Consecutive positive nucleic acid tests in COVID-19 patients: a retrospective cohort study in Fangcang hospitals, Shanghai.

INTRODUCTION: The coronavirus disease 2019 (COVID-19) spread rapidly in Shanghai in February 2022. Patients with asymptomatic and mild symptoms were admitted to Fangcang shelter hospitals for centralized quarantine. METHODOLOGY: A total of 5,217 non-severe patients hospitalized in the Longyao Fangcang and Shilong Fangcang hospitals were included in the study. Demographic and clinical characteristics, comorbidity, exposure history, treatment and disease duration were analyzed. Univariate analysis and binomial logistic regression analysis were performed to identify the factors influencing nucleic acid change from positive to negative over 14 days. RESULTS: Consecutive positive nucleic acid test results (days) were significantly associated with advanced age (OR = 1.343, 95% CI 1.143 to 1.578, p < 0.001), smoking (OR = 0.510, 95% CI 0.327 to 0.796, p = 0.003) and vaccination (OR = 0.728, 95% CI 0.641 to 0.827, p < 0.001). However, there was no significant difference between asymptomatic and mild symptomatic patients (p = 0.187). In univariate analysis, comorbidities including diabetes, hypertension, cardiovascular system, malignant tumors, autoimmune diseases and cerebral apoplexy were associated with consecutive positive nucleic acid test results, but there was no significant difference in binomial logistics regression analysis. CONCLUSIONS: Aging and comorbid conditions lead to the prolongation of positive nucleic acid test results for several days. Improving vaccination coverage is beneficial for prevention and control of the epidemic. The management and treatment methods of Shanghai Fangcang shelter hospitals had important referential significance, which can provide valuable guidance for the prevention and control of the COVID-19 epidemic in the future.

A cell-free biosensor for multiplexed and sensitive detection of biological warfare agents.

The rapid and precise detection of pathogenic agents is critical for public health and societal stability. The detection of biological warfare agents (BWAs) is especially vital within military and counter-terrorism contexts, essential in defending against biological threats. Traditional methods, such as polymerase chain reaction (PCR), are limited by their need for specific settings, impacting their adaptability and versatility. This study introduces a cell-free biosensor for BWA detection by converting the 16S rRNA of targeted pathogens into detectable functional protein molecules. The modular nature of this approach allows for the flexible configuration of pathogen detection, enabling the simultaneous identification of multiple pathogenic 16S rRNAs through customized reporter proteins for each targeted sequence. Furthermore, we demonstrate how this method integrates with techniques utilizing retroreflective Janus particles (RJPs) for facile and highly sensitive pathogen detection. The cell-free biosensor, employing RJPs to measure the reflection of non-chromatic white light, can detect 16S rRNA from BWAs at femtomolar levels, corresponding to tens of colony-forming units per milliliter of pathogenic bacteria. These findings represent a significant advancement in pathogen detection, offering a more efficient and accessible alternative to conventional methodologies.

Clinical evaluation of a modified SARS-CoV-2 rapid molecular assay, ID NOW ™ COVID-19 2.0.

In the diagnosis of coronavirus disease 2019 (COVID-19), several types of instruments and reagents for SARS-CoV-2 nucleic acid testing have been introduced to meet clinical needs. We evaluated the clinical performances of ID NOW™ COVID-19 2.0 (ID NOW™ 2.0), which is capable of detecting SARS-CoV-2 within 12 min as part of point-of-care testing (POCT). Patients who displayed COVID-19 related symptoms, and who were tested for screening purposes, were recruited to this study. Two nasopharyngeal swabs were collected and tested using the ID NOW™ 2.0 test. Reference testing was performed using the cobas 8800 or 6800 (reagents: cobas SARS-CoV-2 and Flu A/B). A total of 38 samples and 46 samples were tested positive and negative, respectively, by the reference test. The ID NOW™ 2.0 showed a sensitivity of 94.7% (95% CI: 82.3-99.4) and a specificity of 100% (95% CI: 92.3-100). Samples that were positive by reference testing had cycle threshold (Ct) values ranging from 11.90 to 35.41. Among these reference positive samples, two samples were negative by ID NOW™ 2.0 with Ct values of 35.25 and 35.41. For samples with Ct values < 35, the sensitivity of ID NOW™ 2.0 was 100%. In Japan, the restrictions related to COVID-19 have been relaxed, however the COVID-19 epidemic still continues. ID NOW™ 2.0 is expected to be used as a rapid and reliable alternative to laboratory-based RT-PCR methods.

