Screening Methods for Catalytic Antibodies

The practice of systematic examinations in hospitals and the increasing development of automatic data processing permits the storing of a great deal of information about a large number of patients belonging to different diagnosis groups.To predict or to characterize these diagnosis groups some descriptors are particularly useful, others carry no information. Data screening based on the properties of mutual information and on the log cross products ratios in contingency tables is developed. The most useful descriptors are selected. For each one the characterized groups are specified.This approach has been performed on a set of binary (presence—absence) radiological variables. Four diagnoses groups are concerned: cancer of pancreas, chronic calcifying pancreatitis, non-calcifying pancreatitis and probable pancreatitis. Only twenty of the three hundred and forty initial radiological variables are selected. The presence of each corresponding sign is associated with one or more diagnosis groups.

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Rapid Screening Methods for Bleeding Disorders. A Three Year Survey

Thrombosis and Haemostasis ◽

10.1055/s-0038-1654846 ◽

1964 ◽

Vol 11 (02) ◽

pp. 506-512 ◽

Cited By ~ 1

Author(s):

V. A Lovric ◽

J Margolis

Keyword(s):

Laboratory Tests ◽

Capillary Blood ◽

Screening Tests ◽

Rapid Screening ◽

Screening Methods ◽

Bleeding Disorders ◽

Routine Laboratory ◽

Clotting Time ◽

Kaolin Clotting Time ◽

In Infants And Children

SummaryAn adaptation of “kaolin clotting time” and prothrombin time for use on haemolysed capillary blood provided simple and sensitive screening tests suitable for use in infants and children. A survey of three year’s experience shows that these are reliable routine laboratory tests for detection of latent coagulation disorders.

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Proposal for Objective Evaluation of the Performance of Various Functional APC-resistance Tests in Genotyped Patients

Thrombosis and Haemostasis ◽

10.1055/s-0038-1665412 ◽

1997 ◽

Vol 78 (05) ◽

pp. 1360-1365 ◽

Cited By ~ 10

Author(s):

G Freyburger ◽

S Javorschi ◽

S Labrouche ◽

P Bernard

Keyword(s):

Protein S ◽

Objective Evaluation ◽

Original Method ◽

Screening Methods ◽

Factor Xii ◽

Factor V ◽

Likelihood Ratios ◽

Modified Method ◽

Apc Resistance ◽

Two Parameters

SummaryThe aim of the present study was to evaluate the relative performance of five screening methods for APC resistance caused by the factor V:Q506 mutation: the original method Coatest® APC™ Resistance Chromogenix, a modified method using the same reagents but a predilution 1+4 of the plasma in a factor V deficient plasma from Stago (Stago deficient V) or from Chromogenix (V-DEF Plasma), the Coatest® APC™ Resistance V (Chromogenix), and Accelerimat™ from bioMérieux. Normalization was done against a pool of normal plasmas for the methods from Chromogenix. The study included 350 subjects, 219 were genotyped (174 FV:R506R, 42 FV:Q506R, 3 FV:Q506Q) and most of them were assessed by more than one method. Uncertainty in predicting the FV genotype was evaluated by statistical analysis, which provided a way to quantitate the performance of the different diagnostic approaches. Performance of each test was evaluated by its sensitivity, specificity, R.O.C. curves, positive and negative likelihood ratios (LR), and the overall performance was determined by two parameters derived from the LR curves : the maximum LR value obtained at the crossover of the two curves, and the distance between the two curves for LR = 10. Coatest® APC™ Resistance V and Accelerimat™ were proven to be the methods most able to discriminate for factor V:Q506, while normalization was not shown to improve the screening performance. The original method from Chromogenix was confirmed to undergo many influences (factor XII, PAI-1, thrombin- antithrombin complexes, antithrombin III, hematocrit). Although a very good improvement was provided by the newest methods, they were shown to be influenced by protein S and/or factor V levels in the sample plasma.

