scholarly journals Anemia Diagnosis on a Simple Paper-based Assay

2018 ◽  
Author(s):  
Sujay K Biswas ◽  
Soumya Bandyopadhyay ◽  
Shantimoy Kar ◽  
Nirmal K Som ◽  
Suman Chakraborty
Keyword(s):  
Gold Standard ◽  
Diagnostic Tests ◽  
State Of The Art ◽  
Wide Spectrum ◽  
Point Of Care ◽  
Test Method ◽  
High Fidelity ◽  
Neonatal Mortality Rate ◽  
Blood Samples ◽  
Mild Anemia

AbstractIn developing countries, the maternal and neonatal mortality rate is often affected by prenatal period anemia, a preventable and ubiquitous impairment attributed due to low hemoglobin (Hgb) concentration. We report the development of a simple, frugal (~ 0.02 $ per test), rapid and high fidelity paper-based colorimetric microfluidic device for point-of-care (POC) detection of anemia. We validate our findings with 32 blood samples collected from different patients covering a wide spectrum of anemia and subsequently, compare with standard pathological results measured using a hematology analyzer. POC based Hgb estimates are correlated with the pathological gold standard estimates of Hgb levels (r = 0.909), and the POC test method yielded similar sensitivity and specificity for detecting mild anemia (n = 8) (<11 g/dl) (sensitivity: 87.5%, specificity: 100 %) and for severe anemia (n = 3) (<7 g/dl) (sensitivity: 100 %, specificity: 100 %). The estimated Hgb levels are, within 1.5 g/dl from the pathological estimate, for 91 % of the blood samples. Results demonstrate the elevated efficacy and viability of this POC colorimetric diagnostic test, in comparison to the state-of-the-art complex and expensive diagnostic tests for anemia detection.

scholarly journals Clinical Evaluation of QuickNaviTM-Ebola in the 2018 Outbreak of Ebola Virus Disease in the Democratic Republic of the Congo

Viruses ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 589 ◽  
Author(s):  
Sheila Makiala ◽  
Daniel Mukadi ◽  
Anja De Weggheleire ◽  
Shino Muramatsu ◽  
Daisuke Kato ◽  
...  
Keyword(s):  
West Africa ◽  
Diagnostic Tests ◽  
Ebola Virus ◽  
Democratic Republic ◽  
Virus Disease ◽  
Point Of Care ◽  
Rapid Diagnostic Tests ◽  
Ebola Virus Disease ◽  
Blood Samples ◽  
Republic Of The Congo

The recent large outbreaks of Ebola virus disease (EVD) in West Africa and the Democratic Republic of the Congo (DRC) have highlighted the need for rapid diagnostic tests to control this disease. In this study, we clinically evaluated a previously developed immunochromatography-based kit, QuickNaviTM-Ebola. During the 2018 outbreaks in DRC, 928 blood samples from EVD-suspected cases were tested with QuickNaviTM-Ebola and the WHO-approved GeneXpert. The sensitivity and specificity of QuickNaviTM-Ebola, estimated by comparing it to GeneXpert-confirmed cases, were 85% (68/80) and 99.8% (846/848), respectively. These results indicate the practical reliability of QuickNaviTM-Ebola for point-of-care diagnosis of EVD.

scholarly journals Comparative study of direct and indirect immunofluorescence for diagnosis of canine pemphigus foliaceus

2018 ◽  
Vol 70 (3) ◽  
pp. 649-655
Author(s):  
J.S. Severo ◽  
V. Aoki ◽  
A.E. Santana ◽  
M.M. Mantovani ◽  
N.S. Michalany ◽  
...  
Keyword(s):  
Indirect Immunofluorescence ◽  
Gold Standard ◽  
Diagnostic Tests ◽  
Histopathological Examination ◽  
Pemphigus Foliaceus ◽  
Kappa Index ◽  
Standard Pattern ◽  
Blood Samples ◽  
Group I ◽  
Complementary Examination

