scholarly journals Survival of Human Norovirus Surrogates in Water upon Exposure to Thermal and Non-Thermal Antiviral Treatments

Viruses ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 461
Author(s):  
Shu Zhu ◽  
Candace Barnes ◽  
Sutonuka Bhar ◽  
Papa Hoyeck ◽  
Annalise N. Galbraith ◽  
...  
Keyword(s):  
Disease Outbreaks ◽  
Environmental Water ◽  
Murine Norovirus ◽  
Chemical Additives ◽  
Human Norovirus ◽  
Chitosan Microparticles ◽  
The Stability ◽  
A Minor ◽  
Physical And Chemical ◽  
The Impact

Human noroviruses are the leading cause of foodborne gastroenteritis worldwide and disease outbreaks have been linked to contaminated surface waters as well as to produce consumption. Noroviruses are extremely stable in water and their presence is being detected with increasing frequency, yet there are no viable methods for reducing norovirus contamination in environmental water. Despite this, there is little knowledge regarding the physical and chemical factors that influence the environmental persistence of this pathogen. This study evaluated the impact of common chemical and physical properties of surface water on the stability of murine norovirus and examined the effect of food-safe chitosan microparticles on infectivity of two human norovirus surrogates. While chemical additives had a minor impact on virus survival, chitosan microparticles significantly reduced infectious titers of both murine norovirus and MS2 bacteriophage.

Application of chitosan microparticles against human norovirus

2021 ◽  
Author(s):  
Candace Barnes ◽  
Rebecca Barber ◽  
Keith R. Schneider ◽  
Michelle D. Danyluk ◽  
Anita C. Wright ◽  
...  
Keyword(s):  
Environmental Water ◽  
The United States ◽  
Virus Infectivity ◽  
Log10 Reduction ◽  
Human Norovirus ◽  
Virus Particles ◽  
Chitosan Microparticles ◽  
Natural Treatment ◽  
Fecal Suspension ◽  
Tulane Virus

Human norovirus (HuNoV) is the leading causative agent of foodborne outbreaks and is associated with the second most prevalent cause of waterborne infections in the United States. The goal of this research was to investigate the antiviral activity of chitosan microparticles (CM) against HuNoV GII.4 Sydney and its cultivable surrogate, Tulane virus (TuV), in suspensions mimicking fecally-contaminated water. CM was prepared by crosslinking chitosan molecules with sodium sulfate, and then its anti-noroviral activity was assessed using infectivity assay on TuV and RT-qPCR on TuV and HuNoV. A 3% CM suspension in PBS (pH 7.2) showed binding to TuV particles but with a negligible impact on virus infectivity (p>0.05). TuV and HuNoV suspended in fecal suspensions showed a 1.5-log10 reduction in genomic copies per ml following a 10-min contact time (p<0.05). Despite the negligible impact on viral infectivity, CM moderately binds to virus particles and helps purify environmental water by removing infectious virus particles. In this study, TuV served as a suitable surrogate for HuNoV by showing a similar log10 reduction in fecal suspension. Overall, the outcomes of thisresearch highlight the potential application of CM as a novel, natural treatment to minimize the spread of water-transmitted viral pathogens.

scholarly journals Attach Me If You Can: Murine Norovirus Binds to Commensal Bacteria and Fungi

Viruses ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 759 ◽  
Author(s):  
Jasmine L. Madrigal ◽  
Sutonuka Bhar ◽  
Samantha Hackett ◽  
Haley Engelken ◽  
Ross Joseph ◽  
...  
Keyword(s):  
Incubation Temperature ◽  
Growth Conditions ◽  
Fungal Species ◽  
Commensal Bacteria ◽  
Murine Norovirus ◽  
Human Norovirus ◽  
Viral Pathogens ◽  
Bacteria And Fungi ◽  
The Impact ◽  
Murine Noroviruses

The presence of commensal bacteria enhances both acute and persistent infection of murine noroviruses. For several enteric viral pathogens, mechanisms by which these bacteria enhance infection involve direct interactions between the virus and bacteria. While it has been demonstrated that human noroviruses bind to a variety of commensal bacteria, it is not known if this is also true for murine noroviruses. The goal of this study was to characterize interactions between murine noroviruses and commensal bacteria and determine the impact of bacterial growth conditions, incubation temperature and time, on murine norovirus attachment to microbes that comprise the mammalian microbiome. We show that murine noroviruses bind directly to commensal bacteria and show similar patterns of attachment as human norovirus VLPs examined under the same conditions. Furthermore, while binding levels are not impacted by the growth phase of the bacteria, they do change with time and incubation temperature. We also found that murine norovirus can bind to a commensal fungal species, Candida albicans.

