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1.
Mol Genet Metab ; 142(1): 108361, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38442492

RESUMO

INTRODUCTION: Phenylketonuria (PKU) requires regular phenylalanine monitoring to ensure optimal outcome. However, home sampling methods used for monitoring suffer high pre-analytical variability, inter-laboratory variability and turn-around-times, highlighting the need for alternative methods of home sampling or monitoring. METHODS: A survey was distributed through email and social media to (parents of) PKU patients and professionals working in inherited metabolic diseases in Denmark, The Netherlands, and United Kingdom regarding satisfaction with current home sampling methods and expectations for future point-of-care testing (POCT). RESULTS: 210 parents, 156 patients and 95 professionals completed the survey. Countries, and parents and patients were analysed together, in absence of significant group differences for most questions. Important results are: 1) Many patients take less home samples than advised. 2) The majority of (parents of) PKU patients are (somewhat) dissatisfied with their home sampling method, especially with turn-around-times (3-5 days). 3) 37% of professionals are dissatisfied with their home sampling method and 45% with the turn-around-times. 4) All responders are positive towards developments for POCT: 97% (n = 332) of (parents of) patients is willing to use a POC-device and 76% (n = 61) of professionals would recommend their patients to use a POC-device. 5) Concerns from all participants for future POC-devices are costs/reimbursements and accuracy, and to professionals specifically, accessibility to results, over-testing, patient anxiety, and patients adjusting their diet without consultation. CONCLUSION: The PKU community is (somewhat) dissatisfied with current home sampling methods, highlighting the need for alternatives of Phe monitoring. POCT might be such an alternative and the community is eager for its arrival.


Assuntos
Pais , Fenilcetonúrias , Testes Imediatos , Humanos , Fenilcetonúrias/diagnóstico , Fenilcetonúrias/sangue , Masculino , Feminino , Inquéritos e Questionários , Pais/psicologia , Coleta de Amostras Sanguíneas , Reino Unido , Países Baixos , Adulto , Satisfação do Paciente , Fenilalanina/sangue , Dinamarca , Criança , Adolescente
2.
Clin Chem Lab Med ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38726766

RESUMO

OBJECTIVES: This study aimed to evaluate discrepancies in potassium measurements between point-of-care testing (POCT) and central laboratory (CL) methods, focusing on the impact of hemolysis on these measurements and its impact in the clinical practice in the emergency department (ED). METHODS: A retrospective analysis was conducted using data from three European university hospitals: Technische Universitat Munchen (Germany), Hospital Universitario La Paz (Spain), and Erasmus University Medical Center (The Netherlands). The study compared POCT potassium measurements in EDs with CL measurements. Data normalization was performed in categories for potassium levels (kalemia) and hemolysis. The severity of discrepancies between POCT and CL potassium measurements was assessed using the reference change value (RCV). RESULTS: The study identified significant discrepancies in potassium between POCT and CL methods. In comparing POCT normo- and mild hypokalemia against CL results, differences of -4.20 % and +4.88 % were noted respectively. The largest variance in the CL was a +4.14 % difference in the mild hyperkalemia category. Additionally, the RCV was calculated to quantify the severity of discrepancies between paired potassium measurements from POCT and CL methods. The overall hemolysis characteristics, as defined by the hemolysis gradient, showed considerable variation between the testing sites, significantly affecting the reliability of potassium measurements in POCT. CONCLUSIONS: The study highlighted the challenges in achieving consistent potassium measurement results between POCT and CL methods, particularly in the presence of hemolysis. It emphasised the need for integrated hemolysis detection systems in future blood gas analysis devices to minimise discrepancies and ensure accurate POCT results.

3.
Clin Chem Lab Med ; 61(9): 1572-1579, 2023 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-37267483

RESUMO

The International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) Committee on Point-of-Care Testing (C-POCT) supports the use of point-of-care testing (POCT) outside of the hospital setting performed by healthcare professionals without formal laboratory education because of its numerous benefits. However, these benefits are associated with risks that must be managed, to ensure the provision of reliable test results and minimize harm to the patient. Healthcare professionals, local regulatory bodies, accredited laboratories as well as manufacturers should actively be engaged in education, oversight and advice to ensure that the healthcare professional selects the appropriate equipment and is able to analyze, troubleshoot and correctly interpret the point-of-care (POC) test results.


