Development of a Recombinase-aided Amplification Combined With Lateral Flow Dipstick Assay for the Rapid Detection of the African Swine Fever Virus / 生物医学与环境科学（英文）

OBJECTIVE@#To establish a sensitive, simple and rapid detection method for African swine fever virus (ASFV) B646L gene.@*METHODS@#A recombinase-aided amplification-lateral flow dipstick (RAA-LFD) assay was developed in this study. Recombinase-aided amplification (RAA) is used to amplify template DNA, and lateral flow dipstick (LFD) is used to interpret the results after the amplification is completed. The lower limits of detection and specificity of the RAA assay were verified using recombinant plasmid and pathogenic nucleic acid. In addition, 30 clinical samples were tested to evaluate the performance of the RAA assay.@*RESULTS@#The RAA-LFD assay was completed within 15 min at 37 °C, including 10 min for nucleic acid amplification and 5 minutes for LFD reading results. The detection limit of this assay was found to be 200 copies per reaction. And there was no cross-reactivity with other swine viruses.@*CONCLUSION@#A highly sensitive, specific, and simple RAA-LFD method was developed for the rapid detection of the ASFV.

Identification of human cytomegalovirus phosphoprotein 65 in C57BL/6 and BXSB mice as a potential trigger of systemic lupus erythematosus related serum markers

Objective: To investigate the potential role of human cytomegalovirus lower matrix phosphoprotein 65 (HCMV-pp65) in murine systemic lupus erythematosus (SLE). Methods: The prokaryotic plasmid pET-28b-pp65 was constructed to express the HCMVpp65 protein. BXSB mice and C57BL/6 mice were inoculated with pp65 eukaryotic plasmid pcDNA3.0-pp65 intramuscularly 5 times at 2-week intervals, and then the blood of the mice was subsequently collected via the retro-orbital vein. Indirect ELISAs were used to evaluate the concentration of anti-pp65 immunoglobulin G, anti-double-stranded DNA and antinuclear antibodies. Interleukin-1β and tumor necrosis factor-α were also determined by competitive ELISA. At the same time, 3 major SLE-related circulating microRNAs were examined by quantitative RT-PCR. Results: The early production of autoantibodies was observed in pp65-immunized male BXSB as well as C57BL/6 mice. Overexpression of interleukin-1β and tumor necrosis factor-α were detected in pp65-immunized male BXSB mice. Quantitative RT-PCR analyses showed that three SLE related microRNAs (microRNA-126, microRNA-125a, and microRNA-146a) were downregulated in peripheral blood mononuclear cells of pp65-immunized mice. Conclusions: Our findings indicate that HCMV-pp65 immunization strongly triggers the development and progression of SLE-like disease in both BXSB and C57BL/6 mice, which indicates that the immune responses induced by HCMV-pp65 may be involved in the development of SLE.

Study on prescription screening and preparation process of compound danshen pulse capsule / 中国中药杂志

To develop gastric floating erodible plug pulse capsules with compound Danshen as the model drug, in order to realize the pulse release of traditional Chinese medicines. Through the study on impermeable capsules, optimized prescriptions, drug-containing rapid-release tablets and prescription screening, and erodible plug prescription and process, we successfully prepared compounded Danshen pulse capsule, so as to provide a new dosage form for controlling and treating heart disease to better cater to clinical demands.

Changes of the spectrum on thyroid disease after the ten-year implementation of universal salt iodization in Guangxi Zhuang Autonomous Region / 中华流行病学杂志