Small-bioreactor platform technology as a municipal wastewater additive treatment

2013 ◽  
Vol 69 (3) ◽  
pp. 504-510 ◽  
Author(s):  
Ofir Menashe ◽  
Eyal Kurzbaum
Keyword(s):  
Biological Treatment ◽  
Municipal Wastewater ◽  
Selection Process ◽  
Study Results ◽  
Different Types ◽  
Selective Forces ◽  
The Stability ◽  
Physical And Chemical ◽  
The Impact ◽  
The Relationship

The bioaugmentation treatment approach presents both an economical and environmentally friendly solution for wastewater treatment. However, the use of exogenous bacterial cultures presents several limitations: negative interaction between microorganisms and adaptation to new physical and chemical composite environment. These selective forces create a significant challenge for the introduced culture to achieving the required biomass in order to conduct the target biological treatment. Small-bioreactor platform (SBP) technology is aimed at introducing exogenous bacterial culture with some protection to reduce some of the natural selection process. The current study was aimed at validating the use of SBP technology to improve biological treatment, especially during a stress period, by using macro-encapsulated bioaugmentation treatment. The study results indicate that the use of SBP technology elevates the stability of biological treatment, improving operational factors such as the reduction of foaming phenomena and sludge accumulation. Still, a significant study needs to be conducted to understand the potential of this technology; especially the impact on biological treatment by using different types of microorganisms for different types of wastewaters and the relationship between the biomass within the SBP capsules and the natural microorganisms.

Hand Hygiene Regimens for the Reduction of Risk in Food Service Environments

2012 ◽  
Vol 75 (7) ◽  
pp. 1303-1309 ◽  
Author(s):  
SARAH L. EDMONDS ◽  
ROBERT R. McCORMACK ◽  
SIFANG STEVE ZHOU ◽  
DAVID R. MACINGA ◽  
CHRISTOPHER M. FRICKER
Keyword(s):  
Hand Hygiene ◽  
Food Service ◽  
Hand Washing ◽  
Soil Conditions ◽  
Murine Norovirus ◽  
Human Norovirus ◽  
E Coli ◽  
Log Reduction ◽  
Product Formulation ◽  
The Impact

Pathogenic strains of Escherichia coli and human norovirus are the main etiologic agents of foodborne illness resulting from inadequate hand hygiene practices by food service workers. This study was conducted to evaluate the antibacterial and antiviral efficacy of various hand hygiene product regimens under different soil conditions representative of those in food service settings and assess the impact of product formulation on this efficacy. On hands contaminated with chicken broth containing E. coli, representing a moderate soil load, a regimen combining an antimicrobial hand washing product with a 70% ethanol advanced formula (EtOH AF) gel achieved a 5.22-log reduction, whereas a nonantimicrobial hand washing product alone achieved a 3.10-log reduction. When hands were heavily soiled from handling ground beef containing E. coli, a wash-sanitize regimen with a 0.5% chloroxylenol antimicrobial hand washing product and the 70% EtOH AF gel achieved a 4.60-log reduction, whereas a wash-sanitize regimen with a 62% EtOH foam achieved a 4.11-log reduction. Sanitizing with the 70% EtOH AF gel alone was more effective than hand washing with a nonantimicrobial product for reducing murine norovirus (MNV), a surrogate for human norovirus, with 2.60- and 1.79-log reductions, respectively. When combined with hand washing, the 70% EtOH AF gel produced a 3.19-log reduction against MNV. A regimen using the SaniTwice protocol with the 70% EtOH AF gel produced a 4.04-log reduction against MNV. These data suggest that although the process of hand washing helped to remove pathogens from the hands, use of a wash-sanitize regimen was even more effective for reducing organisms. Use of a high-efficacy sanitizer as part of a wash-sanitize regimen further increased the efficacy of the regimen. The use of a well-formulated alcohol-based hand rub as part of a wash-sanitize regimen should be considered as a means to reduce risk of infection transmission in food service facilities.

scholarly journals Enhanced Viscosity of Aqueous Palygorskite Suspensions through Physical and Chemical Processing

