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1.
Anal Bioanal Chem ; 416(6): 1443-1455, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38228897

RESUMO

This study presents a groundbreaking approach for the early detection of chronic kidney disease (CKD) and other urological disorders through an image-label-free, multi-dipstick identification method, eliminating the need for complex machinery, label libraries, or preset coordinates. Our research successfully identified reaction pads on 187 multi-dipsticks, each with 11 pads, leveraging machine learning algorithms trained on human urine data. This technique aims to surpass traditional colourimetric methods and concentration-colour curve fitting, offering more robust and precise community screening and home monitoring capabilities. The developed algorithms enhance the generalizability of machine learning models by extracting primary colours and correcting urine colours on each reaction pad. This method's cost-effectiveness and portability are significant, as it requires no additional equipment beyond a standard smartphone. The system's performance rivals professional medical equipment without auxiliary lighting or flash under regular indoor light conditions, effectively managing false positives and negatives across various categories with remarkable accuracy. In a controlled experimental setting, we found that random forest algorithms, based on a Bagging strategy and applied in the HSV colour space, showed optimal results in smartphone-assisted urinalysis. This study also introduces a novel urine colour correction method, significantly improving machine learning model performance. Additionally, ISO parameters were identified as crucial factors influencing the accuracy of smartphone-based urinalysis in the absence of additional lighting or optical configurations, highlighting the potential of this technology in low-resource settings.


Assuntos
Insuficiência Renal Crônica , Smartphone , Humanos , Urinálise/métodos , Algoritmos , Aprendizado de Máquina
2.
Appl Microbiol Biotechnol ; 108(1): 414, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38985204

RESUMO

Airborne animal viral pathogens can rapidly spread and become a global threat, resulting in substantial socioeconomic and health consequences. To prevent and control potential epidemic outbreaks, accurate, fast, and affordable point-of-care (POC) tests are essential. As a proof-of-concept, we have developed a molecular system based on the loop-mediated isothermal amplification (LAMP) technique for avian metapneumovirus (aMPV) detection, an airborne communicable agent mainly infecting turkeys and chickens. For this purpose, a colorimetric system was obtained by coupling the LAMP technique with specific DNA-functionalized AuNPs (gold nanoparticles). The system was validated using 50 different samples (pharyngeal swabs and tracheal tissue) collected from aMPV-infected and non-infected chickens and turkeys. Viral detection can be achieved in about 60 min with the naked eye, with 100% specificity and 87.88% sensitivity for aMPV. In summary, this novel molecular detection system allows suitable virus testing in the field, with accuracy and limit of detection (LOD) values highly close to qRT-PCR-based diagnosis. Furthermore, this system can be easily scalable to a platform for the detection of other viruses, addressing the current gap in the availability of POC tests for viral detection in poultry farming. KEY POINTS: •aMPV diagnosis using RT-LAMP is achieved with high sensitivity and specificity. •Fifty field samples have been visualized using DNA-nanoprobe validation. •The developed system is a reliable, fast, and cost-effective option for POCT.


Assuntos
Galinhas , Ouro , Metapneumovirus , Técnicas de Diagnóstico Molecular , Técnicas de Amplificação de Ácido Nucleico , Infecções por Paramyxoviridae , Doenças das Aves Domésticas , Sensibilidade e Especificidade , Metapneumovirus/genética , Metapneumovirus/isolamento & purificação , Animais , Técnicas de Amplificação de Ácido Nucleico/métodos , Técnicas de Amplificação de Ácido Nucleico/economia , Galinhas/virologia , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Diagnóstico Molecular/economia , Infecções por Paramyxoviridae/diagnóstico , Infecções por Paramyxoviridae/veterinária , Infecções por Paramyxoviridae/virologia , Doenças das Aves Domésticas/virologia , Doenças das Aves Domésticas/diagnóstico , Ouro/química , Perus , Nanopartículas Metálicas/química , Limite de Detecção , Colorimetria/métodos , DNA Viral/genética
3.
Eur J Clin Microbiol Infect Dis ; 40(9): 1975-1981, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34021840

