AIM: To study the relationship between hepatitis B virus (HBV) DNA levels and liver histology in patients with chronic hepatitis B (CHB) and to determine the prevalence and characteristics of hepatitis B e antig...AIM: To study the relationship between hepatitis B virus (HBV) DNA levels and liver histology in patients with chronic hepatitis B (CHB) and to determine the prevalence and characteristics of hepatitis B e antigen (HBeAg) negative patients.METHODS: A total of 213 patients with CHB were studied, and serum HBV DNA levels were measured by the COBAS Amplicor HBV Monitor test. All patients were divided into two groups according to the HBeAg status.The correlation between serum HBV DNA levels and liver damage (liver histology and biochemistry) was explored.RESULTS: Of the 213 patients with serum HBV DNA levels higher than 10^5 copies/mL, 178 (83.6%) were HBeAg positive, 35 (16.4%) were HBeAg negative. The serum HBV DNA levels were not correlated to the age,history of CHB, histological grade and stage of liver disease in either HBeAg negative or HBeAg positive patients. There was no correlation between serum levels of HBV DNA and alanine aminotransferanse (ALT),aspartate aminotrans-ferase (AST) in HBeAg positive patients. In HBeAg negative patients, there was no correlation between serum levels of HBV DNA and AST,while serum DNA levels correlated with ALT (r = 0.351, P = 0.042). The grade (G) of liver disease correlated with ALT and AST (P 〈 0.05, r = 0.205, 0.327 respectively)in HBeAg positive patients. In HBeAg negative patients,correlations were shown between ALT, AST and the G (P 〈 0.01, and r = 0.862, 0.802 respectively). HBeAg negative patients were older (35 ± 9 years vs 30 ±9 years, P 〈 0.05 ) and had a longer history of HBV infection (8 ± 4 years vs 6 ± 4 years, P 〈 0.05) and a lower HBV DNA level than HBeAg positive patients (8.4± 1.7 Log HBV DNA vs 9.8 ± 1.3 Log HBV DNA, P 〈0.001). There were no significant differences in sex ratio,ALT and AST levels and liver histology between the two groups.CONCLUSION: Serum HBV DNA level is not correlated to histological grade or stage of liver disease in CHB patients with HBV DNA more than 10^5 copies/mL.Compared to HBeAg positive patients, HBeAg negative patients are older and have a lower HBV DNA level and a longer HBV infection history. There is no significant difference in sex ratio, ALT and AST levels and liver histology between the two groups.展开更多
Hepatitis B is a major health concern in the Asia-Pacific region, and is endemic in China, Southeast Asia, and Africa. Chronic hepatitis B virus (HBV) infection may cause hepatic cirrhosis and liver cancer. It is esti...Hepatitis B is a major health concern in the Asia-Pacific region, and is endemic in China, Southeast Asia, and Africa. Chronic hepatitis B virus (HBV) infection may cause hepatic cirrhosis and liver cancer. It is estimated that there are more than 350 million chronic HBV carriers worldwide, of whom approximately one quarter will die of chronic hepatitis B-related liver diseases. HBV is transmitted horizontally through blood and blood products or by sexual transmission, and vertically from mother to infant. Perinatal infection is the predominant mode of transmission in countries with a high prevalence of hepatitis B surface antigen (HBsAg) carriage, and perinatal transmission leads to high rates of chronic infection. Therefore, it is important to prevent the mother-to-child transmission (MTCT) of HBV. Research has shown that pregnant women with high HBV DNA levels have an increased risk of MTCT. However, most of the obstetrics guidelines do not make a distinction between pregnant women with high HBV DNA levels and those who are HBsAg positive only. This review addresses the management of pregnant women with high levels of HBV viremia, in terms of antiviral therapy, use of hepatitis B immunoglobulin (HBIG), the combined application of hepatitis B vaccine and HBIG, choice of delivery mode and feeding practices. (C) 2014 Baishideng Publishing Group Inc. All rights reserved.展开更多
AIM:To investigate the peripheral T-lymphocyte subpopulation profile,and its correlations with hepatitis B virus(HBV) replication level in chronic HBV-infected(CHI) individuals with normal liver function tests(LFTs) ....AIM:To investigate the peripheral T-lymphocyte subpopulation profile,and its correlations with hepatitis B virus(HBV) replication level in chronic HBV-infected(CHI) individuals with normal liver function tests(LFTs) . METHODS:Frequencies of T-lymphocyte subpopu-lations in peripheral blood were measured by flow cytometry in 216 CHI individuals. HBV markers were detected with ELISA. Serum HBV DNA load was assessed with quantitative real-time PCR. Information of age at HBV infection,and maternal HBV infection status was collected. ANOVA linear trend test and linear regression were used in statistical analysis. RESULTS:CHI individuals had significantly decreased relative frequencies of CD3+,CD4+ subpopulationsand CD4+/CD8+ ratio,and increased CD8+ subset percentage compared with uninfected individuals(all P < 0.001) . There was a significant linear relationship between the load of HBV DNA and the parameters of T-lymphocyte subpopulations(ANOVA linear trend test P < 0.01) . The parameters were also significantly worse among individuals whose mothers were known to be HBV carriers,and those having gained infection before the age of 8 years. In multiple regressions,after adjustment for age at HBV infection and status of maternal HBV infection,log copies of HBV DNA maintained its highly significant predictive coefficient on T-lymphocyte subpopulations,whereas the effect of HBeAg was not significant. CONCLUSION:HBV DNA correlates with modification in the relative T-lymphocyte subpopulation frequencies. High viral load is more powerful than HBeAg in predicting the impaired balance of T-cell subsets.展开更多
BACKGROUND Chronic hepatitis B virus(HBV)infection remains a major global public health problem.Chronic hepatitis B(CHB)patients can be divided into treatment indication and non-treatment indication individuals accord...BACKGROUND Chronic hepatitis B virus(HBV)infection remains a major global public health problem.Chronic hepatitis B(CHB)patients can be divided into treatment indication and non-treatment indication individuals according to alanine transaminase(ALT),HBV DNA,serum hepatitis B e antigen status,disease status[liver cirrhosis,hepatocellular carcinoma(HCC),or liver failure],liver necroinflammation or fibrosis,patients’age,and family history of HCC or cirrhosis.For example,normal ALT patients in‘immune-tolerant’phase with HBV DNA higher than 10^(7)or 2×10^(7)IU/mL,and those in‘inactive-carrier’phase with HBV DNA lower than 2×10^(3)IU/mL do not require antiviral therapy.However,is it reasonable to set the defined values of HBV DNA as the fundamental basis to estimate the disease state and to determine whether to start treatment?In fact,we should pay more attention to those who do not match the treatment indications(grayzone patients both in the indeterminate phase and in the‘inactive-carrier’phase).AIM To analyze the correlation of HBV DNA level and liver histopathological severity,and to explore the significance of HBV DNA for CHB with normal ALT.METHODS From January 2017 to December 2021,a retrospective cross-sectional set of 1299 patients with chronic HBV infection(HBV DNA>30 IU/mL)who underwent liver biopsy from four hospitals,including 634 with ALT less than 40 U/L.None of the