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ABSTRACT Introduction: In Brazil, the blood donor screening for hepatitis B virus (HBV) includes laboratory testing for serological (HBsAg and Anti-HBc) and molecular (HBV DNA) markers. This study aims to correlate serology reactive results with HBV DNA detection among blood donors with at least one HBV infection marker detected in a blood bank in northern Brazil. Method: A retrospective search for HBV reactive blood donor data from January 2017 to December 2019 was performed. Serological screening was performed by chemiluminescent microparticle immunoassays Architect HBsAg and Architect Anti-HBc, whereas molecular screening was performed by the HBV nucleic acid test (HBV NAT). Main results: A total of 556 HBsAg reactive results were detected, between positive (47.66%) and inconclusive (52.34%). A total of 3,658 Anti-HBc reactive results were detected, between positive (83.71%) and inconclusive (16.29%). None of the inconclusive results were associated with HBV DNA detection. The HBV DNA detection rates were 47.55% among HBsAg positive samples and 4.08% among Anti-HBc positive samples. The signal-to-cutoff (S/CO) ratio median of HBV NAT positive samples was superior in comparison to HBV NAT negative samples (p < 0.0001). The thresholds found to optimize sensitivity and specificity were 404.15 for Architect HBsAg and 7.77 for Architect Anti-HBc. Three blood donors were in the window period and 1 occult HBV infection case was detected. Conclusion: High S/CO ratios were more predictive of HBV DNA detection. However, a number of HBV NAT positive samples gave low values, while some HBV NAT negative samples showed high values, reaffirming the significance of molecular testing to enhance transfusion safety.
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Background: Tuberculosis (TB) caused by Mycobacterium tuberculosis (Mtb) is still a major public health concern around the world. Prompt detection of active tuberculosis cases helps in timely therapeutic intervention and reduces community transmission. Despite limited sensitivity, conventional microscopy is still used to diagnose pulmonary tuberculosis in high-burden nations such as India. This study, therefore, was aimed at assessing the diagnostic performance of microscopy by Ziehl Neelsen (ZN) and auramine (AO) staining in the diagnosis of pulmonary tuberculosis. Materials and methods: A prospective comparative study was done on the sputum samples of 2,395 adult patients from November 2018 to May 2020 suspected of having pulmonary tuberculosis visiting the Designated Microscopic Centre of SGT Medical College, Budhera, Gurugram. Each sample was subjected to ZN staining, and AO staining as per NTEP guidelines. Results: Out of the 2,395 samples studied, 161 (6.76%) and 224 (9.35%) were positive by ZN and AO staining methods respectively. Pauci-bacillary cases detected by AO were more than ZN staining. There were 63 more sputum samples detected by AO staining which were missed by ZN microscopy. Conclusion: When compared to conventional ZN staining, the auramine staining technique is more sensitive and takes less time to diagnose pulmonary tuberculosis
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Backgroung: Brazil was slow to implement an expanded testing policy for COVID-19, which may have affected the most vulnerable population's access to testing services.Objective: to evaluate the factors associated with performing the molecular test for COVID-19.Methods: cross-sectional study of secondary data from the COVID-19 panel in the state of Espírito Santo. COVID-19 suspicion notification forms were included between September 11, 2020 and March 2, 2021. Hierarchical logistic regression was used to estimate the odds ratio (OR) with 95% confidence interval (CI95%).Results: 419,771 notification forms were analyzed. The prevalence of performing the molecular teste for COVID-19 was 81.1% (CI95% 81.0-81.2). Elderly (OR= 2.70 CI95% 2.56-2.85), health professional (OR=1 .43 CI95% 1.36-1.50), chronic cardiovascular disease (OR=1.13 CI95% 1.09-1.17), diabetes mellitus (OR=1.07 CI95% 1.01- 1.14) and hospitalization (OR=5.95 CI95% 4.53;7.82) were more likely to have undergone the molecular test. Male sex (OR=0.96 CI95% 0.94-0.98), black skin color (OR=0.75 CI95% 0.73-0.78), yellow skin color (OR=0.74 CI95% 0.71-0.77), residing in the northern health region (OR=0.37 CI95% 0.36-0.39) and the homeless population (OR=0.76 CI95% 0.67-0.85) had the lowest chance of having undergone the molecular test.Conclusion: Social, economic, contextual factors and the risk of aggravation of the disease were associated with carrying out the molecular test for COVID-19 in the state of Espírito Santo. Actions are needed to guarantee the access of the most vulnerable population to molecular testing.
