Compressed sodium chloride as a fast-acting antimicrobial surface: results of a pilot study.

PubMed

Whitlock, B D; Smith, S W

2016-10-01

Antimicrobial surfaces are currently being studied as an aid to reduce transmission of pathogens leading to healthcare-associated infections (HAIs). Among the most harmful and costly pathogens that cause HAIs is meticillin-resistant Staphylococcus aureus (MRSA). Currently available and previously investigated antimicrobial surface technologies that are effective against MRSA (e.g. copper alloy surfaces) take 30min to several hours to achieve significant reduction. This article presents a new antimicrobial surface technology made of compressed sodium chloride that reduces MRSA 20-30 times faster than copper alloy surfaces. Copyright © 2016 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Efficacy of Ultraviolet (UV-C) Light in a Thin-Film Turbulent Flow for the Reduction of Milkborne Pathogens.

PubMed

Crook, Jennifer A; Rossitto, Paul V; Parko, Jared; Koutchma, Tatiana; Cullor, James S

2015-06-01

Nonthermal technologies are being investigated as viable alternatives to, or supplemental utilization, with thermal pasteurization in the food-processing industry. In this study, the effect of ultraviolet (UV)-C light on the inactivation of seven milkborne pathogens (Listeria monocytogenes, Serratia marcescens, Salmonella Senftenberg, Yersinia enterocolitica, Aeromonas hydrophila, Escherichia coli, and Staphylococcus aureus) was evaluated. The pathogens were suspended in ultra-high-temperature whole milk and treated at UV doses between 0 and 5000 J/L at a flow rate of 4300 L/h in a thin-film turbulent flow-through pilot system. Of the seven milkborne pathogens tested, L. monocytogenes was the most UV resistant, requiring 2000 J/L of UV-C exposure to reach a 5-log reduction. The most sensitive bacterium was S. aureus, requiring only 1450 J/L to reach a 5-log reduction. This study demonstrated that the survival curves were nonlinear. Sigmoidal inactivation curves were observed for all tested bacterial strains. Nonlinear modeling of the inactivation data was a better fit than the traditional log-linear approach. Results obtained from this study indicate that UV illumination has the potential to be used as a nonthermal method to reduce microorganism populations in milk.

Introducing Pathogen Reduction Technology in Poland: A Cost-Utility Analysis

PubMed Central

Agapova, Maria; Lachert, Elzbieta; Brojer, Ewa; Letowska, Magdalena; Grabarczyk, Piotr; Custer, Brian

2015-01-01

Background Mirasol® pathogen reduction technology (PRT) uses UV light and riboflavin to chemically inactivate pathogens and white blood cells in blood components. In the EU, Mirasol PRT is CE-marked for both plasma and platelet treatment. In Poland, the decision to introduce PRT treatment of the national supply of fresh frozen plasma has spurred interest in evaluating the cost-effectiveness of this strategy. Methods A decision-analytic model evaluated the incremental costs and benefits of introducing PRT to the existing blood safety protocols in Poland. Results Addition of PRT treatment of plasma to current screening in Poland is estimated to cost 2.595 million PLN per quality-adjusted life year (QALY) (610,000 EUR/QALY); treating both plasma and platelet components in addition to current safety interventions had a lower cost of 1.480 million PLN/QALY (348,000 EUR/QALY). Conclusions The results suggest that in Poland the cost per QALY of PRT is high albeit lower than found in previous economic analyses of PRT and nucleic acid testing in North America. Treating both platelets and plasma components is more cost-effective than treating plasma alone. Wide confidence intervals indicate high uncertainty; to improve the precision of the health economic evaluation of PRT, additional hemovigilance data are needed. PMID:26195929

Pathogen reduction and blood transfusion safety in Africa: strengths, limitations and challenges of implementation in low-resource settings.

PubMed

Ware, A D; Jacquot, C; Tobian, A A R; Gehrie, E A; Ness, P M; Bloch, E M

2018-01-01

Transfusion-transmitted infection risk remains an enduring challenge to blood safety in Africa. A high background incidence and prevalence of the major transfusion-transmitted infections (TTIs), dependence on high-risk donors to meet demand, suboptimal testing and quality assurance collectively contribute to the increased risk. With few exceptions, donor testing is confined to serological evaluation of human immunodeficiency virus (HIV), hepatitis B and C (HBV and HCV) and syphilis. Barriers to implementation of broader molecular methods include cost, limited infrastructure and lack of technical expertise. Pathogen reduction (PR), a term used to describe a variety of methods (e.g. solvent detergent treatment or photochemical activation) that may be applied to blood following collection, offers the means to diminish the infectious potential of multiple pathogens simultaneously. This is effective against different classes of pathogen, including the major TTIs where laboratory screening is already implemented (e.g. HIV, HBV and HCV) as well pathogens that are widely endemic yet remain unaddressed (e.g. malaria, bacterial contamination). We sought to review the available and emerging PR techniques and their potential application to resource-constrained parts of Africa, focusing on the advantages and disadvantages of such technologies. PR has been slow to be adopted even in high-income countries, primarily given the high costs of use. Logistical considerations, particularly in low-resourced parts of Africa, also raise concerns about practicality. Nonetheless, PR offers a rational, innovative strategy to contend with TTIs; technologies in development may well present a viable complement or even alternative to targeted screening in the future. © 2017 International Society of Blood Transfusion.

Use of cationic polymers to reduce pathogen levels during dairy manure separation.

PubMed

Liu, Zong; Carroll, Zachary S; Long, Sharon C; Gunasekaran, Sundaram; Runge, Troy

2016-01-15

Various separation technologies are used to deal with the enormous amounts of animal waste that large livestock operations generate. When the recycled waste stream is land applied, it is essential to lower the pathogen load to safeguard the health of livestock and humans. We investigated whether cationic polymers, used as a flocculent in the solid/liquid separation process, could reduce the pathogen indicator load in the animal waste stream. The effects of low charge density cationic polyacrylamide (CPAM) and high charge density cationic polydicyandiamide (PDCD) were investigated. Results demonstrated that CPAM was more effective than PDCD for manure coagulation and flocculation, while PDCD was more effective than CPAM in reducing the pathogen indicator loads. However, their combined use, CPAM followed by PDCD, resulted in both improved solids separation and pathogen indicator reduction. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

PATHOGEN REDUCTION WITH SUSTAINABLE AND APPROPRIATE TECHNOLOGY FOR A SECONDARY SCHOOL SANITATION FACILITY IN AZOVÉ, BENIN

EPA Science Inventory

A site visit to the CEG confirmed that water and sanitation are priorities of the school board and parents of the children at the school. Both the need and desire for clean water and improved sanitation was apparent. The skills and materials needed to build...

Genetics-based methods for detection of Salmonella spp. in foods.

PubMed

Mozola, Mark A

2006-01-01

Genetic methods are now at the forefront of foodborne pathogen testing. The sensitivity, specificity, and inclusivity advantages offered by deoxyribonucleic acid (DNA) probe technology have driven an intense effort in methods development over the past 20 years. DNA probe-based methods for Salmonella spp. and other pathogens have progressed from time-consuming procedures involving the use of radioisotopes to simple, high throughput, automated assays. The analytical sensitivity of nucleic acid amplification technology has facilitated a reduction in analysis time by allowing enriched samples to be tested for previously undetectable quantities of analyte. This article will trace the evolution of the development of genetic methods for detection of Salmonella in foods, review the basic assay formats and their advantages and limitations, and discuss method performance characteristics and considerations for selection of methods.

Intervention strategies for control of foodborne pathogens

NASA Astrophysics Data System (ADS)

Juneja, Vijay K.

2004-03-01

The increasing numbers of illnesses associated with foodborne pathogens such as Listeria monocytogenes and Escherichia coli O157:H7, has renewed concerns about food safety because of consumer preferences for minimally processed foods that offer convenience in availability and preparation. Accordingly, the need for better control of foodborne pathogens has been paramount in recent years. Mechanical removal of microorganisms from food can be accomplished by centrifugation, filtration, trimming and washing. Cleaning and sanitation strategies can be used for minimizing the access of microorganisms in foods from various sources. Other strategies for control of foodborne pathogens include established physical microbiocidal treatments such as ionizing radiation and heating. Research has continued to demonstrate that food irradiation is a suitable process to control and possibly eliminate foodborne pathogens, for example Listeria monocytogenes and Escherichia coli O157:H7, from a number of raw and cooked meat and poultry products. Heat treatment is the most common method in use today for the inactivation of microorganisms. Microorganisms can also be destroyed by nonthermal treatments, such as application of high hydrostatic pressure, pulsed electric fields, oscillating magnetic fields or a combination of physical processes such as heat-irradiation, or heat-high hydrostatic pressure, etc. Each of the non-thermal technologies has specific applications in terms of the types of food that can be processed. Both conventional and newly developed physical treatments can be used in combination for controlling foodborne pathogens and enhancing the safety and shelf life of foods. Recent research has focused on combining traditional preservation factors with emerging intervention technologies. However, many key issues still need to be addressed for combination preservation factors or technologies to be useful in the food industry to meet public demands for foods with enhanced safety, freshness and appeal. As a result of systematic study in these areas together with detailed assessment of technological performance of available preservatives and preservation technologies in real food formulations, new intervention processes and products are likely to be developed. The ultimate goal is to identify potential new approaches for the safer production of foods. The purpose of this presentation is to discuss key developmental activities concerning microbial reduction by intervention technologies.

Pathogen reduction in human plasma using an ultrashort pulsed laser

USDA-ARS?s Scientific Manuscript database

Pathogen reduction is an ideal approach to ensure the continued safety of the blood supply against emerging pathogens. However, the currently licensed pathogen reduction techniques are ineffective against non-enveloped viruses, and they introduce chemicals with concerns of side effects which prevent...

A comprehensive proteomics study on platelet concentrates: Platelet proteome, storage time and Mirasol pathogen reduction technology.

PubMed

Salunkhe, Vishal; De Cuyper, Iris M; Papadopoulos, Petros; van der Meer, Pieter F; Daal, Brunette B; Villa-Fajardo, María; de Korte, Dirk; van den Berg, Timo K; Gutiérrez, Laura

2018-03-19

Platelet concentrates (PCs) represent a blood transfusion product with a major concern for safety as their storage temperature (20-24°C) allows bacterial growth, and their maximum storage time period (less than a week) precludes complete microbiological testing. Pathogen inactivation technologies (PITs) provide an additional layer of safety to the blood transfusion products from known and unknown pathogens such as bacteria, viruses, and parasites. In this context, PITs, such as Mirasol Pathogen Reduction Technology (PRT), have been developed and are implemented in many countries. However, several studies have shown in vitro that Mirasol PRT induces a certain level of platelet shape change, hyperactivation, basal degranulation, and increased oxidative damage during storage. It has been suggested that Mirasol PRT might accelerate what has been described as the platelet storage lesion (PSL), but supportive molecular signatures have not been obtained. We aimed at dissecting the influence of both variables, that is, Mirasol PRT and storage time, at the proteome level. We present comprehensive proteomics data analysis of Control PCs and PCs treated with Mirasol PRT at storage days 1, 2, 6, and 8. Our workflow was set to perform proteomics analysis using a gel-free and label-free quantification (LFQ) approach. Semi-quantification was based on LFQ signal intensities of identified proteins using MaxQuant/Perseus software platform. Data are available via ProteomeXchange with identifier PXD008119. We identified marginal differences between Mirasol PRT and Control PCs during storage. However, those significant changes at the proteome level were specifically related to the functional aspects previously described to affect platelets upon Mirasol PRT. In addition, the effect of Mirasol PRT on the platelet proteome appeared not to be exclusively due to an accelerated or enhanced PSL. In summary, semi-quantitative proteomics allows to discern between proteome changes due to Mirasol PRT or PSL, and proves to be a methodology suitable to phenotype platelets in an unbiased manner, in various physiological contexts.

Air Purifiers Eliminate Pathogens, Preserve Food

NASA Technical Reports Server (NTRS)

2009-01-01

NASA-funded researchers produced an ethylene reduction device for a plant growth unit. KES Science & Technology Inc., a Kennesaw, Georgia-based company specializing in sustaining perishable foods, licensed the ethylene scrubbing technology. KES partnered with Akida Holdings, of Jacksonville, Florida, which now markets the NASA-developed technology as AiroCide. According to the company, it is the only air purifier that completely destroys airborne bacteria, mold, fungi, mycotoxins, viruses, volatile organic compounds (like ethylene), and odors. What?s more, the devices have no filters that need changing and produce no harmful byproducts, such as the ozone created by some filtration systems.

Treatment of blood with a pathogen reduction technology using ultraviolet light and riboflavin inactivates Ebola virus in vitro.

PubMed

Cap, Andrew P; Pidcoke, Heather F; Keil, Shawn D; Staples, Hilary M; Anantpadma, Manu; Carrion, Ricardo; Davey, Robert A; Frazer-Abel, Ashley; Taylor, Audra L; Gonzales, Richard; Patterson, Jean L; Goodrich, Raymond P

2016-03-01

Transfusion of plasma from recovered patients after Ebolavirus (EBOV) infection, typically called "convalescent plasma," is an effective treatment for active disease available in endemic areas, but carries the risk of introducing other pathogens, including other strains of EBOV. A pathogen reduction technology using ultraviolet light and riboflavin (UV+RB) is effective against multiple enveloped, negative-sense, single-stranded RNA viruses that are similar in structure to EBOV. We hypothesized that UV+RB is effective against EBOV in blood products without activating complement or reducing protective immunoglobulin titers that are important for the treatment of Ebola virus disease (EVD). Four in vitro experiments were conducted to evaluate effects of UV+RB on green fluorescent protein EBOV (EBOV-GFP), wild-type EBOV in serum, and whole blood, respectively, and on immunoglobulins and complement in plasma. Initial titers for Experiments 1 to 3 were 4.21 log GFP units/mL, 4.96 log infectious units/mL, and 4.23 log plaque-forming units/mL. Conditions tested in the first three experiments included the following: 1-EBOV-GFP plus UV+RB; 2-EBOV-GFP plus RB only; 3-EBOV-GFP plus UV only; 4-EBOV-GFP without RB or UV; 5-virus-free control plus UV only; and 6-virus-free control without RB or UV. UV+RB reduced EBOV titers to nondetectable levels in both nonhuman primate serum (≥2.8- to 3.2-log reduction) and human whole blood (≥3.0-log reduction) without decreasing protective antibody titers in human plasma. Our in vitro results demonstrate that the UV+RB treatment efficiently reduces EBOV titers to below limits of detection in both serum and whole blood. In vivo testing to determine whether UV+RB can improve convalescent blood product safety is indicated. © 2016 AABB.

Treatment of blood with a pathogen reduction technology using UV light and riboflavin inactivates Ebola virus in vitro

PubMed Central

Cap, Andrew P.; Pidcoke, Heather F.; Keil, Shawn D.; Staples, Hilary M.; Anantpadma, Manu; Carrion, Ricardo; Davey, Robert A.; Frazer-Abel, Ashley; Taylor, Audra L.; Gonzales, Richard; Patterson, Jean L.; Goodrich, Raymond P.

2018-01-01

BACKGROUND Transfusion of plasma from recovered patients after Ebolavirus (EBOV) infection, typically called ‘convalescent plasma,’ is an effective treatment for active disease available in endemic areas, but carries the risk of introducing other pathogens, including other strains of EBOV. A pathogen reduction technology using ultraviolet light and riboflavin (UV + RB) is effective against multiple enveloped, negative-sense, single-stranded RNA viruses that are similar in structure to EBOV. We hypothesized that UV + RB is effective against EBOV in blood products without activating complement or reducing protective immunoglobulin titers that are important for the treatment of ebolavirus disease (EVD). STUDY DESIGN AND METHODS Four in vitro experiments were conducted to evaluate effects of UV + RB on green fluorescent protein EBOV (EBOV-GFP), wild-type EBOV in serum and whole blood, respectively, and on immunoglobulins and complement in plasma. Initial titers for Experiments 1–3 were: 4.21 log10 GFP units/mL, 4.96 log10 infectious units per mL, and 4.23 log10 plaque forming units per mL (PFU/mL). Conditions tested in the first three experiments included: 1. EBOV-GFP + UV + RB; 2. EBOV-GFP + RB only; 3 EBOV-GFP + UV only; 4. EBOV-GFP without RB or UV; 5. Virus-free control + UV only; and 6. Virus-free control without RB or UV. RESULTS UV + RB reduced EBOV titers to non-detectable levels in both non-human primate serum (≥ 2.8 to 3.2 log reduction) and human whole blood (≥ 3.0 log reduction) without decreasing protective antibody titers in human plasma. CONCLUSION Our in vitro results demonstrate that the UV + RB treatment efficiently reduces EBOV titers to below limits of detection in both serum and whole blood. In vivo testing to determine whether UV + RB can improve convalescent blood product safety is indicated. PMID:27001363

Review of pathogen treatment reductions for onsite non ...

EPA Pesticide Factsheets

Communities face a challenge when implementing onsite reuse of collected waters for non-potable purposes given the lack of national microbial standards. Quantitative Microbial Risk Assessment (QMRA) can be used to predict the pathogen risks associated with the non-potable reuse of onsite-collected waters; the present work reviewed the relevant QMRA literature to prioritize knowledge gaps and identify health-protective pathogen treatment reduction targets. The review indicated that ingestion of untreated, onsite-collected graywater, rainwater, seepage water and stormwater from a variety of exposure routes resulted in gastrointestinal infection risks greater than the traditional acceptable level of risk. We found no QMRAs that estimated the pathogen risks associated with onsite, non-potable reuse of blackwater. Pathogen treatment reduction targets for non-potable, onsite reuse that included a suite of reference pathogens (i.e., including relevant bacterial, protozoan, and viral hazards) were limited to graywater (for a limited set of domestic uses) and stormwater (for domestic and municipal uses). These treatment reductions corresponded with the health benchmark of a probability of infection or illness of 10−3 per person per year or less. The pathogen treatment reduction targets varied depending on the target health benchmark, reference pathogen, source water, and water reuse application. Overall, there remains a need for pathogen reduction targets that are heal

Whole blood pathogen reduction technology and blood safety in sub-Saharan Africa: A systematic review with regional discussion

PubMed Central

Agbor, Gabriel; Asongalem, Emmanuel; Tagny, Claude; Asonganyi, Tazoacha

2016-01-01

Background Despite vast improvements in transfusion services in sub-Saharan Africa over the last decade, there remain serious concerns on the safety and adequacy of the blood supply across the region. Objective This review paper ascertains the role of pathogen reduction technology (PRT) in improving blood safety and supply adequacy in the region. Method The state of blood safety in sub-Saharan Africa was reviewed. Meetings, seminars and correspondence were undertaken with key clinicians, scientists and professional bodies in the region, including the World Health Organization’s Regional Office for Africa, to examine the suitability of PRT for improving the safety of whole blood transfusion, a prevalent transfusion format in the region. Results Existing literature suggests that combining PRT with current blood safety measures (such as serology) would improve the safety and adequacy of the blood supply for transfusions in sub-Saharan Africa. This was echoed by the findings of the stakeholder meetings. Conclusion Following a detailed appraisal of two leading PRT systems, the Mirasol® PRT System and the Cerus S-303 System, we suggest that companies conduct comprehensive toxicological evaluation of the agents used for PRT and publish this in the scientific literature. We also recommend that the safety and efficacy of these technologies should be established in a randomised clinical trial conducted in sub-Saharan Africa. PMID:28879109

Inactivation of foodborne pathogens in ground beef by cooking with highly controlled radio frequency energy.

PubMed

Schlisselberg, Dov B; Kler, Edna; Kalily, Emmanuel; Kisluk, Guy; Karniel, Ohad; Yaron, Sima

2013-01-01

The consumer demand for fresh tasting, high quality, low salt, preservative-free meals which require minimal preparation time magnifies the safety concern and emphasizes the need to use innovative technologies for food processing. A modern technique to uniformly heat and cook foods is based on a combination of convection and controlled radio frequency (RF) energy. However any advantage conferred on meat cooked by this method would be lost if application of the technology results in decreased safety. Our main goal was to study the inactivation efficacy of this method of cooking against pathogens in ground meat in comparison to standard convection cooking. Meat balls were artificially inoculated with GFP expressing Escherichia coli, Salmonella Typhimurium and Listeria monocytogenes as well as spores of Bacillus cereus and Bacillus thuringiensis and cooked by convection heating (220°C, 40 min), by using energy generated from frequencies in the RF bandwidth (RF cooking, 7.5 min) or by combined heating (5.5 min), until the center temperature of each sample reached 73°C. The mean reductions in total indigenous bacteria obtained by RF and convection were 2.8 and 2.5 log CFU/g, respectively. Cooking of meat balls with convection reduced the E. coli population (8 log CFU/g) by 5.5 log CFU/g, whilst treatment with RF reduced E. coli population to undetectable levels. The mean reductions of S. Typhimurium obtained by RF and convection were 5.7 and 6.5 log CFU/g, respectively. The combined treatment reduced the Salmonella population to undetectable levels. In contrast, L. monocytogenes was poorly affected by RF cooking. The mean reduction of L. monocytogenes obtained by RF energy was 0.4 log CFU/g, while convection cooking resulted in undetectable levels. Interestingly, the combined treatment also resulted with undetectable levels of Listeria although time of cooking was reduced by 86%. One-step cooking had negligible effects on the Bacillus spores and therefore a 2-step treatment of RF or convection was applied. This 2-step treatment proved to be efficient with 4.5 log CFU/g reduction for both RF and convection. In conclusion, here we show that combination of RF with convection cooking resulted in similar or even better effects on selected foodborne pathogens compared to convection only, while the time required for safe cooking is cut down by up to 86%. The equal or better results in the levels of all investigated pathogens using RF with convection compared with convection only suggest that this technology looks promising and safe for ground beef cooking. Copyright © 2012 Elsevier B.V. All rights reserved.

Disinfection and reduction of organic load of sewage water by electron beam radiation

NASA Astrophysics Data System (ADS)

Maruthi, Y. Avasn; Das, N. Lakshmana; Hossain, Kaizar; Sarma, K. S. S.; Rawat, K. P.; Sabharwal, S.

2011-09-01

The efficacy of electron beam radiation for the disinfection and reduction of organic load of sewage water was assessed with ILU-6 Accelerator at Radiation Technology Development Division of the Bhabha Atomic Research Centre, Mumbai India. The current problem on environmental health in relation to water pollution insists for the safe disposal of sewage water. In general, sewage water comprises heterogeneous organic based chemicals as well as pathogens. EB treatment of the wastewater has found to be very effective in reducing the pathogens as well as organic load. EB dose of 1.5 kGy was sufficient for complete elimination of total coli forms. The experimental results elucidated the reduction of biological oxygen demand—BOD (35 and 51.7%) in both inlet and outlet sewage samples. Similarly reduction of chemical oxygen demand—COD was observed (37.54 and 52.32%) in both sewage samples with respect to increase in irradiation doses (0.45-6 kGy). The present study demonstrated the potential of ionizing radiation for disinfection of sewage and to increase the water quality of the wastewater by decreasing BOD and COD. So, the irradiation sewage water can find its application either in agriculture for irrigation, in industry for cooling purpose and some selected domestic purposes.

Pathogen Reduction in Human Plasma Using an Ultrashort Pulsed Laser

PubMed Central

Tsen, Shaw-Wei D.; Kingsley, David H.; Kibler, Karen; Jacobs, Bert; Sizemore, Sara; Vaiana, Sara M.; Anderson, Jeanne; Tsen, Kong-Thon; Achilefu, Samuel

2014-01-01

Pathogen reduction is a viable approach to ensure the continued safety of the blood supply against emerging pathogens. However, the currently licensed pathogen reduction techniques are ineffective against non-enveloped viruses such as hepatitis A virus, and they introduce chemicals with concerns of side effects which prevent their widespread use. In this report, we demonstrate the inactivation of both enveloped and non-enveloped viruses in human plasma using a novel chemical-free method, a visible ultrashort pulsed laser. We found that laser treatment resulted in 2-log, 1-log, and 3-log reductions in human immunodeficiency virus, hepatitis A virus, and murine cytomegalovirus in human plasma, respectively. Laser-treated plasma showed ≥70% retention for most coagulation factors tested. Furthermore, laser treatment did not alter the structure of a model coagulation factor, fibrinogen. Ultrashort pulsed lasers are a promising new method for chemical-free, broad-spectrum pathogen reduction in human plasma. PMID:25372037

40 CFR 503.15 - Operational standards-pathogens and vector attraction reduction.

Code of Federal Regulations, 2011 CFR

2011-07-01

... vector attraction reduction. 503.15 Section 503.15 Protection of Environment ENVIRONMENTAL PROTECTION... § 503.15 Operational standards—pathogens and vector attraction reduction. (a) Pathogens—sewage sludge... reclamation site. (c) Vector attraction reduction—sewage sludge. (1) One of the vector attraction reduction...

The efficacy of Mentha arvensis L. and M. piperita L. essential oils in reducing pathogenic bacteria and maintaining quality characteristics in cashew, guava, mango, and pineapple juices.

PubMed

de Sousa Guedes, Jossana Pereira; da Costa Medeiros, José Alberto; de Souza E Silva, Richard Sidney; de Sousa, Janaína Maria Batista; da Conceição, Maria Lúcia; de Souza, Evandro Leite

2016-12-05

This study evaluated the ability of the essential oil from Mentha arvensis L. (MAEO) and M. piperita L. (MPEO) to induce ≥5-log reductions in counts (CFU/mL) of E. coli, L. monocytogenes, and Salmonella enterica serovar Enteritidis in Brain-Heart Infusion broth (BHIB) and cashew, guava, mango, and pineapple juices during refrigerated storage (4±0.5°C). The effects of the incorporation of these essential oils on some physicochemical and sensory parameters of juices were also evaluated. The incorporation of 5, 2.5, 1.25, or 0.625μL/mL of MAEO in BHIB caused a ≥5-log reduction in counts of E. coli and Salmonella Enteritidis after 24h of storage; but only 5μL/mL was able to cause the same reduction in counts of L.monocytogenes. The incorporation of 10μL/mL of MPEO in BHIB caused a ≥5-log reduction in counts of E. coli, Salmonella Enteritidis, and L. monocytogenes after 24h of storage; smaller reductions were observed in BHIB containing 5, 2.5, and 1.25μL/mL of MPEO. Similar reductions were observed when the MAEO or MPEO was incorporated at the same concentrations in mango juice. The incorporation of MAEO or MPEO at all tested concentrations in cashew, guava, and pineapple juices resulted in a ≥5-log reduction in pathogen counts within 1h. The incorporation of MAEO and MPEO (0.625 and 1.25μL/mL, respectively) in fruit juices did not induce alterations in °Brix, pH, and acidity, but negatively affected the taste, aftertaste, and overall acceptance. The use of MAEO or MPEO at low concentrations could constitute an interesting tool to achieve the required 5-log reduction of pathogenic bacteria in cashew, guava, mango, and pineapple fruit juices. However, new methods combining the use of MAEO or MPEO with other technologies are necessary to reduce their negative impacts on specific sensory properties of these juices. Copyright © 2016 Elsevier B.V. All rights reserved.

Predicting the Quality of Pasteurized Vegetables Using Kinetic Models: A Review

PubMed Central

Aamir, Muhammad; Ovissipour, Mahmoudreza; Sablani, Shyam S.; Rasco, Barbara

2013-01-01

A resurgence in interest examining thermal pasteurization technologies has been driven by demands for “cleaner” labeling and the need of organic and natural foods markets for suitable preventive measures to impede microbial growth and extend shelf life of minimally processed foods and ready-to-eat foods with a concomitant reduction in the use of chemical preservatives. This review describes the effects of thermal pasteurization on vegetable quality attributes including altering flavor and texture to improve consumer acceptability, stabilizing color, improving digestibility, palatability and retaining bioavailability of important nutrients, and bioactive compounds. Here, we provide kinetic parameters for inactivation of viral and bacterial pathogens and their surrogates and marker enzymes used to monitor process effectiveness in a variety of plant food items. Data on thermal processing protocols leading to higher retention and bioactivity are also presented. Thermal inactivation of foodborne viruses and pathogenic bacteria, specifically at lower pasteurization temperatures or via new technologies such as dielectric heating, can lead to greater retention of “fresh-like” properties. PMID:26904594

40 CFR 503.25 - Operational standards-pathogens and vector attraction reduction.

Code of Federal Regulations, 2010 CFR

2010-07-01

... vector attraction reduction. 503.25 Section 503.25 Protection of Environment ENVIRONMENTAL PROTECTION... § 503.25 Operational standards—pathogens and vector attraction reduction. (a) Pathogens—sewage sludge... active sewage sludge unit, unless the vector attraction reduction requirement in § 503.33(b)(11) is met...

40 CFR 503.25 - Operational standards-pathogens and vector attraction reduction.

Code of Federal Regulations, 2011 CFR

2011-07-01

... vector attraction reduction. 503.25 Section 503.25 Protection of Environment ENVIRONMENTAL PROTECTION... § 503.25 Operational standards—pathogens and vector attraction reduction. (a) Pathogens—sewage sludge... active sewage sludge unit, unless the vector attraction reduction requirement in § 503.33(b)(11) is met...

Role of ultraviolet (UV) disinfection in infection control and environmental cleaning.

PubMed

Qureshi, Zubair; Yassin, Mohamed H

2013-06-01

Ultraviolet (UV) radiation is capable of disinfecting surfaces, water and air. The UV technology was used for many years. However, safer and more effective delivery systems of UV radiation, make it a very useful option for disinfection. Effective disinfection of environmental surfaces is a key step in the prevention of spread of infectious agents. The traditional manual cleaning is essential in assuring adequate elimination of contamination. However, terminal cleaning is frequently suboptimal or unpredictable in many circumstances. UV-C radiation is an adjunctive disinfectant new technology that could kill a wide array of microorganisms including both vegetative and spore forming pathogens. The technology is getting more affordable and has produced consistent reproducible significant reduction of bacterial contamination.

Antimicrobial food packaging: potential and pitfalls

PubMed Central

Malhotra, Bhanu; Keshwani, Anu; Kharkwal, Harsha

2015-01-01

Nowadays food preservation, quality maintenance, and safety are major growing concerns of the food industry. It is evident that over time consumers’ demand for natural and safe food products with stringent regulations to prevent food-borne infectious diseases. Antimicrobial packaging which is thought to be a subset of active packaging and controlled release packaging is one such promising technology which effectively impregnates the antimicrobial into the food packaging film material and subsequently delivers it over the stipulated period of time to kill the pathogenic microorganisms affecting food products thereby increasing the shelf life to severe folds. This paper presents a picture of the recent research on antimicrobial agents that are aimed at enhancing and improving food quality and safety by reduction of pathogen growth and extension of shelf life, in a form of a comprehensive review. Examination of the available antimicrobial packaging technologies is also presented along with their significant impact on food safety. This article entails various antimicrobial agents for commercial applications, as well as the difference between the use of antimicrobials under laboratory scale and real time applications. Development of resistance amongst microorganisms is considered as a future implication of antimicrobials with an aim to come up with actual efficacies in extension of shelf life as well as reduction in bacterial growth through the upcoming and promising use of antimicrobials in food packaging for the forthcoming research down the line. PMID:26136740

Pathogen reduction co-benefits of nutrient best management practices

PubMed Central

Wainger, Lisa A.; Barber, Mary C.

2016-01-01

Background Many of the practices currently underway to reduce nitrogen, phosphorus, and sediment loads entering the Chesapeake Bay have also been observed to support reduction of disease-causing pathogen loadings. We quantify how implementation of these practices, proposed to meet the nutrient and sediment caps prescribed by the Total Maximum Daily Load (TMDL), could reduce pathogen loadings and provide public health co-benefits within the Chesapeake Bay system. Methods We used published data on the pathogen reduction potential of management practices and baseline fecal coliform loadings estimated as part of prior modeling to estimate the reduction in pathogen loadings to the mainstem Potomac River and Chesapeake Bay attributable to practices implemented as part of the TMDL. We then compare the estimates with the baseline loadings of fecal coliform loadings to estimate the total pathogen reduction potential of the TMDL. Results We estimate that the TMDL practices have the potential to decrease disease-causing pathogen loads from all point and non-point sources to the mainstem Potomac River and the entire Chesapeake Bay watershed by 19% and 27%, respectively. These numbers are likely to be underestimates due to data limitations that forced us to omit some practices from analysis. Discussion Based on known impairments and disease incidence rates, we conclude that efforts to reduce nutrients may create substantial health co-benefits by improving the safety of water-contact recreation and seafood consumption. PMID:27904807

Pathogen reduction co-benefits of nutrient best management practices.

PubMed

Richkus, Jennifer; Wainger, Lisa A; Barber, Mary C

2016-01-01

Many of the practices currently underway to reduce nitrogen, phosphorus, and sediment loads entering the Chesapeake Bay have also been observed to support reduction of disease-causing pathogen loadings. We quantify how implementation of these practices, proposed to meet the nutrient and sediment caps prescribed by the Total Maximum Daily Load (TMDL), could reduce pathogen loadings and provide public health co-benefits within the Chesapeake Bay system. We used published data on the pathogen reduction potential of management practices and baseline fecal coliform loadings estimated as part of prior modeling to estimate the reduction in pathogen loadings to the mainstem Potomac River and Chesapeake Bay attributable to practices implemented as part of the TMDL. We then compare the estimates with the baseline loadings of fecal coliform loadings to estimate the total pathogen reduction potential of the TMDL. We estimate that the TMDL practices have the potential to decrease disease-causing pathogen loads from all point and non-point sources to the mainstem Potomac River and the entire Chesapeake Bay watershed by 19% and 27%, respectively. These numbers are likely to be underestimates due to data limitations that forced us to omit some practices from analysis. Based on known impairments and disease incidence rates, we conclude that efforts to reduce nutrients may create substantial health co-benefits by improving the safety of water-contact recreation and seafood consumption.

76 FR 30176 - Expedited Review for New Animal Drug Applications for Human Pathogen Reduction Claims; Withdrawal...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-24

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2001-D-0066] (Formerly Docket No. 2001D-0107) Expedited Review for New Animal Drug Applications for Human Pathogen... Review for New Animal Drug Applications for Human Pathogen Reduction Claims.'' The guidance predates the...

Riboflavin-ultraviolet light pathogen reduction treatment does not impact the immunogenicity of murine red blood cells.

PubMed

Tormey, Christopher A; Santhanakrishnan, Manjula; Smith, Nicole H; Liu, Jingchun; Marschner, Susanne; Goodrich, Raymond P; Hendrickson, Jeanne E

2016-04-01

Ultraviolet (UV) illumination/pathogen reduction effectively inactivates white blood cells (WBCs) in whole blood. Given that cotransfused WBCs may impact recipient immune responses, we hypothesized that pathogen reduction of whole blood may alter responses to RBC antigens. Transgenic mice expressing a model (HOD) antigen, authentic human (hGPA or KEL) antigens, or natural fluorescence (uGFP) on their RBCs were utilized as blood donors. Recipients were transfused with fresh whole blood to which riboflavin had been added or fresh whole blood treated by UV illumination/pathogen reduction treatment after the addition of riboflavin. Posttransfusion RBC recovery, survival, and alloimmunization were measured by flow cytometry. UV illumination/pathogen reduction treatment did not alter RBC antigen expression, and recipients of treated syngeneic RBCs had persistently negative direct antiglobulin tests. Greater than 75% of treated and untreated syngeneic RBCs were recovered 24 hours posttransfusion in all experiments, although alterations in the long-term posttransfusion survival of treated RBCs were observed. Treated and untreated KEL RBCs induced similar recipient alloimmune responses, with all recipients making anti-KEL glycoprotein immunoglobulins (p > 0.05). Alloimmune responses to treated HOD or hGPA RBCs were no different from untreated RBCs (p > 0.05). Pathogen inactivation treatment of fresh whole murine blood with riboflavin and UV illumination does not impact the rate or magnitude of RBC alloimmunization to three distinct RBC antigens. Further, UV illumination/pathogen reduction appears safe from an immunohematologic standpoint, with no immunogenic neoantigens detected on treated murine RBCs. Future studies with fresh and stored human RBCs are warranted to confirm these findings. © 2015 AABB.

Tensor sufficient dimension reduction

PubMed Central

Zhong, Wenxuan; Xing, Xin; Suslick, Kenneth

2015-01-01

Tensor is a multiway array. With the rapid development of science and technology in the past decades, large amount of tensor observations are routinely collected, processed, and stored in many scientific researches and commercial activities nowadays. The colorimetric sensor array (CSA) data is such an example. Driven by the need to address data analysis challenges that arise in CSA data, we propose a tensor dimension reduction model, a model assuming the nonlinear dependence between a response and a projection of all the tensor predictors. The tensor dimension reduction models are estimated in a sequential iterative fashion. The proposed method is applied to a CSA data collected for 150 pathogenic bacteria coming from 10 bacterial species and 14 bacteria from one control species. Empirical performance demonstrates that our proposed method can greatly improve the sensitivity and specificity of the CSA technique. PMID:26594304

75 FR 30844 - General Mills, Inc.; Withdrawal of Food Additive Petition

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-02

... for the reduction of pathogens and other microorganisms in aqueous sugar solutions and potable water... reduction of pathogens and other microorganisms in aqueous sugar solutions and potable water intended for...

Efficacy of Combined Sous Vide-Microwave Cooking for Foodborne Pathogen Inactivation in Ready-to-Eat Chicory Stems.

PubMed

Renna, Massimiliano; Gonnella, Maria; de Candia, Silvia; Serio, Francesco; Baruzzi, Federico

2017-07-01

There is a variety of different food processing methods, which can be used to prepare ready-to-eat foods. However, the need to preserve the freshness and nutritional qualities leads to the application of mild technologies which may be insufficient to inactivate microbial pathogens. In this work, fresh chicory stems were packed under a vacuum in films, which were transparent to microwaves. These were then exposed to microwaves for different periods of time. The application of sous vide microwave cooking (SV-MW, 900 W, 2450 MHz), controlled naturally occurring mesophilic aerobic bacteria, yeasts and molds for up to 30 d when vacuum-packed vegetables were stored at 4 °C. In addition, the process lethality of the SV-MW 90 s cooking was experimentally validated. This treatment led to 6.07 ± 0.7 and 4.92 ± 0.65 log cfu/g reduction of Escherichia coli and Listeria monocytogenes inoculated over the chicory stems (100 g), respectively. With an initial load of 9 log cfu/g for both pathogens, less than 10 cfu/g of surviving cells were found after 90 s cooking. This shows that short-time microwave cooking can be used to effectively pasteurize vacuum-packed chicory stems, achieving >5 log cfu/g reduction of E. coli and L. monocytogenes. © 2017 Institute of Food Technologists®.

Development of a DNA Microarray-Based Assay for the Detection of Sugar Beet Root Rot Pathogens.

PubMed

Liebe, Sebastian; Christ, Daniela S; Ehricht, Ralf; Varrelmann, Mark

2016-01-01

Sugar beet root rot diseases that occur during the cropping season or in storage are accompanied by high yield losses and a severe reduction of processing quality. The vast diversity of microorganism species involved in rot development requires molecular tools allowing simultaneous identification of many different targets. Therefore, a new microarray technology (ArrayTube) was applied in this study to improve diagnosis of sugar beet root rot diseases. Based on three marker genes (internal transcribed spacer, translation elongation factor 1 alpha, and 16S ribosomal DNA), 42 well-performing probes enabled the identification of prevalent field pathogens (e.g., Aphanomyces cochlioides), storage pathogens (e.g., Botrytis cinerea), and ubiquitous spoilage fungi (e.g., Penicillium expansum). All probes were proven for specificity with pure cultures from 73 microorganism species as well as for in planta detection of their target species using inoculated sugar beet tissue. Microarray-based identification of root rot pathogens in diseased field beets was successfully confirmed by classical detection methods. The high discriminatory potential was proven by Fusarium species differentiation based on a single nucleotide polymorphism. The results demonstrate that the ArrayTube constitute an innovative tool allowing a rapid and reliable detection of plant pathogens particularly when multiple microorganism species are present.

40 CFR 503.15 - Operational standards-pathogens and vector attraction reduction.

Code of Federal Regulations, 2014 CFR

2014-07-01

... met when bulk sewage sludge is applied to a lawn or a home garden. (3) The Class A pathogen... home garden. (3) One of the vector attraction reduction requirements in § 503.33 (b)(1) through (b)(8...

40 CFR 503.15 - Operational standards-pathogens and vector attraction reduction.

Code of Federal Regulations, 2013 CFR

2013-07-01

... met when bulk sewage sludge is applied to a lawn or a home garden. (3) The Class A pathogen... home garden. (3) One of the vector attraction reduction requirements in § 503.33 (b)(1) through (b)(8...

40 CFR 503.15 - Operational standards-pathogens and vector attraction reduction.

Code of Federal Regulations, 2012 CFR

2012-07-01

... met when bulk sewage sludge is applied to a lawn or a home garden. (3) The Class A pathogen... home garden. (3) One of the vector attraction reduction requirements in § 503.33 (b)(1) through (b)(8...

Oxygen removal during pathogen inactivation with riboflavin and UV light preserves protein function in plasma for transfusion.

PubMed

Feys, H B; Van Aelst, B; Devreese, K; Devloo, R; Coene, J; Vandekerckhove, P; Compernolle, V

2014-05-01

Photochemical pathogen inactivation technologies (PCT) for individual transfusion products act by inhibition of replication through irreversibly damaging nucleic acids. Concern on the collateral impact of PCT on the blood component's integrity has caused reluctance to introduce this technology in routine practice. This work aims to uncover the mechanism of damage to plasma constituents by riboflavin pathogen reduction technology (RF-PRT). Activity and antigen of plasma components were determined following RF-PRT in the presence or absence of dissolved molecular oxygen. Employing ADAMTS13 as a sentinel molecule in plasma, our data show that its activity and antigen are reduced by 23 ± 8% and 29 ± 9% (n = 24), respectively, which corroborates with a mean decrease of 25% observed for other coagulation factors. Western blotting of ADAMTS13 shows decreased molecular integrity, with no obvious indication of additional proteolysis nor is riboflavin able to directly inhibit the enzyme. However, physical removal of dissolved oxygen prior to RF-PRT protects ADAMTS13 as well as FVIII and fibrinogen from damage, indicating a direct role for reactive oxygen species. Redox dye measurements indicate that superoxide anions are specifically generated during RF-PRT. Protein carbonyl content as a marker of disseminated irreversible biomolecular damage was significantly increased (3·1 ± 0·8 vs. 1·6 ± 0·5 nmol/mg protein) following RF-PRT, but not in the absence of dissolved molecular oxygen (1·8 ± 0·4 nmol/mg). RF-PRT of single plasma units generates reactive oxygen species that adversely affect biomolecular integrity of relevant plasma constituents, a side-effect, which can be bypassed by applying hypoxic conditions during the pathogen inactivation process. © 2013 International Society of Blood Transfusion.

Insecticide-treated clothes for the control of vector-borne diseases: a review on effectiveness and safety.

PubMed

Banks, S D; Murray, N; Wilder-Smith, A; Logan, J G

2014-08-01

Insecticide-treated clothing has been used for many years by the military and in recreational activities as personal protection against bites from a variety of arthropods including ticks, chigger mites, sandflies and mosquitoes. Permethrin is the most commonly used active ingredient, but others, including bifenthrin, deltamethrin, cyfluthrin, DEET (N,N-diethyl-3-methylbenz-amide) and KBR3023, have also been trialled. Treatment is usually carried out by home or factory dipping. However, new microencapsulation technologies which may prolong the activity of insecticides on clothing are now available and may help to overcome the inevitable reduction in efficacy over time that occurs as a result of washing, ultraviolet light exposure, and the normal wear and tear of the fabric. The aim of this article is to review the evidence base for the use of insecticide-treated clothing for protection against bites from arthropods and its effect on arthropod-borne pathogen transmission. Although some studies do demonstrate protection against pathogen transmission, there are surprisingly few, and the level of protection provided varies according to the disease and the type of study conducted. For example, insecticide-treated clothing has been reported to give between 0% and 75% protection against malaria and between 0% and 79% protection against leishmaniasis. Studies vary in the type of treatment used, the age group of participants, the geographical location of the study, and the pathogen transmission potential. This makes it difficult to compare and assess intervention trials. Overall, there is substantial evidence that insecticide-treated clothing can provide protection against arthropod bites. Bite protection evidence suggests that insecticide-treated clothing may be useful in the prevention of pathogen transmission, but further investigations are required to accurately demonstrate transmission reduction. © 2014 The Royal Entomological Society.

Risk-based enteric pathogen reduction targets for non-potable ...

EPA Pesticide Factsheets

This paper presents risk-based enteric pathogen log reduction targets for non-potable and potable uses of a variety of alternative source waters (i.e., locally-collected greywater, roof runoff, and stormwater). A probabilistic Quantitative Microbial Risk Assessment (QMRA) was used to derive the pathogen log10 reduction targets (LRTs) that corresponded with an infection risk of either 10−4 per person per year (ppy) or 10−2 ppy. The QMRA accounted for variation in pathogen concentration and sporadic pathogen occurrence (when data were available) in source waters for reference pathogens in the genera Rotavirus, Mastadenovirus (human adenoviruses), Norovirus, Campylobacter, Salmonella, Giardia and Cryptosporidium. Non-potable uses included indoor use (for toilet flushing and clothes washing) with occasional accidental ingestion of treated non-potable water (or cross-connection with potable water), and unrestricted irrigation for outdoor use. Various exposure scenarios captured the uncertainty from key inputs, i.e., the pathogen concentration in source water; the volume of water ingested; and for the indoor use, the frequency of and the fraction of the population exposed to accidental ingestion. Both potable and non-potable uses required pathogen treatment for the selected waters and the LRT was generally greater for potable use than non-potable indoor use and unrestricted irrigation. The difference in treatment requirements among source waters was driven by the

The gastrointestinal microbiome and its association with the control of pathogens in broiler chicken production: A review

PubMed Central

Clavijo, Viviana

2018-01-01

Abstract The microbiome of the broiler chicken gastrointestinal tract (GIT) has been extensively studied, and it has been amply demonstrated that it plays an important role in the health of the host, as it has a positive impact on the immune system, the physiology of the GIT, and productivity. Also, the microbiota is involved in reducing and preventing colonization by enteric pathogens through the process of competitive exclusion and the production of bacteriostatic and bactericidal substances. The taxonomic composition of the microbiota is affected by different factors, such as the organ, the age of the animal, diet and the use of antimicrobials. Different kinds of additives that regulate the microbial community in feed include probiotics (live microorganisms that when administered in adequate amounts confer a health benefit on the host), prebiotics (ingredients that stimulate increased beneficial microbial activity in the digestive system in order to improve the health of the host) and phytobiotics (primary or secondary components of plants that contain bioactive compounds that exert a positive effect on the growth and health of animals). Phages may potentially provide an integrated solution to modulate the intestinal microbiome of chicken intestines, as they reduce specific pathogenic microbial populations, permitting the proliferation of beneficial microbiota. Studies have shown that the use of cocktails of phages, especially in high concentrations and with short lapses of time between exposure to the bacteria and treatment with phages, optimize the reduction of Salmonella in chickens. Each of these technologies has demonstrable positive effects on the health of the host and the reduction of the pathogen load in controlled assays. This paper presents a comprehensive summary of the role of the microbiota in the broiler chicken gastrointestinal tract, and discusses the usefulness of different strategies for its modulation to control pathogens, with a particular emphasis on bacteriophages. PMID:29253263

Removal of pathogenic bacteria from sewage-treated effluent and biosolids for agricultural purposes

NASA Astrophysics Data System (ADS)

Al-Gheethi, A. A.; Efaq, A. N.; Bala, J. D.; Norli, I.; Abdel-Monem, M. O.; Ab. Kadir, M. O.

2018-05-01

The reuse of treated sewage for irrigation is considered as an important alternative water source in the new water management strategy of the countries that face a severe deficiency of water resources such as the Middle East countries. The organic material and fertilizing elements contained in biosolids are essential for maintaining soil fertility. However, both treated sewage and biosolids contain a large diversity of pathogens that would be transmitted to the environment and infect human directly or indirectly. Therefore, those pathogens should be reduced from the treated sewage and biosolids before the reuse in the agriculture. This paper reviews the considerations for reuse of treated sewage and biosolids in agriculture and further treatments used for reduction of pathogenic bacteria. The treatment methods used for the reduction of pathogens in these wastes have reviewed. It appeared that the main concern associated with the reduction of pathogenic bacteria lies in their ability to regrow in the treated sewage and biosolids. Therefore, the effective treatment method is that it has the potential to destruct pathogens cells and remove the nutrients to prevent the regrowth or recontamination from the surrounded environment. The removal of nutrients might be applicable in the sewage but not in the biosolids due to high nutrient contents. However, the reduction of health risk in the biosolids might be carried out by regulating the biosolid utilization and selecting the plant species grown in the fertilized soil with biosolids.

Cold plasma inactivates Salmonella Stanley and Escherichia coli O157:H7 inoculated on golden delicious apples.

PubMed

Niemira, Brendan A; Sites, Joseph

2008-07-01

Cold plasma generated in a gliding arc was applied to outbreak strains of Escherichia coli O157:H7 and Salmonella Stanley on agar plates and inoculated onto the surfaces of Golden Delicious apples. This novel sanitizing technology inactivated both pathogens on agar plates, with higher flow rate (40 liters/min) observed to be more efficacious than were lower flow rates (20 liters/min), irrespective of treatment time (1 or 2 min). Golden Delicious apples were treated with various flow rates (10, 20, 30, or 40 liters/min) of cold plasma for various times (1, 2, or 3 min), applied to dried spot inoculations. All treatments resulted in significant (P < 0.05) reductions from the untreated control, with 40 liters/min more effective than were lower flow rates. Inactivation of Salmonella Stanley followed a time-dependent reduction for all flow rates. Reductions after 3 min ranged from 2.9 to 3.7 log CFU/ml, close to the limit of detection. For E. coli O157:H7, 40 liters/min gave similar reductions for all treatment times, 3.4 to 3.6 log CFU/ml. At lower flow rates, inactivation was related to exposure time, with 3 min resulting in reductions of 2.6 to 3 log CFU/ml. Temperature increase of the treated apples was related to exposure time for all flow rates. The maximum temperature of any plasma-treated apple was 50.8 degrees C (28 degrees C above ambient), after 20 liters/min for 3 min, indicating that antimicrobial effects were not the result of heat. These results indicate that cold plasma is a nonthermal process that can effectively reduce human pathogens inoculated onto fresh produce.

