards of CLSI 2014.The clinical data were analyzed by software WHONET 5.6.Results Among 1 653 strains of Pseudomonas aeruginosa isolated in the clinical sputum specimens from 2013 to 2015,including 255(15.4%)strains of mucoid Pseudomonas aeruginosa;during the three years,the drugs of highest drug resistance rate was piperacillin,which was 29.0%;the drug resistance rate less than 10.0% had amikacin and piperacillin/tazobactam;the drugs with larger increase range of resistance rate included imipenem,levofloxacin,ciprofloxacin and ciprofloxacin,their resistance rates were increased from 12.5%,9.7%,8.3% and 9.7% in 2013 to 20.5%,17.0%,19.3% and 15.9% in 2015.Conclusion The isolating rate of mucoid Pseudomonas aeruginosa in sputm is gradually increased year by year from 2013 to 2015.At the same time,the drug resistance rates show an increasing trend in recent three years.It is necessary to strengthen the surveillance of drug resistance of mucoid Pseudomonas aeruginosa.

Comparison of diagnostic value between TIRADS and ultrasound patterns of ATA (2015) guidelines in the differentiation of benign and malignant thyroid nodule / 中华内分泌代谢杂志

To compare the diagnostic value between the thyroid imaging reporting and data system ( TIRADS) and ultrasound ( US ) patterns of 2015 American Thyroid Association ( ATA ) guidelines in the differentiation of benign and malignant thyroid nodules. 639 patients in Jiangsu province who were scheduled for ultrasound-guided fine-needle aspiration biopsy or thyroidectomy were recruited for the retrospective study. All of them were categorized based on TIRADS and ultrasound patterns of ATA ( 2015 ) guidelines. The receiver operating characteristic curve was established to assess and compare the diagnostic value of the two models. Results:( 1 ) 639 patients with 847 thyroid nodules were included in this study, 510 females and 129 males. The mean age was (46. 77 ±12.98)yearsold. (2)818nodulescouldbeclassifiedaccordingtoTIRADS. ThemalignancyratesofTIRADS2,3, 4A, 4B, 5 were 0, 15. 9%, 49. 1%, 78. 8% ,and 100%, respectively. (3) Ultrasound patterns of ATA could be assigned to 793 nodules. The malignancy rates of nodules with very low, low, intermediate, high suspicion for malignancy were 6. 2%, 10. 3%, 24. 9% and 70. 1%, respectively. (4) Ultrasound patterns of ATA had higher specificity (77. 9%) compared to TIRADS. The sensitivity and area under curve of ultrasound patterns of ATA were lower than those of TIRADS, though, not significant. Ultrasound patterns of ATA(2015) guidelines may yield higher specificity in the differential diagnosis of benign and malignant thyroid nodules, while TIRADS classification may offer a relatively higher sensitivity and area under curve.

Expression of Th17 cells and related cytokines in peripheral blood of patients with Graves′disease / 中国免疫学杂志

Objective:To explore the proportions of Th17 cells in the peripheral blood and levels of IL-17,IL-23 in the serum of patients with Graves′disease ( GD ) and their clinical significance.Methods: We studied 29 patients with GD ( GD group ) , and reevaluated the GD group after therapy ( euthyroid GD group ).29 gender-and age-matched volunteers were selected as the normal control ( NC group).The proportions of Th17 cells were investigated by flow cytometry.The levels of IL-23,IL-17 in the serums were measured by ELISA.The levels of FT3,FT4,TSH were determined by ECLIA and the levels of TrAb were tested by RRA.Results:There were no significant difference among 3 study groups in sex and age match ( F=0.0075 , P>0.05;χ2=0.4213 , P>0.05 ).The proportions of Th17 cells and the levels of IL-17 , IL-23 were increased in the GD and euthyroid GD patients compared with the control group (respectively,P0.05).Correlation analysis revealed that the proportions of Th17 cells ,and the levels of IL-17,IL-23 were positively correlated with the levels of FT3,FT4,TrAb(r=0.588 2,0.337 2,0.371 0;0.549 6,0.287 5,0.342 7;0.361 0,0.420 8, 0.330 8;P<0.05 ,for all parameters ) ,and were negatively correlated with the levels of TSH ( r=-0.319 7 ,-0.472 8 ,-0.428 2;P<0.05,for all parameters).Conclusion:Th17 cells and their related cytokines IL-17,IL-23 are highly expressed in the serum of patients with GD.Th17 cells and their relative cytokines have certain relevance with 4 thyroid function parameters of the patients with GD , which can be used as biological markers for GD.