<p><b>OBJECTIVE</b>To reveal the relationship between iodine nutrition and the change of spectrum on thyroid diseases through comparing the different iodine environments pre- and post- the universal salt iodization(USI)campaign.</p><p><b>METHODS</b>To compare the urinary iodine concentration between 1000 normal people and 5998 patients with thyroid disease who had undergone surgical operations, from 4 major cities, including iodine deficient and rich areas of Guangxi Zhuang Autonomous Region.</p><p><b>RESULTS</b>After USI was put into practice, the urinary iodine concentration of patients with thyroid appeared higher than those of normal people(324.3 µg/L vs. 238.5 µg/L, P < 0.05). The urinary iodine concentrations of nodular goiter,Graves disease, toxic nodular goiter, thyroid papillary carcinoma and Hashimoto's thyroiditis were higher than those before the USI was taken(263.8 µg/L vs. 69.75 µg/L, 289.7 µg/L vs. 228.3 µg/L, 346.8 µg/L vs. 268.4 µg/L, 350.3 µg/L vs. 316.2 µg/L and 378.5 µg/L vs. 305.8 µg/L). The proportions of toxic nodular goiter, thyroid papillary carcinoma and Hashimoto's thyroiditis appeared as 7.59% vs. 4.80%, 5.85% vs. 4.02% and 3.88% vs. 2.46%, all higher than those before the implementation of USI, except the nodular goiter which showed a reduction (63.56% vs. 69.75%).</p><p><b>CONCLUSION</b>The spectrum of thyroid diseases appeared an obvious change in Guangxi within the last 10-year implementation of USI. However, the excessive intake of iodine might serve as a risk factor for toxic nodular goiter, thyroid papillary carcinoma and Hashimoto's thyroiditis.</p>

Down-regulation of fecal miR-143 and miR-145 as potential markers for colorectal cancer

To detect 4 MicroRNA [miRNA] in the stool samples of colorectal cancer [CRC] patients to determine whether these miRNAs could be biomarkers in CRC screening or treatment. A retrospective comparison study was carried out in the Department of Colorectal Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China from September 2009 to March 2011. We detected 4 miRNAs [miR-143, miR-145, miR-21, and miR-106a] in the stool samples of 38 CRC patients and 13 healthy individuals. Total RNA from the stool samples was extracted using the EZNA TM stool RNA kit R6828-01. The miRNA quantification was carried out using TaqMan miRNA assays and the TaqMan Gene Expression Master Mix. The expression levels of miR-143 and miR-145 in the stool of the CRC patients were lower than in those of the healthy persons [p<0.005, median of 2[-Ct]]. No statistically significant difference was found in the expression levels of both miR-21 and miR-106a between the stool of CRC patients and those of the healthy persons [p>0.05]. The detection of fecal miRNAs is a potential method for CRC diagnosis or screening. Particularly, the down-regulation of fecal miR-143 and miR-145 could be a potential marker for CRC

Nosocomial spread of hospital-adapted CC17 vancomycin-resistant Enterococcus faecium in a tertiary-care hospital of Beijing, China / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The incidence of vancomycin-resistant enterococci (VRE) appeared to be increasing in China, but very few nosocomial outbreaks have been reported. Our hospital had experienced an outbreak of VRE since March 2008 to March 2009. The objective of this study was to analyze the molecular features of the isolates and the control measures used to eradicate a VRE outbreak in a tertiary institution in China.</p><p><b>METHODS</b>We characterized VRE isolates from 21 infected and 11 colonized inpatients from a single hospital by pulsed field gel electrophoresis (PFGE), multilocus sequence typing (MLST), the analysis of Tn1546-like elements and virulence genes detection. Infection control measures, including more environmental disinfection, screening for VRE colonization, contact precautions, education and strict antibiotic restriction, were implemented to control the outbreak.</p><p><b>RESULTS</b>During the outbreak, a total of 32 VRE strains were obtained. There were 21 strains found in Emergency Intensive Care Unit (EICU), 9 isolates from Geriatric Ward, and two from other units. All the isolates harbored the vanA gene, however, four of them exhibited the VanB phenotype. Meanwhile, MLST analysis revealed that all isolates belonged to clonal complex (CC) 17. With the infection-control measures, the epidemic was constrained in two units (EICU and Geriatric Ward). After March 2009, no further case infected with VRE was detected in the following one-year period.</p><p><b>CONCLUSION</b>The outbreak was controlled by continuous implementation of the infection control programme, and more rigorous infection control policy is needed.</p>

Sequence analysis of the phosphoprotein gene of peste des petits ruminants virus of Chinese origin / 病毒学报

The nucleotide sequences of P gene from a field strain of peste des petits ruminants virus (PPRV) ("China/Tib/Gej/07-30") was firstly determined. The P gene is 1,655 nucleotides long with two overlapping open reading frames (ORFs). The first ORF is 1530 nucleotides long and would produce P protein of 509 amino acid residues. The second ORF is 534 nucleotides long and would produce C protein of 177 amino acid residues. The first ORF produces a second mRNA transcript of 897 nucleotides long with an extra G nucleotide at position 751. Translation from this mRNA would produce V protein of 298 amino acid residues. The nucleotide and deduced amino acid sequence were compared with the homologous region of other PPRV isolates. At the amino acid level, the "China/Tib/Gej/07-30" shares homology of 86.10%-97.3%, 84.3%-94.9%, and 82.9%-96.3% for P, C, and V proteins respectively. Several sequence motifs in the P genes were identified on the basis of conservation in the PPRVs and the morbilliviruses.