Decontamination of indoor air to reduce the risk of airborne infections: Studies on survival and inactivation of airborne pathogens using an aerobiology chamber.

PubMed

Sattar, Syed A; Kibbee, Richard J; Zargar, Bahram; Wright, Kathryn E; Rubino, Joseph R; Ijaz, M Khalid

2016-10-01

Although indoor air can spread many pathogens, information on the airborne survival and inactivation of such pathogens remains sparse. Staphylococcus aureus and Klebsiella pneumoniae were nebulized separately into an aerobiology chamber (24.0 m 3 ). The chamber's relative humidity and air temperature were at 50% ± 5% and 20°C ± 2°C, respectively. The air was sampled with a slit-to-agar sampler. Between tests, filtered air purged the chamber of any residual airborne microbes. The challenge in the air varied between 4.2 log 10 colony forming units (CFU)/m 3 and 5.0 log 10 CFU/m 3 , sufficient to show a ≥3 log 10 (≥99.9%) reduction in microbial viability in air over a given contact time by the technologies tested. The rates of biologic decay of S aureus and K pneumoniae were 0.0064 ± 0.00015 and 0.0244 ± 0.009 log 10 CFU/m 3 /min, respectively. Three commercial devices, with ultraviolet light and HEPA (high-efficiency particulate air) filtration, met the product efficacy criterion in 45-210 minutes; these rates were statistically significant compared with the corresponding rates of biologic decay of the bacteria. One device was also tested with repeated challenges with aerosolized S aureus to simulate ongoing fluctuations in indoor air quality; it could reduce each such recontamination to an undetectable level in approximately 40 minutes. The setup described is suitable for work with all major classes of pathogens and also complies with the U.S. Environmental Protection Agency's guidelines (2012) for testing air decontamination technologies. Copyright © 2016 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

LITERATURE REVIEW OF MOLECULAR METHODS FOR SIMULTANEOUS DETECTION OF PATHOGENS IN WATER

EPA Science Inventory

This literature search is a review of molecular technologies (qPCR, microarray, microfluidics and lab-on-a-chip) for simultaneous detection of multiple waterborne pathogens in order to understand the state of the technology. The search content focuses on: pathogen detection witho...

Green chemistry in protected horticulture: the use of peroxyacetic acid as a sustainable strategy.

PubMed

Carrasco, Gilda; Urrestarazu, Miguel

2010-05-03

Global reduction of chemical deposition into the environment is necessary. In protected horticulture, different strategies with biodegradable products are used to control pathogens. This review presents the available tools, especially for the management of protected horticultural species, including vegetables and ornamental plants. An analysis of the potential for degradable products that control pathogens and also encourage other productive factors, such as oxygen in the root system, is presented. Biosecurity in fertigation management of protected horticulture is conducted by using peroxyacetic acid mixtures that serve three basic principles: first, the manufacture of these products does not involve polluting processes; second, they have the same function as other chemicals, and third, after use and management there is no toxic residue left in the environment. The sustainability of protected horticulture depends on the development and introduction of technologies for implementation in the field.

Green Chemistry in Protected Horticulture: The Use of Peroxyacetic Acid as a Sustainable Strategy

PubMed Central

Carrasco, Gilda; Urrestarazu, Miguel

2010-01-01

Global reduction of chemical deposition into the environment is necessary. In protected horticulture, different strategies with biodegradable products are used to control pathogens. This review presents the available tools, especially for the management of protected horticultural species, including vegetables and ornamental plants. An analysis of the potential for degradable products that control pathogens and also encourage other productive factors, such as oxygen in the root system, is presented. Biosecurity in fertigation management of protected horticulture is conducted by using peroxyacetic acid mixtures that serve three basic principles: first, the manufacture of these products does not involve polluting processes; second, they have the same function as other chemicals, and third, after use and management there is no toxic residue left in the environment. The sustainability of protected horticulture depends on the development and introduction of technologies for implementation in the field. PMID:20559497

Microbial minimalism: genome reduction in bacterial pathogens.

PubMed

Moran, Nancy A

2002-03-08

When bacterial lineages make the transition from free-living or facultatively parasitic life cycles to permanent associations with hosts, they undergo a major loss of genes and DNA. Complete genome sequences are providing an understanding of how extreme genome reduction affects evolutionary directions and metabolic capabilities of obligate pathogens and symbionts.

Multiplex cytokine profiling with highly pathogenic material: use of formalin solution in luminex analysis.

PubMed

Dowall, Stuart D; Graham, Victoria A; Tipton, Thomas R W; Hewson, Roger

2009-08-31

Work with highly pathogenic material mandates the use of biological containment facilities, involving microbiological safety cabinets and specialist laboratory engineering structures typified by containment level 3 (CL3) and CL4 laboratories. Consequences of working in high containment are the practical difficulties associated with containing specialist assays and equipment often essential for experimental analyses. In an era of increased interest in biodefence pathogens and emerging diseases, immunological analysis has developed rapidly alongside traditional techniques in virology and molecular biology. For example, in order to maximise the use of small sample volumes, multiplexing has become a more popular and widespread approach to quantify multiple analytes simultaneously, such as cytokines and chemokines. The luminex microsphere system allows for the detection of many cytokines and chemokines in a single sample, but the detection method of using aligned lasers and fluidics means that samples often have to be analysed in low containment facilities. In order to perform cytokine analysis in materials from high containment (CL3 and CL4 laboratories), we have developed an appropriate inactivation methodology after staining steps, which although results in a reduction of median fluorescent intensity, produces statistically comparable outcomes when judged against non-inactivated samples. This methodology thus extends the use of luminex technology for material that contains highly pathogenic biological agents.

Estimating the Effectiveness of Imidacloprid When Used to Suppress Transmission of Tomato spotted wilt orthotospovirus in Commercial Agriculture.

PubMed

Chappell, Thomas M; Kennedy, George G

2018-06-21

Imidacloprid is widely used to manage tomato spotted wilt disease (TSW) in tobacco, tomato, and pepper, caused by Tomato spotted wilt orthotospovirus (TSWV) and spread by the tobacco thrips, Frankliniella fusca Hinds (Thysanoptera: Thripidae). Imidacloprid suppresses transmission of TSWV by reducing probing and feeding by adult thrips on treated plants, thereby reducing the probability of transmission by infectious thrips. Because imidacloprid does not reduce probing and feeding on treated plants to zero, the reduction in transmission probability per viruliferous thrips can be offset by an increase in the number of viruliferous thrips challenging treated plants. A composite of these effects which we call 'pathogen pressure' experienced by plants is a function of thrips population size, the proportion of those thrips that are viruliferous, and the probability that viruliferous thrips successfully inoculate plants. To better understand the relationship between imidacloprid's effect on virus transmission, pathogen pressure, and TSW incidence in tobacco, we modeled TSW incidence as a function of the two most important variables affecting components of pathogen pressure, temperature, and precipitation, and the dependence of imidacloprid's effect on pathogen pressure. A model incorporating imidacloprid's effect as a reduction in pathogen pressure was found to be more descriptive than models incorporating the effect as a reduction in TSW incidence. Results reveal maximum proportional reduction in TSW incidence resulting from imidacloprid use is associated with minimal potential TSW incidence. As pathogen pressure increases, potential TSW incidence approaches 100%, and the benefits of imidacloprid use are highest at intermediate levels of pathogen pressure.

Global Positioning Systems (GPS) Technology to Study Vector-Pathogen-Host Interactions

DTIC Science & Technology

2016-12-01

Award Number: W81XWH-11-2-0175 TITLE: Global Positioning Systems (GPS) Technology to Study Vector-Pathogen-Host Interactions PRINCIPAL...Positioning Systems (GPS) Technology to Study Vector-Pathogen-Host Interactions 5b. GRANT NUMBER W81XWH-11-2-0175 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S...objective of this project is to examine the evolutionary consequences of introducing a tetravalent live- attenuated dengue virus vaccine into children in

TECHNOLOGY TRANSFER ENVIRONMENTAL REGULATIONS AND TECHNOLOGY : CONTROL OF PATHOGENS IN MUNICIPAL WASTEWATER SLUDGE

EPA Science Inventory

This 71 - page Technology Transfer Environmental Regulations and echnology publication describes the Federal requirements promulgated in 1979 for reducing pathogens n wastewater sludge and provides guidance in determining whether individual sludge treatment andated or particular ...

High-pressure processing and antimicrobial biodegradable packaging to control Listeria monocytogenes during storage of cooked ham.

PubMed

Marcos, Begonya; Aymerich, Teresa; Monfort, Josep M; Garriga, Margarita

2008-02-01

The efficiency of combining high-pressure processing (HPP) and active packaging technologies to control Listeria monocytogenes growth during the shelf life of artificially inoculated cooked ham was assessed. Three lots of cooked ham were prepared: control, packaging with alginate films, and packaging with antimicrobial alginate films containing enterocins. After packaging, half of the samples were pressurized. Sliced cooked ham stored at 6 degrees C experienced a quick growth of L. monocytogenes. Both antimicrobial packaging and pressurization delayed the growth of the pathogen. However, at 6 degrees C the combination of antimicrobial packaging and HPP was necessary to achieve a reduction of inoculated levels without recovery during 60 days of storage. Further storage at 6 degrees C of pressurized antimicrobial packed cooked ham resulted in L. monocytogenes levels below the detection limit (day 90). On the other hand, storage at 1 degrees C controlled the growth of the pathogen until day 39 in non-pressurized ham, while antimicrobial packaging and storage at 1 degrees C exerted a bacteriostatic effect for 60 days. All HPP lots stored at 1 degrees C led to counts <100CFU/g at day 60. Similar results were observed when combining both technologies. After a cold chain break no growth of L. monocytogenes was observed in pressurized ham packed with antimicrobial films, showing the efficiency of combining both technologies.

Risk-based enteric pathogen reduction targets for non-potable and direct potable use of roof runoff, stormwater, and greywater

EPA Science Inventory

This paper presents risk-based enteric pathogen log reduction targets for non-potable and potable uses of a variety of alternative source waters (i.e., locally-collected greywater, roof runoff, and stormwater). A probabilistic Quantitative Microbial Risk Assessment (QMRA) was use...

Dual-mode acoustic wave biosensors microarrays

NASA Astrophysics Data System (ADS)

Auner, Gregory W.; Shreve, Gina; Ying, Hao; Newaz, Golam; Hughes, Chantelle; Xu, Jianzeng

2003-04-01

We have develop highly sensitive and selective acoustic wave biosensor arrays with signal analysis systems to provide a fingerprint for the real-time identification and quantification of a wide array of bacterial pathogens and environmental health hazards. We have developed an unique highly sensitive dual mode acoustic wave platform prototype that, when combined with phage based selective detection elements, form a durable bacteria sensor. Arrays of these new real-time biosensors are integrated to form a biosensor array on a chip. This research and development program optimizes advanced piezoelectric aluminum nitride wide bandgap semiconductors, novel micromachining processes, advanced device structures, selective phage displays development and immobilization techniques, and system integration and signal analysis technology to develop the biosensor arrays. The dual sensor platform can be programmed to sense in a gas, vapor or liquid environment by switching between acoustic wave resonate modes. Such a dual mode sensor has tremendous implications for applications involving monitoring of pathogenic microorganisms in the clinical setting due to their ability to detect airborne pathogens. This provides a number of applications including hospital settings such as intensive care or other in-patient wards for the reduction of nosocomial infections and maintenance of sterile environments in surgical suites. Monitoring for airborn pathogen transmission in public transportation areas such as airplanes may be useful for implementation of strategies for redution of airborn transmission routes. The ability to use the same sensor in the liquid sensing mode is important for tracing the source of airborn pathogens to local liquid sources. Sensing of pathogens in saliva will be useful for sensing oral pathogens and support of decision-making strategies regarding prevention of transmission and support of treatment strategies.

Modelling pathogen log10 reduction values achieved by activated sludge treatment using naïve and semi naïve Bayes network models.

PubMed

Carvajal, Guido; Roser, David J; Sisson, Scott A; Keegan, Alexandra; Khan, Stuart J

2015-11-15

Risk management for wastewater treatment and reuse have led to growing interest in understanding and optimising pathogen reduction during biological treatment processes. However, modelling pathogen reduction is often limited by poor characterization of the relationships between variables and incomplete knowledge of removal mechanisms. The aim of this paper was to assess the applicability of Bayesian belief network models to represent associations between pathogen reduction, and operating conditions and monitoring parameters and predict AS performance. Naïve Bayes and semi-naïve Bayes networks were constructed from an activated sludge dataset including operating and monitoring parameters, and removal efficiencies for two pathogens (native Giardia lamblia and seeded Cryptosporidium parvum) and five native microbial indicators (F-RNA bacteriophage, Clostridium perfringens, Escherichia coli, coliforms and enterococci). First we defined the Bayesian network structures for the two pathogen log10 reduction values (LRVs) class nodes discretized into two states (< and ≥ 1 LRV) using two different learning algorithms. Eight metrics, such as Prediction Accuracy (PA) and Area Under the receiver operating Curve (AUC), provided a comparison of model prediction performance, certainty and goodness of fit. This comparison was used to select the optimum models. The optimum Tree Augmented naïve models predicted removal efficiency with high AUC when all system parameters were used simultaneously (AUCs for C. parvum and G. lamblia LRVs of 0.95 and 0.87 respectively). However, metrics for individual system parameters showed only the C. parvum model was reliable. By contrast individual parameters for G. lamblia LRV prediction typically obtained low AUC scores (AUC < 0.81). Useful predictors for C. parvum LRV included solids retention time, turbidity and total coliform LRV. The methodology developed appears applicable for predicting pathogen removal efficiency in water treatment systems generally. Copyright © 2015 Elsevier Ltd. All rights reserved.

Pathogen inactivation in liquid dairy manure during anaerobic and aerobic digestions

NASA Astrophysics Data System (ADS)

Biswas, S.; Pandey, P.; Castillo, A. R.; Vaddella, V. K.

2014-12-01

Controlling manure-borne pathogens such as E. coli O157:H7, Salmonella spp. and Listeria monocytogenes are crucial for protecting surface and ground water as well as mitigating risks to human health. In California dairy farms, flushing of dairy manure (mainly animal feces and urine) from freestall barns and subsequent liquid-solid manure separation is a common practice for handling animal waste. The liquid manure fraction is generally pumped into the settling ponds and it goes into aerobic and/or anaerobic lagoons for extended period of time. Considering the importance of controlling pathogens in animal waste, the objective of the study was to understand the effects of anaerobic and aerobic digestions on the survival of three human pathogens in animal waste. The pathogen inactivation was assessed at four temperatures (30, 35, 42, and 50 °C), and the relationships between temperature and pathogen decay were estimated. Results showed a steady decrease of E. coli levels in aerobic and anaerobic digestion processes over the time; however, the decay rates varied with pathogens. The effect of temperature on Salmonella spp. and Listeria monocytogenes survival was different than the E. coli survival. In thermophilic temperatures (42 and 50 °C), decay rate was considerable greater compared to the mesophilic temperatures (30 and 35°C). The E. coli log reductions at 50 °C were 2.1 in both aerobic and anaerobic digestions after 13 days of incubation. The Salmonella spp. log reductions at 50 °C were 5.5 in aerobic digestion, and 5.9 in anaerobic digestion. The Listeria monocytogenes log reductions at 50 °C were 5.0 in aerobic digestion, and 5.6 in anaerobic digestion. The log reduction of E. coli, Salmonella spp., and Listeria monocytogens at 30 °C in aerobic environment were 0.1, 4.7, and 5.6, respectively. In anaerobic environment, the corresponding reductions were 0.4, 4.3, and 5.6, respectively. We anticipate that the outcomes of the study will help improving the existing animal waste management processes to control manure-borne pathogens.

Pathogen Inactivating Properties and Increased Sensitivity in Molecular Diagnostics by PAXgene, a Novel Non-Crosslinking Tissue Fixative.

PubMed

Loibner, Martina; Buzina, Walter; Viertler, Christian; Groelz, Daniel; Hausleitner, Anja; Siaulyte, Gintare; Kufferath, Iris; Kölli, Bettina; Zatloukal, Kurt

2016-01-01

Requirements on tissue fixatives are getting more demanding as molecular analysis becomes increasingly relevant for routine diagnostics. Buffered formaldehyde in pathology laboratories for tissue fixation is known to cause chemical modifications of biomolecules which affect molecular testing. A novel non-crosslinking tissue preservation technology, PAXgene Tissue (PAXgene), was developed to preserve the integrity of nucleic acids in a comparable way to cryopreservation and also to preserve morphological features comparable to those of formalin fixed samples. Because of the excellent preservation of biomolecules by PAXgene we investigated its pathogen inactivation ability and biosafety in comparison to formalin by in-vitro testing of bacteria, human relevant fungi and human cytomegalovirus (CMV). Guidelines for testing disinfectants served as reference for inactivation assays. Furthermore, we tested the properties of PAXgene for detection of pathogens by PCR based assays. All microorganisms tested were similarly inactivated by PAXgene and formalin except Clostridium sporogenes, which remained viable in seven out of ten assays after PAXgene treatment and in three out of ten assays after formalin fixation. The findings suggest that similar biosafety measures can be applied for PAXgene and formalin fixed samples. Detection of pathogens in PCR-based diagnostics using two CMV assays resulted in a reduction of four to ten quantification cycles of PAXgene treated samples which is a remarkable increase of sensitivity. PAXgene fixation might be superior to formalin fixation when molecular diagnostics and highly sensitive detection of pathogens is required in parallel to morphology assessment.

The use of visible light and metal oxide nano particles for pathogen inactivation

NASA Astrophysics Data System (ADS)

Lubart, R.; Lipovski, A.; Gedanken, A.

2012-09-01

Since the effectiveness of antibiotic treatment is decreasing due to the development of resistant strains, alternative approaches for destroying microorganisms are needed. In this review we summarize new technologies that might be effective for pathogen inactivation. In the past we found that intense blue light could be used for bacterial eradication. The phototoxic effect correlated with the amount of reactive oxygen species (ROS) generated by the bacteria due to illumination. Recently it has been shown that the effect of light can be enhanced by introducing metal oxide nanoparticles (nps) to the bacteria prior to irradiation. This led us to suggest combining nanoparticles with visible light irradiation for pathogen eradication. We have shown that combination of illumination with the nanoparticles (ZnO or TiO2) resulted in a marked increase in the reduction of bacterial viability to a mean reduction of 80-90% for both nanoaprticles. As a matter of fact metal oxide nps alone can be used for bacteria destruction. The advantage of our approach is the use of lower concentrations of nps, combined with reduced light intensity that is less toxic to the host tissue. To further avoid the toxicity of metal oxides nps on healthy tissue it is possible to coat their surfaces with various substrates including ceramics and polymers. Recently Zinc oxide nanoparticles have been synthesized and deposited on the surface of cotton fabrics using ultrasound irradiation. Thus in the future we will try to treat infected wounds with transparent bandages coated with ZnO that will be applied to the wounds prior to irradiation.

Inactivation of Mycobacterium bovis ssp. caprae in high-temperature, short-term pasteurized pilot-plant milk.

PubMed

Hammer, P; Richter, E; Rüsch-Gerdes, S; Walte, H-G C; Matzen, S; Kiesner, C

2015-03-01

Experiments to determine the efficacy of high temperature, short time (HTST) pasteurization of milk in terms of inactivation of pathogenic microorganisms were mainly performed between 1930 and 1960. Among the target organisms were Mycobacterium bovis and Mycobacterium tuberculosis. As a result, the Codex Alimentarius prescribes that HTST treatment of milk should lead to a significant reduction of pathogenic microorganisms during milk pasteurization. Due to the development of improved methods for the detection of survivors and of more advanced heating technology, verification of this requirement seemed to be necessary. To address recent outbreaks of tuberculosis in cattle caused by M. bovis ssp. caprae (M. caprae) in the southern regions of Germany, this organism was tested and compared with M. bovis ssp. bovis (M. bovis). Experiments were performed in a pilot plant for HTST pasteurization of milk with 3 strains of M. caprae and 1 strain of M. bovis. In preliminary trials at a fixed holding time of 25 s, the temperature at which significant inactivation occurred was 62.5°C for all strains. To determine D-values (decimal reduction times) for the inactivation kinetics, the strains were tested at 65, 62.5, and 60°C at holding times of 16.5, 25, and 35 s. At 65°C, the D-values of all strains ranged from 6.8 to 7.8 s, and at 62.5°C, D-values ranged from 14.5 to 18.1 s. Low inactivation was observed at 60°C. When the low slope of the inactivation curve allowed calculation of a D-value, these ranged from 40.8 to 129.9 s. In terms of log10 reductions, the highest values for all strains were 4.1 to 4.9 log at 65°C, with a holding time of 35 s. The tested strains of M. caprae and M. bovis showed similar low resistance to heat. Standard HTST treatment should result in a high reduction of these organisms and thus the requirements of the Codex Alimentarius for inactivation of pathogens by this process are far exceeded. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Molecular-based surveillance of campylobacteriosis in New Zealand--from source attribution to genomic epidemiology.

PubMed

Muellner, P; Pleydell, E; Pirie, R; Baker, M G; Campbell, D; Carter, P E; French, N P

2013-01-17

Molecular-based surveillance of campylobacteriosis in New Zealand contributed to the implementation of interventions that led to a 50% reduction in notified and hospitalised cases of the country's most important zoonosis. From a pre-intervention high of 384 per 100,000 population in 2006, incidence dropped by 50% in 2008; a reduction that has been sustained since. This article illustrates many aspects of the successful use of molecular-based surveillance, including the distinction between control-focused and strategy-focused surveillance and advances in source attribution. We discuss how microbial genetic data can enhance the understanding of epidemiological explanatory and response variables and thereby enrich the epidemiological analysis. Sequence data can be fitted to evolutionary and epidemiological models to gain new insights into pathogen evolution, the nature of associations between strains of pathogens and host species, and aspects of between-host transmission. With the advent of newer sequencing technologies and the availability of rapid, high-coverage genome sequence data, such techniques may be extended and refined within the emerging discipline of genomic epidemiology. The aim of this article is to summarise the experience gained in New Zealand with molecular-based surveillance of campylobacteriosis and to discuss how this experience could be used to further advance the use of molecular tools in surveillance.

TREATMENT OF MUNICIPAL SLUDGE FOR PATHOGEN REDUCTION

EPA Science Inventory

This presentation reviews the pathogenic microorganisms that may be found in municipal sewage sludge and the commonly employed Class A and B processes for controlling pathogens. It notes how extensively they are used and discusses issues and concerns with their application. The...

The effect of tar spot pathogen on host plant carbon balance and its possible consequences on a tundra ecosystem.

PubMed

Masumoto, Shota; Uchida, Masaki; Tojo, Motoaki; Herrero, Maria Luz; Mori, Akira S; Imura, Satoshi

2018-03-01

In Arctic tundra, plant pathogens have substantial effects on the growth and survival of hosts, and impacts on the carbon balance at the scale of ecological systems. To understand these effects on carbon dynamics across different scales including plant organ, individual, population and ecosystem, we focused on two primary factors: host productivity reduction and carbon consumption by the pathogen. We measured the effect of the pathogen on photosynthetic and respiratory activity in the host. We also measured respiration and the amount of carbon in the pathogen. We constructed a model based on these two factors, and calculated pathogenic effects on the carbon balance at different organismal and ecological scales. We found that carbon was reduced in infected leaves by 118% compared with healthy leaves; the major factor causing this loss was pathogenic carbon consumption. The carbon balance at the population and ecosystem levels decreased by 35% and 20%, respectively, at an infection rate of 30%. This case study provides the first evidence that a host plant can lose more carbon through pathogenic carbon consumption than through a reduction in productivity. Such a pathogenic effect could greatly change ecosystem carbon cycling without decreasing annual productivity.

Deactivation of Legionella Pneumophila in municipal wastewater by ozone generated in arrays of microchannel plasmas

NASA Astrophysics Data System (ADS)

Dong, Shengkun; Li, Jun; Kim, Min-Hwan; Cho, Jinhoon; Park, Sung-Jin; Nguyen, Thanh H.; Eden, J. Gary

2018-06-01

A greater than four log10 reduction in the concentration of Legionella pneumophila in municipal wastewater has been achieved in 1 min with ozone produced by a microchannel plasma reactor. Requiring less than 22 W of electrical power, and ambient air as the feedstock gas, the microplasma ozone generator is robust and a promising alternative to conventional corona and dielectric barrier discharge (DBD) technologies. Contrary to previous studies, the Ct model for pathogen deactivation (i.e. rate proportional to the product of the available disinfectant concentration and the exposure duration) is found to be valid for L. pneumophila. Accordingly, wastewater-specific Ct equations have been developed to predict the deactivation of L. pneumophila in the secondary wastewater environment. Inactivation of this pathogen was found to be dependent on temperature only in the absence of wastewater organic matter (WOM). In the presence of WOM, pathogen deactivation is controlled by the disinfection contact time, initial ozone concentration (varied between 15 and 281 µg l‑1), and initial WOM loading. The data reported here will assist in the implementation of plasma ozone generators for L. pneumophila deactivation in cooling towers, point-of-use systems, and wastewater reclamation facilities.

The combined effect of platelet storage media and intercept pathogen reduction technology on platelet activation/activability and cellular apoptosis/necrosis: Lisbon-RBS experience.

PubMed

Carvalho, Helena; Alguero, Carmen; Santos, Matilde; de Sousa, Gracinda; Trindade, Helder; Seghatchian, Jerard

2006-04-01

Platelets are known to undergo shape change, activation, a release reaction and apoptosis/necrosis during processing and storage, all of which are collectively known as the platelet storage lesion. Any additional processing may have some deleterious impact on platelet activability and functional integrity, which need to be investigated. This preliminary investigation was undertaken to establish the combined effects of standard platelet storage media and the intercept pathogen reduction technology on platelet activation and activability during 7 day storage, using buffy-coat derived platelets in standard storage media containing 35% plasma (N=24). P-selectin (CD62p) expression, a classical marker of platelet activation, and phosphatidylserine (PS) exposure on the platelet surface membrane, a hallmark of cellular necrosis/apoptosis, were both measured by flow cytometry. The results reveal significant increases in activation, from an average of 22.7% on day 1 before treatment to 31.6% on day 2 after treatment and 58.7% at the end of storage. Concomitantly, the basal expression of PS was slightly increased from 1.9% to 2.8% at day 2 after treatment and 7.3% at the end of storage. However, the functional reserve of platelets during storage, which reflects their capability to undergo activation and the release reaction when platelets were challenged with either calcium ionophore or thrombin, was relatively well maintained. These preliminary data confirm the earlier data on the use of intercept, and for the first time, based on the assessment of platelet functional integrity, suggest that platelet functional reserve is relatively well maintained, with little change in the formation of apoptotic cells.

Whole-leaf wash improves chlorine efficacy for microbial reduction and prevents pathogen cross-contamination during fresh-cut lettuce processing.

PubMed

Nou, Xiangwu; Luo, Yaguang

2010-06-01

Currently, most fresh-cut processing facilities in the United States use chlorinated water or other sanitizer solutions for microbial reduction after lettuce is cut. Freshly cut lettuce releases significant amounts of organic matter that negatively impacts the effectiveness of chlorine or other sanitizers for microbial reduction. The objective of this study is to evaluate whether a sanitizer wash before cutting improves microbial reduction efficacy compared to a traditional postcutting sanitizer wash. Romaine lettuce leaves were quantitatively inoculated with E. coli O157:H7 strains and washed in chlorinated water before or after cutting, and E. coli O157:H7 cells that survived the washing process were enumerated to determine the effectiveness of microbial reduction for the 2 cutting and washing sequences. Whole-leaf washing in chlorinated water improved pathogen reduction by approximately 1 log unit over traditional cut-leaf sanitization. Similar improvement in the reduction of background microflora was also observed. Inoculated "Lollo Rossa" red lettuce leaves were mixed with noninoculated Green-Leaf lettuce leaves to evaluate pathogen cross-contamination during processing. High level (96.7% subsamples, average MPN 0.6 log CFU/g) of cross-contamination of noninoculated green leaves by inoculated red leaves was observed when mixed lettuce leaves were cut prior to washing in chlorinated water. In contrast, cross-contamination of noninoculated green leaves was significantly reduced (3.3% of subsamples, average MPN

Inactivation of selected bacterial pathogens in dairy cattle manure by mesophilic anaerobic digestion (balloon type digester).

PubMed

Manyi-Loh, Christy E; Mamphweli, Sampson N; Meyer, Edson L; Okoh, Anthony I; Makaka, Golden; Simon, Michael

2014-07-14

Anaerobic digestion of animal manure in biogas digesters has shown promise as a technology in reducing the microbial load to safe and recommended levels. We sought to treat dairy manure obtained from the Fort Hare Dairy Farm by investigating the survival rates of bacterial pathogens, through a total viable plate count method, before, during and after mesophilic anaerobic digestion. Different microbiological media were inoculated with different serial dilutions of manure samples that were withdrawn from the biogas digester at 3, 7 and 14 day intervals to determine the viable cells. Data obtained indicated that the pathogens of public health importance were 90%-99% reduced in the order: Campylobacter sp. (18 days) < Escherichia coli sp. (62 days) < Salmonella sp. (133 days) from a viable count of 10.1 × 103, 3.6 × 105, 7.4 × 103 to concentrations below the detection limit (DL = 102 cfu/g manure), respectively. This disparity in survival rates may be influenced by the inherent characteristics of these bacteria, available nutrients as well as the stages of the anaerobic digestion process. In addition, the highest p-value i.e., 0.957 for E. coli showed the statistical significance of its model and the strongest correlation between its reductions with days of digestion. In conclusion, the results demonstrated that the specific bacterial pathogens in manure can be considerably reduced through anaerobic digestion after 133 days.

High-throughput sequencing in veterinary infection biology and diagnostics.

PubMed

Belák, S; Karlsson, O E; Leijon, M; Granberg, F

2013-12-01

Sequencing methods have improved rapidly since the first versions of the Sanger techniques, facilitating the development of very powerful tools for detecting and identifying various pathogens, such as viruses, bacteria and other microbes. The ongoing development of high-throughput sequencing (HTS; also known as next-generation sequencing) technologies has resulted in a dramatic reduction in DNA sequencing costs, making the technology more accessible to the average laboratory. In this White Paper of the World Organisation for Animal Health (OIE) Collaborating Centre for the Biotechnology-based Diagnosis of Infectious Diseases in Veterinary Medicine (Uppsala, Sweden), several approaches and examples of HTS are summarised, and their diagnostic applicability is briefly discussed. Selected future aspects of HTS are outlined, including the need for bioinformatic resources, with a focus on improving the diagnosis and control of infectious diseases in veterinary medicine.

Comparison of eggshell surface sanitization technologies and impacts on consumer acceptability.

PubMed

Al-Ajeeli, Morouj N; Taylor, T Matthew; Alvarado, Christine Z; Coufal, Craig D

2016-05-01

Shell eggs can be contaminated with many types of microorganisms, including bacterial pathogens, and thus present a risk for the transmission of foodborne disease to consumers. Currently, most United States egg processors utilize egg washing and sanitization systems to decontaminate surfaces of shell eggs prior to packaging. However, previous research has indicated that current shell egg sanitization technologies employed in the commercial egg industry may not completely eliminate bacteria from the surface of eggshells, and thus alternative egg sanitization technologies with the potential for increased microbial reductions on eggshells should be investigated. The objectives of this study were to compare the antimicrobial efficacy and consumer sensory attributes of industry-available eggshell sanitization methods (chlorine and quaternary ammonium compounds (QAC) applied via spray) to various alternative egg sanitization technologies. Eggs (White Leghorn hens; n=195) were obtained for evaluation of sanitizer-induced reduction in mesophilic aerobic bacteria (n=90) or inoculated Salmonella Enteritidis (SE) reduction (n=105). Sanitizing treatments evaluated in this experiment were: chlorine spray (100 ppm available chlorine), QAC spray (200 ppm), peracetic acid spray (PAA; 135 ppm) alone or in combination with ultraviolet light (UV; 254 nm), and hydrogen peroxide (H2O2; 3.5% solution) spray in combination with UV (H2O2+UV). For enumeration of aerobic bacteria, eggs were sampled at 0, 7, and 14 days of storage at 4°C; surviving SE cells from inoculated eggs were enumerated by differential plating. Sensory trials were conducted to determine consumer liking of scrambled eggs made from eggs sanitized with chlorine, QAC, H2O2+UV, or no treatment (control). The H2O2 and UV treatment resulted in the greatest reductions in eggshell aerobic plate counts compared to other treatments throughout egg storage (P<0.05). All treatments utilized reduced SE below the limit of detection by eggshell rinse. There were no differences in consumers' liking of overall flavor between the 4 treatments evaluated. The application of H2O2+UV treatment to shell eggs represents a novel technology that could have important implications for egg quality and safety preservation. © 2016 Poultry Science Association Inc.

Pathogen reduction of blood components.

PubMed

Solheim, Bjarte G

2008-08-01

Thanks to many blood safety interventions introduced in developed countries the risk of transfusion transmitted infections has become exceedingly small in these countries. However, emerging pathogens still represent a serious challenge, as demonstrated by West Nile virus in the US and more recently by Chikungunya virus in the Indian Ocean. In addition bacterial contamination, particularly in platelets, and protozoa transmitted by blood components still represent sizeable risks in developed countries. In developing countries the risk of all transfusion transmitted infections is still high due to insufficient funding and organisation of the health service. Pathogen reduction of pooled plasma products has virtually eliminated the risk of transfusion transmitted infections, without compromising the quality of the products significantly. Pathogen reduction of blood components has been much more challenging. Solvent detergent treatment which has been so successfully applied for plasma products dissolves cell membranes, and can, therefore, only be applied for plasma and not for cellular blood components. Targeting of nucleic acids has been another method for pathogen inactivation of plasma and the only approach possible for cellular blood products. As documented in more than 15 year's track record, solvent detergent treatment of pooled plasma can yield high quality plasma. The increased risk for contamination by unknown viruses due to pooling is out weighed by elimination of TRALI, significant reduction in allergic reactions and standardisation of the product. Recently, a promising method for solvent detergent treatment of single donor plasma units has been published. Methylene blue light treatment of single donor plasma units has a similar long track record as pooled solvent detergent treated plasma; but the method is less well documented and affects coagulation factor activity more. Psoralen light treated plasma has only recently been introduced (CE marked in Europe, but not licensed by the FDA), while the method of Riboflavin light treatment of plasma still is under development. In addition to pathogen reduction the methods, however, result in some reduction of coagulation factor activity. For platelets only Psoralen and Riboflavin light treatment have been implemented. Both are CE marked products in Europe but only approved for clinical trials in the USA. The methods affect platelet activity, but result in clinically acceptable platelets with only slightly reduced CCI and increased demand for platelet transfusions. Pathogen reduction of red blood cells with FRALE (S-303) or INACTINE (PEN110) has so far resulted in the formation of antibodies against neo-epitopes on red blood cells. A promising method for Riboflavin treatment of red blood cells is under development. This manuscript reviews the current experience and discusses future trends.

Rapid, non-invasive imaging of alphaviral brain infection: reducing animal numbers and morbidity to identify efficacy of potential vaccines and antivirals.

PubMed

Patterson, Michael; Poussard, Allison; Taylor, Katherine; Seregin, Alexey; Smith, Jeanon; Peng, Bi-Hung; Walker, Aida; Linde, Jenna; Smith, Jennifer; Salazar, Milagros; Paessler, Slobodan

2011-11-21

Rapid and accurate identification of disease progression are key factors in testing novel vaccines and antivirals against encephalitic alphaviruses. Typical efficacy studies utilize a large number of animals and severe morbidity or mortality as an endpoint. New technologies provide a means to reduce and refine the animal use as proposed in Hume's 3Rs (replacement, reduction, refinement) described by Russel and Burch. In vivo imaging systems (IVIS) and bioluminescent enzyme technologies accomplish the reduction of animal requirements while shortening the experimental time and improving the accuracy in localizing active virus replication. In the case of murine models of viral encephalitis in which central nervous system (CNS) viral invasion occurs rapidly but the disease development is relatively slow, we visualized the initial brain infection and enhance the data collection process required for efficacy studies on antivirals or vaccines that are aimed at preventing brain infection. Accordingly, we infected mice through intranasal inoculation with the genetically modified pathogen, Venezuelan equine encephalitis, which expresses a luciferase gene. In this study, we were able to identify the invasion of the CNS at least 3 days before any clinical signs of disease, allowing for reduction of animal morbidity providing a humane means of disease and vaccine research while obtaining scientific data accurately and more rapidly. Based on our data from the imaging model, we confirmed the usefulness of this technology in preclinical research by demonstrating the efficacy of Ampligen, a TLR-3 agonist, in preventing CNS invasion. Copyright © 2011 Elsevier Ltd. All rights reserved.

Airborne Pathogens inside Automobiles for Domestic Use: Assessing In-Car Air Decontamination Devices Using Staphylococcus aureus as the Challenge Bacterium.

PubMed

Sattar, Syed A; Zargar, Bahram; Wright, Kathryn E; Rubino, Joseph R; Ijaz, M Khalid

2017-05-15

Family cars represent ∼74% of the yearly global output of motorized vehicles. With a life expectancy of ∼8 decades in many countries, the average person spends >100 min daily inside the confined and often shared space of the car, with exposure to a mix of potentially harmful microbes. Can commercial in-car microbial air decontamination devices mitigate the risk? Three such devices (designated devices 1 to 3) with HEPA filters were tested in the modified passenger cabin (3.25 m 3 ) of a four-door sedan housed within a biosafety level 3 containment facility. Staphylococcus aureus (ATCC 6538) was suspended in a soil load to simulate the presence of body fluids and aerosolized into the car's cabin with a 6-jet Collison nebulizer. A muffin fan (80 mm by 80 mm, with an output of 0.17 m 3 /min) circulated the air inside. Plates (150 mm diameter) of Trypticase soy agar (TSA), placed inside a programmable slit-to-agar sampler, were held at 36 ± 1°C for 18 to 24 h and examined for CFU. The input dose of the test bacterium, its rate of biological decay, and the log 10 reductions by the test devices were analyzed. The arbitrarily set performance criterion was the time in hours a device took for a 3-log 10 reduction in the level of airborne challenge bacterium. On average, the level of S. aureus challenge in the air varied between 4.2 log 10 CFU/m 3 and 5.5 log 10 CFU/m 3 , and its rate of biological decay was -0.0213 ± 0.0021 log 10 CFU/m 3 /min. Devices 1 to 3 took 2.3, 1.5, and 9.7 h, respectively, to meet the performance criterion. While the experimental setup was tested using S. aureus as an archetypical airborne pathogen, it can be readily adapted to test other types of pathogens and technologies. IMPORTANCE This study was designed to test the survival of airborne pathogens in the confined and shared space of a family automobile as well as to assess claims of devices marketed for in-car air decontamination. The basic experimental setup and the test protocols reported are versatile enough for work with all major types of airborne human pathogens and for testing a wide variety of air decontamination technologies. This study could also lay the foundation for a standardized test protocol for use by device makers as well as regulators for the registration of such devices. Copyright © 2017 American Society for Microbiology.

Airborne Pathogens inside Automobiles for Domestic Use: Assessing In-Car Air Decontamination Devices Using Staphylococcus aureus as the Challenge Bacterium

PubMed Central

Zargar, Bahram; Wright, Kathryn E.; Rubino, Joseph R.; Ijaz, M. Khalid

2017-01-01

ABSTRACT Family cars represent ∼74% of the yearly global output of motorized vehicles. With a life expectancy of ∼8 decades in many countries, the average person spends >100 min daily inside the confined and often shared space of the car, with exposure to a mix of potentially harmful microbes. Can commercial in-car microbial air decontamination devices mitigate the risk? Three such devices (designated devices 1 to 3) with HEPA filters were tested in the modified passenger cabin (3.25 m3) of a four-door sedan housed within a biosafety level 3 containment facility. Staphylococcus aureus (ATCC 6538) was suspended in a soil load to simulate the presence of body fluids and aerosolized into the car's cabin with a 6-jet Collison nebulizer. A muffin fan (80 mm by 80 mm, with an output of 0.17 m3/min) circulated the air inside. Plates (150 mm diameter) of Trypticase soy agar (TSA), placed inside a programmable slit-to-agar sampler, were held at 36 ± 1°C for 18 to 24 h and examined for CFU. The input dose of the test bacterium, its rate of biological decay, and the log10 reductions by the test devices were analyzed. The arbitrarily set performance criterion was the time in hours a device took for a 3-log10 reduction in the level of airborne challenge bacterium. On average, the level of S. aureus challenge in the air varied between 4.2 log10 CFU/m3 and 5.5 log10 CFU/m3, and its rate of biological decay was −0.0213 ± 0.0021 log10 CFU/m3/min. Devices 1 to 3 took 2.3, 1.5, and 9.7 h, respectively, to meet the performance criterion. While the experimental setup was tested using S. aureus as an archetypical airborne pathogen, it can be readily adapted to test other types of pathogens and technologies. IMPORTANCE This study was designed to test the survival of airborne pathogens in the confined and shared space of a family automobile as well as to assess claims of devices marketed for in-car air decontamination. The basic experimental setup and the test protocols reported are versatile enough for work with all major types of airborne human pathogens and for testing a wide variety of air decontamination technologies. This study could also lay the foundation for a standardized test protocol for use by device makers as well as regulators for the registration of such devices. PMID:28389537

Recovery opportunities for metals and energy from sewage sludges.

PubMed

Mulchandani, Anjali; Westerhoff, Paul

2016-09-01

Limitations on current wastewater treatment plant (WWTP) biological processes and solids disposal options present opportunities to implement novel technologies that convert WWTPs into resource recovery facilities. This review considered replacing or augmenting extensive dewatering, anaerobic digestion, and off-site disposal with new thermo-chemical and liquid extraction processes. These technologies may better recover energy and metals while inactivating pathogens and destroying organic pollutants. Because limited direct comparisons between different sludge types exist in the literature for hydrothermal liquefaction, this study augments the findings with experimental data. These experiments demonstrated 50% reduction in sludge mass, with 30% of liquefaction products converted to bio-oil and most metals sequestered within a small mass of solid bio-char residue. Finally, each technology's contribution to the three sustainability pillars is investigated. Although limiting hazardous materials reintroduction to the environment may increase economic cost of sludge treatment, it is balanced by cleaner environment and valuable resource benefits for society. Copyright © 2016 Elsevier Ltd. All rights reserved.

Viable-but-Nonculturable Listeria monocytogenes and Salmonella enterica Serovar Thompson Induced by Chlorine Stress Remain Infectious.

PubMed

Highmore, Callum J; Warner, Jennifer C; Rothwell, Steve D; Wilks, Sandra A; Keevil, C William

2018-04-17

The microbiological safety of fresh produce is monitored almost exclusively by culture-based detection methods. However, bacterial food-borne pathogens are known to enter a viable-but-nonculturable (VBNC) state in response to environmental stresses such as chlorine, which is commonly used for fresh produce decontamination. Here, complete VBNC induction of green fluorescent protein-tagged Listeria monocytogenes and Salmonella enterica serovar Thompson was achieved by exposure to 12 and 3 ppm chlorine, respectively. The pathogens were subjected to chlorine washing following incubation on spinach leaves. Culture data revealed that total viable L. monocytogenes and Salmonella Thompson populations became VBNC by 50 and 100 ppm chlorine, respectively, while enumeration by direct viable counting found that chlorine caused a <1-log reduction in viability. The pathogenicity of chlorine-induced VBNC L. monocytogenes and Salmonella Thompson was assessed by using Caenorhabditis elegans Ingestion of VBNC pathogens by C. elegans resulted in a significant life span reduction ( P = 0.0064 and P < 0.0001), and no significant difference between the life span reductions caused by the VBNC and culturable L. monocytogenes treatments was observed. L. monocytogenes was visualized beyond the nematode intestinal lumen, indicating resuscitation and cell invasion. These data emphasize the risk that VBNC food-borne pathogens could pose to public health should they continue to go undetected. IMPORTANCE Many bacteria are known to enter a viable-but-nonculturable (VBNC) state in response to environmental stresses. VBNC cells cannot be detected by standard laboratory culture techniques, presenting a problem for the food industry, which uses these techniques to detect pathogen contaminants. This study found that chlorine, a sanitizer commonly used for fresh produce, induces a VBNC state in the food-borne pathogens Listeria monocytogenes and Salmonella enterica It was also found that chlorine is ineffective at killing total populations of the pathogens. A life span reduction was observed in Caenorhabditis elegans that ingested these VBNC pathogens, with VBNC L. monocytogenes as infectious as its culturable counterpart. These data show that VBNC food-borne pathogens can both be generated and avoid detection by industrial practices while potentially retaining the ability to cause disease. Copyright © 2018 Highmore et al.

Methods to study legionella transcriptome in vitro and in vivo.

PubMed

Faucher, Sebastien P; Shuman, Howard A

2013-01-01

The study of transcriptome responses can provide insight into the regulatory pathways and genetic factors that contribute to a specific phenotype. For bacterial pathogens, it can identify putative new virulence systems and shed light on the mechanisms underlying the regulation of virulence factors. Microarrays have been previously used to study gene regulation in Legionella pneumophila. In the past few years a sharp reduction of the costs associated with microarray experiments together with the availability of relatively inexpensive custom-designed commercial microarrays has made microarray technology an accessible tool for the majority of researchers. Here we describe the methodologies to conduct microarray experiments from in vitro and in vivo samples.

Pathogen reduction in minimally managed composting of bovine manure

USDA-ARS?s Scientific Manuscript database

Persistence of pathogenic bacteria such as E. coli O157:H7, Salmonella spp., and Listeria monocytogenes in bovine feces and contaminated soils is an important risk factor in perpetuating the initial infection as well as re-infection of cattle and dissemination of pathogens throughout agricultural la...

FROM CONCEPT TO EQUIVALENCY: GETTING YOUR INNOVATIVE SLUDGE DISINFECTION PROCESS CLASSIFIED AS A OR B IS NOW LESS OF A MYSTERY

EPA Science Inventory

The Pathogen Equivalency Committee has updated the criteria it uses to make recommendations of equivalency on innovative or alternative sludge pathogen reduction processes. To assist new applicants through the equivalency recommendation process the pathogen equivalency committee ...

Proteome changes in platelets after pathogen inactivation--an interlaboratory consensus.

PubMed

Prudent, Michel; D'Alessandro, Angelo; Cazenave, Jean-Pierre; Devine, Dana V; Gachet, Christian; Greinacher, Andreas; Lion, Niels; Schubert, Peter; Steil, Leif; Thiele, Thomas; Tissot, Jean-Daniel; Völker, Uwe; Zolla, Lello

2014-04-01

Pathogen inactivation (PI) of platelet concentrates (PCs) reduces the proliferation/replication of a large range of bacteria, viruses, and parasites as well as residual leucocytes. Pathogen-inactivated PCs were evaluated in various clinical trials showing their efficacy and safety. Today, there is some debate over the hemostatic activity of treated PCs as the overall survival of PI platelets seems to be somewhat reduced, and in vitro measurements have identified some alterations in platelet function. Although the specific lesions resulting from PI of PCs are still not fully understood, proteomic studies have revealed potential damages at the protein level. This review merges the key findings of the proteomic analyses of PCs treated by the Mirasol Pathogen Reduction Technology, the Intercept Blood System, and the Theraflex UV-C system, respectively, and discusses the potential impact on the biological functions of platelets. The complementarities of the applied proteomic approaches allow the coverage of a wide range of proteins and provide a comprehensive overview of PI-mediated protein damage. It emerges that there is a relatively weak impact of PI on the overall proteome of platelets. However, some data show that the different PI treatments lead to an acceleration of platelet storage lesions, which is in agreement with the current model of platelet storage lesion in pathogen-inactivated PCs. Overall, the impact of the PI treatment on the proteome appears to be different among the PI systems. Mirasol impacts adhesion and platelet shape change, whereas Intercept seems to impact proteins of intracellular platelet activation pathways. Theraflex influences platelet shape change and aggregation, but the data reported to date are limited. This information provides the basis to understand the impact of different PI on the molecular mechanisms of platelet function. Moreover, these data may serve as basis for future developments of PI technologies for PCs. Further studies should address the impact of both the PI and the storage duration on platelets in PCs because PI may enable the extension of the shelf life of PCs by reducing the bacterial contamination risk. Copyright © 2014 Elsevier Inc. All rights reserved.

Salt reduction in vegetable fermentation: reality or desire?

PubMed

Bautista-Gallego, J; Rantsiou, K; Garrido-Fernández, A; Cocolin, L; Arroyo-López, F N

2013-08-01

NaCl is a widely used chemical in food processing which affects sensory characteristics and safety; in fact, its presence is frequently essential for the proper preservation of the products. Because the intake of high contents of sodium is linked to adverse effects on human health, consumers demand foods with low-sodium content. A 1st step to reduce the use of salt would imply the proper application of this compound, reducing its levels to those technologically necessary. In addition, different chloride salts have been evaluated as replacers for NaCl, but KCl, CaCl2 , and ZnCl2 show the most promising perspectives of use. However, prior to any food reformulation, there is a need for exhaustive research before its application at industrial level. Salt reduction may lead to an increased risk in the survival/ growth of pathogens and may also alter food flavor and cause economic losses. This review deals with the technological, microbiological, sensorial, and health aspects of the potential low-salt and salt-substituted vegetable products and how this important segment of the food industry is responding to consumer demand. © 2013 Institute of Food Technologists®

Microbial colonization of irradiated pathogenic yeast to catheter surfaces: Relationship between adherence, cell surface hydrophobicity, biofilm formation and antifungal susceptibility. A scanning electron microscope analysis.