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Feng-shan Zhou ◽  
Tian-qi Li ◽  
Yun-hua Yan ◽  
Can Cao ◽  
Lin Zhou ◽  
...  
Keyword(s):  
Magnesium Oxide ◽  
Apparent Viscosity ◽  
Chemical Processing ◽  
Chemical Additives ◽  
Structural Inversion ◽  
Oxide Particles ◽  
Ultrasound Scattering ◽  
Viscosity Enhancement ◽  
The Stability ◽  
Physical And Chemical

Palygorskite has remarkable rheological properties and was used to increase the stability and viscosity of aqueous suspensions. The effects of different physical and chemical processing methods on the apparent viscosity and plastic viscosity of the palygorskite suspensions such as pressing, ultrasound scattering, acidification, and chemical additives have been released. The pressing and ultrasound scattering indicated that the dispersed state of palygorskite could be increased effectively after treatment, and the apparent viscosity of treated-palygorskite samples increased almost 2-3 times compared to that of before. The viscosity of the acid-treated palygorskite suspension was not increased. The viscosity increased with the content of bentonite in the mixture of bentonite and palygorskite in fresh water. It seemed to be not worthy to add a certain amount of bentonite to palygorskite in order to enhance viscosity and vice versa. Chemical additives appeared to have good effects on the rheological behavior of palygorskite suspension. Magnesium oxide revealed great contribution to viscosity enhancement. The main mechanism was the electrostatic attractive interaction between magnesium oxide particles with positive charges and the palygorskite rods with negative charges. This interacted force has an impact on the structural inversion of palygorskite rods and even caused the reinforcing of flocculation.

scholarly journals The impact of storage conditions on the stability of sugarcane powder biofortified with kefir grains

2015 ◽  
Vol 68 (2) ◽  
pp. 7703-7712 ◽  
Author(s):  
Blanca Cecilia Salazar Alzate ◽  
Misael Cortés Rodríguez ◽  
Olga Inés Montoya Campuzano
Keyword(s):  
Functional Food ◽  
Physiological Activity ◽  
Survival Rates ◽  
Chemical Properties ◽  
Storage Conditions ◽  
High Viability ◽  
Kefir Grains ◽  
The Stability ◽  
Physical And Chemical ◽  
The Impact

The goal of this research project was to assess the quality of sugarcane powder, during storage, that had been biofortified with kefir grains (SP+KG). The powder was obtained by spray drying (SD) sugarcane concentrate that was previously fermented with kefir grains (KG). Maltodextrin, 20% w/w, was used as a drying additive, and high viability of the microbial consortium (lactobacilli, lactococci and yeast) was always sought in order to obtain a functional food enriched with probiotic microorganisms, which facilitate storage and consumption. The product was packed, both vacuum (V) and non-vacuum (WV), and stored at 10, 20 and 30°C for 180 days. The results showed significant differences (p < 0.05) in the survival rate of lactobacilli and lactococci for the time, temperature and packaging type (PT) factors; however, the yeast showed no significant differences for the PT factor. For the survival of yeast, lactococci and lactobacilli, the best temperature was 10°C and the best packaging type was V. The survival rates reached with these conditions were 62.82% (yeast), 81.22% (lactococci) and 87.82% (lactobacilli). In addition, the levels attained in terms of physical and chemical properties defined the quality specifications of the product. The sugarcane matrix is an effective vehicle of components with physiological activity such as the microorganisms present in kefir. This qualifies the product as a potential functional food.

The Stability of Regional Input—Output Multipliers

1977 ◽  
Vol 9 (2) ◽  
pp. 197-214 ◽  
Author(s):  
R S Conway
Keyword(s):  
Impact Analysis ◽  
Temporal Stability ◽  
Washington State ◽  
Input Output ◽  
Minor Problem ◽  
The Stability ◽  
A Minor ◽  
The Impact ◽  
Forecasting Errors ◽  
Over Time

Changes in regional input—output structures are studied by analyzing the temporal stability of income and output multipliers derived from the Washington State input—output tables for 1963, 1967, and 1972. One conclusion is that for impact analysis, as it is most commonly practiced, the instability of multipliers over time appears to be a minor problem. This judgment is based upon a comparison of forecasting errors in impact studies due to temporal changes in multipliers with forecasting errors arising from other aspects of the impact estimating procedure. The implication is that regional analysts should reassess the commonly felt need to update tables on a regular basis.