Introdução: o Brasil demorou a implementar uma política de testagem ampliada para COVID-19 no qual pode ter afetado o acesso da população mais vulnerável aos serviços de testagem.Objetivo: analisar os fatores associados à realização de testes moleculares para o diagnóstico da COVID-19.Método: estudo transversal de dados secundários do painel COVID-19 do estado do Espírito Santo. Foram incluídas fichas de notificação de suspeita de COVID-19 entre 11 de setembro de 2020 a 02 de março de 2021. Empregou-se regressão logística hierárquica para estimativa de razão de chances (odds ratio, OR) com intervalo de confiança de 95% (IC95%).Resultados: Foram incluídos no estudo 419.771 fichas de notificação. A prevalência da realização do teste molecular para COVID-19 foi 81,1 % (IC95% 81,0%;81,2%). Idosos (OR= 2,70 IC95% 2,56-2,85), profissional da saúde (OR=1,43 IC95% 1,36-1,50), doença cardiovascular crônica (OR=1,13 IC95% 1,09-1,17), diabetes mellitus (OR=1,07 IC95% 1,01-1,14) e hospitalização (OR=5,95 IC95% 4,53;7,82) apresentaram maior chance de ter realizado o teste molecular. Sexo masculino (OR=0,96 IC95% 0,94-0,98), cor da pele preta (OR= 0,75 IC95% 0,73-0,78), cor da pele amarela (OR=0,74 IC95% 0,71-0,77), residir na região norte de saúde (OR=0,37 IC95% 0,36-0,39) e a população em situação de rua (OR=0,76 IC95% 0,67-0,85) apresentaram a menor chance de ter realizado o teste molecular.Conclusão: Fatores sociais, econômicos e o risco de agravamento da doença foram associados a realização do teste molecular para COVID-19 no estado do Espírito Santo. É necessário ações que garantam o acesso da população mais vulnerável ao teste molecular.
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Abstract Objective The present study aims to highlight the significance of the nucleic acid test (NAT) for musculoskeletal tissue donation and to compare the sensitivity of this test on the different available platforms. Method The present study is a retrospective survey in a human tissue bank database and an integrative literature review encompassing the last 10 years. The PubMed portal and the SCOPUS, CINAHL, and Web of Science databases were queried for articles. Results We found no specific studies on the use and sensitivity of NAT in braindead tissue donors. The information presented in the present study consists of specific contents intended for the Brazilian Blood Transfusion Network (Hemorrede Transfusional Nacional, in Portuguese) and internal retrospective data from a tissue bank located at a city in the state of São Paulo, Brazil. Conclusions The NAT is effective in blood samples from living patients. However, since biochemical reactions in braindead patients can be different, specific research, platforms, or both are crucial to tissue banks.
Resumo Objetivo Evidenciar a importância da realização do teste de ácido nucleico (NAT, na sigla em inglês) para doação de tecidos musculoesqueléticos, assim como comparar a sensibilidade deste exame nas diferentes plataformas existentes no mercado. Método Trata-se de um levantamento retrospectivo no banco de dados de um determinado Banco de Tecidos Humanos e de uma revisão integrativa da literatura, operacionalizada nos últimos 10 anos. As buscas de artigos ocorreram no portal PubMed e nas bases de dados SCOPUS, CINAHL e Web of Science. Resultados Não foram encontrados estudos específicos sobre a utilização e a sensibilidade do exame NAT em pacientes doadores de tecidos com morte encefálica (ME), sendo as informações apresentadas no presente estudo conteúdos específicos destinados à Hemorrede Transfusional Nacional e aos dados retrospectivos internos de um Banco de Tecidos do interior do estado de São Paulo, Brasil. Conclusões O exame NAT se apresenta efetivo em amostras de sangue de pacientes vivos. Porém, reações bioquímicas em pacientes com condições de ME podem se apresentar de formas diferenciadas, tornando-se indispensáveis a realização de pesquisas específicas e/ou a indicação de plataformas aos Bancos de Tecidos.