Decreasing parvovirus B19 and hepatitis A nucleic acid test positivity rates in Canadian plasma donors following the initiation of COVID-19 restriction in March 2020.

BACKGROUND AND OBJECTIVES: In Canada, plasma sent for fractionation is tested for both parvovirus B19 (B19V) and hepatitis A virus (HAV). This study compared positivity rates of B19 and HAV nucleic acid tests (NATs) in Canadian plasma samples for the pre-COVID-19 restriction era (2015 to end of February 2020 [Q1] 2020) and the post-COVID-19 restriction era. MATERIALS AND METHODS: Pooled EDTA plasma specimens were tested within 24 months of blood draw using the Procleix Panther System (Grifols Diagnostic Solutions Inc, San Diego, CA, USA) for B19V and HAV detection. Reactive pools were resolved by individual specimen testing. RESULTS: Between 1 January 2015, and 31 March 2022, 3,928,619 specimens from Canadian plasma donors were tested for B19V. For the same period, 3,922,954 specimens were tested for HAV. To account for a lag in specimen testing for up to 24 months, the data were divided into: (1) a pre-pandemic period (1 January 2015-31 March 2020; B19V tested n = 2,412,701, B19V NAT-positive n = 240 [0.01%], HAV tested n = 2,407,036, HAV NAT-positive n = 26 [0.001%]); (2) a two-year mixed-impact period (1 April 2020-31 March 2022; B19V tested n = 968,250, B19V NAT-positive n = 14 [0.001%], HAV tested n = 968,250, HAV NAT-positive n = 2 [0.0002%]); and (3) a pandemic-impact period (1 April 2022-31 March, 2023; B19V tested n = 597,668, B19V NAT-positive n = 3 [0.0005%], HAV tested n = 597,668, HAV NAT-positive n = 1 [0.0002%]). CONCLUSION: The percentage of B19V- and HAV-positive donations was significantly reduced from the pre-pandemic period to the pandemic-impact period.

Validation of a Parvovirus B19 NAT Assay for Screening of Umbilical Cord Blood for Allogenic Hematopoietic Stem Cell Donation.

Introduction: Parvovirus B19 transmitted by umbilical cord blood (UCB) products may cause severe disease in allogenic hematopoietic stem cell transplant recipients. Thus, commercially available nucleic acid test (NAT) assays for highly sensitive detection of parvovirus B19 DNA validated for the specimen cord blood plasma (CBP) are required to avoid parvovirus B19 transmission by umbilical hematopoietic stem cell preparations. Methods: The multiplex cobas DPX NAT assay was validated for detection of parvovirus B19 DNA in CBP derived from citrate anticoagulated UCB units which have been processed by the Rubinstein method. In total, 363 retained CBP samples pretested negative for parvovirus B19 DNA were prepared for analyzing sensitivity, specificity, and interference of that NAT assay. The 3rd WHO International Standard for parvovirus B19 DNA was used for determining the 95% limit of detection (LOD95) by probit analysis. Results: The validation of the parvovirus B19 NAT assay for CBP demonstrated high sensitivity, specificity, intra- and inter-assay precision. Dilution series and replicate analyses showed a high linearity of the assay with a coefficient of determination above 0.99 and revealed a LOD95 of 17 International Units (IU)/mL (95% confidence interval, 14-44 IU/mL) for parvovirus B19 DNA in CBP samples. Conclusion: The validation of a commercially available parvovirus B19 NAT assay for the specimen CBP demonstrated a high assay performance fulfilling German guidelines and international regulations.

