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【Objective】 To establish a magnetic bead enrichment strategy for the detection of human immunodeficiency virus deoxyribonucleic acid (HIV DNA) in peripheral blood, and to verify the improvement of the sensitivity of this method for the detection of HIV DNA in HIV infected patients after early antiretrovital treatment (ART). 【Methods】 Peripheral whole blood was collected at 4 timepoints in one ART HIV window period (WP) patient. Peripheral blood mononuclear cells (PBMCs) were isolated on a Ficoll gradient. CD4+ T lymphocytes were enriched from total PBMCs by negative sorting. HIV DNA concentration in magnetic beads enriched group and whole blood group was detected by HIV DNA detection kit. 【Results】 CD4+ T cells were isolated by magnetic beads and identified by FCM for purity at (96.4 ± 2.6)%. The viability was (95.9 ± 2.9)%, as demonstrated by trypan blue staining. The person on continued ART treatment in this study had significantly greater reduction in HIV viral load and undetectable HIV plasma RNA at follow up timepoint 4. No HIV DNA was detected in the whole blood group at all 4 timepoints. The quantitative results of HIV DNA in the CD4+ T lymphocyte group of the magnetic bead enrichment group were 73.4, 429.3, 137.1, 449.9 copies/106 CD4+ T cell′s respectively. 【Conclusion】 The magnetic bead enrichment method can be more sensitive in detecting the limit low copy HIV DNA in blood samples, and provide early confirmatory data for HIV WP infection and breakthrough infection after ART treatment.
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【Objective】 To analyze the SARS-CoV-2 detection results among blood donors in different periods of COVID-19 pandemic control in Shenzhen and assess the antibody levels and infection status of blood donors in different periods, so as to provide reference for subsequent blood testing strategies. 【Methods】 A total of 4 768 plasma samples of blood donors were subjected to pooled testing by nucleic acid testing(NAT) with 8 samples per pool. Additionally, these samples were subjected to a 1000-fold dilution, and the detection of SARS-CoV-2 total antibody was performed by enzyme-linked immunosorbent assay (ELISA). The 4 768 plasma samples were collected from blood donors at different time points in Shenzhen, with inquiries made to determine whether donors during the COVID-19 pandemic were in the convalescence. The antibody positive rates in blood screening samples during different periods of the pandemic and samples from individuals in the convalescence of COVID-19 infection were analyzed. Furthermore, the antibody levels were examined for differences based on gender, age, and blood type. 【Results】 All 4 768 plasma samples from blood donors were negative by NAT, while 2 342 samples were detected positive by the SARS-CoV-2 total antibody detection, with a positive rate of 49.1%. These samples from four periods (September 30 to October 3, 2022; November 3 to 6, 2022; December 27 to 31, 2022; January 6 to 18, 2023) were subjected to a 1 000-fold dilution for COVID-19 antibody detection, and the positive rates were 21.3%, 15.8%, 65.9%, and 93.9%, respectively. 【Conclusion】 The prevalence of COVID-19 antibodies among blood donors in Shenzhen during different periods of the pandemic varied significantly. There was no difference in antibody prevalence among different genders and blood types, while younger individuals exhibited a higher prevalence of antibodies. The risk of COVID-19 transmission through blood transfusion was found to be extremely low.
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【Objective】 To analyze the results of different methods for reactive samples screened by the enzyme linked immunosorbent assay (ELISA) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in blood donors. 【Methods】 From March to April 2020, a total of 8 632 blood samples in Shenzhen were screened for SARS-CoV-2 total antibodies (TAb, including IgG, IgM, IgA) in plasma using ELISA(PC group), the antibody reactivity samples and their follow up plasma samples (FC group), and samples of disease control group(DC group) from January to April 2020 were detected using the following methods: 1) ELISA method for detecting IgG, IgM, and (or without detection) TAb; 2) pseudovirus neutralizing antibody test(pVNT); 3) western blot (WB) of SARS-CoV-2 antibody. The negative control group(NC group) from February to April 2020 performed ELISA and WB testing. 【Results】 Among the 34 total antibody positive samples, 2 were positive for pVNT test, and the total antibody, IgG and WB in the initial screening and tracking testing were positive. Thereafter, it was determined to be confirmed positive. The other 2 cases were positive for pVNT test, while the samples with positive WB results were in the follow-up stage. The TAb, IgG, and pVNT results did not conform to the dynamic evolution of antibodies, and cannot be determined as confirmed positive. 【Conclusion】 The infection status of antibody reactivity samples screened by SARS-CoV-2 ELISA can be judged by the logic of pVNT, WB and the dynamic change of antibody.
