scholarly journals A Strategy to Detect Emerging Non-Delta SARS-CoV-2 Variants with a Monoclonal Antibody Specific for the N501 Spike Residue

Diagnostics ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 2092
Author(s):  
Rama Devudu Puligedda ◽  
Fetweh H. Al-Saleem ◽  
Cristoph Wirblich ◽  
Chandana Devi Kattala ◽  
Marko Jović ◽  
...  
Keyword(s):  
Point Of Care ◽  
Sandwich Elisa ◽  
Rapid Diagnostic Tests ◽  
Host Immunity ◽  
Detection Methods ◽  
Diagnostic Categories ◽  
Antibody Therapeutics ◽  
Control And Prevention ◽  
Predominant Variant ◽  
Diagnostic Detection

Efforts to control SARS-CoV-2 have been challenged by the emergence of variant strains that have important implications for clinical and epidemiological decision making. Four variants of concern (VOCs) have been designated by the Centers for Disease Control and Prevention (CDC), namely, B.1.617.2 (delta), B.1.1.7 (alpha), B.1.351 (beta), and P.1 (gamma), although the last three have been downgraded to variants being monitored (VBMs). VOCs and VBMs have shown increased transmissibility and/or disease severity, resistance to convalescent SARS-CoV-2 immunity and antibody therapeutics, and the potential to evade diagnostic detection. Methods are needed for point-of-care (POC) testing to rapidly identify these variants, protect vulnerable populations, and improve surveillance. Antigen-detection rapid diagnostic tests (Ag-RDTs) are ideal for POC use, but Ag-RDTs that recognize specific variants have not yet been implemented. Here, we describe a mAb (2E8) that is specific for the SARS-CoV-2 spike protein N501 residue. The 2E8 mAb can distinguish the delta VOC from variants with the N501Y meta-signature, which is characterized by convergent mutations that contribute to increased virulence and evasion of host immunity. Among the N501Y-containing mutants formerly designated as VOCs (alpha, beta, and gamma), a previously described mAb, CB6, can distinguish beta from alpha and gamma. When used in a sandwich ELISA, these mAbs sort these important SARS-CoV-2 variants into three diagnostic categories, namely, (1) delta, (2) alpha or gamma, and (3) beta. As delta is currently the predominant variant globally, they will be useful for POC testing to identify N501Y meta-signature variants, protect individuals in high-risk settings, and help detect epidemiological shifts among SARS-CoV-2 variants.

Re-challenging antibiotic resistance with Daniel Berman

2020 ◽  
Author(s):  
Daniel Berman
Keyword(s):  
Bacterial Infections ◽  
Point Of Care ◽  
Healthcare Setting ◽  
Rapid Diagnostic Tests ◽  
Resistant Bacteria ◽  
Drug Resistant ◽  
Drug Resistant Bacteria ◽  
Global Threat ◽  
The Right ◽  
Point Of Care Tests

How can we prevent the rise of resistance to antibiotics? In this video, Daniel Berman,  Nesta Challenges, discusses the global threat of AMR and how prizes like the Longitude Prize can foster the development of rapid diagnostic tests for bacterial infections, helping to contribute towards reducing the global threat of drug resistant bacteria. Daniel outlines how accelerating the development of rapid point-of-care tests will ensure that bacterial infections are treated with the most appropriate antibiotic, at the right time and in the right healthcare setting.

scholarly journals Rapid and Sensitive Detection of miRNA Based on AC Electrokinetic Capacitive Sensing for Point-of-Care Applications

Sensors ◽  
2021 ◽  
Vol 21 (12) ◽  
pp. 3985
Author(s):  
Nan Wan ◽  
Yu Jiang ◽  
Jiamei Huang ◽  
Rania Oueslati ◽  
Shigetoshi Eda ◽  
...  
Keyword(s):  
Limit Of Detection ◽  
Point Of Care ◽  
Low Cost ◽  
Clinical Diagnostics ◽  
Detection Methods ◽  
Capacitive Sensing ◽  
Application Potential ◽  
Mirna Detection ◽  
Mirna 25 ◽  
Low Sensitivity

A sensitive and efficient method for microRNAs (miRNAs) detection is strongly desired by clinicians and, in recent years, the search for such a method has drawn much attention. There has been significant interest in using miRNA as biomarkers for multiple diseases and conditions in clinical diagnostics. Presently, most miRNA detection methods suffer from drawbacks, e.g., low sensitivity, long assay time, expensive equipment, trained personnel, or unsuitability for point-of-care. New methodologies are needed to overcome these limitations to allow rapid, sensitive, low-cost, easy-to-use, and portable methods for miRNA detection at the point of care. In this work, to overcome these shortcomings, we integrated capacitive sensing and alternating current electrokinetic effects to detect specific miRNA-16b molecules, as a model, with the limit of detection reaching 1.0 femto molar (fM) levels. The specificity of the sensor was verified by testing miRNA-25, which has the same length as miRNA-16b. The sensor we developed demonstrated significant improvements in sensitivity, response time and cost over other miRNA detection methods, and has application potential at point-of-care.

