scholarly journals Electrochemical nanobiosensors perspectives for COVID 19 pandemic

2021 ◽  
Author(s):  
Rajshri Kundlik Satvekar
Keyword(s):  
High Reliability ◽  
Low Cost ◽  
Virus Detection ◽  
Research Area ◽  
Diagnostic Techniques ◽  
Diagnostic Methods ◽  
High Throughput Analysis ◽  
Diagnostic Practices ◽  
Polymerase Chain ◽  
High Degree

Early, rapid and ultrasensitive diagnosis of COVID-19 to facilitate high-throughput analysis without a high degree of technical expertise or sophisticated equipment is necessary to expand COVID-19 testing capability. Leveraging interdisciplinary proficiency in analytical chemistry, biomedical instrumentation, molecular biology, microfluidics, and nanotechnology, considerable advances have been made to develop a novel diagnostic tool that assures superior key performances for COVID-19 diagnosis. This review summarizes the nano-enabled systems such as electrochemical nanobiosensor for SARS-CoV-2 virus detection and emphasizes promising diagnostic techniques to extensively facilitate the diagnostic practices during the COVID-19 pandemic. Currently, three main diagnostic methods have been widely used in the COVID-19 pandemic: nucleic acid (NA)-based testing, computed tomography (CT), and serological testing. NA-based detection of SARS-CoV-2 such as Reverse transcription polymerase chain reaction has become the gold standard for COVID-19 diagnosis. This review congregates significant contributions in the electrochemical nanobiosensor research area, which is helpful for further nanobiosensor development. Although many efforts were taken to detect the SARS-CoV-2, the COVID 19 diagnosis still relies on expensive prolonged analysis. A rapid and reliable alternative is the utilization of a low-cost nanobiosensor for SARS-CoV-2 detection that can rapidly diagnose the disease even in asymptomatic conditions with high reliability and sensitivity.

Influence of euthanasia, the intensity of inflammatory lesion and viral load in the laboratory diagnosis of rabies in cattle

2021 ◽  
Vol 41 ◽  
Author(s):  
Claudia S. Wisser ◽  
Marcélia E.S. Fernandes ◽  
Elaine Melchioretto ◽  
Daiane Ogliari ◽  
Aldo Gava ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
Viral Load ◽  
Inflammatory Lesion ◽  
Diagnostic Techniques ◽  
Diagnostic Methods ◽  
Chain Reaction ◽  
Qrt Pcr ◽  
Clinical Evolution ◽  
Early Stages ◽  
Polymerase Chain

ABSTRACT: This research reports the use of different diagnostic tests in cattle, naturally infected by Rabies lyssavirus (RABV), and correlates the positivity of the tests with the clinical moment of euthanasia, the intensity of the inflammatory lesion and viral load. It also highlights the possibility of euthanasia in early stages of the disease as a way to improve animal welfare. For that, samples of 34 bovine brains were collected for analysis, preserved in 10% buffered formaline and refrigerated with subsequent freezing. The samples were subjected to direct immunofluorescence antibody technique (DFAT) tests, viral isolation in cell culture (VICC), histopathology with hematoxylin and eosin staining (HE), immunohistochemistry (IHC), Shorr stainied neural tissue smears (DSS), Reverse transcription polymerase chain reaction (RT-PCR) and polymerase chain reaction by quantitative reverse transcriptase (qRT-PCR). The areas used for analysis were the cerebellum, parietal telencephalon and thalamus. Samples with Negri bodies (NBs) or immunostaining in at least one of the analyzed areas were considered positive. For the study of the intensity of histological lesions, the lesions were classified into grades 0, 1, 2 and 3 and the positivity of the test in the presence or absence of NBs in one of the three areas analyzed. To verify the influence of the disease clinical evolution, 4-four groups of analysis were created according to the animal’s clinical status at moment of the euthanasia, being: M1 = animal euthanized while standing, M2 = euthanized when in sternal recumbence, M3 = euthanized when in lateral recumbence, M4 = animal with natural death. Of the 34 brains evaluated, IHC was positive in 100% of cases, DFAT was positive in 97.05% of them, and in this negative sample the presence of RABV was confirmed by VICC. NBs ere seen in 88.23% of the cases, and the DSS test was positive in 82.35% of them. All diagnostic techniques showed positive cases in all groups analyzed. Each case was positive in at least two diagnostic methods. All cases that contained NBs were positive for rabies in the other tests. In this study, it was observed that the variables analyzed (intensity of injury and clinical evolution at the moment of euthanasia) had an influence only on HE and DSS techniques, which are based on NB research to form the diagnosis, but did not interfere with the effectiveness of the diagnosis performed by detecting the viral antigen performed by DFAT and IHC. All isolated RABV samples included in the present study have a genetic lineage characteristic of hematophagous bats Desmodus rotundus. The evaluation of qRT-PCR showed that the amount of virus did not interfere in the positivity of the tests. This work shows that IHC and DFAT are safe diagnostic techniques. They are capable of detecting RABV even in euthanized animals in the early stages of clinical evolution with mild intensities of histological lesions.