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Humans , Nucleic Acids , Donor SelectionABSTRACT
@#Objective To prepare the national reference panel of hepatitis B virus(HBV) for nucleic acid testing(NAT)donor screening.Methods A number of plasma samples from donors positive for HBV antibody and patients with HBV infection collected from blood centers,plasma stations and biological products companies in Shanghai,Gansu,Henan,Hunan,Hubei and other regions were tested for HBV DNA viral load agent,and negative and positive reference candidates were screened;The HBV DNA national standard was diluted to 10~3 IU/ml with human negative plasma,as a candidate for limit of detection(LOD).National negative and positive reference candidates of HBV for NAT donor screening and LOD reference to be calibrated were distributed to 8 enterprise laboratories for joint detection of HBVHCVHIV NAT donor screening.The homogeneity and stability of the national reference panel were investigated.Results A total of 8 negative samples with HBV viral load of 0 were screened as negative references and 9 positive samples with viral load of 10~3～10~4 IU/mL were used as positive references;One LOD reference was calibrated with WHO HBV DNA standard,and the virus content was 1.0 × 10~3 IU/ml.The national reference panel showed good stability and the homogeneity inspection met the requirements.Conclusion The national reference panel of HBV DNA for NAT donor screening was prepared,which provided a basis for the quality control and standardization of HBV DNA reagents for donor screening.
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Objective:To compare the cost-effectiveness of hospitalized Chinese patients undergoing nucleic acid screening strategies for hepatitis B and hepatitis C, immunological screening strategy, and no screening strategy under different willingness to pay (WTP). The results might aid to decision-making for the optimal strategy.Methods:In this study, nucleic acid screening, immunological screening and no screening were used as screening strategies, and China′s GDP in 2021 (80 976 yuan) was used as the threshold of WTP to construct a Markov model. After introducing parameters related to the diagnosis and treatment of hepatitis B and C in inpatients, a cohort population of 100 000 inpatients was simulated by TreeAge Pro 2021 software, the total cost, total health effects, incremental cost-effectiveness ratio and average cost-effectiveness ratio of different screening strategies were calculated, and cost-effectiveness analysis was conducted. Univariate and probabilistic sensitivity analysis were used to assess the impact of parameter uncertainty on the final results.Results:Compared with the non-screening strategy, the incremental total cost of the hepatitis B immunological screening strategy for cohort patients was 11 049 536 yuan, and the incremental cost-effectiveness ratio was 24 762 yuan/quality-adjusted life years (QALY), while the total incremental cost of nucleic acid screening was 19 208 059 yuan, and the incremental cost-effectiveness ratio was 29 873 yuan/QALY; the incremental cost-effectiveness ratio of nucleic acid screening and immunological screening was 45 834 yuan/QALY. Compared with the non-screening strategy, the incremental cost-effectiveness ratio of hepatitis C immunological screening strategy was 5 731 yuan/QALY, the incremental cost-effectiveness ratio of nucleic acid screening strategy was 8 722 yuan/QALY, the incremental cost-effectiveness ratio of nucleic acid screening and immunological screening was 45 591 yuan/QALY. The results of probabilistic sensitivity analysis showed that when the cost of nucleic acid testing exceeded 214.53 yuan, it was not cost-effective to perform hepatitis B nucleic acid screening under the WTP as 1 fold GDP. When the cost of nucleic acid testing exceeded 132.18 yuan, it was not cost-effective to conduct hepatitis C screening under the WTP as 1 fold GDP.Conclusions:Nucleic acid screening strategy can achieve more cost-effectiveness and is worthy of vigorous promotion. Compared with no screening, both the nucleic acid and immunological screening strategies are cost-effective, and hepatitis nucleic acid screening is the optimal strategy for hospitalized patients.