ABSTRACT Pemphigus foliaceus (PF) is the most common autoimmune skin disease in dogs. It is characterized by pustules, erosions, and crusts which occur due to the presence of autoantibodies that target intercellular adhesion. Histopathological examination is considered the gold standard pattern in the diagnosis, but may sometimes be inconclusive, especially when the characteristic findings are not identified. New diagnostic tests are continuously being developed and immunofluorescence assays, could be a valuable alternative diagnostic tool. This study aimed to evaluate the applicability of direct and indirect immunofluorescence (DIF and IIF) tests for the diagnosis of canine PF. Twenty eight dogs were divided into two groups: Group I with 14 dogs with PF and Group II (control) with 14 dogs with Superficial pyoderma (differential diagnoses of PF). All animals were submitted to skin biopsy to histopathological and DIF. Blood samples were collected to assess IIF. Comparing the DIF results against the histopathology test, there was an agreement of 75% (9/12) with a Kappa index of 0.77 (P<0.001). Considering IIF, the agreement was 100% (14/14), with a Kappa index of 1.0 (P<0.001). We conclude that DIF and IIF are highly effective and were useful and effective complementary examination tests for an improvement in the diagnosis of canine PF.

scholarly journals Paper-Based Point-of-Care Testing of SARS-CoV-2

2021 ◽  
Vol 9 ◽  
Author(s):  
Yuan Jia ◽  
Hao Sun ◽  
Jinpeng Tian ◽  
Qiuming Song ◽  
Wenwei Zhang
Keyword(s):  
Diagnostic Tests ◽  
State Of The Art ◽  
Point Of Care ◽  
Low Cost ◽  
The State ◽  
Detection Methods ◽  
Point Of Care Testing ◽  
Research Opportunities ◽  
Acute Infections ◽  
Reliable Detection

The COVID-19 pandemic has resulted in significant global social and economic disruption. The highly transmissive nature of the disease makes rapid and reliable detection critically important. Point-of-care (POC) tests involve performing diagnostic tests outside of a laboratory that produce a rapid and reliable result. It therefore allows the diagnostics of diseases at or near the patient site. Paper-based POC tests have been gaining interest in recent years as they allow rapid, low-cost detection without the need for external instruments. In this review, we focus on the development of paper-based POC devices for the detection of SARS-CoV-2. The review first introduces the principles of detection methods that are available to paper-based devices. It then summarizes the state-of-the-art paper devices and their analytical performances. The advantages and drawbacks among methods are also discussed. Finally, limitations of the existing devices are discussed, and prospects are given with the hope to identify research opportunities and directions in the field. We hope this review will be helpful for researchers to develop a clinically useful and economically efficient paper-based platform that can be used for rapid, accurate on-site diagnosis to aid in identifying acute infections and eventually contain the COVID-19 pandemic.

scholarly journals CRISPR-Based Assays for Rapid Detection of SARS-CoV-2

2020 ◽  
Author(s):  
Vivek S. Javalkote ◽  
Nagesh Kancharla ◽  
Bhaskar Bhadra ◽  
Manish Shukla ◽  
Badrish Soni ◽  
...  
Keyword(s):  
Gold Standard ◽  
Diagnostic Tests ◽  
Rapid Detection ◽  
State Of The Art ◽  
Global Public Health ◽  
Rt Pcr ◽  
Serological Tests ◽  
Detection Techniques ◽  
Sample Throughput ◽  
Detection And Diagnosis