patients had received anti-HBV treatment.The degrees of liver necroinflammatory activity and liver fibrosis were evaluated according to the Metavir system.On the basis of the HBV DNA level,patients were divided into two groups:Low/moderate replication group,HBV DNA≤10^(7)IU/mL[7.00 Log IU/mL,the European Association for the Study of the Liver(EASL)guidelines]or≤2×10^(7)IU/mL[7.30 Log IU/mL,the Chinese Medical Association(CMA)guidelines];high replication group,HBV DNA>10^(7)IU/mL or>2×10^(7)IU/mL.Relevant factors(demographic characteristics,laboratory parameters and noninvasive models)for liver histopathological severity were analyzed by univariate analysis,logistics analysis and propensity score-matched analysis.RESULTS At entry,there were 21.45%,24.29%,and 30.28%of the patients had liver histopathological severities with≥A2,≥F2,and≥A2 or/and≥F2,respectively.HBV DNA level(negative correlation)and noninvasive model liver fibrosis 5 value(positive correlation)were independent risk factors for liver histopathological severities(liver necroinflammation,liver fibrosis,and treatment indication).The AUROCs of the prediction probabilities(PRE_)of the models mentioned above(<A2 vs≥A2,<F2 vs≥F2,<A2 and<F2 vs≥A2 or/and≥F2)were 0.814(95%CI:0.770-0.859),0.824(95%CI:0.785-0.863),and 0.799(95%CI:0.760-0.838),respectively.HBV DNA level(negative correlation)was still an independent risk factor when diagnostic models were excluded,the P values(<A2 vs≥A2,<F2 vs≥F2,<A2 and<F2 vs≥A2 or/and≥F2)were 0.011,0.000,and 0.000,respectively.For the propensity score-matched pairs,whether based on EASL guidelines or CMA guidelines,the group with significant liver histology damage(≥A2 or/and≥F2)showed much lower HBV DNA level than the group with non-significant liver histology damage(<A2 and<F2).Patients in the moderate replication group(with indeterminate phase)had the most serious liver disease pathologically and hematologically,followed by patients in the low replication group(with‘inactive-carrier’phase)and then the high replication group(with‘immune-tolerant’phase).CONCLUSION HBV DNA level is a negative risk factor for liver disease progression.The phase definition of CHB may be revised by whether the level of HBV DNA exceeds the detection low limit value.Patients who are in the indeterminate phase or‘inactive carriers’should receive antiviral therapy.展开更多
AIM To investigate and compare the analytical and clinical performance of Tian Long automatic hypersensitive hepatitis B virus(HBV) DNA quantification system and Roche CAP/CTM system.METHODS Two hundred blood samples ...AIM To investigate and compare the analytical and clinical performance of Tian Long automatic hypersensitive hepatitis B virus(HBV) DNA quantification system and Roche CAP/CTM system.METHODS Two hundred blood samples for HBV DNA testing, HBV-DNA negative samples and high-titer HBV-DNA mixture samples were collected and prepared. National standard materials for serum HBV and a worldwide HBV DNA panel were employed for performance verification. The analytical performance, such as limit of detection, limit of quantification, accuracy, precision, reproducibility, linearity, genotype coverage and cross-contamination, was determined using the Tian Long automatic hypersensitive HBV DNA quantification system(TL system). Correlation and Bland-Altman plot analyses were carried out to compare the clinical performance of the TL system assay and the CAP/CTM system. RESULTS The detection limit of the TL system was 10 IU/m L, and its limit of quantification was 30 IU/m L. The differences between the expected and tested concentrations of the national standards were less than ± 0.4 Log10 IU/m L, which showed high accuracy of the system. Results of the precision, reproducibility and linearity tests showed that the multiple test coefficient of variation(CV) of the same sample was less than 5% for 102-106 IU/m L; and for 30-108 IU/m L, the linear correlation coefficient r2 = 0.99. The TL system detected HBV DNA(A-H) genotypes and there was no cross-contamination during the "checkerboard" test. When compared with the CAP/CTM assay, the two assays showed 100% consistency in both negative and positive sample results(15 negative samples and 185 positive samples). No statistical differences between the two assays in the HBV DNA quantification values were observed(P > 0.05). Correlation analysis indicated a significant correlation between the two assays, r2 = 0.9774. The Bland-Altman plot analysis showed that 98.9% of the positive data were within the 95% acceptable range, and the maximum difference was-0.49.CONCLUSION The TL system has good analytical performance, and exhibits good agreement with the CAP/CTM system in clinical performance.展开更多
Objective:Circulating cell-free Epstein-Barr virus(EBV)DNA has been shown to be a valuable biomarker for population screening and prognostic surveillance for nasopharyngeal carcinoma(NPC).Despite important insights in...Objective:Circulating cell-free Epstein-Barr virus(EBV)DNA has been shown to be a valuable biomarker for population screening and prognostic surveillance for nasopharyngeal carcinoma(NPC).Despite important insights into the biology of persistence,few studies have addressed the clinical significance of cell-based EBV-DNA loads in peripheral blood cells(PBCs).Methods:A prospective observational cohort study was conducted involving 1,063 newly diagnosed,locoregionally-advanced NPC patients at Sun Yat-sen University Cancer Center from 2005 to 2007.Cox regression analysis was conducted to identify the association of PBC EBV DNA loads to overall survival(OS)and other prognostic outcomes.Prognostic nomograms were developed based on PBC EBV DNA loads to predict survival outcomes for NPC patients.Results:After a median follow-up of 108 months,patients with higher PBC EBV-DNA loads had significantly worse OS[hazard ratio(HR)of medium,medium-high,and high vs.low were 1.50,1.52,and 1.85 respectively;Ptrend<0.001].Similar results were found for progression-free survival and distant metastasis-free survival.The concordance index of the prognostic nomogram for predicting OS in the training set and validation set were 0.70 and 0.66,respectively.Our data showed that the PBC EBV DNA load was an independent and robust survival biomarker,which remained significant even after adjusting for plasma EBV DNA loads in a subset of 205 patients of the cohort(HR:1.88;P=0.025).Importantly,a combination of PBC EBV DNA load and plasma EBV DNA load improved the predicted OS.Conclusions:The EBV-DNA load in PBCs may be an independent prognosis marker for NPC patients.展开更多
Duck hepatitis B vims (DHBV) DNA was detected in different tumorous nodules of ducks with hepatic multicentric cancer or intrahepatic metastasis by Southern blot technique. Among 7 ducks with hepatocellular carcinoma ...Duck hepatitis B vims (DHBV) DNA was detected in different tumorous nodules of ducks with hepatic multicentric cancer or intrahepatic metastasis by Southern blot technique. Among 7 ducks with hepatocellular carcinoma of multiple tumor nodules, the hybridization pattern of Integrated DHBV DNA In different tumorous nodules was identical in 3 cases and different in 2 cases. One case showed a similar hybridization pattern in two tumorous nodules and other one was negative tor DHBV DNA. Integrated DHBV DNA was also identified in a metastatic lung cancer of ducks with hepatocellular carcinoma. The hybridization pattern of metastasis of lungs was as the some as that in primary hepatocellular carcinoma. The same discrete hybridization bands In the different tumorous nodules indicate that these nodules might arise from one transformed cell. The different hybridization patterns In various tumorous nodules show that these tumorous nodules might arise from various transformed cells. The results suggest that the hybridization pattern of different nodules of hepatocellular carcinoma with viral DNA probe could make a cell clone origin marker of tumor nodule to differentiate hepatic multlcentric cancer from Intrahepatic metastatic cancer.展开更多