scholarly journals Optical-Based Biosensors and Their Portable Healthcare Devices for Detecting and Monitoring Biomarkers in Body Fluids

Diagnostics ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1285
Author(s):  
Anh Tran Tam Pham ◽  
Angus Wallace ◽  
Xinyi Zhang ◽  
Damian Tohl ◽  
Hao Fu ◽  
...  
Keyword(s):  
Medical Devices ◽  
Point Of Care ◽  
Body Fluids ◽  
Optical Measurements ◽  
Mobile Technologies ◽  
Detection Methods ◽  
Portable Devices ◽  
Bodily Fluids ◽  
Clinical Measurements ◽  
Distinct Features

The detection and monitoring of biomarkers in body fluids has been used to improve human healthcare activities for decades. In recent years, researchers have focused their attention on applying the point-of-care (POC) strategies into biomarker detection. The evolution of mobile technologies has allowed researchers to develop numerous portable medical devices that aim to deliver comparable results to clinical measurements. Among these, optical-based detection methods have been considered as one of the common and efficient ways to detect and monitor the presence of biomarkers in bodily fluids, and emerging aggregation-induced emission luminogens (AIEgens) with their distinct features are merging with portable medical devices. In this review, the detection methodologies that use optical measurements in the POC systems for the detection and monitoring of biomarkers in bodily fluids are compared, including colorimetry, fluorescence and chemiluminescence measurements. The current portable technologies, with or without the use of smartphones in device development, that are combined with optical biosensors for the detection and monitoring of biomarkers in body fluids, are also investigated. The review also discusses novel AIEgens used in the portable systems for the detection and monitoring of biomarkers in body fluid. Finally, the potential of future developments and the use of optical detection-based portable devices in healthcare activities are explored.

scholarly journals Epidemiological profile of Plasmodium ovale spp. imported from Africa to Anhui Province, China, 2012–2019

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Tao Zhang ◽  
Shuqi Wang ◽  
Duoquan Wang ◽  
Sarah Auburn ◽  
Shenning Lu ◽  
...  
Keyword(s):  
Information System ◽  
Disease Control ◽  
Latency Period ◽  
Anhui Province ◽  
Detection Methods ◽  
Health Concern ◽  
Plasmodium Ovale ◽  
Control And Prevention ◽  
Endemic Areas ◽  
Epidemiological Characteristics

Abstract Background Although autochthonous malaria cases are no longer reported in Anhui Province, China, imported malaria has become a major health concern. The proportion of reported malaria cases caused by Plasmodium ovale spp. increased to levels higher than expected during 2012 to 2019, and showed two peaks, 19.69% in 2015 and 19.35% in 2018. Methods A case-based retrospective study was performed using data collected from the China Information System for Disease Control and Prevention (CISDCP) and Information System for Parasitic Disease Control and Prevention (ISPDCP) from 2012 to 2019 to assess the trends and differences between Plasmodium ovale curtisi (P. o. curtisi) and Plasmodium ovale wallikeri (P. o. wallikeri). Epidemiological characteristics were analyzed using descriptive statistics. Results Plasmodium o. curtisi and P. o. wallikeri were found to simultaneously circulate in 14 African countries. Among 128 patients infected with P. ovale spp., the proportion of co-infection cases was 10.16%. Six cases of co-infection with P. ovale spp. and P. falciparum were noted, each presenting with two clinical attacks (the first attack was due to P. falciparum and the second was due to P. ovale spp.) at different intervals. Accurate identification of the infecting species was achieved among only 20.00% of cases of P. ovale spp. infection. At the reporting units, 32.17% and 6.96% of cases of P. ovale spp. infection were misdiagnosed as P. vivax and P. falciparum infections, respectively. Conclusion The present results indicate that the potential of P. ovale spp. to co-infect with other Plasmodium species has been previously underestimated, as is the incidence of P. ovale spp. in countries where malaria is endemic. P. o. curtisi may have a long latency period of > 3 years and potentially cause residual foci, thus posing challenges to the elimination of malaria in P. ovale spp.-endemic areas. Considering the low rate of species identification, more sensitive point-of-care detection methods need to be developed for P. ovale spp. and introduced in non-endemic areas.

scholarly journals Respiratory viral infections in the elderly

2021 ◽  
Vol 15 ◽  
pp. 175346662199505
Author(s):  
Alastair Watson ◽  
Tom M. A. Wilkinson
Keyword(s):  
Immune System ◽  
Viral Infections ◽  
Point Of Care ◽  
The Elderly ◽  
Respiratory Viruses ◽  
Morbidity And Mortality ◽  
Detection Methods ◽  
Respiratory Viral Infections ◽  
Tract Infections ◽  
Prolonged Hospital

