Real-time Fluorescence Quantitative PCR Assay Research Articles

RPS3-induced antiviral cytokines inhibit the proliferation of classical swine fever virus.

Classical swine fever virus (CSFV) infection results in serious economic losses to the pig industry. This positive-sense RNA virus hijacks cell host proteins for its own replication. Although previous studies have shown that RPS3, a40S ribosomal subunit protein, is mainly required for DNA repair, apoptosis and inflammation, the effect of RPS3 on CSFV replication remains uncertain. Thus, we investigated the potential role of RPS3 in CSFV infection in RPS3-knockdown and -overexpressing cell lines using real-time fluorescence quantitative PCR (RT-qPCR) and indirect immunofluorescence assays. Results showed that knockdown of RPS3 by lentiviruses enhanced CSFV replication, whereas overexpression of RPS3 by lentiviruses inhibited CSFV replication. These findings indicated the antiviral role of RPS3 in CSFV infection. Subsequent experiments revealed that CSFV replication was inhibited in cells cultured with the supernatants of RPS3-overexpressing cell, suggesting that the RPS3-mediated inflammatory response was involved in CSFV infection. Furthermore, enzyme-linked immunosorbent assay (ELISA) revealed that the secretion of antiviral cytokines (IL-8 and INF-β) was increased in cells with sufficient RPS3 expression but decreased in cells lacking RPS3 expression. RT-qPCR and immunofluorescence assays revealed that CSFV infection inhibited RPS3-mediated antiviral cytokine secretion. Taken together, these findings reveal that RPS3 is anovel antiviral factor that inhibits CSFV proliferation by increasing antiviral cytokine secretion. Keywords: classical swine fever virus; ribosome protein S3; IL-8; INF-β.

Development and performance evaluation of TaqMan real-time fluorescence quantitative methylation specific PCR for detecting methylation level of PER2.

PER2 gene methylation is closely related to the occurrence and progress of some cancers, but there is no method to quantitatively detect PER2 methylation in conventional laboratories. So, we established a TaqMan real-time fluorescence quantitative methylation specific PCR (TaqMan real-time FQ-MSP) assay and use it for quantitative detection of PER2 methylation in leukemia patients. According to the PER2 sequence searched by GenBank, a CpG sequence enrichment region of the PER2 gene promoter was selected, and the methylated and unmethylated target sequences were designed according to the law of bisulfite conversion of DNA to construct PER2 methylation positive and negative reference materials. Specific primers and probe were designed. The reference materials were continuously diluted into gradient samples by tenfold ratio to evaluate the analytical sensitivity, specificity, accuracy and reproducibility of the method, and the analytical sensitivity of TaqMan real-time FQ-MSP assay was compared with that of the conventional MSP assay. At the same time, the new-established TaqMan real-time FQ-MSP assay and the conventional MSP assay were used to detect the PER2 methylation level of 81 patients with leukemia, and the samples with inconsistent detection results of the two assays were sent to pyromethylation sequencing to evaluate the clinical detection performance. The minimum detection limit of TaqMan real-time FQ-MSP assay for detecting PER2 methylation level established in this study was 6 copies/uL, and the coefficient of variation(CV) of intra-assay and inter-assay was less than 3%. Compared with the conventional MSP assay, it has higher analytical sensitivity. For the samples with inconsistent detection results, the results of pyrosequencing and TaqMan real-time FQ-MSP assay are consistent. TaqMan real-time FQ-MSP assay of PER2 methylation established in this study has high detection performance and can be used for the detection of clinical samples.

A novel RHCE*cE allele identified in a Chinese individual, encodes weakened expression of c and E antigens

A novel RHCE*cE allele identified in a Chinese individual, encodes weakened expression of c and E antigens

Study of the Mechanism by Which Curcumin Cooperates with Sestrin2 to Inhibit the Growth of Pancreatic Cancer.