Objective:To investigate the disparities and associations between HBV DNA and HBV RNA in various liver disease groups with respect to HBeAg status.Methods:Between September 2020 and September 2023,90 patients diagnose...Objective:To investigate the disparities and associations between HBV DNA and HBV RNA in various liver disease groups with respect to HBeAg status.Methods:Between September 2020 and September 2023,90 patients diagnosed with chronic hepatitis B(CHB),74 patients diagnosed with liver cirrhosis(LC),and 102 patients diagnosed with hepatocellular carcinoma(HCC)from the Department of Gastroenterology or Infection at the First Affiliated Hospital of Xi’an Jiaotong University were selected.HBV DNA,HBV RNA,and HBeAg quantitative tests were conducted using serum samples from the same patients.Results:In the three groups of cases,the HBV RNA load was higher when HBeAg was positive than when HBeAg was negative,and this difference was statistically significant.Only in the HCC group was the HBV DNA load significantly higher when HBeAg was positive than when HBeAg was negative.Additionally,there was a positive correlation between HBV DNA and HBV RNA regardless of HBeAg status.Conclusion:During HBeAg conversion,HBV RNA demonstrates a more sensitive response than HBV DNA.As CHB progresses to LC or HCC,HBV RNA exhibits better diagnostic value than HBV DNA.展开更多
AIM: To clarify the effect of SEN virus (SENV) infection on a combination therapy including interferon alfa (IFN-α) or pegylated-IFN with ribavirin in patients with chronic hepatitis and the effect of a combination t...AIM: To clarify the effect of SEN virus (SENV) infection on a combination therapy including interferon alfa (IFN-α) or pegylated-IFN with ribavirin in patients with chronic hepatitis and the effect of a combination therapy on SENV.METHODS: SENV DNA was determined by polymerase chain reaction in serum samples from 95 patients with chronic hepatitis C. Quantitative analysis was done for SENV H DNA.RESULTS: Twenty-one (22%) of 95 patients were positive for SENV DNA. There was no difference in clinical and biochemical parameters between patients with HCV infection alone and coinfected patients. The sustained response rate for HCV clearance after combination therapy did not differ between patients with SENV (52%) and without SENV(50%, n.s.). SENV DNA was undetectable in 76% of the initially SENV positive patients at the end of follow-up. SENV H response to combination therapy was significantly correlated with SENV DNA level (P=-0.05).CONCLUSION: SENV infection had no influence on the HCV sustained response rate to the combination therapy.Response rate of SENV to the combination therapy depends on SENV DNA level.展开更多
Objective This study aimed to investigate the prevalence of Epstein-Barr virus(EBV)infection in patients with and without cancer.Methods A total of 26,648 participants who underwent whole-blood EBV DNA(WBEBV)assays be...Objective This study aimed to investigate the prevalence of Epstein-Barr virus(EBV)infection in patients with and without cancer.Methods A total of 26,648 participants who underwent whole-blood EBV DNA(WBEBV)assays between January 1,2020,and August 31,2023,were included.The chi-square test was used for categorical data analysis,and R software was used to analyze the differences in EBV DNA load levels and the diagnostic capabilities of WBEBV.Results Positive rates were 10.2%and 25.4%for healthy controls(HC)and patients,respectively.The positivity rate for EBV-associated neoplasms(EN)was the highest at 7.53%,followed by leukemia(Le)at 5.49%.The subgroup analysis showed that the positivity rate for abnormal proliferation or hyperplasia(APH)was 31.9%,followed by 30.5%for Le.The WBEBV of patients with transplants(TP),especially living-related transplants(LT),was the highest among all subgroups.WBEBV at diagnosis was used to differentiate between infectious mononucleosis(IM)and chronic active Epstein-Barr virus(CAEBV),with a sensitivity of 67.4%(95%confidence interval[CI]:57.6-75.8)and specificity of 72%(95%CI:63.3-79.3).We conclude that the prevalence of EBV infection is low in the healthy population in this region and that a high EBV load at baseline is more common in LT,IM,and Lymphocyte Leukemia(LL).Conclusion This study used a large-sample survey to characterize the prevalence of whole-blood EBV levels in various diseases,including the stages and subtypes.The EBV detection rate was higher in patients with malignant disease than in those with benign disease.Our study provides clinicians with baseline information regarding EBV-associated diseases.展开更多
AIM To explore a rapid and easy sequencing method for hepatitis C virus (HCV) genome, and establish a new sequencing method in China. METHODS Polymerase Chain Reaction (PCR) was combined with DNA sequencing techn...AIM To explore a rapid and easy sequencing method for hepatitis C virus (HCV) genome, and establish a new sequencing method in China. METHODS Polymerase Chain Reaction (PCR) was combined with DNA sequencing technique. PCR products were purified by agarose gel electrophoresis, polyacrylamide gel electrophoresis (PAGE), Polyethylene glycol (PEG) respectively. Then in the presence of a 5′ labeling PCR primer, purified PCR products were directly sequenced. By this method, HCV NS5b cDNA from two HCV infected individuals (HC 42 and HC 49) were sequenced.展开更多
Banana bunchy top virus Chinese Zhangzhou isolate (BBTV-ZZ) DNA 4 was amplified by PCR and cloned. Sequence analysis showed that BBTV-ZZ DNA 4 is 1 039 nucleotides (nts) in length and this virus could be one member of...Banana bunchy top virus Chinese Zhangzhou isolate (BBTV-ZZ) DNA 4 was amplified by PCR and cloned. Sequence analysis showed that BBTV-ZZ DNA 4 is 1 039 nucleotides (nts) in length and this virus could be one member of BBTV Asian group. Transcriptional initiation site A, which is at the 269 nucleotide, was preliminarily determined by using 5' RACE method. BBTV-ZZ DNA 4 non-coding region was sub-cloned by PCR and inserted into upstream of gfp : : gus plant expression vector pCAMBIA 1304 to construct recombinant plasmid pTA2. Agrobacterium tumefaciens harboring pTA2 was injected into leaves of the tobacco (Nicotiana tabacum L. cv. Xanthi NC) via Agrobacterium-infiltration procedure. Transient expressions of GUS and GFP were determined in injected leaves 3 - 5 d later. GUS activities of pTA2, pCAMBIA 1304 injected and non-injected tobacco leaves respectively were 1.007 0 pmol MU(.)mug(-1.)min(-1), 2.069 0 pmol MU(.)mug(-1.)min(-1) and 0.021 4 pmol MU(.)mug(-1.)min(-1). Indirect ELISA for GFP in 1 mg total protein from pTA2, pCAMBIA 1304 injected and non-injected leaves showed an A(490 nm) value of 89.577, 100.440 and 3.287, respectively. These results showed that the non-coding region of BBTV-ZZ DNA 4 has a promoter activity not only in the virus replication in monocot, but also in driving the expression of a foreign gene in dicot plants.展开更多
