Simple and rapid screening methods for microorganisms with phospholipase A1, A2 and C activities

1994 ◽  
Vol 8 (9) ◽  
Author(s):  
MyungKee Kim ◽  
JoonShick Rhee
Keyword(s):  
Rapid Screening ◽  
Screening Methods ◽  
Phospholipase A1

Rapid Screening Methods for Bleeding Disorders. A Three Year Survey

1964 ◽  
Vol 11 (02) ◽  
pp. 506-512 ◽  
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.

Development of New Geopolymer-Based System for Challenging Well Conditions

2021 ◽  
Author(s):  
Siti Humairah Abd Rahman ◽  
Anatoly Medvedev ◽  
Andrey Yakovlev ◽  
Yon Azwa Sazali ◽  
Bipin Jain ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Fly Ash ◽  
Construction Industry ◽  
Raw Materials ◽  
Critical Role ◽  
Acid Resistance ◽  
Oil Industry ◽  
Rapid Screening ◽  
Fluid Loss ◽  
Screening Methods

Abstract With the development of new oil formations and with the advent of new directions in the global energy sector, new requirements for materials for well construction appear. With the close attention to environmental footprint and unique properties, one of the promising materials for well cementing is geopolymers. Being a relatively new material, they are characterized by low carbon footprint, high acid resistance and attractive mechanical properties. This article is aimed at developing new geopolymer slurries for the oil industry, their characterization and field implementation analysis. With the ultimate goal of developing a methodology for the analysis of raw materials and designing the geopolymer slurries, studies were carried out on various raw materials, including different types of fly ash. Based on the data obtained and rapid screening methods, an approach was developed to formulate a geopolymer composition recipe. Since not all cement additives directly work in geopolymers, special attention was paid to control the thickening time and fluid loss. The methods of XRD, XRF, ICP-MS, density, particle size distribution measurements as well as API methods of cement testing were used to understand the composition and structure of the materials obtained, their properties and design limitations. A special approach was applied to study the acid resistance of the materials obtained and to compare with conventional cements and slags. Using one of the most common sources of aluminosilicate, fly ash, formulations with a density of 13.5 – 16.5 lbm/galUS were tested. A sensitivity analysis showed that the type of activator and its composition play a critical role both in the mechanical properties of the final product and in the solidification time and rheological properties of the product. The use of several samples of fly ash, significantly different in composition, made it possible to formulate the basic rules for the design of geopolymers for the oil industry. An analysis was also carried out on 10 different agents for filtration and 7 moderators to find a working formulation for the temperature range up to 100°C. The samples were systematically examined for changes in composition, strength, and acid resistance was previously measured. Despite the emergence of examples of the use of geopolymers in the construction industry and examples of laboratory testing of geopolymers for the oil industry, to the best of our knowledge, there has been no evidence of pumping geopolymers into a well. Our work is an attempt to develop an adaptation of the construction industry knowledge to the unique high pressure, high temperature conditions of the oil and gas industry. The ambitions of this work go far beyond the laboratory tests and involve yard test experiments.

scholarly journals Widespread QoI Fungicide Resistance Revealed Among Corynespora cassiicola Tomato Isolates in Florida

Plant Disease ◽  
2020 ◽  
Vol 104 (3) ◽  
pp. 893-903 ◽  
Author(s):  
Keevan J. MacKenzie ◽  
Katia V. Xavier ◽  
Aimin Wen ◽  
Sujan Timilsina ◽  
Heather M. Adkison ◽  
...  
Keyword(s):  
Amino Acid Position ◽  
Rapid Screening ◽  
Silent Mutation ◽  
Screening Methods ◽  
Corynespora Cassiicola ◽  
Qoi Fungicides ◽  
Quinone Outside Inhibitor ◽  
Target Spot ◽  
Moderately Resistant ◽  
Qoi Resistance

Target spot of tomato caused by Corynespora cassiicola is one of the most economically destructive diseases of tomato in Florida. A collection of 123 isolates from eight counties in Florida were evaluated for sensitivity to azoxystrobin and fenamidone based on mycelial growth inhibition (MGI), spore germination (SG), detached leaflet assays (DLAs), and sequence-based analysis of the cytochrome b gene (cytb). Cleavage of cytb by restriction enzyme (Fnu4HI) revealed the presence of a mutation conferring a glycine (G) to alanine (A) mutation at amino acid position 143 (G143A) in approximately 90% of the population, correlating with quinone outside inhibitor (QoI) resistance based on MGI (<40% at 5 μg/ml), SG (<50% at 1 and 10 μg/ml), and DLA (<10% severity reduction). The mutation conferring a phenylalanine (F) to leucine (L) substitution at position 129 (F129L) was confirmed in moderately resistant isolates (#9, #19, and #74) based on MGI (40 to 50% at 5 μg/ml), SG (<50% at 1 μg/ml and >50% at 10 μg/ml), and DLA (>10% and <43% severity reduction) for both QoI fungicides, whereas sensitive isolates (#1, #4, #7, #28, #29, #46, #61, #74, #75, #76, #91, #95, and #118) based on MGI (>50% at 5 μg/ml), SG (>50% at 1 μg/ml and 10 μg/ml), and DLA (>50% severity reduction) correlated to non-mutation-containing isolates or those with a silent mutation. This study indicates that QoI resistance among C. cassiicola isolates from tomato is widespread in Florida and validates rapid screening methods using MGI or molecular assays to identify resistant isolates in future studies.