Background Pancreatic carcinoma is a malignant tumor with a high fatality rate, and the increased resistance of pancreatic carcinoma to chemotherapy has become a difficult problem in clinical practice. Hence, it is imperative to develop an effective treatment for pancreatic cancer. Sestrins are a class of stress-induced proteins that have antioxidation functions, regulating cell growth and metabolism. Curcumin is a natural pigment isolated from turmeric. Several studies have also suggested that this molecule has multiple pharmacological effects, such as anti-inflammatory, antioxidant, and antitumor effects. However, there are insufficient studies on curcumin cooperating with the sestrin family to inhibit tumors, and the mechanism is still unclear. Our aim was to observe the potential anticancer effects of curcumin combined with the sestrin family on pancreatic carcinoma and probe its possible molecular mechanisms. Methods Lentiviral infection, real-time fluorescence quantitative PCR assays, Cell Counting Kit-8 assays, real-time cell analysis technology, colony formation assays, wound healing assays, Transwell invasion assays, protein extraction, and western blots (WBs) were used to evaluate the effect of curcumin combined with sestrin2 on the proliferation, invasion, and migration of pancreatic carcinoma cells. Results The results revealed that curcumin cooperated with sestrin2 to significantly suppress pancreatic cancer. In addition, we determined that sestrin2 cooperated with curcumin to inhibit pancreatic cancer by specifically targeting Nrf2/Keap1/HO-1/NQO-1. Conclusion These findings clarify that curcumin-mediated synergistic targeting of sestrin2 is a potentially valuable treatment for pancreatic cancer.

A Real-Time Fluorescent Reverse Transcription Quantitative PCR Assay for Rapid Detection of Genetic Markers' Expression Associated with Fusarium Wilt of Banana Biocontrol Activities in Bacillus.

Fusarium wilt of banana, caused by Fusarium oxysporum f. sp. cubense (Foc), especially Tropical Race 4 (TR4), seriously threatens banana production worldwide. There is no single effective control measure, although certain Bacillus strains secrete antibiotics as promising disease-biocontrol agents. This study identified five Bacillus strains displaying strong antibiotic activity against TR4, using a systemic assessment for presence/absence of genetic markers at genome level, and expression profiles at transcriptome level. A conventional PCR with 13 specific primer pairs detected biocontrol-related genes. An accurate, quantitative real-time PCR protocol with novel designed specific primers was developed to characterise strain-specific gene expression, that optimises strain-culturing and RNA-isolation methodologies. Six genes responsible for synthesising non-ribosomal peptide synthetase biocontrol metabolites were detected in all five strains. Three genes were involved in synthesising three Polyketide synthetase metabolites in all five strains, but the macrolactin synthase gene mln was only detected in WBN06 and YN1282-2. All five Bacillus strains have the genes dhb and bioA, essential for synthesising bacillibactin and biotin. However, the gene sboA, involved in subtilisin synthesis, is absent in all five strains. These genes’ expression patterns were significantly different among these strains, suggesting different mechanisms involved in TR4 biocontrol. Results will help elucidate functional genes’ biocontrol mechanisms.

Expression and clinicopathological significance of Bcl - 2 and Bax genes in colorectal cancer patients complicated with schistosomiasis

To investigate the expression and clinicopathological significance of Bcl-2 and Bax genes in colorectal cancer (CRC) patients complicated with schistosomiasis. The CRC patients receiving surgical treatment in the First Affiliated Hospital of Dali University from June 2016 to June 2020 were recruited as the study subjects, and 30 subjects were randomly sampled from the CRC patients complicated with schistosomiasis (CRC-S group) and 30 subjects were randomly sampled from the CRC patients without schistosomiasis (CRC group) using a random number table method. The cancer specimens were sampled from subjects in the CRC-S and CRC groups, and the peri-cancer specimens were sampled from subjects in the CRC group. The Bcl-2 and Bax expression was quantified in cancer and peri-cancer specimens using a real-time fluorescent quantitative PCR (qPCR) assay and immunohistochemistry at transcriptional and translational levels, and the cell apoptosis was detected in cancer specimens using HE staining. A total of 60 subjects were enrolled, including 30 cases in the CRC group and 30 cases in the CRC-S group. There were no significant differences between the two groups in terms of gender distribution (χ2 = 0.271, P > 0.05), mean age (t = -0.596, P > 0.05), tumor growth pattern (χ2 = 0.275, P > 0.05), tumor location (χ2 = 4.008, P > 0.05), tumor invasion depth (χ2 = 0.608, P > 0.05), degree of tumor differentiation (χ2 = 0.364, P > 0.05), or presence of vascular metastasis (χ2 = 1.111, P > 0.05), while significant differences were seen between the two groups in terms of histological type, presence of lymph node metastasis and TMN staging (χ2 = 5.963, 8.297 and 5.711, all P values < 0.05). qPCR assay and immunohistochemistry quantified significantly higher Bcl-2 and Bax expression in cancer specimens from the CRC and CRC-S groups than in the peri-cancer specimens from the CRC group at both translational and transcriptional levels (all P values < 0.05), and higher Bcl-2 and lower Bax expression were seen in the cancer specimens from the CSC-S group than that from the CRC group (all P values < 0.05). In addition, the cell apoptotic rate was significantly greater in the cancer specimens in the CRC group than in the CRC-S group (42.00% vs. 23.35%; χ2 = 41.500, P = 0.000). Schistosomiasis may be involved in the development and progression of CRC through affecting Bcl-2 and Bax gene expression in the apoptosis signaling pathway.

