Objective:To establish a method of dual nueleic acid test strips for rapid detection of Bacillus cereus cytK and nhe toxin genes based on polymerase chain reaction(PCR)and colloidal gold technique,and to evaluate its specificity,sensitivity,repeatability and stability.Methods:Bacillus cereus DNA was extracted by boiling method.Specific primers were designed with Bacillus cereus cytK and nhe as the target genes.Clonal transformation was used to identify the PCR products.The optimal labeling amounts of colloidal gold-labeled streptavidin,quality control line(C line),cytK detection line(T1)and nhe detection line(T2)were determined.The nucleic acid test strips were assembled and its specificity,sensitivity,reproducibility and stability were evaluated.Results:The DNA concentration of Bacillus cereus was 248 mg·L-1,and the purities were 1.8-2.0.After cloning and plasmid sequencing,the similarities between the PCR products and the sequences of cytK and nhe registered in the GenBank database were 100％.Under the condition of pH 7.0,the optimal amount of streptavidin labeling per 200 μL of colloidal gold solution was 6.0 μL;the optimal marking amount was 2.00 g·L-1 for the quality control line(C line),0.550 g·L-1 for cytK gene detection line(T1)and 0.2 g·L-1 for nhe gene detection line(T2).In the specificity test,positive result on the test strips was seen only for Bacillus cereus,and no cross-reactivity was observed for Staphylococcus aureus,Escherichia coli,Pseudomonas aeruginosa and Bacillus subtilis,which were consistent with the electrophoresis results.Sensitivity assay showed that even when DNA concentration was reduced to 10-2 mg·L-1,three bands(C line,T1 line and T2 line)could be observed,and the detection limit of the test strip was one-tenth of agarose gel electrophoresis(10-1 mg·L-1).The nucleic acid test strips were verified by different operators in different laboratories,and the results were consistent.The stability of the test strips was verified at the 6th,9th and 12th months,and the results showed good stability.Conclusion:The dual nucleic acid test strip method established in this study can simutaneously detect the cytK and nhe toxin genes of Bacillus cereus with high sensitivity and specificity,achieving short-term visual detection.

Objective:To establish a rapid detection method for pathogenic microorganisms by combining loop-mediated isothermal amplification(LAMP)and clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 12a(Cas12a)(CRISPR-Cas12a)system,and to evaluate its efficacy for detecting the thermolabile hemolysin(tlh)gene of Vibrio parahaemolyticus(Vp).Methods:Using the tlh gene of Vp as the target gene,LAMP primers and CRISPR RNA(crRNA)were designed to construct and optimize the optimal concentration ratio of each component in the LAMP-CRISPR detection system.Bacillus cereus,Staphylococcus aureus,and Escherichia coli were used as control groups,and the specificity,sensitivity,reproducibility and positive conformity rate were verified to establish a rapid LAMP-CRISPR/Cas12a method for detecting the tlh gene of Vp.Results:The method specifically detected Vp,while Bacillus cereus,Staphylococcus aureus,and Escherichia coli yielded negative results.The DNA extraction concentration of Vp was 190.67 mg·L-1 with an A(260)/(A280)ratio of 1.84.Under the reaction conditions of 37℃ with 80 cycles for 40 min using quantitative PCR(qPCR)method,when the concentrations of Cas12a protein and crRNA in the LAMP-CRISPR/Cas12a system were 50 nmol·L-1,the visual brightness and relative fluorescence intensity peaks were high.The sensitivity of LAMP CRISPR/Cas12a for detecting Vp DNA concentration could reach 10-6 mg·L-1.The reproducibility test results showed that different experimenters had consistent results in different experimental environments and times.Conclusion:The established LAMP-CRISPR/Cas12a method can rapidly detect the tlh gene of Vp with high sensitivity and specificity,and can achieve short-term visual detection in the field.