PubMed

Farrag, Hala Abdallah; A-Karam El-Din, Alzahraa; Mohamed El-Sayed, Zeinab Galal; Abdel-Latifissa, Soheir; Kamal, Mona Mohamed

2015-06-01

Technological advances such as long-term indwelling catheters have created milieu in which infections are a major complication. Thus it is essential to be able to recognize, diagnose, and treat infections occurring in immunocompromised patients. Adherence assay and quantitation of biofilms was performed by a spectrophotometric method, hydrophobicity was evaluated by adhesion to p-xylene. The minimum inhibitory concentration (MIC) of Nystatin was carried out by a well dilution method. Out of 100 bladder cancer patients, 23 pathogenic yeast isolates were identified. The samples were taken from urinary catheters and urine collected from their attached drainage bags. Pathogenic yeast identified were species of Candida, Cryptococcus, Saccharomyces, Blastoschizomyces, Trichosporn, Hansenula, Prototheca and Rhodotorula. With the exception of Rhodotorula minuta, the yeast were sensitive to the antimycotic agent (Nystatin) used before and after in vitro gamma irradiation at 24.41 Gy as measured by a disc diffusion method. All tested yeast strains were slime producers and showed positive adherence reactions. There were considerable differences in adherence measurements after irradiation. An increase in adherence measurement values (using a spectrophotometric method) after irradiation were detected in four strains whereas eight other strains showed a reduction in their adherence reaction. The cell surface hydrophobicity (CSH) was evaluated by adhesion to p-xylene. Candida tropicalis showed a hydrophobic reaction with an increase in the cell surface hydrophobicity after irradiation. Scanning electron microscopy of irradiated C. tropicalis showed marked abnormalities in cell shape and size with significant reduction in adherence ability at the MIC level of Nystatin (4 μg/ml). More basic research at the level of pathogenesis and catheter substance is needed to design novel strategies to prevent fungal adherence and to inhibit biofilm formation.

Effect of different GRAS compounds in the control of apples blue mould.

PubMed

Venditti, T; Cubaiu, L; Ladu, G; D'Hallewin, G

2013-01-01

The most important pathogen for apples is Penicillium expansum that is the causal organism of blue mould. Postharvest losses are controlled with chemical fungicides such as TBZ but a growing concern for human health and a greater awareness for environmental conservation have multiplied the studies on new ecological technologies. In the search of new environment and consumer friendly technologies that can reduce toxic residues, the use of GRAS compounds represent a valid alternative to the use of synthetic postharvest fungicides. The aims of the present work were: (1) To evaluate the effectiveness of different GRAS compounds in the control of P. expansum in artificially inoculated fruit; (2) To assess the capability of injured and treated fruit with GRAS compounds, used alone or combined, to heal the wounds in order to resist to infection. Fruit was injured with a steel rod and after 1 hour was (1) Inoculated with the pathogen and after 24 hours treated or (2) Treated and after 24 hours inoculated. Treatments were performed with the following compounds: sodium bicarbonate (SBC), boric acid (BA) and calcium chloride (CC) by using a 1% solution for all of them. After 9 or 14 days fruit lesion diameters were assessed. In the trial (1) the combined treatment with BA and SBC was the most effective reducing the lesion diameter by 86.5% with respect to untreated fruit, after 9 days from infection. A good pathogen control was also obtained with BA used alone or combined with CC. When the treatment was performed before infection the best results were achieved with the combination of SBC and CC, with 87% of reduction of the lesion diameter. The addition of CC also reduced the lesion if combined with BA (66.8%). These preliminary results showed that GRAS compounds can be effective in reducing blue mold by a direct effect on the pathogen, and by modulating fruit responses enhancing host resistance.

Pathogen Treatment Guidance and Monitoring Approaches fro ...

EPA Pesticide Factsheets

On-site non-potable water reuse is increasingly used to augment water supplies, but traditional fecal indicator approaches for defining and monitoring exposure risks are limited when applied to these decentralized options. This session emphasizes risk-based modeling to define pathogen log-reduction requirements coupled with alternative targets for monitoring enabled by genomic sequencing (i.e., the microbiome of reuse systems). 1. Discuss risk-based modeling to define pathogen log-reduction requirements 2. Review alternative targets for monitoring 3. Gain an understanding of how new tools can help improve successful development of sustainable on-site non-potable water reuse Presented at the Water Wastewater Equipment Treatment & Transport Show.

A transient expression assay for the in planta efficacy screening of an antimicrobial peptide against grapevine bacterial pathogens.

PubMed

Visser, M; Stephan, D; Jaynes, J M; Burger, J T

2012-06-01

Natural and synthetic antimicrobial peptides (AMPs) are of increasing interest as potential resistance conferring elements in plants against pathogen infection. The efficacy of AMPs against pathogens is prescreened by in vitro assays, and promising AMP candidates are introduced as transgenes into plants. As in vitro and in planta environments differ, a prescreening procedure of the AMP efficacy in the plant environment is desired. Here, we report the efficacy of the purified synthetic peptide D4E1 against the grapevine-infecting bacterial pathogens Agrobacterium vitis and Xylophilus ampelinus in vitro and describe for the first time an in planta prescreening procedure based on transiently expressed D4E1. The antimicrobial effect of D4E1 against Ag. vitis and X. ampelinus was shown by a reduction in colony-forming units in vitro in a traditional plate-based assay and by a reduction in bacterial titres in planta as measured by quantitative real-time PCR (qPCR) in grapevine leaves transiently expressing D4E1. A statistically significant reduction in titre was shown for X. ampelinus, but for Ag. vitis, a significant reduction in titre was only observed in a subset of plants. The titres of both grapevine-infecting bacterial pathogens were reduced in an in vitro assay and for X. ampelinus in an in planta assay by D4E1 application. This widens the applicability of D4E1 as a potential resistance-enhancing element to additional pathogens and in a novel plant species. D4E1 is a promising candidate to confer enhanced resistance against the two tested grapevine bacterial pathogens, and the applied transient expression system proved to be a valuable tool for prescreening of D4E1 efficacy in an in planta environment. The described prescreening procedure can be used for other AMPs and might be adapted to other plant species and pathogens before the expensive and tedious development of stably transgenic lines is started. © 2012 The Authors. Letters in Applied Microbiology © 2012 The Society for Applied Microbiology.

Development of a process-based model to predict pathogen budgets for the Sydney drinking water catchment.

PubMed

Ferguson, Christobel M; Croke, Barry F W; Beatson, Peter J; Ashbolt, Nicholas J; Deere, Daniel A

2007-06-01

In drinking water catchments, reduction of pathogen loads delivered to reservoirs is an important priority for the management of raw source water quality. To assist with the evaluation of management options, a process-based mathematical model (pathogen catchment budgets - PCB) is developed to predict Cryptosporidium, Giardia and E. coli loads generated within and exported from drinking water catchments. The model quantifies the key processes affecting the generation and transport of microorganisms from humans and animals using land use and flow data, and catchment specific information including point sources such as sewage treatment plants and on-site systems. The resultant pathogen catchment budgets (PCB) can be used to prioritize the implementation of control measures for the reduction of pathogen risks to drinking water. The model is applied in the Wingecarribee catchment and used to rank those sub-catchments that would contribute the highest pathogen loads in dry weather, and in intermediate and large wet weather events. A sensitivity analysis of the model identifies that pathogen excretion rates from animals and humans, and manure mobilization rates are significant factors determining the output of the model and thus warrant further investigation.

Reduction of nutrients, microbes, and personal care products in domestic wastewater by a benchtop electrocoagulation unit

PubMed Central

Symonds, E. M.; Cook, M. M.; McQuaig, S. M.; Ulrich, R. M.; Schenck, R. O.; Lukasik, J. O.; Van Vleet, E. S.; Breitbart, M.

2015-01-01

To preserve environmental and human health, improved treatment processes are needed to reduce nutrients, microbes, and emerging chemical contaminants from domestic wastewater prior to discharge into the environment. Electrocoagulation (EC) treatment is increasingly used to treat industrial wastewater; however, this technology has not yet been thoroughly assessed for its potential to reduce concentrations of nutrients, a variety of microbial surrogates, and personal care products found in domestic wastewater. This investigation's objective was to determine the efficiency of a benchtop EC unit with aluminum sacrificial electrodes to reduce concentrations of the aforementioned biological and chemical pollutants from raw and tertiary-treated domestic wastewater. EC treatment resulted in significant reductions (p < 0.05, α = 0.05) in phosphate, all microbial surrogates, and several personal care products from raw and tertiary-treated domestic wastewater. When wastewater was augmented with microbial surrogates representing bacterial, viral, and protozoan pathogens to measure the extent of reduction, EC treatment resulted in up to 7-log10 reduction of microbial surrogates. Future pilot and full-scale investigations are needed to optimize EC treatment for the following: reducing nitrogen species, personal care products, and energy consumption; elucidating the mechanisms behind microbial reductions; and performing life cycle analyses to determine the appropriateness of implementation. PMID:25797885

Reduction of nutrients, microbes, and personal care products in domestic wastewater by a benchtop electrocoagulation unit.

PubMed

Symonds, E M; Cook, M M; McQuaig, S M; Ulrich, R M; Schenck, R O; Lukasik, J O; Van Vleet, E S; Breitbart, M

2015-03-23

To preserve environmental and human health, improved treatment processes are needed to reduce nutrients, microbes, and emerging chemical contaminants from domestic wastewater prior to discharge into the environment. Electrocoagulation (EC) treatment is increasingly used to treat industrial wastewater; however, this technology has not yet been thoroughly assessed for its potential to reduce concentrations of nutrients, a variety of microbial surrogates, and personal care products found in domestic wastewater. This investigation's objective was to determine the efficiency of a benchtop EC unit with aluminum sacrificial electrodes to reduce concentrations of the aforementioned biological and chemical pollutants from raw and tertiary-treated domestic wastewater. EC treatment resulted in significant reductions (p < 0.05, α = 0.05) in phosphate, all microbial surrogates, and several personal care products from raw and tertiary-treated domestic wastewater. When wastewater was augmented with microbial surrogates representing bacterial, viral, and protozoan pathogens to measure the extent of reduction, EC treatment resulted in up to 7-log10 reduction of microbial surrogates. Future pilot and full-scale investigations are needed to optimize EC treatment for the following: reducing nitrogen species, personal care products, and energy consumption; elucidating the mechanisms behind microbial reductions; and performing life cycle analyses to determine the appropriateness of implementation.

Reduction of nutrients, microbes, and personal care products in domestic wastewater by a benchtop electrocoagulation unit

NASA Astrophysics Data System (ADS)

Symonds, E. M.; Cook, M. M.; McQuaig, S. M.; Ulrich, R. M.; Schenck, R. O.; Lukasik, J. O.; van Vleet, E. S.; Breitbart, M.

2015-03-01

To preserve environmental and human health, improved treatment processes are needed to reduce nutrients, microbes, and emerging chemical contaminants from domestic wastewater prior to discharge into the environment. Electrocoagulation (EC) treatment is increasingly used to treat industrial wastewater; however, this technology has not yet been thoroughly assessed for its potential to reduce concentrations of nutrients, a variety of microbial surrogates, and personal care products found in domestic wastewater. This investigation's objective was to determine the efficiency of a benchtop EC unit with aluminum sacrificial electrodes to reduce concentrations of the aforementioned biological and chemical pollutants from raw and tertiary-treated domestic wastewater. EC treatment resulted in significant reductions (p < 0.05, α = 0.05) in phosphate, all microbial surrogates, and several personal care products from raw and tertiary-treated domestic wastewater. When wastewater was augmented with microbial surrogates representing bacterial, viral, and protozoan pathogens to measure the extent of reduction, EC treatment resulted in up to 7-log10 reduction of microbial surrogates. Future pilot and full-scale investigations are needed to optimize EC treatment for the following: reducing nitrogen species, personal care products, and energy consumption; elucidating the mechanisms behind microbial reductions; and performing life cycle analyses to determine the appropriateness of implementation.

QPCR Analysis of Total and Viable Enterococci in Waste Water Treatment: Comparison with Culture in Predicting Pathogen Reductions

EPA Science Inventory

BEACH Act amendment to Clean Water Act requires EPA to establish more expeditious methods for the timely detection of pathogens and pathogen indicators in coastal waters New methods should demonstrate utility for and be compatible with all CWA 304(a) criteria needs including:...

Deep Sequencing in Infectious Diseases: Immune and Pathogen Repertoires for the Improvement of Patient Outcomes.

PubMed

Burkholder, William F; Newell, Evan W; Poidinger, Michael; Chen, Swaine; Fink, Katja

2017-01-01

The inaugural workshop "Deep Sequencing in Infectious Diseases: Immune and Pathogen Repertoires for the Improvement of Patient Outcomes" was held in Singapore on 13-14 October 2016. The aim of the workshop was to discuss the latest trends in using high-throughput sequencing, bioinformatics, and allied technologies to analyze immune and pathogen repertoires and their interplay within the host, bringing together key international players in the field and Singapore-based researchers and clinician-scientists. The focus was in particular on the application of these technologies for the improvement of patient diagnosis, prognosis and treatment, and for other broad public health outcomes. The presentations by scientists and clinicians showed the potential of deep sequencing technology to capture the coevolution of adaptive immunity and pathogens. For clinical applications, some key challenges remain, such as the long turnaround time and relatively high cost of deep sequencing for pathogen identification and characterization and the lack of international standardization in immune repertoire analysis.

Deep Sequencing in Infectious Diseases: Immune and Pathogen Repertoires for the Improvement of Patient Outcomes

PubMed Central

Burkholder, William F.; Newell, Evan W.; Poidinger, Michael; Chen, Swaine; Fink, Katja

2017-01-01

The inaugural workshop “Deep Sequencing in Infectious Diseases: Immune and Pathogen Repertoires for the Improvement of Patient Outcomes” was held in Singapore on 13–14 October 2016. The aim of the workshop was to discuss the latest trends in using high-throughput sequencing, bioinformatics, and allied technologies to analyze immune and pathogen repertoires and their interplay within the host, bringing together key international players in the field and Singapore-based researchers and clinician-scientists. The focus was in particular on the application of these technologies for the improvement of patient diagnosis, prognosis and treatment, and for other broad public health outcomes. The presentations by scientists and clinicians showed the potential of deep sequencing technology to capture the coevolution of adaptive immunity and pathogens. For clinical applications, some key challenges remain, such as the long turnaround time and relatively high cost of deep sequencing for pathogen identification and characterization and the lack of international standardization in immune repertoire analysis. PMID:28620372

Catheter-associated urinary tract infection.

PubMed

Tambyah, Paul A; Oon, Jolene

2012-08-01

Catheter-associated urinary tract infection (CAUTI) is the commonest nosocomial infection worldwide. Here we review the recent advances in the prevention of CAUTI. After more than 30 years, new guidelines were issued in 2008-2011 by the Infectious Diseases Society of America, Society for Healthcare Epidemiology of America, Healthcare Infection Control Practices Advisory Committee and European Association of Urology. These guidelines addressed novel technologies such as silver alloy or antimicrobial coatings on catheters, hydrophilic catheters, urethral stents, use of sealed catheter-tube junctions and antiinfective bladder irrigation. In addition, multiple trials have been published recently on the reduction of inappropriate urinary tract catheterization. Numerous strategies have been developed to reduce the incidence of CAUTI but few have proven effective. Reducing the inappropriate use of catheters and development of novel technologies targeted against these increasingly multidrug-resistant pathogens may be useful in the prevention of CAUTI in our vulnerable patients.

Thermal and non-thermal preservation techniques of tiger nuts' beverage "horchata de chufa". Implications for food safety, nutritional and quality properties.

PubMed

Roselló-Soto, Elena; Poojary, Mahesha M; Barba, Francisco J; Koubaa, Mohamed; Lorenzo, Jose M; Mañes, Jordi; Moltó, Juan Carlos

2018-03-01

"Horchata de chufa" is a traditional Spanish beverage produced from tiger nuts (Cyperus esculentus L.). Due to its richness in nutritional compounds, it is highly perishable and its conservation by pasteurization and/or adding preservatives is required. Although efficient, conventional thermal treatment for pasteurization induces changes in the nutritional and sensory properties. Replacing conventional pasteurization by non-thermal technologies such as pulsed electric fields, ultraviolet, and high pressure, combined with moderate temperatures (<40°C) allows a reduction of energy consumption, along with the preservation of the most thermo-sensitive molecules. Accordingly, this review deals with the description of the most relevant non-thermal technologies applied to preserve "horchata" beverage in order to extend the shelf life and inactivate pathogenic microorganisms as well as to preserve the nutritional and quality properties of this food beverage. Copyright © 2017 Elsevier Ltd. All rights reserved.

Bactericidal Efficiency of Silver Nanoparticles Synthesized from Annona squamosa

NASA Astrophysics Data System (ADS)

Jayavardhanan, R.; Nanda, Anima

2016-09-01

Nanotechnology is described as an emerging technology that not only holds promise for society, but also is capable of providing novel approaches to overcome our common problems. The present study focused on the synthesis of silver nanoparticles using the metabolites of Annona squamosa seeds. The biological reduction procedure proposed in this method was considered as better one compared to chemical mediated reduction methods. The advantages include nontoxic to the environment, less energy consuming and highly suitable for further biological applications. The seeds were separated from the fruit pulp, grinded into powder and dissolved in distilled water. The suspension was used as reducing agent and treated with silver nitrate at the concentration of 1mM. The reduction reaction was continuously monitored by UV-visible photo spectrometer. Further the samples were subjected to AFM, SEM and XRD analysis for the confirmation of their size, structure, agglomerations and the arrangements of crystals. Finally the antibacterial properties of nanoparticles were tested against clinically important pathogenic microorganisms using disc diffusion method and compared with the activities of standard antibiotics. The combinational effects of nanoparticles with commercial antibiotics also were tested by the same method.

Task 1.5 Genomic Shift and Drift Trends of Emerging Pathogens

DOE Office of Scientific and Technical Information (OSTI.GOV)

Borucki, M

2010-01-05

The Lawrence Livermore National Laboratory (LLNL) Bioinformatics group has recently taken on a role in DTRA's Transformation Medical Technologies Initiative (TMTI). The high-level goal of TMTI is to accelerate the development of broad-spectrum countermeasures. To achieve those goals, TMTI has a near term need to conduct analyses of genomic shift and drift trends of emerging pathogens, with a focused eye on select agent pathogens, as well as antibiotic and virulence markers. Most emerging human pathogens are zoonotic viruses with a genome composed of RNA. The high mutation rate of the replication enzymes of RNA viruses contributes to sequence drift andmore » provides one mechanism for these viruses to adapt to diverse hosts (interspecies transmission events) and cause new human and zoonotic diseases. Additionally, new viral pathogens frequently emerge due to genetic shift (recombination and segment reassortment) which allows for dramatic genotypic and phenotypic changes to occur rapidly. Bacterial pathogens also evolve via genetic drift and shift, although sequence drift generally occurs at a much slower rate for bacteria as compared to RNA viruses. However, genetic shift such as lateral gene transfer and inter- and intragenomic recombination enables bacteria to rapidly acquire new mechanisms of survival and antibiotic resistance. New technologies such as rapid whole genome sequencing of bacterial genomes, ultra-deep sequencing of RNA virus populations, metagenomic studies of environments rich in antibiotic resistance genes, and the use of microarrays for the detection and characterization of emerging pathogens provide mechanisms to address the challenges posed by the rapid emergence of pathogens. Bioinformatic algorithms that enable efficient analysis of the massive amounts of data generated by these technologies as well computational modeling of protein structures and evolutionary processes need to be developed to allow the technology to fulfill its potential.« less

A Customized DNA Microarray for Microbial Source Tracking ...

EPA Pesticide Factsheets

It is estimated that more than 160, 000 miles of rivers and streams in the United States are impaired due to the presence of waterborne pathogens. These pathogens typically originate from human and other animal fecal pollution sources; therefore, a rapid microbial source tracking (MST) method is needed to facilitate water quality assessment and impaired water remediation. We report a novel qualitative DNA microarray technology consisting of 453 probes for the detection of general fecal and host-associated bacteria, viruses, antibiotic resistance, and other environmentally relevant genetic indicators. A novel data normalization and reduction approach is also presented to help alleviate false positives often associated with high-density microarray applications. To evaluate the performance of the approach, DNA and cDNA was isolated from swine, cattle, duck, goose and gull fecal reference samples, as well as soiled poultry liter and raw municipal sewage. Based on nonmetric multidimensional scaling analysis of results, findings suggest that the novel microarray approach may be useful for pathogen detection and identification of fecal contamination in recreational waters. The ability to simultaneously detect a large collection of environmentally important genetic indicators in a single test has the potential to provide water quality managers with a wide range of information in a short period of time. Future research is warranted to measure microarray performance i

Using genomics for surveillance of veterinary infectious agents.

PubMed

Mathijs, E; Vandenbussche, F; Van Borm, S

2016-04-01

Factors such as globalisation, climate change and agricultural intensification can increase the risk of microbial emergence. As a result, there is a growing need for flexible laboratory-based surveillance tools to rapidly identify, characterise and monitor global (re-)emerging diseases. Although many tools are available, novel sequencing technologies have launched a new era in pathogen surveillance. Here, the authors review the potential applications of high-throughput genomic technologies for the surveillance of veterinary pathogens. They focus on the two types of surveillance that will benefit most from these new tools: hazard-specific surveillance (pathogen identification and typing) and early-warning surveillance (pathogen discovery). The paper reviews how the resulting sequencing data can be used to improve diagnosis and concludes by highlighting the major challenges that hinder the routine use of this technology in the veterinary field.

xMAP Technology: Applications in Detection of Pathogens

PubMed Central

Reslova, Nikol; Michna, Veronika; Kasny, Martin; Mikel, Pavel; Kralik, Petr

2017-01-01

xMAP technology is applicable for high-throughput, multiplex and simultaneous detection of different analytes within a single complex sample. xMAP multiplex assays are currently available in various nucleic acid and immunoassay formats, enabling simultaneous detection and typing of pathogenic viruses, bacteria, parasites and fungi and also antigen or antibody interception. As an open architecture platform, the xMAP technology is beneficial to end users and therefore it is used in various pharmaceutical, clinical and research laboratories. The main aim of this review is to summarize the latest findings and applications in the field of pathogen detection using microsphere-based multiplex assays. PMID:28179899

Survival of artificially inoculated Escherichia coli and Salmonella Typhimurium on the surface of raw poultry products subjected to crust freezing.

PubMed

Chaves, B D; Han, I Y; Dawson, P L; Northcutt, J K

2011-12-01

Escherichia coli and Salmonella spp. are ubiquitous in the poultry production environment, and hence, their transmission to poultry products is of concern. Industry has widely used freezing as a strategy to halt pathogen growth, and more recently, crust freezing has been suggested as a means to improve mechanical operations, quality, and safety of poultry products. The purpose of this study was to evaluate the effect of crust freezing on the survival of Escherichia coli and Salmonella Typhimurium that were artificially inoculated on the surface of raw poultry products with or without adhering skin. Ampicillin-resistant (AR) E. coli JM 109 and nalidixic acid-resistant (NAR) Salmonella Typhimurium were used in the experiments. A set of cultures was subjected to cold-shock stress by storage at 4°C for 10 d. After being either cold-shocked or non-cold-shocked, commercial chicken breasts without skin and chicken thighs with skin were inoculated in separate experiments with each bacterium. Samples were crust frozen at -85°C for 20 min or completely frozen at -85°C for 60 min. The E. coli and Salmonella Typhimurium were recovered on appropriate selective and nonselective media containing the corresponding antibiotic. Log reductions and extent of injury were calculated and treatments were compared using ANOVA. No significant differences were observed in the reduction of cold-shocked or non-cold-shocked bacteria on products with or without skin that were crust or completely frozen. The average reduction for E. coli was 0.15 log(10) cfu/mL of rinse, and for Salmonella Typhimurium 0.10 log(10) cfu/mL of rinse; therefore, none of the final reductions were greater than the desired target (1 log). Bacterial cell injury was not significantly different (P > 0.05) among any of the treatments. Data showed no practical significance for initial reduction of these pathogens from crust freezing and thus, this technology should not be considered as a strategy for the reduction of E. coli and Salmonella Typhimurium on poultry.

Effect of Commercial Cyanobacteria Products on the Growth and Antagonistic Ability of Some Bioagents under Laboratory Conditions

PubMed Central

El-Mougy, Nehal S.; Abdel-Kader, Mokhtar M.

2013-01-01

Evaluation of the efficacy of blue-green algal compounds against the growth of either pathogenic or antagonistic microorganisms as well as their effect on the antagonistic ability of bioagents was studied under in vitro conditions. The present study was undertaken to explore the inhibitory effect of commercial algal compounds, Weed-Max and Oligo-Mix, against some soil-borne pathogens. In growth medium supplemented with these algal compounds, the linear growth of pathogenic fungi decreased by increasing tested concentrations of the two algal compounds. Complete reduction in pathogenic fungal growth was observed at 2% of both Weed-Max and Oligo-Mix. Gradual significant reduction in the pathogenic fungal growth was caused by the two bioagents and by increasing the concentrations of algal compounds Weed-Max and Oligo-Mix. The present work showed that commercial algal compounds, Weed-Max and Oligo-Mix, have potential for the suppression of soil-borne fungi and enhance the antagonistic ability of fungal, bacterial, and yeast bio-agents. PMID:24307948

Inactivation of Selected Bacterial Pathogens in Dairy Cattle Manure by Mesophilic Anaerobic Digestion (Balloon Type Digester)

PubMed Central

Manyi-Loh, Christy E.; Mamphweli, Sampson N.; Meyer, Edson L.; Okoh, Anthony I.; Makaka, Golden; Simon, Michael

2014-01-01

Anaerobic digestion of animal manure in biogas digesters has shown promise as a technology in reducing the microbial load to safe and recommended levels. We sought to treat dairy manure obtained from the Fort Hare Dairy Farm by investigating the survival rates of bacterial pathogens, through a total viable plate count method, before, during and after mesophilic anaerobic digestion. Different microbiological media were inoculated with different serial dilutions of manure samples that were withdrawn from the biogas digester at 3, 7 and 14 day intervals to determine the viable cells. Data obtained indicated that the pathogens of public health importance were 90%–99% reduced in the order: Campylobacter sp. (18 days) < Escherichia coli sp. (62 days) < Salmonella sp. (133 days) from a viable count of 10.1 × 103, 3.6 × 105, 7.4 × 103 to concentrations below the detection limit (DL = 102 cfu/g manure), respectively. This disparity in survival rates may be influenced by the inherent characteristics of these bacteria, available nutrients as well as the stages of the anaerobic digestion process. In addition, the highest p-value i.e., 0.957 for E. coli showed the statistical significance of its model and the strongest correlation between its reductions with days of digestion. In conclusion, the results demonstrated that the specific bacterial pathogens in manure can be considerably reduced through anaerobic digestion after 133 days. PMID:25026086

Down-regulation of Fusarium oxysporum endogenous genes by Host-Delivered RNA interference enhances disease resistance

NASA Astrophysics Data System (ADS)

Hu, Zongli; Parekh, Urvi; Maruta, Natsumi; Trusov, Yuri; Botella, Jimmy

2015-01-01

Fusarium oxysporum is a devastating pathogen causing extensive yield losses in a variety of crops and development of sustainable, environmentally friendly methods to improve crop resistance is crucial. We have used Host-Derived RNA interference (HD-RNAi) technology to partially silence three different genes (FOW2, FRP1 and OPR) in the hemi-biotrophic fungus Fusarium oxysporum f. sp. conglutinans. Expression of double stranded RNA molecules targeting fungal pathogen genes was achieved in a number of transgenic Arabidopsis lines. F. oxysporum infecting the transgenic lines displayed substantially reduced mRNA levels on all three targeted genes, with an average of 75%, 83% and 72% reduction for FOW2, FRP1 and OPR respectively. The silencing of pathogen genes had a clear positive effect on the ability of the transgenic lines to fight infection. All transgenic lines displayed enhanced resistance to F. oxysporum with delayed disease symptom development, especially FRP1 and OPR lines. Survival rates after fungal infection were higher in the transgenic lines compared to control wild type plants which consistently showed survival rates of 10%, with FOW2 lines showing 25% survival; FRP1 lines 30-50% survival and FOW2 between 45-70% survival. The down-regulation effect was specific for the targeted genes without unintended effects in related genes. In addition to producing resistant crops, HD-RNAi can provide a useful tool to rapidly screen candidate fungal pathogenicity genes without the need to produce fungal knockout mutants.

Disease Management in the Genomics Era-Summaries of Focus Issue Papers.

PubMed

Klosterman, S J; Rollins, J R; Sudarshana, M R; Vinatzer, B A

2016-10-01

The genomics revolution has contributed enormously to research and disease management applications in plant pathology. This development has rapidly increased our understanding of the molecular mechanisms underpinning pathogenesis and resistance, contributed novel markers for rapid pathogen detection and diagnosis, and offered further insights into the genetics of pathogen populations on a larger scale. The availability of whole genome resources coupled with next-generation sequencing (NGS) technologies has helped fuel genomics-based approaches to improve disease resistance in crops. NGS technologies have accelerated the pace at which whole plant and pathogen genomes have become available, and made possible the metagenomic analysis of plant-associated microbial communities. Furthermore, NGS technologies can now be applied routinely and cost effectively to rapidly generate plant and/or pathogen genome or transcriptome marker sequences associated with virulence phenotypes in the pathogen or resistance phenotypes in the plant, potentially leading to improvements in plant disease management. In some systems, investments in plant and pathogen genomics have led to immediate, tangible benefits. This focus issue covers some of the systems. The articles in this focus issue range from overall perspective articles to research articles describing specific genomics applications for detection and control of diseases caused by nematode, viral, bacterial, fungal, and oomycete pathogens. The following are representative short summaries of the articles that appear in this Focus Issue .

Prospects for a Novel Ultrashort Pulsed Laser Technology for Pathogen Inactivation

DTIC Science & Technology

2012-07-06

and Listeria [3-11]. The USP laser technology has the following advantages over the current methods of disinfection of pathogens: (1) With... Listeria monocytogenes Gram positive 10 3 Enterobacter Sakazakii Gram negative 10 3 (2) Existing disinfection methods such as irradiation of ultraviolet

Effect of in-house chicken litter composting on ammonia and nitrous oxide emissions and pathogen reduction

USDA-ARS?s Scientific Manuscript database

Inhouse composting is a management practice to reduce pathogen in poultry litter. In between flocks, growers windrow the litter inside the broiler houses. This results in high temperatures that can reduce some pathogens in the litter. However, this practice is likely to increase emissions of NH3 and...

Food decontamination using nanomaterials

USDA-ARS?s Scientific Manuscript database

The research indicates that nanomaterials including nanoemulsions are promising decontamination media for the reduction of food contaminating pathogens. The inhibitory effect of nanoparticles for pathogens could be due to deactivate cellular enzymes and DNA; disrupting of membrane permeability; and/...

Intervention technologies for food safety on minimally processed produce:Perspectives on food-borne and plant pathogens

USDA-ARS?s Scientific Manuscript database

Produce contamination associated with enteric pathogens such Escherichia coli O157:H7, salmonella spp., Listeria monocytogenes, Shigella and others are significant challenges to food safety. This is due to the illnesses and economic impacts resulting from the outbreaks. Innovative technologies for i...

Food Safety Impacts from Post-Harvest Processing Procedures of Molluscan Shellfish.

PubMed

Baker, George L

2016-04-18

Post-harvest Processing (PHP) methods are viable food processing methods employed to reduce human pathogens in molluscan shellfish that would normally be consumed raw, such as raw oysters on the half-shell. Efficacy of human pathogen reduction associated with PHP varies with respect to time, temperature, salinity, pressure, and process exposure. Regulatory requirements and PHP molluscan shellfish quality implications are major considerations for PHP usage. Food safety impacts associated with PHP of molluscan shellfish vary in their efficacy and may have synergistic outcomes when combined. Further research for many PHP methods are necessary and emerging PHP methods that result in minimal quality loss and effective human pathogen reduction should be explored.

Reducing the financial impact of pathogen inactivation technology for platelet components: our experience.

PubMed

Girona-Llobera, Enrique; Jimenez-Marco, Teresa; Galmes-Trueba, Ana; Muncunill, Josep; Serret, Carmen; Serra, Neus; Sedeño, Matilde

2014-01-01

Pathogen inactivation (PI) technology for blood components enhances blood safety by inactivating viruses, bacteria, parasites, and white blood cells. Additionally, PI for platelet (PLT) components has the potential to extend PLT storage time from 5 to 7 days. A retrospective analysis was conducted into the percentage of outdated PLT components during the 3 years before and after the adoption of PLT PI technology in our institution. The PLT transfusion dose for both pre-PI and post-PI periods was similar. A retrospective analysis to study clinical safety and component utilization was also performed in the Balearic Islands University Hospital. As a result of PI implementation in our institution, the PLT production cost increased by 85.5%. However, due to the extension of PLT storage time, the percentage of outdated PLT units substantially decreased (-83.9%) and, consequently, the cost associated with outdated units (-69.8%). This decrease represented a 13.7% reduction of the initial cost increase which, together with the saving in blood transportation (0.1%), led to a saving of 13.8% over the initial cost. Therefore, the initial 85.5% increase in the cost of PLT production was markedly reduced to 71.7%. The mean number of PLT concentrates per patient was similar during both periods. The extension of PLT storage time can substantially contribute to reducing the financial impact of PI by decreasing the percentage of outdated PLTs while improving blood safety. Since the adoption of PI, there have been no documented cases of PLT transfusion-related sepsis in our region. © 2013 American Association of Blood Banks.

Weighing environmental advantages and disadvantages of advanced wastewater treatment of micro-pollutants using environmental life cycle assessment.

PubMed

Wenzel, H; Larsen, H F; Clauson-Kaas, J; Høibye, L; Jacobsen, B N

2008-01-01

Much research and development effort is directed towards advances in municipal wastewater treatment aiming at reducing the effluent content of micro-pollutants and pathogens. The objective is to further reduce the eco-toxicity, hormone effects and pathogenic effects of the effluent. Such further polishing of the effluent, however, involves an environmental trade-off: the reduction in eco-toxicity, hormone effects, etc. will happen at the expense of increased resource- and energy consumption. Obviously, at some point of further advances, there must be an 'environmental break-even'. This trade-off was investigated using Life Cycle Assessment (LCA) methodology and based on a literature review of advanced treatment performance. The LCA evaluation comprised sand filtration, ozonation and MBRs and assessed the effect of extending existing tertiary treatment with these technologies on a variety of micro-pollutants being: heavy metals (Cd, Pb, Ni), endocrine disruptors (E2 and EE2), PAH, DEHP, and detergents (LAS & NPE). It was found, in some of the studied scenarios, that more environmental impact may be induced than removed by the advanced treatment. The study showed that for the 3 technologies, sand filtration has the best balance between prevented and induced impacts, and sand filtration proved to have a net environmental benefit under the assumptions used in the study. But the outcome of the study suggests that this is not always the case for ozonation and MBR.

Reduced MHC Alloimmunization and Partial Tolerance Protection With Pathogen Reduction Of Whole Blood

PubMed Central

Jackman, Rachael P.; Muench, Marcus O.; Inglis, Heather; Heitman, John W.; Marschner, Susanne; Goodrich, Raymond P.; Norris, Philip J.

2017-01-01

BACKGROUND Allogeneic blood transfusion can result in an immune response against major histocompatibility complex (MHC) antigens, potentially complicating future transfusions or transplants. We have previously shown that pathogen reduction of platelet-rich plasma (PRP) with riboflavin and UV light (UV+R) can prevent alloimmunization in mice. A similar pathogen reduction treatment is currently under development for the treatment of whole blood using riboflavin and a higher dose of UV light. We sought to determine the effectiveness of this treatment in prevention of alloimmunization. STUDY DESIGN AND METHODS BALB/c mice were transfused with untreated or UV+R treated allogeneic C57Bl/6 whole blood with or without leukoreduction. Mice were evaluated for donor specific antibodies and ex vivo splenocyte cytokine responses, as well as for changes in the frequency of regulatory T (Treg) cells. RESULTS UV+R treatment blocked cytokine priming and reduced anti-MHC alloantibody responses to transfused whole blood. Leukoreduction reduced alloantibody levels in both the untreated and UV+R groups. Mice transfused with UV+R treated whole blood had reduced alloantibody and cytokine responses when subsequently transfused with untreated blood from the same donor type. This reduction in responses was not associated with increased Treg cells. CONCLUSIONS Pathogen reduction of whole blood with UV+R significantly reduces, but does not eliminate the alloimmune response. Exposure to UV+R treated whole blood transfusion does appear to induce tolerance to alloantigens resulting in reduced anti-MHC alloantibody and cytokine responses to subsequent exposures to the same alloantigens. This tolerance does not appear to be driven by an increase in Treg cells. PMID:27859333

Centrifuge separation effect on bacterial indicator reduction in dairy manure.

PubMed

Liu, Zong; Carroll, Zachary S; Long, Sharon C; Roa-Espinosa, Aicardo; Runge, Troy

2017-04-15

Centrifugation is a commonly applied separation method for manure processing on large farms to separate solids and nutrients. Pathogen reduction is also an important consideration for managing manure. Appropriate treatment reduces risks from pathogen exposure when manure is used as soil amendments or the processed liquid stream is recycled to flush the barn. This study investigated the effects of centrifugation and polymer addition on bacterial indicator removal from the liquid fraction of manure slurries. Farm samples were taken from a manure centrifuge processing system. There were negligible changes of quantified pathogen indicator concentrations in the low-solids centrate compared to the influent slurry. To study if possible improvements could be made to the system, lab scale experiments were performed investigating a range of g-forces and flocculating polymer addition. The results demonstrated that polymer addition had a negligible effect on the indicator bacteria levels when centrifuged at high g forces. However, the higher g force centrifugation was capable of reducing bacterial indicator levels up to two-log 10 in the liquid stream of the manure, although at speeds higher than typical centrifuge operations currently used for manure processing applications. This study suggests manure centrifuge equipment could be redesigned to provide pathogen reduction to meet emerging issues, such as zoonotic pathogen control. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Evaluation of radio-frequency heating in controlling Salmonella enterica in raw shelled almonds.

PubMed

Jeong, Seul-Gi; Baik, Oon-Doo; Kang, Dong-Hyun

2017-08-02

This study was conducted to investigate the efficacy of radio-frequency (RF) heating to reduce Salmonella enterica serovars Enteritidis, Typhimurium, and Senftenberg in raw shelled almonds compared to conventional convective heating, and the effect of RF heating on quality by measuring changes in the color and degree of lipid oxidation. Agar-grown cells of three pathogens were inoculated onto the surface or inside of raw shelled almonds using surface inoculation or the vacuum perfusion method, respectively, and subjected to RF or conventional heating. RF heating for 40s achieved 3.7-, 6.0-, and 5.6-log reductions in surface-inoculated S. Enteritidis, S. Typhimurium, and S. Senftenberg, respectively, whereas the reduction of these pathogens following convective heating for 600s was 1.7, 2.5, and 3.7 log, respectively. RF heating reduced internally inoculated pathogens to below the detection limit (0.7 logCFU/g) after 30s. However, conventional convective heating did not attain comparable reductions even at the end of treatment (600s). Color values, peroxide values, and acid values of RF-treated (40-s treatment) almonds were not significantly (P>0.05) different from those of nontreated samples. These results suggest that RF heating can be applied to control internalized pathogens as well as surface-adhering pathogens in raw almonds without affecting product quality. Copyright © 2017. Published by Elsevier B.V.

Horse species symposium: a novel approach to monitoring pathogen progression during uterine and placental infection in the mare using bioluminescence imaging technology and lux-modified bacteria.

PubMed

Ryan, P L; Christiansen, D L; Hopper, R M; Walters, F K; Moulton, K; Curbelo, J; Greene, J M; Willard, S T

2011-05-01

Uterine and placental infections are the leading cause of abortion, stillbirth, and preterm delivery in the mare. Whereas uterine and placental infections in women have been studied extensively, a comprehensive examination of the pathogenic processes leading to this unsatisfactory pregnancy outcome in the mare has yet to be completed. Most information in the literature relating to late-term pregnancy loss in mares is based on retrospective studies of clinical cases submitted for necropsy. Here we report the development and application of a novel approach, whereby transgenically modified bacteria transformed with lux genes of Xenorhabdus luminescens or Photorhabdus luminescens origin and biophotonic imaging are utilized to better understand pathogen-induced preterm birth in late-term pregnant mares. This technology uses highly sensitive bioluminescence imaging camera systems to localize and monitor pathogen progression during tissue invasion by measuring the bioluminescent signatures emitted by the lux-modified pathogens. This method has an important advantage in that it allows for the potential tracking of pathogens in vivo in real time and over time, which was hitherto impossible. Although the application of this technology in domestic animals is in its infancy, investigators were successful in identifying the fetal lungs, sinuses, nares, urinary, and gastrointestinal systems as primary tissues for pathogen invasion after experimental infection of pregnant mares with lux-modified Escherichia coli. It is important that pathogens were not detected in other vital organs, such as the liver, brain, and cardiac system. Such precision in localizing sites of pathogen invasion provides potential application for this novel approach in the development of more targeted therapeutic interventions for pathogen-related diseases in the equine and other domestic species.

Enhanced Inactivation of Food-Borne Pathogens in Ready-To-Eat Sliced Ham by Near-Infrared Heating Combined with UV-C Irradiation and Mechanism of the Synergistic Bactericidal Action

PubMed Central

Ha, Jae-Won

2014-01-01

The objective of the study described in this article was, first, to investigate the effect of the simultaneous application of near-infrared (NIR) heating and UV irradiation on inactivation of Escherichia coli O157:H7, Salmonella enterica serovar Typhimurium, and Listeria monocytogenes in ready-to-eat (RTE) sliced ham and as well as its effect on product quality and, second, to elucidate the underlying mechanisms of the synergistic bactericidal action of NIR heating and UV irradiation. With the inoculation amounts used, simultaneous NIR-UV combined treatment for 70 s achieved 3.62, 4.17, and 3.43 log CFU reductions of E. coli O157:H7, S. Typhimurium, and L. monocytogenes, respectively. For all three pathogens, the simultaneous application of both technologies resulted in an additional log unit reduction as a result of their synergism compared to the sum of the reductions obtained after the individual treatments. To investigate the mechanisms of NIR-UV synergistic injury for a particular microorganism in a food base, we evaluated the effect of four types of metabolic inhibitors using the overlay method and confirmed that damage to cellular membranes and the inability of cells to repair these structures due to ribosomal damage were the primary factors related to the synergistic lethal effect. Additionally, NIR-UV combined treatment for a maximum of 70 s did not alter the color values or texture parameters of ham slices significantly (P > 0.05). These results suggest that a NIR-UV combined process could be an innovative antimicrobial intervention for RTE meat products. PMID:25107964

Enhanced inactivation of food-borne pathogens in ready-to-eat sliced ham by near-infrared heating combined with UV-C irradiation and mechanism of the synergistic bactericidal action.

PubMed

Ha, Jae-Won; Kang, Dong-Hyun

2015-01-01

The objective of the study described in this article was, first, to investigate the effect of the simultaneous application of near-infrared (NIR) heating and UV irradiation on inactivation of Escherichia coli O157:H7, Salmonella enterica serovar Typhimurium, and Listeria monocytogenes in ready-to-eat (RTE) sliced ham and as well as its effect on product quality and, second, to elucidate the underlying mechanisms of the synergistic bactericidal action of NIR heating and UV irradiation. With the inoculation amounts used, simultaneous NIR-UV combined treatment for 70 s achieved 3.62, 4.17, and 3.43 log CFU reductions of E. coli O157:H7, S. Typhimurium, and L. monocytogenes, respectively. For all three pathogens, the simultaneous application of both technologies resulted in an additional log unit reduction as a result of their synergism compared to the sum of the reductions obtained after the individual treatments. To investigate the mechanisms of NIR-UV synergistic injury for a particular microorganism in a food base, we evaluated the effect of four types of metabolic inhibitors using the overlay method and confirmed that damage to cellular membranes and the inability of cells to repair these structures due to ribosomal damage were the primary factors related to the synergistic lethal effect. Additionally, NIR-UV combined treatment for a maximum of 70 s did not alter the color values or texture parameters of ham slices significantly (P > 0.05). These results suggest that a NIR-UV combined process could be an innovative antimicrobial intervention for RTE meat products. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Risk-Based Treatment Targets for Onsite Non-Potable Water ...

EPA Pesticide Factsheets

This presentation presents risk-based enteric pathogen log reduction targets for non-potable and potable uses of a variety of alternative source waters (i.e., municipal wastewater, locally-collected greywater, rainwater, and stormwater). A probabilistic, forward Quantitative Microbial Risk Assessment (QMRA) was used to derive the pathogen log10 reduction targets (LRTs) that corresponded with an infection risk of either 10-4 per person per year (ppy) or 10-2 ppy. The QMRA accounted for variation in pathogen concentration and sporadic pathogen occurrence (when data were available) in source waters for reference pathogens Rotavirus, Adenovirus, Norovirus, Campylobacter spp., Salmonella spp., Giardia spp., and Cryptosporidium spp.. Non-potable uses included indoor use (for toilet flushing and clothes washing) with accidental ingestion of treated non-potable water (or cross connection with potable water), and unrestricted irrigation for outdoor use. Various exposure scenarios captured the uncertainty from key inputs, i.e., the pathogen concentration in source water; the volume of water ingested; and for the indoor use, the frequency of and the fraction of the population exposed to accidental ingestion. Both potable and non-potable uses required pathogen treatment for the selected waters and the LRT was generally greater for potable use than nonpotable indoor use and unrestricted irrigation. The difference in treatment requirements among source waters was driven by th

Interventions for the control of diarrhoeal diseases among young children: improving water supplies and excreta disposal facilities*

PubMed Central

Esrey, S. A.; Feachem, R. G.; Hughes, J. M.

1985-01-01

A theoretical model is proposed that relates the level of ingestion of diarrhoea-causing pathogens to the frequency of diarrhoea in the community. The implications of this model are that, in poor communities with inadequate water supply and excreta disposal, reducing the level of enteric pathogen ingestion by a given amount will have a greater impact on diarrhoea mortality rates than on morbidity rates, a greater impact on the incidence rate of severe diarrhoea than on that of mild diarrhoea, and a greater impact on diarrhoea caused by pathogens having high infectious doses than on diarrhoea caused by pathogens of a low infectious dose. The impact of water supply and sanitation on diarrhoea, related infections, nutritional status, and mortality is analysed by reviewing 67 studies from 28 countries. The median reductions in diarrhoea morbidity rates are 22% from all studies and 27% from a few better-designed studies. All studies of the impact on total mortality rates show a median reduction of 21%, while the few better-designed studies give a median reduction of 30%. Improvements in water quality have less of an impact than improvements in water availability or excreta disposal. PMID:3878742

Endogenous System Microbes as Treatment Process ...

EPA Pesticide Factsheets

Monitoring the efficacy of treatment strategies to remove pathogens in decentralized systems remains a challenge. Evaluating log reduction targets by measuring pathogen levels is hampered by their sporadic and low occurrence rates. Fecal indicator bacteria are used in centralized systems to indicate the presence of fecal pathogens, but are ineffective decentralized treatment process indicators as they generally occur at levels too low to assess log reduction targets. System challenge testing by spiking with high loads of fecal indicator organisms, like MS2 coliphage, has limitations, especially for large systems. Microbes that are endogenous to the decentralized system, occur in high abundances and mimic removal rates of bacterial, viral and/or parasitic protozoan pathogens during treatment could serve as alternative treatment process indicators to verify log reduction targets. To identify abundant microbes in wastewater, the bacterial and viral communities were examined using deep sequencing. Building infrastructure-associated bacteria, like Zoogloea, were observed as dominant members of the bacterial community in graywater. In blackwater, bacteriophage of the order Caudovirales constituted the majority of contiguous sequences from the viral community. This study identifies candidate treatment process indicators in decentralized systems that could be used to verify log removal during treatment. The association of the presence of treatment process indic

Pathogen reduction through additive-free short-wave UV light irradiation retains the optimal efficacy of human platelet lysate for the expansion of human bone marrow mesenchymal stem cells.

PubMed

Viau, Sabrina; Chabrand, Lucie; Eap, Sandy; Lorant, Judith; Rouger, Karl; Goudaliez, Francis; Sumian, Chryslain; Delorme, Bruno

2017-01-01

We recently developed and characterized a standardized and clinical grade human Platelet Lysate (hPL) that constitutes an advantageous substitute for fetal bovine serum (FBS) for human mesenchymal stem cell (hMSC) expansion required in cell therapy procedures, avoiding xenogenic risks (virological and immunological) and ethical issues. Because of the progressive use of pathogen-reduced (PR) labile blood components, and the requirement of ensuring the viral safety of raw materials for cell therapy products, we evaluated the impact of the novel procedure known as THERAFLEX UV-Platelets for pathogen reduction on hPL quality (growth factors content) and efficacy (as a medium supplement for hMSC expansion). This technology is based on short-wave ultraviolet light (UV-C) that induces non-reversible damages in DNA and RNA of pathogens while preserving protein structures and functions, and has the main advantage of not needing the addition of any photosensitizing additives (that might secondarily interfere with hMSCs). We applied the THERAFLEX UV-Platelets procedure on fresh platelet concentrates (PCs) suspended in platelet additive solution and prepared hPL from these treated PCs. We compared the quality and efficacy of PR-hPL with the corresponding non-PR ones. We found no impact on the content of five cytokines tested (EGF, bFGF, PDGF-AB, VEGF and IGF-1) but a significant decrease in TGF-ß1 (-21%, n = 11, p<0.01). We performed large-scale culture of hMSCs from bone marrow (BM) during three passages and showed that hPL or PR-hPL at 8% triggered comparable BM-hMSC proliferation as FBS at 10% plus bFGF. Moreover, after proliferation of hMSCs in an hPL- or PR-hPL-containing medium, their profile of membrane marker expression, their clonogenic potential and immunosuppressive properties were maintained, in comparison with BM-hMSCs cultured under FBS conditions. The potential to differentiate towards the adipogenic and osteogenic lineages of hMSCs cultured in parallel in the three conditions also remained identical. We demonstrated the feasibility of using UV-C-treated platelets to subsequently obtain pathogen-reduced hPL, while preserving its optimal quality and efficacy for hMSC expansion in cell therapy applications.