scholarly journals Detection of Exon Deletions within an Entire Gene (CFTR) by Relative Quantification on the LightCycler

2006 ◽  
Vol 52 (11) ◽  
pp. 2005-2012 ◽  
Author(s):  
Mircea Schneider ◽  
Franziska Joncourt ◽  
Javier Sanz ◽  
Thomas von Känel ◽  
Sabina Gallati
Keyword(s):  
Gene Dosage ◽  
Large Deletion ◽  
Rapid Screening ◽  
Cftr Gene ◽  
Screening Methods ◽  
Sequence Variant ◽  
Β2 Microglobulin ◽  
Large Deletions ◽  
Specific Deletion ◽  
Entire Gene

Abstract Background: Cystic fibrosis (CF) is associated with at least 1 pathogen point sequence variant on each CFTR allele. Some symptomatic patients, however, have only 1 detectable pathogen sequence variant and carry, on the other allele, a large deletion that is not detected by conventional screening methods. Methods: For relative quantitative real-time PCR detection of large deletions in the CFTR gene, we designed DNA-specific primers for each exon of the gene and primers for a reference gene (β2-microglobulin). For PCR we used a LightCycler system (Roche) and calculated the gene-dosage ratio of CFTR to β2-microglobulin. We tested the method by screening all 27 exons in 3 healthy individuals and 2 patients with only 1 pathogen sequence variant. We then performed specific deletion screenings in 10 CF patients with known large deletions and a blinded analysis in which we screened 24 individuals for large deletions by testing 8 of 27 exons. Results: None of the ratios for control samples were false positive (for deletions or duplications); moreover, for all samples from patients with known large deletions, the calculated ratios for deleted exons were close to 0.5. In addition, the results from the blinded analysis demonstrated that our method can also be used for the screening of single individuals. Conclusions: The LightCycler assay allows reliable and rapid screening for large deletions in the CFTR gene and detects the copy number of all 27 exons.

Performance criteria for rapid screening methods to detect mycotoxins

2014 ◽  
Vol 7 (4) ◽  
pp. 439-447 ◽  
Author(s):  
C. von Holst ◽  
J. Stroka
Keyword(s):  
False Negative ◽  
Screening Method ◽  
Performance Criterion ◽  
Performance Criteria ◽  
Rapid Screening ◽  
Cost Ratio ◽  
Screening Methods ◽  
Method Performance ◽  
Official Control ◽  
The Impact

The paper describes the validation of screening methods that are used for official control to classify samples into negative and suspect positive samples. The concept is based on the principle that negative samples are considered as compliant, whereas suspect positive samples need to be re-analysed with confirmatory methods. An important performance criterion often used is a maximum value of 5% for the probability of false negative results obtained on samples that contain the analyte at the legal limit. Since the result of analysis is a binary decision, specific validation schemes need to be applied. The paper places emphasis on practical aspects of the calculation of the method performance characteristics, which are required to check whether the methods fulfil the performance criterion. The paper shows that screening methods based on a visual inspection, e.g. a dipstick, require special data treatment. In contrast there are many methods where the classification into negative and suspect positive samples is based on the comparison of a measured response against a cut-off value. This type of methods can be validated with quantitative statistics. The paper also elaborates on the calculation of the rate of false positive results of compliant samples. In addition the impact on the economical aspect of the use of the screening method is estimated, taking into account external factors such as the cost ratio between the screening and the confirmatory method and the occurrence of non-compliant samples in the entire population of the samples.

Rapid screening methods for beta-emitters in food samples

2015 ◽  
Vol 141 ◽  
pp. 130-137 ◽  
Author(s):  
A. Vos van Avezathe ◽  
P.N. Brandhoff ◽  
M.J. van Bourgondiën ◽  
G.C. Krijger
Keyword(s):  
Food Samples ◽  
Rapid Screening ◽  
Screening Methods ◽  
Beta Emitters

scholarly journals SLAMP: A Rapid Fluorometric RT-LAMP Assay for Sensitive and Specific Detection of SARS-CoV-2 from Human Saliva

2021 ◽  
Author(s):  
Dimitri Athan Bikos ◽  
Chiachi Hwang ◽  
Kristen A Brileya ◽  
Albert Parker ◽  
Emma Kate Loveday ◽  
...  
Keyword(s):  
Reverse Transcription ◽  
Quantitative Polymerase Chain Reaction ◽  
Lamp Assay ◽  
High Sensitivity ◽  
Human Saliva ◽  
The Body ◽  
Proteinase K ◽  
Rapid Screening ◽  
Screening Methods ◽  
Asymptomatic Individuals