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【Objective】 To evaluate the performance and clinical application of a high-throughput nucleic acid blood screening detection system for SARS-CoV-2, so as to provide basis and technical means for its application in detection of plasma from recovered COVID-19 patients. 【Methods】 The SARS-CoV-2 nucleic acid was detected by real-time fluorescence quantitative PCR, and the sensitivity, precision, anti-interference and other parameters were evaluated. Blood donor samples collected during COVID-19 epidemic period were screened using the detection system to evaluate its applicability. 【Results】 The detection limits of gene N and ORF 1ab were 3.98 copies/mL and 9.38 copies/mL, respectively. The CV of high and low concentration samples were both less than 5%. Hemoglobin at 500 mg/dL and triglyceride at 3g/dL had little effect on the results. The detection system can effectively prevent carryover, thus avoiding false positive results. The SARS-CoV-2 nucleic acid blood screening was carried out in a total of 39 306 blood samples, and all samples were negative. 【Conclusion】 The established method can meet the needs of SARS-CoV-2 nucleic acid screening therefore ensure the safe application of plasma from recovered COVID-19 patients.
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【Objective】 To assess three severe acute respiratorysyndrome coronavirus 2 (SARS-CoV-2) enzyme linked immunosorbent assays (ELISA) and one pseudotype lentivirus-based neutralization test (ppNAT) in detecting the convalescent plasma antibody levles from COVID-19. 【Methods】 30 COVID-19 convalescent plasma samples were screened for antibodies against SARS-CoV-2 using three kinds of SARS-CoV-2 ELISA reagents and one ppNAT test in Shenzhen. The controls consisted of plasma samples from 32 healthy blood donors in February 2019. The diagnostic efficacy analysis of various SARS-CoV-2 ELISA reagents was performed using real-time fluorescent Polymerase Chain Reaction (RT-PCR). We also analyzed correlation between different immunological reagents and the age, gender, hospitalization, and severity of illness. 【Results】 The positive yielding rate of ppNAT and three kinds of IgG ELISA was higher than that of IgM ELISA. The positive yielding rates of three kinds of IgG ELISA were 100%(30/30), 93.33%(28/30), and 96.67%(29/30) respectively, while the yielding rates in control group were all 0. The positive yielding rate of three IgM ELISAs were 93.33%(28/30), 70%(21/30)and 46.67% (14/30). All the cases from negative control group were negative for IgG and IgM. Pearson correlation coefficient was calculated; there was a strong correlation between ELISA reagent 2 IgG and ELISA reagent 3 IgG (r=0.765, P0.05). 【Conclusion】 In the convalescent plasma with nucleic acid confirmed covid-19, the yielding rates of different IgM antibodies varied greatly. Antibody levels were influenced by age to some extent.
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【Objective】 To analyze the viability of 2 different blood screening strategies against SARS-CoV-2 in low risk populations, so as to provide references for the formulation of blood screening strategy. 【Methods】 Two screening strategies for antibodies against SARS-CoV-2 were adopted: 1) the total antibody were initially screened for all samples, and the antibody IgG and IgM were retested in those primary positive samples; 2) only antibody test of IgG and IgM for all samples. And SARS-CoV-2 nucleic acid was detected in parallel. Reactive samples was confirmed by neutralization test. The sensitivity, specificity and true positive rate of two strategies were calculated. 【Results】 None was positive for SARS-CoV-2 nucleic acid among 880 samples. Four truly positive samples were implicated in 9 (1.02%, 9/880) initially reactive samples in total antibody test; 3 in 26 (2.95%, 26/880) initially IgG or IgM reactive samples. 【Conclusion】 The first strategy is superior to the second strategy in the sensitivity and specificity, and is recommended for the detection of SARS-CoV-2 antibody in low risk populations.