Updated Clinical Guidelines on the Management of Hepatitis C Infection in Children.

Children represent only a small proportion of those infected with the hepatitis C virus (HCV) compared to adults. Nevertheless, a substantial number of children have chronic HCV infection and are at risk of complications including cirrhosis, portal hypertension, hepatic decompensation with hepatic encephalopathy, and hepatocellular carcinoma in adulthood. The overall prevalence of the HCV in children was estimated to be 0.87% worldwide. The HCV spreads through the blood. Children born to women with chronic hepatitis C should be evaluated and tested for HCV due to the known risk of infection. The course of treatment for hepatitis C depends on the type of HCV. Currently, there are two pan-genotype HCV treatments (Glecaprevir/pibrentasvir and Sofosbuvir/velpatasvir) for children. We aim to review the updated clinical guidelines on the management of HCV infection in children, including screening, diagnosis, and long-term monitoring, as well as currently published clinical trials and ongoing research on direct acting antiviral hepatitis C treatment in children.

Combination of rRT-PCR and Clinical Features to Predict Coronavirus Disease 2019 for Nosocomial Infection Control.

Background: Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), immediately became a pandemic. Therefore, nosocomial infection control is necessary to screen for patients with possible COVID-19. Objective: This study aimed to investigate commonly measured clinical variables to predict COVID-19. Methods: This cross-sectional study enrolled 1087 patients in the isolation ward of a university hospital. Conferences were organized to differentiate COVID-19 from non-COVID-19 cases, and multiple nucleic acid tests were mandatory when COVID-19 could not be excluded. Multivariate logistic regression models were employed to determine the clinical factors associated with COVID-19 at the time of hospitalization. Results: Overall, 352 (32.4%) patients were diagnosed with COVID-19. The majority of the non-COVID-19 cases were predominantly caused by bacterial infections. Multivariate analysis indicated that COVID-19 was significantly associated with age, sex, body mass index, lactate dehydrogenase, C-reactive protein, and malignancy. Conclusion: Some clinical factors are useful to predict patients with COVID-19 among those with symptoms similar to COVID-19. This study suggests that at least two real-time reverse-transcription polymerase chain reactions of SARS-CoV-2 are recommended to exclude COVID-19.

Rapid detection of Salmonella typhimurium by photonic PCR-LFIS dual mode visualization.

Salmonella spp., as one of the foodborne pathogens, is a severe threat to global public health. Rapid screening of salmonella spp. in contaminated food with low infective doses is the key to preventing food poisoning. In this study, a fast visualization method for detecting Salmonella typhimurium (S. typhimurium) was developed based on photonic PCR and AuNPs lateral-flow immunochromatography strip (LFIS). In addition, quantitative detection of target bacteria could be achieved by utilizing the photothermal effect of AuNPs, and the sensitivity could be improved by amplifying the photothermal signal. On the optimized conditions, the developed photonic PCR-LFIS assay was highly sensitive, with a detection limit as low as 19 cfu mL-1 of bacteria in pure culture after laser irradiation, and highly specific, exhibiting no cross-reaction with Salmonella enteritidis, Listeria monocytogenes, Escherichia coli, and Staphylococcus aureus. Notably, S. typhimurium could be detected in pork, egg white, and milk without pre-treatment, with the recovery rates of the three samples between 81 % and 109 %. In conclusion, the photonic PCR-LFIS assay realizes sensitive, simple, and rapid detection of S. typhimurium.

Implementing Individualized quality control plans and managing risk at the point-of-care for molecular diagnostics.