The application of a new fluorogenic probe-based PCR assay (PCR duplex scorpion primer assay) to the detection of Hepatitis B virus (HBV) DNA in human sera was described. Duplex scorpion primer is a modified variant o...The application of a new fluorogenic probe-based PCR assay (PCR duplex scorpion primer assay) to the detection of Hepatitis B virus (HBV) DNA in human sera was described. Duplex scorpion primer is a modified variant of duplex Amplifluor, and the incorporation of a PCR stopper between probe and primer sequences improve the detection specificity and sensitivity. Combined with PCR amplification, this probe can give unambiguous positive results for the reactions initiated with more than 20 HBV molecules. In addition, the particular unimolecular probing mechanism of this probe makes the use of short target-specific probe sequence possible, which will render this probe applicable in some specific systems.展开更多
A new method based on the incorporation of a single-labelled probeprimer into polymerase chain reaction (PCR) for the detection of MR-amplified DNA in a closed system is reported. The probeprimer consists of a specifi...A new method based on the incorporation of a single-labelled probeprimer into polymerase chain reaction (PCR) for the detection of MR-amplified DNA in a closed system is reported. The probeprimer consists of a specific probe sequence on the 5'-end and a primer sequence on the 3'-end. A fluorophore is located at the 5'-end. The primer-quencher is an oligonucleotide, which is complementary to the probe sequence of probe-primer and labelled with,a quencher at the 3'-end. In the duplex formed by probe-primer and primer-quencher, the fluorophore and quencher am kept in close proximity to each other. Therefore the fluorescence is quenched. During PCR amplification, the specific probe sequence of probeprimer binds to its complement within the same strand of DNA, and is cleaved by Taq DNA polymerase, resulting in the restoration of fluorescence. This system has the same energy transfer mechanism as molecular beacons, and a good quenching efficiency can be ensured. Following optimization of PCR conditions, this method was used to detect hepatitis B virus (HBV) DNA in patient sera. This technology eliminates the risk of carry-over contamination, simplifies the amplification may and opens up new possibilities for the real-time detection of the amplified DNA.展开更多
AIM: To characterize the immunogenicity of a hepatitis C virus (HCV) E2 DNA vaccine alone or with a protein vaccine boost in murine and porcine animal models. METHODS: A DNA vaccine expressing a secreted form of H...AIM: To characterize the immunogenicity of a hepatitis C virus (HCV) E2 DNA vaccine alone or with a protein vaccine boost in murine and porcine animal models. METHODS: A DNA vaccine expressing a secreted form of HCV E2 protein was constructed and used to vaccinate mice and piglets with or without boosting with a recombinant E2 protein vaccine formulated with CpG ODN and 10% Emulsigen. The immunogenicity of HCV E2 vaccines was analyzed by ELISA for antibody responses, MTT assay for lymphocyte proliferation, ELISPOT for the number of interferon-γ secreting cells, and cytotoxic T lymphocyte assays. RESULTS: Intradermal injection of E2 DNA vaccine induced strong Th1-1ike immune responses in mice. In piglets, E2 DNA vaccine elicited moderate and more balanced immune responses. A DNA vaccine prime and protein boost vaccination strategy induced significantly higher E2-specific antibody levels and shifted the immune response towards Th2-1ike ones in piglets. CONCLUSION: A DNA vaccine expressing a secreted form of HCV E2 protein elicited E2-specific immune responses in mice and piglets. Recombinant E2 protein vaccination following DNA immunization significantly increased the antibody response in piglets. These HCV E2 vaccines may represent promising hepatitis C vaccine candidates for further investigations.展开更多
AIM: To investigate whether DNA vaccine encoding herpes simplex virus 1(HSV-1) glycoprotein C(g C) and glycoprotein D(g D) will achieve better protective effect against herpes simplex keratitis(HSK) than DNA ...AIM: To investigate whether DNA vaccine encoding herpes simplex virus 1(HSV-1) glycoprotein C(g C) and glycoprotein D(g D) will achieve better protective effect against herpes simplex keratitis(HSK) than DNA vaccine encoding gD alone. METHODS: DNA vaccine expressing gD or gC combined g D(g D.g C) were constructed and carried by chitosan nanoparticle. The expression of fusion protein gD and gC were detected in DNA/nanoparticle transfected 293 T cells by Western-blot. For immunization, mice were inoculated with DNA/nanoparticle for 3 times with 2 wk interval, and two weeks after the final immunization, the specific immune responses and clinical degrees of primary HSK were evaluated. RESULTS: Fusion protein g D.g C could be expressed successfully in cultured 293 T cells. And, p RSC-g C.g DIL21 DNA/chitosan nanoparticle could effectively elicit strongest humoral and cellular immune response in primary HSK mice evidenced by higher levels of specific neutralizing antibody and s Ig A production, enhanced cytotoxicities of splenocytes and nature killer cells(NK),when compared with those of gD alone or mocked vaccine immunized mice. As a result, gC-based vaccine immunized mice showed least HSK disease. CONCLUSION: gC-based DNA vaccine could effectively prevent the progress of primary HSK, suggesting that this DNA vaccine could be a promising vaccine for HSK treatment in the future.展开更多
Objective: This study aimed to comprehensively assess Epstein-Barr virus(EBV)-induced methylation alterations of B cell across whole genome.Methods: We compared DNA methylation patterns of primary B cells and corr...Objective: This study aimed to comprehensively assess Epstein-Barr virus(EBV)-induced methylation alterations of B cell across whole genome.Methods: We compared DNA methylation patterns of primary B cells and corresponding lymphoblastoid cell lines(LCLs) from eight participants. The genome-wide DNA methylation profiles were compared at over 850,000 genome-wide methylation sites.Results: DNA methylation analysis revealed 87,732 differentially methylated Cp G sites, representing approximately 12.41% of all sites in LCLs compared to primary B cells. The hypermethylated and hypomethylated Cp G sites were about 22.75% or 77.25%, respectively. Only 0.8% of hypomethylated sites and 4.5% of hypermethylated sites were located in Cp G islands, whereas 8.0% of hypomethylated sites and 16.3% of hypermethylated sites were located in shore(N_shore and S_shore). Using principal component analysis of the DNA methylation profiles, primary B cells and LCLs could be accurately predicted. Gene Ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) analysis of differently methylated genes revealed that most of the top GO biological processes were related to cell activation and immune response, and some top enrichment pathways were related with activation and malignant transformation of human B cells.Conclusions: Our study demonstrated genome-wide DNA methylation variations between primary B cells and corresponding LCLs, which might yield new insight on the methylation mechanism of EBV-induced immortalization.展开更多
A short note based on the homogeneous 5D space-time topological mappings is extended to cover DNAs of viruses and how the body’s immune system can be enhanced to recognize and remove it.