Assuntos
Hospitais , Testes Imediatos , Humanos , Consenso , Laboratórios , Atenção à Saúde , Sistemas Automatizados de Assistência Junto ao Leito
4.
Sens Actuators B Chem ; 379: 133244, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36589905

RESUMO

Nucleic acid amplification is crucial for disease diagnosis, especially lethal infectious diseases such as COVID-19. Compared with PCR, isothermal amplification methods are advantageous for point-of-care testing (POCT). However, complicated primer design limits their application in detecting some short targets or sequences with abnormal GC content. Herein, we developed a novel linear displacement isothermal amplification (LDIA) method using two pairs of conventional primers and Bacillus stearothermophilus (Bst) DNA polymerase, and reactions could be accelerated by adding an extra primer. Pseudorabies virus gE (high GC content) and Salmonella fimW (low GC content) genes were used to evaluate the LDIA assay. Using strand displacement (SD) probes, a LDIA-SD method was developed to realize probe-based specific detection. Additionally, we incorporated a nucleic acid-free extraction step and a pocket-sized device to realize POCT applications of the LDIA-SD method. The LDIA-SD method has advantages including facile primer design, high sensitivity and specificity, and applicability for POCT, especially for amplification of complex sequences and detection of infectious diseases.

5.
Am J Emerg Med ; 71: 139-143, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37392513

RESUMO

BACKGROUND: Non-ST-segment elevation myocardial infarction (NSTEMI) is a common form of acute myocardial infarction and rapid and accurate diagnosis is crucial for timely treatment. Current guidelines recommend using high-sensitivity cardiac troponin (hs-cTn) assays to determine circulating cTnI or cTnT levels. While the accuracy of the 0 h/1 h algorithm for diagnosing NSTEMI in different regions and patient populations remains controversial. Additionally, point-of-care testing (POCT) cTn assays have the potential to provide troponin readings to physicians within 15 min, but their accuracy in diagnosing NSTEMI in the emergency department (ED) requires further investigation. METHODS: A single-center prospective observational cohort study was conducted at Shaanxi Provincial People's Hospital to assess the analytical and diagnostic performance of the laboratory-based Roche Modular E170 hs-cTnT using the 0 h/1 h algorithm with Radiometer AQT90-flex POCT cTnT assay in undifferentiated chest pain patients presenting to the ED. Whole-blood samples were collected and hs-cTnT and POCT cTnI were measured simultaneously at baseline and after 1 h. RESULTS: The study results showed that the POCT cTnT assay using the 0 h/1 h algorithm had comparable diagnostic accuracy to the laboratory-based Roche Modular E170 hs-cTnT assay in diagnosing NSTEMI in patients with chest pain. CONCLUSION: The laboratory-based Roche Modular E170 hs-cTnT using the 0 h/1 h algorithm is reliable and accurate method for diagnosing NSTEMI in undifferentiated chest pain patients presenting to the ED. POCT cTnT assay has comparable diagnostic accuracy to the hs-cTnT assay and its rapid turnaround time makes it a valuable tool in expediting the diagnostic workup of chest pain patients.


Assuntos
Infarto do Miocárdio sem Supradesnível do Segmento ST , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Infarto do Miocárdio sem Supradesnível do Segmento ST/diagnóstico , Estudos Prospectivos , Dor no Peito/diagnóstico , Dor no Peito/etiologia , Troponina T , Troponina I , Algoritmos , Serviço Hospitalar de Emergência , Biomarcadores
6.
J Fish Dis ; 46(2): 137-146, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36336976

RESUMO

Decapod iridescent virus 1 (DIV1), White spot syndrome virus (WSSV), and Enterocytozoon hepatopenaei (EHP) pose serious threats to the shrimp farming. To date, early detection remains an important way to control the occurrence and diffusion of these pathogens. Here, we developed for the first time, a loop-mediated isothermal amplification (LAMP)-based microfluidic chip detection system, which could detect DIV1, WSSV, and EHP simultaneously. The limits of detection (LoD) of the system were 10 copies/reaction for EHP and DIV1, and 102 copies/reaction for WSSV. The entire detection procedure could be completed rapidly in 40 min at 63°C with 100% specificity and had no cross-reaction with other common shrimp pathogens. This newly established method was further validated using 94 Penaeus vannamei clinical samples, which were comparable to a typical qPCR assay and revealed good stability and reproducibility. These results illustrate that this LAMP microfluidic chip detection system allows rapid triplex pathogen analysis and could satisfy the demands of the field and routine diagnoses in aquaculture.