Sequence analysis of the matrix protein and fusion protein genes of a field peste des petits ruminants virus strain from Tibet, China / 病毒学报

The nucleotide sequences of M and F genes from a field strain of peste des petits ruminants virus (PPRV) ("China/Tib/Gej/07-30") was firstly determined. The M gene was 1 483 nucleotides in length with a single open reading frame (ORF), encoding a protein of 335 amino acids. The F gene was 2411 nucleotides in length, encoding a protein of 546 amino acids. The resulting nucleotide sequence and the deduced amino acid sequences were compared with the homologous regions of other PPRV isolates. The nucleotide sequences of M and F genes of the "China/Tib/Gej/07-30" was 92.4%-97.7% and 85.5%-96.1% identical to other PPRV isolates, respectively, while a homology of 97.0%-98.2% and 94.3%-98.2% could be observed at the amino acids level respectively. Several sequence motifs in the M and F genes had been identified on the basis of conservation in the PPRVs and the morbilliviruses. The 3' untranslated region of M gene was 443 nucleotides in length with 82.4%-93.5% identical to other PPRV isolates. The 5' untranslated region of F gene was 634 nucleotides in length with 76.2%-91.7% identical to other PPRV isolates.

Detection of molecular markers of amantadine resistance in avian influenza viruses by pyrosequencing / 病毒学报

Mutation in any of five key amino acid residues (at positions 26, 27, 30, 31 and 34) within the M2 protein of influenza A viruses leads to resistance against the amantodine class of anti-influenza drugs. In this study, a pyrosequencing method was described to rapidly detect established five molecular markers of resistance to M2 blockers, amantadine. The residues L26, V27, A30, S31 and G34 in the M2 protein were targeted for pyrosequencing, and 94 avian influenza viruses were used to perform the amantadine resistance analysis. Our results showed that most of avian influenza viruses were amantadine resistant, Mutations V27I and S31N were founded in these isolates.

External quality assessment on detection of hepatitis C virus RNA in clinical laboratories of China / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>As with many studies carried out in European countries, a quality assurance program has been established by the National Center for Clinical Laboratories in China (NCCL). The results showed that the external quality assessment significantly improves laboratory performance for quantitative evaluation of hepatitis C virus (HCV) RNA.</p><p><b>METHODS</b>Serum panels were delivered twice annually to the clinical laboratories which performed HCV RNA detection in China. Each panel made up of 5 coded samples. All laboratories were requested to carry out the detection within the required time period and report on testing results which contained qualitative and/or quantitative test findings, reagents used and relevant information about apparatus. All the positive samples were calibrated against the first International Standard for HCV RNA in a collaborative study and the range of comparison target value (TG) designated as +/- 0.5 log.</p><p><b>RESULTS</b>The numbers of laboratories reporting on qualitative testing results for the first and second time external quality assessment were 168 and 167 in the year of 2003 and increased to 209 and 233 in 2007; the numbers of laboratories reporting on quantitative testing results were 134 and 147 in 2003 and rose to 340 and 339 in 2007. Deviation between the mean value for quantitative results at home in 2003 and the target value was above 0.5 log, which was comparatively high. By 2007, the target value was close to the national average except for the low concentrated specimens (10(3) IU/ml). The percentage of results within the range of GM +/- 0.5 log(10) varied from 8.2% to 93.5%. Some laboratories had some difficulties in the exact quantification of the lowest (3.00 log IU/ml) as well as of the highest viral levels (6.37 log IU/ml) values, very near to the limits of the dynamic range of the assays.</p><p><b>CONCLUSIONS</b>The comparison of these results with the previous study confirms that a regular participation in external quality assessment (EQA) assures the achievement of a high proficiency level in the diagnosis of HCV infection. During the 5-year external quality assessment, sensitivity and accuracy of detection in most of the clinical laboratories have been evidently improved and the quality of kits has also been substantially improved.</p>

