scholarly journals A Controlled Study on the Characterisation of Bioaerosols Emissions from Compost

Atmosphere ◽  
2018 ◽  
Vol 9 (10) ◽  
pp. 379 ◽  
Author(s):  
Zaheer Nasir ◽  
Catherine Rolph ◽  
Samuel Collins ◽  
David Stevenson ◽  
Toni Gladding ◽  
...  
Keyword(s):  
Legionella Pneumophila ◽  
Detection System ◽  
Quantitative Polymerase Chain Reaction ◽  
Size Fraction ◽  
Data Interpretation ◽  
Controlled Study ◽  
Flight Mass Spectrometry ◽  
High Emission ◽  
Spectral Profiles ◽  
Bioaerosol Detection

Bioaerosol emissions arising from biowaste treatment are an issue of public concern. To better characterise the bioaerosols, and to assess a range of measurement methods, we aerosolised green waste compost under controlled conditions. Viable and non-viable Andersen samplers, cyclone samplers and a real time bioaerosol detection system (Spectral Intensity Bioaerosol Sensor (SIBS)) were deployed simultaneously. The number-weighted fraction of fluorescent particles was in the range 22–26% of all particles for low and high emission scenarios. Overall fluorescence spectral profiles seen by the SIBS exhibited several peaks across the 16 wavelength bands from 298 to 735 nm. The size-fractionated endotoxin profile showed most endotoxin resided in the 2.1–9 μm aerodynamic diameter fraction, though up to 27% was found in a finer size fraction. A range of microorganisms were detected through culture, Matrix Assisted Laser Desorption and Ionisation Time of Flight Mass Spectrometry (MALDI-TOF) and quantitative polymerase chain reaction (qPCR), including Legionella pneumophila serogroup 1. These findings contribute to our knowledge of the physico-chemical and biological characteristics of bioaerosols from composting sites, as well as informing future monitoring approaches and data interpretation for bioaerosol measurement.

scholarly journals Validation and in-field testing of a new on-site qPCR system for quantification of Legionella pneumophila according to ISO/TS 12869:2012 in HVAC cooling towers

2019 ◽  
Vol 17 (2) ◽  
pp. 237-253 ◽  
Author(s):  
Shaimaa Ahmed ◽  
Urszula Liwak-Muir ◽  
Danielle Walker ◽  
Agnes Zoldowski ◽  
Alan Mears ◽  
...  
Keyword(s):  
Legionella Pneumophila ◽  
Limit Of Detection ◽  
Detection System ◽  
Quantitative Polymerase Chain Reaction ◽  
Technical Specification ◽  
Turnaround Time ◽  
Laboratory Culture ◽  
International Standards ◽  
Cooling Towers ◽  
Sample Collection

Abstract Legionella pneumophila, found in engineered water systems such as HVAC cooling towers, poses a significant public health risk. Culture, though routinely used to quantify L. pneumophila, has several disadvantages including long turnaround time, low sensitivity, and inter-laboratory variability. In this study, we validated the performance of an on-site quantitative polymerase chain reaction (qPCR) detection system for L. pneumophila in accordance with International Standards Organization Technical Specification 12869:2012. We evaluated specificity, limit of detection and quantification, and calibration curve linearity. Additionally, we evaluated whole system recovery and robustness using samples taken from taps and evaporative cooling towers. We then compared the system's performance against laboratory culture and laboratory qPCR across 53 cooling towers in a 12-week in-field study. We found that concordance between on-site qPCR and culture was both laboratory- and site/sample-dependent. Comparison of laboratory qPCR with on-site qPCR revealed that laboratory results were highly variable and showed little concordance. Some discordance may be explained by time delay between sample collection and testing (‘shipping effect’) which may lead to inaccurate reporting. Overall, our study highlights the value of on-site qPCR detection of L. pneumophila, demonstrates that laboratories are prone to misreporting results due to shipping effects, and reveals significant discordance between laboratory qPCR and culture.

scholarly journals A New Molecular Detection System for Canine Distemper Virus Based on a Double-Check Strategy

Viruses ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1632
Author(s):  
Sabrina Halecker ◽  
Sabine Bock ◽  
Martin Beer ◽  
Bernd Hoffmann
Keyword(s):  
Canine Distemper Virus ◽  
Parallel Implementation ◽  
Detection System ◽  
Quantitative Polymerase Chain Reaction ◽  
Diagnostic Methods ◽  
Molecular Diagnostic ◽  
Wild Animals ◽  
Canine Distemper ◽  
One Step ◽  
Diagnostic Sensitivity And Specificity