Genotyping of Acinetobacter calcoaceticus-Acinetobacter baumannii complex and analysis of antibiotics resistance / 国际检验医学杂志

Objective To identify strains of Acinetobacter(A.)calcoaceticus-A.baumannii complex accurately,and investigate the species distribution of Acinetobacter calcoaceticus-A.baurnannii(ACB)complex isolated in Daping Hospital.Analysis the anti-biotics resistance of ACB complex.Methods A total of 95 clinica1 isolates of ACB complex were collected from Daping Hospital from February to April 2014,identify by sequence analysis of 1 6S rRNA gene spacer region.Use VITEK-2compact automatic iden-tification of bacteria by susceptibility meter to detect the precise identification of all ACB complex group of drug sensitivity.Results Among all the 95 strains of ACB complex identification results were A.baumanni (81,85.26%),A.pittii(10,10.53%),A.noso-comialis (4,4.21%).A.baumannii to third generation cephalosporins,aminoglycosides and carbapenem antibiotic resistance in seri-ous condition,the sensitive rate was only about 20.00%.But A.pittii and A.nosocomialis had a high sensitivity rate to commonly used antibiotics.Conclusion VITEK-2 Compact automatic identification of bacteria susceptibility meter has limitations in identifica-tion of Acinetobacter,with analysis of 1 6S rRNA gene sequencing,the ACB complex could be accurately identified.There is signifi-cant difference in the composite group-resistant characteristics of each species,clinical infection is also various.

Study on levels of IFN-γ,IL-6,IL-17 and TGF-β1 in patients with Graves′disease / 中国免疫学杂志

Objective:To explore the role of cytokines in the pathogenesis of Graves′disease(GD),by detecting the levels of IFN-γ,IL-6,IL-17 and TGF-β1 in GD patients who were newly diagnosed.Methods:A total of 23 patients with new onset GD and 23 gender-and age-matched healthy controls were examined.The levels of serum IFN-γ, IL-6, IL-17 and TGF-β1 were measured by ELISA,FT3,FT4 and TSH levels were determined by ECL IA;TrAb levels were tested by RRA.Results: There were no significant difference among GD and NC group in sex and age match ( t=0.334 8 ,P>0.05;χ2=0.410 7 ,P>0.05 ).The levels of serum IFN-γ,IL-6,IL-17 and TGF-β1 in the GD group were significantly higher than the control group ( P<0.05 ) .Correlation analysis revealed that IFN-γ,IL-6,IL-17 and TGF-β1 were positively correlated with FT3,FT4(r=0.324 6,0.453 2,0.431 0,0.463 8;0.413 2,0.441 5, 0.436 2,0.467 1;P<0.05 ).Conclusion: IFN-γ, IL-6, IL-17 and TGF-β1 are highly expressed in the newly diagnosed GD patients.They play an important role in the pathogenesis of GD ,and provide helpful evaluation indices of immune dysfunction to Graves disease.

Detection and drug susceptibility of Ureaplasma urealyticum and Mycoplasma hominis in 8 546 cases of genitourinary tract specimen / 国际检验医学杂志

Objective To investigate the mycoplasma separation rate in the patient with genitourinary tract inflammation in our hospital and the in vitro sensitivity to 12 kinds of antibacterial drugs for guiding clinical rational drug use.Methods 8 546 cases of genitourinary tract specimen were collected from our hospital STD clinical department and performed the culture and the in vitro drug susceptibility test by adopting the mycoplasma culture,identification and drug susceptibility integration reagent kit.Results Among 8 546 cases of patient specimen,3237 cases were mycoplasma positive,in which 2 897 cases (89.5%)were simple Ureaplas-ma urealyticum(Uu)positive,39 cases (1.2%)were simple Mycoplasma hominis (Mh)positive and 301 cases (9.3%)were Uu and Mh positive,there was statistically significant difference between any two groups (P <0.01 );the drug susceptibility test showed that the top 3 of sensitivity rates to antibacterial drugs in 2 897 cases of Uu infection from high to low were josamycin (98.4%),doxycline (97.9%)and minomycin (97.6%),the top 3 of drug resistance rates from high to low were ciprofloxacin (71.8%),spiramycin (46.8%)and ofloxacin (35.6%).The top 3 of sensitivity rates to antibacterial drugs in 39 cases of Mh infec-tion from high to low were josamycin (96.7%),doxycline (91.2%)and minomycin(90.8%),and the top 3 of drug resistance rates were ofloxacin (68.9%),ciprofloxacin (67.8%)and roxithromycin (54.2%).The top 3 of sensitivity rates to antibacterial drugs in 301cases of Uu and Mh infection from high to low were doxycline (95.2%),minomycin (94.8%)and josamycin (92.1%),and the top 3 of drug resistance rates from high to low were ciprofloxacin (83.3%),ofloxacin (80.1%)and levofloxacin (76.3%).Conclu-sion Uu and Mh are the common pathogens of genitourinary tract infection.Mycoplasma isolated from genitourinary tract speci-mens in our hopsital is dominated by Uu,so the drugs with higher sensitivity such as josamycin,doxycycline and minocycline should be used as the first choice in the treatment of mycoplasma infection.