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【Objective】 To track and evaluate the clinical diagnostic efficacy of an enzyme linked immunosorbent assay (ELISA) kit for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). 【Methods】 Total antibody (TAb) specific to SARS-CoV-2 in blood donors were determined using ELISA reagent. TAb positive donors were followed up 1 month after blood donation. SARS-CoV-2 specific IgG, IgM and pseudotype lentivirus based neutralization test (ppNAT) were conducted for TAb positive blood donors and follow-up samples. ppNAT and IgG antibodies simultaneously positive in ppNAT positive samples and its follow-up samples was used as the standard for antibodies validation. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy and Youden index of SARS-CoV-2 TAb ELISA were analyzed. 【Results】 Among 16 016 blood donors from January 31 to April 28, 2020, 61 donors were diagnosed as TAb positive, 6 cases were positive for ppNAT, in which 2 were positive for both ppNAT and IgG; 4 of 46 TAb positive follow-up samples were positive for ppNAT, in which 2 were positive for IgG simultaneously. The sensitivity, specificity, PPV, NPV, accuracy, Youden index, false positive rate and false negative rate of SARS-CoV-2 TAb reagent were 100.00%, 99.60%, 3.28%, 100.00%, 99.60%, 99.60%, 0.40% and 0.00%, respectively. 【Conclusion】 SARS-CoV-2 TAb ELISA has high sensitivity and good clinical diagnostic efficacy, but the false positive rate is relatively high in low-risk blood donors. Therefore, ppNAT, IgG and follow-up results should be fully considered in clinical in order to analyze the positive results and determine the infection status more accurately.
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Objective To investigate the clinical features and prognosis factors of acquired immunodeficiency syndrome(AIDS)patients complicated with cryptococcal meningitis(CM).Methods Retrospective analyses were performed on clinical features,laboratory data,treatment status and related prognosis factors in 8 1 AIDS patients with CM admitted to the Department of Infectious Diseases,Beijing You'an Hospital,Capital Medical University from January 2010 to December 2017.The t test,rank sum test and x2 test were employed to analyze the data.Results of the 81 AIDS patients with CM,71 cases were infected with human immunodeficiency virus(HIV)by sexual transmission(87.7％).The most common clinical symptoms were fever in 60(74.1％),headache in 72(88.9％),and nausea and vomiting in 56(69.1％),Cerebrospinal fluid(CSF)examination results show that 60 cases(74.1％)had elevated opening pressure,the white blood cell count was 17.0(6.0,44.5)×106/L,monocyte count was 9.0(3.0,29.5)×106/L,the level of chloride was(117.26±5.61)mmol/L,of glucose was 2.89(2.05,3.41)mmol/L,of protein was 0.32(0.21,0.65)g/L,ink staining positive rate was 84.0％(68/81),fungal culture positive rate was 59.3％(48/81).The positive rate of serum cryptococcal antigen was 96.3％(78/81),and CSF cryptococcal antigen positive rate was 93.8％(76/81).The clinical efficacies were not significant different among different treatment regimens(x2=1.479,P=0.533).After treatment,60 patients survived and 21 died,with an overall mortality rate of 25.9％.Univariate analysis showed that consciousness disorder and CSF opening pressure were significantly higher in the death group than those in the survival group(x2=22.365,t=0.317,respectively,both P＜0.05),while serum albumin(Alb)and CD4+T lymphocyte counts were significantly lower in the death group than those in the survival group(t=7.975,Z=-3.073,respectively,both P＜0.05).Multivariate logistic regression analysis showed that consciousness disorder and Alb were independent factors influencing the clinical outcome of AIDS patients with CM.Consciousness disorder was related with poor outcome(odd ratio(OR)=26.704,P=0.011,95％confidence interval(CI)2.115-337.247),and higher Alb was related with good outcome(OR=0.671,P=0.005,95％CI0.507-0.888).The area under the receiver operating characteristic curve of serum Alb for predicting poor outcomes of AIDS patients with CM was 0.932(95％CI0.859-0.998,P＜0.01).By using 31.7 g/L as cut-off value,the sensitivity was 95％and the specificity was 8 1％for predicting poor outcome.Conclusions AIDS complicated with CM has a high mortality rate,and its clinical features are lack of specificity.Consciousness disorder and Alb are independent prognosis factors.