Study on the mechanisms of the intestinal tight-junction destruction caused by Blastocystis hominis infection in rats

To explore the mechanism of the intestinal barrier damage caused by Blastocystis hominis infections in rats. Thirty SD rats were randomly divided into the control group, and the 1-, 3-, 6- and 9-week-infection groups, of 6 rats in each group. Rats in each infection group were orally infected with B. hominis trophozoites at a density of 2 × 108 parasites per rat, and the control group was given an equal volume of phosphate buffered saline solution. The 7-hour urine samples were collected 1, 3, 6 and 9 weeks post-infection for the measurement of the intestinal permeability. Then, rats were sacrificed using the cervical dislocation method, and the cecum specimens were collected for the detection of the intestinal epithelial cell permeability. The expression of tight junction-related Occludin and Claudin - 1 genes and apoptosis-related Bcl - 2 and Bax genes was quantified in cecum epithelial cells using the real-time fluorescent quantitative PCR (qPCR) assay, and cell apoptosis was detected in the rat cecum using the TdT-mediated dUTP nick-end labeling (TUNEL) assay. The median urinary lactolose to mannitol ratios were 0.29, 0.72, 0.44, 0.46 and 0.38 in the control group, and the 1-, 3-, 6- and 9-week-infection groups, respectively, and the difference was statistically significant (H = 12.09, P < 0.05). B. hominis invasion and epithelial injury were observed in intestinal epithelial cells of rats infected with B. hominis, and transmission electron microscopy displayed the destruction of tight junctions between intestinal epithelial cells. The relative expression of Occludin, Claudin-1, Bcl-2 and Bax genes was 1.04, 0.62, 0.71, 0.68 and 0.96; 1.03, 0.61, 0.63, 0.76 and 0.86; 1.08, 0.70, 0.75, 0.74 and 1.03; and 1.00, 1.57, 1.33, 1.35 and 1.10 in the control group and the 1-, 3-, 6- and 9-week-infection groups, respectively, and all differences were statistically significant (F = 2.86, 2.85, 3.37 and 4.45, all P values < 0.05). The median number of positive staining cells were 1.00, 13.00, 9.00, 3.50 and 1.00 in rat cecum specimens in the control group, and the 1-, 3-, 6- and 9-week-infection groups, respectively, and the difference was statistically significant (H = 22.95, P < 0.01). B. hominis infection may cause an increase in the rat intestinal permeability through triggering the apoptosis of intestinal epithelial cells to destroy the tight junction between intestinal epithelial cells, thereby destroying the intestinal barrier function.

&lt;p&gt;LINC00501 Inhibits the Growth and Metastasis of Lung Cancer by Mediating miR-129-5p/HMGB1&lt;/p&gt;