Dietary Vitamin and Stability of Oral Anticoagulation: Proposal of a Diet with Constant Vitamin K1 Content

1997 ◽  
Vol 77 (03) ◽  
pp. 504-509 ◽  
Author(s):  
Sarah L Booth ◽  
Jacqueline M Charnley ◽  
James A Sadowski ◽  
Edward Saltzman ◽  
Edwin G Bovill ◽  
...  
Keyword(s):  
Dietary Intake ◽  
Vitamin K ◽  
High Performance ◽  
Case Reports ◽  
Food Composition ◽  
Dietary Guidelines ◽  
Dietary Vitamin ◽  
Vitamin K1 ◽  
The Stability ◽  
The Impact

SummaryCase reports cited in Medline or Biological Abstracts (1966-1996) were reviewed to evaluate the impact of vitamin K1 dietary intake on the stability of anticoagulant control in patients using coumarin derivatives. Reported nutrient-drug interactions cannot always be explained by the vitamin K1 content of the food items. However, metabolic data indicate that a consistent dietary intake of vitamin K is important to attain a daily equilibrium in vitamin K status. We report a diet that provides a stable intake of vitamin K1, equivalent to the current U.S. Recommended Dietary Allowance, using food composition data derived from high-performance liquid chromatography. Inconsistencies in the published literature indicate that prospective clinical studies should be undertaken to clarify the putative dietary vitamin K1-coumarin interaction. The dietary guidelines reported here may be used in such studies.

IMPACT OF GOVERNMENT DEBT ON FINANCIAL SECURITY OF UKRAINE

2017 ◽  
Author(s):  
Olena Pikaliuk ◽  
◽  
Dmitry Kovalenko ◽  
Keyword(s):  
Economic Development ◽  
Public Debt ◽  
Positive Impact ◽  
The State ◽  
Financial Security ◽  
State Budget ◽  
The Public ◽  
Debt Security ◽  
The Stability ◽  
The Impact

One of the main criteria for economic development is the size of the public debt and its dynamics. The article considers the impact of public debt on the financial security of Ukraine. The views of scientists on the essence of public debt and financial security of the state are substantiated. An analysis of the dynamics and structure of public debt of Ukraine for 2014-2019. It is proved that one of the main criteria for economic development is the size of public debt and its dynamics. State budget deficit, attracting and using loans to cover it have led to the formation and significant growth of public debt in Ukraine. The volume of public debt indicates an increase in the debt security of the state, which is a component of financial security. Therefore, the issue of the impact of public debt on the financial security of Ukraine is becoming increasingly relevant. The constant growth and large amounts of debt make it necessary to study it, which will have a positive impact on economic processes that will ensure the stability of the financial system and enhance its security.

Polysaccharide Structures in the Outer Mucilage of Arabidopsis Seeds Visualized by AFM

2020 ◽  
Author(s):  
MAK Williams ◽  
V Cornuault ◽  
AH Irani ◽  
VV Symonds ◽  
J Malmström ◽  
...  
Keyword(s):  
Average Length ◽  
American Chemical Society ◽  
Md Simulations ◽  
Chemical Society ◽  
Side Chains ◽  
Rhamnogalacturonan I ◽  
Afm Imaging ◽  
Minor Population ◽  
The Stability ◽  
A Minor

© 2020 American Chemical Society. Evidence is presented that the polysaccharide rhamnogalacturonan I (RGI) can be biosynthesized in remarkably organized branched configurations and surprisingly long versions and can self-assemble into a plethora of structures. AFM imaging has been applied to study the outer mucilage obtained from wild-type (WT) and mutant (bxl1-3 and cesa5-1) Arabidopsis thaliana seeds. For WT mucilage, ordered, multichain structures of the polysaccharide RGI were observed, with a helical twist visible in favorable circumstances. Molecular dynamics (MD) simulations demonstrated the stability of several possible multichain complexes and the possibility of twisted fibril formation. For bxl1-3 seeds, the imaged polymers clearly showed the presence of side chains. These were surprisingly regular and well organized with an average length of ∼100 nm and a spacing of ∼50 nm. The heights of the side chains imaged were suggestive of single polysaccharide chains, while the backbone was on average 4 times this height and showed regular height variations along its length consistent with models of multichain fibrils examined in MD. Finally, in mucilage extracts from cesa5-1 seeds, a minor population of chains in excess of 30 μm long was observed.

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