Factors influencing recovery of SARS-CoV-2 RNA in raw sewage and wastewater sludge using polyethylene glycol–based concentration method

AbstractMacroprolactinaemia is a major cause of hyperprolactinaemia. The detectability of macroprolactin varies widely among different immunoassay systems, but the causes are not fully known. This study aimed to identify the factors influencing the detectability of macroprolactin by immunoassay systems.The study included 1544 patients who visited an obstetric and gynaecological hospital. Macroprolactinaemia was screened using the polyethylene glycol (PEG) method and confirmed using gel filtration chromatography and the protein G method. The prolactin (PRL) values determined by enzyme immunoassay (EIA) were compared with those of a chemiluminescence immunoassay system (Centaur) that is known to cross-react the least with macroprolactin.Macroprolactinaemia was found in 62 of 1544 patients (4.02%) who visited an obstetric and gynaecological hospital. The ratio of EIA-determined total PRL to free PRL in the supernatant after PEG precipitation was significantly elevated in all 62 serum samples with macroprolactin compared to those in 1482 serum samples without macroprolactin. In contrast, the ratio of Centaur-determined total PRL to free PRL was significantly elevated in 32 serum samples (group 1) and was within the normal range in 30 (group 2) of 62 serum samples with macroprolactin. The prevalence of non-IgG-type macroprolactin was significantly higher in group 1 than in group 2. Centaur diagnosed hyperprolactinaemia less frequently than EIA (n=2 vs. 16) in 62 patients with macroprolactinaemia. Those two hyperprolactinaemic patients diagnosed by Centaur had non-IgG-type macroprolactin.Macroprolactinaemia was present in 4% of patients visiting an obstetric and gynaecological hospital. The nature of macroprolactin (IgG-type or non-IgG-type) may partly explain why macroprolactin detectability varies among different immunoassay systems.

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2L of Polyethylene Glycol as the Main Small Bowel Cleansing Regimen Component Prior to Video Capsule Endoscopy: Interim Analysis

Proceedings of the Latvian Academy of Sciences. Section B. Natural, Exact, and Applied Sciences. ◽

10.2478/prolas-2020-0013 ◽

2020 ◽

Vol 74 (2) ◽

pp. 83-87

Author(s):

Aleksejs Derovs ◽

Jeļena Derova ◽

Regīna Kleina ◽

Juris Pokrotnieks

Keyword(s):

Polyethylene Glycol ◽

Small Bowel ◽

Transit Time ◽

Capsule Endoscopy ◽

Interim Analysis ◽

Preparation Methods ◽

Diagnostic Endoscopy ◽

Factors Influencing ◽

Bowel Cleansing

AbstractCapsule Enteroscopy (CE) is a fundamentally new method in diagnostic endoscopy. However, there are several factors influencing the quality of this procedure, including impermeable fluids, food remains etc. The aim of the study was to assess one of the most popular currently used bowel preparation methods and evaluate possible effects of various factors. 136 CE examinations were analysed. Each patient was prepared using 2 litres of polyethylene glycol (PEG) one day prior to examination. There was a special form filled in for each patient, which included relevant parameters (anamnesis, CE data etc.). Of 136 CE cases, 84 (61.8%) were female patients and 52 (38.2%) were male. The small bowel (SB) transit time in 112 patients varied from 39 to 502 minutes, but in 24 cases the capsule did not reach caecum. The degree of bowel cleanliness was as follows: very good — 30 (22.1%) patients, satisfactory — 97 (71.3%), and poor — 9 (6.6%). A positive correlation was observed between the degree of SB cleanliness and the SB transit time (p = 0.015). A longer SB transits time was associated with poor SB cleanliness. The results obtained in this study showed that the quality of SB cleanliness is affected by SB transit time. A relatively large percentage of cases rated as satisfactory bowel cleanliness and comparatively small percentage of bowel cleanliness cases rated as “very good” were observed when 2 litres of PEG were used prior to CE, indicating an important issues in preparation of the bowel prior to CE.