BackgroundThe function of LINC00501, a long-non-coding RNA (lncRNA), is unclear at present. According to the Cancer Genome Atlas (TCGA), LINC00501 is highly expressed in lung cancer (LC), but whether it can be adopted as a potential therapy target for LC still needs further research.MethodsThe expression of LINC00501 in LC was analyzed based on the TCGA, and a real-time fluorescent quantitative PCR assay was carried out to quantify LINC00501 in non-small-cell lung cancer (NSCLC). Additionally, bioinformatics analysis, luciferase reporter gene technique, and RNA immunoprecipitation (RIP) were employed to analyze the direct interaction between LINC00501 and miR-129-5p, and CCK-8 and Transwell assays and flow cytometry were employed to analyze the effects of LINC00501 on cell proliferation, invasion, and apoptosis. Furthermore, a Western blot assay was carried out to determine the protein level of HMGB1.ResultsLINC00501 was highly expressed in LC according to the database, and it was found that LINC00501 was upregulated in NSCLC specimens and cells, and the up-regulation indicated an unfavorable prognosis. Besides, knockdown of LINC00501 hindered the proliferation and invasion of NSCLC cells and intensified their apoptosis, and LINC00501 could be adopted as competitive endogenous RNA to regulate HMGB1 and tumorigenesis through miR-129-5p.ConclusionLINC00501 is overexpressed in LC and the overexpression indicates poor prognosis of patients. In addition, LINC00501 can inhibit the invasion and migration of LC by mediating miR-129-5p/HMGB1.

Peripheral blood mononuclear cell microRNA profiles in syphilitic patients with serofast status.

Syphilis is a chronic sexually transmitted disease caused by infection with Treponema pallidum, which can invade various system organs, leading to clinical manifestations such as neurosyphilis, ocular syphilis, and cardiovascular syphilis and seriously endangering human health. Serofast status is a common outcome after syphilis treatment that presents an important clinical problem. At present, the etiology of serofast status remains unknown. A systematic investigation of the microRNA (miRNA) expression profiles in peripheral blood mononuclear cells (PBMCs) of patients with serofast status or secondary syphilis and of healthy control subjects was conducted using small RNA-seq. The expression of miRNAs was further confirmed by real-time fluorescence quantitative PCR (qPCR) assays. The data reveal a specific miRNA expression profile that was displayed in cells from patients with serofast status. Known and novel predicted (np)-miRNAs were also identified and verified, such as miR-338-5p, np-miR-163, np-miR-128, np-miR-244, and np-miR-5, which together may be used as indicators for treatment evaluation. The functions of genes targeted by the miRNAs differentially expressed in serofast status patients were further analyzed; these genes were found to be involved in various biological functions, such as T-cell receptor signaling pathways, metabolism, and growth. Our study presents the first systematic landscape of miRNAs in PBMCs from patients with serofast status and proposes specific miRNAs linked with serofast status. Our results provide further evidence that serofast status is closely related to host immune function. Additionally, the miRNA expression profile in PBMCs of patients with serofast status generated by this work offers insight into the complex immune network in humans. We hope our results can provide new insights into the pathogenesis of serofast status.

MiR-140 inhibits classical swine fever virus replication by targeting Rab25 in swine umbilical vein endothelial cells

ABSTRACT Classical swine fever virus (CSFV) is one of the most important viral pathogens leading worldwide threats to pig industry. MicroRNAs (miRNAs) play important roles in regulating virus replication, but whether miRNAs affect CSFV infection is still poorly understood. In previous study, we identified four miRNAs that were down-regulated by CSFV in swine umbilical vein endothelial cells (SUVEC). In this study, miR-140, one of the most potently down-regulated genes was investigated. We found that the miRNA expression was significantly inhibited by CSFV infection. Subsequent studies revealed that miR-140 mimics significantly inhibited CSFV replication, while the inhibition of endogenous miR-140 enhanced CSFV replication. By using bioinformatics prediction, luciferase reporter system, real-time fluorescence quantitative PCR (RT-qPCR) and Western blot assays, we further demonstrated that miR-140 bind to the 3ʹ UTR of Rab25 mRNA to regulate its expression. We also analyzed the expression pattern of Rab25 in SUVECs after CSFV infection. The results showed that CSFV infection induced Rab25 expression. Finally, Rab25 was found to promote CSFV replication. In conclusion, this study demonstrated that CSFV inhibits miR-140 expression and miR-140 inhibits replication by binding to host factor Rab25.

QPCR and loop mediated isothermal amplification for rapid detection of Ustilago tritici.