scholarly journals Further Evidence of Inadequate Quality in Lateral Flow Devices Commercially Offered for the Diagnosis of Rabies

2020 ◽  
Vol 5 (1) ◽  
pp. 13 ◽  
Author(s):  
Antonia Klein ◽  
Anna Fahrion ◽  
Stefan Finke ◽  
Marina Eyngor ◽  
Shiri Novak ◽  
...  
Keyword(s):  
Low Cost ◽  
Diagnostic Techniques ◽  
Medical Intervention ◽  
Lateral Flow ◽  
Diagnostic Methods ◽  
Diagnostic Tools ◽  
Middle Income ◽  
Human Contact ◽  
The One ◽  
Flow Devices

As a neglected zoonotic disease, rabies causes approximately 5.9 × 104 human deaths annually, primarily affecting low- and middle-income countries in Asia and Africa. In those regions, insufficient surveillance is hampering adequate medical intervention and is driving the vicious cycle of neglect. Where resources to provide laboratory disease confirmation are limited, there is a need for user-friendly and low-cost reliable diagnostic tools that do not rely on specialized laboratory facilities. Lateral flow devices (LFD) offer an alternative to conventional diagnostic methods and may strengthen control efforts in low-resource settings. Five different commercially available LFDs were compared in a multi-centered study with respect to their diagnostic sensitivity and their agreement with standard rabies diagnostic techniques. Our evaluation was conducted by several international reference laboratories using a broad panel of samples. The overall sensitivities ranged from 0% up to 62%, depending on the LFD manufacturer, with substantial variation between the different laboratories. Samples with high antigen content and high relative viral load tended to test positive more often in the Anigen/Bionote test, the latter being the one with the best performance. Still, the overall unsatisfactory findings corroborate a previous study and indicate a persistent lack of appropriate test validation and quality control. At present, the tested kits are not suitable for in-field use for rabies diagnosis, especially not for suspect animals where human contact has been identified, as an incorrect negative diagnosis may result in human casualties. This study points out the discrepancy between the enormous need for such a diagnostic tool on the one hand, and on the other hand, a number of already existing tests that are not yet ready for use.

scholarly journals A Complete Protocol for Rapid and Low-Cost Fabrication of Polymer Microfluidic Chips Containing Three-Dimensional Microstructures Used in Point-of-Care Devices

Micromachines ◽  
2019 ◽  
Vol 10 (9) ◽  
pp. 624 ◽  
Author(s):  
Trieu Nguyen ◽  
Aaydha Chidambara Vinayaka ◽  
Dang Duong Bang ◽  
Anders Wolff
Keyword(s):  
Salmonella Enteritidis ◽  
Solid Phase ◽  
Point Of Care ◽  
Low Cost ◽  
Three Dimensional ◽  
Diagnostic Methods ◽  
Molecular Diagnostic ◽  
Microfluidic Chips ◽  
Industrial Companies ◽  
Polymerase Chain

This protocol provides insights into the rapid, low-cost, and largescale fabrication of polymer microfluidic chips containing three-dimensional microstructures used in point-of-care devices for applications such as detection of pathogens via molecular diagnostic methods. The details of the fabrication methods are described in this paper. This study offers suggestions for researchers and experimentalists, both at university laboratories and in industrial companies, to prevent doom fabrication issues. For a demonstration of bio-application in point-of-care testing, the 3D microarrays fabricated are then employed in multiplexed detection of Salmonella (Salmonella Typhimurium and Salmonella Enteritidis), based on a molecular detection technique called solid-phase polymerase chain reaction (SP-PCR).

scholarly journals The Role of Molecular Tests in the Diagnosis of Disseminated Histoplasmosis

2019 ◽  
Vol 6 (1) ◽  
pp. 1 ◽  
Author(s):  
Izadora Clezar da Silva Vasconcellos ◽  
Daiane Flores Dalla Lana ◽  
Alessandro C. Pasqualotto
Keyword(s):  
Severe Infection ◽  
Diagnostic Techniques ◽  
Antigen Detection ◽  
Diagnostic Methods ◽  
Clinical Samples ◽  
Molecular Tests ◽  
Disseminated Histoplasmosis ◽  
Satisfactory Performance ◽  
Polymerase Chain