With the global over 60-year-old population predicted to more than double over the next 35 years, caring for this aging population has become a major global healthcare challenge. In 2016 there were over 1 million deaths in >70 year olds due to lower respiratory tract infections; 13–31% of these have been reported to be caused by viruses. Since then, there has been a global COVID-19 pandemic, which has caused over 2.3 million deaths so far; increased age has been shown to be the biggest risk factor for morbidity and mortality. Thus, the burden of respiratory viral infections in the elderly is becoming an increasing unmet clinical need. Particular challenges are faced due to the interplay of a variety of factors including complex multimorbidities, decreased physiological reserve and an aging immune system. Moreover, their atypical presentation of symptoms may lead to delayed necessary care, prescription of additional drugs and prolonged hospital stay. This leads to morbidity and mortality and further nosocomial spread. Clinicians currently have limited access to sensitive detection methods. Furthermore, a lack of effective antiviral treatments means there is little incentive to diagnose and record specific non-COVID-19 viral infections. To meet this unmet clinical need, it is first essential to fully understand the burden of respiratory viruses in the elderly. Doing this through prospective screening research studies for all respiratory viruses will help guide preventative policies and clinical trials for emerging therapeutics. The implementation of multiplex point-of-care diagnostics as a mainstay in all healthcare settings will be essential to understand the burden of respiratory viruses, diagnose patients and monitor outbreaks. The further development of novel targeted vaccinations as well as anti-viral therapeutics and new ways to augment the aging immune system is now also essential. The reviews of this paper are available via the supplemental material section.

Diagnostic tests for detecting Chlamydia trachomatis and Neisseria gonorrhoeae in rectal and pharyngeal specimens

2021 ◽  
Author(s):  
Paul C. Adamson ◽  
Jeffrey D. Klausner
Keyword(s):  
Chlamydia Trachomatis ◽  
Neisseria Gonorrhoeae ◽  
Bacterial Infections ◽  
Point Of Care ◽  
High Sensitivity ◽  
Population Level ◽  
The United States ◽  
Nucleic Acid Amplification ◽  
Point Of Care Test ◽  
Control And Prevention

Chlamydia trachomatis and Neisseria gonorrhoeae are two of the most often reported bacterial infections in the United States. The rectum and oropharynx are important anatomic sites of infection and can contribute to ongoing transmission. Nucleic acid amplification tests (NAATs) are the mainstays for the detection of C. trachomatis and N. gonorrhoeae infections owing to their high sensitivity and specificity. Several NAATs have been evaluated for testing in rectal and pharyngeal infections. A few assays recently received clearance by the Food and Drug Administration, including one point-of-care test. Those assays can be used for testing in symptomatic individuals, as well as for asymptomatic screening in certain patient populations. Routine screening for C. trachomatis in pharyngeal specimens is not recommended by the Centers for Disease Control and Prevention, though is often performed due to the use of multiplex assays. While expanding the types of settings for screening and using self-collected rectal and pharyngeal specimens can help to increase access and uptake of testing, additional research is needed to determine the potential benefits and costs associated with increased screening for rectal and pharyngeal C. trachomatis and N. gonorrhoeae infections on a population level.

Evaluation of Human Fecal Calprotectin Detection Kits and Their Potential use as Non-Invasive Intestinal Biomarker of Infectious Enterocolitis in Pigs

2021 ◽  
Author(s):  
Jéssica Barbosa ◽  
Lucas Rodrigues ◽  
Daniel Columbus ◽  
Juan Aguirre ◽  
John Harding ◽  
...  
Keyword(s):  
Intestinal Inflammation ◽  
Point Of Care ◽  
Sandwich Elisa ◽  
Fecal Calprotectin ◽  
Field Application ◽  
Dipstick Test ◽  
Infectious Colitis ◽  
Fecal Samples ◽  
Non Invasive ◽  
Infectious Enterocolitis