[ Objective] This study aimed to establish a simultaneous detection method of shrimp viruses by real-time fluorescence quantitative RT-PCR, to improve the efficiency of inspection and quarantine. [ Method] A novel rea...[ Objective] This study aimed to establish a simultaneous detection method of shrimp viruses by real-time fluorescence quantitative RT-PCR, to improve the efficiency of inspection and quarantine. [ Method] A novel real-time fluorescence quantitative RT-PCR assay was established and optimized for simultaneously detecting DNA/RNA of four shrimp viruses (WSSV, IHHNV, TSV and YHV ). [ Result] The optimized real-time fluorescence quantitative RT-PCR system gener- ated typical amplification curves with high amplification efficiencies (E = 1.06, 1.07, 0.92 and 0.92, respectively), good hnear relationship ( r = 1 ), uniform repeatability ( standard deviation = 0.05 - 0.46 ; variation coefficient = 0.26% - 1.62% ) and high sensitivity, exhibiting no significant differences compared with re- al-time fluorescence quantitative PCR (average error of Ct value = 0.04 -0.40; T = 0.53 -2.50; P 〉 0.05 ). The total detection time was about 1 h. [ Conclusion] The optimized real-time fluorescence quantitative RT-PCR system can be used for rapid detection of WSSV, IHHNV, TSV and YHV.展开更多
Large DNA viruses normally have complex structures with many of protein components derived from both viral and host origins. The development in proteomics, especially mass spectrometry identification techniques provid...Large DNA viruses normally have complex structures with many of protein components derived from both viral and host origins. The development in proteomics, especially mass spectrometry identification techniques provide powerful tools for analyzing large viruses. In this review, we have summarized the recent achievements on proteomic studies of large DNA viruses, such as herpesvirus, poxvirus, nimavirus and baculoviruse. The proteomics of baculovirus occlusion-derived virions (ODV) were emphasized. Different mass spectrometry techniques used on various baculoviruses were introduced, and the identified structurally associated proteins of baculoviruses are summarized.展开更多
文摘AIM: To study the relationship between hepatitis B virus (HBV) DNA levels and liver histology in patients with chronic hepatitis B (CHB) and to determine the prevalence and characteristics of hepatitis B e antigen (HBeAg) negative patients.METHODS: A total of 213 patients with CHB were studied, and serum HBV DNA levels were measured by the COBAS Amplicor HBV Monitor test. All patients were divided into two groups according to the HBeAg status.The correlation between serum HBV DNA levels and liver damage (liver histology and biochemistry) was explored.RESULTS: Of the 213 patients with serum HBV DNA levels higher than 10^5 copies/mL, 178 (83.6%) were HBeAg positive, 35 (16.4%) were HBeAg negative. The serum HBV DNA levels were not correlated to the age,history of CHB, histological grade and stage of liver disease in either HBeAg negative or HBeAg positive patients. There was no correlation between serum levels of HBV DNA and alanine aminotransferanse (ALT),aspartate aminotrans-ferase (AST) in HBeAg positive patients. In HBeAg negative patients, there was no correlation between serum levels of HBV DNA and AST,while serum DNA levels correlated with ALT (r = 0.351, P = 0.042). The grade (G) of liver disease correlated with ALT and AST (P 〈 0.05, r = 0.205, 0.327 respectively)in HBeAg positive patients. In HBeAg negative patients,correlations were shown between ALT, AST and the G (P 〈 0.01, and r = 0.862, 0.802 respectively). HBeAg negative patients were older (35 ± 9 years vs 30 ±9 years, P 〈 0.05 ) and had a longer history of HBV infection (8 ± 4 years vs 6 ± 4 years, P 〈 0.05) and a lower HBV DNA level than HBeAg positive patients (8.4± 1.7 Log HBV DNA vs 9.8 ± 1.3 Log HBV DNA, P 〈0.001). There were no significant differences in sex ratio,ALT and AST levels and liver histology between the two groups.CONCLUSION: Serum HBV DNA level is not correlated to histological grade or stage of liver disease in CHB patients with HBV DNA more than 10^5 copies/mL.Compared to HBeAg positive patients, HBeAg negative patients are older and have a lower HBV DNA level and a longer HBV infection history. There is no significant difference in sex ratio, ALT and AST levels and liver histology between the two groups.
文摘Hepatitis B is a major health concern in the Asia-Pacific region, and is endemic in China, Southeast Asia, and Africa. Chronic hepatitis B virus (HBV) infection may cause hepatic cirrhosis and liver cancer. It is estimated that there are more than 350 million chronic HBV carriers worldwide, of whom approximately one quarter will die of chronic hepatitis B-related liver diseases. HBV is transmitted horizontally through blood and blood products or by sexual transmission, and vertically from mother to infant. Perinatal infection is the predominant mode of transmission in countries with a high prevalence of hepatitis B surface antigen (HBsAg) carriage, and perinatal transmission leads to high rates of chronic infection. Therefore, it is important to prevent the mother-to-child transmission (MTCT) of HBV. Research has shown that pregnant women with high HBV DNA levels have an increased risk of MTCT. However, most of the obstetrics guidelines do not make a distinction between pregnant women with high HBV DNA levels and those who are HBsAg positive only. This review addresses the management of pregnant women with high levels of HBV viremia, in terms of antiviral therapy, use of hepatitis B immunoglobulin (HBIG), the combined application of hepatitis B vaccine and HBIG, choice of delivery mode and feeding practices. (C) 2014 Baishideng Publishing Group Inc. All rights reserved.
文摘AIM:To investigate the peripheral T-lymphocyte subpopulation profile,and its correlations with hepatitis B virus(HBV) replication level in chronic HBV-infected(CHI) individuals with normal liver function tests(LFTs) . METHODS:Frequencies of T-lymphocyte subpopu-lations in peripheral blood were measured by flow cytometry in 216 CHI individuals. HBV markers were detected with ELISA. Serum HBV DNA load was assessed with quantitative real-time PCR. Information of age at HBV infection,and maternal HBV infection status was collected. ANOVA linear trend test and linear regression were used in statistical analysis. RESULTS:CHI individuals had significantly decreased relative frequencies of CD3+,CD4+ subpopulationsand CD4+/CD8+ ratio,and increased CD8+ subset percentage compared with uninfected individuals(all P < 0.001) . There was a significant linear relationship between the load of HBV DNA and the parameters of T-lymphocyte subpopulations(ANOVA linear trend test P < 0.01) . The parameters were also significantly worse among individuals whose mothers were known to be HBV carriers,and those having gained infection before the age of 8 years. In multiple regressions,after adjustment for age at HBV infection and status of maternal HBV infection,log copies of HBV DNA maintained its highly significant predictive coefficient on T-lymphocyte subpopulations,whereas the effect of HBeAg was not significant. CONCLUSION:HBV DNA correlates with modification in the relative T-lymphocyte subpopulation frequencies. High viral load is more powerful than HBeAg in predicting the impaired balance of T-cell subsets.
基金Supported by Zhejiang Provincial Basic and Public Welfare Foundation,No.LGF22H030002Ningbo Science and Technology Program,No.2021S182+1 种基金Major Medical Scientific Research Foundation of National Health Commission of the People's Republic of China-Zhejiang Province,No.WKJ-ZJ-2341Zhejiang Province and Ningbo City Coconstructed Project of Leading Medical&Health Discipline,No.2016-S04.