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Objective:This multi-centre study was conducted to assess the efficacy of various preoperative/pre-transfusion screening methods for blood transmitted disease.Methods:From July 2021 to December 2021, plasma samples of patients admitted to 10 hospitals were collected for screening preoperative/pre-transfusion blood transmitted disease. Nucleic acid detection technology was used to detect hepatitis B virus (HBV) DNA, hepatitis C virus (HCV) RNA and human immunodeficiency virus (HIV)(1+2) RNA, and the results were compared with the immuno-serological methods. χ 2 test and Kappa test were used to analyze the efficacy of these two methods. Results:A total of 8 655 valid specimens were collected from 10 hospitals. There was a statistically significant difference in the positive detection rate of HCV between the two methods ( P<0.001). There was no significant difference in the positive detection rate of HBV and HIV assessed by the two methods ( P>0.05), but the number of positive cases detected by HBV DNA and HIV RNA (218 and 4 cases) was significantly higher than the corresponding serological results (216 and 2 cases). At the same time, there were HBV, HCV and HIV immuno-serological omissions by the immuno-serological methods, among which 28 cases were HBsAg negative and HBV DNA positive, 2 cases were HCV antibody negative and HCV RNA positive, and 2 cases were HIV antigen/antibody negative and HIV RNA positive. In addition, in the 66 samples with inconsistent results from the two detection methods, 83.3% (55/66), 68.2% (45/66), 63.6% (42/66) and 62.1% (41/66) of patients aged was>45 years, tumor, surgery and male, respectively. Conclusions:Compared with immuno-serological tests, nucleic acid tests have the advantage in terms of sensitivity on detecting HBV, HCV and HIV infection and could reduce missed detection. The risk of transmission can be reduced by adding HBV, HCV, and HIV nucleic acid tests to preoperative/pre-transfusion immuno-serological tests screening for patients over 45 years of age and tumor patients.
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Objective:To explore clinical value of nucleic acid detection for hepatitis B virus (HBV) screening in hospitalized patients.Methods:This cross-sectional study collected and analyzed plasma samples from patients admitted to 10 domestic medical institutions from July 2021 to December 2021. Serological immunoassay and nucleic acid screening were used to simultaneously detect hepatitis B markers such as hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (HBsAb), hepatitis B e Antigen (HBeAg), hepatitis B e antibody (HBeAb), hepatitis B core antibody (HBcAb),and HBV DNA. Statistical analysis was performed on the serology, nucleic acid test results and clinical information of the patients.Results:Of the 8 655 collected samples, HBsAg was positive in 216 (2.50%) samples,HBV DNA was positive in 238 (2.75%) samples ( P>0.05); 210 (2.43%) samples were positive for both HBsAg and HBV DNA, 28 (0.32%) were HBsAg negative and HBV DNA positive, 6 cases (0.07%) were HBsAg positive and HBV DNA negative. Conclusion:These results indicate that the HBV DNA testing is equally effective as hepatitis B virus serological detection for hepatitis B virus screening in hospitalized patients.
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Objective:To explore the clinical significance of hepatitis B virus (HBV) DNA detection in screening patients with hepatitis B.Methods:Clinical data of 682 331 hepatitis B patients were retrospectively analyzed. The HBV DNA of these patients was detected in the Fifth Medical Center of the PLA General Hospital from January 2017 to December 2021, there were 481 159 males and 201 172 females in this cohort, the average age was (41.34±16.13) years. Patients were divided into HBV DNA positive group (219 879 cases) and HBV DNA negative group (462 452 cases). Clinical characteristics, data of five serologic markers of hepatitis B and hepatitis B surface antigen quantification (HBsAg-QN), liver function, alpha fetoprotein (AFP) and prothrombin time (PT) results were collected and analyzed and compared between the two groups.Results:The positive rate of HBV DNA was 32.22% (219 879/682 331) in this cohort. Among the different age groups, the positive rate of HBV DNA was the highest (40.34%, 128 038/317 380) in young people aged 18-44 years. The proportion of patients was lower among aged <1, 45-59 and ≥60 years patients in HBV DNA positive group than that in HBV DNA negative group, while the proportion of patients was higher among aged 1-17 and 18-44 years patients in HBV DNA positive group than that in HBV DNA negative group (all P<0.001). Among 2 291 <1-year-old infants tested for HBV DNA, 71 infants were HBV DNA positive. The