RESUMO

The RT-qPCR in respiratory specimens is the gold standard for diagnosing acute COVID-19 infections. However, this test takes considerable time before test results become available, thereby delaying patients from being diagnosed, treated, and isolated immediately. Rapid antigen tests could overcome this problem. In the first study, clinical performances of five rapid antigen tests were compared to RT-qPCR in upper respiratory specimens from 40 patients with positive and 40 with negative RTq-PCR results. In the second study, the rapid antigen test with one of the best test characteristics (Romed) was evaluated in a large prospective collection of upper respiratory specimens from 900 different COVID-19-suspected patients (300 emergency room patients, 300 nursing home patients, and 300 health care workers). Test specificities ranged from 87.5 to 100.0%, and test sensitivities from 55.0 to 80.0%. The clinical specificity of the Romed test was 99.8% (95% CI 98.9-100). Overall clinical sensitivity in the study population was 73.3% (95% CI 67.9-78.2), whereas sensitivity in the different patient groups varied from 65.3 to 86.7%. Sensitivity was 83.0 to 86.7% in patients with short duration of symptoms. In a population with a COVID-19 prevalence of 1%, the negative predictive value in all patients was 99.7%. There is a large variability in diagnostic performance between rapid antigen tests. The Romed rapid antigen test showed a good clinical performance in patients with high viral loads (RT-qPCR cycle threshold ≤30), which makes this antigen test suitable for rapid identification of COVID-19-infected health care workers and patients.


Assuntos
Teste Sorológico para COVID-19/métodos , COVID-19/diagnóstico , Testes Imediatos , SARS-CoV-2/imunologia , Antígenos Virais/análise , COVID-19/virologia , Humanos , Estudos Prospectivos , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , Sensibilidade e Especificidade
4.
Indian J Med Res ; 152(4): 378-385, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33380702

RESUMO

BACKGROUND & OBJECTIVES: : Early case detection is essential to interrupt transmission and to prevent further spread of tuberculosis (TB) in high endemic settings. Nucleic acid amplification tests (NAATs) with visual read-outs are ideal as point-of-care tests. Truenat™ MTB is an indigenous chip-based NAAT for detection of Mycobacterium tuberculosis, which involves extraction of DNA and real-time polymerase chain reaction (PCR) using portable, automated, battery-operated instruments. The current multicentric study was aimed to evaluate Truenat for detection of MTB in sputum samples obtained from patients with presumptive pulmonary TB with reference to culture as gold standard and Xpert as a comparator. METHODS: : The study was conducted at four sites, namely ICMR-National Institute for Research in Tuberculosis, Chennai; All India Institute of Medical Sciences, New Delhi; ICMR-National JALMA Institute for Leprosy and Other Mycobacterial Diseases, Agra; and National Institute of TB and Respiratory Diseases, New Delhi. Patients suspected to have TB were screened for eligibility. Two sputum samples were collected from each patient. Tests included smear, Xpert and Truenat directly from the sputum sample and culture by Lowenstein-Jensen (L-J) medium and MGIT960 from decontaminated pellets. Sample used for Truenat assay was coded. Resolution of Truenat false positives was done using an in-house PCR with TRC4 primers. RESULTS: : The study enrolled 2419 presumptive TB patients after screening 2465 patients, and 3541 sputum samples were collected from the enrolled patients. Results of 2623 samples were available for analysis. Truenat showed a positivity rate of 48.5 per cent as compared to 37.0 per cent by Xpert. The sensitivities of Truenat and Xpert were was 88.3 and 79.7 per cent, respectively in comparison with culture. INTERPRETATION & CONCLUSIONS: : Truenat MTB identified more positives among culture-confirmed samples than Xpert and had higher sensitivity. In addition, other advantageous operational features of Truenat MTB were identified which would be useful in field settings.


Assuntos
Mycobacterium tuberculosis , Tuberculose Pulmonar , Humanos , Índia , Mycobacterium tuberculosis/genética , Padrões de Referência , Sensibilidade e Especificidade , Escarro , Tuberculose Pulmonar/diagnóstico
5.
Viruses ; 16(4)2024 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-38675954