INTRODUCTION: Faster turnaround times can lead to rapid patient treatment. Implementing a point-of-care (POC) molecular COVID-19 test requires careful planning. In the POC setting, there are numerous operators and regular monitoring of their activities is key to the successful implementation of a POC molecular test. Test errors can arise from samples, operators, reagents, the testing system, and even from the environment. These sources of error should be considered when implementing a new test. AREAS COVERED: We outline the importance of establishing well-defined policies for staff to follow at the preanalytic, analytic and postanalytic phases of SARS-CoV-2 testing. As these factors are crucial for the accuracy and reliability of the test results. The key discussion points are from the CLSI EP23-Ed2 document on developing individualized quality control plans and medical literature search engines such as EMBASE, MEDLINE and MedlinePlus. EXPERT OPINION: The risk management principles applied when implementing nucleic acid POC tests can identify specific control processes to help mitigate common sources of error when conducting molecular testing at the POC.

Impact of Different Traditional Chinese Medicine Constitutions on the Clinical Outcomes of COVID-19 Patients Infected with SARS-CoV-2 Omicron Variant: A Retrospective Observational Study.

Purpose: Traditional Chinese Medicine (TCM) constitution and disease occurrence, development, and prognosis are interrelated. This study aimed to investigate the association between TCM constitution and the time to negative nucleic acid test results in patients with coronavirus disease 2019 (COVID-19) infected with the SARS-CoV-2 Omicron variant. Patients and Methods: We identified COVID-19 patients (≥18 years) infected with the SARS-CoV-2 Omicron variant and collected clinical data, including clinical symptoms, time to negative nucleic acid test results, and TCM constitution. Linear and logistic regression analyses explored the relationship between TCM constitution and the time to negative nucleic acid test results in patients with the COVID-19 Omicron variant. Results: We included 486 patients with COVID-19, with a mean age of 40.2 years; 321 (66.0%) men and 165 (34.0%) women. Balanced constitution accounted for 43.8%, and unbalanced constitution accounted for 56.2%. Chi-square test showed that different TCM constitutions had significant differences in the influence of clinical symptoms of COVID-19 patients (P < 0.01). After controlling for various factors, multiple linear regression analysis revealed that an unbalanced constitution was significantly positively correlated with time to negative nucleic acid test results (P < 0.05). After controlling for various factors, logistic regression analysis revealed that an unbalanced constitution was closely related to the 7-day nucleic acid test conversion rate (odds ratio (OR): 0.53, 95% confidence interval (CI): 0.36-0.80, P < 0.05). After dividing the unbalanced constitution into deficiency constitution and non-deficiency constitution, the non-deficiency constitution was closely associated with the 7-day nucleic acid test conversion rate (OR = 0.45, 95% CI: 0.28-0.74, P < 0.05). Further analysis revealed that damp-heat constitution in the non-deficiency constitution was associated with the 7-day nucleic acid test conversion rate (OR = 0.33, 95% CI: 0.18-0.60, P < 0.05). Conclusion: In patients with COVID-19, an unbalanced constitution is associated with a longer time to negative nucleic acid test results and lower 7-day nucleic acid test conversion rates.

Lipid alternations in the plasma of COVID-19 patients with various clinical presentations.

Background: COVID-19 is a highly infectious respiratory disease that can manifest in various clinical presentations. Although many studies have reported the lipidomic signature of COVID-19, the molecular changes in asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected individuals remain elusive. Methods: This study combined a comprehensive lipidomic analysis of 220 plasma samples from 166 subjects: 62 healthy controls, 16 asymptomatic infections, and 88 COVID-19 patients. We quantified 732 lipids separately in this cohort. We performed a difference analysis, validated with machine learning models, and also performed GO and KEGG pathway enrichment analysis using differential lipids from different control groups. Results: We found 175 differentially expressed lipids associated with SASR-CoV-2 infection, disease severity, and viral persistence in patients with COVID-19. PC (O-20:1/20:1), PC (O-20:1/20:0), and PC (O-18:0/18:1) better distinguished asymptomatic infected individuals from normal individuals. Furthermore, some patients tested positive for SARS-CoV-2 nucleic acid by RT-PCR but did not become negative for a longer period of time (≥60 days, designated here as long-term nucleic acid test positive, LTNP), whereas other patients became negative for viral nucleic acid in a shorter period of time (≤45 days, designated as short-term nucleic acid test positive, STNP). We have found that TG (14:1/14:1/18:2) and FFA (4:0) were differentially expressed in LTNP and STNP. Conclusion: In summary, the integration of lipid information can help us discover novel biomarkers to identify asymptomatic individuals and further deepen our understanding of the molecular pathogenesis of COVID-19.