positive rates of HBV DNA from 2017 to 2021 were 4.86% (27/556), 3.68% (14/380), 3.47% (17/490), 1.55% (6/386) and 1.46% (7/479) respectively, showing a downward trend year by year. The positive rate of HBV DNA in acute hepatitis B (AHB) patients was the highest (49.88%, 208/417) among 680 040 patients with hepatitis B. The proportion of AHB patients (0.09%, 208/219 808) and chronic hepatitis B (80.44%, 176 806/219 808) in HBV DNA positive group was higher than that in HBV DNA negative group [0.05% (209/460 232) and 65.45% (301, 216/460 232)], while the proportion of patients with HBV-related liver cirrhosis (11.28%, 24 793/219 808), HBV-related liver cancer (6.72%, 14 775/219 808), liver cancer surgery (1.39%, 3 055/219 808) and liver transplantation (0.08%, 171/219 808) were lower than that in HBV DNA negative group [22.99% (105 813/460 232), 7.25% (33 385/460 232), 3.50% (16 129/460 232) and 0.76% (3 480/460 232)] (all P<0.001). At the same time, positive rate of hepatitis B surface antigen (HbsAg), HBsAg-QN, hepatitis B e antigen (HbeAg), level of total bilirubin, total bilirubin, AFP and PT were higher in HBV DNA positive group than those in HBV DNA negative group, while the age, male ratio and albumin results in HBV DNA positive group were lower than those in HBV DNA negative group (all P<0.01). The HBV DNA loads were higher in HBsAg positive group, hepatitis B surface antibody positive group and HBeAg positive group than those in respective negative groups, while the HBV DNA loads were lower in hepatitis B e antibody positive group and hepatitis B core antibody positive group than those in respective negative groups (all P<0.001). Conclusions:The mother to child transmission rate of<1-year-old infants decreases year by year. HBV DNA is an important factor for the progression of hepatitis B disease. HBV DNA positive hepatitis B patients with higher HBsAg-QN values are more likely to have abnormal serum markers such as liver dysfunction. HBV DNA detection is therefore of clinical importance in screening patients with hepatitis B.
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For patients with chronic hepatitis B, the indications of antiviral treatment are gradually expanding, and the pursuit of various degrees of cure (partial cure, functional cure and complete cure) is consistently improving, which enhances the urgent clinical need for improving the detection sensitivity of hepatitis B virus (HBV) surface antigen and DNA. Based on the availability of commercial highly sensitive hepatitis B surface antigen and HBV DNA detection reagents, we summarized their applications in the diagnosis of HBV infection, their role on guiding selection of antiviral treatment agents and treatment plans, their prediction efficacy and indication for drug withdrawal, their role on monitoring therapy efficacy and the prediction of disease outcomes. Taken together, highly sensitive hepatitis B virus surface antigen and DNA assays and related detection technology play an important role in the whole management process of chronic HBV infection.
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Objective:To analyze the genetic variation characteristics of the HA gene of influenza A virus (H3N2) in Guizhou province from 2017 to 2019. Methods:Twenty strains of influenza A virus (H3N2) were randomly selected from 10 network laboratories in Guizhou province for RNA extraction. Reverse transcriptase-polymerase chain reaction and sequencing were performed. The products were analyzed using bioinformatics software.Results:The nucleotide homology of the HA gene of the 20 strains was 97.7%-100%, which was highly homologous to the vaccine strains A/Hong-Kong/4801/2014 recommended by WHO in 2017 and A/Singapore-INFIMH/16-0019/2016 recommended by WHO in 2018, but they were significantly different from the vaccine strain A/Kansas/14/2017 recommended by WHO in 2019. Genetic analysis showed that the 20 strains were divided into two branches, and the strains that were prevalent in 2019 were located in different branches, with marked genetic differences. Key site analysis showed mutations in antigenic determinants A, B, C, and E and mutations in the anterior and posterior walls of receptor binding sites. Key site analysis also showed that there was an increase in the number of glycosylation sites compared with the vaccine strains prevalent in the same year. Genetic distance, antigen sites, and glycosylation sites were slightly different between virus strains prevalent in 2017-2018 and virus strains prevalent in 2019. Conclusion:The HA gene of the influenza A virus subtype H3N2 in Guizhou province from 2017 to 2019 showed heterogeneity and gene mutation, especially in 2019. Therefore, close monitoring of the genetic evolution of the influenza A virus subtype H3N2 is necessary.