Assuntos
Doenças dos Peixes , Penaeidae , Viroses , Animais , Microfluídica , Técnicas de Amplificação de Ácido Nucleico/veterinária , Técnicas de Amplificação de Ácido Nucleico/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
Sensors (Basel) ; 23(18)2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37765943

RESUMO

This Editorial provides summaries and an overview of research and review articles published in the Sensors journal, volumes 21 (2021), 22 (2022), and 23 (2023), within the biomedical Special Issue "Portable Electronic-Nose Devices for Noninvasive Early Disease Detection", which focused on recent sensors, biosensors, and clinical instruments developed for noninvasive early detection and diagnosis of human and animal diseases. The ten articles published in this Special Issue provide new information associated with recent electronic-nose (e-nose) and related volatile organic compound (VOC)-detection technologies developed to improve the effectiveness and efficiency of diagnostic methodologies for early disease detection prior to symptom development. For review purposes, the summarized articles were placed into three broad groupings or topic areas, including veterinary-wildlife pathology, human clinical pathology, and the detection of dietary effects on VOC emissions. These specified categories were used to define sectional headings devoted to related research studies with a commonality based on a particular disease being investigated or type of analytical instrument used in analyses.


Assuntos
Nariz Eletrônico , Compostos Orgânicos Voláteis , Animais , Humanos , Diagnóstico Precoce , Animais Selvagens , Eletrônica
8.
Biomed Microdevices ; 24(4): 38, 2022 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-36326901

RESUMO

An automated microfluidic system with functionalized beads has been developed for multiplexed TORCH detection at point-of-care testing. A concise microfluidic chip consisting of a one-dimensional beads array is developed to simultaneously detect TOX, RUB, CMV, HSV-I and HSV-II respectively with five functionalized beads. A compact liquid handling module has been developed to automate the sandwiched chemiluminescence immunoassay within the one-dimensional beads array of the microfluidic chip. A precise ram pump is adopted to not only add reagent into the microfluidic chip from outside, but also facilitate elaborate fluid control inside the microfluidic chip for improved performance. A large-size waste chamber with a liquid-absorbing sponge holds the waste reagent within the microfluidic chip to prevent backflow. The one-dimensional beads array is heated from double-sides at 37 ℃ for sensitive detection with reduced time. A sensitive CMOS camera is adopted to take chemiluminescence image from the one-dimensional beads array, and a custom processing algorithm is adopted to analyze the image. For each serum sample, five different infections can be simultaneously detected with the automated microfluidic system. Experimental results show that efficient, sensitive, and accurate multiplexed TORCH detection can be conveniently achieved with the integrated microfluidic system.


Assuntos
Técnicas Analíticas Microfluídicas , Microfluídica , Animais , Masculino , Ovinos , Microfluídica/métodos , Imunoensaio/métodos , Testes Imediatos , Medições Luminescentes/métodos , Análise de Sequência com Séries de Oligonucleotídeos , Técnicas Analíticas Microfluídicas/métodos , Sistemas Automatizados de Assistência Junto ao Leito
9.
Biotechnol Bioeng ; 119(2): 347-360, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34859425

RESUMO

Nanomaterials, especially superparamagnetic nanomaterials, have recently played essential roles in point-of-care testing due to their intrinsic magnetic, electrochemical, and optical properties. The inherent superparamagnetism of magnetic nanoparticles makes them highly sensitive for quantitative detection. Among the various magnetic detection technologies, frequency mixing technology (FMT) technology is an emerging detection technique in the nanomedical field. FMT sensors have high potential for development in the field of biomedical quantitative detection due to their simple structure, and they are not limited to the materials used. In particular, they can be applied for large-scale disease screening, early tumor marker detection, and low-dose drug detection. This review summarizes the principles of FMT and recent advances in the fields of immunoadsorption, lateral flow assay detection, magnetic imaging, and magnetic nanoparticles recognition. The advantages and limitations of FMT sensors for robust, ultrasensitive biosensing are highlighted. Finally, the future requirements and challenges in the development of this technology are described. This review provides further insights for researchers to inspire the future development of FMT by integration into biosensing and devices with a broad field of applications in analytical sensing and clinical usage.