What contributes to the re-positive nucleic acid test results for the omicron variant of SARS-CoV-2 in the shelter cabin hospital in Shanghai, China?

Background: Despite the increasing reports of re-positive SARS-CoV-2 cases after recovery and discharge from hospitals, our knowledge remains very limited regarding the contributing factors of re-positivity and its roles in the transmission and epidemiology of the Omicron variant. Methods: In this retrospective study, re-positivity is defined as the positive nucleic acid result (Ct < 35) following two consecutive negative results during hospitalization. A total of 751 patients from Shanghai Shelter Cabin Hospital were enrolled and divided with a ratio of about 1:2 into the re-positivity group and the non-re-positivity group. Patients required three consecutive negative results daily as the de-isolation criterion. The follow-up time of discharged patients lasted five weeks. Univariate regression analysis was used to compare variables between the re-positivity and non-re-positivity groups, and the single re-positivity and multiple re-positivity groups, with P < 0.05 defined as the statistical significance of differences. Subsequently, variables with P < 0.2 were subjected to multivariate logistic regression analysis to investigate the odds ratio (OR) of re-positivity and the influencing factors of re-positivity of the Omicron variant. Results: The re-positivity group had a higher proportion of males (68.1% vs 58.1%, p = 0.000), a higher education level (31.9% vs 12.7%, p = 0.007), a longer hospitalization duration (13 days vs 8 days, p = 0.000), and a higher Convidecia vaccination rate (6.0% vs 2.4%, p = 0.011). Further multivariable analysis showed male (OR = 2.168, p = 0.000), Convidecia vaccination (OR = 2.634, p = 0.014), hospitalization duration (OR = 2.146, p = 0.000) and education level (OR = 1.595, p = 0.007) were associated with re-positivity. The average rate of re-positivity was 25% during hospitalization and decreased to 0.4% among discharged patients. Re-positivity was more common in the period with a larger number of hospitalized patients and in larger wards with a larger number of patients. Conclusion: A large number of hospitalized patients, large-sized wards, and gender are significant contributing factors to re-positivity. Division of the shelter cabin hospital into small independent wards and requirement of three consecutive results daily as the de-isolation criterion might be more beneficial to the control and prevention of the spread of the Omicron variant.

[Rapid detection and genotyping of SARS-CoV-2 Omicron BA.4/5 variants using a RT-PCR and CRISPR-Cas12a-based assay].