Pathogen reduction through additive-free short-wave UV light irradiation retains the optimal efficacy of human platelet lysate for the expansion of human bone marrow mesenchymal stem cells

PubMed Central

Viau, Sabrina; Chabrand, Lucie; Eap, Sandy; Lorant, Judith; Rouger, Karl; Goudaliez, Francis; Sumian, Chryslain; Delorme, Bruno

2017-01-01

Background We recently developed and characterized a standardized and clinical grade human Platelet Lysate (hPL) that constitutes an advantageous substitute for fetal bovine serum (FBS) for human mesenchymal stem cell (hMSC) expansion required in cell therapy procedures, avoiding xenogenic risks (virological and immunological) and ethical issues. Because of the progressive use of pathogen-reduced (PR) labile blood components, and the requirement of ensuring the viral safety of raw materials for cell therapy products, we evaluated the impact of the novel procedure known as THERAFLEX UV-Platelets for pathogen reduction on hPL quality (growth factors content) and efficacy (as a medium supplement for hMSC expansion). This technology is based on short-wave ultraviolet light (UV-C) that induces non-reversible damages in DNA and RNA of pathogens while preserving protein structures and functions, and has the main advantage of not needing the addition of any photosensitizing additives (that might secondarily interfere with hMSCs). Methodology / Principal findings We applied the THERAFLEX UV-Platelets procedure on fresh platelet concentrates (PCs) suspended in platelet additive solution and prepared hPL from these treated PCs. We compared the quality and efficacy of PR-hPL with the corresponding non-PR ones. We found no impact on the content of five cytokines tested (EGF, bFGF, PDGF-AB, VEGF and IGF-1) but a significant decrease in TGF-ß1 (-21%, n = 11, p<0.01). We performed large-scale culture of hMSCs from bone marrow (BM) during three passages and showed that hPL or PR-hPL at 8% triggered comparable BM-hMSC proliferation as FBS at 10% plus bFGF. Moreover, after proliferation of hMSCs in an hPL- or PR-hPL-containing medium, their profile of membrane marker expression, their clonogenic potential and immunosuppressive properties were maintained, in comparison with BM-hMSCs cultured under FBS conditions. The potential to differentiate towards the adipogenic and osteogenic lineages of hMSCs cultured in parallel in the three conditions also remained identical. Conclusion / Significance We demonstrated the feasibility of using UV-C-treated platelets to subsequently obtain pathogen-reduced hPL, while preserving its optimal quality and efficacy for hMSC expansion in cell therapy applications. PMID:28763452

Control of extraintestinal foodborne pathogens using intervention technologies

USDA-ARS?s Scientific Manuscript database

In recent years it has become apparent that emerging foodborne pathogens including Extraintestinal Pathogenic Escherichia coli (ExPEC), Staphylococcus saprophyticus, and Klebsiella pneumoniae are associated with human health conditions such as inflammatory bowel disease (IBD), ulcerative colitis (UC...

Tinidazole inhibitory and cidal activity against anaerobic periodontal pathogens.

PubMed

Alou, L; Giménez, M J; Manso, F; Sevillano, D; Torrico, M; González, N; Granizo, J J; Bascones, A; Prieto, J; Maestre, J R; Aguilar, L

2009-05-01

The in vitro activity of tinidazole against anaerobic periodontal pathogens (25 Prevotella buccae, 18 Prevotella denticola, 10 Prevotella intermedia, 6 Prevotella melaninogenica, 5 Prevotella oralis, 10 Fusobacterium nucleatum and 8 Veillonella spp.) was determined by agar dilution. MIC(90) values (minimum inhibitory concentration for 90% of the organisms) were 8 microg/mL for Veillonella spp., 4 microg/mL for P. intermedia, 2 microg/mL for P. buccae, 1 microg/mL for Fusobacterium spp. and 0.5 microg/mL for other Prevotella spp. Cidal activity was studied by killing curves with tinidazole and amoxicillin (alone and in combination) at concentrations similar to those achieved in crevicular fluid (41.2 microg/mL tinidazole and 14.05 microg/mL amoxicillin) against an inoculum of ca. 10(7)colony-forming units/mL of four bacterial groups, each one composed of four different strains of the following periodontal isolates: Prevotella spp., Fusobacterium spp. and Veillonella spp. (anaerobes) and one amoxicillin-susceptible Streptococcus spp. (facultative) in a proportion of 1:1:1:1. When only beta-lactamase-negative Prevotella or Fusobacterium strains were tested, significantly higher reductions were found with amoxicillin (>4 log reduction at 48 h) versus controls. The presence of beta-lactamase-positive Prevotella spp. or F. nucleatum strains rendered amoxicillin inactive (no reductions at 48 h), with no differences from controls. Amoxicillin+tinidazole produced >3 log reduction at 24h and >4 log reduction at 48 h regardless of the presence or not of beta-lactamase-positive strains. The presence in crevicular fluid of beta-lactamases produced by beta-lactamase-positive periodontal pathogens may have ecological and therapeutic consequences since it may protect beta-lactamase-negative periodontal pathogens from amoxicillin treatment. In vitro, tinidazole offered high antianaerobic activity against beta-lactamase-positive and -negative periodontal pathogens, avoiding amoxicillin inactivation.

Genomic paradigms for food-borne enteric pathogen analysis at the USFDA: case studies highlighting method utility, integration and resolution.

PubMed

Elkins, C A; Kotewicz, M L; Jackson, S A; Lacher, D W; Abu-Ali, G S; Patel, I R

2013-01-01

Modern risk control and food safety practices involving food-borne bacterial pathogens are benefiting from new genomic technologies for rapid, yet highly specific, strain characterisations. Within the United States Food and Drug Administration (USFDA) Center for Food Safety and Applied Nutrition (CFSAN), optical genome mapping and DNA microarray genotyping have been used for several years to quickly assess genomic architecture and gene content, respectively, for outbreak strain subtyping and to enhance retrospective trace-back analyses. The application and relative utility of each method varies with outbreak scenario and the suspect pathogen, with comparative analytical power enhanced by database scale and depth. Integration of these two technologies allows high-resolution scrutiny of the genomic landscapes of enteric food-borne pathogens with notable examples including Shiga toxin-producing Escherichia coli (STEC) and Salmonella enterica serovars from a variety of food commodities. Moreover, the recent application of whole genome sequencing technologies to food-borne pathogen outbreaks and surveillance has enhanced resolution to the single nucleotide scale. This new wealth of sequence data will support more refined next-generation custom microarray designs, targeted re-sequencing and "genomic signature recognition" approaches involving a combination of genes and single nucleotide polymorphism detection to distil strain-specific fingerprinting to a minimised scale. This paper examines the utility of microarrays and optical mapping in analysing outbreaks, reviews best practices and the limits of these technologies for pathogen differentiation, and it considers future integration with whole genome sequencing efforts.

40 CFR 503.30 - Scope.

Code of Federal Regulations, 2011 CFR

2011-07-01

... DISPOSAL OF SEWAGE SLUDGE Pathogens and Vector Attraction Reduction § 503.30 Scope. (a) This subpart... land, forest, or a reclamation site. (d) This subpart contains alternative vector attraction reduction...

40 CFR 503.30 - Scope.

Code of Federal Regulations, 2010 CFR

2010-07-01

... DISPOSAL OF SEWAGE SLUDGE Pathogens and Vector Attraction Reduction § 503.30 Scope. (a) This subpart... land, forest, or a reclamation site. (d) This subpart contains alternative vector attraction reduction...

Technical Transformation of Biodefense Vaccines

PubMed Central

Lu, Shan; Wang, Shixia

2013-01-01

Biodefense vaccines are developed against a diverse group of pathogens. Vaccines were developed for some of these pathogens a long time ago but they are facing new challenges to move beyond the old manufacturing technologies. New vaccines to be developed against other pathogens have to determine whether to follow traditional vaccination strategies or to seek new approaches. Advances in basic immunology and recombinant DNA technology have fundamentally transformed the process of formulating a vaccine concept, optimizing protective antigens, and selecting the most effective vaccine delivery approach for candidate biodefense vaccines. PMID:19837293

Strategies for reducing the risk of transfusion-transmitted leishmaniasis in an area endemic for Leishmania infantum: a patient- and donor-targeted approach

PubMed Central

Riera, Cristina; Girona-Llobera, Enrique; Guillen, Carmen; Iniesta, Laura; Alcover, Magdalena; Berenguer, Diana; Pujol, Alba; Tomás-Pérez, Miriam; Cancino-Faure, Beatriz; Serra, Teresa; Mascaró, Martín; Gascó, Joan; Fisa, Roser

2018-01-01

Background In the Balearic Islands, as in other areas of the Mediterranean basin, there is a significant proportion of asymptomatic Leishmania (L.) infantum-infected blood donors, who may represent an important threat to transfusion safety. The Balearic Islands blood bank, located in an area endemic for L. infantum, carried out a study of donors and patients to investigate the impact of this infectious disease on blood safety in the region. Materials and methods Twenty asymptomatic Leishmania-infected blood donors were followed-up between 2008 and 2011 to investigate the evolution of Leishmania infection in asymptomatic carriers. Their blood was periodically tested for anti-Leishmania antibodies by western blot and for Leishmania DNA by quantitative polymerase chain reaction (qPCR). Additionally, the prevalence of L. infantum infection was investigated in a group of 68 multiply transfused patients to ascertain the risk of transfusion-transmitted leishmaniasis (TTL) in the region, taking into account regular blood component production practices such as pre-storage leucodepletion and pathogen reduction technology. Results All 20 donors remained asymptomatic over the study period (2008–2011). Most donors had repeatedly positive qPCR results, either persistently or intermittently, but showed no symptoms of Leishmaniasis. Levels of parasitaemia were remarkably low in asymptomatic donors, with values ≤1 parasite/mL. Despite multiple transfusions received over 15 years, no transfused patient studied was infected with L. infantum. Discussion L. infantum-infected donors can remain asymptomatic for at least 3 years. In our region, no cases of TTL were detected, despite an active search in multiply transfused patients. This seems to be related to two independent variables: (i) a low concentration of the parasite in the peripheral blood of asymptomatic carriers and (ii) the application of methods with proven efficacy against TTL, such as leucodepletion and pathogen reduction technology. PMID:28488962

Tertiary treatment using microfiltration and UV disinfection for water reclamation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jolis, D.; Hirano, R.; Pitt, P.

Microfiltration and UV disinfection are two alternative technologies for water reclamation. The results of a pilot study combining these two processes are presented. In addition to producing filtrate turbidites averaging 0.06 nephelometric turbidity units, microfiltration was an effective barrier to pathogens, demonstrating average log reductions of 4.5 for total coliforms and 2.9 for MS2 bacteriophage. Ultraviolet disinfection following microfiltration reliably met the California Wastewater Reclamation Criteria (Title 22) total coliform standard of 2.2 colony-forming units/100 mL at a UV dose of 450 J/m{sup 2}. The MS2 bacteriophage standard, which requires a 5-log reduction, was achieved by microfiltration and a UVmore » dose of 880 J/m{sup 2}. A model of the kinetics of inactivation of MS2 bacteriophage was used in further analysis of disinfection data. The model indicated that considerable backmixing occurred in the pilot UV disinfection unit, and observed UV doses could be reduced with improved hydraulics.« less

Use of encapsulated bacteriophages to enhance farm to fork food safety.

PubMed

Hussain, Malik A; Liu, Huan; Wang, Qi; Zhong, Fang; Guo, Qian; Balamurugan, Sampathkumar

2017-09-02

Bacteriophages have been successfully applied to control the growth of pathogens in foods and to reduce the colonization and shedding of pathogens by food animals. They are set to play a dominant role in food safety in the future. However, many food-processing operations and the microenvironments in food animals' guts inactivate phages and reduce their infectivity. Encapsulation technologies have been used successfully to protect phages against extreme environments, and have been shown to preserve their activity and enable their release in targeted environments. A number of encapsulation technologies have shown potential for use with bacteriophages. This review discusses the current state of knowledge about the use of encapsulation technologies with bacteriophages to control pathogens in foods and food animals.

Using NextRAD sequencing to infer movement of herbivores among host plants.

PubMed

Fu, Zhen; Epstein, Brendan; Kelley, Joanna L; Zheng, Qi; Bergland, Alan O; Castillo Carrillo, Carmen I; Jensen, Andrew S; Dahan, Jennifer; Karasev, Alexander V; Snyder, William E

2017-01-01

Herbivores often move among spatially interspersed host plants, tracking high-quality resources through space and time. This dispersal is of particular interest for vectors of plant pathogens. Existing molecular tools to track such movement have yielded important insights, but often provide insufficient genetic resolution to infer spread at finer spatiotemporal scales. Here, we explore the use of Nextera-tagmented reductively-amplified DNA (NextRAD) sequencing to infer movement of a highly-mobile winged insect, the potato psyllid (Bactericera cockerelli), among host plants. The psyllid vectors the pathogen that causes zebra chip disease in potato (Solanum tuberosum), but understanding and managing the spread of this pathogen is limited by uncertainty about the insect's host plant(s) outside of the growing season. We identified 1,978 polymorphic loci among psyllids separated spatiotemporally on potato or in patches of bittersweet nightshade (S. dulcumara), a weedy plant proposed to be the source of potato-colonizing psyllids. A subset of the psyllids on potato exhibited genetic similarity to insects on nightshade, consistent with regular movement between these two host plants. However, a second subset of potato-collected psyllids was genetically distinct from those collected on bittersweet nightshade; this suggests that a currently unrecognized source, i.e., other nightshade patches or a third host-plant species, could be contributing to psyllid populations in potato. Oftentimes, dispersal of vectors of pathogens must be tracked at a fine scale in order to understand, predict, and manage disease spread. We demonstrate that emerging sequencing technologies that detect genome-wide SNPs of a vector can be used to infer such localized movement.

Advanced DNA-Based Point-of-Care Diagnostic Methods for Plant Diseases Detection.

PubMed

Lau, Han Yih; Botella, Jose R

2017-01-01

Diagnostic technologies for the detection of plant pathogens with point-of-care capability and high multiplexing ability are an essential tool in the fight to reduce the large agricultural production losses caused by plant diseases. The main desirable characteristics for such diagnostic assays are high specificity, sensitivity, reproducibility, quickness, cost efficiency and high-throughput multiplex detection capability. This article describes and discusses various DNA-based point-of care diagnostic methods for applications in plant disease detection. Polymerase chain reaction (PCR) is the most common DNA amplification technology used for detecting various plant and animal pathogens. However, subsequent to PCR based assays, several types of nucleic acid amplification technologies have been developed to achieve higher sensitivity, rapid detection as well as suitable for field applications such as loop-mediated isothermal amplification, helicase-dependent amplification, rolling circle amplification, recombinase polymerase amplification, and molecular inversion probe. The principle behind these technologies has been thoroughly discussed in several review papers; herein we emphasize the application of these technologies to detect plant pathogens by outlining the advantages and disadvantages of each technology in detail.

Advanced DNA-Based Point-of-Care Diagnostic Methods for Plant Diseases Detection

PubMed Central

Lau, Han Yih; Botella, Jose R.

2017-01-01

Diagnostic technologies for the detection of plant pathogens with point-of-care capability and high multiplexing ability are an essential tool in the fight to reduce the large agricultural production losses caused by plant diseases. The main desirable characteristics for such diagnostic assays are high specificity, sensitivity, reproducibility, quickness, cost efficiency and high-throughput multiplex detection capability. This article describes and discusses various DNA-based point-of care diagnostic methods for applications in plant disease detection. Polymerase chain reaction (PCR) is the most common DNA amplification technology used for detecting various plant and animal pathogens. However, subsequent to PCR based assays, several types of nucleic acid amplification technologies have been developed to achieve higher sensitivity, rapid detection as well as suitable for field applications such as loop-mediated isothermal amplification, helicase-dependent amplification, rolling circle amplification, recombinase polymerase amplification, and molecular inversion probe. The principle behind these technologies has been thoroughly discussed in several review papers; herein we emphasize the application of these technologies to detect plant pathogens by outlining the advantages and disadvantages of each technology in detail. PMID:29375588

Transcriptome Analysis Based on RNA-Seq in Understanding Pathogenic Mechanisms of Diseases and the Immune System of Fish: A Comprehensive Review

PubMed Central

Sudhagar, Arun; El-Matbouli, Mansour

2018-01-01

In recent years, with the advent of next-generation sequencing along with the development of various bioinformatics tools, RNA sequencing (RNA-Seq)-based transcriptome analysis has become much more affordable in the field of biological research. This technique has even opened up avenues to explore the transcriptome of non-model organisms for which a reference genome is not available. This has made fish health researchers march towards this technology to understand pathogenic processes and immune reactions in fish during the event of infection. Recent studies using this technology have altered and updated the previous understanding of many diseases in fish. RNA-Seq has been employed in the understanding of fish pathogens like bacteria, virus, parasites, and oomycetes. Also, it has been helpful in unraveling the immune mechanisms in fish. Additionally, RNA-Seq technology has made its way for future works, such as genetic linkage mapping, quantitative trait analysis, disease-resistant strain or broodstock selection, and the development of effective vaccines and therapies. Until now, there are no reviews that comprehensively summarize the studies which made use of RNA-Seq to explore the mechanisms of infection of pathogens and the defense strategies of fish hosts. This review aims to summarize the contemporary understanding and findings with regard to infectious pathogens and the immune system of fish that have been achieved through RNA-Seq technology. PMID:29342931

Hydrothermal carbonization of livestock mortality for the reduction of pathogens and microbially-derived DNA

USDA-ARS?s Scientific Manuscript database

Hydrothermal carbonization (HTC), utilizing high temperature and pressure, has the potential to treat agricultural waste and inactivate pathogens, antibiotic resistance genes (ARG), and contaminants of emerging concern (CEC) in an environmentally and economically friendly manner. Livestock mortality...

Evaluation of near-infrared pasteurization in controlling Escherichia coli O157:H7, Salmonella enterica serovar typhimurium, and Listeria monocytogenes in ready-to-eat sliced ham.

PubMed

Ha, Jae-Won; Ryu, Sang-Ryeol; Kang, Dong-Hyun

2012-09-01

This study was conducted to investigate the efficacy of near-infrared (NIR) heating to reduce Salmonella enterica serovar Typhimurium, Escherichia coli O157:H7, and Listeria monocytogenes in ready-to-eat (RTE) sliced ham compared to conventional convective heating, and the effect of NIR heating on quality was determined by measuring the color and texture change. A cocktail of three pathogens was inoculated on the exposed or protected surfaces of ham slices, followed by NIR or conventional heating at 1.8 kW. NIR heating for 50 s achieved 4.1-, 4.19-, and 3.38-log reductions in surface-inoculated S. Typhimurium, E. coli O157:H7, and L. monocytogenes, respectively, whereas convective heating needed 180 s to attain comparable reductions for each pathogen. There were no statistically significant (P > 0.05) differences in reduction between surface- and internally inoculated pathogens at the end of NIR treatment (50 s). However, when treated with conventional convective heating, significant (P < 0.05) differences were observed at the final stages of the treatment (150 and 180 s). Color values and texture parameters of NIR-treated (50-s treatment) ham slices were not significantly (P > 0.05) different from those of nontreated samples. These results suggest that NIR heating can be applied to control internalized pathogens as well as surface-adhering pathogens in RTE sliced meats without affecting product quality.

Evaluation of Near-Infrared Pasteurization in Controlling Escherichia coli O157:H7, Salmonella enterica Serovar Typhimurium, and Listeria monocytogenes in Ready-To-Eat Sliced Ham

PubMed Central

Ha, Jae-Won; Ryu, Sang-Ryeol

2012-01-01

This study was conducted to investigate the efficacy of near-infrared (NIR) heating to reduce Salmonella enterica serovar Typhimurium, Escherichia coli O157:H7, and Listeria monocytogenes in ready-to-eat (RTE) sliced ham compared to conventional convective heating, and the effect of NIR heating on quality was determined by measuring the color and texture change. A cocktail of three pathogens was inoculated on the exposed or protected surfaces of ham slices, followed by NIR or conventional heating at 1.8 kW. NIR heating for 50 s achieved 4.1-, 4.19-, and 3.38-log reductions in surface-inoculated S. Typhimurium, E. coli O157:H7, and L. monocytogenes, respectively, whereas convective heating needed 180 s to attain comparable reductions for each pathogen. There were no statistically significant (P > 0.05) differences in reduction between surface- and internally inoculated pathogens at the end of NIR treatment (50 s). However, when treated with conventional convective heating, significant (P < 0.05) differences were observed at the final stages of the treatment (150 and 180 s). Color values and texture parameters of NIR-treated (50-s treatment) ham slices were not significantly (P > 0.05) different from those of nontreated samples. These results suggest that NIR heating can be applied to control internalized pathogens as well as surface-adhering pathogens in RTE sliced meats without affecting product quality. PMID:22773635

Tomorrow's vector vaccines for small ruminants.

PubMed

Kyriakis, C S

2015-12-14

Inactivated and attenuated vaccines have contributed to the control or even the eradication of significant animal pathogens. However, these traditional vaccine technologies have limitations and disadvantages. Inactivated vaccines lack efficacy against certain pathogens, while attenuated vaccines are not always as safe. New technology vaccines, namely DNA and recombinant viral vector vaccines, are being developed and tested against pathogens of small ruminants. These vaccines induce both humoral and cellular immune responses, are safe to manufacture and use and can be utilized in strategies for differentiation of infected from vaccinated animals. Although there are more strict regulatory requirements for the safety standards of these vaccines, once a vaccine platform is evaluated and established, effective vaccines can be rapidly produced and deployed in the field to prevent spread of emerging pathogens. The present article offers an introduction to these next generation technologies and examples of vaccines that have been tested against important diseases of sheep and goats. Copyright © 2015 Elsevier B.V. All rights reserved.

Pathogen reduction requirements for direct potable reuse in Antarctica: evaluating human health risks in small communities.

PubMed

Barker, S Fiona; Packer, Michael; Scales, Peter J; Gray, Stephen; Snape, Ian; Hamilton, Andrew J

2013-09-01

Small, remote communities often have limited access to energy and water. Direct potable reuse of treated wastewater has recently gained attention as a potential solution for water-stressed regions, but requires further evaluation specific to small communities. The required pathogen reduction needed for safe implementation of direct potable reuse of treated sewage is an important consideration but these are typically quantified for larger communities and cities. A quantitative microbial risk assessment (QMRA) was conducted, using norovirus, giardia and Campylobacter as reference pathogens, to determine the level of treatment required to meet the tolerable annual disease burden of 10(-6) DALYs per person per year, using Davis Station in Antarctica as an example of a small remote community. Two scenarios were compared: published municipal sewage pathogen loads and estimated pathogen loads during a gastroenteritis outbreak. For the municipal sewage scenario, estimated required log10 reductions were 6.9, 8.0 and 7.4 for norovirus, giardia and Campylobacter respectively, while for the outbreak scenario the values were 12.1, 10.4 and 12.3 (95th percentiles). Pathogen concentrations are higher under outbreak conditions as a function of the relatively greater degree of contact between community members in a small population, compared with interactions in a large city, resulting in a higher proportion of the population being at risk of infection and illness. While the estimates of outbreak conditions may overestimate sewage concentration to some degree, the results suggest that additional treatment barriers would be required to achieve regulatory compliance for safe drinking water in small communities. Copyright © 2013 Elsevier B.V. All rights reserved.

Endogenous System Microbes as Treatment Process Indicators for Decentralized Non-potable Water Reuse

EPA Science Inventory

Monitoring the efficacy of treatment strategies to remove pathogens in decentralized systems remains a challenge. Evaluating log reduction targets by measuring pathogen levels is hampered by their sporadic and low occurrence rates. Fecal indicator bacteria are used in centraliz...

Plant-pathogen interactions: what microarray tells about it?

PubMed

Lodha, T D; Basak, J

2012-01-01

Plant defense responses are mediated by elementary regulatory proteins that affect expression of thousands of genes. Over the last decade, microarray technology has played a key role in deciphering the underlying networks of gene regulation in plants that lead to a wide variety of defence responses. Microarray is an important tool to quantify and profile the expression of thousands of genes simultaneously, with two main aims: (1) gene discovery and (2) global expression profiling. Several microarray technologies are currently in use; most include a glass slide platform with spotted cDNA or oligonucleotides. Till date, microarray technology has been used in the identification of regulatory genes, end-point defence genes, to understand the signal transduction processes underlying disease resistance and its intimate links to other physiological pathways. Microarray technology can be used for in-depth, simultaneous profiling of host/pathogen genes as the disease progresses from infection to resistance/susceptibility at different developmental stages of the host, which can be done in different environments, for clearer understanding of the processes involved. A thorough knowledge of plant disease resistance using successful combination of microarray and other high throughput techniques, as well as biochemical, genetic, and cell biological experiments is needed for practical application to secure and stabilize yield of many crop plants. This review starts with a brief introduction to microarray technology, followed by the basics of plant-pathogen interaction, the use of DNA microarrays over the last decade to unravel the mysteries of plant-pathogen interaction, and ends with the future prospects of this technology.

Simulation of enteric pathogen concentrations in locally-collected greywater and wastewater for microbial risk assessments

EPA Science Inventory

As decentralized water reuse continues to gain popularity, risk-based treatment guidance is increasingly sought for the protection of public health. However, efforts to evaluate pathogen risks and log-reduction requirements have been hindered by an incomplete understanding of pat...

UPDATE ON PEC ACTIVITIES INCLUDING NEW EVALUATION CRITERIA, THE APPLICATION COMPLETENESS CHECKLIST, AND STATUS OF THE WEBSITE DEVELOPMENT

EPA Science Inventory

US EPA's Pathogen Equivalency Committee (PEC) has updated the evaluation criteria it uses to make recommendations of equivalency (to processes acceptable under 40CFR503) on innovative or alternative sludge pathogen reduction processes. These criteria will be presented along with ...

Physical and chemical interventions to mitigate risk associated with leafy greens

USDA-ARS?s Scientific Manuscript database

Contamination of leafy green vegetables with human pathogens is a source of ongoing concern for consumers. Conventional treatments have typically been able to achieve 1-2 logs reductions of such pathogens as Salmonella, Escherichia coli O157:H7 and Listeria monocytogenes. Novel approaches and treatm...

Enhanced salmonella reduction on tomatoes washed in chlorinated water with wash aid T-128

USDA-ARS?s Scientific Manuscript database

Chlorine is widely used by the fresh and fresh-cut produce industries to reduce microbial populations and to prevent potential pathogen cross contamination during produce washing. However, the organic materials released from produce quickly react with chlorine and degrade its efficacy for pathogen i...

Review of pathogen treatment reductions for onsite non-potable reuse of alternative source waters

EPA Science Inventory

Communities face a challenge when implementing onsite reuse of collected waters for non-potable purposes given the lack of national microbial standards. Quantitative Microbial Risk Assessment (QMRA) can be used to predict the pathogen risks associated with the non-potable reuse o...

Characterization of novel sufraces by FTIR spectroscopy and atomic force microscopy for food pathogen detection

USDA-ARS?s Scientific Manuscript database

Single molecular detection of pathogens and toxins of interest to food safety is within grasp using technology such as Atomic Force Microscopy. Using antibodies or specific aptamers connected to the AFM tip make it possible to detect a pathogen molecule on a surface. However, it also becomes necess...

The Effect of Antibiotic Exposure and Specimen Volume on the Detection of Bacterial Pathogens in Children With Pneumonia.

PubMed

Driscoll, Amanda J; Deloria Knoll, Maria; Hammitt, Laura L; Baggett, Henry C; Brooks, W Abdullah; Feikin, Daniel R; Kotloff, Karen L; Levine, Orin S; Madhi, Shabir A; O'Brien, Katherine L; Scott, J Anthony G; Thea, Donald M; Howie, Stephen R C; Adrian, Peter V; Ahmed, Dilruba; DeLuca, Andrea N; Ebruke, Bernard E; Gitahi, Caroline; Higdon, Melissa M; Kaewpan, Anek; Karani, Angela; Karron, Ruth A; Mazumder, Razib; McLellan, Jessica; Moore, David P; Mwananyanda, Lawrence; Park, Daniel E; Prosperi, Christine; Rhodes, Julia; Saifullah, Md; Seidenberg, Phil; Sow, Samba O; Tamboura, Boubou; Zeger, Scott L; Murdoch, David R

2017-06-15

Antibiotic exposure and specimen volume are known to affect pathogen detection by culture. Here we assess their effects on bacterial pathogen detection by both culture and polymerase chain reaction (PCR) in children. PERCH (Pneumonia Etiology Research for Child Health) is a case-control study of pneumonia in children aged 1-59 months investigating pathogens in blood, nasopharyngeal/oropharyngeal (NP/OP) swabs, and induced sputum by culture and PCR. Antibiotic exposure was ascertained by serum bioassay, and for cases, by a record of antibiotic treatment prior to specimen collection. Inoculated blood culture bottles were weighed to estimate volume. Antibiotic exposure ranged by specimen type from 43.5% to 81.7% in 4223 cases and was detected in 2.3% of 4863 controls. Antibiotics were associated with a 45% reduction in blood culture yield and approximately 20% reduction in yield from induced sputum culture. Reduction in yield of Streptococcus pneumoniae from NP culture was approximately 30% in cases and approximately 32% in controls. Several bacteria had significant but marginal reductions (by 5%-7%) in detection by PCR in NP/OP swabs from both cases and controls, with the exception of S. pneumoniae in exposed controls, which was detected 25% less frequently compared to nonexposed controls. Bacterial detection in induced sputum by PCR decreased 7% for exposed compared to nonexposed cases. For every additional 1 mL of blood culture specimen collected, microbial yield increased 0.51% (95% confidence interval, 0.47%-0.54%), from 2% when volume was ≤1 mL to approximately 6% for ≥3 mL. Antibiotic exposure and blood culture volume affect detection of bacterial pathogens in children with pneumonia and should be accounted for in studies of etiology and in clinical management. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

Combination treatment of chlorine dioxide gas and aerosolized sanitizer for inactivating foodborne pathogens on spinach leaves and tomatoes.

PubMed

Park, Sang-Hyun; Kang, Dong-Hyun

2015-08-17

The objective of this study was to evaluate the antimicrobial effect of chlorine dioxide (ClO2) gas and aerosolized sanitizer, when applied alone or in combination, on the survival of Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes inoculated onto spinach leaves and tomato surfaces. Spinach leaves and tomatoes were inoculated with a cocktail of three strains each of the three foodborne pathogens. ClO2 gas (5 or 10 ppmv) and aerosolized peracetic acid (PAA) (80 ppm) were applied alone or in combination for 20 min. Exposure to 10 ppmv of ClO2 gas for 20 min resulted in 3.4, 3.3, and 3.4 log reductions of E. coli O157:H7, S. Typhimurium, and L. monocytogenes on spinach leaves, respectively. Treatment with 80 ppm of aerosolized PAA for 20 min caused 2.3, 1.9, and 0.8 log reductions of E. coli O157:H7, S. Typhimurium, and L. monocytogenes, respectively. Combined treatment of ClO2 gas (10 ppmv) and aerosolized PAA (80 ppm) for 20 min caused 5.4, 5.1, and 4.1 log reductions of E. coli O157:H7, S. Typhimurium, and L. monocytogenes, respectively. E. coli O157:H7, S. Typhimurium, and L. monocytogenes on tomatoes experienced similar reduction patterns to those on spinach leaves. As treatment time increased, most combinations of ClO2 gas and aerosolized PAA showed additive effects in the inactivation of the three pathogens. Combined treatment of ClO2 gas and aerosolized PAA produced injured cells of three pathogens on spinach leaves while generally did not produce injured cells of these pathogens on tomatoes. Combined treatment of ClO2 gas (10 ppmv) and aerosolized PAA (80 ppm) did not significantly (p>0.05) affect the color and texture of samples during 7 days of storage. Copyright © 2015. Published by Elsevier B.V.

Infectious Causes of Cholesteatoma and Treatment of Infected Ossicles prior to Reimplantation by Hydrostatic High-Pressure Inactivation

PubMed Central

Hinz, Rebecca

2015-01-01

Chronic inflammation, which is caused by recurrent infections, is one of the factors contributing to the pathogenesis of cholesteatoma. If reimplantation of autologous ossicles after a surgical intervention is intended, inactivation of planktonic bacteria and biofilms is desirable. High hydrostatic pressure treatment is a procedure, which has been used to inactivate cholesteatoma cells on ossicles. Here we discuss the potential inactivating effect of high hydrostatic pressure on microbial pathogens including biofilms. Recent experimental data suggest an incomplete inactivation at a pressure level, which is tolerable for the bone substance of ossicles and results at least in a considerable reduction of pathogen load. Further studies are necessary to access how far this quantitative reduction of pathogens is sufficient to prevent ongoing chronic infections, for example, due to forming of biofilms. PMID:25705686

Agricultural pathogen decontamination technology-reducing the threat of infectious agent spread.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Betty, Rita G.; Bieker, Jill Marie; Tucker, Mark David

Outbreaks of infectious agricultural diseases, whether natural occurring or introduced intentionally, could have catastrophic impacts on the U.S. economy. Examples of such agricultural pathogens include foot and mouth disease (FMD), avian influenza (AI), citrus canker, wheat and soy rust, etc. Current approaches to mitigate the spread of agricultural pathogens include quarantine, development of vaccines for animal diseases, and development of pathogen resistant crop strains in the case of plant diseases. None of these approaches is rapid, and none address the potential persistence of the pathogen in the environment, which could lead to further spread of the agent and damage aftermore » quarantine is lifted. Pathogen spread in agricultural environments commonly occurs via transfer on agricultural equipment (transportation trailers, tractors, trucks, combines, etc.), having components made from a broad range of materials (galvanized and painted steel, rubber tires, glass and Plexiglas shields, etc), and under conditions of heavy organic load (mud, soil, feces, litter, etc). A key element of stemming the spread of an outbreak is to ensure complete inactivation of the pathogens in the agricultural environment and on the equipment used in those environments. Through the combination of enhanced agricultural pathogen decontamination chemistry and a validated inactivation verification methodology, important technologies for incorporation as components of a robust response capability will be enabled. Because of the potentially devastating economic impact that could result from the spread of infectious agricultural diseases, the proposed capability components will promote critical infrastructure protection and greater border and food supply security. We investigated and developed agricultural pathogen decontamination technologies to reduce the threat of infectious-agent spread, and thus enhance agricultural biosecurity. Specifically, enhanced detergency versions of the patented Sandia decontamination chemistry were developed and tested against a few surrogate pathogens under conditions of relatively heavy organic load. Tests were conducted on surfaces commonly found in agricultural environments. Wide spectrum decontamination efficacy, low corrosivity, and biodegradability issues were addressed in developing an enhanced detergency formulation. A method for rapid assessment of loss of pathogenic activity (inactivation) was also assessed. This enhanced technology will enable rapid assessment of contamination following an intentional event, and will also be extremely useful in routine assessment of agricultural environments. The primary effort during the second year was progress towards a demonstration of both decontamination and viral inactivation technologies of Foot and Mouth virus (FMDv) using the modified SNL chemistry developed through this project. Lab studies using a surrogate virus (bovine enterovirus) were conducted using DF200, modified DF200 chemistry, and decontaminants currently recommended for use in heavily loaded organic, agricultural environments (VirkonS, 10% bleach, sodium hydroxide and citric acid). Tests using actual FMD virus will be performed at the Department of Homeland Security's Plum Island facilities in the fall of 2005. Success and the insight gained from this project will lead to enhanced response capability, which will benefit agencies such as USDA, DHS, DOD, and the agricultural industry.« less

Addressing the Challenges of Pathogen Evolution on the World's Arable Crops.

PubMed

Burdon, Jeremy J; Zhan, Jiasui; Barrett, Luke G; Papaïx, Julien; Thrall, Peter H

2016-10-01

Advances in genomic and molecular technologies coupled with an increasing understanding of the fine structure of many resistance and infectivity genes, have opened up a new era of hope in controlling the many plant pathogens that continue to be a major source of loss in arable crops. Some new approaches are under consideration including the use of nonhost resistance and the targeting of critical developmental constraints. However, the major thrust of these genomic and molecular approaches is to enhance the identification of resistance genes, to increase their ease of manipulation through marker and gene editing technologies and to lock a range of resistance genes together in simply manipulable resistance gene cassettes. All these approaches essentially continue a strategy that assumes the ability to construct genetic-based resistance barriers that are insurmountable to target pathogens. Here we show how the recent advances in knowledge and marker technologies can be used to generate more durable disease resistance strategies that are based on broad evolutionary principles aimed at presenting pathogens with a shifting, landscape of fluctuating directional selection.

Inactivation of bacterial pathogenic load in compost against vermicompost of organic solid waste aiming to achieve sanitation goals: A review.

PubMed

Soobhany, Nuhaa; Mohee, Romeela; Garg, Vinod Kumar

2017-06-01

Waste management strategies for organic residues, such as composting and vermicomposting, have been implemented in some developed and developing countries to solve the problem of organic solid waste (OSW). Yet, these biological treatment technologies do not always result in good quality compost or vermicompost with regards to sanitation capacity owing to the presence of bacterial pathogenic substances in objectionable concentrations. The presence of pathogens in soil conditioners poses a potential health hazard and their occurrence is of particular significance in composts and/or vermicomposts produced from organic materials. Past and present researches demonstrated a high-degree of agreement that various pathogens survive after the composting of certain OSW but whether similar changes in bacterial pathogenic loads arise during vermitechnology has not been thoroughly elucidated. This review garners information regarding the status of various pathogenic bacteria which survived or diffused after the composting process compared to the status of these pathogens after the vermicomposting of OSW with the aim of achieving sanitation goals. This work is also indispensable for the specification of compost quality guidelines concerning pathogen loads which would be specific to treatment technology. It was hypothesized that vermicomposting process for OSW can be efficacious in sustaining the existence of pathogenic organisms most specifically; human pathogens under safety levels. In summary, earthworms can be regarded as a way of obliterating pathogenic bacteria from OSW in a manner equivalent to earthworm gut transit mechanism which classifies vermicomposting as a promising sanitation technique in comparison to composting processes. Copyright © 2017 Elsevier Ltd. All rights reserved.

A New Proof of Concept in Bacterial Reduction: Antimicrobial Action of Violet-Blue Light (405 nm) in Ex Vivo Stored Plasma

PubMed Central

Maclean, Michelle; Anderson, John G.; MacGregor, Scott J.; White, Tracy

2016-01-01

Bacterial contamination of injectable stored biological fluids such as blood plasma and platelet concentrates preserved in plasma at room temperature is a major health risk. Current pathogen reduction technologies (PRT) rely on the use of chemicals and/or ultraviolet light, which affects product quality and can be associated with adverse events in recipients. 405 nm violet-blue light is antibacterial without the use of photosensitizers and can be applied at levels safe for human exposure, making it of potential interest for decontamination of biological fluids such as plasma. As a pilot study to test whether 405 nm light is capable of inactivating bacteria in biological fluids, rabbit plasma and human plasma were seeded with bacteria and treated with a 405 nm light emitting diode (LED) exposure system (patent pending). Inactivation was achieved in all tested samples, ranging from low volumes to prebagged plasma. 99.9% reduction of low density bacterial populations (≤103 CFU mL−1), selected to represent typical “natural” contamination levels, was achieved using doses of 144 Jcm−2. The penetrability of 405 nm light, permitting decontamination of prebagged plasma, and the nonrequirement for photosensitizing agents provide a new proof of concept in bacterial reduction in biological fluids, especially injectable fluids relevant to transfusion medicine. PMID:27774337

Innovative Approaches to Improve Anti-Infective Vaccine Efficacy.

PubMed

Yeaman, Michael R; Hennessey, John P

2017-01-06

Safe and efficacious vaccines are arguably the most successful medical interventions of all time. Yet the ongoing discovery of new pathogens, along with emergence of antibiotic-resistant pathogens and a burgeoning population at risk of such infections, imposes unprecedented public health challenges. To meet these challenges, innovative strategies to discover and develop new or improved anti-infective vaccines are necessary. These approaches must intersect the most meaningful insights into protective immunity and advanced technologies with capabilities to deliver immunogens for optimal immune protection. This goal is considered through several recent advances in host-pathogen relationships, conceptual strides in vaccinology, and emerging technologies. Given a clear and growing risk of pandemic disease should the threat of infection go unmet, developing vaccines that optimize protective immunity against high-priority and antibiotic-resistant pathogens represents an urgent and unifying imperative.

Deep sequencing of evolving pathogen populations: applications, errors, and bioinformatic solutions

PubMed Central

2014-01-01

Deep sequencing harnesses the high throughput nature of next generation sequencing technologies to generate population samples, treating information contained in individual reads as meaningful. Here, we review applications of deep sequencing to pathogen evolution. Pioneering deep sequencing studies from the virology literature are discussed, such as whole genome Roche-454 sequencing analyses of the dynamics of the rapidly mutating pathogens hepatitis C virus and HIV. Extension of the deep sequencing approach to bacterial populations is then discussed, including the impacts of emerging sequencing technologies. While it is clear that deep sequencing has unprecedented potential for assessing the genetic structure and evolutionary history of pathogen populations, bioinformatic challenges remain. We summarise current approaches to overcoming these challenges, in particular methods for detecting low frequency variants in the context of sequencing error and reconstructing individual haplotypes from short reads. PMID:24428920

Modern technologies for improving cleaning and disinfection of environmental surfaces in hospitals.

PubMed

Boyce, John M

2016-01-01

Experts agree that careful cleaning and disinfection of environmental surfaces are essential elements of effective infection prevention programs. However, traditional manual cleaning and disinfection practices in hospitals are often suboptimal. This is often due in part to a variety of personnel issues that many Environmental Services departments encounter. Failure to follow manufacturer's recommendations for disinfectant use and lack of antimicrobial activity of some disinfectants against healthcare-associated pathogens may also affect the efficacy of disinfection practices. Improved hydrogen peroxide-based liquid surface disinfectants and a combination product containing peracetic acid and hydrogen peroxide are effective alternatives to disinfectants currently in widespread use, and electrolyzed water (hypochlorous acid) and cold atmospheric pressure plasma show potential for use in hospitals. Creating "self-disinfecting" surfaces by coating medical equipment with metals such as copper or silver, or applying liquid compounds that have persistent antimicrobial activity surfaces are additional strategies that require further investigation. Newer "no-touch" (automated) decontamination technologies include aerosol and vaporized hydrogen peroxide, mobile devices that emit continuous ultraviolet (UV-C) light, a pulsed-xenon UV light system, and use of high-intensity narrow-spectrum (405 nm) light. These "no-touch" technologies have been shown to reduce bacterial contamination of surfaces. A micro-condensation hydrogen peroxide system has been associated in multiple studies with reductions in healthcare-associated colonization or infection, while there is more limited evidence of infection reduction by the pulsed-xenon system. A recently completed prospective, randomized controlled trial of continuous UV-C light should help determine the extent to which this technology can reduce healthcare-associated colonization and infections. In conclusion, continued efforts to improve traditional manual disinfection of surfaces are needed. In addition, Environmental Services departments should consider the use of newer disinfectants and no-touch decontamination technologies to improve disinfection of surfaces in healthcare.

Evaluation of antimicrobial peptides as novel bactericidal agents for room temperature-stored platelets.

PubMed

Mohan, Ketha V K; Rao, Shilpakala Sainath; Atreya, Chintamani D

2010-01-01

A single cost-effective pathogen inactivation approach would help to improve the safety of our nation's blood supply. Several methods and technologies are currently being studied to help reduce bacterial contamination of blood components. There is clearly need for simple and easy-to-use pathogen inactivation techniques specific to plasma, platelets (PLTs), and red blood cells. In this report, we introduce a novel proof of concept: using known therapeutic antimicrobial peptides (AMPs) as bactericidal agents for room temperature-stored PLT concentrates (PCs). Nine synthetic AMPs, four from PLT microbicidal protein-derived peptides (PD1-4) and five Arg-Trp (RW) repeat peptides containing one to five repeats, were tested for bactericidal activity in plasma and PC samples spiked with Staphylococcus aureus, S. epidermidis, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Bacillus cereus. A 3-log reduction of viable bacteria was considered as the bactericidal activity of a given peptide. In both plasma alone and PCs, RW3 peptide demonstrated bactericidal activity against S. aureus, S. epidermidis, E. coli, P. aeruginosa, and K. pneumoniae; PD4 and RW2 against P. aeruginosa; and RW4 against K. pneumoniae. The activity of each of these four peptides against the remaining bacterial species in the test panel resulted in less than a 3-log reduction in the number of viable bacteria and hence considered ineffective. These findings suggest a new approach to improving the safety of blood components, demonstrating the potential usefulness of screening therapeutic AMPs against selected bacteria to identify suitable bactericidal agents for stored plasma, PCs, and other blood products.

From diagnostics to metagenomics: Applications of DNA-based tools in forest pathology

Treesearch

Amy L. Ross-Davis; Mee-Sook Kim; Jane E. Stewart; John W. Hanna; John D. Shaw; Ned B. Klopfenstein

2013-01-01

Advances in molecular technology provide an accessible set of tools to 1) help forest pathologists detect, identify, and monitor forest pathogens, 2) examine the evolutionary relationships and global distributions of forest pathogens and their hosts, 3) assess the diversity and structure of host and pathogen populations, and 4) evaluate the structure and function of...

40 CFR 503.10 - Applicability.

Code of Federal Regulations, 2011 CFR

2011-07-01

... pathogen requirements in § 503.32(a); and one of the vector attraction reduction requirements in § 503.33(b... of the vector attraction reduction requirements in § 503.33(b)(1) through (b)(8). (2) The Regional... requirements in § 503.32(a); and one of the vector attraction reduction requirements in § 503.33(b)(1) through...

Critical Low-Noise Technologies Being Developed for Engine Noise Reduction Systems Subproject

NASA Technical Reports Server (NTRS)

Grady, Joseph E.; Civinskas, Kestutis C.

2004-01-01

NASA's previous Advanced Subsonic Technology (AST) Noise Reduction Program delivered the initial technologies for meeting a 10-year goal of a 10-dB reduction in total aircraft system noise. Technology Readiness Levels achieved for the engine-noise-reduction technologies ranged from 4 (rig scale) to 6 (engine demonstration). The current Quiet Aircraft Technology (QAT) project is building on those AST accomplishments to achieve the additional noise reduction needed to meet the Aerospace Technology Enterprise's 10-year goal, again validated through a combination of laboratory rig and engine demonstration tests. In order to meet the Aerospace Technology Enterprise goal for future aircraft of a 50- reduction in the perceived noise level, reductions of 4 dB are needed in both fan and jet noise. The primary objectives of the Engine Noise Reduction Systems (ENRS) subproject are, therefore, to develop technologies to reduce both fan and jet noise by 4 dB, to demonstrate these technologies in engine tests, and to develop and experimentally validate Computational Aero Acoustics (CAA) computer codes that will improve our ability to predict engine noise.

Minimal heat treatments reduce Shiga toxin-producing Escherichia coli (STEC)and Salmonella on the surface of fresh beef

USDA-ARS?s Scientific Manuscript database

Washing and sanitizing agents have been effective in reducing bacterial populations and pathogen presence on carcasses. Thermal interventions consistently provide the greatest pathogen reductions and can be applied during slaughter in a number of different forms, either as a whole carcass wash, or t...

New wash aid T-128 improves efficacy of chlorine against cross contamination by bacterial pathogens in fresh-cut lettuce processing

USDA-ARS?s Scientific Manuscript database

Chlorinated water is widely used as the primary anti-microbial intervention during fresh-cut produce processing. Free chlorine in chlorinated water can provide effective reduction of potential contaminations by microbial pathogens, and, more importantly, effectively prevent cross contamination of p...

Assessment of the pathogenicity of cell-culture-adapted Newcastle disease virus strain Komarov.

PubMed

Visnuvinayagam, Sivam; Thangavel, K; Lalitha, N; Malmarugan, S; Sukumar, Kuppannan

2015-01-01

Newcastle disease vaccines hitherto in vogue are produced from embryonated chicken eggs. Egg-adapted mesogenic vaccines possess several drawbacks such as paralysis and mortality in 2-week-old chicks and reduced egg production in the egg-laying flock. Owing to these possible drawbacks, we attempted to reduce the vaccine virulence for safe vaccination by adapting the virus in a chicken embryo fibroblast cell culture (CEFCC) system. Eighteen passages were carried out by CEFCC, and the pathogenicity was assessed on the basis of the mean death time, intracerebral pathogenicity index, and intravenous pathogenicity index, at equal passage intervals. Although the reduction in virulence demonstrated with increasing passage levels in CEFCC was encouraging, 20% of the 2-week-old birds showed paralytic symptoms with the virus vaccine from the 18(th)(final) passage. Thus, a tissue-culture-adapted vaccine would demand a few more passages by CEFCC in order to achieve a complete reduction in virulence for use as a safe and effective vaccine, especially among younger chicks. Moreover, it can be safely administered even to unprimed 8-week-old birds.

Removal of contaminants and pathogens from secondary effluents using intermittent sand filters.

PubMed

Bali, Mahmoud; Gueddari, Moncef; Boukchina, Rachid

2011-01-01

Intermittent infiltration percolation of wastewater through unsaturated sand bed is an extensive treatment technique aimed at eliminating organic matter, oxidizing ammonium and removing pathogens. The main purpose of this study was to determine the depuration efficiencies of a sand filter to remove contaminants from secondary wastewater effluents. Elimination of pathogenic bacteria (total and faecal coliforms, streptococci) and their relationship with the filter depth were investigated. Results showed a high capacity of infiltration percolation process to treat secondary effluents. Total elimination of suspended solids was obtained. Mean removal rate of BOD(5) and COD was more than 97 and more than 81%, respectively. Other water quality parameters such as NH(4)-N, TKN and PO(4)-P showed significant reduction except NO(3)-N which increased significantly in the filtered water. Efficiency of pathogenic bacteria removal was shown to mainly depend on the filter depth. Average reductions of 2.35 log total coliforms, 2.47 log faecal coliforms and 2.11 log faecal streptococci were obtained. The experimental study has shown the influence of the temperature on the output purification of infiltration percolation process.

The oxygen reduction pathway and heat shock stress response are both required for Entamoeba histolytica pathogenicity.