COVID-19 represents an unprecedented threat to global public health and economies. Assays are urgently needed for rapid detection and diagnosis of SARS-CoV-2-infected patients in order to inform treatment and quarantine strategies. Establishing globally accepted easy-to-access diagnostic tests is extremely important to understanding the epidemiology of the present pandemic. While nucleic acid-based tests are considered to be more sensitive with respect to serological tests, but the present gold standard RT-PCR-based assays possess limitations such as low sample throughput, requirement for sophisticated reagents and instrumentation. To overcome these shortcomings, recent efforts of incorporating LAMP-based isothermal detection, and minimizing the number of reagents required are on rise. Novel CRISPR- and other nuclease-based techniques, when merge with isothermal and allied technologies, promises to provide sensitive and rapid detection of SARS-CoV-2 nucleic acids. Here we discuss and present compilation of state-of-the-art CRISPR based detection techniques for use in COVID diagnosis and epidemiology.

scholarly journals Point-of-Care Strategies Applied to Malaria Diagnosis

2021 ◽  
Author(s):  
Alexandre Dias Tavares Costa ◽  
Anna Caroline Campos Aguiar ◽  
Angelina Moraes Silva ◽  
Dhelio Batista Pereira
Keyword(s):  
Gold Standard ◽  
Diagnostic Tests ◽  
Point Of Care ◽  
Low Cost ◽  
Malaria Diagnosis ◽  
Standard Test ◽  
Mixed Infections ◽  
Specific Diagnosis ◽  
Disease Diagnostics ◽  
Drop Technique

Rapid and specific diagnosis of malaria remains one of the main strategies to fight the disease. The diagnosis is made primarily by the simple and low-cost thick drop technique, considered the gold standard test. However, the requirement for good quality microscopes and well-trained personnel often lead to inaccurate diagnosis, especially in cases of mixed infections or low parasitemia. Although PCR-based tests can help in these situations, this technique requires large and sensitive equipments, being unsuitable for point of care (POC) settings. A myriad of POC diagnostic tests have being developed in the last years, relying on molecular methods but also on novel strategies. New platforms, miniaturization techniques, and multiplexing possibilities promise great potential to improve disease diagnostics through fast and accurate detection of cases, even at remote places. Here, we will address the main POC strategies developed for the diagnosis of malaria, highlighting their strengths and weakness as POC applications.

Magnetic Digital Microfluidics for Point-of-Care Testing: Where Are We Now?

2020 ◽  
Vol 27 ◽  
Author(s):  
Yi Zhang
Keyword(s):  
System Integration ◽  
Diagnostic Tests ◽  
Point Of Care ◽  
Digital Microfluidics ◽  
Controlled Environment ◽  
Point Of Care Testing ◽  
Microfluidic Platforms ◽  
Interface System ◽  
Technical Issues ◽  
Sample System

: Point-of-care (POC) testing decentralizes the diagnostic tests to the sites near the patient. Many POC tests rely microfluidic platforms for sample-to-answer analysis. Compared to other microfluidic systems, magnetic digital microfluidics demonstrate compelling advantages for POC diagnostics. In this review, we have examined the capability of magnetic digital microfluidics-based POC diagnostic platforms. More importantly, we have categorized POC settings into three classes based on “where is the point”, “who to care” and “how to test”, and evaluated the suitability of magnetic digital microfluidics in various POC settings. Furthermore, we have addressed other technical issues associated with POC testing such as controlled environment, sample-system interface, system integration and information connectivity. We hope this review would provide a guideline for the future development of magnetic digital microfluidics-based platforms for POC testing.

scholarly journals Evaluation of four different HPLC devices for hemoglobinopathy screening

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Müjgan Ercan Karadağ ◽  
Emiş Deniz Akbulut ◽  
Esin Avcı ◽  
Esra Fırat Oğuz ◽  
Saadet Kader ◽  
...  
Keyword(s):  
Gold Standard ◽  
High Performance ◽  
Public Health Problem ◽  
Reference Value ◽  
Comparison Study ◽  
Gold Standard Method ◽  
Blood Samples ◽  
Systematic Biases ◽  
Hemoglobin Variants ◽  
Thalassemia Screening