文摘BACKGROUND Chronic hepatitis B virus(HBV)infection remains a major global public health problem.Chronic hepatitis B(CHB)patients can be divided into treatment indication and non-treatment indication individuals according to alanine transaminase(ALT),HBV DNA,serum hepatitis B e antigen status,disease status[liver cirrhosis,hepatocellular carcinoma(HCC),or liver failure],liver necroinflammation or fibrosis,patients’age,and family history of HCC or cirrhosis.For example,normal ALT patients in‘immune-tolerant’phase with HBV DNA higher than 10^(7)or 2×10^(7)IU/mL,and those in‘inactive-carrier’phase with HBV DNA lower than 2×10^(3)IU/mL do not require antiviral therapy.However,is it reasonable to set the defined values of HBV DNA as the fundamental basis to estimate the disease state and to determine whether to start treatment?In fact,we should pay more attention to those who do not match the treatment indications(grayzone patients both in the indeterminate phase and in the‘inactive-carrier’phase).AIM To analyze the correlation of HBV DNA level and liver histopathological severity,and to explore the significance of HBV DNA for CHB with normal ALT.METHODS From January 2017 to December 2021,a retrospective cross-sectional set of 1299 patients with chronic HBV infection(HBV DNA>30 IU/mL)who underwent liver biopsy from four hospitals,including 634 with ALT less than 40 U/L.None of the patients had received anti-HBV treatment.The degrees of liver necroinflammatory activity and liver fibrosis were evaluated according to the Metavir system.On the basis of the HBV DNA level,patients were divided into two groups:Low/moderate replication group,HBV DNA≤10^(7)IU/mL[7.00 Log IU/mL,the European Association for the Study of the Liver(EASL)guidelines]or≤2×10^(7)IU/mL[7.30 Log IU/mL,the Chinese Medical Association(CMA)guidelines];high replication group,HBV DNA>10^(7)IU/mL or>2×10^(7)IU/mL.Relevant factors(demographic characteristics,laboratory parameters and noninvasive models)for liver histopathological severity were analyzed by univariate analysis,logistics analysis and propensity score-matched analysis.RESULTS At entry,there were 21.45%,24.29%,and 30.28%of the patients had liver histopathological severities with≥A2,≥F2,and≥A2 or/and≥F2,respectively.HBV DNA level(negative correlation)and noninvasive model liver fibrosis 5 value(positive correlation)were independent risk factors for liver histopathological severities(liver necroinflammation,liver fibrosis,and treatment indication).The AUROCs of the prediction probabilities(PRE_)of the models mentioned above(<A2 vs≥A2,<F2 vs≥F2,<A2 and<F2 vs≥A2 or/and≥F2)were 0.814(95%CI:0.770-0.859),0.824(95%CI:0.785-0.863),and 0.799(95%CI:0.760-0.838),respectively.HBV DNA level(negative correlation)was still an independent risk factor when diagnostic models were excluded,the P values(<A2 vs≥A2,<F2 vs≥F2,<A2 and<F2 vs≥A2 or/and≥F2)were 0.011,0.000,and 0.000,respectively.For the propensity score-matched pairs,whether based on EASL guidelines or CMA guidelines,the group with significant liver histology damage(≥A2 or/and≥F2)showed much lower HBV DNA level than the group with non-significant liver histology damage(<A2 and<F2).Patients in the moderate replication group(with indeterminate phase)had the most serious liver disease pathologically and hematologically,followed by patients in the low replication group(with‘inactive-carrier’phase)and then the high replication group(with‘immune-tolerant’phase).CONCLUSION HBV DNA level is a negative risk factor for liver disease progression.The phase definition of CHB may be revised by whether the level of HBV DNA exceeds the detection low limit value.Patients who are in the indeterminate phase or‘inactive carriers’should receive antiviral therapy.
文摘AIM To investigate and compare the analytical and clinical performance of Tian Long automatic hypersensitive hepatitis B virus(HBV) DNA quantification system and Roche CAP/CTM system.METHODS Two hundred blood samples for HBV DNA testing, HBV-DNA negative samples and high-titer HBV-DNA mixture samples were collected and prepared. National standard materials for serum HBV and a worldwide HBV DNA panel were employed for performance verification. The analytical performance, such as limit of detection, limit of quantification, accuracy, precision, reproducibility, linearity, genotype coverage and cross-contamination, was determined using the Tian Long automatic hypersensitive HBV DNA quantification system(TL system). Correlation and Bland-Altman plot analyses were carried out to compare the clinical performance of the TL system assay and the CAP/CTM system. RESULTS The detection limit of the TL system was 10 IU/m L, and its limit of quantification was 30 IU/m L. The differences between the expected and tested concentrations of the national standards were less than ± 0.4 Log10 IU/m L, which showed high accuracy of the system. Results of the precision, reproducibility and linearity tests showed that the multiple test coefficient of variation(CV) of the same sample was less than 5% for 102-106 IU/m L; and for 30-108 IU/m L, the linear correlation coefficient r2 = 0.99. The TL system detected HBV DNA(A-H) genotypes and there was no cross-contamination during the "checkerboard" test. When compared with the CAP/CTM assay, the two assays showed 100% consistency in both negative and positive sample results(15 negative samples and 185 positive samples). No statistical differences between the two assays in the HBV DNA quantification values were observed(P > 0.05). Correlation analysis indicated a significant correlation between the two assays, r2 = 0.9774. The Bland-Altman plot analysis showed that 98.9% of the positive data were within the 95% acceptable range, and the maximum difference was-0.49.CONCLUSION The TL system has good analytical performance, and exhibits good agreement with the CAP/CTM system in clinical performance.
基金supported by grants from the National Key Research and Development Program of China(Grant No.2016YFC0902001)the Sino-Sweden Joint Research Program(Grant No.81861138006)+5 种基金the Science and Technology Planning Project of Guangzhou,China(Grant No.201804020094)the National Natural Science Foundation of China(Grant Nos.81973131,81903395,81803319,and 81502056)the National Science Fund for Distinguished Young Scholars of China(Grant No.81325018)the Key Project for International Cooperation and Exchange of the National Natural Science Foundation of China(Grant No.81220108022)the Natural Science Foundation of Guangdong Province(Grant No.2017A030312003)。
文摘Objective:Circulating cell-free Epstein-Barr virus(EBV)DNA has been shown to be a valuable biomarker for population screening and prognostic surveillance for nasopharyngeal carcinoma(NPC).Despite important insights into the biology of persistence,few studies have addressed the clinical significance of cell-based EBV-DNA loads in peripheral blood cells(PBCs).Methods:A prospective observational cohort study was conducted involving 1,063 newly diagnosed,locoregionally-advanced NPC patients at Sun Yat-sen University Cancer Center from 2005 to 2007.Cox regression analysis was conducted to identify the association of PBC EBV DNA loads to overall survival(OS)and other prognostic outcomes.Prognostic nomograms were developed based on PBC EBV DNA loads to predict survival outcomes for NPC patients.Results:After a median follow-up of 108 months,patients with higher PBC EBV-DNA loads had significantly worse OS[hazard ratio(HR)of medium,medium-high,and high vs.low were 1.50,1.52,and 1.85 respectively;Ptrend<0.001].Similar results were found for progression-free survival and distant metastasis-free survival.The concordance index of the prognostic nomogram for predicting OS in the training set and validation set were 0.70 and 0.66,respectively.Our data showed that the PBC EBV DNA load was an independent and robust survival biomarker,which remained significant even after adjusting for plasma EBV DNA loads in a subset of 205 patients of the cohort(HR:1.88;P=0.025).Importantly,a combination of PBC EBV DNA load and plasma EBV DNA load improved the predicted OS.Conclusions:The EBV-DNA load in PBCs may be an independent prognosis marker for NPC patients.
文摘Duck hepatitis B vims (DHBV) DNA was detected in different tumorous nodules of ducks with hepatic multicentric cancer or intrahepatic metastasis by Southern blot technique. Among 7 ducks with hepatocellular carcinoma of multiple tumor nodules, the hybridization pattern of Integrated DHBV DNA In different tumorous nodules was identical in 3 cases and different in 2 cases. One case showed a similar hybridization pattern in two tumorous nodules and other one was negative tor DHBV DNA. Integrated DHBV DNA was also identified in a metastatic lung cancer of ducks with hepatocellular carcinoma. The hybridization pattern of metastasis of lungs was as the some as that in primary hepatocellular carcinoma. The same discrete hybridization bands In the different tumorous nodules indicate that these nodules might arise from one transformed cell. The different hybridization patterns In various tumorous nodules show that these tumorous nodules might arise from various transformed cells. The results suggest that the hybridization pattern of different nodules of hepatocellular carcinoma with viral DNA probe could make a cell clone origin marker of tumor nodule to differentiate hepatic multlcentric cancer from Intrahepatic metastatic cancer.