RESUMO

The first point-of-care (PoC) test (v-RetroFel®; modified version 2021) determining the presence of FeLV p27 antigen and FeLV anti-p15E antibodies has become recently commercially available to identify different feline leukaemia virus (FeLV) infection outcomes. This study aimed to assess this PoC test's performance concerning FeLV p27 antigen and FeLV anti-p15E antibody detection. Sensitivity, specificity, positive and negative predictive values (PPV, NPV) were assessed after ten minutes (recommended) and 20 min (prolonged) incubation times. The test results were evaluated as either positive or negative. Serum samples from 934 cats were included, originating from Italy (n = 269), Portugal (n = 240), Germany (n = 318), and France (n = 107). FeLV p27 antigen and anti-p15E antibodies were measured by reference standard ELISAs and compared to the PoC test results. The PoC test was easy to perform and the results easy to interpret. Sensitivity and specificity for FeLV p27 antigen were 82.8% (PPV: 57.8%) and 96.0% (NPV: 98.8%) after both, ten and 20 minues of incubation time. Sensitivity and specificity for anti-p15E antibodies were 31.4% (PPV: 71.6%) and 96.9% (NPV: 85.1%) after ten minutes incubation time; sensitivity was improved by a prolonged incubation time (20 min) to 40.0% (PPV: 76.3%), while specificity remained the same (96.9%, NPV: 86.7%). Despite the improved sensitivity using the prolonged incubation time, lower than ideal sensitivities for both p27 antigen and especially anti-p15E antibodies were found, indicating that the PoC test in its current version needs further improvement prior to application in the field.


Assuntos
Anticorpos Antivirais , Antígenos Virais , Vírus da Leucemia Felina , Testes Imediatos , Antígeno Nuclear de Célula em Proliferação , Animais , Gatos , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Doenças do Gato/diagnóstico , Doenças do Gato/imunologia , Doenças do Gato/virologia , Ensaio de Imunoadsorção Enzimática/métodos , Vírus da Leucemia Felina/imunologia , Leucemia Felina/diagnóstico , Leucemia Felina/imunologia , Leucemia Felina/virologia , Sistemas Automatizados de Assistência Junto ao Leito , Proteínas Oncogênicas de Retroviridae/química , Proteínas Oncogênicas de Retroviridae/imunologia , Sensibilidade e Especificidade
6.
Asp Mol Med ; 1: 100002, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37519861

RESUMO

Rapid on-site diagnosis of emerging pathogens is key for early identification of infected individuals and for prevention of further spreading in a population. Currently available molecular diagnostic tests are instrument-based whereas rapid antibody and antigen tests are often not sufficiently sensitive for detection in pre-symptomatic subjects. There is a need for rapid point of care molecular screening tests that can be easily adapted to emerging pathogens and are selective, sensitive, reliable in different settings around the world. We have developed a simple, rapid (<30 â€‹min), and inexpensive test for SARS-CoV-2 that is based on combination of isothermal reverse transcription recombinase polymerase amplification (RT-RPA) using modified primers and visual detection with paper-based microfluidics. Our test (CoRapID) is specific for SARS-CoV-2 (alpha to omicron variants) and does not detect other coronaviruses and pathogens by in silico and in vitro analysis. A two-step test protocol was developed with stable lyophilized reagents that reduces handling by using portable and disposable components (droppers, microapplicators/swabs, paper-strips). After optimization of assay components and conditions, we have achieved a limit of detection (LoD) of 1 copy/reaction by adding a blocking primer to the lateral flow assay. Using a set of 138 clinical samples, a sensitivity of 88.1% (P â€‹< â€‹0.05, CI: 78.2-93.8%) and specificity of 93.9% (P â€‹< â€‹0.05, CI: 85.4-97.6%) was determined. The lack of need for instrumentation for our CoRapID makes it an ideal on-site primary screening tool for local hospitals, doctors' offices, senior homes, workplaces, and in remote settings around the world that often do not have access to clinical laboratories.