Assuntos
Tecnologia Biomédica/métodos , Radiação Eletromagnética , Nanopartículas de Magnetita , Testes Imediatos , Animais , Técnicas de Laboratório Clínico , Humanos , Imunoensaio , Coelhos
10.
Clin Chem Lab Med ; 60(8): 1186-1201, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35607775

RESUMO

OBJECTIVES: Proposal of a risk analysis model to diminish negative impact on patient care by preanalytical errors in blood gas analysis (BGA). METHODS: Here we designed a Failure Mode and Effects Analysis (FMEA) risk assessment template for BGA, based on literature references and expertise of an international team of laboratory and clinical health care professionals. RESULTS: The FMEA identifies pre-analytical process steps, errors that may occur whilst performing BGA (potential failure mode), possible consequences (potential failure effect) and preventive/corrective actions (current controls). Probability of failure occurrence (OCC), severity of failure (SEV) and probability of failure detection (DET) are scored per potential failure mode. OCC and DET depend on test setting and patient population e.g., they differ in primary community health centres as compared to secondary community hospitals and third line university or specialized hospitals. OCC and DET also differ between stand-alone and networked instruments, manual and automated patient identification, and whether results are automatically transmitted to the patient's electronic health record. The risk priority number (RPN = SEV × OCC × DET) can be applied to determine the sequence in which risks are addressed. RPN can be recalculated after implementing changes to decrease OCC and/or increase DET. Key performance indicators are also proposed to evaluate changes. CONCLUSIONS: This FMEA model will help health care professionals manage and minimize the risk of preanalytical errors in BGA.


Assuntos
Análise do Modo e do Efeito de Falhas na Assistência à Saúde , Humanos , Fase Pré-Analítica , Probabilidade , Medição de Risco
11.
Anal Bioanal Chem ; 414(10): 3177-3186, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35044487

RESUMO

The degree of detrimental effects inflicted on mankind by the COVID-19 pandemic increased the need to develop ASSURED (Affordable, Sensitive, Specific, User-friendly, Rapid and Robust, Equipment-free, and Deliverable) POCT (point of care testing) to overcome the current and any future pandemics. Much effort in research and development is currently advancing the progress to overcome the diagnostic pressure built up by emerging new pathogens. LAMP (loop-mediated isothermal amplification) is a well-researched isothermal technique for specific nucleic acid amplification which can be combined with a highly sensitive immunochromatographic readout via lateral flow assays (LFA). Here we discuss LAMP-LFA robustness, sensitivity, and specificity for SARS-CoV-2 N-gene detection in cDNA and clinical swab-extracted RNA samples. The LFA readout is designed to produce highly specific results by incorporation of biotin and FITC labels to 11-dUTP and LF (loop forming forward) primer, respectively. The LAMP-LFA assay was established using cDNA for N-gene with an accuracy of 95.65%. To validate the study, 82 SARS-CoV-2-positive RNA samples were tested. Reverse transcriptase (RT)-LAMP-LFA was positive for the RNA samples with an accuracy of 81.66%; SARS-CoV-2 viral RNA was detected by RT-LAMP-LFA for as low as CT-33. Our method reduced the detection time to 15 min and indicates therefore that RT-LAMP in combination with LFA represents a promising nucleic acid biosensing POCT platform that combines with smartphone based semi-quantitative data analysis.


Assuntos
COVID-19 , Ácidos Nucleicos , Biotina , COVID-19/diagnóstico , Humanos , Pandemias , SARS-CoV-2/genética
12.
BMC Vet Res ; 18(1): 369, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36221092

RESUMO

BACKGROUND: Swine acute diarrhea syndrome coronavirus (SADS-CoV) causes acute vomiting and diarrhea in piglets, leading to significant financial losses for the pig industry. Recombinase polymerase amplification (RPA) is a rapid nucleic acid amplification technology used under constant temperature conditions. The study established a real-time reverse transcription (RT)-RPA assay for early diagnosis of SADS-CoV.  RESULTS: The detection limit of the real-time RT-RPA was 74 copies/µL of SADS-CoV genomic standard recombinant plasmid in 95% of cases. The assay was performed in less than 30 min and no cross-reactions were observed with eight other common viruses that affect swine, including classical swine fever virus (CSFV), porcine reproductive and respiratory syndrome virus (PRRSV), pseudo rabies virus (PRV), swine influenza virus (SIV), seneca valley virus (SVA), transmissible gastroenteritis virus (TGEV), porcine epidemic diarrhea virus (PEDV) and porcine deltacoronavirus (PDCoV). The coefficient of variation (C.V.) values of the two standards dilutions and three positive clinical sample ranged from 2.95% to 4.71%. A total of 72 clinical fecal samples from swine with diarrheal symptoms were analyzed with the developed RT-RPA and quantitative RT-PCR. There was 98.61% agreement between the RT-RPA and the quantitative real-time PCR results. CONCLUSIONS: These results indicated that the developed RT-RPA assay had good specificity, sensitivity, stability and repeatability. The study successfully established a broadly reactive RT-RPA assay for SADS-CoV detection.