Loose smut of wheat caused by the basidiomycete fungus Ustilago tritici, a seed-borne disease, is difficult to control because of the expanse of wheat planting area and difficulty in pathogen detection. In this study, real-time fluorescence quantitative PCR (qPCR) and loop-mediated isothermal amplification (LAMP) assays are used to rapidly amplify the DNA of U. tritici. Five pairs of primers for qPCR and two series primers for LAMP were designed. Primarily, the specificity of the primer was assessed by using genomic DNA of U. tritici, Fusarium graminearum, Blumeria graminis, Rhizoctonia cerealis, Puccinia striiformis, Bipolaris sorokiniana, and Alternaria solani as templates. Further, the amplification systems were optimized. Finally, the sensitivity of qPCR and LAMP assays were evaluated. The results showed that the primer Y-430 F/R, Y-307 F/R, Y-755 F/R, and Y-139 F/R for qPCR and primers L-139 and L-988 for LAMP could be used for U. tritici detection. In the sensitivity test, the detection limit of qPCR assay was identified as 10 pg μL−1 of genomic DNA, the detection limit for LAMP assay was 100 fg μL−1. We successfully performed qPCR and LAMP assays on wheat loose smut wheat samples. This paper establishes two methods for U. tritici detection, which can be used for diagnosis of wheat loose smut in the laboratory and in the field.

Identification of the optimal insertion site for expression of a foreign gene in an infectious hematopoietic necrosis virus vector.

Infectious hematopoietic necrosis virus (IHNV) was developed as a vector to aid the construction of vaccines against viral diseases such as viral hemorrhagic septicemia virus, spring viremia of carp virus, and influenza virus H1N1. However, the optimal site for foreign gene expression in the IHNV vector has not been determined. In the present study, five recombinant viruses with the green fluorescence protein (GFP) gene inserted into different genomic junction regions of the IHNV genomic sequence were generated using reverse genetics technology. Viral growth was severely delayed when the GFP gene was inserted into the intergenic region between the N and P genes. Real-time fluorescence quantitative PCR assays showed that the closer the GFP gene was inserted towards the 3' end, the higher the GFP mRNA levels. Measurement of the GFP fluorescence intensity, which is the most direct method to determine the GFP protein expression level, showed that the highest GFP protein level was obtained when the gene was inserted into the intergenic region between the P and M genes. The results of this study suggest that the P and M gene junction region is the optimal site within the IHNV vector to express foreign genes, providing valuable information for the future development of live vector vaccines.

Sporamin suppresses growth of xenografted colorectal carcinoma in athymic BALB/c mice by inhibiting liver β-catenin and vascular endothelial growth factor expression.

BACKGROUNDColorectal cancer (CRC) is the third most common malignancy of the digestive tract and the fifth leading cause of cancer-related mortality in China. Sporamin, a Kunitz-type trypsin inhibitor isolated from sweet potato, is a potential anti-cancer agent with activities against a number of malignant tumor cells in vitro. The liver secretes a myriad of endocrine factors that may facilitate the growth and transformation of tumors in the development of CRC.AIMTo investigate the effects of sporamin on liver morphology and biomarkers of xenografted CRC in the liver of athymic BALB/c mice.METHODSTwenty-seven male BALB/c nude mice were randomly divided into control, vehicle, and sporamin groups. Mice in the latter two groups were intraperitoneally xenografted with LoVo colorectal carcinoma cells and intragastrically infused with saline or sporamin (0.5 g/kg body weight/d), respectively, for 3 wk. Hematoxylin and eosin (HE) staining of the sections was performed to observe morphological changes in hepatic tissue and real-time fluorescent quantitative PCR (qPCR) and enzyme-linked immunosorbent assay (ELISA) were used to measure the expression of β-catenin and vascular endothelial growth factor (VEGF) in the liver.RESULTSSporamin significantly reduced the number and weight of tumor nodules formed in the abdominal cavity. Compared with the vehicle group, the mean tumor weight (± SD) in the sporamin group was significantly reduced (0.44 ± 0.10 g vs 0.26 ± 0.15 g) and the total number of tumors decreased from 93 to 55. HE staining showed that enlargement of the nucleus and synthesis of proteins within hepatocytes, as well as infiltration of inflammatory cells into the liver, were attenuated by sporamin. Immunohistochemical staining and ELISA showed that the concentrations of β-catenin and VEGF in the liver were significantly reduced by sporamin. Compared with the vehicle group, the expression of β-catenin measured in integrated optical density units per area was reduced in the sporamin group (47.29 ± 9.10 vs 26.14 ± 1.72; P = 0.003). Expression of VEGF was also reduced after sporamin intervention from 20.78 ± 2.06 in the vehicle group to 15.80 ± 1.09 in the sporamin group (P = 0.021). Compared with the vehicle group, the concentration of β-catenin decreased from 134.42 ± 22.04 pg/mL to 109.07 ± 9.65 pg/mL after sporamin intervention (P = 0.00002). qPCR indicated that compared to the vehicle group, relative mRNA expression of β-catenin and VEGF in the liver of mice in the sporamin-treated group was significantly reduced to 71% ± 1% (P = 0.000001) and 23% ± 7% (P = 0.00002), respectively, of the vehicle group levels.CONCLUSIONSporamin down-regulates the expression and secretion of β-catenin and VEGF in the liver, which subsequently inhibits the transcription of downstream genes involved in cancer progression and angiogenesis.