Sequence analysis of the nucleocapsid gene and genome promoter region of peste des petits ruminants virus of Chinese origin / 病毒学报

The N gene and genome promoter nucleotide sequence of a Chinese Peste des petits rumiants virus (PPRV) ("China/Tib/Gej/07-30") was firstly determined. The length of N gene was 1689 nucleotides with a single open reading frame (ORF). The nucleotide and deduced amino acid sequence was compared with the homologous region of other PPRV isolates. The nucleotide sequence of the "China/Tib/Gej/07-30" was 91.7%-97.6% identical to other PPRV isolates, while a homology of 94.9%-98.5% could be observed at the amino acids level. The N gene encoded a protein of 525 amino acids. Several sequence motifs were identified on the basis of conservation in the PPRVs and the morbilliviruses. The genome length of promoter region was 107 nucleotides with 91.8%-98.2% identity to other PPRV isolates. Phylogenetic analysis showed that the "China/Tib/Gej/07-30" belonged to the Asian lineage.

Establishment of the first national standards for nucleic acid amplification technology assay for HBV DNA / 中华肝脏病杂志

<p><b>OBJECTIVES</b>To establish a Chinese national standard for a nucleic acid test (NAT) for HBV DNA.</p><p><b>METHODS</b>The candidate sample of HBV DNA positive plasma was diluted with HBV-negative human plasma. The sample was lyophilised with a concentration of approximately 300,000 copies/ml. The measurement methods used included Roche Amplicor assay (version 2.0) and real-time PCR. The lyophilised preparation was calibrated by the international standard (NIBSC code: 97/746) from NIBSC.</p><p><b>RESULTS</b>The quantity of this lyophilised preparation was (1.29+/-0.24) x 10(5)IU/ml in comparison with the international standard for HBV DNA 97/746. The stability test indicated that the sample was stable at room temperature (20 to 25 degrees C) for 2 weeks and at 37 degrees C for at least 1 week. Long-term stability was observed at 2 to 8 degrees C for 6 months and at -20 degrees C for more than 2 years with no significant changes. The vial-to-vial imprecision rate was 3.53%.</p><p><b>CONCLUSION</b>Based on the results of this study, our lyophilized sample can be used as a standard in China for the nucleic acid test (NAT) for HBV DNA.</p>

Lyophilized standards for the calibration of real time PCR assay for hepatitis C virus RNA / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Since October 1997, an international standard for hepatitis C virus (HCV) nucleic acid amplification technology assay, 96/790, has been available. We compared a series of lyophilized standards with known HCV RNA concentrations against the international standard in fluorescence quantitative PCR detection.</p><p><b>METHODS</b>A series of lyophilized sera were calibrated by ROCHE COBAS AMPLICOR HCV Monitor test against the international standard and sent to various manufacturers to analyse the samples using their own kits. Then calibration curves from the series were compared with that obtained from the external standard calibration curve with the manufacture's series.</p><p><b>RESULTS</b>The standard calibration curve with the series of lyophilized serum showed an excellent correlation (R(2) > 0.98), slope and intercept that were similar to those from the manufacture's series. When the standard calibration curve from the series of lyophilized standards were used to define the values of the given sample, lower coefficients of variation between kits from different manufactures were obtained.</p><p><b>CONCLUSION</b>The results showed that the lyophilized standards could be used to setup the standard calibration curve for clinical HCV RNA quantitative PCR detection.</p>

The study on the treatment of Oviducts Ranae protein with enzyme hydrolysis / 中国中药杂志

The paper introduced a process to enhance the yield of Oviducts Ranae protein using in vitro enzyme hydrolysis. The treatment process included two steps: (1) a 3 - 4 h of hydrolysis of a 0.025 g x g(-1) concentration of substance, at pH 7 and 60 degrees C, using 4% of papain; and (2) followed with a 6 - 8 h hydrolysis, at pH 2 - 2.5 and 60 degrees C, using 3% of pepsin. This treatment process significantly improved the lyophilized Oviducts Ranae in solubility and fluidity, which is convenient for the relative pharmaceutical preparations.