OBJECTIVE: To establish a rapid detection and genotyping method for SARS-CoV-2 Omicron BA.4/5 variants using CRISPPR-Cas12a gene editing technology. METHODS: We combined reverse transcription-polymerase chain reaction (RT-PCR) and CRISPR gene editing technology and designed a specific CRISPPR RNA (crRNA) with suboptimal protospacer adjacent motifs (PAM) for rapid detection and genotyping of SARS- CoV-2 Omicron BA.4/5 variants. The performance of this RT- PCR/ CRISPPR-Cas12a assay was evaluated using 43 clinical samples of patients infected by wild-type SARS-CoV-2 and the Alpha, Beta, Delta, Omicron BA. 1 and BA. 4/5 variants and 20 SARS- CoV- 2-negative clinical samples infected with 11 respiratory pathogens. With Sanger sequencing method as the gold standard, the specificity, sensitivity, concordance (Kappa) and area under the ROC curve (AUC) of RT-PCR/CRISPPR-Cas12a assay were calculated. RESULTS: This assay was capable of rapid and specific detection of SARS- CoV-2 Omicron BA.4/5 variant within 30 min with the lowest detection limit of 10 copies/µL, and no cross-reaction was observed in SARS-CoV-2-negative clinical samples infected with 11 common respiratory pathogens. The two Omicron BA.4/5 specific crRNAs (crRNA-1 and crRNA-2) allowed the assay to accurately distinguish Omicron BA.4/5 from BA.1 sublineage and other major SARS-CoV-2 variants of concern. For detection of SARS-CoV-2 Omicron BA.4/5 variants, the sensitivity of the established assay using crRNA-1 and crRNA-2 was 97.83% and 100% with specificity of 100% and AUC of 0.998 and 1.000, respectively, and their concordance rate with Sanger sequencing method was 92.83% and 96.41%, respectively. CONCLUSION: By combining RT-PCR and CRISPPR-Cas12a gene editing technology, we successfully developed a new method for rapid detection and identification of SARS-CoV-2 Omicron BA.4/5 variants with a high sensitivity, specificity and reproducibility, which allows rapid detection and genotyping of SARS- CoV-2 variants and monitoring of the emerging variants and their dissemination.

Economic Evaluation of Nucleic Acid Testing for Screening of Blood Donations for Thalassemia Patients (ECONAT) in Western India.

Background: Transfusion Transmitted infections(TTI) are of significant concern for blood safety. The thalassemia patients who receive multiple transfusions are at an increased risk of TTIs and the Nucleic Acid Test (NAT ) has been advocated for safe blood. Though NAT can reduce the window period compared to serology, cost is a constraint. Methods: The thalassemia patient and NAT yield data from the centralized NAT lab in AIIMS Jodhpur was evaluated for cost-effectiveness using the Markov model. The incremental cost-effectiveness ratio (ICER) was calculated by dividing the difference between the cost for NAT and the cost of medical management of TTI-related complications by the product of the difference in utility value of a TTI health state with time and Gross National Income(GNI) per capita. Results: Out of the 48,762 samples tested by NAT, 43 samples were discriminated NAT yield all of which were reactive for Hepatitis B (NAT yield of 1:1134). There was no HCV and HIV NAT yield despite HCV being the most prevalent TTI in this population. The cost of this intervention was INR 5,85,14,400. The number of lifetime QALY saved was 1.38 years. The cost of medical management is INR 82,19,114. Therefore the ICER for intervention is INR 3,64,45,860 per QALY saved which is 274 times the GNI per capita of India. Conclusions: The provision of IDNAT-tested blood for thalassemia patients in Rajasthan state was not found to be cost-effective. Measures to bring down the cost or alternative options to increase blood safety should be explored.

The Significance of the Nucleic Acid Test (NAT) to Prevent Viral Contamination in Musculoskeletal Tissue Transplantation.

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.

Biocatalytic synthesis of 2'-deoxynucleotide 5'-triphosphates from bacterial genomic DNA: Proof of principle.

2'-deoxynucleoside 5'-triphosphates (dNTPs) are the building blocks of DNA and are key reagents which are incorporated by polymerase enzymes during nucleic acid amplification techniques, such as polymerase chain reaction (PCR). These techniques are of high importance, not only in molecular biology research, but also in molecular diagnostics. dNTPs are generally produced by a bottom-up technique which relies on synthesis or isolation of purified small molecules like deoxynucleosides. However, the disproportionately high cost of dNTPs in low- and middle-income countries (LMICs) and the requirement for cold chain storage during international shipping makes an adequate supply of these molecules challenging. To reduce supply chain dependency and promote domestic manufacturing in LMICs, a unique top-down biocatalytic synthesis method is described to produce dNTPs. Readily available bacterial genomic DNA provides a crude source material to generate dNTPs and is extracted directly from Escherichia coli (step 1). Nuclease enzymes are then used to digest the genomic DNA creating monophosphorylated deoxynucleotides (dNMPs) (step 2). Design and recombinant production and characterization of E. coli nucleotide kinases is presented to further phosphorylate the monophosphorylated products to generate dNTPs (step 3). Direct use of the in-house produced dNTPs in nucleic acid amplification is shown (step 4) and their successful use as reagents in the application of PCR, thereby providing proof of principle for the future development of recombinant nucleases and design of a recombinant solid-state bioreactor for on-demand dNTP production.