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The spread, prevention and control of novel coronavirus infection and the potential risks and uncertainties of novel coronavirus transmission from donor to recipient have brought serious impacts and great challenges to organ donation and transplantation. There is increasing evidence that the use of non-pulmonary organs (kidney, liver and heart) from novel coronavirus infected donors carries a low risk of transmission, regardless of whether they were symptomatic at the time of acquisition. Delaying organ donation after the death of those who are positive for novel coronavirus antigen or nucleic acid testing, and then waiting until turns negative, will result in the discarding of a significant number of organs that are medically suitable for transplantation. In order to maximally meet the demand for transplantation in patients with end-stage organ failure, Branch of Organ Transplantation of Chinese Medical Association organized relevant experts formulated the "Expert consensus on organ donation from patients infected with novel coronavirus in China" after citizen' s death by taking into account the epidemic situation of novel coronavirus infection in China and the clinical practice of organ donation and transplantation, and by referring to relevant research results and clinical research evidence at home and abroad. It aims to provide recommendations and references for the procurement and application of donor organs from patients infected with novel coronavirus.
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@#Objective To analyze the influencing factors for re-positive nucleic acid test in discharged corona-virus disease 2019 (COVID-19) patients in Chengdu, Sichuan Province, and to provide data support for the epidemics prevention and control. Methods The clinical data of 660 discharged COVID-19 patients from January 23, 2020 to February 28, 2021 in our center were retrospectively analyzed. The patients were divided into two groups according to the reexamination of virus nucleic acid, including a negative group [549 patients, including 428 males and 121 females with a median age of 33.0 (28.0, 48.0) years] and a positive group [111 patients, including 76 males and 35 females with a median age of 39.0 (28.0, 51.0) years]. The clinical data of the two groups were compared. Results The re-positive rate of the discharged patients was 16.82%. Univariate analysis showed that the re-positive rate of females was higher than that of males (χ2=4.608, P=0.032). The re-positive rate of confirmed patients was higher than that of asymptomatic infected patients (χ2=8.140, P=0.004). The re-positive rate of domestic patients was higher than that of imported patients (χ2=9.178, P=0.002). The counts of CD3+ (P=0.038), CD4+ (P=0.048) and CD8+ (P=0.040) T lymphocytes in the negative group were higher than those in the positive group. The binary logistic regression analysis showed that the clinical classification and CD8+ T lymphocyte count were independent risk factors affecting the recurrence of virility. Conclusion The gender, origin, T lymphocyte subsets count and clinical type are the influencing factors for re-positive result, and clinical type and CD8+ T lymphocyte count are the independent influencing factors for re-positive result. Therefore, improving the immunity of infected patients, as well as early detection and timely treatment are effective means to reduce the re-positive occurrence.
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Rapid, sensitive and specific detection tools are critical for the prevention and control of infectious diseases. The in vitro nucleic acid amplification assays, including polymerase chain reaction and isothermal amplification technology, have been widely used for the detection of pathogens. Recently, nucleic acid detection-based on clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated proteins (Cas) have been developed, which are rapid, highly sensitive, highly specific, and portable. This review describes the classification and principle of CRISPR/Cas systems and their applications in pathogen detection, and discusses the prospects of CRISPR/Cas systems.
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@#By regulating gene expression, nucleic acid drugs functioning in the cytoplasm or nucleus are of great significance in the treatment of acquired or inherited diseases and vaccine development.A variety of nucleic acid delivery vectors currently developed are suffering from low transfection efficiency due to endosome/lysosome entrapment.This paper introduces and summarizes the nucleic acid delivery strategies that bypass the endosomal/lysosomal pathway, including membrane translocation, membrane fusion, receptor/transporter-mediated non-endocytic uptake and caveolae-mediated endocytosis, and discusses the problems and challenges facing such strategies, aiming to facilitate the development of intracellular delivery of nucleic acid drugs bypassing lysosomal pathway.