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Non-Invasive Distinction of Non-Alcoholic Fatty Liver Disease using Urinary Volatile Organic Compound Analysis: Early Results

Journal of Gastrointestinal and Liver Diseases ◽

10.15403/jgld.2014.1121.242.ury ◽

2015 ◽

Vol 24 (2) ◽

pp. 197-201 ◽

Cited By ~ 10

Author(s):

Ramesh P. Arasaradnam ◽

Michael McFarlane ◽

Emma Daulton ◽

Erik Westenbrink ◽

Nicola O’Connell ◽

...

Keyword(s):

Liver Disease ◽

Pilot Study ◽

Fatty Liver ◽

Fatty Liver Disease ◽

Diagnostic Methods ◽

Screening Methods ◽

Alcoholic Fatty Liver ◽

Non Invasive ◽

Volatile Organic ◽

Alcoholic Fatty Liver Disease

Background & Aims: Non-Alcoholic Fatty Liver Disease (NAFLD) is the commonest cause of chronic liver disease in the western world. Current diagnostic methods including Fibroscan have limitations, thus there is a need for more robust non-invasive screening methods. The gut microbiome is altered in several gastrointestinal and hepatic disorders resulting in altered, unique gut fermentation patterns, detectable by analysis of volatile organic compounds (VOCs) in urine, breath and faeces. We performed a proof of principle pilot study to determine if progressive fatty liver disease produced an altered urinary VOC pattern; specifically NAFLD and Non-Alcoholic Steatohepatitis (NASH).Methods: 34 patients were recruited: 8 NASH cirrhotics (NASH-C); 7 non-cirrhotic NASH; 4 NAFLD and 15 controls. Urine was collected and stored frozen. For assay, the samples were defrosted and aliquoted into vials, which were heated to 40±0.1°C and the headspace analyzed by FAIMS (Field Asymmetric Ion Mobility Spectroscopy). A previously used data processing pipeline employing a Random Forrest classification algorithm and using a 10 fold cross validation method was applied.Results: Urinary VOC results demonstrated sensitivity of 0.58 (0.33 - 0.88), but specificity of 0.93 (0.68 - 1.00) and an Area Under Curve (AUC) 0.73 (0.55 -0.90) to distinguish between liver disease and controls. However, NASH/NASH-C was separated from the NAFLD/controls with a sensitivity of 0.73 (0.45 - 0.92), specificity of 0.79 (0.54 - 0.94) and AUC of 0.79 (0.64 - 0.95), respectively.Conclusions: This pilot study suggests that urinary VOCs detection may offer the potential for early non-invasive characterisation of liver disease using 'smell prints' to distinguish between NASH and NAFLD.

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Prevention of Preterm Birth

Journal of Biomedical and Clinical Research ◽

10.2478/jbcr-2018-0013 ◽

2018 ◽

Vol 11 (2) ◽

pp. 95-104

Author(s):

Ivan D. Ivanov ◽

Stefan A. Buzalov ◽

Nadezhda H. Hinkova

Keyword(s):

Risk Factors ◽

Preterm Birth ◽

High Risk ◽

Medical Science ◽

Secondary Prophylaxis ◽

High Risk Group ◽

Screening Methods ◽

Perinatal Complications ◽

Social Significance ◽

Neonatal Deaths

Summary Preterm birth (PTB) is a worldwide problem with great social significance because it is a leading cause of perinatal complications and perinatal mortality. PTB is responsible for more than a half of neonatal deaths. The rate of preterm delivery varies between 5-18% worldwide and has not decreased in recent years, regardless of the development of medical science. One of the leading causes for that is the failure to identify the high-risk group in prenatal care. PTB is a heterogeneous syndrome in which many different factors interfere at different levels of the pathogenesis of the initiation of delivery, finally resulting in delivery before 37 weeks of gestation (wg). The various specificities of risk factors and the unclear mechanism of initiation of labour make it difficult to elaborate standard, unified and effective screening to diagnose pregnant women at high-risk for PTB correctly. Furthermore, they make primary and secondary prophylaxis less effective and render diagnostic and therapeutic measures ineffective and inappropriate. Reliable and accessible screening methods are necessary for antenatal care, and risk factors for PTB should be studied and clarified in search of useful tools to solve issues of risk pregnancies to decrease PTB rates and associated complications.