Phenotypic and genetic analysis of a sibpair with partial deletion of SATB2 gene caused by 2q33.1 microdeletion

To analyze the genotype and phenotype of a sibpair with partial deletion of SATB2 gene caused by 2q33.1 microdeletion. Both children have featured mental retardation and development delay, and were subjected to karyotyping, single nucleotide microarray (SNP array) and real-time fluorescence quantitative PCR analysis. Karyotyping and SNP Array analysis were also carried out on their parents to verify the origin of mutation. Both sibs had a normal karyotype. SNP array showed that sib 1 had arr[hg19]2q33.1(200 192 328 - 200 197 269)×1 (4.9 kb), 2q35 (218 105 663 - 218 816 675)×3 (711 kb), while sib 2 had arr[hg19]2q33.1(200 192 328 - 200 197 269)×1 (4.9 kb), 2q35 (218 105 663-218 810 908)×3 (705.2 kb). The deletion has partially overlapped with that of 2q33.1 microdeletion syndrome and involved part of the SATB2 gene. The result of real-time fluorescence quantitative PCR assay was consistent with that of SNP assay. The duplication has originated from their father and has not been associated with any disease phenotypen. Both sibs have carried partial deletion of SATB2 gene and had similar clinical phenotypes. Haploinsufficiency of such gene probably underlies the clinical manifestations in both patients.

Development of a TB green II-based duplex real-time fluorescence quantitative PCR assay for the simultaneous detection of porcine circovirus 2 and 3

Porcine circovirus 3 (PCV3), as a newly emerged circovirus, is widely distributed in pig populations worldwide. Co-infection of PCV2 and PCV3 has been reported frequently in clinical samples. In the present study, a TB Green II-based duplex real-time polymerase chain reaction (qPCR) was developed to rapidly and differentially detect PCV2 and PCV3. The assay specifically detected PCV2 and PCV3, with no fluorescence signals being detected for other non-targeted pig pathogens. The duplex qPCR showed a high degree of linearity (R2 > 0.998), and its limits of detection were 10 and 78 copies/μL for PCV2 and PCV3, respectively. The duplex qPCR could detect and differentiate PCV2 (melting peaks at 85.5 °C) and PCV3 (melting peaks at 82.5 °C), and showed high repeatability and reproducibility, with intra- and inter-assay coefficients of variation of less than 2.0%. Fifty-six tissue samples from 18 pig farms were used to evaluate the duplex qPCR method. The results revealed infection rates of 66.07% (37/56) and 39.28% (22/56) for PCV2 and PCV3, respectively. The PCV2 + PCV3 co-infection rate was 39.28% (22/56). The developed method could be used as an efficient molecular biology tool for epidemiological investigations of PCV2 and PCV3.

Development of a SYBR green I-based duplex real-time fluorescence quantitative PCR assay for the simultaneous detection of porcine epidemic diarrhea virus and porcine circovirus 3

The development of a rapid, specific, and sensitive SYBR Green I-based duplex real-time quantitative PCR assay is described for the simultaneous detection of porcine epidemic diarrhea virus (PEDV) and porcine circovirus type 3 (PCV3). The assay specifically detected PEDV and PCV3, with no fluorescence detected for other non-targeted pig pathogens. The assay showed a good linear relationship, and the limits of detection for this assay were 34.6 copies/μL and 61.2 copies/μL for PEDV and PCV3, respectively. The assay exhibited high repeatability and reproducibility, with intra-assay and inter-assay variation coefficients less than 2.0%. A clinical evaluation using intestinal tissue and fecal samples from piglets suffering from diarrhea at different pig farms in China revealed that the singular infection rates of PEDV and PCV3 were 43.94% (29/66) and 16.67% (11/66), respectively, while the co-infection rate of PCV3 with PEDV was 27.27% (18/66). The results indicate this assay is a rapid and reliable diagnostic tool for PEDV and PCV3 monitoring and surveillance in the field, and provides technical support for the quantitative detection of clinical samples infected or co-infected with PEDV and PCV3.