Rapid testing methods can identify outbreaks and trigger preventive strategies for slowing the spread of SARS-CoV-2, the virus that causes COVID-19. The gold-standard detection method for SARS-CoV-2 is reverse transcription quantitative polymerase chain reaction (RT-qPCR) performed on samples collected using a nasopharyngeal (NP) swab. While NP RT-qPCR provides high sensitivity, it requires trained personnel to administer and suffers from lengthy time-to-result. Recently, the testing community has turned to rapid saliva-based screening methods including saliva-to-RT-qPCR and/or saliva-to-RT-LAMP (reverse transcription loop-mediated isothermal amplification) to identify infected individuals regardless of symptomatic presentation. Here, we report a simple and rapid RT-LAMP fluorometric assay performed directly on heat-inactivated saliva, without the addition of buffers or proteinase K treatments we call saliva LAMP (SLAMP). Over the course of two days, a total of 243 individuals were tested using NP RT-qPCR, saliva-based qPCR, and saliva-based RT-LAMP. Of the 243 NP RT-qPCR tests, 65 were positive, 178 were negative, and SLAMP demonstrated a 91% sensitivity and 98% specificity. SLAMP sensitivity becomes 95% when samples negative in saliva tests while positive in NP RT-qPCR are excluded from evaluation, potentially indicating significant differences in viral titer between collection sites on the body. SLAMP is performed in triplicates and takes 45 min to run in the laboratory, requiring less technician time and instrument run time than NP RT-qPCR. These results demonstrate that saliva-based RT-LAMP can enable frequent and rapid screening of large numbers of people to identify pre-symptomatic and asymptomatic individuals thereby controlling outbreaks.

scholarly journals Detection of Residues of Antimicrobial Compounds in Eggs by the Rapid Screening Methods

2018 ◽  
Vol 62 (3) ◽  
pp. 48-55
Author(s):  
M. Krišová ◽  
I. Kožárová
Keyword(s):  
Potable Water ◽  
Rapid Screening ◽  
Animal Origin ◽  
Effective Control ◽  
Human Consumption ◽  
Screening Methods ◽  
Antimicrobial Compounds ◽  
Disease Treatment ◽  
The Public ◽  
Antimicrobial Residues

Abstract Eggs belong to the most frequently consumed products of animal origin worldwide, and therefore the safety of eggs is a substantiated issue. Conventional poultry rearing involves the use of antimicrobials added to their feed or potable water particularly for disease treatment, however, in some countries also for the prevention of diseases, promotion of growth and better utilisation of the feed. Thus, effective control of residues of such substances in eggs is very important for the protection of the public health. The aim of this study was to detect the potential presence of antimicrobial residues in fresh hen eggs using commercially available rapid screening methods (Premi®Test and EXP Ampulle test) and compare the results of both of these tests. We examined 22 samples randomly selected from among 66 samples purchased in 11 European countries. We respected the procedures as supplied by the manufacturers of the tests together with their respective test kits. The examination of eggs by the Premi®Test did not detect the presence of antimicrobial residues in the samples, while the EXP Ampulle test provided 8 positive and 6 dubious results. Our results allowed us to conclude that the EXP Ampulle appears to be more sensitive and allows one to carry out more effective control of the presence of antimicrobial residues in hen eggs intended for human consumption.

scholarly journals Ochratoxin A Occurrence in Food

2010 ◽  
Vol 67 (2) ◽  
Author(s):  
Dana FEIER ◽  
Maria TOFANA
Keyword(s):  
Ochratoxin A ◽  
Large Scale ◽  
Poultry Meat ◽  
Screening Tests ◽  
Rapid Screening ◽  
Screening Methods ◽  
Ionization Mass ◽  
Promising Alternative ◽  
Analytical Technique ◽  
Analytical Approaches

The aim of the present study was to investigate the occurrence of Ochratoxin A (OA) in food based on the results of the investigation about the Assessment of dietary intake of Ochratoxin A by the population of EU Member States. Ochratoxin A (OTA) can occur in a large variety of commodities (cereals, beans, groundnuts, spices, dried fruits, coffee, beer, wine) and, because of a carry-over effect, in milk, pig blood, liver, and kidney, and poultry meat from animals fed with contaminated feed. Because of the persistence of OTA in the food chain, exposure to the compound is a potential human health hazard. This has prompted adoption of regulatory limits in several countries which, in turn, implies the development of suitable validated and official analytical methods and rapid screening tests for cost-effective food control on a large scale. Liquid chromatography with fluorescence detection (LC–FLD), coupled with immunoaffinity column (IAC) clean-up, is the most widely employed analytical technique. LC coupled with electrospray-ionization mass spectrometry (MS) has detection limits comparable with those of LC– FLD and the selectivity of IAC can be achieved by tandem (MS–MS) or sequential (MSn) detection. Synthetic counterparts to natural antibodies in the form of molecularly imprinted polymers seem a promising alternative to IAC for sample preparation. New analytical approaches to rapid, low-cost screening methods, for example those based on biosensors and dip-stick-like kits, are a direction in which innovation can be expected.

Sign in / Sign up

Export Citation Format

Share Document