文摘Objective:To investigate the disparities and associations between HBV DNA and HBV RNA in various liver disease groups with respect to HBeAg status.Methods:Between September 2020 and September 2023,90 patients diagnosed with chronic hepatitis B(CHB),74 patients diagnosed with liver cirrhosis(LC),and 102 patients diagnosed with hepatocellular carcinoma(HCC)from the Department of Gastroenterology or Infection at the First Affiliated Hospital of Xi’an Jiaotong University were selected.HBV DNA,HBV RNA,and HBeAg quantitative tests were conducted using serum samples from the same patients.Results:In the three groups of cases,the HBV RNA load was higher when HBeAg was positive than when HBeAg was negative,and this difference was statistically significant.Only in the HCC group was the HBV DNA load significantly higher when HBeAg was positive than when HBeAg was negative.Additionally,there was a positive correlation between HBV DNA and HBV RNA regardless of HBeAg status.Conclusion:During HBeAg conversion,HBV RNA demonstrates a more sensitive response than HBV DNA.As CHB progresses to LC or HCC,HBV RNA exhibits better diagnostic value than HBV DNA.
文摘AIM: To clarify the effect of SEN virus (SENV) infection on a combination therapy including interferon alfa (IFN-α) or pegylated-IFN with ribavirin in patients with chronic hepatitis and the effect of a combination therapy on SENV.METHODS: SENV DNA was determined by polymerase chain reaction in serum samples from 95 patients with chronic hepatitis C. Quantitative analysis was done for SENV H DNA.RESULTS: Twenty-one (22%) of 95 patients were positive for SENV DNA. There was no difference in clinical and biochemical parameters between patients with HCV infection alone and coinfected patients. The sustained response rate for HCV clearance after combination therapy did not differ between patients with SENV (52%) and without SENV(50%, n.s.). SENV DNA was undetectable in 76% of the initially SENV positive patients at the end of follow-up. SENV H response to combination therapy was significantly correlated with SENV DNA level (P=-0.05).CONCLUSION: SENV infection had no influence on the HCV sustained response rate to the combination therapy.Response rate of SENV to the combination therapy depends on SENV DNA level.
基金sponsored by Hangzhou Medical Health Science and Technology Project[No.A20220558]the Special Supporting Program of Agriculture and Social Development from Hangzhou Municipal Science&Technology Bureau[No.202203B34].
文摘Objective This study aimed to investigate the prevalence of Epstein-Barr virus(EBV)infection in patients with and without cancer.Methods A total of 26,648 participants who underwent whole-blood EBV DNA(WBEBV)assays between January 1,2020,and August 31,2023,were included.The chi-square test was used for categorical data analysis,and R software was used to analyze the differences in EBV DNA load levels and the diagnostic capabilities of WBEBV.Results Positive rates were 10.2%and 25.4%for healthy controls(HC)and patients,respectively.The positivity rate for EBV-associated neoplasms(EN)was the highest at 7.53%,followed by leukemia(Le)at 5.49%.The subgroup analysis showed that the positivity rate for abnormal proliferation or hyperplasia(APH)was 31.9%,followed by 30.5%for Le.The WBEBV of patients with transplants(TP),especially living-related transplants(LT),was the highest among all subgroups.WBEBV at diagnosis was used to differentiate between infectious mononucleosis(IM)and chronic active Epstein-Barr virus(CAEBV),with a sensitivity of 67.4%(95%confidence interval[CI]:57.6-75.8)and specificity of 72%(95%CI:63.3-79.3).We conclude that the prevalence of EBV infection is low in the healthy population in this region and that a high EBV load at baseline is more common in LT,IM,and Lymphocyte Leukemia(LL).Conclusion This study used a large-sample survey to characterize the prevalence of whole-blood EBV levels in various diseases,including the stages and subtypes.The EBV detection rate was higher in patients with malignant disease than in those with benign disease.Our study provides clinicians with baseline information regarding EBV-associated diseases.
文摘AIM To explore a rapid and easy sequencing method for hepatitis C virus (HCV) genome, and establish a new sequencing method in China. METHODS Polymerase Chain Reaction (PCR) was combined with DNA sequencing technique. PCR products were purified by agarose gel electrophoresis, polyacrylamide gel electrophoresis (PAGE), Polyethylene glycol (PEG) respectively. Then in the presence of a 5′ labeling PCR primer, purified PCR products were directly sequenced. By this method, HCV NS5b cDNA from two HCV infected individuals (HC 42 and HC 49) were sequenced.
文摘Banana bunchy top virus Chinese Zhangzhou isolate (BBTV-ZZ) DNA 4 was amplified by PCR and cloned. Sequence analysis showed that BBTV-ZZ DNA 4 is 1 039 nucleotides (nts) in length and this virus could be one member of BBTV Asian group. Transcriptional initiation site A, which is at the 269 nucleotide, was preliminarily determined by using 5' RACE method. BBTV-ZZ DNA 4 non-coding region was sub-cloned by PCR and inserted into upstream of gfp : : gus plant expression vector pCAMBIA 1304 to construct recombinant plasmid pTA2. Agrobacterium tumefaciens harboring pTA2 was injected into leaves of the tobacco (Nicotiana tabacum L. cv. Xanthi NC) via Agrobacterium-infiltration procedure. Transient expressions of GUS and GFP were determined in injected leaves 3 - 5 d later. GUS activities of pTA2, pCAMBIA 1304 injected and non-injected tobacco leaves respectively were 1.007 0 pmol MU(.)mug(-1.)min(-1), 2.069 0 pmol MU(.)mug(-1.)min(-1) and 0.021 4 pmol MU(.)mug(-1.)min(-1). Indirect ELISA for GFP in 1 mg total protein from pTA2, pCAMBIA 1304 injected and non-injected leaves showed an A(490 nm) value of 89.577, 100.440 and 3.287, respectively. These results showed that the non-coding region of BBTV-ZZ DNA 4 has a promoter activity not only in the virus replication in monocot, but also in driving the expression of a foreign gene in dicot plants.
基金the National Natural Science Foundation of China (No. 20075012) and the Outstanding Scholar Program of Nankai University.
文摘The application of a new fluorogenic probe-based PCR assay (PCR duplex scorpion primer assay) to the detection of Hepatitis B virus (HBV) DNA in human sera was described. Duplex scorpion primer is a modified variant of duplex Amplifluor, and the incorporation of a PCR stopper between probe and primer sequences improve the detection specificity and sensitivity. Combined with PCR amplification, this probe can give unambiguous positive results for the reactions initiated with more than 20 HBV molecules. In addition, the particular unimolecular probing mechanism of this probe makes the use of short target-specific probe sequence possible, which will render this probe applicable in some specific systems.