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Concentration and Quantification of SARS-CoV-2 RNA in Wastewater Using Polyethylene Glycol-Based Concentration and qRT-PCR

Methods and Protocols ◽

10.3390/mps4010017 ◽

2021 ◽

Vol 4 (1) ◽

pp. 17

Author(s):

Kata Farkas ◽

Luke S. Hillary ◽

Jamie Thorpe ◽

David I. Walker ◽

James A. Lowther ◽

...

Keyword(s):

Polyethylene Glycol ◽

Simple Procedure ◽

Rna Extraction ◽

Chemical Properties ◽

Qrt Pcr ◽

Reverse Transcription Pcr ◽

Concentration Method ◽

Physico Chemical ◽

One Step ◽

Wastewater Samples

Wastewater-based epidemiology has become an important tool for the surveillance of SARS-CoV-2 outbreaks. However, the detection of viruses in sewage is challenging and to date there is no standard method available which has been validated for the sensitive detection of SARS-CoV-2. In this paper, we describe a simple concentration method based on polyethylene glycol (PEG) precipitation, followed by RNA extraction and a one-step quantitative reverse transcription PCR (qRT-PCR) for viral detection in wastewater. PEG-based concentration of viruses is a simple procedure which is not limited by the availability of expensive equipment and has reduced risk of disruption to consumable supply chains. The concentration and RNA extraction steps enable 900–1500× concentration of wastewater samples and sufficiently eliminates the majority of organic matter, which could inhibit the subsequent qRT-PCR assay. Due to the high variation in the physico-chemical properties of wastewater samples, we recommend the use of process control viruses to determine the efficiency of each step. This procedure enables the concentration and the extraction the DNA/RNA of different viruses and hence can be used for the surveillance of different viral targets for the comprehensive assessment of viral diseases in a community.

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Detection of SARS-CoV-2 in wastewater is influenced by sampling time, concentration method, and target analyzed

Journal of Water and Health ◽

10.2166/wh.2021.133 ◽

2021 ◽

Author(s):

Nancy J. Pino ◽

Diana C. Rodriguez ◽

Laura Castrillón Cano ◽

Alejandra Rodriguez

Keyword(s):

Polyethylene Glycol ◽

Skim Milk ◽

Sampling Time ◽

Deionized Water ◽

Important Data ◽

Infected People ◽

Concentration Method ◽

Polyethylene Glycol Precipitation ◽

Storage Times ◽

Concentration Methods

Abstract The detection of SARS-CoV in wastewater has been proposed as a tool for monitoring COVID-19 at the community level. Although many reports have been published about detecting viral RNA in wastewater and its presence has been linked to infected people, appropriate analytical methodologies to use this approach have not yet been established. In this study, we compared ultrafiltration, polyethylene glycol precipitation, flocculation using AlCl3, and flocculation with skim milk for the recovery of SARS-CoV-2, using RNA from patients with positive diagnoses for COVID-19 and Pseudomonas phage φ6 as the control. We also evaluated the primers for detecting the E, RdRp, and N genes of the virus, as well as different storage times. Differences in the recovery efficiencies were evident with the different concentration methods, the best being ultrafiltration and precipitation with aluminum, which had recovery rates of 42.0% and 30.0%, respectively, when virus was present at high levels. Significant differences were found between the recoveries using wastewater and deionized water and between different storage times, with better recoveries for 6 and 12 h samplings. The E gene was the only one detected in all the samples analyzed. The results show that although this approach can provide important data for studying the pandemic, clear protocols are necessary for investigations to be comparable. HIGHTLIGHTS RNA of SARS-CoV-2 was used to evaluate the recovery of different methods in wastewater. The utility of phage φ6 of Pseudomonas as a control for evaluation of recovery methods of SARS-CoV-2 from wastewater was demonstrated. Differences due to the target selected for the detection of SARS was demonstrated. The results show that it is possible to detect SARS RNA in wastewater, however its epidemiological usefulness will depend on the correct validation of the technique used for detection.