Wearable nucleic acid testing platform - A perspective on rapid self-diagnosis and surveillance of infectious diseases.

Wearable biosensors (WB) are currently attracting considerable interest for rapid detection and monitoring of biomarkers including metabolites, protein, and pathogen in bodily fluids (e.g., sweat, saliva, tears, and interstitial fluid). Another branch of WB termed wearable nucleic acid testing (NAT) is blossoming thanks to the development of microfluidic technology and isothermal nucleic acid amplification technique (iNAAT); however, there are only few reports on this. The wearable NAT is an emerging field of point-of-care (POC) diagnostics, and holds the promise for time-saving self-diagnosis, and evidence-based surveillance of infectious diseases in remote or low-resource settings. The use of wearable NAT can also be advanced to include molecular diagnosis, the identification of cancer biomarkers, genetic abnormalities, and other aspects. The wearable NAT provides the potential for evidence-based surveillance of infectious diseases when combined with internet connectivity and App software. To make the wearable NAT accessible to the end users, however, improvements must be made to the fabrication, cost, speed, sensitivity, specificity, sampling, iNAAT, analyzer, and a few other features. So, in this paper, we looked at the wearable NAT's most recent development, identified its difficulties, and defined its potential for managing infectious diseases quickly in the future. This is the wearable NAT review's first effort. We expect that this article will provide the concise resources needed to develop and deploy an efficient wearable NAT system.

The Significance of the Nucleic Acid Test (NAT) to Prevent Viral Contamination in Musculoskeletal Tissue Transplantation / A importância da realização do teste de ácidos nucleicos (NAT) para a prevenção de contaminação viral nos transplantes de tecidos musculoesqueléticos

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.

Easy detection of Prorocentrum donghaiense by polymerase chain reaction-nucleic acid chromatography strip.

In recent years, Prorocentrum donghaiense, as a dominant species, has ranked first in terms of cumulative number and area of algal blooms in the East China Sea. In this study, the D1-D2 region of the large ribosomal subunit of P. donghaiense was used as the target gene, and specific primers DH-FP/DH-RP were designed according to the species-specific region of the target gene. An easy, sensitive and visual detection method refered to as polymerase chain reaction-nucleic acid chromatography strip (PCR-NACS) was established for P. donghaiense. The optimized parameters of the PCR amplification system are as follows: primer concentration, 0.15 µM; annealing temperature, 62 °C; and Mg2+ concentration, 1.5 mM. The specificity test showed that PCR-NACS was exlusively specific for the detection of the target algae. The sensitivity test show that the lowest detection limit (LDL) of PCR-NACS was 2.7 × 10-2 ng·µL-1 for genomic DNA and 3.58 × 102 copies·µL-1 for plasmid DNA, respectively. The tests using both genomic DNA and plasmid DNA as templates showed that the sensitivity of PCR-NACS was 10 times higher than that of ordinary PCR. The stability test showed that the interfering algal species did not affect the detection of the target algae by PCR-NACS. In addition, the test with simulated natural samples containing target algae showed that the LDL of PCR-NACS could reach 1.27 × 101 cells·mL-1. In summary, the PCR-NACS established in this study may provide a new method for easy identification of P. donghaiense in natural water samples.