The role and mechanism of S100 calcium binding protein B in osteoarthritis cartilage damage repair

To investigate the role and mechanism of S100 calcium binding protein B (S100B) in osteoarthritis (OA) cartilage damage repair. Twenty New Zealand rabbits were randomly divided into control group and model group, with 10 rabbits in each group. Rabbits in the model group were injured by the right knee joint immobilization method to make the artilage injury model, while the control group did not deal with any injury. After 4 weeks, the levels of interleukin-1β (IL-1β) and tumor necrosis factor α (TNF-α) in synovial fluid were detected by ELISA method; the mRNA and protein expressions of S100B, fibroblast growth factor 2 (FGF-2), and FGF receptor 1 (FGFR1) in cartilage tissue were examined by real-time fluorescence quantitative PCR (qRT-PCR) and Western blot assay. Human synovial fibroblasts (SF) were isolated and cultured in vitro. The effects of S100B overexpression and knockdown on the levels of IL-1β and TNF-α (ELISA method) and the expressions of FGF-2 and FGFR1 gene (qRT-PCR) and protein (Western blot) were observed. Moreover, the effects of FGFR1 knockdown in above S100 overexpression system on the levels of IL-1β and TNF-α (ELISA method) and the expressions of FGF-2 and FGFR1 gene (qRT-PCR) and protein (Western blot) were observed. ELISA detection showed that the expressions of IL-1β and TNF-α in the synovial fluid of the model group were significantly higher than those of the control group ( P<0.05); qRT-PCR and Western blot detection showed that the mRNA and protein expressions of S100B, FGF-2, and FGFR1 in cartilage tissue were significantly higher than those of the control group ( P<0.05). Overexpression and knockdown S100 could respectively significantly increase and decrease lipopolysaccharides (LPS) induced IL-1β and TNF-α levels elevation and the mRNA and protein expressions of FGF-2 and FGFR1 ( P<0.05); whereas FGFR1 knockdown could significantly decrease LPS induced IL-1β and TNF-α levels elevation and the mRNA and protein expressions of FGF-2 and FGFR1 ( P<0.05). S100B protein can regulate the inflammatory response of SF and may affect the repair of cartilage damage in OA, and the mechanism may be related to the activation of FGF-2/FGFR1 signaling pathway.

Changes of mitochondrial dynamics related genes expression in a glaucoma rat model

Objective To investigate the ultrastructural changes of mitochondria and dynamic changes of mitochondrial dynamics related genes in chronic ocular hypertension rat models. Methods Forty Sprague-Dawley (SD) rats were randomized into normal control group, modeling 3 day-group, modeling 7 day-group and modeling 14 day-group.Glaucoma models were induced by translimbal laser photocoagulation of trabecular meshwork in rats.The number of survival retinal ganglion cells was evaluated by retrogradely labeling of FluoroGold.The morphological change of mitochondria in optical nerve was observed under the transmission microscope.The dynamic changes of mitochondrial dynamic-related gene expression in the retina in gene and protein levels were detected by real-time fluorescence quantitative PCR and Western blot assay, respectively.The experiment complied ARVO Statement for the Use of Animals in Ophthalmic and Vision Research and approved by the Animal Experimentation Ethics Committee of the Eye and ENT Hospital of Fudan University. Results The intraocular pressure was significantly higher in the modeling 3-day group, modeling 7-day group and modeling 14-day group than that in the normal control group (all at P<0.01). Compared with the normal control group, the immunoreactivity of glial fibrillary acidic protein (GFAP) was increased in the Muller cells in all modeling retinas, and the relative expressing levels of GFAP protein were significantly mcreased in all modeling groups (F=91.47, 17.58, both at P<0.01). Compared to the normal control group, the number of mitochondria was increased, and the mitochondrial health degree in the optic nerve and the nearest neighbor distance between adjacent mitochondria were decreased in the modeling 3- day group and 14-day group (all at P<0.05). The expression levels of dynamics-related protein 1(Drp1), parkin protein, PINK1, KIF5B and Miro1 mRNA in the retina were significantly elevated in the modeling 3-day group (all at P<0.05). In addition, the expression levels of optineurin, parkin and OPA1 proteins were higher in the modeling 3-, 7- and 14-day groups than those in the normal control group (all at P<0.05). Conclusions Dysfunction of mitochondria and changes of mitochondrial dynamics exist in RGCs of glaucomatous rats, including increased mitochondrial fission and fusion as well as the activation of mitophagy pathway, which probably are the mechanism of RGC damage in glaucoma. Key words: Mitochondria; Glaucoma; Fission; Fusion; Mitophagy; Retinal ganglion cells; Animal models; SD rats