AbstractObjectiveHemoglobinopathies are a common public health problem in Turkey. In the screening of these disorders in population, cation-exchange high performance liquid chromatography (HPLC) is accepted as the gold standard method. In this study, the aim was to assess four different HPLC devices used in hemoglobinopathy screening.Materials and methodsA total of 58 blood samples were analyzed with four different HPLC methods (Bio-Rad variant II, Agilent 1100, Tosoh G8 and Trinity Ultra2 trademarks).ResultsThe comparison study demonstrated a good correlation between the results of each HPLC analyzer and the reference value obtained by averaging all the HbA2 results belonging to the methods tested in the study [ (Tosoh G8 (r=0.988), Bio-Rad variant II (r=0.993), Agilent 1100 (r=0.98) and Trinity Ultra2 (r=0.992) ]. HbA2 determination in the presence of HbE was interfered in both Bio-Rad variant II and Tosoh G8.ConclusionThe analyzers were found to have compatible HbA2 results but with accompanying different degrees of proportional and systematic biases. HPLC analyzers may be affected by different hemoglobin variants at different HbA2 concentrations, which is an important point to take into consideration during the evaluation of HbA2 results in thalassemia screening.

scholarly journals Design and experimental investigation of a novel spiral microfluidic chip to separate wide size range of micro-particles aimed at cell separation

2021 ◽  
pp. 095441192110297
Author(s):  
Seyed Ali Tabatabaei ◽  
Mohammad Zabetian Targhi
Keyword(s):  
Point Of Care ◽  
Diagnostic System ◽  
Average Diameter ◽  
Microfluidic System ◽  
Microfluidic Chips ◽  
Medical Sciences ◽  
Blood Samples ◽  
Micro Particles ◽  
Monodisperse Polystyrene ◽  
Device Size

Isolation of microparticles and biological cells on microfluidic chips has received considerable attention due to their applications in numerous areas such as medical and engineering fields. Microparticles separation is of great importance in bioassays due to the need for smaller sample and device size and lower manufacturing costs. In this study, we first explain the concepts of separation and microfluidic science along with their applications in the medical sciences, and then, a conceptual design of a novel inertial microfluidic system is proposed and analyzed. The PDMS spiral microfluidic device was fabricated, and its effects on the separation of particles with sizes similar to biological particles were experimentally analyzed. This separation technique can be used to separate cancer cells from the normal ones in the blood samples. These components required for testing were selected, assembled, and finally, a very affordable microfluidic kit was provided. Different experiments were designed, and the results were analyzed using appropriate software and methods. Separator system tests with polydisperse hollow glass particles (diameter 2–20 µm), and monodisperse Polystyrene particles (diameter 5 & 15 µm), and the results exhibit an acceptable chip performance with 86% of efficiency for both monodisperse particles and polydisperse particles. The microchannel collects particles with an average diameter of 15.8, 9.4, and 5.9 μm at the proposed reservoirs. This chip can be integrated into a more extensive point-of-care diagnostic system to test blood samples.

scholarly journals Antibody Responses in Cats Following Primary and Annual Vaccination against Feline Immunodeficiency Virus (FIV) with an Inactivated Whole-Virus Vaccine (Fel-O-Vax® FIV)

Viruses ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 470
Author(s):  
Mark Westman ◽  
Dennis Yang ◽  
Jennifer Green ◽  
Jacqueline Norris ◽  
Richard Malik ◽  
...  
Keyword(s):  
Antibody Response ◽  
Virus Vaccine ◽  
Point Of Care ◽  
Primary Vaccination ◽  
Antibody Responses ◽  
Blood Samples ◽  
Study Results ◽  
Elisa Testing ◽  
Primary Antibody Response ◽  
Residual Blood