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Tuning the Redox Activity of Metal−Organic Frameworks for Enhanced, Selective O2 Binding

10.26434/chemrxiv.10316681.v1 ◽

2019 ◽

Author(s):

Andrew Rosen ◽

M. Rasel Mian ◽

Timur Islamoglu ◽

Haoyuan Chen ◽

Omar Farha ◽

...

Keyword(s):

Density Functional ◽

Metal Organic Frameworks ◽

Redox Activity ◽

Screening Methods ◽

Bridging Ligands ◽

Metal Centers ◽

Computational Screening ◽

Open Metal Sites ◽

Metal Organic ◽

Unsaturated Metal Sites

Metal−organic frameworks (MOFs) with coordinatively unsaturated metal sites are appealing as adsorbent materials due to their tunable functionality and ability to selectively bind small molecules. Through the use of computational screening methods based on periodic density functional theory, we investigate O2 and N2 adsorption at the coordinatively unsaturated metal sites of several MOF families. A variety of design handles are identified that can be used to modify the redox activity of the metal centers, including changing the functionalization of the linkers (replacing oxido donors with sulfido donors), anion exchange of bridging ligands (considering μ-Br-, μ-Cl-, μ-F-, μ-SH-, or μ-OH- groups), and altering the formal oxidation state of the metal. As a result, we show that it is possible to tune the O2 affinity at the open metal sites of MOFs for applications involving the strong and/or selective binding of O2. In contrast with O2 adsorption, N2 adsorption at open metal sites is predicted to be relatively weak across the MOF dataset, with the exception of MOFs containing synthetically elusive V2+ open metal sites. As one example from the screening study, we predict that exchanging the μ-Cl- ligands of M2Cl2(BBTA) (H2BBTA = 1H,5H-benzo(1,2-d:4,5-d′)bistriazole) with μ-OH- groups would significantly enhance the strength of O2 adsorption at the open metal sites without a corresponding increase in the N2 affinity. Experimental investigation of Co2Cl2(BBTA) and Co2(OH)2(BBTA) confirms that the former exhibits only weak physisorption, whereas the latter is capable of chemisorbing O2 at room temperature. The chemisorption behavior is attributed to the greater electron-donating character of the μ-OH- ligands and the presence of H-bonding interactions between the μ-OH- bridging ligands and the O2 adsorbate.

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Antibody Screening Results for Anti-Nucleocapsid Antibodies Towards the Development of a SARS-CoV-2 Nucleocapsid Protein Antigen Detecting Lateral Flow Assay

10.26434/chemrxiv.12709538 ◽

2021 ◽

Author(s):

David Cate ◽

Helen Hsieh ◽

Veronika Glukhova ◽

Joshua D Bishop ◽

H Gleda Hermansky ◽

...

Keyword(s):

Nucleocapsid Protein ◽

Point Of Care ◽

Lateral Flow ◽

Screening Methods ◽

Antibody Screening ◽

Liquid Handling ◽

Large Numbers ◽

Accurate Performance ◽

Further Development ◽

Assay Conditions

The global COVID-19 pandemic has created an urgent demand for large numbers of inexpensive, accurate, rapid, point-of-care diagnostic tests. Analyte-based assays are suitably inexpensive and can be rapidly mass-produced, but for sufficiently accurate performance they require highly optimized antibodies and assay conditions. We used an automated liquid handling system, customized to handle arrays of lateral flow immunoassay (LFA) tests in a high-throughput screen, to identify anti-nucleocapsid antibodies that will perform optimally in an LFA. We tested 1021 anti-nucleocapsid antibody pairs as LFA capture and detection reagents with the goal of highlighting pairs that have the greatest affinity for unique epitopes of the nucleocapsid protein of SARS-CoV-2 within the LFA format. In contrast to traditional antibody screening methods (e.g., ELISA, bio-layer interferometry), the method described here integrates real-time reaction kinetics with transport in, and immobilization directly onto, nitrocellulose. We have identified several candidate antibody pairs that are suitable for further development of an LFA for SARS-CoV-2.

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