Due to changing distemper issues worldwide and to inadequate results of an inter-laboratory study in Germany, it seems sensible to adapt and optimize the diagnostic methods for the detection of the canine distemper virus (CDV) to the new genetic diversity of virus strains. The goal of the project was the development, establishment and validation of two independent one-step reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) methods for the safe detection of CDV in domestic and wild animals. For this purpose, an existing CDV-RT-qPCR was decisively adapted and, in addition, a completely new system was developed. Both CDV-RT-qPCR systems are characterized by a very high, comparable analytical and diagnostic sensitivity and specificity and can be mutually combined with inhibition or extraction controls. The reduction in the master mix used allows for the parallel implementation of both CDV-RT-qPCR systems without significant cost increases. For validation of the new CDV-RT-qPCR duplex assays, a panel comprising 378 samples derived from Germany, several European countries and one African country were tested. A sensitivity of 98.9% and a specificity of 100% were computed for the new assays, thus being a reliable molecular diagnostic tool for the detection of CDV in domestic and wild animals.

High-Speed Real-Time Ion Detection System for Time-of-Flight Mass Spectrometry Application

2012 ◽  
Vol 45 (6) ◽  
pp. 464-469 ◽  
Author(s):  
Nan Li ◽  
Hui Xu ◽  
Qingjiang Li ◽  
Yinan Wang ◽  
Jinling Xing ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Real Time ◽  
High Speed ◽  
Detection System ◽  
Time Of Flight ◽  
Ion Detection ◽  
Flight Mass Spectrometry ◽  
Mass Spectrometry Application

scholarly journals Quantitative Real-Time Legionella PCR for Environmental Water Samples: Data Interpretation

2006 ◽  
Vol 72 (4) ◽  
pp. 2801-2808 ◽  
Author(s):  
Philippe Joly ◽  
Pierre-Alain Falconnet ◽  
Janine André ◽  
Nicole Weill ◽  
Monique Reyrolle ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Legionella Pneumophila ◽  
Cooling Tower ◽  
Water System ◽  
Data Interpretation ◽  
Environmental Water ◽  
Hot Water ◽  
Rrna Gene ◽  
Conventional Culture

ABSTRACT Quantitative Legionella PCRs targeting the 16S rRNA gene (specific for the genus Legionella) and the mip gene (specific for the species Legionella pneumophila) were applied to a total of 223 hot water system samples (131 in one laboratory and 92 in another laboratory) and 37 cooling tower samples (all in the same laboratory). The PCR results were compared with those of conventional culture. 16S rRNA gene PCR results were nonquantifiable for 2.8% of cooling tower samples and up to 39.1% of hot water system samples, and this was highly predictive of Legionella CFU counts below 250/liter. PCR cutoff values for identifying hot water system samples containing >103 CFU/liter legionellae were determined separately in each laboratory. The cutoffs differed widely between the laboratories and had sensitivities from 87.7 to 92.9% and specificities from 77.3 to 96.5%. The best specificity was obtained with mip PCR. PCR cutoffs could not be determined for cooling tower samples, as the results were highly variable and often high for culture-negative samples. Thus, quantitative Legionella PCR appears to be applicable to samples from hot water systems, but the positivity cutoff has to be determined in each laboratory.

Constant-Fraction Discrimination/Boxcar Integrator for Plasma Source Time-of-Flight Mass Spectrometry

1995 ◽  
Vol 49 (5) ◽  
pp. 660-664 ◽  
Author(s):  
Pengyuan Yang ◽  
David P. Myers ◽  
Gangqiang Li ◽  
Gary M. Hieftje
Keyword(s):  
Mass Spectrometry ◽  
Inductively Coupled Plasma ◽  
Dynamic Range ◽  
Detection System ◽  
Signal To Noise Ratio ◽  
Time Of Flight ◽  
Plasma Source ◽  
Flight Mass Spectrometry ◽  
Lower Amplitude ◽  
Boxcar Integrator

A constant-fraction discrimination (CFD) system has been combined with a boxcar integrator for detection in inductively coupled plasma/time-of-flight mass spectrometry. The discriminator provides gating logic for the boxcar integrator when an incoming ion signal occurs, but discriminates against electronic or background noise of lower amplitude. As a result, the combination can effectively reject noise and accumulate analyte signal, rather than relying on an averaging process to reduce noise levels. The signal-to-noise ratio is therefore enhanced in this operation compared with the conventional boxcar method. The dynamic range of the detection system is at least five orders of magnitude.