Assuntos
Alphacoronavirus , Infecções por Coronavirus , Ácidos Nucleicos , Doenças dos Suínos , Alphacoronavirus/genética , Animais , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/veterinária , Diarreia/diagnóstico , Diarreia/veterinária , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Recombinases , Sensibilidade e Especificidade , Suínos , Doenças dos Suínos/diagnóstico
13.
Luminescence ; 37(2): 357-365, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34931738

RESUMO

There is a growing demand to realize low-cost miniaturized point-of-care testing diagnostic devices capable of performing many analytical assays. To fabricate such devices, three-dimensional printing (3DP)-based fabrication techniques provide a turnkey approach with marked precision and accuracy. Here, a 3DP fabrication technique was successfully utilized to fabricate closed bipolar electrode-based electrochemiluminescence (ECL) devices using conductive graphene filament. Furthermore, using these ECL devices, Ru(bpy)3 2+ /TPrA- and luminol/H2 O2 -based electrochemistry was leveraged to sense dopamine and choline respectively. For ECL signal capture, two distinct approaches were used, first a smartphone-based miniaturized platform and the second with a photomultiplier tube embedded with the internet of things technology. Choline sensing led to a linear range 5-700 µM and 30-700 µM with a limit of detection (LOD) of 1.25 µM (R2 = 0.98, N = 3) and 3.27 µM (R2 = 0.97, N = 3). Furthermore, dopamine sensing was achieved in a linear range 0.5-100 µM with an LOD = 2 µM (R2 = 0.99, N = 3) and LOD = 0.33 µM (R2 = 0.98, N = 3). Overall, the fabricated devices have the potential to be utilized effectively in real-time applications such as point-of-care testing.


Assuntos
Técnicas Biossensoriais , Internet das Coisas , Colina , Dopamina , Técnicas Eletroquímicas , Eletrodos , Medições Luminescentes , Impressão Tridimensional , Smartphone
14.
Sensors (Basel) ; 22(22)2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36433221

RESUMO

Real-time Polymerase Chain Reaction (RT-PCR), a molecular diagnostic technology, is spotlighted as one of the quickest and fastest diagnostic methods for the actual coronavirus (SARS-CoV-2). However, the fluorescent label-based technology of the RT-PCR technique requires expensive equipment and a sample pretreatment process for analysis. Therefore, this paper proposes a biochip based on Electrochemical Impedance Spectroscopy (EIS). In this paper, it was possible to see the change according to the concentration by measuring the impedance with a chip made of two electrodes with different shapes of sample DNA.


Assuntos
COVID-19 , Amplificação de Genes , Humanos , RNA Viral/análise , SARS-CoV-2/genética , COVID-19/diagnóstico , Eletrodos
15.
Compr Rev Food Sci Food Saf ; 21(2): 1868-1912, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35194932

RESUMO

Diverse chemicals and some physical phenomena recently introduced in nanotechnology have enabled scientists to develop useful devices in the field of food sciences. Concerning such developments, detecting foodborne pathogenic bacteria is now an important issue. These kinds of bacteria species have demonstrated severe health effects after consuming foods and high mortality related to acute cases. The most leading path of intoxication and infection has been through food matrices. Hence, quick recognition of foodborne bacteria agents at low concentrations has been required in current diagnostics. Lateral flow assays (LFAs) are one of the urgent and prevalently applied quick recognition methods that have been settled for recognizing diverse types of analytes. Thus, the present review has stressed on latest developments in LFAs-based platforms to detect various foodborne pathogenic bacteria such as Salmonella, Listeria, Escherichia coli, Brucella, Shigella, Staphylococcus aureus, Clostridium botulinum, and Vibrio cholera. Proper prominence has been given on exactly how the labels, detection elements, or procedures have affected recent developments in the evaluation of diverse bacteria using LFAs. Additionally, the modifications in assays specificity and sensitivity consistent with applied food processing techniques have been discussed. Finally, a conclusion has been drawn for highlighting the main challenges confronted through this method and offered a view and insight of thoughts for its further development in the future.