Objective:To establish a method for rapid detection of OXA and par C resistance genes of Acinetobacter baumannii(Ab)by double nucleic acid colloidal gold strip and to develop kit.Methods:DNA of Ab was extracted by heating and boiling method.OXA and par C genes sequences of Ab were selected as target gene fragments based on NCBI.Primers were designed and labeled with 6-FAM,digoxin and biotin,respectively.Drug resistance gene detection reagents were developed,and nucleic acid gold test strips were used for rapid and visual detection.Molecular cloning and sequencing techniques were used to clone positive control samples and evaluate specificity,sensitivity and stability of kit.Results:DNA concentration and purity of Ab extracted by boiling method were good.Homology between cloned and sequenced plasmid DNA and gene sequence in GenBank database was 100%,respectively.Speci-ficity of kit was good,with only Ab showing positive results and other bacterial genera showing negative results;DNA concentration of Ab in double nucleic acid colloidal gold test strip decreased to 10-3 ng/μl,a red line still appeared,whose sensitivity was 10 times higher consistent with minimum detection limit of electrophoresis 10-2 ng/μl;test kits were tested at 3rd,6th and 9th months,and showed good stability.Conclusion:Double resistance detection kit established in this study can simultaneously detect OXA and par C resis-tance of Ab,who has advantages of high sensitivity,strong specificity,rapid and simple,and provides a new method for detection of carbapenem and quinolone antibiotic resistance of Ab.

The aim of this study was to develop a semi-quantitative immunochromatographic method for rapid detection of Newcastle disease virus (NDV) antibodies by expressing HN protein in rice endosperm bioreactor. The recombinant plasmid pUC57-HN was digested by MlyⅠ and XhoⅠ to retrieve the HN gene, while the intermediate vector pMP3 containing promoter, signal peptide and terminator was digested by NaeⅠ and XhoⅠ. The HN gene and the linearized pMP3 were purified and ligated to form a recombinant plasmid pMP3-HN1. Subsequently, pMP3-HN1 and plant vector pCAMBIA1300 were digested by EcoRⅠ and Hind Ⅲ, and the HN1 gene was cloned into pCAMBIA1300. The recombinant plasmid pCAMBIA1300-HN1 was introduced into Agrobacterium tumefaciens EHA105 by electrotransformation, and the pCAMBIA1300-HN1 was transferred into rice callus by agrobacterium-mediated method. After dark culture, callus screening, differentiation, rooting and transplanting, transgenic rice seeds were obtained 4 months later. PCR identified that the HN gene has been inserted into the rice genome. SDS-PAGE and Western blotting indicated that the HN protein was successfully expressed in the positive rice endosperm. The purity of the HN protein was more than 90% by SP cation exchange chromatography and gel filtration chromatography. According to the national standards for the diagnostic techniques of Newcastle disease HI test (HI≥4log₂, positive antibody reaction), a colloidal gold labeled purified HN protein was used to prepare a semi-quantitative test strip by double-antibody sandwich method for rapid detection of NDV antibody. The results showed that the test strip did not cross-react with positive sera against other viruses, and the sensitivity of the test strip reached 1:102 400 for standard positive sera of Newcastle disease. Testing of a total of 308 clinical sera showed that the compliance rate of the test strip with HI test was 97.08%, and the Kappa value was 0.942. In conclusion, high purity recombinant HN protein was obtained from rice endosperm, and a simple, rapid, highly sensitive and highly specific semi-quantitative immunochromatographic strip was developed. The test strip could be used for immune evaluation of the Newcastle disease vaccine.
Animals ; Antibodies, Viral ; Chickens ; HN Protein/metabolism* ; Newcastle Disease/prevention & control* ; Newcastle disease virus/metabolism* ; Oryza/genetics*