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Factors influencing the binding of a potassium cation to a polyethylene glycol type podand in liquid–liquid extraction—a molecular dynamics study

Theoretical Chemistry Accounts ◽

10.1007/s00214-010-0778-7 ◽

2010 ◽

Vol 127 (5-6) ◽

pp. 681-687 ◽

Cited By ~ 4

Author(s):

Mário Valente ◽

Sérgio Filipe Sousa ◽

A. L. Magalhães ◽

Cristina Freire

Keyword(s):

Molecular Dynamics ◽

Polyethylene Glycol ◽

Liquid Extraction ◽

Potassium Cation ◽

Liquid Liquid Extraction ◽

Factors Influencing

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Some factors influencing production of transgenic plants in polyethylene glycol-mediated transformation of rice protoplasts

Rice Genetics Collection - Rice Genetics II ◽

10.1142/9789812814289_0087 ◽

2008 ◽

pp. 703-709

Author(s):

H. Chaïr ◽

T. Legavre ◽

E. Guiderdoni

Keyword(s):

Polyethylene Glycol ◽

Transgenic Plants ◽

Factors Influencing

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Factors influencing adhesive bonding at the bone/implant interface

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100130201 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1114-1115

Author(s):

Julie A. Martini ◽

Robert H. Doremus

Keyword(s):

Electron Microscopy ◽

Adhesive Bonding ◽

Microscopy Study ◽

Electron Microscopy Study ◽

Bone Implant ◽

Factors Influencing ◽

Lr White ◽

Transmission Electron ◽

New Zealand White Rabbits ◽

Scanning Electron

Tracy and Doremus have demonstrated chemical bonding between bone and hydroxylapatite with transmission electron microscopy. Now researchers ponder how to improve upon this bond in turn improving the life expectancy and biocompatibility of implantable orthopedic devices.This report focuses on a study of the- chemical influences on the interfacial integrity and strength. Pure hydroxylapatite (HAP), magnesium doped HAP, strontium doped HAP, bioglass and medical grade titanium cylinders were implanted into the tibial cortices of New Zealand white rabbits. After 12 weeks, the implants were retrieved for a scanning electron microscopy study coupled with energy dispersive spectroscopy.Following sacrifice and careful retrieval, the samples were dehydrated through a graduated series starting with 50% ethanol and continuing through 60, 70, 80, 90, 95, and 100% ethanol over a period of two days. The samples were embedded in LR White. Again a graduated series was used with solutions of 50, 75 and 100% LR White diluted in ethanol.

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Immunocytochemical detection of hepatic carbohydrate metabolic enzymes: Improved resolution with polyethylene glycol embedding and visio-bond semithin sections

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100124367 ◽

1992 ◽

Vol 50 (1) ◽

pp. 792-793

Author(s):

Kuixiong Gao ◽

Randal E. Morris ◽

Bruce F. Giffin ◽

Robert R. Cardell

Keyword(s):

Polyethylene Glycol ◽

Glycogen Phosphorylase ◽

Phosphoenolpyruvate Carboxykinase ◽

Glycogen Synthase ◽

Metabolic Enzymes ◽

Silver Stain ◽

Accurate Localization ◽

Immunocytochemical Detection ◽

Semithin Sections ◽

Parenchymal Cells

Several enzymes are involved in the regulation of anabolic and catabolic pathways of carbohydrate metabolism in liver parenchymal cells. The lobular distribution of glycogen synthase (GS), phosphoenolpyruvate carboxykinase (PEPCK) and glycogen phosphorylase (GP) was studied by immunocytochemistry using cryosections of normal fed and fasted rat liver. Since sections of tissue embedded in polyethylene glycol (PEG) show good morphological preservation and increased detectability for immunocytochemical localization of antigenic sites, and semithin sections of Visio-Bond (VB) embedded tissue provide higher resolution of cellular structure, we applied these techniques and immunogold-silver stain (IGSS) for a more accurate localization of hepatic carbohydrate metabolic enzymes.

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