In vitro antibacterial activity of tigecycline against carbapenems-resistant Acinetobacter calcoacetcus-Acinetobacter baumannii complex / 国际检验医学杂志

Objective To measure the in vitro antibacterial activity of tigecycline against carbapenems-resistant Acinetobacter calcoacetcus-Acinetobacter baumannii complex.Methods The isolated strains of carbapenems-resistant Acinetobacter calcoacetcus-Acinetobacter baumannii complex were collected in our hospital from December 2013 to February 2014.The MIC test strip was a-dopted to measure the MIC value of tigecycline.The break point adopted the judgment criteria published by FDA.Results All 61 strains of carbapenems-resistant Acinetobacter calcoacetcus-Acinetobacter baumannii complex had extremely high drug resistant rate to the commonly used antimicrobial agents.The sensitive rate of tigecycline was 80.3%,intermediation was 19.7% and no re-sistant strain was found in this study.MIC50 and MIC90 were 2 μg/mL and 3 μg/mL respectively.Conclusion Tigecycline has bet-ter in vitro antibacterial activity to the carbapenems-resistant Acinetobacter calcoacetcus-Acinetobacter baumannii complex isolated in our hospital.

Establishment of chip technology-based real-time PCR platform and its application in rapid detection of HCV and HIV-1 / 国际检验医学杂志

Objective To establish the chip technology‐based real‐time PCR (RT‐PCR) platform and to apply it in the viral loads detection of HIV‐1 and HCV .Methods Based on the primers designed to aim at the conversed regions of HIV‐1 and HCV , The gene chip tube was prepared ,and the RT‐PCR reaction system was established for the simultaneous determination of viral loads .And the melting curves were used to distinguish viral species .The sensitivity and specificity of the method were estimated , and performance of the method was verified by using clinical samples .Results The specificity of the method was good .The lowest detectable limit of the detection method of HCV and HIV‐1 was 1 × 103 copy/mL .The clinical samples with viral loads around 1 × 103 -1 × 106 copy/mL could be detected accurately .Conclusion The method provides a new idea for the detection of HCV and HIV‐1 .

Molecular inversion probe-based single base mutations of hepatitis B virus resistance gene analysis / 中华检验医学杂志

Objective To establish a molecular inversion probe ( MIP) method for detection of single base drug-resistance mutation in Hepatitis B virus ( HBV) gene.Methods The HBV wild type and YVDD mutant strain were isolated by Daping Hospital of the Third Military Medical University.The MIP was designed and applied to detect the HBV drug-resistance YVDD mutation in one case of wild type and one case of YVDD mutant HBV strain isolated previously.The results of MIP method were compared with that of sequencing to evaluate the detection accuracy.Results Thermal cycling single-base extension and connection reaction performed by Taq DNA Ligase and Ampligase DNA Ligase could ensure the specificity of the detection.The optimum probe concentration of MIP was 1 nmol/L.Through detection of the target gene with different DNA concentrations , the detection sensitivity of MIP was determined as 1 nmol/L.The results of MIP were consistent with that of sequencing method in detection of the clinical samples.Conclusion MIP is successfully used to detect single-base drug-resistance mutation in HBV gene.

The etiology analysis of 92 cases of undersized children in the area of Huai'an city of Jiangsu province / 国际中医中药杂志

Objective To investigate and analyze the dwarf reasons for children in the area of Huai'an city,Jiangsu province.Methods A retrospective analysis of 92 cases of children with short stature in our hospital in recent 5 years had been made.Results The dwarf reasons for the 92 cases of undersized children were:lack of growth hormone (53.3％),physical sexual puberty delay (16.3％),hypothyroidism (9.8％),turner syndrome (7.6％),nanosoma essentialis (5.4％),familial short stature (4.3％),intrauterine growth retardation (2.2％)and glycogen storage disease type Ⅰ (1.1％).Conclusion The main dwarf reasons for children were growth hormone deficiency and physical sexual puberty delay,and medical treatment should be used as soon as possible.

Study on morphology of surface atoms conformation of nanogold-based genechip / 生物医学工程学杂志

Conformations of surface atoms in various stages of nanogold-based genechip testing were scanned by the atomic force microscope based on the scanning tunneling microscope. The findings were: First, the surface atoms of genechip slide (formylphenyl glass) were in a regular porous-arrangement; Second, after combination with probe, the regular porous arrangement changed to be irregular; Third, after hybridization with the target nucleic acid, the surface atoms were once again in a cable-like arrangement which was relatively structured and intensively cross-parallel. However, after the silver staining, the surface atoms showed a larger block structure with serious unevenness. From these results we can intuitively know the process and differences in probe combination, nucleic acid hybridization, and silver staining. Moreover, the relevant experiment was verified at the micro-level.

A study on surface plasmon resonance-based gene chip / 生物医学工程学杂志

The surface plasmon resonance (SPR)-based gene chip was prepared according to the following processes: First, a film of nanogold, which was synthesized by using Frens' method, was plated on chip by Chlorauric acid/hydroxylamine method. Then probes were fixed on nanogold film by Self-assembled monolayer (SAM) technology. Subsequently, the fixing time and concentration of probes, the sensitivity and the specificity of the chip were optimized. Our results suggested that the chip plated with 2.5 nm nanogold film has a better SPR reflection, and when fixed by probes for 4.5 h at the concentration of 1 500 nmol/L, the gene chip also shows a fine performance of detection and can identify accurately the mismatch between bases in SPR detection system. The gene chip constructed in the research can be used for SPR sensor detection.