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Objective@#To investigate the clinical features and prognosis factors of acquired immunodeficiency syndrome (AIDS) patients complicated with cryptococcal meningitis (CM).@*Methods@#Retrospective analyses were performed on clinical features, laboratory data, treatment status and related prognosis factors in 81 AIDS patients with CM admitted to the Department of Infectious Diseases, Beijing You′an Hospital, Capital Medical University from January 2010 to December 2017. The t test, rank sum test and χ2 test were employed to analyze the data.@*Results@#Of the 81 AIDS patients with CM, 71 cases were infected with human immunodeficiency virus (HIV) by sexual transmission (87.7%). The most common clinical symptoms were fever in 60 (74.1%), headache in 72 (88.9%), and nausea and vomiting in 56 (69.1%). Cerebrospinal fluid (CSF) examination results show that 60 cases (74.1%) had elevated opening pressure, the white blood cell count was 17.0 (6.0, 44.5)×106/L, monocyte count was 9.0 (3.0, 29.5)×106/L, the level of chloride was (117.26±5.61) mmol/L, of glucose was 2.89 (2.05, 3.41) mmol/L, of protein was 0.32 (0.21, 0.65) g/L, ink staining positive rate was 84.0% (68/81), fungal culture positive rate was 59.3% (48/81). The positive rate of serum cryptococcal antigen was 96.3% (78/81), and CSF cryptococcal antigen positive rate was 93.8% (76/81). The clinical efficacies were not significant different among different treatment regimens (χ2=1.479, P=0.533). After treatment, 60 patients survived and 21 died, with an overall mortality rate of 25.9%. Univariate analysis showed that consciousness disorder and CSF opening pressure were significantly higher in the death group than those in the survival group (χ2=22.365, t=0.317, respectively, both P<0.05), while serum albumin (Alb) and CD4+ T lymphocyte counts were significantly lower in the death group than those in the survival group (t=7.975, Z=-3.073, respectively, both P<0.05). Multivariate logistic regression analysis showed that consciousness disorder and Alb were independent factors influencing the clinical outcome of AIDS patients with CM. Consciousness disorder was related with poor outcome (odd ratio (OR)=26.704, P=0.011, 95% confidence interval (CI) 2.115-337.247), and higher Alb was related with good outcome (OR=0.671, P=0.005, 95%CI 0.507-0.888). The area under the receiver operating characteristic curve of serum Alb for predicting poor outcomes of AIDS patients with CM was 0.932 (95% CI 0.859-0.998, P<0.01). By using 31.7 g/L as cut-off value, the sensitivity was 95% and the specificity was 81% for predicting poor outcome.@*Conclusions@#AIDS complicated with CM has a high mortality rate, and its clinical features are lack of specificity. Consciousness disorder and Alb are independent prognosis factors.
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Objective: To explore deep vein thrombosis (DVT) occurrence in patients after right heart catheterization and the effect of anticoagulant therapy. Methods: A total of 171 consecutive patients with electrophysiological study (EPS) and/or radiofrequency catheter ablation (RFCA) in our hospital from 2015-01 to 2016-05 were enrolled. All patients had supra-ventricular tachycardia and completed a venous surgery, they were randomly divided into 2 groups: Anticoagulation group,n=87 and Non-anticoagulation group,n=84. Lower extremity vascular Doppler ultrasonography was performed at (24-48) h post-operation to compare the incidence of DVT between 2 groups. Results: There were 13/171 patients were excluded for not completing post-operative lower extremity vascular Doppler ultrasonography including 9 patients in Anticoagulation group and 4 in Non-anticoagulation group. 158 patients finished post-operative examination and follow-up study. Anticoagulation group had 7/78 (8.97%) patients suffered from DVT, Non-anticoagulation group had 41/80 (51.3%) patients suffered from DVT,P<0.001. Conclusion: The incidence of DVT was higher after right heart catheterization without anticoagulation; heparin treatment may reduce DVT occurrence in relevant patients.
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Objective To detect the reactive samples of enzyme-linked immunosorbent assay (ELISA1) by chemiluminescence microparticle immunoassay (CMIA),and to analyze the application value of CMIA in HCV infection validation of blood donors.Methods Nucleic acid 3-item combined testing (NAT),another ELISA2,HCV antibody supplementary test(Western Blot test,WB) and CMIA test supplemented in blood samples of 102 ELISA1 anti-HCV reactive blood donors were retrospectively analysed.Results Among 102 blood donors of anti-HCV positive,32 cases (31.37%,32/102) were HCV RNA reactive samples,50 cases (49.02%,50/102) were ELISA2/WB reactive simultaneously.With CMIA NAT results as the reference standard,CMIA was poorly correlated with HCV RNA (Spearman correlation coefficient rs=0.395,P<0.01),and the consistency between them was weak by Kappa test (Kappa=0.270,P<0.01).With ELISA2/WB detection results as the reference standard,CMIA was highly correlated with the results(Spearman correlation coefficient rs=0.713,P<0.01),and which showed high consistency by Kappa test (Kappa=0.674,P<0.01).Conclusion CMIA as a detection method of protein label after HCV infection has great value in the HCV infection confirmation in low-risk population.