Assuntos
Contaminação de Alimentos , Sistemas Automatizados de Assistência Junto ao Leito , Bactérias , Contaminação de Alimentos/análise
16.
Indian J Clin Biochem ; 37(2): 199-205, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35463101

RESUMO

Glucometer is the most commonly used POCT device and guides monitoring of blood glucose level in both clinical settings and outside. Inaccurate glucometer readings resulting in erroneous therapeutic intervention has critical consequences on patient care. Regulatory guidelines for performance evaluation of glucometers are not available in many countries. A robust program implemented by the hospital is essential to ensure accuracy and precision of glucometers to produce optimal results. The objective of this study was to design a quality assurance program for the evaluation of glucometers in a high volume tertiary care referral hospital and evaluate the results from July'18 to July'19. Seventy three glucometers used across the hospital were subjected to Internal Quality Control checks and Proficiency Testing performed once a month and every 3 months respectively. The results were reviewed and plotted on a Bland Altman Graph. Clarke Error Grid Analysis was done to evaluate the clinical significance of inaccuracies in the measurement of blood glucose concentration as per ISO 15197: 2013. Eight devices were identified as unacceptable by ISO standards and replaced subsequently. 96.83% and 3.17% of the values were in Zone A and B of Clarke Error Grid Analysis. The study complied with the standard which requires that 99% of the values fall within zones A and B. The review of the program after one year and its ability to identify defective glucometers has validated the efficacy of the model. The method used may be suggested as a prototype for quality management of glucometers in a clinical setting.

17.
Artigo em Inglês | MEDLINE | ID: mdl-33361302

RESUMO

Molecular genotyping holds tremendous potential to detect antimalarial drug resistance (ADR) related to single nucleotide polymorphisms (SNPs). However, it relies on the use of complicated procedures and expensive instruments. Thus, rapid point-of-care testing (POCT) molecular tools are urgently needed for field survey and clinical use. Herein, a POCT platform consisting of multiple-allele-specific PCR (AS-PCR) and a gold nanoparticle (AuNP)-based lateral flow biosensor was designed and developed for SNP detection of the Plasmodium falciparum dihydrofolate reductase (pfdhfr) gene related to pyrimethamine resistance. The multiple-AS-PCR utilized 3' terminal artificial antepenultimate mismatch and double phosphorothioate-modified allele-specific primers. The duplex PCR amplicons with 5' terminal labeled with biotin and digoxin are recognized by streptavidin (SA)-AuNPs on the conjugate pad and then captured by anti-digoxin antibody through immunoreactions on the test line to produce a golden red line for detection. The system was applied to analyze SNPs in Pfdhfr N51I, C59R, and S108N of 98 clinical isolates from uncomplicated P. falciparum malaria patients. Compared with the results from nested PCR followed by Sanger DNA sequencing, the sensitivity was 97.96% (96/98) for N51I, C59R, and S108N. For specificity, the values were 100% (98/98), 95.92% (94/98), and 100% (98/98) for N51I, C59R, and S108N, respectively. The limit of detection is approximately 200 fg/µl for plasmid DNA as the template and 100 parasites/µl for blood filter paper. The established platform not only offers a powerful tool for molecular surveillance of ADR but also is easily extended to interrelated SNP profiles for infectious diseases and genetic diseases.


Assuntos
Antimaláricos , Técnicas Biossensoriais , Malária Falciparum , Nanopartículas Metálicas , Alelos , Antimaláricos/farmacologia , Primers do DNA , Resistência a Medicamentos/genética , Ouro , Humanos , Malária Falciparum/tratamento farmacológico , Plasmodium falciparum/genética , Reação em Cadeia da Polimerase , Pirimetamina/uso terapêutico , Sulfadoxina/uso terapêutico , Tetra-Hidrofolato Desidrogenase/genética
18.
Trends Analyt Chem ; 143: 116377, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34188341

RESUMO

PCR has been widely used in different fields including molecular biology, pathogen detection, medical diagnosis, food detection and etc. However, the difficulty of promoting PCR in on-site point-of-care testing reflects on challenges relative to its speed, convenience, complexity, and even cost. With the emerging state-of-art of microfluidics, rapid PCR can be achieved with more flexible ways in micro-reactors. PCR plays a critical role in the detection of SARS-CoV-2. Under this special background of COVID-19 pandemic, this review focuses on the latest rapid microfluidic PCR. Rapid PCR is concluded in two main features, including the reactor (type, size, material) and the implementation of thermal cycling. Especially, the compromise between speed and sensitivity with microfluidic PCR is explored based on the system ratio of (thermal cycling time)/(reactor size). Representative applications about the detection of pathogens and SARS-CoV-2 viruses based on rapid PCR or other isothermal amplification are discussed as well.