PubMed

Olivos-García, Alfonso; Saavedra, Emma; Nequiz, Mario; Santos, Fabiola; Luis-García, Erika Rubí; Gudiño, Marco; Pérez-Tamayo, Ruy

2016-05-01

Several species belonging to the genus Entamoeba can colonize the mouth or the human gut; however, only Entamoeba histolytica is pathogenic to the host, causing the disease amoebiasis. This illness is responsible for one hundred thousand human deaths per year worldwide, affecting mainly underdeveloped countries. Throughout its entire life cycle and invasion of human tissues, the parasite is constantly subjected to stress conditions. Under in vitro culture, this microaerophilic parasite can tolerate up to 5 % oxygen concentrations; however, during tissue invasion the parasite has to cope with the higher oxygen content found in well-perfused tissues (4-14 %) and with reactive oxygen and nitrogen species derived from both host and parasite. In this work, the role of the amoebic oxygen reduction pathway (ORP) and heat shock response (HSP) are analyzed in relation to E. histolytica pathogenicity. The data suggest that in contrast with non-pathogenic E. dispar, the higher level of ORP and HSPs displayed by E. histolytica enables its survival in tissues by diminishing and detoxifying intracellular oxidants and repairing damaged proteins to allow metabolic fluxes, replication and immune evasion.

Edible apple film wraps containing plant antimicrobials inactivate foodborne pathogens on meat and poultry products.

PubMed

Ravishankar, Sadhana; Zhu, Libin; Olsen, Carl W; McHugh, Tara H; Friedman, Mendel

2009-10-01

Apple-based edible films containing plant antimicrobials were evaluated for their activity against pathogenic bacteria on meat and poultry products. Salmonella enterica or E. coli O157:H7 (10(7) CFU/g) cultures were surface inoculated on chicken breasts and Listeria monocytogenes (10(6) CFU/g) on ham. The inoculated products were then wrapped with edible films containing 3 concentrations (0.5%, 1.5%, and 3%) of cinnamaldehyde or carvacrol. Following incubation at either 23 or 4 degrees C for 72 h, samples were stomached in buffered peptone water, diluted, and plated for enumeration of survivors. The antimicrobial films exhibited concentration-dependent activities against the pathogens tested. At 23 degrees C on chicken breasts, films with 3% antimicrobials showed the highest reductions (4.3 to 6.8 log CFU/g) of both S. enterica and E. coli O157:H7. Films with 1.5% and 0.5% antimicrobials showed 2.4 to 4.3 and 1.6 to 2.8 log reductions, respectively. At 4 degrees C, carvacrol exhibited greater activity than did cinnamaldehyde. Films with 3%, 1.5%, and 0.5% carvacrol reduced the bacterial populations by about 3, 1.6 to 3, and 0.8 to 1 logs, respectively. Films with 3% and 1.5% cinnamaldehyde induced 1.2 to 2.8 and 1.2 to 1.3 log reductions, respectively. For L. monocytogenes on ham, carvacrol films induced greater reductions than did cinnamaldehyde films at all concentrations tested. In general, the reduction of L. monocytogenes on ham at 23 degrees C was greater than at 4 degrees C. Added antimicrobials had minor effects on physical properties of the films. The results suggest that the food industry and consumers could use these films as wrappings to control surface contamination by foodborne pathogenic microorganisms.

Evaluation of a rapid, quantitative real-time PCR method for enumeration of pathogenic Candida cells in water

USGS Publications Warehouse

Brinkman, Nichole E.; Haugland, Richard A.; Wymer, Larry J.; Byappanahalli, Muruleedhara N.; Whitman, Richard L.; Vesper, Stephen J.

2003-01-01

Quantitative PCR (QPCR) technology, incorporating fluorigenic 5′ nuclease (TaqMan) chemistry, was utilized for the specific detection and quantification of six pathogenic species of Candida (C. albicans, C. tropicalis, C. krusei, C. parapsilosis, C. glabrata and C. lusitaniae) in water. Known numbers of target cells were added to distilled and tap water samples, filtered, and disrupted directly on the membranes for recovery of DNA for QPCR analysis. The assay's sensitivities were between one and three cells per filter. The accuracy of the cell estimates was between 50 and 200% of their true value (95% confidence level). In similar tests with surface water samples, the presence of PCR inhibitory compounds necessitated further purification and/or dilution of the DNA extracts, with resultant reductions in sensitivity but generally not in quantitative accuracy. Analyses of a series of freshwater samples collected from a recreational beach showed positive correlations between the QPCR results and colony counts of the corresponding target species. Positive correlations were also seen between the cell quantities of the target Candida species detected in these analyses and colony counts of Enterococcus organisms. With a combined sample processing and analysis time of less than 4 h, this method shows great promise as a tool for rapidly assessing potential exposures to waterborne pathogenic Candida species from drinking and recreational waters and may have applications in the detection of fecal pollution.

Effectiveness of superheated steam for inactivation of Escherichia coli O157:H7, Salmonella Typhimurium, Salmonella Enteritidis phage type 30, and Listeria monocytogenes on almonds and pistachios.

PubMed

Ban, Ga-Hee; Kang, Dong-Hyun

2016-03-02

This study was undertaken to evaluate the effectiveness of superheated steam (SHS) on the inactivation of Escherichia coli O157:H7, Salmonella Typhimurium, Salmonella Enteritidis phage type (PT) 30 and Listeria monocytogenes on almonds and in-shell pistachios and to determine the effect of superheated steam heating on quality by measuring color and texture changes. Almonds and in-shell pistachios inoculated with four foodborne pathogens were treated with saturated steam (SS) at 100 °C and SHS at 125, 150, 175, and 200 °C for various times. Exposure of almonds and pistachios to SHS for 15 or 30s at 200 °C achieved >5l og reductions among all tested pathogens without causing significant changes in color values or texture parameters (P>0.05). For both almonds and pistachios, acid and peroxide values (PV) following SS and SHS treatment for up to 15s and 30s, respectively, were within the acceptable range (PV<1.0 meq/kg). These results show that thermal application of 200 °C SHS treatment for 15s and 30s did not affect the quality of almonds and pistachios, respectively. Therefore, SHS treatment is a very promising alternative technology for the tree nuts industry by improving inactivation of foodborne pathogens on almonds and pistachios while simultaneously reducing processing time. Copyright © 2016 Elsevier B.V. All rights reserved.

Efficient reduction of pathogenic and spoilage microorganisms from apple cider by combining microfiltration with UV treatment.

PubMed

Zhao, Dongjun; Barrientos, Jessie Usaga; Wang, Qing; Markland, Sarah M; Churey, John J; Padilla-Zakour, Olga I; Worobo, Randy W; Kniel, Kalmia E; Moraru, Carmen I

2015-04-01

Thermal pasteurization can achieve the U. S. Food and Drug Administration-required 5-log reduction of pathogenic Escherichia coli O157:H7 and Cryptosporidium parvum in apple juice and cider, but it can also negatively affect the nutritional and organoleptic properties of the treated products. In addition, thermal pasteurization is only marginally effective against the acidophilic, thermophilic, and spore-forming bacteria Alicyclobacillus spp., which is known to cause off-flavors in juice products. In this study, the efficiency of a combined microfiltration (MF) and UV process as a nonthermal treatment for the reduction of pathogenic and nonpathogenic E. coli, C. parvum, and Alicyclobacillus acidoterrestris from apple cider was investigated. MF was used to physically remove suspended solids and microorganisms from apple cider, thus enhancing the effectiveness of UV and allowing a lower UV dose to be used. MF, with ceramic membranes (pore sizes, 0.8 and 1.4 μm), was performed at a temperature of 10 °C and a transmembrane pressure of 155 kPa. The subsequent UV treatment was conducted using at a low UV dose of 1.75 mJ/cm(2). The combined MF and UV achieved more than a 5-log reduction of E. coli, C. parvum, and A. acidoterrestris. MF with the 0.8-μm pore size performed better than the 1.4-μm pore size on removal of E. coli and A. acidoterrestris. The developed nonthermal hurdle treatment has the potential to significantly reduce pathogens, as well as spores, yeasts, molds, and protozoa in apple cider, and thus help juice processors improve the safety and quality of their products.

Nitric Oxide in the Offensive Strategy of Fungal and Oomycete Plant Pathogens

PubMed Central

Arasimowicz-Jelonek, Magdalena; Floryszak-Wieczorek, Jolanta

2016-01-01

In the course of evolutionary changes pathogens have developed many invasion strategies, to which the host organisms responded with a broad range of defense reactions involving endogenous signaling molecules, such as nitric oxide (NO). There is evidence that pathogenic microorganisms, including two most important groups of eukaryotic plant pathogens, also acquired the ability to synthesize NO via non-unequivocally defined oxidative and/or reductive routes. Although the both kingdoms Chromista and Fungi are remarkably diverse, the experimental data clearly indicate that pathogen-derived NO is an important regulatory molecule controlling not only developmental processes, but also pathogen virulence and its survival in the host. An active control of mitigation or aggravation of nitrosative stress within host cells seems to be a key determinant for the successful invasion of plant pathogens representing different lifestyles and an effective mode of dispersion in various environmental niches. PMID:26973690

Electron beam inactivation of selected microbial pathogens and indicator organisms in aerobically and anaerobically digested sewage sludge.

PubMed

Praveen, Chandni; Jesudhasan, Palmy R; Reimers, Robert S; Pillai, Suresh D

2013-09-01

Microbial pathogens in municipal sewage sludges need to be inactivated prior to environmental disposal. The efficacy of high energy (10 MeV) e-beam irradiation to inactivate a variety of selected microbial pathogens and indicator organisms in aerobically and anaerobically digested sewage sludge was evaluated. Both bacterial and viral pathogens and indicator organisms are susceptible to e-beam irradiation. However, as expected there was a significant difference in their respective e-beam irradiation sensitivity. Somatic coliphages, bacterial endospores and enteric viruses were more resistant compared to bacterial pathogens. The current US EPA mandated 10 kGy minimum dose was capable of achieving significant reduction of both bacterial and viral pathogens. Somatic coliphages can be used as a microbial indicator for monitoring e-beam processes in terms of pathogen inactivation in sewage sludges. Copyright © 2013 Elsevier Ltd. All rights reserved.

Modern banking, collection, compatibility testing and storage of blood and blood components.

PubMed

Green, L; Allard, S; Cardigan, R

2015-01-01

The clinical practice of blood transfusion has changed considerably over the last few decades. The potential risk of transfusion transmissible diseases has directed efforts towards the production of safe and high quality blood. All transfusion services now operate in an environment of ever-increasing regulatory controls encompassing all aspects of blood collection, processing and storage. Stringent donor selection, identification of pathogens that can be transmitted through blood, and development of technologies that can enhance the quality of blood, have all led to a substantial reduction in potential risks and complications associated with blood transfusion. In this article, we will discuss the current standards required for the manufacture of blood, starting from blood collection, through processing and on to storage. © 2014 The Association of Anaesthetists of Great Britain and Ireland.

Biofiltration for stormwater harvesting: Comparison of Campylobacter spp. and Escherichia coli removal under normal and challenging operational conditions

NASA Astrophysics Data System (ADS)

Chandrasena, G. I.; Deletic, A.; McCarthy, D. T.

2016-06-01

Knowledge of pathogen removal in stormwater biofilters (also known as stormwater bioretention systems or rain gardens) has predominately been determined using bacterial indicators, and the removal of reference pathogens in these systems has rarely been investigated. Furthermore, current understanding of indicator bacteria removal in these systems is largely built upon laboratory-scale work. This paper examines whether indicator organism removal from urban stormwater using biofilters in laboratory settings are representative of the removal of pathogens in field conditions, by studying the removal of Escherichia coli (a typical indicator microorganism) and Campylobacter spp. (a typical reference pathogen) from urban stormwater by two established field-scale biofilters. It was found that E. coli log reduction was higher than that of Campylobacter spp. in both biofilters, and that there was no correlation between E. coli and Campylobacter spp. log removal performance. This confirms that E. coli behaves significantly differently to this reference pathogen, reinforcing that single organisms should not be employed to understand faecal microorganism removal in urban stormwater treatment systems. The average reduction in E. coli from only one of the tested biofilters was able to meet the log reduction targets suggested in the current Australian stormwater harvesting guidelines for irrigating sports fields and golf courses. The difference in the performance of the two biofilters is likely a result of a number of design and operational factors; the most important being that the biofilter that did not meet the guidelines was tested using extremely high influent volumes and microbial concentrations, and long antecedent dry weather periods. As such, the E. coli removal performances identified in this study confirmed laboratory findings that inflow concentration and antecedent dry period impact overall microbial removal. In general, this paper emphasizes the need for the validation of stormwater harvesting systems, namely, the testing of treatment systems under challenging operational conditions using multiple indicators and reference pathogens.

Reduction of Escherichia coli O157:H7 on produce by use of electrolyzed water under simulated food service operation conditions.

PubMed

Pangloli, Philipus; Hung, Yen-Con; Beuchat, Larry R; King, C Harold; Zhao, Zhi-Hui

2009-09-01

Treatment of fresh fruits and vegetables with electrolyzed water (EW) has been shown to kill or reduce foodborne pathogens. We evaluated the efficacy of EW in killing Escherichia coli O157:H7 on iceberg lettuce, cabbage, lemons, and tomatoes by using washing and/or chilling treatments simulating those followed in some food service kitchens. Greatest reduction levels on lettuce were achieved by sequentially washing with 14-A (amperage) acidic EW (AcEW) for 15 or 30 s followed by chilling in 16-A AcEW for 15 min. This procedure reduced the pathogen by 2.8 and 3.0 log CFU per leaf, respectively, whereas washing and chilling with tap water reduced the pathogen by 1.9 and 2.4 log CFU per leaf. Washing cabbage leaves for 15 or 30 s with tap water or 14-A AcEW reduced the pathogen by 2.0 and 3.0 log CFU per leaf and 2.5 to 3.0 log CFU per leaf, respectively. The pathogen was reduced by 4.7 log CFU per lemon by washing with 14-A AcEW and 4.1 and 4.5 log CFU per lemon by washing with tap water for 15 or 30 s. A reduction of 5.3 log CFU per lemon was achieved by washing with 14-A alkaline EW for 15 s prior to washing with 14-A AcEW for 15 s. Washing tomatoes with tap water or 14-A AcEW for 15 s reduced the pathogen by 6.4 and 7.9 log CFU per tomato, respectively. Application of AcEW using procedures mimicking food service operations should help minimize cross-contamination and reduce the risk of E. coli O157:H7 being present on produce at the time of consumption.

Plant pathogen nanodiagnostic techniques: forthcoming changes?

PubMed Central

Khiyami, Mohammad A.; Almoammar, Hassan; Awad, Yasser M.; Alghuthaymi, Mousa A.; Abd-Elsalam, Kamel A.

2014-01-01

Plant diseases are among the major factors limiting crop productivity. A first step towards managing a plant disease under greenhouse and field conditions is to correctly identify the pathogen. Current technologies, such as quantitative polymerase chain reaction (Q-PCR), require a relatively large amount of target tissue and rely on multiple assays to accurately identify distinct plant pathogens. The common disadvantage of the traditional diagnostic methods is that they are time consuming and lack high sensitivity. Consequently, developing low-cost methods to improve the accuracy and rapidity of plant pathogens diagnosis is needed. Nanotechnology, nano particles and quantum dots (QDs) have emerged as essential tools for fast detection of a particular biological marker with extreme accuracy. Biosensor, QDs, nanostructured platforms, nanoimaging and nanopore DNA sequencing tools have the potential to raise sensitivity, specificity and speed of the pathogen detection, facilitate high-throughput analysis, and to be used for high-quality monitoring and crop protection. Furthermore, nanodiagnostic kit equipment can easily and quickly detect potential serious plant pathogens, allowing experts to help farmers in the prevention of epidemic diseases. The current review deals with the application of nanotechnology for quicker, more cost-effective and precise diagnostic procedures of plant diseases. Such an accurate technology may help to design a proper integrated disease management system which may modify crop environments to adversely affect crop pathogens. PMID:26740775

Preliminary evaluation of pathogenic bacteria loading on organic Municipal Solid Waste compost and vermicompost.

PubMed

Soobhany, Nuhaa

2018-01-15

The use of composts or vermicomposts derived from organic fraction of Municipal Solid Waste (OFMSW) brought about certain disagreement in terms of high level of bacterial pathogens, thereby surpassing the legal restrictions. This preliminary study was undertaken to compare the evolution of pathogenic bacteria on OFMSW compost against vermicompost (generated by Eudrilus eugeniae) with promises of achieving sanitation goals. Analysis to quality data showed that OFMSW vermicomposting caused a moderately higher reduction in total coliforms in contrast to composting. E. coli in OFMSW composts was found to be in the range of 4.72-4.96 log 10  CFU g -1 whilst on a clear contrary, E. coli was undetectable in the final vermicomposts (6.01-6.14 logs of reduction) which might be explained by the involvement of the digestive processes in worms' guts. Both OFMSW composts and vermicomposts generated Salmonella-free products which were acceptable for agricultural usage and soil improvement. In comparison to compost, the analysis of this research indicated that earthworm activity can effectively destroy bacterial pathogenic load in OFMSW vermicomposts. But still, this study necessitates extra research in order to comprehend the factors that direct pathogenic bacteria in vermicomposting and earthworm-free decomposition systems. Copyright © 2017 Elsevier Ltd. All rights reserved.

Biological and Physicochemical Wastewater Treatment Processes Reduce the Prevalence of Virulent Escherichia coli

PubMed Central

Biswal, Basanta Kumar; Mazza, Alberto; Masson, Luke; Gehr, Ronald

2013-01-01

Effluents discharged from wastewater treatment plants are possible sources of pathogenic bacteria, including Escherichia coli, in the freshwater environment, and determining the possible selection of pathogens is important. This study evaluated the impact of activated sludge and physicochemical wastewater treatment processes on the prevalence of potentially virulent E. coli. A total of 719 E. coli isolates collected from four municipal plants in Québec before and after treatment were characterized by using a customized DNA microarray to determine the impact of treatment processes on the frequency of specific pathotypes and virulence genes. The percentages of potentially pathogenic E. coli isolates in the plant influents varied between 26 and 51%, and in the effluents, the percentages were 14 to 31%, for a reduction observed at all plants ranging between 14 and 45%. Pathotypes associated with extraintestinal pathogenic E. coli (ExPEC) were the most abundant at three of the four plants and represented 24% of all isolates, while intestinal pathogenic E. coli pathotypes (IPEC) represented 10% of the isolates. At the plant where ExPEC isolates were not the most abundant, a large number of isolates were classified as both ExPEC and IPEC; overall, 6% of the isolates were classified in both groups, with the majority being from the same plant. The reduction of the proportion of pathogenic E. coli could not be explained by the preferential loss of one virulence gene or one type of virulence factor; however, the quinolone resistance gene (qnrS) appears to enhance the loss of virulence genes, suggesting a mechanism involving the loss of pathogenicity islands. PMID:23160132

Meta-analysis of the Effects of Sanitizing Treatments on Salmonella, Escherichia coli O157:H7, and Listeria monocytogenes Inactivation in Fresh Produce

PubMed Central

Prado-Silva, Leonardo; Cadavez, Vasco; Gonzales-Barron, Ursula; Rezende, Ana Carolina B.

2015-01-01

The aim of this study was to perform a meta-analysis of the effects of sanitizing treatments of fresh produce on Salmonella spp., Escherichia coli O157:H7, and Listeria monocytogenes. From 55 primary studies found to report on such effects, 40 were selected based on specific criteria, leading to more than 1,000 data on mean log reductions of these three bacterial pathogens impairing the safety of fresh produce. Data were partitioned to build three meta-analytical models that could allow the assessment of differences in mean log reductions among pathogens, fresh produce, and sanitizers. Moderating variables assessed in the meta-analytical models included type of fresh produce, type of sanitizer, concentration, and treatment time and temperature. Further, a proposal was done to classify the sanitizers according to bactericidal efficacy by means of a meta-analytical dendrogram. The results indicated that both time and temperature significantly affected the mean log reductions of the sanitizing treatment (P < 0.0001). In general, sanitizer treatments led to lower mean log reductions when applied to leafy greens (for example, 0.68 log reductions [0.00 to 1.37] achieved in lettuce) compared to other, nonleafy vegetables (for example, 3.04 mean log reductions [2.32 to 3.76] obtained for carrots). Among the pathogens, E. coli O157:H7 was more resistant to ozone (1.6 mean log reductions), while L. monocytogenes and Salmonella presented high resistance to organic acids, such as citric acid, acetic acid, and lactic acid (∼3.0 mean log reductions). With regard to the sanitizers, it has been found that slightly acidic electrolyzed water, acidified sodium chlorite, and the gaseous chlorine dioxide clustered together, indicating that they possessed the strongest bactericidal effect. The results reported seem to be an important achievement for advancing the global understanding of the effectiveness of sanitizers for microbial safety of fresh produce. PMID:26362982

FNR Regulates the Expression of Important Virulence Factors Contributing to the Pathogenicity of Avian Pathogenic Escherichia coli

PubMed Central

Barbieri, Nicolle L.; Vande Vorde, Jessica A.; Baker, Alison R.; Horn, Fabiana; Li, Ganwu; Logue, Catherine M.; Nolan, Lisa K.

2017-01-01

Avian pathogenic Escherichia coli (APEC) is the etiologic agent of colibacillosis, an important cause of morbidity and mortality in poultry. Though, many virulence factors associated with APEC pathogenicity are known, their regulation remains unclear. FNR (fumarate and nitrate reduction) is a well-known global regulator that works as an oxygen sensor and has previously been described as a virulence regulator in bacterial pathogens. The goal of this study was to examine the role of FNR in the regulation of APEC virulence factors, such as Type I fimbriae, and processes such as adherence and invasion, type VI secretion, survival during oxidative stress, and growth in iron-restricted environments. To accomplish this goal, APEC O1, a well-characterized, highly virulent, and fully sequenced strain of APEC harboring multiple virulence mechanisms, some of which are plasmid-linked, was compared to its FNR mutant for expression of various virulence traits. Deletion of FNR was found to affect APEC O1's adherence, invasion and expression of ompT, a plasmid-encoded outer membrane protein, type I fimbriae, and aatA, encoding an autotransporter. Indeed, the fnr− mutant showed an 8-fold reduction in expression of type I fimbriae and a highly significant (P < 0.0001) reduction in expression of fimA, ompT (plasmid-borne), and aatA. FNR was also found to regulate expression of the type VI secretion system, affecting the expression of vgrG. Further, FNR was found to be important to APEC O1's growth in iron-deficient media and survival during oxidative stress with the mutant showing a 4-fold decrease in tolerance to oxidative stress, as compared to the wild type. Thus, our results suggest that FNR functions as an important regulator of APEC virulence. PMID:28690981

Efficacy of antimicrobials for the disinfection of pathogen contaminated green bell pepper and of consumer cleaning methods for the decontamination of knives.

PubMed

Perez, Keila L; Lucia, Lisa M; Cisneros-Zevallos, Luis; Castillo, Alejandro; Taylor, T Matthew

2012-05-01

While there is strong focus on eliminating pathogens from produce at a commercial level, consumers can employ simple methods to achieve additional pathogen reductions in the domestic kitchen. To determine the ability of antimicrobials to decontaminate peppers, samples of green bell pepper were inoculated with Salmonella enterica and Escherichia coli O157:H7 and then immersed in 3% (v/v) hydrogen peroxide (H₂O₂), 2.5% (v/v) acetic acid (AA), 70% (v/v) ethyl alcohol (EtOH), or sterile distilled water (SDW). The potential for transfer of pathogens from contaminated peppers to other non-contaminated produce items, and the effect of knife disinfection in preventing this cross contamination, were also tested. Knife disinfection procedures were evaluated by chopping inoculated peppers into 1 cm² pieces with kitchen knives. Experimental knives were then treated by either no treatment (control), wiping with a dry sterile cotton towel, rinsing under running warm water for 5 or 10s, or applying a 1% (v/v) lauryl sulfate-based detergent solution followed by rinsing with warm running water for 10s. Following disinfection treatment, knives were used to slice cucumbers. Exposure to H₂O₂ for 5 min and EtOH for 1 min resulted in reductions of 1.3±0.3 log₁₀ CFU/cm² for both pathogens. A 5 min exposure to AA resulted in a reduction of S. enterica of 1.0±0.7 log₁₀ CFU/cm² and E. coli of 0.7±0.8 log₁₀ CFU/cm². No differences (p ≥ 0.05) were found between numbers of pathogens on knives and numbers of pathogens transferred to cucumber slices, suggesting that organisms remaining on knife surfaces were transferred to cucumbers during slicing. Findings suggest that EtOH and H₂O₂ may be effective antimicrobials for in-home decontamination of peppers, and that use of detergent and warm water is effective for decontamination of implements used during meal preparation. Published by Elsevier B.V.

Fluorescence imaging host pathogen interactions: fifteen years benefit of hindsight….

PubMed

Aulner, Nathalie; Danckaert, Anne; Fernandes, Julien; Nicola, Marie-Anne; Roux, Pascal; Salles, Audrey; Tinevez, Jean-Yves; Shorte, Spencer L

2018-03-19

We consider in review current state-of-the-art fluorescence microscopy for investigating the host-pathogen interface. Our perspective is honed from years with literally thousands of microbiologists using the variety of imaging technologies available within our dedicated BSL2/BSL3 optical imaging research service facilities at the Institut Pasteur Paris founded from scratch in 2001. During fifteen years learning from the success and failures of introducing different fluorescence imaging technologies, methods, and technical development strategies we provide here a synopsis review of our experience to date and a synthesis of how we see the future in perspective for fluorescence imaging at the host-pathogen interface. Copyright © 2018. Published by Elsevier Ltd.

Selective depletion of plasma prekallikrein or coagulation factor XII inhibits thrombosis in mice without increased risk of bleeding.

PubMed

Revenko, Alexey S; Gao, Dacao; Crosby, Jeff R; Bhattacharjee, Gourab; Zhao, Chenguang; May, Chris; Gailani, David; Monia, Brett P; MacLeod, A Robert

2011-11-10

Recent studies indicate that the plasma contact system plays an important role in thrombosis, despite being dispensable for hemostasis. For example, mice deficient in coagulation factor XII (fXII) are protected from arterial thrombosis and cerebral ischemia-reperfusion injury. We demonstrate that selective reduction of prekallikrein (PKK), another member of the contact system, using antisense oligonucleotide (ASO) technology results in an antithrombotic phenotype in mice. The effects of PKK deficiency were compared with those of fXII deficiency produced by specific ASO-mediated reduction of fXII. Mice with reduced PKK had ∼ 3-fold higher plasma levels of fXII, and reduced levels of fXIIa-serpin complexes, consistent with fXII being a substrate for activated PKK in vivo. PKK or fXII deficiency reduced thrombus formation in both arterial and venous thrombosis models, without an apparent effect on hemostasis. The amount of reduction of PKK and fXII required to produce an antithrombotic effect differed between venous and arterial models, suggesting that these factors may regulate thrombus formation by distinct mechanisms. Our results support the concept that fXII and PKK play important and perhaps nonredundant roles in pathogenic thrombus propagation, and highlight a novel, specific and safe pharmaceutical approach to target these contact system proteases.

Selective depletion of plasma prekallikrein or coagulation factor XII inhibits thrombosis in mice without increased risk of bleeding

PubMed Central

Revenko, Alexey S.; Gao, Dacao; Crosby, Jeff R.; Bhattacharjee, Gourab; Zhao, Chenguang; May, Chris; Gailani, David; Monia, Brett P.

2011-01-01

Recent studies indicate that the plasma contact system plays an important role in thrombosis, despite being dispensable for hemostasis. For example, mice deficient in coagulation factor XII (fXII) are protected from arterial thrombosis and cerebral ischemia-reperfusion injury. We demonstrate that selective reduction of prekallikrein (PKK), another member of the contact system, using antisense oligonucleotide (ASO) technology results in an antithrombotic phenotype in mice. The effects of PKK deficiency were compared with those of fXII deficiency produced by specific ASO-mediated reduction of fXII. Mice with reduced PKK had ∼ 3-fold higher plasma levels of fXII, and reduced levels of fXIIa-serpin complexes, consistent with fXII being a substrate for activated PKK in vivo. PKK or fXII deficiency reduced thrombus formation in both arterial and venous thrombosis models, without an apparent effect on hemostasis. The amount of reduction of PKK and fXII required to produce an antithrombotic effect differed between venous and arterial models, suggesting that these factors may regulate thrombus formation by distinct mechanisms. Our results support the concept that fXII and PKK play important and perhaps nonredundant roles in pathogenic thrombus propagation, and highlight a novel, specific and safe pharmaceutical approach to target these contact system proteases. PMID:21821705

Visualization of Host-Polerovirus Interaction Topologies Using Protein Interaction Reporter Technology.

PubMed

DeBlasio, Stacy L; Chavez, Juan D; Alexander, Mariko M; Ramsey, John; Eng, Jimmy K; Mahoney, Jaclyn; Gray, Stewart M; Bruce, James E; Cilia, Michelle

2016-02-15

Demonstrating direct interactions between host and virus proteins during infection is a major goal and challenge for the field of virology. Most protein interactions are not binary or easily amenable to structural determination. Using infectious preparations of a polerovirus (Potato leafroll virus [PLRV]) and protein interaction reporter (PIR), a revolutionary technology that couples a mass spectrometric-cleavable chemical cross-linker with high-resolution mass spectrometry, we provide the first report of a host-pathogen protein interaction network that includes data-derived, topological features for every cross-linked site that was identified. We show that PLRV virions have hot spots of protein interaction and multifunctional surface topologies, revealing how these plant viruses maximize their use of binding interfaces. Modeling data, guided by cross-linking constraints, suggest asymmetric packing of the major capsid protein in the virion, which supports previous epitope mapping studies. Protein interaction topologies are conserved with other species in the Luteoviridae and with unrelated viruses in the Herpesviridae and Adenoviridae. Functional analysis of three PLRV-interacting host proteins in planta using a reverse-genetics approach revealed a complex, molecular tug-of-war between host and virus. Structural mimicry and diversifying selection-hallmarks of host-pathogen interactions-were identified within host and viral binding interfaces predicted by our models. These results illuminate the functional diversity of the PLRV-host protein interaction network and demonstrate the usefulness of PIR technology for precision mapping of functional host-pathogen protein interaction topologies. The exterior shape of a plant virus and its interacting host and insect vector proteins determine whether a virus will be transmitted by an insect or infect a specific host. Gaining this information is difficult and requires years of experimentation. We used protein interaction reporter (PIR) technology to illustrate how viruses exploit host proteins during plant infection. PIR technology enabled our team to precisely describe the sites of functional virus-virus, virus-host, and host-host protein interactions using a mass spectrometry analysis that takes just a few hours. Applications of PIR technology in host-pathogen interactions will enable researchers studying recalcitrant pathogens, such as animal pathogens where host proteins are incorporated directly into the infectious agents, to investigate how proteins interact during infection and transmission as well as develop new tools for interdiction and therapy. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Visualization of Host-Polerovirus Interaction Topologies Using Protein Interaction Reporter Technology

PubMed Central

DeBlasio, Stacy L.; Chavez, Juan D.; Alexander, Mariko M.; Ramsey, John; Eng, Jimmy K.; Mahoney, Jaclyn; Gray, Stewart M.; Bruce, James E.

2015-01-01

ABSTRACT Demonstrating direct interactions between host and virus proteins during infection is a major goal and challenge for the field of virology. Most protein interactions are not binary or easily amenable to structural determination. Using infectious preparations of a polerovirus (Potato leafroll virus [PLRV]) and protein interaction reporter (PIR), a revolutionary technology that couples a mass spectrometric-cleavable chemical cross-linker with high-resolution mass spectrometry, we provide the first report of a host-pathogen protein interaction network that includes data-derived, topological features for every cross-linked site that was identified. We show that PLRV virions have hot spots of protein interaction and multifunctional surface topologies, revealing how these plant viruses maximize their use of binding interfaces. Modeling data, guided by cross-linking constraints, suggest asymmetric packing of the major capsid protein in the virion, which supports previous epitope mapping studies. Protein interaction topologies are conserved with other species in the Luteoviridae and with unrelated viruses in the Herpesviridae and Adenoviridae. Functional analysis of three PLRV-interacting host proteins in planta using a reverse-genetics approach revealed a complex, molecular tug-of-war between host and virus. Structural mimicry and diversifying selection—hallmarks of host-pathogen interactions—were identified within host and viral binding interfaces predicted by our models. These results illuminate the functional diversity of the PLRV-host protein interaction network and demonstrate the usefulness of PIR technology for precision mapping of functional host-pathogen protein interaction topologies. IMPORTANCE The exterior shape of a plant virus and its interacting host and insect vector proteins determine whether a virus will be transmitted by an insect or infect a specific host. Gaining this information is difficult and requires years of experimentation. We used protein interaction reporter (PIR) technology to illustrate how viruses exploit host proteins during plant infection. PIR technology enabled our team to precisely describe the sites of functional virus-virus, virus-host, and host-host protein interactions using a mass spectrometry analysis that takes just a few hours. Applications of PIR technology in host-pathogen interactions will enable researchers studying recalcitrant pathogens, such as animal pathogens where host proteins are incorporated directly into the infectious agents, to investigate how proteins interact during infection and transmission as well as develop new tools for interdiction and therapy. PMID:26656710

Estimation of norovirus infection risks to consumers of wastewater-irrigated food crops eaten raw.

PubMed

Mara, Duncan; Sleigh, Andrew

2010-03-01

A quantitative microbial risk analysis-Monte Carlo method was used to estimate norovirus infection risks to consumers of wastewater-irrigated lettuce. Using the same assumptions as used in the 2006 WHO guidelines for the safe use of wastewater in agriculture, a norovirus reduction of 6 log units was required to achieve a norovirus infection risk of approximately 10(-3) per person per year (pppy), but for a lower consumption of lettuce (40-48 g per week vs. 350 g per week) the required reduction was 5 log units. If the tolerable additional disease burden is increased from a DALY (disability-adjusted life year) loss of 10(-6) pppy (the value used in the WHO guidelines) to 10(-5) pppy, the required pathogen reduction is one order of magnitude lower. Reductions of 4-6 log units can be achieved by very simple partial treatment (principally settling to achieve a 1-log unit reduction) supplemented by very reliable post-treatment health-protection control measures such as pathogen die-off (1-2 log units), produce washing in cold water (1 log unit) and produce disinfection (3 log units).

Small-scale shifting mosaics of two dominant grassland species: the possible role of soil-borne pathogens.

PubMed

Olff, H; Hoorens, B; de Goede, R G M; van der Putten, W H; Gleichman, J M

2000-10-01

We analyzed the dynamics of dominant plant species in a grazed grassland over 17 years, and investigated whether local shifts in these dominant species, leading to vegetation mosaics, could be attributed to interactions between plants and soil-borne pathogens. We found that Festuca rubra and Carex arenaria locally alternated in abundance, with different sites close together behaving out of phase, resulting in a shifting mosaic. The net effect of killing all soil biota on the growth of these two species was investigated in a greenhouse experiment using gamma radiation, controlling for possible effects of sterilization on soil chemistry. Both plant species showed a strong net positive response to soil sterilization, indicating that pathogens (e.g., nematodes, pathogenic fungi) outweighed the effect of mutualists (e.g., mycorrhizae). This positive growth response towards soil sterilization appeared not be due to effects of sterilization on soil chemistry. Growth of Carex was strongly reduced by soil-borne pathogens (86% reduction relative to its growth on sterilized soil) on soil from a site where this species decreased during the last decade (and Festuca increased), while it was reduced much less (50%) on soil from a nearby site where it increased in abundance during the last decade. Similarly, Festuca was reduced more (67%) on soil from the site where it decreased (and Carex increased) than on soil from the site where it increased (55%, the site where Carex decreased). Plant-feeding nematodes showed high small-scale variation in densities, and we related this variation to the observed growth reductions in both plant species. Carex growth on unsterilized soil was significantly more reduced at higher densities of plant-feeding nematodes, while the growth reduction in Festuca was independent of plant-feeding nematode densities. At high plant-feeding nematode densities, growth of Carex was reduced more than Festuca, while at low nematode densities the opposite was found. Each plant species thus seems to be affected by different (groups of) soil-borne pathogens. The resulting interaction web of plants and soil-borne pathogens is discussed. We hypothesize that soil disturbances by digging ants and rabbits may explain the small-scale variation in nematode densities, by locally providing "fresh" sand. We conclude that soil-borne pathogens may contribute to plant diversity and spatial mosaics of plants in grasslands.

Effect of temperature on chlorine dioxide inactivation of Escherichia coli O157:H7, Salmonella typhimurium, and Listeria monocytogenes on spinach, tomatoes, stainless steel, and glass surfaces.

PubMed

Park, Sang-Hyun; Kang, Dong-Hyun

2018-06-20

The objective of this study was to evaluate how treatment temperature influences the solubility of ClO 2 gas and the antimicrobial effect of ClO 2 gas against Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes on produce and food contact surfaces. Produce and food contact surfaces inoculated with a combined culture cocktail of three strains each of the three foodborne pathogens were processed in a treatment chamber with 20 ppmv ClO 2 gas at 15 or 25 °C under the same conditions of absolute humidity (11.2-12.3 g/m 3 ) for up to 30 min. As treatment time increased, ClO 2 gas treatment at 15 °C caused significantly more (p < 0.05) inactivation of the three pathogens than treatment at 25 °C. ClO 2 gas treatment at 25 °C for 30 min resulted in 1.15 to 1.54, 1.53 to 1.88, and 1.00 to 1.78 log reductions of the three pathogens on spinach leaves, tomatoes, and stainless steel No.4, respectively. ClO 2 gas treatment at 15 °C for 30 min caused 2.53 to 2.88, 2.82 to 3.23, and 2.37 to 3.03 log reductions of the three pathogens on spinach leaves, tomatoes, and stainless steel No.4, respectively. Treatment with ClO 2 gas at 25 °C for 20 min resulted in 1.88 to 2.31 log reductions of the three pathogens on glass while >5.91 to 6.82 log reductions of these pathogens occurred after 20 min when treated at 15 °C. Residual ClO 2 levels after gas treatment at 15 °C were significantly (p < 0.05) higher than those at 25 °C. The results of this study can help the food processing industry establish optimum ClO 2 gas treatment conditions for maximizing the antimicrobial efficacy of ClO 2 gas. Published by Elsevier B.V.

Prudent Use of Antimicrobials in Exotic Animal Medicine.

PubMed

Broens, Els M; van Geijlswijk, Ingeborg M

2018-05-01

Reduction of antimicrobial use can result in reduction of resistance in commensal bacteria. In exotic animals, information on use of antimicrobials and resistance in commensals and pathogens is scarce. However, use of antimicrobials listed as critically important antimicrobials for human medicine seems high in exotic animals. Ideally, the selection of a therapy should be based on an accurate diagnosis and antimicrobial susceptibility testing. When prescribing antimicrobials based on empiricism, knowledge of the most common pathogens causing specific infections and the antimicrobial spectrum of antimicrobial agents is indispensable. Implementing antimicrobial stewardship promotes the prudent use of antimicrobials in exotic animals. Copyright © 2018 Elsevier Inc. All rights reserved.

Research on the application in disaster reduction for using cloud computing technology

NASA Astrophysics Data System (ADS)

Tao, Liang; Fan, Yida; Wang, Xingling

Cloud Computing technology has been rapidly applied in different domains recently, promotes the progress of the domain's informatization. Based on the analysis of the state of application requirement in disaster reduction and combining the characteristics of Cloud Computing technology, we present the research on the application of Cloud Computing technology in disaster reduction. First of all, we give the architecture of disaster reduction cloud, which consists of disaster reduction infrastructure as a service (IAAS), disaster reduction cloud application platform as a service (PAAS) and disaster reduction software as a service (SAAS). Secondly, we talk about the standard system of disaster reduction in five aspects. Thirdly, we indicate the security system of disaster reduction cloud. Finally, we draw a conclusion the use of cloud computing technology will help us to solve the problems for disaster reduction and promote the development of disaster reduction.

Subcontinental impacts of an invasive tree disease on forest structure and dynamics

Treesearch

Jeffrey R. Garnas; Matthew P. Ayres; Andrew M. Liebhold; Celia. Evans

2011-01-01

Introduced pests and pathogens are a major source of disturbance to ecosystems world-wide. The famous examples have produced dramatic reductions in host abundance, including virtual extirpation, but most introductions have more subtle impacts that are hard to quantify but are potentially at least as important due to the pathogens' effects on host reproduction,...

Risk reduction modeling of high pathogenicity avian influenza virus titers in non-pasteurized liquid egg obtained from infected but undetected chicken flocks

USDA-ARS?s Scientific Manuscript database

Control of highly pathogenic avian influenza (HPAI) has traditionally involved the establishment of disease containment zones, where poultry products are only permitted to move from within a containment area under permit. Non-pasteurized liquid egg (NPLE) is one such commodity for which movements ma...

Hitchhiker's guide to multi-dimensional plant pathology.

PubMed

Saunders, Diane G O

2015-02-01

Filamentous pathogens pose a substantial threat to global food security. One central question in plant pathology is how pathogens cause infection and manage to evade or suppress plant immunity to promote disease. With many technological advances over the past decade, including DNA sequencing technology, an array of new tools has become embedded within the toolbox of next-generation plant pathologists. By employing a multidisciplinary approach plant pathologists can fully leverage these technical advances to answer key questions in plant pathology, aimed at achieving global food security. This review discusses the impact of: cell biology and genetics on progressing our understanding of infection structure formation on the leaf surface; biochemical and molecular analysis to study how pathogens subdue plant immunity and manipulate plant processes through effectors; genomics and DNA sequencing technologies on all areas of plant pathology; and new forms of collaboration on accelerating exploitation of big data. As we embark on the next phase in plant pathology, the integration of systems biology promises to provide a holistic perspective of plant–pathogen interactions from big data and only once we fully appreciate these complexities can we design truly sustainable solutions to preserve our resources.

PATHOGEN EQUIVALENCY COMMITTEE (PEC)

EPA Science Inventory

The U.S. Environmental Protection Agency created the PEC in 1985 to make recommendations to EPA and State managers on the equivalency of unproven sewage sludge disinfection technologies/processes to either a Process to Significantly Reduce Pathogens (PSRP) or a Process to Further...

CHARACTERIZING AND MITIGATING PATHOGENIC ORGANISMS RELATED TO CAFOS

EPA Science Inventory

CHARACTERIZING AND MITIGATING PATHOGENIC ORGANISMS RELATED TO CAFOs John Haines and Shane Rogers NRMRL Science Questions MYP Science Ouestion: What BMP treatment systems and restoration technologies are most effective options for watershed management? For mixed land use wa...

Evaluation of the Advanced Subsonic Technology Program Noise Reduction Benefits

NASA Technical Reports Server (NTRS)

Golub, Robert A.; Rawls, John W., Jr.; Russell, James W.

2005-01-01

This report presents a detailed evaluation of the aircraft noise reduction technology concepts developed during the course of the NASA/FAA Advanced Subsonic Technology (AST) Noise Reduction Program. In 1992, NASA and the FAA initiated a cosponsored, multi-year program with the U.S. aircraft industry focused on achieving significant advances in aircraft noise reduction. The program achieved success through a systematic development and validation of noise reduction technology. Using the NASA Aircraft Noise Prediction Program, the noise reduction benefit of the technologies that reached a NASA technology readiness level of 5 or 6 were applied to each of four classes of aircraft which included a large four engine aircraft, a large twin engine aircraft, a small twin engine aircraft and a business jet. Total aircraft noise reductions resulting from the implementation of the appropriate technologies for each class of aircraft are presented and compared to the AST program goals.

Alternative Fuels Data Center: Heavy-Duty Truck Idle Reduction Technologies

Science.gov Websites

reduction technologies. Both DOE and the U.S. Environmental Protection Agency (EPA) provide information Heavy-Duty Truck Idle Reduction Technologies to someone by E-mail Share Alternative Fuels Data Center: Heavy-Duty Truck Idle Reduction Technologies on Facebook Tweet about Alternative Fuels Data

The impact of "omic" and imaging technologies on assessing the host immune response to biodefence agents.

PubMed

Tree, Julia A; Flick-Smith, Helen; Elmore, Michael J; Rowland, Caroline A

2014-01-01

Understanding the interactions between host and pathogen is important for the development and assessment of medical countermeasures to infectious agents, including potential biodefence pathogens such as Bacillus anthracis, Ebola virus, and Francisella tularensis. This review focuses on technological advances which allow this interaction to be studied in much greater detail. Namely, the use of "omic" technologies (next generation sequencing, DNA, and protein microarrays) for dissecting the underlying host response to infection at the molecular level; optical imaging techniques (flow cytometry and fluorescence microscopy) for assessing cellular responses to infection; and biophotonic imaging for visualising the infectious disease process. All of these technologies hold great promise for important breakthroughs in the rational development of vaccines and therapeutics for biodefence agents.

Artificially designed pathogens - a diagnostic option for future military deployments.

PubMed

Zautner, Andreas E; Masanta, Wycliffe O; Hinz, Rebecca; Hagen, Ralf Matthias; Frickmann, Hagen

2015-01-01

Diagnostic microbial isolates of bio-safety levels 3 and 4 are difficult to handle in medical field camps under military deployment settings. International transport of such isolates is challenging due to restrictions by the International Air Transport Association. An alternative option might be inactivation and sequencing of the pathogen at the deployment site with subsequent sequence-based revitalization in well-equipped laboratories in the home country for further scientific assessment. A literature review was written based on a PubMed search. First described for poliovirus in 2002, de novo synthesis of pathogens based on their sequence information has become a well-established procedure in science. Successful syntheses have been demonstrated for both viruses and prokaryotes. However, the technology is not yet available for routine diagnostic purposes. Due to the potential utility of diagnostic sequencing and sequence-based de novo synthesis of pathogens, it seems worthwhile to establish the technology for diagnostic purposes over the intermediate term. This is particularly true for resource-restricted deployment settings, where safe handling of harmful pathogens cannot always be guaranteed.

Improving Pathogen Reduction by Chlorine Wash Prior to Cutting in Fresh-Cut Processing

USDA-ARS?s Scientific Manuscript database

Introduction: Currently, most fresh-cut processing facilities in the United States use chlorinated water or other sanitizer solutions for microbial reduction after lettuce is cut. Freshly cut lettuce releases significant amounts of organic matter that negatively impacts the effectiveness of chlorine...

Microfluidic devices for sample preparation and rapid detection of foodborne pathogens.

PubMed

Kant, Krishna; Shahbazi, Mohammad-Ali; Dave, Vivek Priy; Ngo, Tien Anh; Chidambara, Vinayaka Aaydha; Than, Linh Quyen; Bang, Dang Duong; Wolff, Anders

2018-03-10

Rapid detection of foodborne pathogens at an early stage is imperative for preventing the outbreak of foodborne diseases, known as serious threats to human health. Conventional bacterial culturing methods for foodborne pathogen detection are time consuming, laborious, and with poor pathogen diagnosis competences. This has prompted researchers to call the current status of detection approaches into question and leverage new technologies for superior pathogen sensing outcomes. Novel strategies mainly rely on incorporating all the steps from sample preparation to detection in miniaturized devices for online monitoring of pathogens with high accuracy and sensitivity in a time-saving and cost effective manner. Lab on chip is a blooming area in diagnosis, which exploits different mechanical and biological techniques to detect very low concentrations of pathogens in food samples. This is achieved through streamlining the sample handling and concentrating procedures, which will subsequently reduce human errors and enhance the accuracy of the sensing methods. Integration of sample preparation techniques into these devices can effectively minimize the impact of complex food matrix on pathogen diagnosis and improve the limit of detections. Integration of pathogen capturing bio-receptors on microfluidic devices is a crucial step, which can facilitate recognition abilities in harsh chemical and physical conditions, offering a great commercial benefit to the food-manufacturing sector. This article reviews recent advances in current state-of-the-art of sample preparation and concentration from food matrices with focus on bacterial capturing methods and sensing technologies, along with their advantages and limitations when integrated into microfluidic devices for online rapid detection of pathogens in foods and food production line. Copyright © 2018. Published by Elsevier Inc.

Use of Metagenomic Shotgun Sequencing Technology To Detect Foodborne Pathogens within the Microbiome of the Beef Production Chain.

PubMed

Yang, Xiang; Noyes, Noelle R; Doster, Enrique; Martin, Jennifer N; Linke, Lyndsey M; Magnuson, Roberta J; Yang, Hua; Geornaras, Ifigenia; Woerner, Dale R; Jones, Kenneth L; Ruiz, Jaime; Boucher, Christina; Morley, Paul S; Belk, Keith E

2016-04-01

Foodborne illnesses associated with pathogenic bacteria are a global public health and economic challenge. The diversity of microorganisms (pathogenic and nonpathogenic) that exists within the food and meat industries complicates efforts to understand pathogen ecology. Further, little is known about the interaction of pathogens within the microbiome throughout the meat production chain. Here, a metagenomic approach and shotgun sequencing technology were used as tools to detect pathogenic bacteria in environmental samples collected from the same groups of cattle at different longitudinal processing steps of the beef production chain: cattle entry to feedlot, exit from feedlot, cattle transport trucks, abattoir holding pens, and the end of the fabrication system. The log read counts classified as pathogens per million reads for Salmonella enterica,Listeria monocytogenes,Escherichia coli,Staphylococcus aureus, Clostridium spp. (C. botulinum and C. perfringens), and Campylobacter spp. (C. jejuni,C. coli, and C. fetus) decreased over subsequential processing steps. Furthermore, the normalized read counts for S. enterica,E. coli, and C. botulinumwere greater in the final product than at the feedlots, indicating that the proportion of these bacteria increased (the effect on absolute numbers was unknown) within the remaining microbiome. From an ecological perspective, data indicated that shotgun metagenomics can be used to evaluate not only the microbiome but also shifts in pathogen populations during beef production. Nonetheless, there were several challenges in this analysis approach, one of the main ones being the identification of the specific pathogen from which the sequence reads originated, which makes this approach impractical for use in pathogen identification for regulatory and confirmation purposes. Copyright © 2016 Yang et al.

75 FR 80833 - Shipboard Air Emission Reduction Technology Report

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-23

... Reduction Technology Report AGENCY: Coast Guard, DHS. ACTION: Notice and request for comments. SUMMARY: In... Protection Agency, on Ship Emission Reduction Technology for cargo and passenger vessels that operate in... will survey new technology and new applications of existing technology for reducing air emissions from...

Pathogen inactivation treatment of plasma and platelet concentrates and their predicted functionality in massive transfusion protocols.