7.
Acta Trop ; 226: 106251, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34808116

RESUMO

Strongyloides stercoralis is a parasite that causes strongyloidiasis worldwide. It may lead to a life-long infection in immunocompetent people and hyperinfection in immunosuppressed patients. A point-of-care (POC) rapid test is helpful for patient diagnosis in resource-limited settings and as a detection tool in elimination/control programs. Previously, we reported a rapid IgG4 dipstick test (Ss Rapid®) for Strongyloides suitable for a laboratory setting. A POC cassette format of the test, which is field-applicable, has since been developed. Here, we report on a laboratory-based evaluation of the Ss Rapid® cas sette test on 285 sera. We assessed the diagnostic sensitivity of the Ss Rapid® cas sette with 32 sera, comprising samples from larval and/or DNA positive individuals from three countries. Additionally, we also tested samples from 33 seropositive endemic areas residents. We evaluated the diagnostic specificity of the test using 220 samples, comprising sera from other infections (n = 101), allergy cases with high IgE antibodies (n = 4), and blood donors (n = 115). The test showed high diagnostic sensitivity (97%, 31/32), and all sera of the seropositive endemic residents were reactive. It also showed high diagnostic specificity (94.5%, 208/220), and all false-positive samples tested negative after sera adsorption using recombinant NIE-coated microsphere beads. Additionally, we showed that the test worked with spiked whole blood samples. The study results showed that the SsRapid® cas sette test merits further laboratory and field evaluations.


Assuntos
Strongyloides stercoralis , Estrongiloidíase , Animais , Anticorpos Anti-Helmínticos , Ensaio de Imunoadsorção Enzimática , Humanos , Sistemas Automatizados de Assistência Junto ao Leito , Sensibilidade e Especificidade , Estrongiloidíase/diagnóstico
8.
Microbiol Spectr ; 10(5): e0019022, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36036635

RESUMO

This study evaluated the BD Veritor system for rapid detection of SARS-CoV-2, an immunochromatographic point-of-care test, by comparing it with a standard reverse transcription-PCR (RT-PCR) methodology using samples from symptomatic patients. Samples from 146 symptomatic and 2 asymptomatic patients between the 1st and the 40th day of infection were evaluated. The nasopharyngeal and/or oropharyngeal swabs were inserted in a tube containing 0.9% saline solution and stored at refrigerator temperature until the moment of use. The samples were first tested with the Xpert Xpress SARS-CoV-2 (GeneXpert) kit (RT-PCR method), and the cycle thresholds (CTs) for the E and N2 genes encoding the SARS-CoV-2 envelope and nucleoprotein, respectively, were established. Subsequently, the same samples were tested using the Veritor rapid test. We analyzed the CTs of the N2 gene, which is detected in both methodologies, and observed sensitivities of 100%, 98.8%, 89.6%, and 82.7% for the CTs of <25, <27, and <30 and all the CTs, respectively. The greatest sensitivity was observed when we performed the test on patients within 5 days of symptom onset. The BD Veritor system's workflow is simple and fast, taking approximately 16 min from sample preparation to obtaining the test result. In addition to its satisfactory sensitivity, with results that correlate with those of the RT-PCR, the BD Veritor analyzer instrument reduces the subjectivity of unaided visual readings and consequent potential variation in result interpretation. Therefore, our results showed that the BD Veritor diagnostic test can provide a rapid and accurate diagnosis for SARS-CoV-2. IMPORTANCE This study provides important and useful information, especially for diagnostic laboratories, since the results show that the BD Veritor system can provide a fast and safe point-of-care antigen diagnostic test for rapid detection of COVID-19 that has high sensitivity, reproducibility, and accuracy.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Transcrição Reversa , Reprodutibilidade dos Testes , Solução Salina , Sensibilidade e Especificidade , Reação em Cadeia da Polimerase , Nucleoproteínas/genética
9.
Clin Chim Acta ; 521: 45-58, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34153274

RESUMO

Sepsis, which includes infection followed by inflammation, is one of the leading causes of death among neonates worldwide. The major attribute of this disease process is dysregulated host response to infection leading to organ dysfunction and potentially death. A comprehensive understanding of the host response as well as the pathogen itself are important factors contributing to outcome. Early diagnosis is paramount, as it leads to accurate assessment and improved clinical management. Accordingly, a number of diagnostic platforms have been introduced to assess the presence of blood stream pathogens in septic neonates. Unfortunately, current point-of-care (POC) methods rely on a single parameter/biomarker and thus lack a comprehensive evaluation. The emerging field of biosensing has, however, resulted in the development of a wide range of analytical devices that may be useful at POC. This review discusses currently available methods to screen the inflammatory process in neonatal sepsis. We describe POC sensor-based methods for single platform multi-analyte detection and highlight the latest advances in this evolving technology. Finally, we critically evaluate the applicability of these POC devices clinically for early diagnosis of sepsis in neonates.