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Due to long-term use of immunosuppressive agents, solid organ transplant recipients (SOTR) belong to high-risk populations of multiple pathogenic infection, including SARS-CoV-2. In addition, SOTR are constantly complicated by chronic diseases, such as hypertension and diabetes mellitus, etc. After infected with SARS-CoV-2, the critically ill rate and fatality of SOTR are higher than those of the general population, which captivates widespread attention from experts in the field of organ transplantation. Omicrone variant is currently the significant pandemic strain worldwide, rapidly spreading to more than 100 countries worldwide and causing broad concern. According to the latest international guidelines on the diagnosis and treatment of SARS-CoV-2 infection and relevant expert consensus in China combined with current domestic situation of SARS-CoV-2 pandemic and China's "diagnosis and treatment regimen for SARS-CoV-2 infection (Trial Version 10)", the epidemiology, clinical manifestations and prognosis, diagnosis, clinical classification and treatment of SARS-CoV-2 infection were briefly reviewed.
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ObjectiveTo establish a method for seahorse identification based on graphene oxide fluorescence sensing technology， and to provide a new research idea for identification of traditional Chinese medicine. MethodThe fluorophore FAM was labeled at the 5' end of the specificity upstream primer Ja-F of Hippocampus japonicus as the nucleic acid probe FAM-ssDNA （single strand DNA）. The recognition site of RNA polymerase Ⅱ was added to its specific downstream primer Ja-R as Ja-R1. The seahorse samples were amplified with Ja-F/Ja-R1 primers， and the ssDNA of H. japonicus was obtained by reverse transcription of the amplification products using vitro transcription method. The 20 μL nucleic acid probe FAM-ssDNA （500 nmol·L-1） was incubated at 90 ℃ for 5 min， and was gradually cooled to room temperature. Different volume of graphene oxide solution （100 mg·L-1） and Tris hydroxymethyl amino methane HCl （Tris-HCl） buffer （50 mmol·L-1） were added into each probe solution to make a final reaction volume of 1 mL. The fluorescence intensity of each sample was measured after mixing and placing different times at room temperature away from the light. So that the most appropriate graphene oxide concentration and reaction time were screened for constructing the best nucleic acid probe-graphene oxide biosensor. Adding probe complementary sequence FAM-ssDNA-match solution into the nucleic acid probe-graphene oxide solution， the fluorescence intensity of the reaction mixture was measured after being placed different times at room temperature. Therefore， the optimal reaction time of fluorescence recovery was screened and the feasibility of the sensor was tested. The sensitivity was detected via adding ddH2O as the blank control and different concentration H. japonicus ssDNA into each nucleic acid probe-graphene oxide solution， respectively. Finally， the commercial hippocampal were identified using the optimal experimental condition， and the feasibility of this method for the identification of Chinese medicinal materials was verified. ResultThe fluorescence of 1 mL reaction mixture including 10 nmol·L-1 nucleic acid probe FAM-ssDNA and 12 mg·L-1 go solution for 20 min at room temperature away from the light could be completely quenched. Feasibility test of the biosensor showed that when probe complementary sequence FAM-ssDNA-match solution （final concentration 90 nmol·L-1） was added to the biosensor solution and reacted 1 h reaction at room temperature， the fluorescence signal was significantly enhanced. Sensitivity test showed that the minimum concentration of ssDNA detected by this method was about 10 mg·L-1. This method was used to detect commercial seahorses， and only H. japonicus samples had obvious fluorescence signal. ConclusionThe graphene oxide-based fluorescent sensing technology could be used for zoological origin survey of commercial hippocampus.