PubMed

Arbaeen, Ahmad F; Schubert, Peter; Serrano, Katherine; Carter, Cedric J; Culibrk, Brankica; Devine, Dana V

2017-05-01

Trauma transfusion packages for hemorrhage control consist of red blood cells, plasma, and platelets at a set ratio. Although pathogen reduction improves the transfusion safety of platelet and plasma units, there is an associated reduction in quality. This study aimed to investigate the impact of riboflavin/ultraviolet light-treated plasma or platelets in transfusion trauma packages composed of red blood cell, plasma, and platelet units in a ratio of 1:1:1 in vitro by modeling transfusion scenarios for trauma patients and assessing function by rotational thromboelastometry. Pathogen-reduced or untreated plasma and buffy coat platelet concentrate units produced in plasma were used in different combinations with red blood cells in trauma transfusion packages. After reconstitution of these packages with hemodiluted blood, the hemostatic functionality was analyzed by rotational thromboelastometry. Hemostatic profiles of pathogen-inactivated buffy coat platelet concentrate and plasma indicated decreased activity compared with their respective controls. Reconstitution of hemodiluted blood (hematocrit = 20%) with packages that contained treated or nontreated components resulted in increased alpha and maximum clot firmness and enhanced clot-formation time. Simulating transfusion scenarios based on 30% blood replacement with a transfusion trauma package resulted in a nonsignificant difference in rotational thromboelastometry parameters between packages containing treated and nontreated blood components (p ≥ 0.05). Effects of pathogen inactivation treatment were evident when the trauma package percentage was 50% or greater and contained both pathogen inactivation-treated plasma and buffy coat platelet concentrate. Rotational thromboelastometry investigations suggest that there is relatively little impact of pathogen inactivation treatment on whole blood clot formation unless large amounts of treated components are used. © 2017 AABB.

Effects of damping-off caused by Rhizoctonia solani anastomosis group 2-1 on roots of wheat and oil seed rape quantified using X-ray Computed Tomography and real-time PCR

PubMed Central

Sturrock, Craig J.; Woodhall, James; Brown, Matthew; Walker, Catherine; Mooney, Sacha J.; Ray, Rumiana V.

2015-01-01

Rhizoctonia solani is a plant pathogenic fungus that causes significant establishment and yield losses to several important food crops globally. This is the first application of high resolution X-ray micro Computed Tomography (X-ray μCT) and real-time PCR to study host–pathogen interactions in situ and elucidate the mechanism of Rhizoctonia damping-off disease over a 6-day period caused by R. solani, anastomosis group (AG) 2-1 in wheat (Triticum aestivum cv. Gallant) and oil seed rape (OSR, Brassica napus cv. Marinka). Temporal, non-destructive analysis of root system architectures was performed using RooTrak and validated by the destructive method of root washing. Disease was assessed visually and related to pathogen DNA quantification in soil using real-time PCR. R. solani AG2-1 at similar initial DNA concentrations in soil was capable of causing significant damage to the developing root systems of both wheat and OSR. Disease caused reductions in primary root number, root volume, root surface area, and convex hull which were affected less in the monocotyledonous host. Wheat was more tolerant to the pathogen, exhibited fewer symptoms and developed more complex root systems. In contrast, R. solani caused earlier damage and maceration of the taproot of the dicot, OSR. Disease severity was related to pathogen DNA accumulation in soil only for OSR, however, reductions in root traits were significantly associated with both disease and pathogen DNA. The method offers the first steps in advancing current understanding of soil-borne pathogen behavior in situ at the pore scale, which may lead to the development of mitigation measures to combat disease influence in the field. PMID:26157449

Effects of damping-off caused by Rhizoctonia solani anastomosis group 2-1 on roots of wheat and oil seed rape quantified using X-ray Computed Tomography and real-time PCR.

PubMed

Sturrock, Craig J; Woodhall, James; Brown, Matthew; Walker, Catherine; Mooney, Sacha J; Ray, Rumiana V

2015-01-01

Rhizoctonia solani is a plant pathogenic fungus that causes significant establishment and yield losses to several important food crops globally. This is the first application of high resolution X-ray micro Computed Tomography (X-ray μCT) and real-time PCR to study host-pathogen interactions in situ and elucidate the mechanism of Rhizoctonia damping-off disease over a 6-day period caused by R. solani, anastomosis group (AG) 2-1 in wheat (Triticum aestivum cv. Gallant) and oil seed rape (OSR, Brassica napus cv. Marinka). Temporal, non-destructive analysis of root system architectures was performed using RooTrak and validated by the destructive method of root washing. Disease was assessed visually and related to pathogen DNA quantification in soil using real-time PCR. R. solani AG2-1 at similar initial DNA concentrations in soil was capable of causing significant damage to the developing root systems of both wheat and OSR. Disease caused reductions in primary root number, root volume, root surface area, and convex hull which were affected less in the monocotyledonous host. Wheat was more tolerant to the pathogen, exhibited fewer symptoms and developed more complex root systems. In contrast, R. solani caused earlier damage and maceration of the taproot of the dicot, OSR. Disease severity was related to pathogen DNA accumulation in soil only for OSR, however, reductions in root traits were significantly associated with both disease and pathogen DNA. The method offers the first steps in advancing current understanding of soil-borne pathogen behavior in situ at the pore scale, which may lead to the development of mitigation measures to combat disease influence in the field.

Review of literature on climate change and forest diseases of western North America

Treesearch

John T. Kliejunas; Brian W. Geils; Jessie Micales Glaeser; Ellen Michaels Goheen; Paul Hennon; Mee-Sook Kim; Harry Kope; Jeff Stone; Rona Sturrock; Susan J. Frankel

2009-01-01

A summary of the literature on relationships between climate and various types of tree diseases, and the potential effects of climate change on pathogens in western North American forests is provided. Climate change generally will lead to reductions in tree health and will improve conditions for some highly damaging pathogens. Sections on abiotic diseases, declines,...

Biochar, Bentonite and Zeolite Supplemented Feeding of Layer Chickens Alters Intestinal Microbiota and Reduces Campylobacter Load

PubMed Central

Prasai, Tanka P.; Walsh, Kerry B.; Bhattarai, Surya P.; Midmore, David J.; Van, Thi T. H.; Moore, Robert J.; Stanley, Dragana

2016-01-01

A range of feed supplements, including antibiotics, have been commonly used in poultry production to improve health and productivity. Alternative methods are needed to suppress pathogen loads and maintain productivity. As an alternative to antibiotics use, we investigated the ability of biochar, bentonite and zeolite as separate 4% feed additives, to selectively remove pathogens without reducing microbial richness and diversity in the gut. Neither biochar, bentonite nor zeolite made any significant alterations to the overall richness and diversity of intestinal bacterial community. However, reduction of some bacterial species, including some potential pathogens was detected. The microbiota of bentonite fed animals were lacking all members of the order Campylobacterales. Specifically, the following operational taxonomic units (OTUs) were absent: an OTU 100% identical to Campylobacter jejuni; an OTU 99% identical to Helicobacter pullorum; multiple Gallibacterium anatis (>97%) related OTUs; Bacteroides dorei (99%) and Clostridium aldenense (95%) related OTUs. Biochar and zeolite treatments had similar but milder effects compared to bentonite. Zeolite amended feed was also associated with significant reduction in the phylum Proteobacteria. All three additives showed potential for the control of major poultry zoonotic pathogens. PMID:27116607

Cleanliness in context: reconciling hygiene with a modern microbial perspective.

PubMed

Vandegrift, Roo; Bateman, Ashley C; Siemens, Kyla N; Nguyen, May; Wilson, Hannah E; Green, Jessica L; Van Den Wymelenberg, Kevin G; Hickey, Roxana J

2017-07-14

The concept of hygiene is rooted in the relationship between cleanliness and the maintenance of good health. Since the widespread acceptance of the germ theory of disease, hygiene has become increasingly conflated with sterilization. In reviewing studies across the hygiene literature (most often hand hygiene), we found that nearly all studies of hand hygiene utilize bulk reduction in bacterial load as a proxy for reduced transmission of pathogenic organisms. This treatment of hygiene may be insufficient in light of recent microbial ecology research, which has demonstrated that humans have intimate and evolutionarily significant relationships with a diverse assemblage of microorganisms (our microbiota). The human skin is home to a diverse and specific community of microorganisms, which include members that exist across the ecological spectrum from pathogen through commensal to mutualist. Most evidence suggests that the skin microbiota is likely of direct benefit to the host and only rarely exhibits pathogenicity. This complex ecological context suggests that the conception of hygiene as a unilateral reduction or removal of microbes has outlived its usefulness. As such, we suggest the explicit definition of hygiene as "those actions and practices that reduce the spread or transmission of pathogenic microorganisms, and thus reduce the incidence of disease."

MoSwi6, an APSES family transcription factor, interacts with MoMps1 and is required for hyphal and conidial morphogenesis, appressorial function, and pathogenicity of Magnaporthe oryzae

PubMed Central

Qi, Zhongqiang; Wang, Qi; Dou, Xianying; Wang, Wei; Zhao, Qian; Lv, Ruili; Zhang, Haifeng; Zheng, Xiaobo; Wang, Ping; Zhang, Zhengguang

2011-01-01

Magnaporthe oryzae MAPK MoMps1 plays a critical role in regulating various developmental processes including cell wall integrity, stress responses, and pathogenicity. To identify potential effectors of MoMps1, we characterized the function of MoSwi6, a homolog of Saccharomyces cerevisiae Swi6 downstream of MAPK Slt2 signaling. MoSwi6 interacted with MoMps1 both in vivo and in vitro, suggesting a possible functional link analogous to Swi6-Slt2 in S. cerevisiae. Targeted gene disruption of MoSWI6 resulted in multiple developmental defects, including reduced hyphal growth, abnormal formation of conidia and appressoria, and impaired appressorium function. The reduction in appressorial turgor pressure also contributed to an attenuation of pathogenicity. The ΔMoswi6 mutant also displayed a defect in cell wall integrity, was hypersensitive to the oxidative stress, and showed significant reduction in transcription and activities of extracellular enzymes including peroxidases and laccases. Collectively, these roles are similar to those of MoMps1, confirming that MoSwi6 functions in the MoMps1 pathway to govern growth, development, and full pathogenicity. PMID:22321443

Natural disturbance reduces disease risk in endangered rainforest frog populations

PubMed Central

Roznik, Elizabeth A.; Sapsford, Sarah J.; Pike, David A.; Schwarzkopf, Lin; Alford, Ross A.

2015-01-01

Natural disturbances can drive disease dynamics in animal populations by altering the microclimates experienced by hosts and their pathogens. Many pathogens are highly sensitive to temperature and moisture, and therefore small changes in habitat structure can alter the microclimate in ways that increase or decrease infection prevalence and intensity in host populations. Here we show that a reduction of rainforest canopy cover caused by a severe tropical cyclone decreased the risk of endangered rainforest frogs (Litoria rheocola) becoming infected by a fungal pathogen (Batrachochytrium dendrobatidis). Reductions in canopy cover increased the temperatures and rates of evaporative water loss in frog microhabitats, which reduced B. dendrobatidis infection risk in frogs by an average of 11–28% in cyclone-damaged areas, relative to unaffected areas. Natural disturbances to the rainforest canopy can therefore provide an immediate benefit to frogs by altering the microclimate in ways that reduce infection risk. This could increase host survival and reduce the probability of epidemic disease outbreaks. For amphibian populations under immediate threat from this pathogen, targeted manipulation of canopy cover could increase the availability of warmer, drier microclimates and therefore tip the balance from host extinction to coexistence. PMID:26294048

Natural disturbance reduces disease risk in endangered rainforest frog populations.

PubMed

Roznik, Elizabeth A; Sapsford, Sarah J; Pike, David A; Schwarzkopf, Lin; Alford, Ross A

2015-08-21

Natural disturbances can drive disease dynamics in animal populations by altering the microclimates experienced by hosts and their pathogens. Many pathogens are highly sensitive to temperature and moisture, and therefore small changes in habitat structure can alter the microclimate in ways that increase or decrease infection prevalence and intensity in host populations. Here we show that a reduction of rainforest canopy cover caused by a severe tropical cyclone decreased the risk of endangered rainforest frogs (Litoria rheocola) becoming infected by a fungal pathogen (Batrachochytrium dendrobatidis). Reductions in canopy cover increased the temperatures and rates of evaporative water loss in frog microhabitats, which reduced B. dendrobatidis infection risk in frogs by an average of 11-28% in cyclone-damaged areas, relative to unaffected areas. Natural disturbances to the rainforest canopy can therefore provide an immediate benefit to frogs by altering the microclimate in ways that reduce infection risk. This could increase host survival and reduce the probability of epidemic disease outbreaks. For amphibian populations under immediate threat from this pathogen, targeted manipulation of canopy cover could increase the availability of warmer, drier microclimates and therefore tip the balance from host extinction to coexistence.

Efficacy of UV-C irradiation for inactivation of food-borne pathogens on sliced cheese packaged with different types and thicknesses of plastic films.

PubMed

Ha, Jae-Won; Back, Kyeong-Hwan; Kim, Yoon-Hee; Kang, Dong-Hyun

2016-08-01

In this study, the efficacy of using UV-C light to inactivate sliced cheese inoculated with Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes and, packaged with 0.07 mm films of polyethylene terephthalate (PET), polyvinylchloride (PVC), polypropylene (PP), and polyethylene (PE) was investigated. The results show that compared with PET and PVC, PP and PE films showed significantly reduced levels of the three pathogens compared to inoculated but non-treated controls. Therefore, PP and PE films of different thicknesses (0.07 mm, 0.10 mm, and 0.13 mm) were then evaluated for pathogen reduction of inoculated sliced cheese samples. Compared with 0.10 and 0.13 mm, 0.07 mm thick PP and PE films did not show statistically significant reductions compared to non-packaged treated samples. Moreover, there were no statistically significant differences between the efficacy of PP and PE films. These results suggest that adjusted PP or PE film packaging in conjunction with UV-C radiation can be applied to control foodborne pathogens in the dairy industry. Copyright © 2016. Published by Elsevier Ltd.

Fitting new technologies into the safety paradigm: use of microarrays in transfusion.

PubMed

Fournier-Wirth, C; Coste, J

2007-01-01

Until the late 1990s, mandatory blood screening for transmissible infectious agents depended entirely on antigen/antibody-based detection assays. The recent emergence of Nucleic acid Amplification Technologies (NAT) has revolutionised viral diagnosis, not only by increasing the level of sensitivity but also by facilitating the detection of several viruses in parallel by multiplexing specific primers. In more complex biological situations, when a broad spectrum of pathogens must be screened, the limitations of these first generation technologies became apparent. High throughput systems, such as DNA Arrays, permit a conceptually new approach. These miniaturised micro systems allow the detection of hundreds of different targets simultaneously, inducing a dramatic decrease in reagent consumption, a reduction in the number of confirmation tests and a simplification of data interpretation. However, the systems currently available require additional instrumentation and reagents for sample preparation and target amplification prior to detection on the DNA array. A major challenge in the area of DNA detection is the development of methods that do not rely on target amplification systems. Likewise, the advances of protein microarrays have lagged because of poor stability of proteins, complex coupling chemistry and weak detection signals. Emerging technologies like Biosensors and nano-particle based DNA or Protein Bio-Barcode Amplification Assays are promising diagnostic tools for a wide range of clinical applications, including blood donation screening.

Reinforcing effects of non-pathogenic bacteria and predation risk: from physiology to life history.

PubMed

Janssens, Lizanne; Stoks, Robby

2014-10-01

The important ecological role of predation risk in shaping populations, communities and ecosystems is becoming increasingly clear. In this context, synergistic effects between predation risk and other natural stressors on prey organisms are gaining attention. Although non-pathogenic bacteria can be widespread in aquatic ecosystems, their role in mediating effects of predation risk has been ignored. We here address the hypothesis that non-pathogenic bacteria may reinforce the negative effects of predation risk in larvae of the damselfly Coenagrion puella. We found synergistic effects for all three life history variables studied: mortality increased, growth reductions were magnified and bacterial load was higher when both non-lethal stressors were combined. The combined exposure to the bacterium and predation risk considerably impaired the two key antipredator mechanisms of the damselfly larvae: they no longer reduced their food intake under predation risk and showed a synergistic reduction in escape swimming speed. The reinforcing negative effects on the fitness-related traits could be explained by the observed synergistic effects on food intake, swimming muscle mass, immune function and oxidative damage. These are likely widespread consequences of energetic constraints and increased metabolic rates associated with the fight-or-flight response. We therefore hypothesize that the here documented synergistic interactions with non-pathogenic bacteria may be widespread. Our results highlight the ignored ecological role of non-pathogenic bacteria in reinforcing the negative effects of predation risk on prey organisms.

Zeolite food supplementation reduces abundance of enterobacteria.

PubMed

Prasai, Tanka P; Walsh, Kerry B; Bhattarai, Surya P; Midmore, David J; Van, Thi T H; Moore, Robert J; Stanley, Dragana

2017-01-01

According to the World Health Organisation, antibiotics are rapidly losing potency in every country of the world. Poultry are currently perceived as a major source of pathogens and antimicrobial resistance. There is an urgent need for new and natural ways to control pathogens in poultry and humans alike. Porous, cation rich, aluminosilicate minerals, zeolites can be used as a feed additive in poultry rations, demonstrating multiple productivity benefits. Next generation sequencing of the 16S rRNA marker gene was used to phylogenetically characterize the fecal microbiota and thus investigate the ability and dose dependency of zeolite in terms of anti-pathogenic effects. A natural zeolite was used as a feed additive in laying hens at 1, 2, and 4% w/w for a 23 week period. At the end of this period cloacal swabs were collected to sample faecal microbial communities. A significant reduction in carriage of bacteria within the phylum Proteobacteria, especially in members of the pathogen-rich family Enterobacteriaceae, was noted across all three concentrations of zeolite. Zeolite supplementation of feed resulted in a reduction in the carriage of a number of poultry pathogens without disturbing beneficial bacteria. This effect was, in some phylotypes, correlated with the zeolite concentration. This result is relevant to zeolite feeding in other animal production systems, and for human pathogenesis. Copyright © 2016 Elsevier GmbH. All rights reserved.

40 CFR 503.27 - Recordkeeping.

Code of Federal Regulations, 2010 CFR

2010-07-01

... penalty of law, that the information that will be used to determine compliance with the pathogen... requirements is met) and the vector attraction reduction requirement in (insert one of the vector attraction... met. (iv) A description of how one of the vector attraction reduction requirements in § 503.33 (b)(1...

40 CFR 503.27 - Recordkeeping.

Code of Federal Regulations, 2014 CFR

2014-07-01

... penalty of law, that the information that will be used to determine compliance with the pathogen... requirements is met) and the vector attraction reduction requirement in (insert one of the vector attraction... met. (iv) A description of how one of the vector attraction reduction requirements in § 503.33 (b)(1...

40 CFR 503.27 - Recordkeeping.

Code of Federal Regulations, 2012 CFR

2012-07-01

... penalty of law, that the information that will be used to determine compliance with the pathogen... requirements is met) and the vector attraction reduction requirement in (insert one of the vector attraction... met. (iv) A description of how one of the vector attraction reduction requirements in § 503.33 (b)(1...

40 CFR 503.27 - Recordkeeping.

Code of Federal Regulations, 2013 CFR

2013-07-01

... penalty of law, that the information that will be used to determine compliance with the pathogen... requirements is met) and the vector attraction reduction requirement in (insert one of the vector attraction... met. (iv) A description of how one of the vector attraction reduction requirements in § 503.33 (b)(1...

78 FR 72626 - Notice of Request for Renewal of a Currently Approved Information Collection (Pathogen Reduction...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-03

... reduction and Hazard Analysis and Critical Control Point (HACCP) Systems requirements because OMB approval... February 28, 2014. FSIS has established requirements applicable to meat and poultry establishments designed.... coli by slaughter establishments to verify the adequacy of the establishment's process controls for the...

RAPID TETRAZOLIUM DYE REDUCTION ASSAY TO ASSESS THE BACTERICIDAL ACTIVITY OF OYSTER (CRASSOSTREA VIRGINICA) HEMOCYTES AGAINST VIBRIO PARAHAEMOLYTICUS

EPA Science Inventory

An assay was developed to assess the ability of oyster, Crassostrea virginica, hemocytes to kill the human pathogenic bacterium, Vibrio parahaemolyticus (ATCC 17802). Bacterial killing was estimated colorimetrically by the enzymatic reduction of a tetrazolium dye, 3-(4,5-dimethyl...

Can water quality of tubewells be assessed without chemical testing?

NASA Astrophysics Data System (ADS)

Hoque, Mohammad A.; Butler, Adrian P.

2016-04-01

Arsenic is one of the major pollutants found in aquifers on a global scale. The screening of tubewells for arsenic has helped many people to avoid drinking from highly polluted wells in the Bengal Delta (West Bengal and Bangladesh). However, there are still many millions of tubewells in Bangladesh yet to be tested, and a substantial proportion of these are likely to contain excessive arsenic. Due to the level of poverty and lack of infrastructure, it is unlikely that the rest of the tubewells will be tested quickly. However, water quality assessment without needing a chemical testing may be helpful in this case. Studies have found that qualitative factors, such as staining in the tubewell basement and/or on utensils, can indicate subsurface geology and water quality. The science behind this staining is well established, red staining is associated with iron reduction leading to release of arsenic whilst black staining is associated with manganese reduction (any release of arsenic due to manganese reduction is sorbed back on the, yet to be reduced, iron), whereas mixed staining may indicate overlapping manganese and iron reduction at the tubewell screen. Reduction is not uniform everywhere and hence chemical water quality including dissolved arsenic varies from place to place. This is why coupling existing tubewell arsenic information with user derived staining data could be useful in predicting the arsenic status at a particular site. Using well location, depth, along with colour of staining, an assessment of both good (nutrients) and bad (toxins and pathogens) substances in the tubewell could be provided. Social-network technology, combined with increasing use of smartphones, provides a powerful opportunity for both sharing and providing feedback to the user. Here we outline how a simple digital application can couple the reception both qualitative and quantitative tubewell data into a centralised interactive database and provide manipulated feedback to an individual user. This technology has the potential to reach more than 50 million people in the Bengal delta and can play an effective role in arsenic mitigation and water quality assessment in similar geological terrains.

In-Vessel Composting of Simulated Long-Term Missions Space-Related Solid Wastes

NASA Technical Reports Server (NTRS)

Rodriguez-Carias, Abner A.; Sager, John; Krumins, Valdis; Strayer, Richard; Hummerick, Mary; Roberts, Michael S.

2002-01-01

Reduction and stabilization of solid wastes generated during space missions is a major concern for the Advanced Life Support - Resource Recovery program at the NASA, Kennedy Space Center. Solid wastes provide substrates for pathogen proliferation, produce strong odor, and increase storage requirements during space missions. A five periods experiment was conducted to evaluate the Space Operation Bioconverter (SOB), an in vessel composting system, as a biological processing technology to reduce and stabilize simulated long-term missions space related solid-wastes (SRSW). For all periods, SRSW were sorted into components with fast (FBD) and slow (SBD) biodegradability. Uneaten food and plastic were used as a major FBD and SBD components, respectively. Compost temperature (C), CO2 production (%), mass reduction (%), and final pH were utilized as criteria to determine compost quality. In period 1, SOB was loaded with a 55% FBD: 45% SBD mixture and was allowed to compost for 7 days. An eleven day second composting period was conducted loading the SOB with 45% pre-composted SRSW and 55% FBD. Period 3 and 4 evaluated the use of styrofoam as a bulking agent and the substitution of regular by degradable plastic on the composting characteristics of SRSW, respectively. The use of ceramic as a bulking agent and the relationship between initial FBD mass and heat production was investigated in period 5. Composting SRSW resulted in an acidic fermentation with a minor increase in compost temperature, low CO2 production, and slightly mass reduction. Addition of styrofoam as a bulking agent and substitution of regular by biodegradable plastic improved the composting characteristics of SRSW, as evidenced by higher pH, CO2 production, compost temperature and mass reduction. Ceramic as a bulking agent and increase the initial FBD mass (4.4 kg) did not improve the composting process. In summary, the SOB is a potential biological technology for reduction and stabilization of mission space-related solid wastes. However, the success of the composting process may depend of the physical characteristics (particle size, porosity, structure, texture) of the SBD components which would require pre-processing of solid wastes before placing them in the SOB.

Food Safety and Intervention Technologies Research: Cold Plasma as a Nonthermal food processing technology

USDA-ARS?s Scientific Manuscript database

Contamination of meats, seafood, poultry, eggs, and fresh and fresh-cut fruits and vegetables is an ongoing concern. The Food Safety and Intervention Technologies Research Unit develops and validates innovative approaches and new technologies that control pathogenic bacteria and viruses while preser...

Food Safety and Intervention Technologies research: cold plasma as a nonthermal food processing technology

USDA-ARS?s Scientific Manuscript database

Contamination of meats, seafood, poultry, eggs, and fresh and fresh-cut fruits and vegetables is an ongoing concern. The Food Safety and Intervention Technologies Research Unit develops and validates innovative approaches and new technologies that control pathogenic bacteria and viruses while preser...

RECOVERY AND ASSAY OF VIRUSES FROM BIOSOLIDS

EPA Science Inventory

In a review of EPA's rule on sewage sludges, the National Research Council recommended that EPA develop improved methods for pathogens using modern technologies. They specifically mentioned viral pathogens that cannot be cultured and those that are difficult to culture. As a re...

The Promise of Whole Genome Pathogen Sequencing for the Molecular Epidemiology of Emerging Aquaculture Pathogens

PubMed Central

Bayliss, Sion C.; Verner-Jeffreys, David W.; Bartie, Kerry L.; Aanensen, David M.; Sheppard, Samuel K.; Adams, Alexandra; Feil, Edward J.

2017-01-01

Aquaculture is the fastest growing food-producing sector, and the sustainability of this industry is critical both for global food security and economic welfare. The management of infectious disease represents a key challenge. Here, we discuss the opportunities afforded by whole genome sequencing of bacterial and viral pathogens of aquaculture to mitigate disease emergence and spread. We outline, by way of comparison, how sequencing technology is transforming the molecular epidemiology of pathogens of public health importance, emphasizing the importance of community-oriented databases and analysis tools. PMID:28217117

The application of bioflocs technology to protect brine shrimp (Artemia franciscana) from pathogenic Vibrio harveyi.

PubMed

Crab, R; Lambert, A; Defoirdt, T; Bossier, P; Verstraete, W

2010-11-01

To study the potential biocontrol activity of bioflocs technology. Glycerol-grown bioflocs were investigated for their antimicrobial and antipathogenic properties against the opportunistic pathogen Vibrio harveyi. The bioflocs did not produce growth-inhibitory substances. However, bioflocs and biofloc supernatants decreased quorum sensing-regulated bioluminescence of V. harveyi. This suggested that the bioflocs had biocontrol activity against this pathogen because quorum sensing regulates virulence of vibrios towards different hosts. Interestingly, the addition of live bioflocs significantly increased the survival of gnotobiotic brine shrimp (Artemia franciscana) larvae challenged to V. harveyi. Bioflocs grown on glycerol as carbon source inhibit quorum sensing-regulated bioluminescence in V. harveyi and protect brine shrimp larvae from vibriosis. The results presented in this study indicate that in addition to water quality control and in situ feed production, bioflocs technology could help in controlling bacterial infections within the aquaculture pond. © 2010 The Authors. Journal of Applied Microbiology © 2010 The Society for Applied Microbiology.

Overview and challenges of molecular technologies in the veterinary microbiology laboratory.

PubMed

Cunha, Mónica V; Inácio, João

2015-01-01

Terrestrial, aquatic, and aerial animals, either domestic or wild, humans, and plants all face similar health threats caused by infectious agents. Multifaceted anthropic pressure caused by an increasingly growing and resource-demanding human population has affected biodiversity at all scales, from the DNA molecule to the pathogen, to the ecosystem level, leading to species declines and extinctions and, also, to host-pathogen coevolution processes. Technological developments over the last century have also led to quantic jumps in laboratorial testing that have highly impacted animal health and welfare, ameliorated animal management and animal trade, safeguarded public health, and ultimately helped to "secure" biodiversity. In particular, the field of molecular diagnostics experienced tremendous technical progresses over the last two decades that significantly have contributed to our ability to study microbial pathogens in the clinical and research laboratories. This chapter highlights the strengths, weaknesses, opportunities, and threats (or challenges) of molecular technologies in the framework of a veterinary microbiology laboratory, in view of the latest advances.

Mitochondrial Effects of PGC-1alpha Silencing in MPP+ Treated Human SH-SY5Y Neuroblastoma Cells

PubMed Central

Ye, Qinyong; Chen, Chun; Si, Erwang; Cai, Yousheng; Wang, Juhua; Huang, Wanling; Li, Dongzhu; Wang, Yingqing; Chen, Xiaochun

2017-01-01

The dopaminergic neuron degeneration and loss that occurs in Parkinson’s disease (PD) has been tightly linked to mitochondrial dysfunction. Although the aged-related cause of the mitochondrial defect observed in PD patients remains unclear, nuclear genes are of potential importance to mitochondrial function. Human peroxisome proliferator-activated receptor γ coactivator-1alpha (PGC-1α) is a multi-functional transcription factor that tightly regulates mitochondrial biogenesis and oxidative capacity. The goal of the present study was to explore the potential pathogenic effects of interference by the PGC-1α gene on N-methyl-4-phenylpyridinium ion (MPP+)-induced SH-SY5Y cells. We utilized RNA interference (RNAi) technology to probe the pathogenic consequences of inhibiting PGC-1α in the SH-SY5Y cell line. Remarkably, a reduction in PGC-1α resulted in the reduction of mitochondrial membrane potential, intracellular ATP content and intracellular H2O2 generation, leading to the translocation of cytochrome c (cyt c) to the cytoplasm in the MPP+-induced PD cell model. The expression of related proteins in the signaling pathway (e.g., estrogen-related receptor α (ERRα), nuclear respiratory factor 1 (NRF-1), NRF-2 and Peroxisome proliferator-activated receptor γ (PPARγ)) also decreased. Our finding indicates that small interfering RNA (siRNA) interference targeting the PGC-1α gene could inhibit the function of mitochondria in several capacities and that the PGC-1α gene may modulate mitochondrial function by regulating the expression of ERRα, NRF-1, NRF-2 and PPARγ. Thus, PGC-1α can be considered a potential therapeutic target for PD. PMID:28611589

Light based technologies for microbial inactivation of liquids, bead surfaces and powdered infant formula.

PubMed

Arroyo, Cristina; Dorozko, Anna; Gaston, Edurne; O'Sullivan, Michael; Whyte, Paul; Lyng, James G

2017-10-01

This study evaluates the potential of continuous wave Ultraviolet C light (UV-C) and broad-spectrum intense pulsed light (in this study referred to as High Intensity Light Pulses, HILP) for the inactivation of pathogens of public concern in powdered infant formula (PIF) producers. To achieve this goal a sequential set of experiments were performed, firstly in clear liquid media, secondly on the surface of spherical beads under agitation and, finally in PIF. L. innocua was the most sensitive microorganism to both technologies under all conditions studied with reductions exceeding 4 log 10 cycles in PIF. In the clear liquid medium, the maximum tolerance to light was observed for C. sakazakii against UV-C light and for B. subtilis spores against HILP, with a fluence of approximately 17 mJ/cm 2 required for a 1 log 10 cycle inactivation (D value) of each species. In PIF it was possible to inactivate >99% of the vegetative cell populations by HILP with a fluence of 199 mJ/cm 2 and of B. subtilis spores by doubling the fluence. By contrast, for UV-C treatments a fluence of 2853 mJ/cm 2 was needed for 99.9% reduction of C. sakazakii, which was the most light-resistant microorganism to UV-C. Results here obtained clearly show the potential for light-based interventions to improve PIF microbiological safety. Copyright © 2017 Elsevier Ltd. All rights reserved.

Acidic Electrolyzed Water as a Novel Transmitting Medium for High Hydrostatic Pressure Reduction of Bacterial Loads on Shelled Fresh Shrimp

PubMed Central

Du, Suping; Zhang, Zhaohuan; Xiao, Lili; Lou, Yang; Pan, Yingjie; Zhao, Yong

2016-01-01

Acidic electrolyzed water (AEW), a novel non-thermal sterilization technology, is widely used in the food industry. In this study, we firstly investigated the effect of AEW as a new pressure transmitting medium for high hydrostatic pressure (AEW-HHP) processing on microorganisms inactivation on shelled fresh shrimp. The optimal conditions of AEW-HHP for Vibrio parahaemolyticus inactivation on sterile shelled fresh shrimp were obtained using response surface methodology: NaCl concentration to electrolysis 1.5 g/L, treatment pressure 400 MPa, treatment time 10 min. Under the optimal conditions mentioned above, AEW dramatically enhanced the efficiency of HHP for inactivating V. parahaemolyticus and Listeria monocytogenes on artificially contaminated shelled fresh shrimp, and the log reductions were up to 6.08 and 5.71 log10 CFU/g respectively, while the common HHP could only inactivate the two pathogens up to 4.74 and 4.31 log10 CFU/g respectively. Meanwhile, scanning electron microscopy (SEM) showed the same phenomenon. For the naturally contaminated shelled fresh shrimp, AEW-HHP could also significantly reduce the micro flora when examined using plate count and PCR-DGGE. There were also no significant changes, histologically, in the muscle tissues of shrimps undergoing the AEW-HHP treatment. In summary, using AEW as a new transmitting medium for HHP processing is an innovative non thermal technology for improving the food safety of shrimp and other aquatic products. PMID:27014228

Evaluation of detection methods for screening meat and poultry products for the presence of foodborne pathogens.

PubMed

Bohaychuk, Valerie M; Gensler, Gary E; King, Robin K; Wu, John T; McMullen, Lynn M

2005-12-01

Rapid and molecular technologies such as enzyme-linked immunosorbent assay (ELISA), PCR, and lateral flow immunoprecipitation can reduce the time and labor involved in screening food products for the presence of pathogens. These technologies were compared with conventional culture methodology for the detection of Salmonella, Campylobacter, Listeria, and Escherichia coli O157:H7 inoculated in raw and processed meat and poultry products. Recommended protocols were modified so that the same enrichment broths used in the culture methods were also used in the ELISA, PCR, and lateral flow immunoprecipitation assays. The percent agreement between the rapid technologies and culture methods ranged from 80 to 100% depending on the pathogen detected and the method used. ELISA, PCR, and lateral flow immunoprecipitation all performed well, with no statistical difference, compared with the culture method for the detection of E. coli O157:H7. ELISA performed better for the detection of Salmonella, with sensitivity and specificity rates of 100%. PCR performed better for the detection of Campylobacter jejuni, with 100% agreement to the culture method. PCR was highly sensitive for the detection of all the foodborne pathogens tested except Listeria monocytogenes. Although the lateral flow immunoprecipitation tests were statistically different from the culture methods for Salmonella and Listeria because of false-positive results, the tests did not produce any false negatives, indicating that this method would be suitable for screening meat and poultry products for these pathogens.

Survival of selected foodborne pathogens on dry cured pork loins.

PubMed

Morales-Partera, Ángela M; Cardoso-Toset, Fernando; Jurado-Martos, Francisco; Astorga, Rafael J; Huerta, Belén; Luque, Inmaculada; Tarradas, Carmen; Gómez-Laguna, Jaime

2017-10-03

The safety of ready-to-eat products such as cured pork loins must be guaranteed by the food industry. In the present study, the efficacy of the dry curing process of pork loins obtained from free-range pigs in the reduction of three of the most important foodborne pathogens is analysed. A total of 28 pork loin segments, with an average weight of 0.57±0.12kg, were divided into four groups with three being inoculated by immersion with 7logCFU/ml of either Salmonella Typhimurium, Campylobacter coli or Listeria innocua and the last one inoculated by immersion with sterile medium (control group). The loin segments were treated with a seasoning mixture of curing agents and spices, packed in a synthetic sausage casing and cured for 64days. Microbiological analysis, pH and water activity (a w ) were assessed at four stages. The values of pH and a w decreased with curing time as expected. S. Typhimurium and C. coli dropped significantly (3.28 and 2.14 log units, respectively), but limited reduction of L. innocua (0.84 log unit) was observed along the curing process. In our study, three factors were considered critical: the initial concentration of the bacteria, the progressive reduction of pH and the reduction of a w values. Our results encourage performing periodic analysis at different stages of the manufacturing of dry cured pork loins to ensure the absence of the three evaluated foodborne pathogens. Copyright © 2017 Elsevier B.V. All rights reserved.

Microbial risk assessment of drinking water based on hydrodynamic modelling of pathogen concentrations in source water.

PubMed

Sokolova, Ekaterina; Petterson, Susan R; Dienus, Olaf; Nyström, Fredrik; Lindgren, Per-Eric; Pettersson, Thomas J R

2015-09-01

Norovirus contamination of drinking water sources is an important cause of waterborne disease outbreaks. Knowledge on pathogen concentrations in source water is needed to assess the ability of a drinking water treatment plant (DWTP) to provide safe drinking water. However, pathogen enumeration in source water samples is often not sufficient to describe the source water quality. In this study, the norovirus concentrations were characterised at the contamination source, i.e. in sewage discharges. Then, the transport of norovirus within the water source (the river Göta älv in Sweden) under different loading conditions was simulated using a hydrodynamic model. Based on the estimated concentrations in source water, the required reduction of norovirus at the DWTP was calculated using quantitative microbial risk assessment (QMRA). The required reduction was compared with the estimated treatment performance at the DWTP. The average estimated concentration in source water varied between 4.8×10(2) and 7.5×10(3) genome equivalents L(-1); and the average required reduction by treatment was between 7.6 and 8.8 Log10. The treatment performance at the DWTP was estimated to be adequate to deal with all tested loading conditions, but was heavily dependent on chlorine disinfection, with the risk of poor reduction by conventional treatment and slow sand filtration. To our knowledge, this is the first article to employ discharge-based QMRA, combined with hydrodynamic modelling, in the context of drinking water. Copyright © 2015 Elsevier B.V. All rights reserved.

Protection from pulmonary tissue damage associated with infection of cynomolgus macaques by highly pathogenic avian influenza virus (H5N1) by low dose natural human IFN-α administered to the buccal mucosa.

PubMed

Strayer, David R; Carter, William A; Stouch, Bruce C; Stittelaar, Koert J; Thoolen, Robert J M M; Osterhaus, Albert D M E; Mitchell, William M

2014-10-01

Using an established nonhuman primate model for H5N1 highly pathogenic influenza virus infection in humans, we have been able to demonstrate the prophylactic mitigation of the pulmonary damage characteristic of human fatal cases from primary influenza virus pneumonia with a low dose oral formulation of a commercially available parenteral natural human interferon alpha (Alferon N Injection®). At the highest oral dose (62.5IU/kg body weight) used there was a marked reduction in the alveolar inflammatory response with minor evidence of alveolar and interstitial edema in contrast to the hemorrhage and inflammatory response observed in the alveoli of control animals. The mitigation of severe damage to the lower pulmonary airway was observed without a parallel reduction in viral titers. Clinical trial data will be necessary to establish its prophylactic human efficacy for highly pathogenic influenza viruses. Copyright © 2014. Published by Elsevier B.V.

Radiation technology for environmental conservation

NASA Astrophysics Data System (ADS)

Machi, S.

The use of radiation technology for environmental conservation is becoming increasingly important. Commercial plants for the radiation treatment of sewage sludge to reduce pathogenic micro-organisms have been operating in the Federal Republic of Germany for the past ten years and their technical and economical feasibility has been demonstrated. Irradiation of dried sludge has been developed at the Sandia National Laboratory (USA) using Cs-137, and the construction of a commercial plant is planned in Albuquerque. At the Japan Atomic Energy Research Institute (JAERI), efforts are under way to increase the rate of composting of sludge by radiation. Regarding waste water treatment, a significant synergistic effect of radiation and ozone was found in the reduction of TOC. The construction of a gamma irradiation plant is in the planning stage in Canada, for the disinfection of virus-contaminated waste effluents from the Canadian Animal Disease Research Institute. The treatment of exhaust gases by electron beam has been studied in Japan using a large pilot plant which demonstrated that 90% of SO 2 and 80% of NO x can be removed from the flue gas of iron ore sintering furnaces. The US Department of Energy is assisting in projects for the further development of this technology for combined removal of SO 2 and NO x in flue gas from coal burning power stations.

Selection of surrogate bacteria in place of E. coli O157:H7 and Salmonella Typhimurium for pulsed electric field treatment of orange juice.

PubMed

Gurtler, Joshua B; Rivera, Rebecca B; Zhang, Howard Q; Geveke, David J

2010-04-30

Pulsed electric field (PEF) technology has been used for the inactivation of microorganisms and to prevent flavor loss in liquid foods and beverages in place of thermal pasteurization. When used to pasteurize orange juice, PEF may prevent loss of volatile sensory attributes. Enterohemorrhagic E. coli O157:H7 (EHEC), two strains of Salmonella Typhimurium, and twenty strains of non-pathogenic bacteria were screened for inactivation in orange juice by PEF at 22 and 20kV/cm at 45 and 55 degrees C, respectively. Higher populations of both salmonellae were inactivated (2.81 and 3.54 log CFU/ml) at 55 degrees C, in comparison with the reduction of EHEC (2.22 log). When tested under the same conditions, inactivation of EHEC was slightly greater than that of a non-pathogenic E. coli (NPEC) ATCC 35218 (2.02 log). NPEC was further tested as a surrogate for EHEC by comparing inactivation kinetics at 45, 50 and 55 degrees C at field strengths of between 7.86 and 32.55kV/cm. Statistical comparison of revealed that EHEC and NPEC inactivation curves were homogeneous at outlet temperatures of 45 and 50 degrees C; however, EHEC was slightly more sensitive to PEF than the surrogate NPEC at 55 degrees C. The higher PEF resistance of non-pathogenic E. coli 35218 at 55 degrees C may provide a desirable margin of safety when used in pilot plant challenge studies in place of E. coli O157:H7. Published by Elsevier B.V.

FROM CONCEPT TO EQUIVALENCY: THE 503 REGULATIONS AND THE PATHOGEN EQUIVALENCY COMMITTEE

EPA Science Inventory

Since its creation in 1985, the Pathogen Equivalency Committee (PEC) has been reviewing innovative and alternative sludge disinfection technologies with regards to their abilities to protect human health and the environment. The PEC is charged to make recommendations on whether t...

Cold Plasma as a novel intervention against food-borne pathogens

USDA-ARS?s Scientific Manuscript database

Contamination of meats, seafood, fresh and fresh-cut fruits and vegetables and other foods by foodborne pathogens has prompted research into novel interventions. Cold plasma is a nonthermal food processing technology which uses energetic, reactive gases to inactivate contaminating microbes. This fle...

Tick-Pathogen Interactions and Vector Competence: Identification of Molecular Drivers for Tick-Borne Diseases

PubMed Central

de la Fuente, José; Antunes, Sandra; Bonnet, Sarah; Cabezas-Cruz, Alejandro; Domingos, Ana G.; Estrada-Peña, Agustín; Johnson, Nicholas; Kocan, Katherine M.; Mansfield, Karen L.; Nijhof, Ard M.; Papa, Anna; Rudenko, Nataliia; Villar, Margarita; Alberdi, Pilar; Torina, Alessandra; Ayllón, Nieves; Vancova, Marie; Golovchenko, Maryna; Grubhoffer, Libor; Caracappa, Santo; Fooks, Anthony R.; Gortazar, Christian; Rego, Ryan O. M.

2017-01-01

Ticks and the pathogens they transmit constitute a growing burden for human and animal health worldwide. Vector competence is a component of vectorial capacity and depends on genetic determinants affecting the ability of a vector to transmit a pathogen. These determinants affect traits such as tick-host-pathogen and susceptibility to pathogen infection. Therefore, the elucidation of the mechanisms involved in tick-pathogen interactions that affect vector competence is essential for the identification of molecular drivers for tick-borne diseases. In this review, we provide a comprehensive overview of tick-pathogen molecular interactions for bacteria, viruses, and protozoa affecting human and animal health. Additionally, the impact of tick microbiome on these interactions was considered. Results show that different pathogens evolved similar strategies such as manipulation of the immune response to infect vectors and facilitate multiplication and transmission. Furthermore, some of these strategies may be used by pathogens to infect both tick and mammalian hosts. Identification of interactions that promote tick survival, spread, and pathogen transmission provides the opportunity to disrupt these interactions and lead to a reduction in tick burden and the prevalence of tick-borne diseases. Targeting some of the similar mechanisms used by the pathogens for infection and transmission by ticks may assist in development of preventative strategies against multiple tick-borne diseases. PMID:28439499

Recent Advances in Biosensor Development for Foodborne Virus Detection

PubMed Central

Neethirajan, Suresh; Ahmed, Syed Rahin; Chand, Rohit; Buozis, John; Nagy, Éva

2017-01-01

Outbreaks of foodborne diseases related to fresh produce have been increasing in North America and Europe. Viral foodborne pathogens are poorly understood, suffering from insufficient awareness and surveillance due to the limits on knowledge, availability, and costs of related technologies and devices. Current foodborne viruses are emphasized and newly emerging foodborne viruses are beginning to attract interest. To face current challenges regarding foodborne pathogens, a point-of-care (POC) concept has been introduced to food testing technology and device. POC device development involves technologies such as microfluidics, nanomaterials, biosensors and other advanced techniques. These advanced technologies, together with the challenges in developing foodborne virus detection assays and devices, are described and analysed in this critical review. Advanced technologies provide a path forward for foodborne virus detection, but more research and development will be needed to provide the level of manufacturing capacity required. PMID:29071193

Fate of pathogens present in livestock wastes spread onto fescue plots.

PubMed

Hutchison, Mike L; Walters, Lisa D; Moore, Tony; Thomas, D John I; Avery, Sheryl M

2005-02-01

Fecal wastes from a variety of farmed livestock were inoculated with livestock isolates of Escherichia coli O157, Listeria monocytogenes, Salmonella, Campylobacter jejuni, and Cryptosporidium parvum oocysts at levels representative of the levels found in naturally contaminated wastes. The wastes were subsequently spread onto a grass pasture, and the decline of each of the zoonotic agents was monitored over time. There were no significant differences among the decimal reduction times for the bacterial pathogens. The mean bacterial decimal reduction time was 1.94 days. A range of times between 8 and 31 days for a 1-log reduction in C. parvum levels was obtained, demonstrating that the protozoans were significantly more hardy than the bacteria. Oocyst recovery was more efficient from wastes with lower dry matter contents. The levels of most of the zoonotic agents had declined to below detectable levels by 64 days. However, for some waste types, 128 days was required for the complete decline of L. monocytogenes levels. We were unable to find significant differences between the rates of pathogen decline in liquid (slurry) and solid (farmyard manure) wastes, although concerns have been raised that increased slurry generation as a consequence of more intensive farming practices could lead to increased survival of zoonotic agents in the environment.

Application of FTA technology for sampling, recovery and molecular characterization of viral pathogens and virus-derived transgenes from plant tissues.

PubMed

Ndunguru, Joseph; Taylor, Nigel J; Yadav, Jitender; Aly, Haytham; Legg, James P; Aveling, Terry; Thompson, Graham; Fauquet, Claude M

2005-05-18

Plant viral diseases present major constraints to crop production. Effective sampling of the viruses infecting plants is required to facilitate their molecular study and is essential for the development of crop protection and improvement programs. Retaining integrity of viral pathogens within sampled plant tissues is often a limiting factor in this process, most especially when sample sizes are large and when operating in developing counties and regions remote from laboratory facilities. FTA is a paper-based system designed to fix and store nucleic acids directly from fresh tissues pressed into the treated paper. We report here the use of FTA as an effective technology for sampling and retrieval of DNA and RNA viruses from plant tissues and their subsequent molecular analysis. DNA and RNA viruses were successfully recovered from leaf tissues of maize, cassava, tomato and tobacco pressed into FTA Classic Cards. Viral nucleic acids eluted from FTA cards were found to be suitable for diagnostic molecular analysis by PCR-based techniques and restriction analysis, and for cloning and nucleotide sequencing in a manner equivalent to that offered by tradition isolation methods. Efficacy of the technology was demonstrated both from sampled greenhouse-grown plants and from leaf presses taken from crop plants growing in farmer's fields in East Africa. In addition, FTA technology was shown to be suitable for recovery of viral-derived transgene sequences integrated into the plant genome. Results demonstrate that FTA is a practical, economical and sensitive method for sampling, storage and retrieval of viral pathogens and plant genomic sequences, when working under controlled conditions and in the field. Application of this technology has the potential to significantly increase ability to bring modern analytical techniques to bear on the viral pathogens infecting crop plants.

Quantitative polymerase chain reaction (PCR) for detection of aquatic animal pathogens in a diagnostic laboratory setting

USGS Publications Warehouse

Purcell, Maureen K.; Getchell, Rodman G.; McClure, Carol A.; Weber, S.E.; Garver, Kyle A.

2011-01-01

Real-time, or quantitative, polymerase chain reaction (qPCR) is quickly supplanting other molecular methods for detecting the nucleic acids of human and other animal pathogens owing to the speed and robustness of the technology. As the aquatic animal health community moves toward implementing national diagnostic testing schemes, it will need to evaluate how qPCR technology should be employed. This review outlines the basic principles of qPCR technology, considerations for assay development, standards and controls, assay performance, diagnostic validation, implementation in the diagnostic laboratory, and quality assurance and control measures. These factors are fundamental for ensuring the validity of qPCR assay results obtained in the diagnostic laboratory setting.

Pathogen inactivation of human serum facilitates its clinical use for islet cell culture and subsequent transplantation.