Assuntos
Sepse Neonatal , Sepse , Biomarcadores , Diagnóstico Precoce , Humanos , Recém-Nascido , Sepse Neonatal/diagnóstico , Sistemas Automatizados de Assistência Junto ao Leito , Sepse/diagnóstico
10.
Clin Microbiol Infect ; 27(2): 182-191, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32120036

RESUMO

BACKGROUND: Rapid diagnostic tests (RDTs) for infectious diseases, with a turnaround time of less than 2 hours, are promising tools that could improve patient care, antimicrobial stewardship and infection prevention in the emergency department (ED) setting. Numerous RDTs have been developed, although not necessarily for the ED environment. Their successful implementation in the ED relies on their performance and impact on patient management. OBJECTIVES: The aim of this narrative review was to provide an overview of currently available RDTs for infectious diseases in the ED. SOURCES: PubMed was searched through August 2019 for available studies on RDTs for infectious diseases. Inclusion criteria included: commercial tests approved by the US Food and Drug Administration (FDA) or Conformité Européenne (CE) in vitro diagnostic devices with data on clinical samples, ability to run on fully automated systems and result delivery within 2 hours. CONTENT: A nonexhaustive list of representative commercially available FDA- or CE-approved assays was categorized by clinical syndrome: pharyngitis and upper respiratory tract infection, lower respiratory tract infection, gastrointestinal infection, meningitis and encephalitis, fever in returning travellers and sexually transmitted infection, including HIV. The performance of tests was described on the basis of clinical validation studies. Further, their impact on clinical outcomes and anti-infective use was discussed with a focus on ED-based studies. IMPLICATIONS: Clinicians should be familiar with the distinctive features of each RDT and individual performance characteristics for each target. Their integration into ED work flow should be preplanned considering local constraints of given settings. Additional clinical studies are needed to further evaluate their clinical effectiveness and cost-effectiveness.


Assuntos
Doenças Transmissíveis/diagnóstico , Testes Diagnósticos de Rotina/instrumentação , Testes Diagnósticos de Rotina/métodos , Automação Laboratorial , Doenças Transmissíveis/tratamento farmacológico , Doenças Transmissíveis/etiologia , Aprovação de Teste para Diagnóstico , Serviço Hospitalar de Emergência , Europa (Continente) , Humanos , Kit de Reagentes para Diagnóstico , Estados Unidos , United States Food and Drug Administration
11.
Viruses ; 13(6)2021 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-34072890

RESUMO

The potential of rapid point-of-care (POC) tests has been subject of doubt due to an eventual risk of production errors. The aim was therefore to evaluate the two separate production lots of a commercial POC lateral flow test, intended for the detection of IgM and IgG against the SARS-CoV-2 spike protein (S1). Control samples consisted of serum from individuals with confirmed SARS-CoV-2 infection and pre-COVID-19 negative sera gathered from a biobank. The presence of anti-S1 IgM/IgG in the sera was verified by an in-house Luminex-based serological assay (COVID-19 SIA). One hundred samples were verified as positive for anti-S1 IgG and 74 for anti-S1 IgM. Two hundred samples were verified as negative for anti-S1 IgM/IgG. For the two lots of the POC-test, the sensitivities were 93.2% and 87.8% for IgM and 93.0% and 100% for IgG. The specificities were 100% for IgM and 99.5% for IgG. The positive predictive value was 100% for IgM and 98.9% and 99.0% for IgG. The negative predictive value was 97.6% and 95.7% for IgM, and 96.6% and 100% for IgG. The evaluated POC-test is suitable to assess anti-SARS-CoV-2 S1 IgM and IgG, as a measure of previous virus exposure on an individual level. The external validation of separate lots of rapid POC-tests is encouraged to ensure high sensitivity before market introduction.


Assuntos
Anticorpos Antivirais/sangue , Teste Sorológico para COVID-19/métodos , COVID-19/diagnóstico , Testes Imediatos , Glicoproteína da Espícula de Coronavírus/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Sensibilidade e Especificidade
12.
Diagnostics (Basel) ; 11(7)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206654