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@#Abstract: Objective To compare the diagnostic efficacy of the upgraded version of the GeneXpert automated fluorescent quantitative PCR system (GeneXpert MTB/RIF Ultra, GeneXpert Ultra) and the original version of the GeneXpert system (GeneXpert MTB/RIF, Xpert), real-time fluorescent quantitative nucleic acid detection (FQ-PCR), real-time fluorescent thermostatic amplification of Mycobacterium tuberculosis RNA (SAT-RNA), real-time fluorescent thermostatic amplification detection of DNA (thermostatic amplification method) and traditional BACTEC MGIT 960 liquid culture (culture method) for special specimens of tuberculosis, in order to analyze its application value in clinical detection. Methods Using prospective research methods, a total of 170 special specimens (including 47 pleural and ascites effusion samples, and 34 24-hour urinary sediment specimens, 49 tissue specimens and 40 fester specimens) were collected i'an Chest Hospital from January to September 2021. GeneXpert Ultra, Xpert, FQ-PCR, SAT-RNA, isothermal amplification, and traditional culture were used for detection. Clinical diagnosis was used as the standard, and sensitivity, specificity, positive predictive value, negative predictive value, coincidence rate, and Kappa value were compared among the methods. Results The sensitivities of GeneXpert Ultra, Xpert, FQ-PCR, SAT-RNA, isothermal amplification, and traditional culture were 65.18% (73/112), 49.11% (55/112), 37.50% (42/112), 19.64% (22/112), 8.04% (9/112), and 22.32% (25/112), respectively. The sensitivity of GeneXpert Ultra was higher than that of the other five methods, and the differences were statistically significant (χ2=66.25, 42.10, 28.89, 13.09, 4.92, 15.18, all P<0.05). GeneXpert Ultra result analysis showed that: 5.48%(4/73) cases had trace, that is, trace Mycobacterium tuberculosis load, 79.45% (58/73) cases were extremely low, 10.96% (8/73) cases were low, 2.74% (2/73) were medium, , and 1.36% (1/73) were high load. In 4 trace samples, the Xpert detection was negative for all. Of the 73 GeneXpert Ultra positive reports, 63 were rifampicin-sensitive, 6 were rifampicin-resistant, and 4 were rifampicin-resistant but of unclear resistance. Of the 55 Xpert positive reports, 45 were rifampicin-sensitive, 2 were rifampicin-resistant, and 8 were rifampicinresistant but of unclear resistance.. Conclusions The new generation of GeneXpert MTB/RIF Ultra has high sensitivity, specificity and drug resistance detection rate, and its advantage is even more apparent in the pathogenic diagnosis of special specimens of tuberculosis. It can be used as one of the preferred methods in samples with low bacterial load.
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【Objective】 In an effort to prevent transfusion-transmitted hepatitis B infection, universal HBsAg screening, HBsAg+ MP nucleic acid test(NAT) for HBV and HBsAg + individual(ID) NAT were analyzed for cost-effectiveness. 【Methods】 On the basis of screening data and the documented parameter, the number of window period infections, chronic infections and occult infections was constructed, and cost-benefit analysis was conducted. 【Results】 Of 132 208 donations, the yield rate of ID NAT for HBsAg-/DNA+ (0.11%) was significantly higher than HBsAg+ MP NAT(0.058%). Furthermore, the predicted preventing transfusion transmitted HBV cases by ID NAT is 1.25 times as that by MP-6 NAT, so did the benefits. The cost-benefit of the three screening models were 1∶63.6、1∶28.6 and 1∶53.4. 【Conclusion】 Universal HBsAg in combination with ID HBV NAT screening was the most effective among all screening strategy. It is necessary to applied HBsAg and ID HBV NAT screening for the safety of blood transfusion.
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【Objective】 To analyze the reasons for the invalidity of blood nucleic acid test results, and to explore the countermeasures to reduce the invalidity of the test. 【Methods】 From 2019 to 2021, the number of tests performed in our laboratory for Cobas s201 blood nucleic acid screening system and the number of batches and tests with invalid results were counted, and the types and reasons of invalid results were analyzed. 【Results】 From 2019 to 2021, the Cobas s201 nucleic acid detection system detected a total of 5, 420 batches and 127, 950 pools, and the invalid rate of batches and pools were 1.83% and 1.97%, respectively. The types of invalid results can be summarized as improper operation, sample quality problems, invalid quality control (IQC), equipment failure and others. Among them, IQC and equipment failure were the main reasons for invalid results, accounting for 44.51% and 39.96%, respectively. IQC was mainly related to cross-contamination of samples and insufficient mixing of quality control products. Equipment failures mostly occurred in the robotic arm gripper of the nucleic acid extraction instrument and the TC module of the amplification instrument. 【Conclusion】 The laboratory should conduct quality monitoring for invalid results, and take targeted improvement measures, especially to reduce invalid results caused by invalid quality control and instrument failure.