Although the antibody response induced by primary vaccination with Fel-O-Vax® FIV (three doses, 2–4 weeks apart) is well described, the antibody response induced by annual vaccination with Fel-O-Vax® FIV (single dose every 12 months after primary vaccination) and how it compares to the primary antibody response has not been studied. Residual blood samples from a primary FIV vaccination study (n = 11), and blood samples from cats given an annual FIV vaccination (n = 10), were utilized. Samples from all 21 cats were tested with a commercially available PCR assay (FIV RealPCRTM), an anti-p24 microsphere immunoassay (MIA), an anti-FIV transmembrane (TM; gp40) peptide ELISA, and a range of commercially available point-of-care (PoC) FIV antibody kits. PCR testing confirmed all 21 cats to be FIV-uninfected for the duration of this study. Results from MIA and ELISA testing showed that both vaccination regimes induced significant antibody responses against p24 and gp40, and both anti-p24 and anti-gp40 antibodies were variably present 12 months after FIV vaccination. The magnitude of the antibody response against both p24 and gp40 was significantly higher in the primary FIV vaccination group than in the annual FIV vaccination group. The differences in prime versus recall post-vaccinal antibody levels correlated with FIV PoC kit performance. Two FIV PoC kits that detect antibodies against gp40, namely Witness® and Anigen Rapid®, showed 100% specificity in cats recently administered an annual FIV vaccination, demonstrating that they can be used to accurately distinguish vaccination and infection in annually vaccinated cats. A third FIV PoC kit, SNAP® Combo, had 0% specificity in annually FIV-vaccinated cats, and should not be used in any cat with a possible history of FIV vaccination. This study outlines the antibody response to inactivated Fel-O-Vax® FIV whole-virus vaccine, and demonstrates how best to diagnose FIV infection in jurisdictions where FIV vaccination is practiced.

scholarly journals Evaluation of a Preclinical Blood Test for Scrapie in Sheep Using Immunocapillary Electrophoresis

2006 ◽  
Vol 89 (3) ◽  
pp. 720-727 ◽  
Author(s):  
Roy Jackman ◽  
David J Everest ◽  
Mary Jo Schmerr ◽  
Mohammed Khawaja ◽  
Pat Keep ◽  
...  
Keyword(s):  
Capillary Electrophoresis ◽  
Prion Protein ◽  
Clinical Signs ◽  
Test System ◽  
Buffy Coat ◽  
Infected Sheep ◽  
Test Method ◽  
Peptide Sequence ◽  
Transmissible Spongiform Encephalopathies ◽  
Blood Samples

Abstract An analytical method is described for detection of endogenous disease-associated prion protein in the buffy coat fraction from the blood of sheep infected with scrapie. The method has been improved and evaluated for its performance in the preclinical diagnosis of ovine transmissible spongiform encephalopathies. The test system uses a protocol for sample preparation that includes extraction and concentration and a test method that uses a liquid-phase competitive immunoassay for prion protein. Antibodies directed to a peptide sequence at the C-terminus of the prion protein (PrP) and a fluorescein-labeled peptide conjugate are used in the assay. Free zone capillary electrophoresis with laser-induced fluorescence for detection is used to separate the antibody-bound fluorescently labeled peptide and free labeled peptide. In this assay, the PrP competes with the fluorescently labeled peptide for limited antibody binding sites, which results in a reduction of the peak representing the immunocomplex of the antibody bound to the fluorescently labeled peptide. When blood samples from scrapie-infected sheep aged 712 months and of the scrapie-susceptible PrP genotypes VRQ/VRQ and VRQ/ARQ were analyzed, the abnormal PrP was found in blood samples. These results correlated with the post-mortem diagnosis of scrapie. The sheep were preclinical and appeared normal at the time of testing but later died with clinical disease approximately 12 months after testing. In older animals, and those with clinical signs, a smaller percentage of animals tested positive. This study has demonstrated that this technology can be used as a sensitive, rapid preclinical test to detect the disease-associated PrP in the blood of scrapie-infected sheep. Improvements in the extraction protocol and capillary electrophoresis conditions will enhance the robustness of this test.

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