基金ProjectsupportedbytheNationalNaturalScienceFoundationofChina (No .2 0 0 75 0 12 )
文摘A new method based on the incorporation of a single-labelled probeprimer into polymerase chain reaction (PCR) for the detection of MR-amplified DNA in a closed system is reported. The probeprimer consists of a specific probe sequence on the 5'-end and a primer sequence on the 3'-end. A fluorophore is located at the 5'-end. The primer-quencher is an oligonucleotide, which is complementary to the probe sequence of probe-primer and labelled with,a quencher at the 3'-end. In the duplex formed by probe-primer and primer-quencher, the fluorophore and quencher am kept in close proximity to each other. Therefore the fluorescence is quenched. During PCR amplification, the specific probe sequence of probeprimer binds to its complement within the same strand of DNA, and is cleaved by Taq DNA polymerase, resulting in the restoration of fluorescence. This system has the same energy transfer mechanism as molecular beacons, and a good quenching efficiency can be ensured. Following optimization of PCR conditions, this method was used to detect hepatitis B virus (HBV) DNA in patient sera. This technology eliminates the risk of carry-over contamination, simplifies the amplification may and opens up new possibilities for the real-time detection of the amplified DNA.
基金Supported by the Canadian Network for Vaccines and Immuno-therapeutics
文摘AIM: To characterize the immunogenicity of a hepatitis C virus (HCV) E2 DNA vaccine alone or with a protein vaccine boost in murine and porcine animal models. METHODS: A DNA vaccine expressing a secreted form of HCV E2 protein was constructed and used to vaccinate mice and piglets with or without boosting with a recombinant E2 protein vaccine formulated with CpG ODN and 10% Emulsigen. The immunogenicity of HCV E2 vaccines was analyzed by ELISA for antibody responses, MTT assay for lymphocyte proliferation, ELISPOT for the number of interferon-γ secreting cells, and cytotoxic T lymphocyte assays. RESULTS: Intradermal injection of E2 DNA vaccine induced strong Th1-1ike immune responses in mice. In piglets, E2 DNA vaccine elicited moderate and more balanced immune responses. A DNA vaccine prime and protein boost vaccination strategy induced significantly higher E2-specific antibody levels and shifted the immune response towards Th2-1ike ones in piglets. CONCLUSION: A DNA vaccine expressing a secreted form of HCV E2 protein elicited E2-specific immune responses in mice and piglets. Recombinant E2 protein vaccination following DNA immunization significantly increased the antibody response in piglets. These HCV E2 vaccines may represent promising hepatitis C vaccine candidates for further investigations.
基金Supported by Natural Science Foundation of Jiangsu Province (No.BK20141346)Nanjing Science and Technology Development Plan (No.201402001)
文摘AIM: To investigate whether DNA vaccine encoding herpes simplex virus 1(HSV-1) glycoprotein C(g C) and glycoprotein D(g D) will achieve better protective effect against herpes simplex keratitis(HSK) than DNA vaccine encoding gD alone. METHODS: DNA vaccine expressing gD or gC combined g D(g D.g C) were constructed and carried by chitosan nanoparticle. The expression of fusion protein gD and gC were detected in DNA/nanoparticle transfected 293 T cells by Western-blot. For immunization, mice were inoculated with DNA/nanoparticle for 3 times with 2 wk interval, and two weeks after the final immunization, the specific immune responses and clinical degrees of primary HSK were evaluated. RESULTS: Fusion protein g D.g C could be expressed successfully in cultured 293 T cells. And, p RSC-g C.g DIL21 DNA/chitosan nanoparticle could effectively elicit strongest humoral and cellular immune response in primary HSK mice evidenced by higher levels of specific neutralizing antibody and s Ig A production, enhanced cytotoxicities of splenocytes and nature killer cells(NK),when compared with those of gD alone or mocked vaccine immunized mice. As a result, gC-based vaccine immunized mice showed least HSK disease. CONCLUSION: gC-based DNA vaccine could effectively prevent the progress of primary HSK, suggesting that this DNA vaccine could be a promising vaccine for HSK treatment in the future.
基金supported by grants from National Natural Science Foundation of China (No. 81160249, 81301886 and 81760525)Science Foundation of Peking University Cancer Hospital (No. 2017 Zizhu-1)+4 种基金Open Project funded by Key Laboratory of Carcinogenesis and Translational ResearchMinistry of Education/Beijing (2017 Open Project-3)Beijing Municipal Science & Technology Commission (No. Z171100001017136)Beijing Natural Science Foundation (No. 7171001)West China First-Class Discipline Construction Project in Basic Medicine funded by Ningxia Medical University
文摘Objective: This study aimed to comprehensively assess Epstein-Barr virus(EBV)-induced methylation alterations of B cell across whole genome.Methods: We compared DNA methylation patterns of primary B cells and corresponding lymphoblastoid cell lines(LCLs) from eight participants. The genome-wide DNA methylation profiles were compared at over 850,000 genome-wide methylation sites.Results: DNA methylation analysis revealed 87,732 differentially methylated Cp G sites, representing approximately 12.41% of all sites in LCLs compared to primary B cells. The hypermethylated and hypomethylated Cp G sites were about 22.75% or 77.25%, respectively. Only 0.8% of hypomethylated sites and 4.5% of hypermethylated sites were located in Cp G islands, whereas 8.0% of hypomethylated sites and 16.3% of hypermethylated sites were located in shore(N_shore and S_shore). Using principal component analysis of the DNA methylation profiles, primary B cells and LCLs could be accurately predicted. Gene Ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) analysis of differently methylated genes revealed that most of the top GO biological processes were related to cell activation and immune response, and some top enrichment pathways were related with activation and malignant transformation of human B cells.Conclusions: Our study demonstrated genome-wide DNA methylation variations between primary B cells and corresponding LCLs, which might yield new insight on the methylation mechanism of EBV-induced immortalization.
文摘A short note based on the homogeneous 5D space-time topological mappings is extended to cover DNAs of viruses and how the body’s immune system can be enhanced to recognize and remove it.
文摘[ Objective] This study aimed to establish a simultaneous detection method of shrimp viruses by real-time fluorescence quantitative RT-PCR, to improve the efficiency of inspection and quarantine. [ Method] A novel real-time fluorescence quantitative RT-PCR assay was established and optimized for simultaneously detecting DNA/RNA of four shrimp viruses (WSSV, IHHNV, TSV and YHV ). [ Result] The optimized real-time fluorescence quantitative RT-PCR system gener- ated typical amplification curves with high amplification efficiencies (E = 1.06, 1.07, 0.92 and 0.92, respectively), good hnear relationship ( r = 1 ), uniform repeatability ( standard deviation = 0.05 - 0.46 ; variation coefficient = 0.26% - 1.62% ) and high sensitivity, exhibiting no significant differences compared with re- al-time fluorescence quantitative PCR (average error of Ct value = 0.04 -0.40; T = 0.53 -2.50; P 〉 0.05 ). The total detection time was about 1 h. [ Conclusion] The optimized real-time fluorescence quantitative RT-PCR system can be used for rapid detection of WSSV, IHHNV, TSV and YHV.
基金The grants of National Science Foundation of China (30630002, 30670078)973 Program(2009CB118903)Programme Strategic Scientific Alliances between China and the Netherlands (2008AA000238)
文摘Large DNA viruses normally have complex structures with many of protein components derived from both viral and host origins. The development in proteomics, especially mass spectrometry identification techniques provide powerful tools for analyzing large viruses. In this review, we have summarized the recent achievements on proteomic studies of large DNA viruses, such as herpesvirus, poxvirus, nimavirus and baculoviruse. The proteomics of baculovirus occlusion-derived virions (ODV) were emphasized. Different mass spectrometry techniques used on various baculoviruses were introduced, and the identified structurally associated proteins of baculoviruses are summarized.