The preparation of arabinogalactan and the mechanism of release / 中国中药杂志

<p><b>OBJECTIVE</b>The study is the research on the preparation of arabinogalactan (AG) dropping pills and the releasing mechanism.</p><p><b>METHOD</b>Use the orthogonal test to find out the best way to produce and advance the preparation of AG dropping pills, analysis according to the chart and DSC to find the releasing mechanism.</p><p><b>RESULT</b>The best preparation conditions are: the liquid of AG is at 75 degrees C, the temperature above the polydimethls iloxane is 30 degrees C, the distance to the frizzed liquid is 6 cm, the speed of the liquid is 30 drop x min(-1). The chart and DSC suggest: The solid disoperation of AG-PREG 4000 the complex is in a certain form which made the melting point decreased obviously, so as to increase the solution of the medicine in carrier to increase the releasing speed.</p><p><b>CONCLUSION</b>The best preparation is reasonable, AG and carrier become a form, the melting point is low, it can release fast.</p>

Selecting methods of controls concentration for internal quality control and continuity of control chart between different reagent lots for HBsAg qualitative detection / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To establish a model for one choosing controls with a suitable concentration for internal quality control (IQC) with qualitative ELISA detection, and a consecutive plotting method on Levey-Jennings control chart when reagent kit lot is changed.</p><p><b>METHODS</b>First, a series of control serum with 0.2, 0.5, 1.0, 2.0 and 5.0ng/ml HBsAg respectively were assessed for within-run and between-run precision according to NCCLs EP5 document. Then, a linear regression equation (y=bx + a) with best correlation coefficient (r > 0.99) was established based on S/CO values of the series of control serum. Finally, one could choose controls with S/CO value calculated from the equation (y = bx + a) minus the product of the S/CO value multiplying three-fold between-run CV to be still more than 1.0 for IQC use. For consecutive plotting on Levey-Jennings control chart when ELISA kit lot was changed, the new lot kits were used to detect the same series of HBsAg control serum as above. Then, a new linear regression equation (y2 = b2x2 + a2) with best correlation coefficient was obtained. The old one (y1 =b1x1 + a1) could be obtained based on the mean values from above precision assessment. The S/CO value of a control serum detected by new lot kit could be changed to that detected by old kit lot based on the factor of y2/y1. Therefore, the plotting on primary Levey-Jennings control chart could be continued.</p><p><b>RESULTS</b>The within-run coefficient of variation CV of the ELISA method for control serum with 0.2, 0.5, 1.0, 2.0 and 5.0ng/ml HBsAg were 11.08%, 9.49%, 9.83%, 9.18% and 7.25%, respectively, and between-run CV were 13.25%, 14.03%, 15.11%, 13.29% and 9.92%. The linear regression equation with best correlation coefficient from a test at random was y = 3.509x + 0.180. The suitable concentration of control serum for IQC could be 0.5ng/ml or 1.0ng/ml. The linear regression equation from the old lot and other two new lots of the ELISA kits were y1 = 3.550(x1) + 0.226, y2 = 3.238(x2) +0.388, and y3 =3.428(x3) + 0.148, respectively. Then, the transferring factors of 0.960 (y2/y1) and 0.908 (y3/y1) were obtained.</p><p><b>CONCLUSION</b>The results shows that the model established for IQC control serum concentration selecting and for consecutive plotting on control chart when the reagent lot is changed is effective and practical.</p>

Construction and expression of RNase-resisting virus-like particles containing PSA mRNA / 中华老年医学杂志

Objective To construct an expression system to produce the virus-like particles containing a part of the sequence of PSA mRNA, which are ribonuclease-resistant due to the encapsulation of the mRNA by bacteriophage MS2 coat proteins. Methods The PCR products of PSA cDNA fragments were cloned to TA vector pBS-T, then the targeted segments could be obtained when the pBS-T-PSA were digested by restriction endonuclease Hind Ⅲ and cloned to prokaryocytic expression vector pNCCL1. The recombinant plasmids named PNCCL1-PSA were transfected into E. Coli BL21-DE3 and induced to express with IPTG. Results The recombinant plasmids were successfully constructed. The bacteriophage MS2 coat protein which expressed in BL21 can self- assemble to form ribonuclease resistant virus-like particles and the PSA mRNA was encapsulated into virus-like particles. Conclusions The virus-like particle containing PSA mRNA can be expressed in prokaryocyte and it can be used as standard and control in detecting PSA mRNA. It provides a new, stable and ribonuclease-resistant RNA standard in RNA detection.