PubMed

Ståhle, Magnus U; Brandhorst, Daniel; Korsgren, Olle; Knutson, Folke

2011-01-01

Serum is regarded as an essential supplement to promote survival and growth of cells during culture. However, the potential risk of transmitting diseases disqualifies the use of serum for clinical cell therapy in most countries. Hence, most clinical cell therapy programs have replaced human serum with human serum albumin, which can result in inferior quality of released cell products. Photochemical treatment of different blood products utilizing Intercept® technology has been shown to inactivate a broad variety of pathogens of RNA and DNA origin. The present study assesses the feasibility of using pathogen-inactivated, blood group-compatible serum for use in human pancreatic islet culture. Isolated human islets were cultured at 37°C for 3-4 days in CMRL 1066 supplemented with 10% of either pathogen-inactivated or nontreated human serum. Islet quality assessment included glucose-stimulated insulin release (perifusion), ADP/ATP ratio, cytokine expression, and posttransplant function in diabetic nude mice. No differences were found between islets cultured in pathogen-inactivated or control serum regarding stimulated insulin release, intracellular insulin content, and ADP/ATP ratio. Whether media was supplemented with treated or nontreated serum, islet expression of IL-6, IL-8, MCP-1, or tissue factor was not affected. The final diabetes-reversal rate of mice receiving islets cultured in pathogen-inactivated or nontreated serum was 78% and 87%, respectively (NS). As reported here, pathogen-inactivated human serum does not affect viability or functional integrity of cultured human islets. The implementation of this technology for RNA- and DNA-based pathogen inactivation should enable reintroduction of human serum for clinical cell therapy.

40 CFR 430.114 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2010 CFR

2010-07-01

... degree of effluent reduction attainable by the application of the best available technology economically... effluent reduction attainable by the application of the best available technology economically achievable... representing the degree of effluent reduction attainable by the application of the best available technology...

40 CFR 430.112 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2010 CFR

2010-07-01

... degree of effluent reduction attainable by the application of the best practicable control technology... effluent reduction attainable by the application of the best practicable control technology currently... reduction attainable by the application of the best practicable control technology currently available (BPT...

GENERIC VERIFICATION PROTOCOL FOR DETERMINATION OF EMISSIONS REDUCTIONS FROM SELECTIVE CATALYTIC REDUCTIONS CONTROL TECHNOLOGIES FOR HIGHWAY, NONROAD, AND STATIONARY USE DIESEL ENGINES

EPA Science Inventory

The protocol describes the Environmental Technology Verification (ETV) Program's considerations and requirements for verification of emissions reduction provided by selective catalytic reduction (SCR) technologies. The basis of the ETV will be comparison of the emissions and perf...

40 CFR 440.102 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2013 CFR

2013-07-01

... degree of effluent reduction attainable by the application of the best practicable control technology... degree of effluent reduction attainable by the application of the best practicable control technology... degree of effluent reduction attainable by the application of the best practicable control technology...

40 CFR 440.82 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2010 CFR

2010-07-01

... degree of effluent reduction attainable by the application of the best practicable control technology... effluent reduction attainable by the application of the best practicable control technology currently... degree of effluent reduction attainable by the application of the best practicable control technology...

40 CFR 440.82 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2011 CFR

2011-07-01

... degree of effluent reduction attainable by the application of the best practicable control technology... effluent reduction attainable by the application of the best practicable control technology currently... degree of effluent reduction attainable by the application of the best practicable control technology...

40 CFR 430.112 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2011 CFR

2011-07-01

... degree of effluent reduction attainable by the application of the best practicable control technology... effluent reduction attainable by the application of the best practicable control technology currently... reduction attainable by the application of the best practicable control technology currently available (BPT...

40 CFR 430.114 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2011 CFR

2011-07-01

... degree of effluent reduction attainable by the application of the best available technology economically... effluent reduction attainable by the application of the best available technology economically achievable... representing the degree of effluent reduction attainable by the application of the best available technology...

Automatic Classification of Cellular Expression by Nonlinear Stochastic Embedding (ACCENSE).

PubMed

Shekhar, Karthik; Brodin, Petter; Davis, Mark M; Chakraborty, Arup K

2014-01-07

Mass cytometry enables an unprecedented number of parameters to be measured in individual cells at a high throughput, but the large dimensionality of the resulting data severely limits approaches relying on manual "gating." Clustering cells based on phenotypic similarity comes at a loss of single-cell resolution and often the number of subpopulations is unknown a priori. Here we describe ACCENSE, a tool that combines nonlinear dimensionality reduction with density-based partitioning, and displays multivariate cellular phenotypes on a 2D plot. We apply ACCENSE to 35-parameter mass cytometry data from CD8(+) T cells derived from specific pathogen-free and germ-free mice, and stratify cells into phenotypic subpopulations. Our results show significant heterogeneity within the known CD8(+) T-cell subpopulations, and of particular note is that we find a large novel subpopulation in both specific pathogen-free and germ-free mice that has not been described previously. This subpopulation possesses a phenotypic signature that is distinct from conventional naive and memory subpopulations when analyzed by ACCENSE, but is not distinguishable on a biaxial plot of standard markers. We are able to automatically identify cellular subpopulations based on all proteins analyzed, thus aiding the full utilization of powerful new single-cell technologies such as mass cytometry.

Inactivation of Staphylococcus aureus and native microflora in human milk by high pressure processing

NASA Astrophysics Data System (ADS)

Windyga, Bożena; Rutkowska, Małgorzata; Sokołowska, Barbara; Skąpska, Sylwia; Wesołowska, Aleksandra; Wilińska, Maria; Fonberg-Broczek, Monika; Rzoska, Sylwester J.

2015-04-01

The storage of unpreserved food, including breast milk, is associated with the growth of microorganisms, including pathogenic bacteria. It is therefore necessary to use suitable processes to eliminate pathogenic microorganisms and reduce the total microbial count in order to ensure product safety for consumers. In the present study, samples of milk obtained from volunteers donating to the human milk bank were artificially contaminated with Staphylococcus aureus ATCC 6538. This bacteria was the model microorganism of choice, being relatively resistant to high pressure as well as posing the most serious risk to infant health. The results obtained show that high pressure processing can reduce the count of S. aureus by about 5 log units at 4°C and about 8 log units at 50°C, and totally eliminate Enterobacteriaceae after 5 min of treatment, and result in a total microbial count reduction after 10 min treatment at 500 MPa at 20°C and 50°C. This suggests the possibility of this technology being applied to ensure the adequate safety and quality of human breast milk in human milk banks. This paper was presented at the LIIth European High Pressure Research Group (EHPRG 52) Meeting in Lyon (France), 7-12 September 2014.

Redox proteomics of tomato in response to Pseudomonas syringae infection

PubMed Central

Balmant, Kelly Mayrink; Parker, Jennifer; Yoo, Mi-Jeong; Zhu, Ning; Dufresne, Craig; Chen, Sixue

2015-01-01

Unlike mammals with adaptive immunity, plants rely on their innate immunity based on pattern-triggered immunity (PTI) and effector-triggered immunity (ETI) for pathogen defense. Reactive oxygen species, known to play crucial roles in PTI and ETI, can perturb cellular redox homeostasis and lead to changes of redox-sensitive proteins through modification of cysteine sulfhydryl groups. Although redox regulation of protein functions has emerged as an important mechanism in several biological processes, little is known about redox proteins and how they function in PTI and ETI. In this study, cysTMT proteomics technology was used to identify similarities and differences of protein redox modifications in tomato resistant (PtoR) and susceptible (prf3) genotypes in response to Pseudomonas syringae pv tomato (Pst) infection. In addition, the results of the redox changes were compared and corrected with the protein level changes. A total of 90 potential redox-regulated proteins were identified with functions in carbohydrate and energy metabolism, biosynthesis of cysteine, sucrose and brassinosteroid, cell wall biogenesis, polysaccharide/starch biosynthesis, cuticle development, lipid metabolism, proteolysis, tricarboxylic acid cycle, protein targeting to vacuole, and oxidation–reduction. This inventory of previously unknown protein redox switches in tomato pathogen defense lays a foundation for future research toward understanding the biological significance of protein redox modifications in plant defense responses. PMID:26504582

FROM CONCEPT TO EQUIVALENCY: THE 503 REGULATIONS AND THE PATHOGEN EQUIVALENCY COMMITTEE (PAPER)

EPA Science Inventory

Since its creation in 1985, the Pathogen Equivalency Committee (PEC) has been reviewing innovative and alternative sludge disinfection technologies with regards to their abilities to protect human health and the environment. The PEC is charged to make recommendations on whether t...

EVALUATION OF RAPID, QUANTITATIVE REAL-TIME PCR METHOD FOR ENUMERATION OF PATHOGENIC CANDIDA CELLS IN WATER

EPA Science Inventory

Quantitative Real-Time PCR (QRT-PCR) technology, incorporating fluorigenic 5' nuclease (TaqMan (trademark)) chemistry, was developed for the specific detection and quantification of six pathogenic species of Candida (C. albicans, C. tropicalis, C. krusei, C. parapsilosis, C. glab...

Bacteriophage remediation of bacterial pathogens in aquaculture: a review of the technology

USDA-ARS?s Scientific Manuscript database

Bacteriophages have been proposed as an alternative to antibiotic usage and several studies on their application in aquaculture have been reported. This review highlights progress to date on phage therapies for the following fish and shellfish diseases and associated pathogens: hemorrhagic septicem...

Detection of foodborne pathogens using microarray technology

USDA-ARS?s Scientific Manuscript database

Assays based on the polymerase chain reaction (PCR) are now accepted methods for rapidly confirming the presence or absence of specific pathogens in foods and other types of samples. Conventional PCR requires the use of agarose gel electrophoresis to detect the PCR product; whereas, real-time PCR c...

40 CFR 503.17 - Recordkeeping.

Code of Federal Regulations, 2011 CFR

2011-07-01

... in § 503.32(a) and the vector attraction reduction requirement in [insert one of the vector attraction reduction requirements in § 503.33(b)(1) through § 503.33(b)(8)] was prepared under my direction... pathogen requirements in § 503.32(a) are met. (iv) A description of how one of the vector attraction...

Generic aspects of the airborne spread of human pathogens indoors and emerging air decontamination technologies.

PubMed

Ijaz, M Khalid; Zargar, Bahram; Wright, Kathryn E; Rubino, Joseph R; Sattar, Syed A

2016-09-02

Indoor air can be an important vehicle for a variety of human pathogens. This review provides examples of airborne transmission of infectious agents from experimental and field studies and discusses how airborne pathogens can contaminate other parts of the environment to give rise to secondary vehicles leading air-surface-air nexus with possible transmission to susceptible hosts. The following groups of human pathogens are covered because of their known or potential airborne spread: vegetative bacteria (staphylococci and legionellae), fungi (Aspergillus, Penicillium, and Cladosporium spp and Stachybotrys chartarum), enteric viruses (noro- and rotaviruses), respiratory viruses (influenza and coronaviruses), mycobacteria (tuberculous and nontuberculous), and bacterial spore formers (Clostridium difficile and Bacillus anthracis). An overview of methods for experimentally generating and recovering airborne human pathogens is included, along with a discussion of factors that influence microbial survival in indoor air. Available guidelines from the U.S. Environmental Protection Agency and other global regulatory bodies for the study of airborne pathogens are critically reviewed with particular reference to microbial surrogates that are recommended. Recent developments in experimental facilities to contaminate indoor air with microbial aerosols are presented, along with emerging technologies to decontaminate indoor air under field-relevant conditions. Furthermore, the role that air decontamination may play in reducing the contamination of environmental surfaces and its combined impact on interrupting the risk of pathogen spread in both domestic and institutional settings is discussed. Copyright © 2016. Published by Elsevier Inc.

Safety of foods treated with novel process intervention technologies

USDA-ARS?s Scientific Manuscript database

Many consumers are familiar with traditional food safety and preservation technologies such as thermal processing (cooking), salting, and pickling to inactivate common foodborne pathogens such as Salmonella spp. and Escherichia coli O157:H7. Many consumers are less familiar with other technologies s...

Two pathogenic species of Pythium: P. aphanidermatum and P. diclinum from a wheat field.

PubMed

Al-Sheikh, Hashem

2010-10-01

During a survey of pathogenic and non-pathogenic Pythium spp. in different localities in Egypt, several isolates of Pythia were obtained and maintained on corn meal agar. Among these isolates, Pythium aphanidermatum and Pythium diclinum were obtained from rhizosphere of wheat plants grown in Dear Attia village, Minia, Egypt. Identification was made using morphological and molecular analyses. P. aphanidermatum and P. diclinum were able to cause reductions in emergence and adulating in wheat in laboratory scale. P. aphanidermatum appeared to be the most aggressive parasite under agar and pot experimental conditions.

Two pathogenic species of Pythium: P. aphanidermatum and P. diclinum from a wheat field

PubMed Central

Al-Sheikh, Hashem

2010-01-01

During a survey of pathogenic and non-pathogenic Pythium spp. in different localities in Egypt, several isolates of Pythia were obtained and maintained on corn meal agar. Among these isolates, Pythium aphanidermatum and Pythium diclinum were obtained from rhizosphere of wheat plants grown in Dear Attia village, Minia, Egypt. Identification was made using morphological and molecular analyses. P. aphanidermatum and P. diclinum were able to cause reductions in emergence and adulating in wheat in laboratory scale. P. aphanidermatum appeared to be the most aggressive parasite under agar and pot experimental conditions. PMID:23961096

Opportunities for mitigating pathogen contamination during on-farm food production.

PubMed

Doyle, Michael P; Erickson, Marilyn C

2012-01-16

Fruits, vegetables, and meat are susceptible to contamination by foodborne pathogens at many points from production through preparation in the home. This review will largely highlight approaches and progress made in the last five years to address strategies to reduce pathogen contamination in animal production but will also touch on the emerging field of preharvest produce food safety. Mitigation strategies can be divided into those that address pathogen reduction in the environment and those that target reduction/elimination of pathogen contamination in animals or plants. The former strategy has been encompassed in studies evaluating sanitation treatments of facilities as well as in numerous epidemiologic risk assessment studies (both on-farm assessments and computer simulation models) that identify management practices that impact pathogen prevalence in animals. Interventions to significantly reduce pathogen exposure via feed or water are dependent on their role as a significant contributor to pathogen contamination in the animal production system. In addition, inconsistent results obtained with interventions of dietary additives or formulation modifications (grain versus forage; inclusion of distiller's grains) on pathogen prevalence in animals have been attributed to a range of factors including target organism, grain type, level of inclusion, the animal's health or stress level, and ability to survive the gastric acidic conditions. Recent attempts to microencapsulate organic acids or bacteriophage within feed have met with only marginal improvements in reducing pathogen carriage in animals but this approach may have greater potential with other antimicrobial additives (i.e., essential oils). Bacteriophage therapy, in general, can significantly reduce pathogen carriage in animals but based on its transient nature and the potential for development of phage-resistant subpopulations, this approach should be administered to animals just prior to slaughter and preferably to animals that are suspected "super-shedders". Other promising on-farm intervention approaches have included breeding for pathogen resistance, vaccines, and dietary bacteriocins. To optimize interventions on a cost basis, studies have also determined that application of dietary interventions at specific time points in the animal's production cycle is a useful strategy to reduce pathogen carriage (e.g., probiotics to fertilized eggs and acidified feed to fattening swine). In conclusion, applicable management and intervention strategies may vary depending on the type of food under production; however, it is important to consider from a holistic view how any new intervention strategies will affect the overall production system in order to maintain a successful, efficient food production environment. Copyright © 2011 Elsevier B.V. All rights reserved.

Technologies for Aircraft Noise Reduction

NASA Technical Reports Server (NTRS)

Huff, Dennis L.

2006-01-01

Technologies for aircraft noise reduction have been developed by NASA over the past 15 years through the Advanced Subsonic Technology (AST) Noise Reduction Program and the Quiet Aircraft Technology (QAT) project. This presentation summarizes highlights from these programs and anticipated noise reduction benefits for communities surrounding airports. Historical progress in noise reduction and technologies available for future aircraft/engine development are identified. Technologies address aircraft/engine components including fans, exhaust nozzles, landing gear, and flap systems. New "chevron" nozzles have been developed and implemented on several aircraft in production today that provide significant jet noise reduction. New engines using Ultra-High Bypass (UHB) ratios are projected to provide about 10 EPNdB (Effective Perceived Noise Level in decibels) engine noise reduction relative to the average fleet that was flying in 1997. Audio files are embedded in the presentation that estimate the sound levels for a 35,000 pound thrust engine for takeoff and approach power conditions. The predictions are based on actual model scale data that was obtained by NASA. Finally, conceptual pictures are shown that look toward future aircraft/propulsion systems that might be used to obtain further noise reduction.

Biopreservative methods to control the growth of foodborne pathogens on fresh-cut lettuce.

PubMed

Oliveira, M; Abadias, M; Colás-Medà, P; Usall, J; Viñas, I

2015-12-02

Fruits and vegetables can become contaminated by foodborne pathogens such as Escherichia coli O157:H7, Salmonella and Listeria monocytogenes, and it has been demonstrated that current industrial sanitizing treatments do not eliminate the pathogens when present. Chemical control is widely used, but biological control appears to be a better solution, mainly using the native microbiota present on fresh produce. The first objective of this study was to isolate native microbiota from whole and fresh-cut produce and to determine whether these bacteria were antagonistic toward foodborne pathogens. A total of 112 putative antagonist isolates were screened for their ability to inhibit the growth of Salmonella enterica on lettuce disks. Five different genera reduced S. enterica growth more than 1-log unit at 20°C at the end of 3 days. When tested against L. monocytogenes 230/3, only Pseudomonas sp. strain M309 (M309) was able to reduce pathogen counts by more than 1-log unit. Therefore, M309 strain was selected to be tested on lettuce disks at 10°C against S. enterica, E. coli O157:H7 and L. monocytogenes. M309 strain was only able to reduce S. enterica and E. coli O157:H7 populations. The second objective was to test different biopreservative methods including M309 strain, Pseudomonas graminis CPA-7 (CPA-7), bacteriophages (Listex P100 and Salmonelex) and nisin at conditions simulating commercial applications against Salmonella and L. monocytogenes on fresh-cut lettuce. The addition of the biopreservative agents did not result in a significant reduction of Salmonella population. However, CPA-7 strain together with nisin reduced L. monocytogenes numbers after 6 days of storage at 10°C. The cocktail of Salmonella and L. monocytogenes was not markedly inactivated by their respective bacteriophage solutions. This study highlighted the potential of biocontrol, but the combination with other technologies may be required to improve their application on fresh-cut lettuce. Copyright © 2015 Elsevier B.V. All rights reserved.

Pathogen-reduced platelets for the prevention of bleeding

PubMed Central

Estcourt, Lise J; Malouf, Reem; Hopewell, Sally; Trivella, Marialena; Doree, Carolyn; Stanworth, Simon J; Murphy, Michael F

2017-01-01

Background Platelet transfusions are used to prevent and treat bleeding in people who are thrombocytopenic. Despite improvements in donor screening and laboratory testing, a small risk of viral, bacterial, or protozoal contamination of platelets remains. There is also an ongoing risk from newly emerging blood transfusion-transmitted infections for which laboratory tests may not be available at the time of initial outbreak. One solution to reduce the risk of blood transfusion-transmitted infections from platelet transfusion is photochemical pathogen reduction, in which pathogens are either inactivated or significantly depleted in number, thereby reducing the chance of transmission. This process might offer additional benefits, including platelet shelf-life extension, and negate the requirement for gamma-irradiation of platelets. Although current pathogen-reduction technologies have been proven to reduce pathogen load in platelet concentrates, a number of published clinical studies have raised concerns about the effectiveness of pathogen-reduced platelets for post-transfusion platelet count recovery and the prevention of bleeding when compared with standard platelets. This is an update of a Cochrane review first published in 2013. Objectives To assess the effectiveness of pathogen-reduced platelets for the prevention of bleeding in people of any age requiring platelet transfusions. Search methods We searched for randomised controlled trials (RCTs) in the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library 2016, Issue 9), MEDLINE (from 1946), Embase (from 1974), CINAHL (from 1937), the Transfusion Evidence Library (from 1950), and ongoing trial databases to 24 October 2016. Selection criteria We included RCTs comparing the transfusion of pathogen-reduced platelets with standard platelets, or comparing different types of pathogen-reduced platelets. Data collection and analysis We used the standard methodological procedures expected by Cochrane. Main results We identified five new trials in this update of the review. A total of 15 trials were eligible for inclusion in this review, 12 completed trials (2075 participants) and three ongoing trials. Ten of the 12 completed trials were included in the original review. We did not identify any RCTs comparing the transfusion of one type of pathogen-reduced platelets with another. Nine trials compared Intercept® pathogen-reduced platelets to standard platelets, two trials compared Mirasol® pathogen-reduced platelets to standard platelets; and one trial compared both pathogen-reduced platelets types to standard platelets. Three RCTs were randomised cross-over trials, and nine were parallel-group trials. Of the 2075 participants enrolled in the trials, 1981 participants received at least one platelet transfusion (1662 participants in Intercept® platelet trials and 319 in Mirasol® platelet trials). One trial included children requiring cardiac surgery (16 participants) or adults requiring a liver transplant (28 participants). All of the other participants were thrombocytopenic individuals who had a haematological or oncological diagnosis. Eight trials included only adults. Four of the included studies were at low risk of bias in every domain, while the remaining eight included studies had some threats to validity. Overall, the quality of the evidence was low to high across different outcomes according to GRADE methodology. We are very uncertain as to whether pathogen-reduced platelets increase the risk of any bleeding (World Health Organization (WHO) Grade 1 to 4) (5 trials, 1085 participants; fixed-effect risk ratio (RR) 1.09, 95% confidence interval (CI) 1.02 to 1.15; I2 = 59%, random-effect RR 1.14, 95% CI 0.93 to 1.38; I2 = 59%; low-quality evidence). There was no evidence of a difference between pathogen-reduced platelets and standard platelets in the incidence of clinically significant bleeding complications (WHO Grade 2 or higher) (5 trials, 1392 participants; RR 1.10, 95% CI 0.97 to 1.25; I2 = 0%; moderate-quality evidence), and there is probably no difference in the risk of developing severe bleeding (WHO Grade 3 or higher) (6 trials, 1495 participants; RR 1.24, 95% CI 0.76 to 2.02; I2 = 32%; moderate-quality evidence). There is probably no difference between pathogen-reduced platelets and standard platelets in the incidence of all-cause mortality at 4 to 12 weeks (6 trials, 1509 participants; RR 0.81, 95% CI 0.50 to 1.29; I2 = 26%; moderate-quality evidence). There is probably no difference between pathogen-reduced platelets and standard platelets in the incidence of serious adverse events (7 trials, 1340 participants; RR 1.09, 95% CI 0.88 to 1.35; I2 = 0%; moderate-quality evidence). However, no bacterial transfusion-transmitted infections occurred in the six trials that reported this outcome. Participants who received pathogen-reduced platelet transfusions had an increased risk of developing platelet refractoriness (7 trials, 1525 participants; RR 2.94, 95% CI 2.08 to 4.16; I2 = 0%; high-quality evidence), though the definition of platelet refractoriness differed between trials. Participants who received pathogen-reduced platelet transfusions required more platelet transfusions (6 trials, 1509 participants; mean difference (MD) 1.23, 95% CI 0.86 to 1.61; I2 = 27%; high-quality evidence), and there was probably a shorter time interval between transfusions (6 trials, 1489 participants; MD -0.42, 95% CI -0.53 to -0.32; I2 = 29%; moderate-quality evidence). Participants who received pathogen-reduced platelet transfusions had a lower 24-hour corrected-count increment (7 trials, 1681 participants; MD -3.02, 95% CI -3.57 to -2.48; I2 = 15%; high-quality evidence). None of the studies reported quality of life. We did not evaluate any economic outcomes. There was evidence of subgroup differences in multiple transfusion trials between the two pathogen-reduced platelet technologies assessed in this review (Intercept® and Mirasol®) for all-cause mortality and the interval between platelet transfusions (favouring Intercept®). Authors' conclusions Findings from this review were based on 12 trials, and of the 1981 participants who received a platelet transfusion only 44 did not have a haematological or oncological diagnosis. In people with haematological or oncological disorders who are thrombocytopenic due to their disease or its treatment, we found high-quality evidence that pathogen-reduced platelet transfusions increase the risk of platelet refractoriness and the platelet transfusion requirement. We found moderate-quality evidence that pathogen-reduced platelet transfusions do not affect all-cause mortality, the risk of clinically significant or severe bleeding, or the risk of a serious adverse event. There was insufficient evidence for people with other diagnoses. All three ongoing trials are in adults (planned recruitment 1375 participants) with a haematological or oncological diagnosis. PMID:28756627

EVALUATION OF A RAPID, QUANTITATIVE REAL-TIME PCR METHOD FOR ENUMERATION OF PATHOGENIC CANDIDA CELLS IN WATER

EPA Science Inventory

Quantitative Real-Time PCR (QRT-PCR) technology, incorporating fluorigenic 5' nuclease (TaqMan?) chemistry, was developed for the specific detection and quantification of six pathogenic species of Candida (C. albicans, C. tropicalis, C. krusei, C. parapsilosis, C. glabrata and C....

Preliminary research concerning the use of electron accelerators to improve the conservability and to extend the shelf-life of fruits and vegetables

NASA Astrophysics Data System (ADS)

Minea, R.; Oproiu, C.; Pascanu, S.; Matei, C.; Ferdes, O.

1996-06-01

The potential of ionizing radiation treatment for food preservation, shelf-life extension, control of microbial load and reduction of pathogenic microorganism was demonstrated. The irradiations were performed under normal conditions on the Institute of Physics and Technology for Radiation Device's linear electron accelerator, which has the following parameters: 5 μA mean beam current, 6 MeV electron mean energy, pulse period 3.5 μs and dose rates between 100-1500 Gy/min. This research project was aimed at assuring the consumer's acceptance for radiation-treated food and to obtain a significant reduction of food losses. We also propose a promising solution for the radiation processing of some bulk food products at the place of storage, consisting of a mobile electron accelerator. The main characteristics of the mobile electron accelerator are: electron energy 3 to 5 MeV, maximum beam power 5 kW, vertical electron beam; irradiation is possible both with electron beams and with bremsstrahlung. The results of our preliminary research lead to the conclusion that electron-beam irradiation and the use of electron accelerators is a promising solution for food preservation and food safety. Interesting future applications are outlined.

Prevention of infections in an ART laboratory: a reflection on simplistic methods.

PubMed

Huyser, C

2014-01-01

Preventative measures combined with reactive remedial actions are generic management tools to optimize and protect an entity's core businesses. Differences between assisted reproduction technology (ART) laboratories in developing versus developed countries include restricted access to, or availability of resources, and the prevalence of pathological conditions that are endemic or common in non-industrialized regions. The aim of this paper is to discuss the prevention of infections in an ART laboratory in a low to middle-income country, with reference to simplistic risk reduction applications to avoid the introduction and transmission of pathogens. Diagnostic and procedural phases will be examined, i.e. (i) screening for microbes during patient evaluation, and (ii-iii) prevention of environmental and procedural contamination. Preventative action is enabled by knowledge of threats and the degree of risk involved. Awareness and understanding of the vulnerabilities in an ART system, wherein laboratory personnel operate, are invaluable assets when unforeseen equipment failure occurs or instant decisions have to be made to safeguard procedures. An inter-connective team approach to patient treatment, biosafety training and utilization of practical procedures such as semen decontamination, are fundamental tools in a laboratory's risk-reduction armoury to prevent and eliminate infectious elements.

Pulsed-plasma gas-discharge inactivation of microbial pathogens in chilled poultry wash water.

PubMed

Rowan, N J; Espie, S; Harrower, J; Anderson, J G; Marsili, L; MacGregor, S J

2007-12-01

A pulsed-plasma gas-discharge (PPGD) system was developed for the novel decontamination of chilled poultry wash water. Treatment of poultry wash water in the plasma generation chamber for up to 24 s at 4 degrees C reduced Escherichia coli NCTC 9001, Campylobacter jejuni ATCC 33560, Campylobacter coli ATCC 33559, Listeria monocytogenes NCTC 9863, Salmonella enterica serovar Enteritidis ATCC 4931, and S. enterica serovar Typhimurium ATCC 14028 populations to non-detectable levels (< or = 8 log CFU/ml). Although similar PPGD treatments at 4 degrees C also produced significant reductions (> or = 3 log CFU/ml) in recalcitrant B. cereus NCTC 11145 endospore numbers within 30 s, the level of endospore reduction was dependent on the nature of the sparged gas used in the plasma treatments. Scanning electron microscopy revealed that significant damage occurred at the cellular level in PPGD-treated test organisms. This electrotechnology delivers energy in intense ultrashort bursts, generating products such as ozone, UV light, acoustic and shock waves, and pulsed electric fields that have multiple bactericidal properties. This technology offers an exciting complementary or alternative approach for treating raw poultry wash water and for preventing cross-contamination in processing environments.

Valuing the subsurface pathogen treatment barrier in water recycling via aquifers for drinking supplies.

PubMed

Page, Declan; Dillon, Peter; Toze, Simon; Bixio, Davide; Genthe, Bettina; Jiménez Cisneros, Blanca Elena; Wintgens, Thomas

2010-03-01

A quantitative microbial risk assessment (QMRA) was performed at four managed aquifer recharge (MAR) sites (Australia, South Africa, Belgium, Mexico) where reclaimed wastewater and stormwater is recycled via aquifers for drinking water supplies, using the same risk-based approach that is used for public water supplies. For each of the sites, the aquifer treatment barrier was assessed for its log(10) removal capacity much like for other water treatment technologies. This information was then integrated into a broader risk assessment to determine the human health burden from the four MAR sites. For the Australian and South African cases, managing the aquifer treatment barrier was found to be critical for the schemes to have low risk. For the Belgian case study, the large treatment trains both in terms of pre- and post-aquifer recharge ensures that the risk is always low. In the Mexico case study, the risk was high due to the lack of pre-treatment and the low residence times of the recharge water in the aquifer. A further sensitivity analysis demonstrated that human health risk can be managed if aquifers are integrated into a treatment train to attenuate pathogens. However, reduction in human health disease burden (as measured in disability adjusted life years, DALYs) varied depending upon the number of pathogens in the recharge source water. The beta-Poisson dose response curve used for translating rotavirus and Cryptosporidium numbers into DALYs coupled with their slow environmental decay rates means poor quality injectant leads to aquifers having reduced value to reduce DALYs. For these systems, like the Mexican case study, longer residence times are required to meet their DALYs guideline for drinking water. Nevertheless the results showed that the risks from pathogens can still be reduced and recharging via an aquifer is safer than discharging directly into surface water bodies. Copyright 2009 Elsevier Ltd. All rights reserved.

Effect of high pressure processing on the survival of Salmonella Enteritidis and shelf-life of chicken fillets.

PubMed

Argyri, Anthoula A; Papadopoulou, Olga S; Nisiotou, Aspasia; Tassou, Chrysoula C; Chorianopoulos, Nikos

2018-04-01

High pressure processing (HPP) is a preservation technology alternative to heat treatment that is mild for food, but effectively inactivates the spoilage microbiota and foodborne pathogens of several foods. The purpose of the current study was to evaluate the effect of HPP on Salmonella ser. Enteritidis, indigenous microbiota and shelf-life of chicken fillets. Chicken fillets were inoculated with S. Enteritidis at three different initial inocula (3, 5, 7 log CFU/g), packed under vacuum, treated or not with HPP (500 MPa/10 min) and stored at 4 and 12 °C. Total viable counts, S. Enteritidis, pseudomonads, Brochothrix thermosphacta, lactic acid bacteria, Enterobacteriaceae and yeasts/molds populations were determined in parallel with sensory analysis of non-inoculated samples. The HPP resulted in the reduction of the pathogen population below the detection limit of the enumeration method (0.48 log CFU/g), irrespective of the inoculum. During the shelf life of the HPP samples, the pathogens population remained below or near the detection limit of the enumeration method at both temperatures, except from the high inoculum case that an increase was observed at 12 °C. At the low inoculum level, the pathogen could not be detected with the enrichment method after the first storage days (2nd day for 4 °C and 0 day for 12 °C). The survival of Salmonella strains was assessed by pulsed field gel electrophoresis and it was shown that the survival of the different strains depended on the inoculum and storage temperature. Regarding the indigenous microbiota, Br. thermosphacta was reported for the first time to be the main spoilage microorganism that survived and dominated after the HPP. From the results it was evident that, HPP may enhance the safety and increase the shelf life (6 at 4 °C and 2 days at 12 °C) of chicken meat. Copyright © 2017 Elsevier Ltd. All rights reserved.

Rapid multiplex detection of 10 foodborne pathogens with an up-converting phosphor technology-based 10-channel lateral flow assay

PubMed Central

Zhao, Yong; Wang, Haoran; Zhang, Pingping; Sun, Chongyun; Wang, Xiaochen; Wang, Xinrui; Yang, Ruifu; Wang, Chengbin; Zhou, Lei

2016-01-01

The rapid high-throughput detection of foodborne pathogens is essential in controlling food safety. In this study, a 10-channel up-converting phosphor technology-based lateral flow (TC-UPT-LF) assay was established for the rapid and simultaneous detection of 10 epidemic foodborne pathogens. Ten different single-target UPT-LF strips were developed and integrated into one TC-UPT-LF disc with optimization. Without enrichment the TC-UPT-LF assay had a detection sensitivity of 104 CFU mL−1 or 105 CFU mL−1 for each pathogen, and after sample enrichment it was 10 CFU/0.6 mg. The assay also showed good linearity, allowing quantitative detection, with a linear fitting coefficient of determination (R2) of 0.916–0.998. The 10 detection channels did not cross-react, so multiple targets could be specifically detected. When 279 real food samples were tested, the assay was highly consistent (100%) with culture-based methods. The results for 110 food samples artificially contaminated with single or multiple targets showed a high detection rate (≥80%) for most target bacteria. Overall, the TC-UPT-LF assay allows the rapid, quantitative, and simultaneous detection of 10 kinds of foodborne pathogens within 20 min, and is especially suitable for the rapid detection and surveillance of foodborne pathogens in food and water. PMID:26884128

Rapid multiplex detection of 10 foodborne pathogens with an up-converting phosphor technology-based 10-channel lateral flow assay.

PubMed

Zhao, Yong; Wang, Haoran; Zhang, Pingping; Sun, Chongyun; Wang, Xiaochen; Wang, Xinrui; Yang, Ruifu; Wang, Chengbin; Zhou, Lei

2016-02-17

The rapid high-throughput detection of foodborne pathogens is essential in controlling food safety. In this study, a 10-channel up-converting phosphor technology-based lateral flow (TC-UPT-LF) assay was established for the rapid and simultaneous detection of 10 epidemic foodborne pathogens. Ten different single-target UPT-LF strips were developed and integrated into one TC-UPT-LF disc with optimization. Without enrichment the TC-UPT-LF assay had a detection sensitivity of 10(4) CFU mL(-1) or 10(5) CFU mL(-1) for each pathogen, and after sample enrichment it was 10 CFU/0.6 mg. The assay also showed good linearity, allowing quantitative detection, with a linear fitting coefficient of determination (R(2)) of 0.916-0.998. The 10 detection channels did not cross-react, so multiple targets could be specifically detected. When 279 real food samples were tested, the assay was highly consistent (100%) with culture-based methods. The results for 110 food samples artificially contaminated with single or multiple targets showed a high detection rate (≥ 80%) for most target bacteria. Overall, the TC-UPT-LF assay allows the rapid, quantitative, and simultaneous detection of 10 kinds of foodborne pathogens within 20 min, and is especially suitable for the rapid detection and surveillance of foodborne pathogens in food and water.

Pathogenic Gene Screening of Mycobacterium tuberculosis by Literature Data Mining and Information Pathway Enrichment Analysis.

PubMed

Xu, Guangyu; Wen, Simin; Pan, Yuchen; Zhang, Nan; Wang, Yuanyi

2018-05-01

Recent studies have unraveled mutations which have led to changes in the original conformation of functional proteins targeted by frontline drugs against Mycobacterium tuberculosis. These mutations are likely responsible for the emergence of drug-resistant strains of M. tuberculosis. Identification of new therapeutic targets is fundamental to the development of novel anti-TB drugs. Boost evolution analysis of interactome data with use of high-throughput biological experimental technologies provides opportunities for identification of pathogenic genes and for screening out novel therapeutic targets. In this study, we identified 584 proven pathogenic genes of M. tuberculosis and new pathogenic genes via bibliometrics and relevant websites such as PubMed, KEGG, and DOOR websites. We identified 13 new genes that are most likely to be pathogenic. This study may contribute to the discovery of new pathogenic genes and help unravel new functions of known pathogenic genes of M. tuberculosis.

Current Technical Approaches for the Early Detection of Foodborne Pathogens: Challenges and Opportunities.

PubMed

Cho, Il-Hoon; Ku, Seockmo

2017-09-30

The development of novel and high-tech solutions for rapid, accurate, and non-laborious microbial detection methods is imperative to improve the global food supply. Such solutions have begun to address the need for microbial detection that is faster and more sensitive than existing methodologies (e.g., classic culture enrichment methods). Multiple reviews report the technical functions and structures of conventional microbial detection tools. These tools, used to detect pathogens in food and food homogenates, were designed via qualitative analysis methods. The inherent disadvantage of these analytical methods is the necessity for specimen preparation, which is a time-consuming process. While some literature describes the challenges and opportunities to overcome the technical issues related to food industry legal guidelines, there is a lack of reviews of the current trials to overcome technological limitations related to sample preparation and microbial detection via nano and micro technologies. In this review, we primarily explore current analytical technologies, including metallic and magnetic nanomaterials, optics, electrochemistry, and spectroscopy. These techniques rely on the early detection of pathogens via enhanced analytical sensitivity and specificity. In order to introduce the potential combination and comparative analysis of various advanced methods, we also reference a novel sample preparation protocol that uses microbial concentration and recovery technologies. This technology has the potential to expedite the pre-enrichment step that precedes the detection process.

Modeling the survival of Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella Typhimurium during fermentation, drying, and storage of soudjouk-style fermented sausage.

PubMed

Hwang, Cheng-An; Porto-Fett, Anna C S; Juneja, Vijay K; Ingham, Steven C; Ingham, Barbara H; Luchansky, John B

2009-02-28

This study quantified and modeled the survival of Escherichia coli O157:H7, Listeria monocytogenes and Salmonella Typhimurium in soudjouk-style fermented sausage during fermentation, drying, and storage. Batter prepared from ground beef (20% fat), seasonings, starter culture, and dextrose was separately inoculated with a multi-strain mixture of each pathogen to an initial inoculum of ca. 6.5 log(10) CFU/g in the batter. The sausages were subsequently fermented at 24 degrees C with a relative humidity (RH) of 90% to 95% for 3 to 5 days to ca. pH 5.2, pH 4.9 or pH 4.6, then dried at 22 degrees C to a(w) 0.92, a(w) 0.89, or a(w) 0.86, respectively, and then stored at 4, 21, or 30 degrees C for up to 60 days. Lethality of the three pathogens was modeled as a function of pH, a(w) and/or storage temperature. During fermentation to pH 5.2 to pH 4.6, cell reductions ranged from 0 to 0.9 log(10) CFU/g for E. coli O157:H7, 0.1 to 0.5 log(10) CFU/g for L. monocytogenes, and 0 to 2.2 log(10) CFU/g for S. Typhimurium. Subsequent drying of sausages of pH 5.2 to pH 4.6 at 22 degrees C with 80% to 85% RH for 3 to 7 days to a(w) of 0.92 to a(w) 0.86 resulted in additional reductions that ranged from 0 to 3.5 log(10) CFU/g for E. coli O157:H7, 0 to 0.4 log(10) CFU/g for L. monocytogenes, and 0.3 to 2.4 log(10) CFU/g for S. Typhimurium. During storage at 4, 21, or 30 degrees C the reduction rates of the three pathogens were generally higher (p<0.05) in sausages with lower pH and lower a(w) that were stored at higher temperatures. Polynomial equations were developed to describe the inactivation of the three pathogens during fermentation, drying, and storage. The applicability of the resulting models for fermented sausage was evaluated by comparing model predictions with published data. Pathogen reductions estimated by the models for E. coli O157:H7 and S. Typhimurium were comparable to 67% and 73% of published data, respectively. Due to limited published data for L. monocytogenes, the models for L. monocytogenes would need additional validations. Results of pathogen reductions from this study may be used as a reference to assist manufacturers of soudjouk-style sausages to adopt manufacturing processes that meet the regulatory requirements. The resulting models may also be used for estimating the survival of E. coli O157:H7 and S. Typhimurium in other similar fermented sausage during fermentation and storage.

Application of Proteomics for the Investigation of the Effect of Initial pH on Pathogenic Mechanisms of Fusarium proliferatum on Banana Fruit.

PubMed

Li, Taotao; Wu, Qixian; Wang, Yong; John, Afiya; Qu, Hongxia; Gong, Liang; Duan, Xuewu; Zhu, Hong; Yun, Ze; Jiang, Yueming

2017-01-01

Fusarium proliferatum is an important pathogen and causes a great economic loss to fruit industry. Environmental pH-value plays a regulatory role in fungi pathogenicity, however, the mechanism needs further exploration. In this study, F. proliferatum was cultured under two initial pH conditions of 5 and 10. No obvious difference was observed in the growth rate of F. proliferatum between two pH-values. F. proliferatum cultured under both pH conditions infected banana fruit successfully, and smaller lesion diameter was presented on banana fruit inoculated with pH 10-cultured fungi. Proteomic approach based on two-dimensional electrophoresis (2-DE) was used to investigate the changes in secretome of this fungus between pH 5 and 10. A total of 39 differential spots were identified using matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry (MALDI-TOF/TOF-MS) and liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS). Compared to pH 5 condition, proteins related to cell wall degrading enzymes (CWDEs) and proteolysis were significantly down-regulated at pH 10, while proteins related to oxidation-reduction process and transport were significantly up-regulated under pH 10 condition. Our results suggested that the downregulation of CWDEs and other virulence proteins in the pH 10-cultured F. proliferatum severely decreased its pathogenicity, compared to pH 5-cultured fungi. However, the alkaline environment did not cause a complete loss of the pathogenic ability of F. proliferatum , probably due to the upregulation of the oxidation-reduction related proteins at pH 10, which may partially compensate its pathogenic ability.

WASTE REDUCTION OF TECHNOLOGY EVALUATIONS OF THE U.S. EPA WRITE PROGRAM

EPA Science Inventory

The Waste Reduction Innovative Technology Evaluation (WRITE)Program was established in 1989 to provide objective, accurate performance and cost data about waste reducing technologies for a variety of industrial and commercial application. EPA's Risk Reduction Engineering Laborato...

WASTE REDUCTION TECHNOLOGY EVALUATIONS AT THREE PRINTED WIRE BOARD MANUFACTURERS

EPA Science Inventory

Technologies at three printed wire board (PWB) manufacturers were evaluated for waste reduction, and costs were compared to existing operations. rom 1989 to 1993, these evaluations were conducted under US EPA's Waste Reduction Innovative Technology Evaluation (WRITE) Program, in ...

Detection of Intestinal Protozoa in the Clinical Laboratory

PubMed Central

McHardy, Ian H.; Wu, Max; Shimizu-Cohen, Robyn; Couturier, Marc Roger

2014-01-01

Despite recent advances in diagnostic technology, microscopic examination of stool specimens remains central to the diagnosis of most pathogenic intestinal protozoa. Microscopy is, however, labor-intensive and requires a skilled technologist. New, highly sensitive diagnostic methods have been developed for protozoa endemic to developed countries, including Giardia lamblia (syn. G. intestinalis/G. duodenalis) and Cryptosporidium spp., using technologies that, if expanded, could effectively complement or even replace microscopic approaches. To date, the scope of such novel technologies is limited and may not include common protozoa such as Dientamoeba fragilis, Entamoeba histolytica, or Cyclospora cayetanensis. This minireview describes canonical approaches for the detection of pathogenic intestinal protozoa, while highlighting recent developments and FDA-approved tools for clinical diagnosis of common intestinal protozoa. PMID:24197877

Detection of intestinal protozoa in the clinical laboratory.

PubMed

McHardy, Ian H; Wu, Max; Shimizu-Cohen, Robyn; Couturier, Marc Roger; Humphries, Romney M

2014-03-01

Despite recent advances in diagnostic technology, microscopic examination of stool specimens remains central to the diagnosis of most pathogenic intestinal protozoa. Microscopy is, however, labor-intensive and requires a skilled technologist. New, highly sensitive diagnostic methods have been developed for protozoa endemic to developed countries, including Giardia lamblia (syn. G. intestinalis/G. duodenalis) and Cryptosporidium spp., using technologies that, if expanded, could effectively complement or even replace microscopic approaches. To date, the scope of such novel technologies is limited and may not include common protozoa such as Dientamoeba fragilis, Entamoeba histolytica, or Cyclospora cayetanensis. This minireview describes canonical approaches for the detection of pathogenic intestinal protozoa, while highlighting recent developments and FDA-approved tools for clinical diagnosis of common intestinal protozoa.

Optimization of Multiple Pathogen Detection Using the TaqMan Array Card: Application for a Population-Based Study of Neonatal Infection

PubMed Central

Diaz, Maureen H.; Waller, Jessica L.; Napoliello, Rebecca A.; Islam, Md. Shahidul; Wolff, Bernard J.; Burken, Daniel J.; Holden, Rhiannon L.; Srinivasan, Velusamy; Arvay, Melissa; McGee, Lesley; Oberste, M. Steven; Whitney, Cynthia G.; Schrag, Stephanie J.; Winchell, Jonas M.; Saha, Samir K.

2013-01-01

Identification of etiology remains a significant challenge in the diagnosis of infectious diseases, particularly in resource-poor settings. Viral, bacterial, and fungal pathogens, as well as parasites, play a role for many syndromes, and optimizing a single diagnostic system to detect a range of pathogens is challenging. The TaqMan Array Card (TAC) is a multiple-pathogen detection method that has previously been identified as a valuable technique for determining etiology of infections and holds promise for expanded use in clinical microbiology laboratories and surveillance studies. We selected TAC for use in the Aetiology of Neonatal Infection in South Asia (ANISA) study for identifying etiologies of severe disease in neonates in Bangladesh, India, and Pakistan. Here we report optimization of TAC to improve pathogen detection and overcome technical challenges associated with use of this technology in a large-scale surveillance study. Specifically, we increased the number of assay replicates, implemented a more robust RT-qPCR enzyme formulation, and adopted a more efficient method for extraction of total nucleic acid from blood specimens. We also report the development and analytical validation of ten new assays for use in the ANISA study. Based on these data, we revised the study-specific TACs for detection of 22 pathogens in NP/OP swabs and 12 pathogens in blood specimens as well as two control reactions (internal positive control and human nucleic acid control) for each specimen type. The cumulative improvements realized through these optimization studies will benefit ANISA and perhaps other studies utilizing multiple-pathogen detection approaches. These lessons may also contribute to the expansion of TAC technology to the clinical setting. PMID:23805203

Whole-leaf sanitizing wash improves chlorine efficacy for microbial reduction and prevents pathogen cross contamination during fresh-cut lettuce processing

USDA-ARS?s Scientific Manuscript database

Currently, nearly all fresh-cut lettuce processing facilities in the United States use chlorinated water or other sanitizer solutions for microbial reduction after lettuce is cut. It is believed that freshly cut lettuce releases significant amounts of organic matters that negatively impact the effec...

Bioleaching of heavy metals from sewage sludge: a review.

PubMed

Pathak, Ashish; Dastidar, M G; Sreekrishnan, T R

2009-06-01

During the treatment of sewage, a huge volume of sludge is generated, which is disposed of on land as soil fertilizer/conditioner due to the presence of nitrogen, phosphorus, potassium and other nutrients. However, the presence of toxic heavy metals and other toxic compounds in the sludge restricts its use as a fertilizer. Over the years, bioleaching has been developed as an environmentally friendly and cost-effective technology for the removal of heavy metals from the sludge. The present paper gives an overview of the various bioleaching studies carried out in different modes of operation. The various important aspects such as pathogen destruction, odor reduction and metal recovery from acidic leachate also have been discussed. Further, a detailed discussion was made on the various technical problems associated with the bioleaching process, which need to be addressed while developing the process on a larger scale.

Impact of exopolysaccharide production on functional properties of some Lactobacillus salivarius strains.

PubMed

Mercan, Emin; İspirli, Hümeyra; Sert, Durmuş; Yılmaz, Mustafa Tahsin; Dertli, Enes

2015-11-01

The aim of this work was to characterize functional properties of Lactobacillus salivarius strains isolated from chicken feces. Detection of genes responsible for exopolysaccharide (EPS) production revealed that all strains harbored a dextransucrase gene, but p-gtf gene was only detected in strain E4. Analysis of EPS production levels showed significant alterations among strains tested. Biofilm formation was found to be medium composition dependant, and there was a negative correlation with biofilm formation and EPS production. Autoaggregation properties and coaggregation of L. salivarius strains with chicken pathogens were appeared to be specific at strain level. An increment in bacterial adhesion to chicken gut explants was observed in L. salivarius strains with the reduction in EPS production levels. This study showed that strain-specific properties can determine the functional properties of L. salivarius strains, and the interference of these properties might be crucial for final selection of these strains for technological purposes.

Potential burden of antibiotic resistance on surgery and cancer chemotherapy antibiotic prophylaxis in the USA: a literature review and modelling study.

PubMed

Teillant, Aude; Gandra, Sumanth; Barter, Devra; Morgan, Daniel J; Laxminarayan, Ramanan

2015-12-01

The declining efficacy of existing antibiotics potentially jeopardises outcomes in patients undergoing medical procedures. We investigated the potential consequences of increases in antibiotic resistance on the ten most common surgical procedures and immunosuppressing cancer chemotherapies that rely on antibiotic prophylaxis in the USA. We searched the published scientific literature and identified meta-analyses and reviews of randomised controlled trials or quasi-randomised controlled trials (allocation done on the basis of a pseudo-random sequence-eg, odd/even hospital number or date of birth, alternation) to estimate the efficacy of antibiotic prophylaxis in preventing infections and infection-related deaths after surgical procedures and immunosuppressing cancer chemotherapy. We varied the identified effect sizes under different scenarios of reduction in the efficacy of antibiotic prophylaxis (10%, 30%, 70%, and 100% reductions) and estimated the additional number of infections and infection-related deaths per year in the USA for each scenario. We estimated the percentage of pathogens causing infections after these procedures that are resistant to standard prophylactic antibiotics in the USA. We estimate that between 38·7% and 50·9% of pathogens causing surgical site infections and 26·8% of pathogens causing infections after chemotherapy are resistant to standard prophylactic antibiotics in the USA. A 30% reduction in the efficacy of antibiotic prophylaxis for these procedures would result in 120,000 additional surgical site infections and infections after chemotherapy per year in the USA (ranging from 40,000 for a 10% reduction in efficacy to 280,000 for a 70% reduction in efficacy), and 6300 infection-related deaths (range: 2100 for a 10% reduction in efficacy, to 15,000 for a 70% reduction). We estimated that every year, 13,120 infections (42%) after prostate biopsy are attributable to resistance to fluoroquinolones in the USA. Increasing antibiotic resistance potentially threatens the safety and efficacy of surgical procedures and immunosuppressing chemotherapy. More data are needed to establish how antibiotic prophylaxis recommendations should be modified in the context of increasing rates of resistance. DRIVE-AB Consortium. Copyright © 2015 Elsevier Ltd. All rights reserved.