scholarly journals Honey Bee(Apis mellifera)Exposomes and Biological Pathways Associated withNosema ceranaeInfection

2017 ◽  
Author(s):  
Robert L. Broadrup ◽  
Christopher Mayack ◽  
Sassicaia J. Schick ◽  
Elizabeth J. Eppley ◽  
Helen K. White ◽  
...  
Keyword(s):  
Apis Mellifera ◽  
Biological Effects ◽  
Quantitative Polymerase Chain Reaction ◽  
Biological Pathways ◽  
Nosema Ceranae ◽  
Flight Mass Spectrometry ◽  
Bee Health ◽  
Polymerase Chain ◽  
And Control

AbstractA pilot study was conducted to determine if exposome profiles of honey bees(Apis mellifera)are associated withNosema ceranaeinfection and whether xenobiotic exposures effect changes in known biological pathways of bees. Thirty stationary hives were selected from seven apiaries representing urban and suburban geographies. Foraging bees were harvested during the summer of 2015 and analyzed forNosema ceranaeinfection via semi-quantitative polymerase chain reaction (sq-PCR) and discovery-based exposome analysis via gas chromatography-time of flight mass spectrometry (GC-TOF). The resulting datasets were divided into case and control groups based on the prevalence ofN. ceranaeinfection. Xenobiotic burden was determined to be associated withN. ceranaeinfection, and co-variate analysis determined differentially expressed biological chemicals and naturally occurring chemicals in the bee exposomes. Biological pathways analyses putatively identified 10 dysregulated pathways as well as the presence of the P450 oxidative metabolism of naphthalene for detoxification. Based on these results, it is evident that the integration of genetic disease screening with discovery-based exposomics provides a promising multi-omic platform to identify adverse biological effects to bees occurring from exposures to chemicals and parasites. In addition, this approach will generate new hypotheses for targeted follow-up studies to examine bee health.

scholarly journals The association between RANK, RANKL and OPG gene polymorphisms and the risk of rheumatoid arthritis: a case-controlled study and meta-analysis

2019 ◽  
Vol 39 (6) ◽  
Author(s):  
Haoyu Yang ◽  
Weixi Liu ◽  
Xindie Zhou ◽  
Huan Rui ◽  
Hui Zhang ◽  
...  
Keyword(s):  
Rheumatoid Arthritis ◽  
Gene Polymorphisms ◽  
Meta Analysis ◽  
Nuclear Factor Κb ◽  
Controlled Study ◽  
Female Age ◽  
Flight Mass Spectrometry ◽  
Base Extension ◽  
Different Populations ◽  
Rank Gene

Abstract The receptor activator of nuclear factor-κB (RANK) and the osteoprotegerin (OPG) cascade system have been reported to be essential in osteoclastogenesis. In recent years, several studies have investigated the association between polymorphisms of RANK, its ligand RANKL and OPG genes and the risk of rheumatoid arthritis (RA) in different populations. However, the results arising from these studies were conflicting. To determine the association between RANK, RANKL and OPG gene polymorphisms and the risk of RA. We conducted a hospital-based case-controlled study in Changzhou with 574 RA cases and 804 controls. The genotyping of RANK gene rs1805034 polymorphism was conducted by single base extension combined with matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS). We also undertook a meta-analysis of the literature referring to polymorphisms of RANK, RANKL and OPG genes and RA risk. This case-controlled study found that the polymorphism in the RANK gene rs1805034 was not related to RA risk. Stratification analyses by sex and age suggested that RANK gene rs1805034 polymorphism was not associated with the risk of RA among groups of male, female, age ≤ 55 and age > 55. Our meta-analysis found that the rs2277438 polymorphism in RANKL gene increased the risk of RA, whereas RANK gene rs1805034, OPG gene rs3102735, OPG gene rs2073618, OPG gene rs3134069 polymorphisms were not related to RA susceptibility. In conclusion, this case-controlled study and meta-analysis indicated that the RANKL gene rs2277438 polymorphism increased the RA risk, and that RANK gene rs1805034, OPG gene rs3102735, OPG gene rs2073618, OPG gene rs3134069 polymorphisms were not related to RA risk.

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