RESUMO

Field-applicable, high-quality, and low-cost diagnostic tools are urgently needed for Taenia solium. The aim of this paper is to describe the design, challenges, and rationale for the design of a diagnostic accuracy study in low-resource community settings in Zambia. The trial was designed as a prospective study with a two-stage design to evaluate a new point-of-care test (TS POC) for the detection of taeniosis and (neuro)cysticercosis. Participants within randomly selected households were tested with the TS POC test (index test). Participants who tested TS POC positive for taeniosis and/or cysticercosis and a subset of the negatives were requested to give blood and stool samples for reference testing, and to undergo clinical examination and a cerebral CT scan. The difficulties of conducting a clinical trial in settings with limited research and neuroimaging infrastructure as well as peculiarities specifically related to the disease (low prevalence of taeniosis and the lack of a gold standard) were taken into consideration for the design of this study. The two-stage design increased the efficiency of the study by reducing the number of samples, clinical examinations, and CT scans. Simplified flows and sampling processes were preferred over complex follow-up and randomization systems, aiming to reduce bias and increase the generalizability of the study.

13.
J Virol Methods ; 293: 114166, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33872651

RESUMO

INTRODUCTION: As the second wave of COVID-19 pandemic is in progress the development of fast and cost-effective approaches for diagnosis is essential. The aim of the present study was to develop and evaluate the performance characteristics of a new Bioelectric Recognition Assay (BERA) regarding Sars-CoV-2 detection in clinical samples and its potential to be used as a point of care test. MATERIALS AND METHODS: All tests were performed using a custom portable hardware device developed by EMBIO DIAGNOSTICS (EMBIO DIAGNOSTICS Ltd, Cyprus). 110 positive and 136 negative samples tested by RT-PCR were used in order to define the lower limit of detection (L.O.D.) of the system, as well as the sensitivity and the specificity of the method. RESULTS: The system was able to detect a viral concentration of 4 genome copies/µL. The method displayed total sensitivity of 92.7 % (95 %CI: 86.2-96.8) and 97.8 % specificity (95 %CI: 93.7-99.5). When samples were grouped according to the recorded Ct values the BERA biosensor displayed 100.00 % sensitivity (95 %CI: 84.6-100.0) for Ct values <20-30. For the aforementioned Ct values the Positive Predictive Value (PPV) of the method was estimated at 31.4 % for COVID-19 prevalence of 1% and at 70.5 % for 5% prevalence. At the same time the Negative Predictive Value (NPV) of the BERA biosensor was at 100.0 % for both prevalence rates. CONCLUSIONS: EMBIO DIAGNOSTICS BERA for the detection of SARS-CoV-2 infection has the potential to allow rapid and cost-effective detection and subsequent isolation of confirmed cases, and therefore reduce household and community transmissions.


Assuntos
Técnicas Biossensoriais/métodos , COVID-19/diagnóstico , Testes Imediatos , SARS-CoV-2/isolamento & purificação , Animais , Chlorocebus aethiops , Humanos , Limite de Detecção , Sensibilidade e Especificidade , Células Vero
14.
Talanta ; 233: 122538, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215041

RESUMO

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common enzymopathy in humans. More than 400 million people worldwide are affected by this genetic condition. Testing for G6PD deficiency before drug administration is essential for patient safety. Rapidly ascertaining the G6PD status of a person is desirable for proper treatment. The device described in this study, the G6PD diaxBOX, was developed to quantify G6PD deficiency using paper-based analytical devices (PADs) and a colorimetric assay. The G6PD diaxBOX is a straightforward, affordable, portable, and instrument-free analytical system. The major components of the G6PD diaxBox are a banknote-checking UV fluorescent lamp and camera that are easy to access and analysis software. When NADPH is generated, it absorbs at UV 340 nm and emits colored light that is detected with the camera. The determined Pearson's coefficient shows that the color intensity measured from the G6PD diaxBOX correlated with G6PD activity level. Also, a Bland-Altman analysis indicated that more than 95% of the measurement error was in the upper and lower boundaries (±2 SD) and the error from the severe and moderate deficiency group was less than ± 1 SD. Therefore, the error from G6PD diaxBOX was within the limit boundary and the overall accuracy was more than 80%. The G6PD diaxBOX facilitates the effective and efficient quantification of G6PD deficiency and as such represents a clinically well-suited, rapid point-of-care test.