Histoplasmosis is an emerging fungal disease, with global distribution. The disseminated form of the disease is a more severe infection, generally associated with AIDS. Classic diagnostic methods for histoplasmosis consist of microscopy, culture, and histopathology. More recently, the importance of Histoplasma antigen detection has dominated the literature on histoplasmosis diagnosis, but the relevance of molecular assays has not been as much studied. Here we describe the results of a systematic literature review focusing on studies that mainly compared immunological techniques (Histoplasma urine antigen detection) with molecular tests for the diagnosis of histoplasmosis. In addition to the review of comparative studies using such diagnostic techniques, the literature on polymerase chain reaction (PCR) tests in patients with disseminated histoplasmosis is also summarized. Two studies reported the comparison between immunological and molecular methods applied simultaneously for the diagnosis of disseminated histoplasmosis. PCR demonstrates a satisfactory performance assisting in the detection of Histoplasma spp. DNA in clinical samples.

scholarly journals RT-LAMP CRISPR-Cas12/13-Based SARS-CoV-2 Detection Methods

Diagnostics ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1646
Author(s):  
Kasturi Selvam ◽  
Mohamad Ahmad Najib ◽  
Muhammad Fazli Khalid ◽  
Suharni Mohamad ◽  
Fahreddin Palaz ◽  
...  
Keyword(s):  
Reverse Transcription ◽  
Quantitative Polymerase Chain Reaction ◽  
Diagnostic Techniques ◽  
Diagnostic Methods ◽  
Detection Methods ◽  
Molecular Diagnostic ◽  
Public Attention ◽  
Laboratory Equipment ◽  
Highly Sensitive ◽  
Polymerase Chain

Coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has attracted public attention. The gold standard for diagnosing COVID-19 is reverse transcription–quantitative polymerase chain reaction (RT-qPCR). However, RT-qPCR can only be performed in centralized laboratories due to the requirement for advanced laboratory equipment and qualified workers. In the last decade, clustered regularly interspaced short palindromic repeats (CRISPR) technology has shown considerable promise in the development of rapid, highly sensitive, and specific molecular diagnostic methods that do not require complicated instrumentation. During the current COVID-19 pandemic, there has been growing interest in using CRISPR-based diagnostic techniques to develop rapid and accurate assays for detecting SARS-CoV-2. In this work, we review and summarize reverse-transcription loop-mediated isothermal amplification (RT-LAMP) CRISPR-based diagnostic techniques for detecting SARS-CoV-2.

The Physician’s Task and the Problem of Documentation

1964 ◽  
Vol 03 (01) ◽  
pp. 11-19 ◽  
Author(s):  
A. Proppe
Keyword(s):  
Statistical Evaluation ◽  
Age Groups ◽  
Diagnostic Methods ◽  
Early Age ◽  
Case Histories ◽  
Lupus Vulgaris ◽  
Pathological Conditions ◽  
Clinical Methods ◽  
Corpus Hippocraticum ◽  
High Degree

SummaryCase histories suitable for statistical evaluation can be found even as far back as in the Corpus Hippocraticum. Such simple data as the patient’s age, body weight, size, the date of menarche, etc. are practically always included in the case records, and it is demonstrated that, when such data are recorded in a system of documentation suitable for mechanical sorting, it may enable us to draw conclusions of very great importance. Mechanical registration methods have revealed that, in the determination and recording of data as hitherto carried out. there has been a surprisingly large number of errors and a high degree of unreliability. This view has a considerable influence on modern clinical methods; it renders a more democratic relation between physician and patient necessary and makes clear the need for measures to enhance the reliability of diagnosis and treatment of pathological conditions. The author illustrates this view with reference to the mechanical falsification of the thesis of the proneness of early age groups to lupus vulgaris, furthermore with reference to the mechanical rationalization of modern routine diagnostic methods, to the constant surveillance of adverse effects on public health and to the protection against allergic reactions with the aid of recording systems of personal allergy and intolerance data with mechanical sorting and computer techniques.

Fuzzy multi-objective location and routing problem

2020 ◽  
Vol 39 (3) ◽  
pp. 3259-3273
Author(s):  
Nasser Shahsavari-Pour ◽  
Najmeh Bahram-Pour ◽  
Mojde Kazemi
Keyword(s):  
Firefly Algorithm ◽  
High Reliability ◽  
Research Area ◽  
Nsga Ii ◽  
Location Routing Problem ◽  
Routing Problem ◽  
Location Allocation ◽  
Multi Objective ◽  
Location Routing ◽  
The Cost

The location-routing problem is a research area that simultaneously solves location-allocation and vehicle routing issues. It is critical to delivering emergency goods to customers with high reliability. In this paper, reliability in location and routing problems was considered as the probability of failure in depots, vehicles, and routs. The problem has two objectives, minimizing the cost and maximizing the reliability, the latter expressed by minimizing the expected cost of failure. First, a mathematical model of the problem was presented and due to its NP-hard nature, it was solved by a meta-heuristic approach using a NSGA-II algorithm and a discrete multi-objective firefly algorithm. The efficiency of these algorithms was studied through a complete set of examples and it was found that the multi-objective discrete firefly algorithm has a better Diversification Metric (DM) index; the Mean Ideal Distance (MID) and Spacing Metric (SM) indexes are only suitable for small to medium problems, losing their effectiveness for big problems.