19.
Eur J Clin Microbiol Infect Dis ; 40(8): 1721-1726, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33742322

RESUMO

SARS-CoV-2 antigen tests used at the point-of-care, such as the Abbott Panbio, have great potential to help combat the COVID-19 pandemic. The Panbio is Health Canada approved for the detection of SARS-CoV-2 in symptomatic individuals within the first 7 days of COVID-19 symptom onset(s). Symptomatic adults recently diagnosed with COVID-19 in the community were recruited into the study. Paired nasopharyngeal (NP), throat, and saliva swabs were collected, with one paired swab tested immediately with the Panbio, and the other transported in universal transport media and tested using real-time reverse-transcriptase polymerase chain reaction (RT-PCR). We also prospectively evaluated results from assessment centers within the community. For those individuals, an NP swab was collected for Panbio testing and paired with RT-PCR results from parallel NP or throat swabs. One hundred and forty-five individuals were included in the study. Collection of throat and saliva was stopped early due to poorer performance (throat sensitivity 57.7%, n=61, and saliva sensitivity 2.6%, n=41). NP swab sensitivity was 87.7% [n=145, 95% confidence interval (CI) 81.0-92.7%]. There were 1641 symptomatic individuals tested by Panbio in assessment centers with 268/1641 (16.3%) positive for SARS-CoV-2. There were 37 false negatives and 2 false positives, corresponding to a sensitivity and specificity of 86.1% [95% CI 81.3-90.0%] and 99.9% [95% CI 99.5-100.0%], respectively. The Panbio test reliably detects most cases of SARS-CoV-2 from adults in the community setting presenting within 7 days of symptom onset using nasopharyngeal swabs. Throat and saliva swabs are not reliable specimens for the Panbio.


Assuntos
Teste para COVID-19 , COVID-19/diagnóstico , Nasofaringe/virologia , Faringe/virologia , Saliva/virologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Canadá , Reações Falso-Negativas , Reações Falso-Positivas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Manejo de Espécimes
20.
Clin Chem Lab Med ; 59(4): 765-774, 2021 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-33128524

RESUMO

OBJECTIVES: Point-of-care (POC) analyzers are playing an increasingly important role in diabetes management but it is essential that we know the performance of these analyzers in order to make appropriate clinical decisions. Whilst there is a growing body of evidence around the more well-known analyzers, there are many 'new kids on the block' with new features, such as displaying the presence of potential Hb-variants, which do not yet have a proven track record. METHODS: The study is a comprehensive analytical and usability study of six POC analyzers for HbA1c using Clinical and Laboratory Standards Institute (CLSI) protocols, international quality targets and certified International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) and National Glycohemoglobin Standardization Program (NGSP) Secondary Reference Measurement Procedures (SRMP). The study includes precision (EP-5 and EP-15), trueness (EP-9), linearity (EP-6), sample commutability (fresh, frozen and lyophilized), interference of Hb-variants (fresh and frozen samples). RESULTS: Only two of the six analyzers performed to acceptable levels over the range of performance criteria. Hb-variant interference, imprecision or variability between lot numbers are still poor in four of the analyzers. CONCLUSIONS: This unique and comprehensive study shows that out of six POC analyzers studied only two (The Lab 001 and Cobas B101) met international quality criteria (IFCC and NGSP), two (A1Care and Innovastar) were borderline and two (QuikReadgo and Allegro) were unacceptable. It is essential that the scientific and clinical community are equipped with this knowledge in order to make sound decisions on the use of these analyzers.


Assuntos
Testes Hematológicos , Sistemas Automatizados de Assistência Junto ao Leito , Hemoglobinas Glicadas/análise , Hemoglobina Falciforme , Humanos , Padrões de Referência , Reprodutibilidade dos Testes
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