Abstract Background: Fecal calprotectin is largely applied as a non-invasive intestinal inflammation biomarker in human medicine. Previous studies in pigs investigated the levels of fecal calprotectin in healthy animals only. Thus, there is a knowledge gap regarding its application during infectious diarrhea. This study investigated the usefulness of fecal calprotectin as a biomarker of intestinal inflammation in Brachyspira hyodysenteriae and Salmonella Typhimurium infected pigs. Results: Fecal samples from pigs with colitis (n=18) were collected from animals experimentally inoculated with B. hyodysenteriae G44 or from sham-inoculated controls. Fecal samples from pigs with enteritis (n=14) were collected from animals inoculated with Salmonella enterica serovar Typhimurium or from sham-inoculated controls. For both groups, fecal samples were scored as: 0 = normal; 1 = soft, wet cement; 2 = watery feces; 3 = mucoid diarrhea; and 4 = bloody diarrhea. Fecal calprotectin levels were assayed using a sandwich ELISA, a turbidimetric immunoassay and a point-of-care dipstick test. Fecal calprotectin levels were greater in colitis samples scoring 4 versus ≤ 4 using ELISA, and in feces scoring 3 and 4 versus ≤ 1 using immunoturbidimetry (P < 0.05). No differences were found in calprotectin concentration among fecal scores for enteritis samples, regardless of the assay used. All samples were found below detection limits using the dipstick method.Conclusions: Fecal calprotectin is a potential non-invasive biomarker of infectious colitis, but it is not suitable for detection of enteritis. While practical, the use of commercially available human presents sensitivity limitations. Further studies are needed to validate the field application of calprotectin as a marker.

scholarly journals Schistosomiasis: from established diagnostic assays to emerging micro/nanotechnology-based rapid field testing for clinical management and epidemiology

2019 ◽  
Vol 3 (1) ◽  
pp. 439-458 ◽  
Author(s):  
Maurice Mutro Nigo ◽  
Georgette Salieb-Beugelaar ◽  
Manuel Battegay ◽  
Peter Odermatt ◽  
Patrick Hunziker
Keyword(s):  
Point Of Care ◽  
Field Testing ◽  
Detection Methods ◽  
Low Grade ◽  
Analytical Strategy ◽  
Diagnostic Assays ◽  
And Control ◽  
Analytical Platforms ◽  
Selection Of

Schistosomiasis is a neglected invasive worm disease with a huge disease burden in developing countries, particularly in children, and is seen increasingly in non-endemic regions through transfer by travellers, expatriates, and refugees. Undetected and untreated infections may be responsible for the persistence of transmission. Rapid and accurate diagnosis is the key to treatment and control. So far, parasitological detection methods remain the cornerstone of Schistosoma infection diagnosis in endemic regions, but conventional tests have limited sensitivity, in particular in low-grade infection. Recent advances contribute to improved detection in clinical and field settings. The recent progress in micro- and nanotechnologies opens a road by enabling the design of new miniaturized point-of-care devices and analytical platforms, which can be used for the rapid detection of these infections. This review starts with an overview of currently available laboratory tests and their performance and then discusses emerging rapid and micro/nanotechnologies-based tools. The epidemiological and clinical setting of testing is then discussed as an important determinant for the selection of the best analytical strategy in patients suspected to suffer from Schistosoma infection. Finally, it discusses the potential role of advanced technologies in the setting near to disease eradication is examined.

scholarly journals Multiplexed Detection of Sepsis Markers in Whole Blood using Nanocomposite Coated Electrochemical Sensors

2020 ◽  
Author(s):  
Uroš Zupančič ◽  
Pawan Jolly ◽  
Pedro Estrela ◽  
Despina Moschou ◽  
Donald E. Ingber
Keyword(s):  
Electrochemical Detection ◽  
Whole Blood ◽  
Electrochemical Sensors ◽  
Point Of Care ◽  
Sample Volume ◽  
Nanocomposite Coating ◽  
Cross Reactivity ◽  
Detection Methods ◽  
Clinical Samples ◽  
Undiluted Serum

ABSTRACTSepsis is a leading cause of mortality worldwide that is difficult to diagnose and manage because this requires simultaneous analysis of multiple biomarkers. Electrochemical detection methods could potentially provide a way to accurately quantify multiple sepsis biomarkers in a multiplexed manner as they have very low limits of detection and require minimal sensor instrumentation; however, affinity-based electrochemical sensors are usually hampered by biological fouling. Here we describe development of an electrochemical detection platform that enables detection of multiple sepsis biomarkers simultaneously by incorporating a recently developed nanocomposite coating composed of crosslinked bovine serum albumin containing a network of reduced graphene oxide nanoparticles that prevents biofouling. Using nanocomposite coated planar gold electrodes, we constructed a procalcitonin sensor and demonstrated sensitive PCT detection in undiluted serum and clinical samples, as well as excellent correlation with a conventional ELISA (adjusted r2 = 0.95). Sensors for two additional sepsis biomarkers — C-reactive protein and pathogen-associated molecular patterns — were developed on the same multiplexed platform and tested in whole blood. Due to the excellent antifouling properties of the nanocomposite coating, all three sensors exhibited specific responses within the clinically significant range without any cross-reactivity in the same channel with low sample volume. This platform enables sensitive simultaneous electrochemical detection of multiple analytes in human whole blood, which can be expanded further to any target analyte with an appropriate antibody pair or capturing probe, and thus, may offer a potentially valuable tool for development of clinical point-of-care diagnostics.GRAPHICAL ABSTRACT

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