Objective To explore the feasibility of biomarkers in static cold storage (SCS) perfusate of donor kidney from donation after cardiac death (DCD) for predicting delayed graft function (DGF) after renal transplantation. Methods Clinical data of 64 recipients and 47 donors undergoing DCD renal transplantation were retrospectively analyzed. All recipients were divided into the DGF group (n=7) and immediate graft function (IGF) group (n=57) according to the incidence of postoperative DGF in the recipients. The levels of neutrophil gelatinase-associated lipocalin (NGAL), liver-type fatty acid-binding protein (L-FABP), interleukin -18(IL-18) and kidney injury molecule-1 (KIM-1) in the SCS perfusate were statistically compared between two groups, and the correlation with DGF was analyzed. The predictive value of each biomarker in the occurrence of DGF in recipients after renal transplantation was analyzed. Results The incidence of DGF in the recipients undergoing DCD renal transplantation was 11% (7/64). The NGAL level in the donor kidney perfusate of the DGF group was significantly higher than that in the IGF group (P=0.009). The NGAL level in the donor kidney perfusate was positively correlated with the incidence of DGF in recipients after renal transplantation (r=0.430, P < 0.001). The receiver operating characteristic (ROC) curve analysis showed that the increased levels of NGAL and KIM-1 in the perfusate yielded certain predictive value for DGF in recipients after renal transplantation (both P < 0.05). The area under the curve (AUC) of combined detection of NGAL and KIM-1 for predicting DGF in recipients after renal transplantation was 0.932 [95% confidence interval (CI) 0.850-1.000]. The sensitivity was calculated as 1.000 and 0.754 for the specificity (P < 0.05). Conclusions The NGAL level in the SCS perfusate of DCD donor kidney is associated with the occurrence of DGF in recipients after renal transplantation. Combined detection of NGAL and KIM-1 levels in the perfusate may accurately predict the occurrence of DGF in recipients after renal transplantation.

Objective:To explore the relationship between new biomarkers in donor blood and delayed graft function after kidney transplantation and evaluate the clinical value of new biomarkers in the diagnosis of DGF (delayed graft function).Methods:For recipients of donor kidney transplantation from August 2016 to December 2017, blood samples were collected from operations of donor organ resection within 12 hours of the day. Enzyme-linked immunosorbent assay (ELISA) was employed for detecting neutrophil gelatinase-associated lipocalin (NGAL), L-type fatty acid binding protein (L-FABP), kidney injury molecule-1 (KIM-1) and interleukin-18(IL-18). They were divided into DGF and EGF (early graft function) groups according to the diagnosis of DGF. The inter-group differences of four new biomarkers were calculated. Receiver operating characteristic curve (ROC curve) was plotted for finding the best positive cutoff value and the sensitivity and specificity of new donor blood marker for diagnosing delayed graft function were calculated.Results:Among them, 8 had postoperative DGF and 62 had none. The overall incidence of DGF was 11.43%. The serum concentration of NGAL was 521.01±132.84 ng/ml in DGF group versus (299.99±100.03) ng/ml in EGF group ( P<0.001). The ROC curve was plotted. With a NGAL concentration >425.15 ng/ml, the sensitivity and specificity for diagnosing DGF were 87.5% and 90.3% respectively. The area under the curve (AUC) was 0.891. The serum concentration of IL-18 was (14.10±12.36) ng/ml in DGF group and (4.61±1.83) ng/ml in EGF group ( P=0.047). With a IL-18 concentration of >5.345 ng/ml, the sensitivity and specificity for diagnosing DGF were 100% and 64.5% respectively. The AUC was 0.914. No significant inter-group difference existed in serum L-FABP/KIM-1. The sensitivity of donor creatinine in the diagnosis of DGF was 62.5%, specificity 75.8% and AUC 0.692. Conclusions:With an excellent level of sensitivity and specificity, an elevated concentration of NGAL/IL-18 in donor blood is superior to traditional creatinine in the diagnosis of DGF after renal transplantation.

Classical swine fever (CSF), one of OIE-listed diseases, is a highly contagious and economically important disease of pigs. Classical swine fever virus (CSFV) is the causative agent of CSF. The capsid (C) protein and the glycoproteins Erns, E1 and E2, are structural components of the virus. E2 is the most immunogenic protein of the CSFV glycoproteins, inducing neutralizing antibodies that provide protection against lethal CSFV challenge. In a previous study, we developed a murine MAb HQ06 against the E2 protein of CSFV. In this study, the variable region genes from HQ06 and constant regions gene of swine antibody are fused and cloned into the eukaryotic expression vectors to establish a cell line which can stably express a chimeric porcinized MAb (cHQ06) against E2 in CHO cell. The purified cHQ06 antibody protein was determined to be successfully generated, which exhibited high reactivity between cHQ06 and the E2 protein of CSFV by enzyme-linked immunosorbent assay (ELISA) and Western blotting. More importantly, we investigated the neutralizing activity of cHQ06 against CSFV. In conclusion, this study generated cHQ06 for efficient and stable production which can be used against to develop novel diagnostic assays, investigate the structure and function of the E2 protein and generate novel preparations of diagnosis and treatment.