Assuntos
Deficiência de Glucosefosfato Desidrogenase , Glucosefosfato Desidrogenase , Colorimetria , Humanos , Testes Imediatos , Software
15.
Viruses ; 13(1)2020 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-33374843

RESUMO

Measuring antibodies to evaluate dogs' immunity against canine parvovirus (CPV) is useful to avoid unnecessary re-vaccinations. The study aimed to evaluate the quality and practicability of four point-of-care (POC) tests for detection of anti-CPV antibodies. The sera of 198 client-owned and 43 specific pathogen-free (SPF) dogs were included; virus neutralization was the reference method. Specificity, sensitivity, positive and negative predictive value (PPV and NPV), and overall accuracy (OA) were calculated. Specificity was considered to be the most important indicator for POC test performance. Differences between specificity and sensitivity of POC tests in the sera of all dogs were determined by McNemar, agreement by Cohen's kappa. Prevalence of anti-CPV antibodies in all dogs was 80% (192/241); in the subgroup of client-owned dogs, it was 97% (192/198); and in the subgroup of SPF dogs, it was 0% (0/43). FASTest® and CanTiCheck® were easiest to perform. Specificity was highest in the CanTiCheck® (overall dogs, 98%; client-owned dogs, 83%; SPF dogs, 100%) and the TiterCHEK® (overall dogs, 96%; client-owned dogs, 67%; SPF dogs, 100%); no significant differences in specificity were observed between the ImmunoComb®, the TiterCHEK®, and the CanTiCheck®. Sensitivity was highest in the FASTest® (overall dogs, 95%; client-owned dogs, 95%) and the CanTiCheck® (overall dogs, 80%; client-owned dogs, 80%); sensitivity of the FASTest® was significantly higher compared to the one of the other three tests (McNemars p-value in each comparison: <0.001). CanTiCheck® would be the POC test of choice when considering specificity and practicability. However, differences in the number of false positive results between CanTiCheck®, TiterCHEK®, and ImmunoComb® were minimal.


Assuntos
Anticorpos Antivirais/imunologia , Doenças do Cão/diagnóstico , Doenças do Cão/imunologia , Infecções por Parvoviridae/veterinária , Parvovirus Canino/imunologia , Testes Imediatos , Kit de Reagentes para Diagnóstico , Animais , Anticorpos Antivirais/sangue , Vírus da Cinomose Canina/imunologia , Doenças do Cão/epidemiologia , Cães , Kit de Reagentes para Diagnóstico/normas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estudos Soroepidemiológicos , Testes Sorológicos/métodos , Testes Sorológicos/normas
16.
Sens Int ; 1: 100015, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-34766037

RESUMO

Point-of-care (POC) diagnostic device is an instrument that is used to acquire particular clinical information of patients in clinical as well as resource-limited settings. The conventional clinical diagnostic procedure requires high-end and costly instruments, an expert technician for operation and result interpretation, longer time, etc. that ultimately makes it exhausting and expensive. Although there are a lot of improvements in the medical facilities in the Indian healthcare system, the use of POC diagnostic devices is still in its nascent phase. This review illustrates the status of POC diagnostic devices currently used in clinical setups along with constraints in their use. The devices and technologies that are in the research and development phase across the country that has tremendous potential to elevate the clinical diagnostics scenario along with the diagnosis of ongoing COVID-19 pandemic are emphasized. The implications of using POC diagnostic devices and the future objectives for technological advancements that may eventually uplift the status of healthcare and related sectors in India are also discussed here.

17.
Ann Glob Health ; 83(2): 394-404, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28619417

RESUMO

BACKGROUND: Prevention and control of chronic diseases is a high priority for many low- and middle-income countries. This study evaluated the feasibility and acceptability of training pharmacy workers to provide point-of-care testing for 3 chronic diseases-hypertension, diabetes, and anemia-to improve disease detection and awareness through private pharmacies. METHODS: We developed a multiphase training curriculum for pharmacists and pharmacy technicians to build capacity for identification of risk factors, patient education, point-of-care testing, and referral for abnormal results. We conducted a pre-post evaluation with participants and evaluated results using Student t test for proportions. We conducted point-of-care testing with pharmacy clients and evaluated acceptability by patient characteristics (age, gender, and type of patient) using multiple logistic regression. RESULTS: In total, 72 pharmacy workers (66%) completed the full training curriculum. Pretest scores indicated that pharmacists had more knowledge and skills in chronic disease risk factors, patient education, and testing than pharmacy technicians. All participants improved their knowledge and skills after the training, and post-test scores indicated that pharmacy technicians achieved the same level of competency as pharmacists (P < .01). Additionally, 698 clients received at least 1 test during the study; 53% completed the acceptability survey. Nearly 100% thought the pharmacy could provide faster results, faster and better attention, and better access to basic screening for hypertension, diabetes, and anemia than a traditional health center. Fast service was very important: 41% ranked faster results and 30% ranked faster attention as the most important factor for receiving diagnostic testing in the pharmacy. DISCUSSION: We found that it is both feasible for pharmacies and acceptable to clients to train pharmacy workers to provide point-of-care testing for anemia, diabetes, and hypertension. This innovative approach holds potential to increase early detection of risk factors and bolster disease prevention and management efforts in Peru and other low- and middle-income settings.