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Objective To evaluated the HCV genotyping results which obtained by genotype diagnostic kit in Shenzhen area. Methods 158 samples which ELISA test of anti-HCV were positive were collected from voluntary blood donors from 2014 to 2015,and were tested by PCR fluorescence probe method for viral load.The samples which viral load were greater than 1.0 ×103 IU/mL were then tested by HCV RNA genotype diagnostic kit.To analysis the proportion of different genotypes and the correla-tion between genotypes with vrial load.Results 54 HCV RNA reactive sample were quantity by PCR fluorescence probe method from 158 anti-HCV positive samples.The genotyping data for 45 cases which vrial load greater than 1.0×103 IU/mL were obtained by HCV RNA genotype diagnostic kit.The frequencies HCV genotype 1b,2,3 and 6 were 57.78%(26/45),6.67%(3/45),8.89%(4/45)and 26.67%(12/45),respectively.One-way ANOVA analysis showed that significant difference in viral loads was found be-tween different HCV genotype 1b and 2(F =2.861,P <0.05),and there was a significant difference in viral loads and anti-HCV S/CO by sex(P <0.05).Fisher′s exact test showed the significance difference between age and genotypes(P <0.05 ).Conclusion HCV 1b and 6 were the most predominant genotypes due to the higher viral load than the other subtypes among volunteer blood do-nors in Shenzhen,while the proportion of HCV 2,3 declined.
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Double-stranded oligomeric nucleotide encoding PEP-1 peptides was synthesized, prokaryotic expression pET15b-pep-1-p27mt recombinant constructed, E. coli BL21 (DE3)pLysS transformed and induced with IPTG to highly express fusion protein PEP-1-P27mt. Fusion protein with an N-terminal His-tag could be purified by Ni2+-resin affinity chromatography and identified by SDS-PAGE and Western blotting. Cultured EC9706 cells treated with PEP-1-P27mt revealed that PEP-1-P27mt was transduced into cells after 15 min and reached maximal intracellular concentrations in 2 h. PEP-1-P27mt of 1 μmol/L final concentration could most strongly suppress the growth. It was suggested that PEP-1 can carry P27mt across membrane, which provides a new biological protocol for using cyclin dependent kinase inhibitors p27mt in suppressing the growth of tumor cells.
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Double-stranded oligomeric nucleotide encoding PEP-1 peptides was synthesized, prokaryotic expression pET15b-pep-1-p27mt recombinant constructed, E. coli BL21 (DE3)pLysS transformed and induced with IPTG to highly express fusion protein PEP-1-P27mt. Fusion protein with an N-terminal His-tag could be purified by Ni2+-resin affinity chromatography and identified by SDS-PAGE and Western blotting. Cultured EC9706 cells treated with PEP-1-P27mt revealed that PEP-1-P27mt was transduced into cells after 15 min and reached maximal intracellular concentrations in 2 h. PEP-1-P27mt of 1 micromol/L final concentration could most strongly suppress the growth. It was suggested that PEP-1 can carry P27mt across membrane, which provides a new biological protocol for using cyclin dependent kinase inhibitors p27mt in suppressing the growth of tumor cells.
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Ethylene regulates sex expression in cucumber plants (Cucumis sativus L.). ACC synthase is a key factor during the ethylene biosynthesis. Pairs of PCR primers were synthesized corresponding to the conserved sequences of ACC synthase gene family. The 1 188 bp DNA fragment of ACC synthase gene (CS-ACS2) was amplified from genomic DNA of 8 different sexual phenotypes of cucumber respectively (GenBank accession number is DQ115884～DQ115886 and DQ115875～DQ115879). 8 SNPs have been identified by sequences analysis between 3 monoecious lines and 5 subgynoecious lines and gynoecious lines, which including 4 A←→G and 4 T←→C transition. Of these 8 SNPs, one locus is in intron and 7 loci in exons. Of the 7 SNPs located in exons, 3 SNPs are non-coding SNPs and 4 SNPs are coding SNPs (cSNPs) of which 3 induced changes of encoding amino acid of ACC synthase. The results of SNPs from subgynoecious lines and gynoecious lines suggest that single nucleotide mutation events of CS-ACS2 might be correlated with the development of subgynoecious lines and gynoecious lines in cucumber. Furthermore, CAPS marker C-MT705 was developed for identifying elite subgynoecious cultivar MT-705, which could be valuable in cucumber breeding. Besides, the SNPs and CAPS markers obtained in the study enriched molecular markers of cucumber.