Evaluation of performance and application of three nucleic acid extraction methods for quantification of plasma Epstein-Barr virus DNA

Objective To evaluate and compare the analytical performances and application values of three nucleic acid extraction methods for quantification of plasma Epstein-Barr Virus (EBV) DNA. Methods It used silica membrane spin column, boiling and automated magnetic bead method to extract viral nucleic acid in parallel, and combined real-time fluorescence quantitative PCR assays for quantitative EBV-DNA quantification.The performances of three methods were determined and compared by using the third-party reference materials, and the clinical values were analyzed by pairing detecting 100 NPC patients and 100 healthy subjects in pair. Results The accuracy and imprecision of three methods were all in line with requirements, and the results of clinical samples were linearly correlated. But actually the reproducibility and intermediate imprecision of the magnetic bead method were smaller and stable than those of the spin column method and the boiling method (all <3%); the limit of detection for the magnetic bead method was 3.334×101 IU/ml, better than that of spin column method (4.159×101 IU/ml) and boiling method (8.511×101 IU/ml); the linear range of the magnetic bead method was 5.4×101-5.4×105 IU/ml, slightly wider than that of the boiling method(5.4×102-5.4×105 IU/ml); the ability of anti - Hb interference ability of magnetic bead method is better than that of boiling method; and the positive rate and the mean viral load of the NPC samples measured with the magnetic bead method were significantly higher (95%, 8.342×103 IU/ml) than those measured with the spin column method (84%, 4.707×103 IU/ml) and the boiling method (78%, 2.571×103 IU/ml) (P all<0.05). Conclusion The automated magnetic bead nucleic acid extraction method offered better analytical performance and higher clinical value for EBV DNA quantification in plasma.(Chin J Lab Med, 2018, 41: 59-65) Key words: Herpesvirus 4, human; DNA, viral; Centrifugation; DNA cleavage; Automation, laboratory; Clinical laboratory techniques; Evaluation studies

Development of real-time fluorescence quantitative PCR for the detection of Moraxella catarrhalis

Objective To developed A laboratory diagnosis of Moraxella catarrhalis by an laboratories diagnostic method real-time fluorescence quantitative PCR assay. Methods The specific primers and probes were designed based on the sequence of outer membrane protein CopB(copB)gene in Moraxella catarrhalis, and the Taqman probe RT-PCR method was developed to detect the Moraxella catarrhalis.The standard plasmids extracted from the Moraxella catarrhalis standard strains were used to constitute the standard samples, and compared with these standard samples, the sensitivity of the fluorescence quantitative PCR assay was tested by the established standard curves.The specificity of the fluorescence quantitative PCR assay was tested by the DNA samples of other bacterias in the laboratory.Meanwhile, 321 throat swab samples from inpatient and outpatient child patients, with asthma infection were collected as clinical samples to validate the fluorescence quantitative PCR assay. Results The standard curve was drawn in the real-time PCR by the Taqman fluorescence reporter.During the sensitivity tests, the newly-developed real-time fluorescence PCR could detect at least 10 copies of Moraxella catarrhalis, and could successfully distinguish several DNAs of the pathogens.On the basis of the validation result of the 321 throat swab samples, there are 25 Moraxella catarrhalis with 7.79 % positive rate. Conclusion The fluorescence quantitative PCR assay is of great sensitivity and specificity, and it can be widely used for the detection of Moraxella catarrhalis. Key words: Moraxella catarrhalis; Respiratory tract infections in children; Real-time fluorescence quantitative PCR