Objective To summarize the clinical experience of the application of bortezomib desensitization regime prior to secondary renal transplantation in a highly-sensitized recipient. Methods At 13, 10 and 6 d prior to secondary renal transplantation, one patient positive for donor specific antibody (DSA) was subcutaneously administered with bortezomib at a dose of 1.3 mg/m2 combined with a low dose of immunoglobulin. Postoperatively, immunosuppressive regime of tacrolimus (FK506), mycophenolat sodium and methylprednisolone was adopted. The serum creatinine (Scr), blood urea nitrogen (BUN) levels, FK506 concentration, DSA titre, C3d binding DSA (C3d-DSA) titre, pathological biopsy of the renal graft and adverse reactions were observed. Results During 12-month follow-up after administration of bortezomib, the Scr level was declined and maintained at 130 μmol/L, and the BUN level was remained at 3.9 mmol/L. The DSA level was significantly decreased and the C3d-DSA was negative. At postoperative 4 and 9 months, pathological biopsy of the renal graft revealed that the patient was positive for C4d, prompting the chronic active antibody mediated rejection (AMR). The patient presented with grade Ⅲ peripheral neuropathy. Conclusions Application of preoperative bortezomib desensitization regime can effectively down-regulate the DSA level in the recipient and avert the incidence of acute rejection in highly-sensitized patients undergoing secondary renal transplantation. Comprehensive treatment using bortezomib is recommended for preoperative desensitization in the highly-sensitized transplant recipients.

Objective Based on the Traditional Chinese Medicine Inheritance Support System (TCMISS) (V2.0), to analyze the point-selection rules in acupuncture-moxibustion prescriptions for gastroptosis indexed by China National Knowledge Infrastructure (CNKI), Wanfang and Vip databases, and to obtain novel prescriptions, for providing clinical references. Method Acupuncture-moxibustion prescriptions for gastroptosis indexed by CNKI, Wanfang and Vip databases were collected and filtered, and then input into the TCMISS. The prescriptions were analyzed by using data mining method. Result The frequency and core combination of the commonly-used acupoints were determined out of the 76 eligible prescriptions for gastroptosis, and 3 novel prescriptions were obtained. Conclusion The TCMISS is an important tool in mining and analyzing the point-selection rules in acupuncture-moxibustion treatment, and the new acupoint prescriptions generated by this system provide references to the treatment of gastroptosis.

OBJECTIVETo assess the association between single nucleotide polymorphisms (SNPs) of calcium channel β 2 subunit (CACNB2) gene and essential hypertension (EH) in ethnic Han Chinese in Wenzhou area, and to study the influence of rs7069292 alleles on gene expression with luciferase reporter technique.

METHODSSixty hundred and thirty seven Han Chinese with EH and 600 normal controls were enrolled. Genotypes of 6 SNP within CACNB2 gene including rs2228645, rs2357928, rs7069292, rs7099380, rs10764319 and rs11014166 were determined with matrix assisted laser desorption ionization/time of flight mass spectrometer (MALDI-TOF MS). A luciferase reporter gene plasmid containing the fragment flanking rs7069292 (-2831 bp to -2460 bp) in the 5' regulatory region of CACNB2 was constructed.

RESULTSCompared with the control, CT and TT genotypes for the rs7069292 locus were significantly more common in EH group (5.20% vs. 2.17%, 2.59% vs. 1.08%, P< 0.05). CC genotype was not found. Promoter activity for allele C of the rs7069292 locus was significantly increased compared with allele T (P< 0.05). No significant difference was detected for other 5 SNPs in terms of genotypes and allele frequency.

CONCLUSIONThe rs7069292 CT polymorphism of the CACNB2 gene is associated with EH in ethnic Han Chinese from Wenzhou area. A T>C mutation may affect the expression of CACNB2.

Aged ; Alleles ; Base Sequence ; Calcium Channels, L-Type ; genetics ; Case-Control Studies ; Cell Line ; Female ; Gene Frequency ; Genetic Predisposition to Disease ; Genotype ; Humans ; Hypertension ; genetics ; Male ; Middle Aged ; Polymorphism, Single Nucleotide