Forensic research of staff fraud

2020 ◽  
Vol 23 (5) ◽  
pp. 585-600
Author(s):  
V.A. Timchenko
Keyword(s):  
Effective Means ◽  
Criminal Activity ◽  
Diagnostic Techniques ◽  
Scientific Basis ◽  
Diagnostic Methods ◽  
Structural Units ◽  
Forensic Research ◽  
Economic Information ◽  
Commercial Organizations ◽  
Original Approach

Subject. This article deals with the issues of forensic diagnostics, which is an effective means of detecting, preventing and suppressing staff fraud. Objectives. The article aims to present an original approach to the development of methods of forensic diagnosis of staff fraud based on the modeling method. It is also intended to identify a structure of staff fraud patterns and justify the need to classify the staff fraud methods. Methods. For the study, I used the methods of comparative analysis, systematization, induction, and deduction. Results. The article defines approaches to the formation of diagnostic methods of staff fraud and presents typical inconsistencies that arise in economic information under the influence of fraudulent actions of staff. It describes some diagnostic techniques that can detect staff fraud elements that occur in certain ways of criminal activity. Conclusions and Relevance. The proposed original approach helps develop standard and specific methods for diagnosing staff fraud on a scientific basis. The provisions outlined in the article can serve as a basis for scholarly discussion, contribute to the effectiveness of research on counter-fraud in the field of personnel fraud, and can be applied to the practical activities of structural units and individuals whose task is to combat staff fraud in commercial organizations.

Modelling of bacterial removal in wastewater storage reservoir for irrigation purposes: a case study in Sicily, Italy

2003 ◽  
Vol 3 (4) ◽  
pp. 169-175 ◽  
Author(s):  
S. Barbagallo ◽  
F. Brissaud ◽  
G.L. Cirelli ◽  
S. Consoli ◽  
P. Xu
Keyword(s):  
Municipal Wastewater ◽  
High Reliability ◽  
Low Cost ◽  
Public Awareness ◽  
Storage System ◽  
Wastewater Reuse ◽  
Order Kinetic ◽  
Aquifer Recharge ◽  
Mediterranean Countries ◽  
Storage Reservoirs

In arid and semiarid regions the reclamation and reuse of municipal wastewater can play a strategic role in alleviating water resources shortages. Public awareness is growing about the need to recycle and reuse water for increasing supply availability. Many wastewater reuse projects have been put in operation in European and Mediterranean countries adopting extensive treatment systems such as aquifer recharge, lagooning, constructed wetlands, and storage reservoirs, mainly for landscape and agricultural irrigation. In agricultural reuse systems, there is an increasing interest in extensive technologies because of their high reliability, and easy and low cost operation and maintenance. Wastewater storage reservoirs have become the option selected in many countries because of the advantages they present in comparison with other treatment alternatives, namely the coupling of two purposes, stabilization and seasonal regulation. This paper describes an example of a wastewater storage system, built in Caltagirone (Sicily, Italy). The storage results in a tertiary treatment of a continuous inlet flow of activated sludge effluents. The prediction of the microbiological water quality has been evaluated by means of a non-steady-state first-order kinetic model. Single and multiple regressions were applied to determine the main variables that most significantly affected die-off coefficients. The proposed model has been calibrated using the results of a field monitoring carried out during a period from March to October 2000.

scholarly journals Application of Oxford Nanopore Technology to Plant Virus Detection

Viruses ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1424
Author(s):  
Lia W. Liefting ◽  
David W. Waite ◽  
Jeremy R. Thompson
Keyword(s):  
Plant Virus ◽  
High Throughput Sequencing ◽  
Virus Detection ◽  
Diagnostic Methods ◽  
Plant Virus Detection ◽  
Sequencing Technologies ◽  
Oxford Nanopore ◽  
Virus Diagnostics ◽  
Post Entry ◽  
Read Accuracy

The adoption of Oxford Nanopore Technologies (ONT) sequencing as a tool in plant virology has been relatively slow despite its promise in more recent years to yield large quantities of long nucleotide sequences in real time without the need for prior amplification. The portability of the MinION and Flongle platforms combined with lowering costs and continued improvements in read accuracy make ONT an attractive method for both low- and high-scale virus diagnostics. Here, we provide a detailed step-by-step protocol using the ONT Flongle platform that we have developed for the routine application on a range of symptomatic post-entry quarantine and domestic surveillance plant samples. The aim of this methods paper is to highlight ONT’s feasibility as a valuable component to the diagnostician’s toolkit and to hopefully stimulate other laboratories towards the eventual goal of integrating high-throughput sequencing technologies as validated plant virus diagnostic methods in their own right.

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