Assuntos
Anemia/diagnóstico , Diabetes Mellitus/diagnóstico , Hipertensão/diagnóstico , Aceitação pelo Paciente de Cuidados de Saúde , Assistência Farmacêutica/organização & administração , Testes Imediatos , Humanos , Educação de Pacientes como Assunto , Peru
18.
J Matern Fetal Neonatal Med ; 29(15): 2414-22, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26643648

RESUMO

OBJECTIVE: Mid-trimester amniocentesis continues to be used for the prenatal diagnosis of chromosomal anomalies and other genetic disorders. Analysis of amniotic fluid obtained at the time of mid-trimester genetic amniocentesis identifies those patients who are at risk for early spontaneous preterm delivery. This is based on a solid body of evidence that found subclinical intra-amniotic inflammation/infection to be causally linked to early spontaneous preterm birth. Although several biomarkers have been proposed to identify intra-amniotic inflammation, the accumulated data suggest that the determination of amniotic fluid matrix metalloproteinase-8 (MMP-8), or neutrophil collagenase, is a powerful predictor of spontaneous preterm delivery. MMP-8 is released by inflammatory cells in response to microbial products or "danger signals". A rapid point-of-care test has been developed to determine MMP-8 at the bedside within 20 min, and without the requirement of laboratory equipment. The objective of this study was to determine whether an elevation of MMP-8 in the amniotic fluid, measured by a rapid point-of-care test, can identify those patients at risk for spontaneous preterm delivery after a mid-trimester genetic amniocentesis. STUDY DESIGN: A case-control study was designed to obtain amniotic fluid from asymptomatic singleton pregnant women who underwent mid-trimester genetic amniocentesis. An MMP-8 bedside test was performed to analyze the amniotic fluid of 64 patients with early spontaneous preterm delivery (<30 weeks) and 128 matched controls with normal pregnancy outcomes. RESULTS: (1) The MMP-8 bedside test (Yoon's MMP-8 Check™) was positive in 42.2% (27/64) of patients with spontaneous preterm delivery but in none (0/128) of the control cases (p < 0.001); (2) the MMP-8 bedside test had a sensitivity of 42.2%, and a specificity of 100% in the prediction of spontaneous preterm delivery (<30 weeks) following a mid-trimester genetic amniocentesis; and (3) among the patients with spontaneous preterm delivery, those with a positive MMP-8 bedside test had a significantly higher rate of spontaneous delivery within 2 weeks and 4 weeks of an amniocentesis [40.7% (11/27) versus 5.4% (2/37); 63.0% (17/27) versus 24.3% (9/37)] and a shorter interval-to-delivery period than those with a negative test [interval-to-delivery: median (range), 16 d (0-95 d) versus 42 d (2-91 d); p < 0.05 for each]. CONCLUSION: We conclude that 42% of patients with an early spontaneous preterm delivery (< 30 weeks) could be identified by a rapid MMP-8 bedside test at the time of their mid-trimester genetic amniocentesis. The MMP-8 bedside test is a powerful predictor of early spontaneous preterm birth in asymptomatic pregnant women.


Assuntos
Amniocentese/métodos , Líquido Amniótico/metabolismo , Metaloproteinase 8 da Matriz/análise , Sistemas Automatizados de Assistência Junto ao Leito , Nascimento Prematuro/metabolismo , Adulto , Biomarcadores/análise , Estudos de Casos e Controles , Feminino , Humanos , Recém-Nascido , Gravidez , Resultado da Gravidez , Trimestres da Gravidez , Nascimento Prematuro/diagnóstico , Medição de Risco , Sensibilidade e Especificidade
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