Quantification of Protozoa and Viruses from Small Water Volumes

PubMed Central

Bonilla, J. Alfredo; Bonilla, Tonya D.; Abdelzaher, Amir M.; Scott, Troy M.; Lukasik, Jerzy; Solo-Gabriele, Helena M.; Palmer, Carol J.

2015-01-01

Large sample volumes are traditionally required for the analysis of waterborne pathogens. The need for large volumes greatly limits the number of samples that can be processed. The goals of this study were to compare extraction and detection procedures for quantifying protozoan parasites and viruses from small volumes of marine water. The intent was to evaluate a logistically simpler method of sample collection and processing that would facilitate direct pathogen measures as part of routine monitoring programs. Samples were collected simultaneously using a bilayer device with protozoa capture by size (top filter) and viruses capture by charge (bottom filter). Protozoan detection technologies utilized for recovery of Cryptosporidium spp. and Giardia spp. were qPCR and the more traditional immunomagnetic separation—IFA-microscopy, while virus (poliovirus) detection was based upon qPCR versus plaque assay. Filters were eluted using reagents consistent with the downstream detection technologies. Results showed higher mean recoveries using traditional detection methods over qPCR for Cryptosporidium (91% vs. 45%) and poliovirus (67% vs. 55%) whereas for Giardia the qPCR-based methods were characterized by higher mean recoveries (41% vs. 28%). Overall mean recoveries are considered high for all detection technologies. Results suggest that simultaneous filtration may be suitable for isolating different classes of pathogens from small marine water volumes. More research is needed to evaluate the suitability of this method for detecting pathogens at low ambient concentration levels. PMID:26114244

Quantification of Protozoa and Viruses from Small Water Volumes.

PubMed

Bonilla, J Alfredo; Bonilla, Tonya D; Abdelzaher, Amir M; Scott, Troy M; Lukasik, Jerzy; Solo-Gabriele, Helena M; Palmer, Carol J

2015-06-24

Large sample volumes are traditionally required for the analysis of waterborne pathogens. The need for large volumes greatly limits the number of samples that can be processed. The aims of this study were to compare extraction and detection procedures for quantifying protozoan parasites and viruses from small volumes of marine water. The intent was to evaluate a logistically simpler method of sample collection and processing that would facilitate direct pathogen measures as part of routine monitoring programs. Samples were collected simultaneously using a bilayer device with protozoa capture by size (top filter) and viruses capture by charge (bottom filter). Protozoan detection technologies utilized for recovery of Cryptosporidium spp. and Giardia spp. were qPCR and the more traditional immunomagnetic separation-IFA-microscopy, while virus (poliovirus) detection was based upon qPCR versus plaque assay. Filters were eluted using reagents consistent with the downstream detection technologies. Results showed higher mean recoveries using traditional detection methods over qPCR for Cryptosporidium (91% vs. 45%) and poliovirus (67% vs. 55%) whereas for Giardia the qPCR-based methods were characterized by higher mean recoveries (41% vs. 28%). Overall mean recoveries are considered high for all detection technologies. Results suggest that simultaneous filtration may be suitable for isolating different classes of pathogens from small marine water volumes. More research is needed to evaluate the suitability of this method for detecting pathogens at low ambient concentration levels.

Adenovirus-based genetic vaccines for biodefense.

PubMed

Boyer, Julie L; Kobinger, Gary; Wilson, James M; Crystal, Ronald G

2005-02-01

The robust host responses elicited against transgenes encoded by (E1-)(E3-) adenovirus (Ad) gene transfer vectors can be used to develop Ad-based vectors as platform technologies for vaccines against potential bioterror pathogens. This review focuses on pathogens of major concern as bioterror agents and why Ad vectors are ideal as anti-bioterror vaccine platforms, providing examples from our laboratories of using Ad vectors as vaccines against potential bioterror pathogens and how Ad vectors can be developed to enhance vaccine efficacy in the bioterror war.

Recent advances in the use of laser-induced breakdown spectroscopy (LIBS) as a rapid point-of-care pathogen diagnostic

NASA Astrophysics Data System (ADS)

Rehse, Steven; Trojand, Daniel; Putnam, Russell; Gillies, Derek; Woodman, Ryan; Sheikh, Khadija; Daabous, Andrew

2013-05-01

There is a well-known and urgent need in the fields of medicine, environmental health and safety, food-processing, and defense/security to develop new 21st Century technologies for the rapid and sensitive identification of bacterial pathogens. In only the last five years, the use of a real-time elemental (atomic) analysis performed with laser-induced breakdown spectroscopy (LIBS) has made tremendous progress in becoming a viable technology for rapid bacterial pathogen detection and identification. In this talk we will show how this laser-based optical emission spectroscopic technique is able to sensitively assay the elemental composition of bacterial cells in situ. We will also present the latest achievements of our lab to fully develop LIBS-based bacterial sensing including simulation of a rapid urinary tract infection diagnosis and investigation of a variety of autonomous multivariate analysis algorithms. Lastly, we will show how this technology is now ready to be transitioned from the laboratory to field-portable and potentially man-portable instrumentation. The introduction of such a technology into popular use could very well transform the field of bacterial biosensing - a market valued at approximately 10 billion/year world-wide. Funding for this project was provided in part by a Natural Sciences and Engineering Research Council of Canada Discovery Grant.

Staphylococcus saprophyticus surface-associated protein (Ssp) is associated with lifespan reduction in Caenorhabditis elegans.

PubMed

Szabados, Florian; Mohner, Amelie; Kleine, Britta; Gatermann, Sören G

2013-10-01

Staphylococcal lipases have been proposed as pathogenicity factors. In Staphylococcus saprophyticus the surface-associated protein (Ssp) has been previously characterized as a cell wall-associated true lipase. A S. saprophyticus Δssp::ermB mutant has been described as less virulent in an in vivo model of urinary tract infection compared with its wild-type. This is the first report showing that S. saprophyticus induced a lifespan reduction in Caenorhabditis elegans similar to that of S. aureus RN4220. In two S. saprophyticus Δssp::ermB mutants lifespan reduction in C. elegans was partly abolished. In order to attribute virulence to the lipase activity itself and distinguish this phenomenon from the presence of the Ssp-protein, the conserved active site of the lipase was modified by site-directed ligase-independent mutagenesis and lipase activity-deficient mutants were constructed. These results indicate that the Ssp is associated with pathogenicity in C. elegans and one could speculate that the lipase activity itself is responsible for this virulence.

Staphylococcus saprophyticus surface-associated protein (Ssp) is associated with lifespan reduction in Caenorhabditis elegans

PubMed Central

Szabados, Florian; Mohner, Amelie; Kleine, Britta; Gatermann, Sören G

2013-01-01

Staphylococcal lipases have been proposed as pathogenicity factors. In Staphylococcus saprophyticus the surface-associated protein (Ssp) has been previously characterized as a cell wall-associated true lipase. A S. saprophyticus Δssp::ermB mutant has been described as less virulent in an in vivo model of urinary tract infection compared with its wild-type. This is the first report showing that S. saprophyticus induced a lifespan reduction in Caenorhabditis elegans similar to that of S. aureus RN4220. In two S. saprophyticus Δssp::ermB mutants lifespan reduction in C. elegans was partly abolished. In order to attribute virulence to the lipase activity itself and distinguish this phenomenon from the presence of the Ssp-protein, the conserved active site of the lipase was modified by site-directed ligase-independent mutagenesis and lipase activity-deficient mutants were constructed. These results indicate that the Ssp is associated with pathogenicity in C. elegans and one could speculate that the lipase activity itself is responsible for this virulence. PMID:23959029

A theoretical framework for biological control of soil-borne plant pathogens: Identifying effective strategies.

PubMed

Cunniffe, Nik J; Gilligan, Christopher A

2011-06-07

We develop and analyse a flexible compartmental model of the interaction between a plant host, a soil-borne pathogen and a microbial antagonist, for use in optimising biological control. By extracting invasion and persistence thresholds of host, pathogen and biological control agent, performing an equilibrium analysis, and numerical investigation of sensitivity to parameters and initial conditions, we determine criteria for successful biological control. We identify conditions for biological control (i) to prevent a pathogen entering a system, (ii) to eradicate a pathogen that is already present and, if that is not possible, (iii) to reduce the density of the pathogen. Control depends upon the epidemiology of the pathogen and how efficiently the antagonist can colonise particular habitats (i.e. healthy tissue, infected tissue and/or soil-borne inoculum). A sharp transition between totally effective control (i.e. eradication of the pathogen) and totally ineffective control can follow slight changes in biologically interpretable parameters or to the initial amounts of pathogen and biological control agent present. Effective biological control requires careful matching of antagonists to pathosystems. For preventative/eradicative control, antagonists must colonise susceptible hosts. However, for reduction in disease prevalence, the range of habitat is less important than the antagonist's bulking-up efficiency. Copyright © 2011 Elsevier Ltd. All rights reserved.

Evolution of pathogen virulence across space during an epidemic

USGS Publications Warehouse

Osnas, Erik; Hurtado, Paul J.; Dobson, Andrew P.

2015-01-01

We explore pathogen virulence evolution during the spatial expansion of an infectious disease epidemic in the presence of a novel host movement trade-off, using a simple, spatially explicit mathematical model. This work is motivated by empirical observations of the Mycoplasma gallisepticum invasion into North American house finch (Haemorhous mexicanus) populations; however, our results likely have important applications to other emerging infectious diseases in mobile hosts. We assume that infection reduces host movement and survival and that across pathogen strains the severity of these reductions increases with pathogen infectiousness. Assuming these trade-offs between pathogen virulence (host mortality), pathogen transmission, and host movement, we find that pathogen virulence levels near the epidemic front (that maximize wave speed) are lower than those that have a short-term growth rate advantage or that ultimately prevail (i.e., are evolutionarily stable) near the epicenter and where infection becomes endemic (i.e., that maximize the pathogen basic reproductive ratio). We predict that, under these trade-offs, less virulent pathogen strains will dominate the periphery of an epidemic and that more virulent strains will increase in frequency after invasion where disease is endemic. These results have important implications for observing and interpreting spatiotemporal epidemic data and may help explain transient virulence dynamics of emerging infectious diseases.

Flow cytometric analysis of microbial contamination in food industry technological lines--initial study.

PubMed

Józwa, Wojciech; Czaczyk, Katarzyna

2012-04-02

Flow cytometry constitutes an alternative for traditional methods of microorganisms identification and analysis, including methods requiring cultivation step. It enables the detection of pathogens and other microorganisms contaminants without the need to culture microbial cells meaning that the sample (water, waste or food e.g. milk, wine, beer) may be analysed directly. This leads to a significant reduction of time required for analysis allowing monitoring of production processes and immediate reaction in case of contamination or any disruption occurs. Apart from the analysis of raw materials or products on different stages of manufacturing process, the flow cytometry seems to constitute an ideal tool for the assessment of microbial contamination on the surface of technological lines. In the present work samples comprising smears from 3 different surfaces of technological lines from fruit and vegetable processing company from Greater Poland were analysed directly with flow cytometer. The measured parameters were forward and side scatter of laser light signals allowing the estimation of microbial cell contents in each sample. Flow cytometric analysis of the surface of food industry production lines enable the preliminary evaluation of microbial contamination within few minutes from the moment of sample arrival without the need of sample pretreatment. The presented method of fl ow cytometric initial evaluation of microbial state of food industry technological lines demonstrated its potential for developing a robust, routine method for the rapid and labor-saving detection of microbial contamination in food industry.

Genotype-by-sequencing of the plant-pathogenic fungi Pyrenophora teres and Sphaerulina musiva utilizing Ion Torrent sequence technology

USDA-ARS?s Scientific Manuscript database

The characterization of genes determining compatibility or incompatibility between plant pathogenic fungi and their hosts is important for the management of crop disease. The major focus of these interactions has typically been the identification and characterization of host genes, but it is equally...

Biotechnology: Genetically Engineered Pathogens (The Counterproliferation Papers, Future Warfare Series No. 53)

DTIC Science & Technology

2010-06-01

ENGINEERED PATHOGENS ....... 8 Binary biological weapons ...the crossroads of radicalism and technology. When the spread of chemical and biological and nuclear weapons , along with ballistic missile...and individuals, given the opportunity to employ biological weapons , will most likely use it to inflict harm and terror on the United States and its

Differentiation of live and dead salmonella cells using fourier transform infrared (FTIR) spectroscopy and principle component analysis (PCA) technique

USDA-ARS?s Scientific Manuscript database

Various technologies have been developed for pathogen detection using optical, electrochemical, biochemical and physical properties. Conventional microbiological methods need time from days to week to get the result. Though this method is very sensitive and accurate, a rapid detection of pathogens i...

ENVIRONMENTAL REGULATIONS AND TECHNOLOGY: CONTROL OF PATHOGENS AND VECTOR ATTRACTION IN SEWAGE SLUDGE (INCLUDING DOMESTIC SEWAGE) UNDER 40 CFR PART 503

EPA Science Inventory

This document describes the federal requirements concerning pathogens in sewage sludge applied to land or placed on a surface disposal site, and it provides guidance concerning those requirements. The document is intended for: (1) Owners and operators of treatment works treati...

Moving pathogen genomics out of the lab and into the clinic: what will it take?

PubMed

Luheshi, Leila M; Raza, Sobia; Peacock, Sharon J

2015-12-30

Pathogen genomic analysis is a potentially transformative new approach to the clinical and public-health management of infectious diseases. Health systems investing in this technology will need to build infrastructure and develop policies that ensure genomic information can be generated, shared and acted upon in a timely manner.

Assessing peracetic acid as a means to control post-vaccination Saprolegniasis in Atlantic salmon Salmo salar parr in recirculation aquaculture systems

USDA-ARS?s Scientific Manuscript database

Land-based closed containment facilities, utilizing recirculation aquaculture system (RAS) technologies, can reduce or eliminate the introduction of obligate fish pathogens. Regardless, the presence of opportunistic pathogens must be assumed, and these agents can cause disease during unfavorable con...

Complete genome of the cotton bacteria blight pathogen Xanthomonas citri pv. malvacearum strain MSCT

USDA-ARS?s Scientific Manuscript database

Xanthomonas citri pv. malvacearum (Xcm) is a major pathogen of Gossypium hirsutum. In this study we report the complete genome of the Xcm strain MSCT assembled from long read DNA sequencing technology. The MSCT genome is the first Xcm genome that has complete coding regions for Xcm transcriptional a...

Inactivation of foodborne pathogens in chicken purge or skin using a 405-nm LED array

USDA-ARS?s Scientific Manuscript database

Raw meat poultry are sometimes contaminated with foodborne pathogens, which can lead to illness in humans. In recent years research has focused on a variety of light technologies to decontaminate food and food contact surfaces during meat and poultry processing. In this study we evaluated the abilit...

Home Air Purifiers Eradicate Harmful Pathogens

NASA Technical Reports Server (NTRS)

2014-01-01

Marshall Space Flight Center funded the University of Madison-Wisconsin to develop ethylene scrubbers to keep produce fresh in space. Akida Holdings of Jacksonville, Florida, licensed the technology and developed Airocide, an air purifier that can kill airborne pathogens. Previously designed for industrial spaces, there is now a specially designed unit for home use.

Survival of fecal coliforms in dry-composting toilets.

PubMed

Redlinger, T; Graham, J; Corella-Barud, V; Avitia, R

2001-09-01

The dry-composting toilet, which uses neither water nor sewage infrastructure, is a practical solution in areas with inadequate sewage disposal and where water is limited. These systems are becoming increasingly popular and are promoted to sanitize human excreta and to recycle them into fertilizer for nonedible plants, yet there are few data on the safety of this technology. This study analyzed fecal coliform reduction in approximately 90 prefabricated, dry-composting toilets (Sistema Integral de Reciclamiento de Desechos Orgánicos [SIRDOs]) that were installed on the U.S.-Mexico border in Ciudad Juárez, Chihuahua, Mexico. The purpose of this study was to determine fecal coliform reduction over time and the most probable method of this reduction. Biosolid waste samples were collected and analyzed at approximately 3 and 6 months and were classified based on U.S. Environmental Protection Agency standards. Results showed that class A compost (high grade) was present in only 35.8% of SIRDOs after 6 months. The primary mechanism for fecal coliform reduction was found to be desiccation rather than biodegradation. There was a significant correlation (P = 0.008) between classification rating and percent moisture categories of the biosolid samples: drier samples had a greater proportion of class A samples. Solar exposure was critical for maximal class A biosolid end products (P = 0.001). This study only addressed fecal coliforms as an indicator organism, and further research is necessary to determine the safety of composting toilets with respect to other pathogenic microorganisms, some of which are more resistant to desiccation.

Effect of chlorine dioxide gas on Salmonella enterica inoculated on navel orange surfaces and its impact on the quality attributes of treated oranges.

PubMed

Bhagat, Arpan; Mahmoud, Barakat S M; Linton, Richard H

2011-01-01

Microorganisms, including pathogens of public health significance, have been shown to contaminate orange juice during the mechanical extraction of juice. The problem gets exacerbated when washed oranges have high initial microbial load, due to an insufficient postharvest treatment. The objective of this study was to investigate the reduction of Salmonella enterica on orange surfaces using ClO₂ gas treatments to achieve a 5 log reduction, consistent with the recommendations of the U.S. Department of Agriculture-National Advisory Committee on Microbiological Criteria for Foods. A mixed culture of four Salmonella strains, isolated from previous orange juice outbreaks, was spot inoculated onto orange skin surface areas. The oranges were then treated with 0.1, 0.3, and 0.5 mg/L ClO₂ gas for 2-14 minutes at 22°C and 90%-95% relative humidity. Surviving bacteria on treated areas were recovered and enumerated over treatment time on a nonselective medium, tryptic soy agar, followed by culturing onto a selective medium, xylose lysine deoxycholate agar. A >5 log reduction of Salmonella per sample of orange surface was observed with 0.1 and 0.3 mg/L ClO₂ gas treatments at 14 minutes and a similar log reduction was observed at 0.5 mg/L ClO₂ gas at 10 minutes. This result demonstrates that the treatment of oranges with ClO₂ gas is a promising technology that could be successfully employed for the treatment of whole oranges to reduce the risk of Salmonella outbreaks in orange juice.

Survival of Fecal Coliforms in Dry-Composting Toilets

PubMed Central

Redlinger, Thomas; Graham, Jay; Corella-Barud, Verónica; Avitia, Raquel

2001-01-01

The dry-composting toilet, which uses neither water nor sewage infrastructure, is a practical solution in areas with inadequate sewage disposal and where water is limited. These systems are becoming increasingly popular and are promoted to sanitize human excreta and to recycle them into fertilizer for nonedible plants, yet there are few data on the safety of this technology. This study analyzed fecal coliform reduction in approximately 90 prefabricated, dry-composting toilets (Sistema Integral de Reciclamiento de Desechos Orgánicos [SIRDOs]) that were installed on the U.S.-Mexico border in Ciudad Juárez, Chihuahua, Mexico. The purpose of this study was to determine fecal coliform reduction over time and the most probable method of this reduction. Biosolid waste samples were collected and analyzed at approximately 3 and 6 months and were classified based on U.S. Environmental Protection Agency standards. Results showed that class A compost (high grade) was present in only 35.8% of SIRDOs after 6 months. The primary mechanism for fecal coliform reduction was found to be desiccation rather than biodegradation. There was a significant correlation (P = 0.008) between classification rating and percent moisture categories of the biosolid samples: drier samples had a greater proportion of class A samples. Solar exposure was critical for maximal class A biosolid end products (P = 0.001). This study only addressed fecal coliforms as an indicator organism, and further research is necessary to determine the safety of composting toilets with respect to other pathogenic microorganisms, some of which are more resistant to desiccation. PMID:11526002

Pathogen reduction by ultraviolet C light effectively inactivates human white blood cells in platelet products.

PubMed

Pohler, Petra; Müller, Meike; Winkler, Carla; Schaudien, Dirk; Sewald, Katherina; Müller, Thomas H; Seltsam, Axel

2015-02-01

Residual white blood cells (WBCs) in cellular blood components induce a variety of adverse immune events, including nonhemolytic febrile transfusion reactions, alloimmunization to HLA antigens, and transfusion-associated graft-versus-host disease (TA-GVHD). Pathogen reduction (PR) methods such as the ultraviolet C (UVC) light-based THERAFLEX UV-Platelets system were developed to reduce the risk of transfusion-transmitted infection. As UVC light targets nucleic acids, it interferes with the replication of both pathogens and WBCs. This preclinical study aimed to evaluate the ability of UVC light to inactivate contaminating WBCs in platelet concentrates (PCs). The in vitro and in vivo function of WBCs from UVC-treated PCs was compared to that of WBCs from gamma-irradiated and untreated PCs by measuring cell viability, proliferation, cytokine secretion, antigen presentation in vitro, and xenogeneic GVHD responses in a humanized mouse model. UVC light was at least as effective as gamma irradiation in preventing GVHD in the mouse model. It was more effective in suppressing T-cell proliferation (>5-log reduction in the limiting dilution assay), cytokine secretion, and antigen presentation than gamma irradiation. The THERAFLEX UV-Platelets (MacoPharma) PR system can substitute gamma irradiation for TA-GVHD prophylaxis in platelet (PLT) transfusion. Moreover, UVC treatment achieves suppression of antigen presentation and inhibition of cytokine accumulation during storage of PCs, which has potential benefits for transfusion recipients. © 2014 AABB.

Nitrite addition to acidified sludge significantly improves digestibility, toxic metal removal, dewaterability and pathogen reduction

NASA Astrophysics Data System (ADS)

Du, Fangzhou; Keller, Jürg; Yuan, Zhiguo; Batstone, Damien J.; Freguia, Stefano; Pikaar, Ilje

2016-12-01

Sludge management is a major issue for water utilities globally. Poor digestibility and dewaterability are the main factors determining the cost for sludge management, whereas pathogen and toxic metal concentrations limit beneficial reuse. In this study, the effects of low level nitrite addition to acidified sludge to simultaneously enhance digestibility, toxic metal removal, dewaterability and pathogen reduction were investigated. Waste activated sludge (WAS) from a full-scale waste water treatment plant was treated at pH 2 with 10 mg NO2--N/L for 5 h. Biochemical methane potential tests showed an increase in the methane production of 28%, corresponding to an improvement from 247 ± 8 L CH4/kg VS to 317 ± 1 L CH4/kg VS. The enhanced removal of toxic metals further increased the methane production by another 18% to 360 ± 6 L CH4/kg VS (a total increase of 46%). The solids content of dewatered sludge increased from 14.6 ± 1.4% in the control to 18.2 ± 0.8%. A 4-log reduction for both total coliforms and E. coli was achieved. Overall, this study highlights the potential of acidification with low level nitrite addition as an effective and simple method achieving multiple improvements in terms of sludge management.

Nitrite addition to acidified sludge significantly improves digestibility, toxic metal removal, dewaterability and pathogen reduction

PubMed Central

Du, Fangzhou; Keller, Jürg; Yuan, Zhiguo; Batstone, Damien J.; Freguia, Stefano; Pikaar, Ilje

2016-01-01

Sludge management is a major issue for water utilities globally. Poor digestibility and dewaterability are the main factors determining the cost for sludge management, whereas pathogen and toxic metal concentrations limit beneficial reuse. In this study, the effects of low level nitrite addition to acidified sludge to simultaneously enhance digestibility, toxic metal removal, dewaterability and pathogen reduction were investigated. Waste activated sludge (WAS) from a full-scale waste water treatment plant was treated at pH 2 with 10 mg NO2−-N/L for 5 h. Biochemical methane potential tests showed an increase in the methane production of 28%, corresponding to an improvement from 247 ± 8 L CH4/kg VS to 317 ± 1 L CH4/kg VS. The enhanced removal of toxic metals further increased the methane production by another 18% to 360 ± 6 L CH4/kg VS (a total increase of 46%). The solids content of dewatered sludge increased from 14.6 ± 1.4% in the control to 18.2 ± 0.8%. A 4-log reduction for both total coliforms and E. coli was achieved. Overall, this study highlights the potential of acidification with low level nitrite addition as an effective and simple method achieving multiple improvements in terms of sludge management. PMID:28004811

[Application of isothermal amplification technology for pathogen detection in parasitic and other diseases].

PubMed

Ting, Li; Kun, Yang

2018-04-16

The in vitro nucleic acid amplification technique based on polymerase chain reaction (PCR) has been successfully applied to scientific researches. In recent years, the emergence of isothermal amplification technology is increasingly applied in the molecular diagnosis and disease detection because of its advantages of constant temperature, high efficiency, short time-consuming, and less reliance on equipment and instruments. The principle, characteristics and application of the partial isothermal amplification technique in the pathogen detection in parasitic and other diseases are reviewed in this paper, and the prospects of the wide development of the technique are also discussed.

Design and Construction of a Single-Tube, LATE-PCR, Multiplex Endpoint Assay with Lights-On/Lights-Off Probes for the Detection of Pathogens Associated with Sepsis

PubMed Central

Carver-Brown, Rachel K.; Reis, Arthur H.; Rice, Lisa M.; Czajka, John W.; Wangh, Lawrence J.

2012-01-01

Aims. The goal of this study was to construct a single tube molecular diagnostic multiplex assay for the detection of microbial pathogens commonly associated with septicemia, using LATE-PCR and Lights-On/Lights-Off probe technology. Methods and Results. The assay described here identified pathogens associated with sepsis by amplification and analysis of the 16S ribosomal DNA gene sequence for bacteria and specific gene sequences for fungi. A sequence from an unidentified gene in Lactococcus lactis subsp. cremoris served as a positive control for assay function. LATE-PCR was used to generate single-stranded amplicons that were then analyzed at endpoint over a wide temperature range in a specific fluorescent color. Each bacterial target was identified by its pattern of hybridization to Lights-On/Lights-Off probes derived from molecular beacons. Complex mixtures of targets were also detected. Conclusions. All microbial targets were identified in samples containing low starting copy numbers of pathogen genomic DNA, both as individual targets and in complex mixtures. Significance and Impact of the Study. This assay uses new technology to achieve an advance in the field of molecular diagnostics: a single-tube multiplex assay for identification of pathogens commonly associated with sepsis. PMID:23326668

Molecular assessment of bacterial pathogens - a contribution to drinking water safety.

PubMed

Brettar, Ingrid; Höfle, Manfred G

2008-06-01

Human bacterial pathogens are considered as an increasing threat to drinking water supplies worldwide because of the growing demand of high-quality drinking water and the decreasing quality and quantity of available raw water. Moreover, a negative impact of climate change on freshwater resources is expected. Recent advances in molecular detection technologies for bacterial pathogens in drinking water bear the promise in improving the safety of drinking water supplies by precise detection and identification of the pathogens. More importantly, the array of molecular approaches allows understanding details of infection routes of waterborne diseases, the effects of changes in drinking water treatment, and management of freshwater resources.

Bacteriophages as biocontrol agents of food pathogens.

PubMed

Mahony, Jennifer; McAuliffe, Olivia; Ross, R Paul; van Sinderen, Douwe

2011-04-01

Bacteriophages have long been recognized for their potential as biotherapeutic agents. The recent approval for the use of phages of Listeria monocytogenes for food safety purposes has increased the impetus of phage research to uncover phage-mediated applications with activity against other food pathogens. Areas of emerging and growing significance, such as predictive modelling and genomics, have shown their potential and impact on the development of new technologies to combat food pathogens. This review will highlight recent advances in the research of phages that target food pathogens and that promote their use in biosanitation, while it will also discuss its limitations. Copyright © 2010 Elsevier Ltd. All rights reserved.

Extreme Heat Resistance of Food Borne Pathogens Campylobacter jejuni, Escherichia coli, and Salmonella typhimurium on Chicken Breast Fillet during Cooking

PubMed Central

de Jong, Aarieke E. I.; van Asselt, Esther D.; Zwietering, Marcel H.; Nauta, Maarten J.; de Jonge, Rob

2012-01-01

The aim of this research was to determine the decimal reduction times of bacteria present on chicken fillet in boiling water. The experiments were conducted with Campylobacter jejuni, Salmonella, and Escherichia coli. Whole chicken breast fillets were inoculated with the pathogens, stored overnight (4°C), and subsequently cooked. The surface temperature reached 70°C within 30 sec and 85°C within one minute. Extremely high decimal reduction times of 1.90, 1.97, and 2.20 min were obtained for C. jejuni, E. coli, and S. typhimurium, respectively. Chicken meat and refrigerated storage before cooking enlarged the heat resistance of the food borne pathogens. Additionally, a high challenge temperature or fast heating rate contributed to the level of heat resistance. The data were used to assess the probability of illness (campylobacteriosis) due to consumption of chicken fillet as a function of cooking time. The data revealed that cooking time may be far more critical than previously assumed. PMID:22389647

Use of 1% peroxyacetic acid sanitizer in an air-mixing wash basin to remove bacterial pathogens from seeds.

PubMed

Rajkowski, Kathleen T; Ashurst, Kean

2009-11-01

To achieve the production of pathogen-free sprouts, there must be appropriate mixing of liquid sanitizer with the seeds to assure contact. Commercial treatments by irradiation or ozone gas of Salmonella spp. artificially inoculated seeds were compared, and these resulted in a 1 log reduction after all treatments. Use of peroxyacetic acid (1%) sanitizer on Salmonella spp. or Escherichia coli O157:H7 inoculated alfalfa seeds consistently resulted in a greater than 1 log reduction. In addition, during these studies debris was noted after the seeds were removed. Based on this observation, an air-mixing wash basin was developed for commercial use. Validation was done by commercial growers using 1% peroxyacetic acid sanitizer to wash seeds in the air-mixing basin, followed by sprouting the seeds. No positive or false-positive pathogen results were reported after the required testing of the sprout water (run-off during sprouting). Use of 1% peroxyacetic acid sanitizer in the air-mixing wash basin does provide the sprout grower an effective means of sanitizing sprout seeds.

Technologies and Concepts for Reducing the Fuel Burn of Subsonic Transport Aircraft

NASA Technical Reports Server (NTRS)

Nickol, Craig L.

2012-01-01

There are many technologies under development that have the potential to enable large fuel burn reductions in the 2025 timeframe for subsonic transport aircraft relative to the current fleet. This paper identifies a potential technology suite and analyzes the fuel burn reduction potential of these technologies when integrated into advanced subsonic transport concepts. Advanced tube-and-wing concepts are developed in the single aisle and large twin aisle class, and a hybrid-wing-body concept is developed for the large twin aisle class. The resulting fuel burn reductions for the advanced tube-and-wing concepts range from a 42% reduction relative to the 777-200 to a 44% reduction relative to the 737-800. In addition, the hybrid-wingbody design resulted in a 47% fuel burn reduction relative to the 777-200. Of course, to achieve these fuel burn reduction levels, a significant amount of technology and concept maturation is required between now and 2025. A methodology for capturing and tracking concept maturity is also developed and presented in this paper.

40 CFR 440.52 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2010 CFR

2010-07-01

... technology currently available (BPT). 440.52 Section 440.52 Protection of Environment ENVIRONMENTAL... reduction attainable by the application of the best practicable control technology currently available (BPT... effluent reduction attainable after application of the best practicable control technology currently...

40 CFR 440.52 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2011 CFR

2011-07-01

... technology currently available (BPT). 440.52 Section 440.52 Protection of Environment ENVIRONMENTAL... reduction attainable by the application of the best practicable control technology currently available (BPT... effluent reduction attainable after application of the best practicable control technology currently...

40 CFR 430.24 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2012 CFR

2012-07-01

... new technology components or process modifications and identifying critical path relationships within... degree of effluent reduction attainable by the application of best available technology economically... effluent reduction attainable by the application of best available technology economically achievable (BAT...

The clinical diagnostic accuracy of rapid detection of healthcare-associated bloodstream infection in intensive care using multipathogen real-time PCR technology

PubMed Central

Dunn, Graham; Chadwick, Paul; Young, Duncan; Bentley, Andrew; Carlson, Gordon; Warhurst, Geoffrey

2011-01-01

Background There is growing interest in the potential utility of real-time PCR in diagnosing bloodstream infection by detecting pathogen DNA in blood samples within a few hours. SeptiFast is a multipathogen probe-based real-time PCR system targeting ribosomal DNA sequences of bacteria and fungi. It detects and identifies the commonest pathogens causing bloodstream infection and has European regulatory approval. The SeptiFast pathogen panel is suited to identifying healthcare-associated bloodstream infection acquired during complex healthcare, and the authors report here the protocol for the first detailed health-technology assessment of multiplex real-time PCR in this setting. Methods/design A Phase III multicentre double-blinded diagnostic study will determine the clinical validity of SeptiFast for the rapid detection of healthcare-associated bloodstream infection, against the current service standard of microbiological culture, in an adequately sized population of critically ill adult patients. Results from SeptiFast and standard microbiological culture procedures in each patient will be compared at study conclusion and the metrics of clinical diagnostic accuracy of SeptiFast determined in this population setting. In addition, this study aims to assess further the preliminary evidence that the detection of pathogen DNA in the bloodstream using SeptiFast may have value in identifying the presence of infection elsewhere in the body. Furthermore, differences in circulating immune-inflammatory markers in patient groups differentiated by the presence/absence of culturable pathogens and pathogen DNA will help elucidate further the patho-physiology of infection developing in the critically ill. Ethics and dissemination Ethical approval has been granted by the North West 6 Research Ethics Committee (09/H1003/109). Based on the results of this first non-commercial study, independent recommendations will be made to The Department of Health (open-access health technology assessment report) as to whether SeptiFast has sufficient clinical diagnostic accuracy to move forward to efficacy testing during the provision of routine clinical care. PMID:22021785

Ceramic water filters impregnated with silver nanoparticles as a point-of-use water-treatment intervention for HIV-positive individuals in Limpopo Province, South Africa: a pilot study of technological performance and human health benefits.

PubMed

Abebe, Lydia Shawel; Smith, James A; Narkiewicz, Sophia; Oyanedel-Craver, Vinka; Conaway, Mark; Singo, Alukhethi; Amidou, Samie; Mojapelo, Paul; Brant, Julia; Dillingham, Rebecca

2014-06-01

Waterborne pathogens present a significant threat to people living with the human immunodeficiency virus (PLWH). This study presents a randomized, controlled trial that evaluates whether a household-level ceramic water filter (CWF) intervention can improve drinking water quality and decrease days of diarrhea in PLWH in rural South Africa. Seventy-four participants were randomized in an intervention group with CWFs and a control group without filters. Participants in the CWF arm received CWFs impregnated with silver nanoparticles and associated safe-storage containers. Water and stool samples were collected at baseline and 12 months. Diarrhea incidence was self-reported weekly for 12 months. The average diarrhea rate in the control group was 0.064 days/week compared to 0.015 days/week in the intervention group (p < 0.001, Mann-Whitney). Median reduction of total coliform bacteria was 100% at enrollment and final collection. CWFs are an acceptable technology that can significantly improve the quality of household water and decrease days of diarrhea for PLWH in rural South Africa.

Treatment of whole blood with riboflavin plus ultraviolet light, an alternative to gamma irradiation in the prevention of transfusion-associated graft-versus-host disease?

PubMed

Fast, Loren D; Nevola, Martha; Tavares, Jennifer; Reddy, Heather L; Goodrich, Ray P; Marschner, Susanne

2013-02-01

Exposure of blood products to gamma irradiation is currently the standard of care in the prevention of transfusion-associated graft-versus-host disease (TA-GVHD). Regulatory, technical, and clinical challenges associated with the use of gamma irradiators are driving efforts to develop alternatives. Pathogen reduction methods were initially developed to reduce the risk of microbial transmission by blood components. Through modifications of nucleic acids, these technologies interfere with the replication of both pathogens and white blood cells (WBCs). To date, systems for pathogen and WBC inactivation of products containing red blood cells are less well established than those for platelets and plasma. In this study, the in vitro and in vivo function of WBCs present in whole blood after exposure to riboflavin plus ultraviolet light (Rb-UV) was examined and compared to responses of WBCs obtained from untreated or gamma-irradiated blood by measuring proliferation, cytokine production, activation, and antigen presentation and xenogeneic (X-)GVHD responses in an in vivo mouse model. In vitro studies demonstrated that treatment of whole blood with Rb-UV was as effective as gamma irradiation in preventing WBC proliferation, but was more effective in preventing antigen presentation, cytokine production, and T-cell activation. Consistent with in vitro findings, treatment with Rb-UV was as effective as gamma irradiation in preventing X-GVHD, a mouse model for TA-GVHD. The ability to effectively inactivate WBCs in fresh whole blood using Rb-UV, prior to separation into components, provides the transfusion medicine community with a potential alternative to gamma irradiation. © 2012 American Association of Blood Banks.

Antagonistic effect of Pseudomonas graminis CPA-7 against foodborne pathogens in fresh-cut apples under simulated commercial conditions.

PubMed

Alegre, Isabel; Viñas, Inmaculada; Usall, Josep; Anguera, Marina; Altisent, Rosa; Abadias, Maribel

2013-04-01

Recently, we reported that the application of the strain CPA-7 of Pseudomonas graminis, previously isolated from apple, could reduce the population of foodborne pathogens on minimally processed (MP) apples and peaches under laboratory conditions. Therefore, the objective of the present work was to find an antioxidant treatment and a packaging atmosphere condition to improve CPA-7 efficacy in reducing a cocktail of four Salmonella and five Listeria monocytogenes strains on MP apples under simulated commercial processing. The effect of CPA-7 application on apple quality and its survival to simulated gastric stress were also evaluated. Ascorbic acid (2%, w/v) and N-acetyl-l-cysteine (1%, w/v) as antioxidant treatments reduced Salmonella, L. monocytogenes and CPA-7 recovery, meanwhile no reduction was observed with NatureSeal(®) AS1 (NS, 6%, w/v). The antagonistic strain was effective on NS-treated apple wedges stored at 10 °C with or without modified atmosphere packaging (MAP). Then, in a semi-commercial assay, efficacy of CPA-7 inoculated at 10(5) and 10(7) cfu mL(-1) against Salmonella and L. monocytogenes strains on MP apples with NS and MAP and stored at 5 and 10 °C was evaluated. Although high CPA-7 concentrations/populations avoided Salmonella growth at 10 °C and lowered L. monocytogenes population increases were observed at both temperatures, the effect was not instantaneous. No effect on apple quality was detected and CPA-7 did not survived to simulated gastric stress throughout storage. Therefore, CPA-7 could avoid pathogens growth on MP apples during storage when use as part of a hurdle technology in combination with disinfection techniques, low storage temperature and MAP. Copyright © 2012 Elsevier Ltd. All rights reserved.

40 CFR 415.432 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2010 CFR

2010-07-01

... technology currently available (BPT). 415.432 Section 415.432 Protection of Environment ENVIRONMENTAL... degree of effluent reduction attainable by the application of the best practicable control technology... effluent reduction attainable by the application of the best practicable control technology currently...

40 CFR 418.72 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2010 CFR

2010-07-01

... technology currently available. 418.72 Section 418.72 Protection of Environment ENVIRONMENTAL PROTECTION... degree of effluent reduction attainable by the application of the best practicable control technology... reduction attainable by the application of the best practicable control technology currently available (BPT...

40 CFR 415.272 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2010 CFR

2010-07-01

... technology currently available (BPT). 415.272 Section 415.272 Protection of Environment ENVIRONMENTAL... degree of effluent reduction attainable by the application of the best practicable control technology... effluent reduction attainable by the application of the best practicable control technology currently...

40 CFR 418.73 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2010 CFR

2010-07-01

... representing the degree of effluent reduction attainable by the application of the best available technology... effluent reduction attainable by the application of the best available technology economically achievable... subpart after application of the best available technology economically achievable: There shall be no...

40 CFR 415.292 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2010 CFR

2010-07-01

... technology currently available (BPT). 415.292 Section 415.292 Protection of Environment ENVIRONMENTAL... degree of effluent reduction attainable by the application of the best practicable control technology... effluent reduction attainable by the application of the best practicable control technology currently...

40 CFR 424.53 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2010 CFR

2010-07-01

... technology economically achievable: There shall be no discharge of process waste water pollutants to... representing the degree of effluent reduction attainable by the application of the best available technology... reduction attainable by the application of the best available technology economically achievable. The...

40 CFR 440.72 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2014 CFR

2014-07-01

... degree of effluent reduction attainable by the application of the best practicable control technology... attainable by the application of the best practicable control technology currently available (BPT). Except as... reduction attainable by the application of the best practicable control technology currently available (BPT...

40 CFR 440.12 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2014 CFR

2014-07-01

... degree of effluent reduction attainable by the application of the best practicable control technology... by the application of the best practicable control technology currently available (BPT). Except as... reduction attainable after application of the best practicable control technology currently available (BPT...

40 CFR 440.62 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2012 CFR

2012-07-01

... degree of effluent reduction attainable by the application of the best practicable control technology... attainable by the application of the best practicable control technology currently available (BPT). Except as... reduction attainable by the application of the best practicable control technology currently available (BPT...

40 CFR 440.12 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2013 CFR

2013-07-01

... degree of effluent reduction attainable by the application of the best practicable control technology... by the application of the best practicable control technology currently available (BPT). Except as... reduction attainable after application of the best practicable control technology currently available (BPT...

40 CFR 440.42 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2014 CFR

2014-07-01

... degree of effluent reduction attainable by the application of the best practicable control technology... attainable by the application of the best practicable control technology currently available (BPT). Except as... reduction attainable after application of the best practicable control technology currently available (BPT...

40 CFR 440.72 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2013 CFR

2013-07-01

... degree of effluent reduction attainable by the application of the best practicable control technology... attainable by the application of the best practicable control technology currently available (BPT). Except as... reduction attainable by the application of the best practicable control technology currently available (BPT...

40 CFR 440.42 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2012 CFR

2012-07-01

... degree of effluent reduction attainable by the application of the best practicable control technology... attainable by the application of the best practicable control technology currently available (BPT). Except as... reduction attainable after application of the best practicable control technology currently available (BPT...

40 CFR 434.53 - Effluent limitations guidelines representing the degree of effluent reduction attainable by...

Code of Federal Regulations, 2014 CFR

2014-07-01

... representing the degree of effluent reduction attainable by application of the best available technology... representing the degree of effluent reduction attainable by application of the best available technology... application of the best available technology economically achievable: BAT Effluent Limitations Pollutant or...

40 CFR 434.53 - Effluent limitations guidelines representing the degree of effluent reduction attainable by...

Code of Federal Regulations, 2012 CFR

2012-07-01

... representing the degree of effluent reduction attainable by application of the best available technology... representing the degree of effluent reduction attainable by application of the best available technology... application of the best available technology economically achievable: BAT Effluent Limitations Pollutant or...

40 CFR 440.62 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2014 CFR

2014-07-01

... degree of effluent reduction attainable by the application of the best practicable control technology... attainable by the application of the best practicable control technology currently available (BPT). Except as... reduction attainable by the application of the best practicable control technology currently available (BPT...

40 CFR 440.12 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2012 CFR

2012-07-01

... degree of effluent reduction attainable by the application of the best practicable control technology... by the application of the best practicable control technology currently available (BPT). Except as... reduction attainable after application of the best practicable control technology currently available (BPT...

40 CFR 440.113 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2014 CFR

2014-07-01

... degree of effluent reduction attainable by the application of the best available technology economically... attainable by the application of the best available technology economically achievable (BAT). Except as... reduction attainable by the application of the best available technology economically achievable (BAT): (a...

40 CFR 440.72 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2012 CFR

2012-07-01

... degree of effluent reduction attainable by the application of the best practicable control technology... attainable by the application of the best practicable control technology currently available (BPT). Except as... reduction attainable by the application of the best practicable control technology currently available (BPT...

40 CFR 434.53 - Effluent limitations guidelines representing the degree of effluent reduction attainable by...

Code of Federal Regulations, 2011 CFR

2011-07-01

... representing the degree of effluent reduction attainable by application of the best available technology... representing the degree of effluent reduction attainable by application of the best available technology... application of the best available technology economically achievable: BAT Effluent Limitations Pollutant or...

40 CFR 440.42 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2013 CFR

2013-07-01

... degree of effluent reduction attainable by the application of the best practicable control technology... attainable by the application of the best practicable control technology currently available (BPT). Except as... reduction attainable after application of the best practicable control technology currently available (BPT...

40 CFR 434.53 - Effluent limitations guidelines representing the degree of effluent reduction attainable by...

Code of Federal Regulations, 2010 CFR

2010-07-01

... representing the degree of effluent reduction attainable by application of the best available technology... representing the degree of effluent reduction attainable by application of the best available technology... application of the best available technology economically achievable: BAT Effluent Limitations Pollutant or...

40 CFR 440.62 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2013 CFR

2013-07-01

... degree of effluent reduction attainable by the application of the best practicable control technology... attainable by the application of the best practicable control technology currently available (BPT). Except as... reduction attainable by the application of the best practicable control technology currently available (BPT...

40 CFR 440.113 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2012 CFR

2012-07-01

... degree of effluent reduction attainable by the application of the best available technology economically... attainable by the application of the best available technology economically achievable (BAT). Except as... reduction attainable by the application of the best available technology economically achievable (BAT): (a...

40 CFR 430.114 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2012 CFR

2012-07-01

... degree of effluent reduction attainable by the application of the best available technology economically... representing the degree of effluent reduction attainable by the application of the best available technology... best available technology economically achievable (BAT). Non-continuous dischargers shall not be...

Understanding Class A and Pathogen Equivalency

EPA Science Inventory

Over the last several years, there has been a growing interest in using alternative technologies to produce Class A biosolids from municipal sludge. The 503 regulations include provisions for permitting the use of alternative and innovative treatment technologies. Under these pr...

INTRODUCING THE FIRST EVER PEC WEBSITE

EPA Science Inventory

Since it's creation in 1985, the Pathogen Equivalency Committee (PEC) has been reviewing novel sludge disinfection technologies and their ability to protect human health and the environment. The PEC is charged to make recommendations on whether these novel technologies provide eq...

Cold Plasma Technology-principles and applications

USDA-ARS?s Scientific Manuscript database

Contamination of fresh and fresh-cut fruits and vegetables by foodborne pathogens has prompted research into novel interventions. Cold plasma is a nonthermal food processing technology which uses energetic, reactive gases to inactivate contaminating microbes. This flexible sanitizing method uses ele...

Control of foodborne pathogens on fresh-cut fruit by a novel strain of Pseudomonas graminis.

PubMed

Alegre, Isabel; Viñas, Inmaculada; Usall, Josep; Teixidó, Neus; Figge, Marian J; Abadias, Maribel

2013-06-01

The consumption of fresh-cut fruit has substantially risen over the last few years, leading to an increase in the number of outbreaks associated with fruit. Moreover, consumers are currently demanding wholesome, fresh-like, safe foods without added chemicals. As a response, the aim of this study was to determine if the naturally occurring microorganisms on fruit are "competitive with" or "antagonistic to" potentially encountered pathogens. Of the 97 and 107 isolates tested by co-inoculation with Escherichia coli O157:H7, Salmonella and Listeria innocua on fresh-cut apple and peach, respectively, and stored at 20 °C, seven showed a strong antagonistic capacity (more than 1-log unit reduction). One of the isolates, CPA-7, achieved the best reduction values (from 2.8 to 5.9-log units) and was the only isolate able to inhibit E. coli O157:H7 at refrigeration temperatures on both fruits. Therefore, CPA-7 was selected for further assays. Dose-response assays showed that CPA-7 should be present in at least the same amount as the pathogen to adequately reduce the numbers of the pathogen. From the results obtained in in vitro assays, competition seemed to be CPA-7's mode of action against E. coli O157:H7. The CPA-7 strain was identified as Pseudomonas graminis. Thus, the results support the potential use of CPA-7 as a bioprotective agent against foodborne pathogens in minimally processed fruit. Copyright © 2013 Elsevier Ltd. All rights reserved.

Control of tick infestations and pathogen prevalence in cattle and sheep farms vaccinated with the recombinant Subolesin-Major Surface Protein 1a chimeric antigen

PubMed Central

2014-01-01

Background Despite the use of chemical acaricides, tick infestations continue to affect animal health and production worldwide. Tick vaccines have been proposed as a cost-effective and environmentally friendly alternative for tick control. Vaccination with the candidate tick protective antigen, Subolesin (SUB), has been shown experimentally to be effective in controlling vector infestations and pathogen infection. Furthermore, Escherichia coli membranes containing the chimeric antigen composed of SUB fused to Anaplasma marginale Major Surface Protein 1a (MSP1a) (SUB-MSP1a) were produced using a simple low-cost process and proved to be effective for the control of cattle tick, Rhipicephalus (Boophilus) microplus and R. annulatus infestations in pen trials. In this research, field trials were conducted to characterize the effect of vaccination with SUB-MSP1a on tick infestations and the prevalence of tick-borne pathogens in a randomized controlled prospective study. Methods Two cattle and two sheep farms with similar geographical locations and production characteristics were randomly assigned to control and vaccinated groups. Ticks were collected, counted, weighed and classified and the prevalence of tick-borne pathogens at the DNA and serological levels were followed for one year prior to and 9 months after vaccination. Results Both cattle and sheep developed antibodies against SUB in response to vaccination. The main effect of the vaccine in cattle was the 8-fold reduction in the percent of infested animals while vaccination in sheep reduced tick infestations by 63%. Female tick weight was 32-55% lower in ticks collected from both vaccinated cattle and sheep when compared to controls. The seroprevalence of Babesia bigemina was lower by 30% in vaccinated cattle, suggesting a possible role for the vaccine in decreasing the prevalence of this tick-borne pathogen. The effect of the vaccine in reducing the frequency of one A. marginale msp4 genotype probably reflected the reduction in the prevalence of a tick-transmitted strain as a result of the reduction in the percent of tick-infested cattle. Conclusions These data provide evidence of the dual effect of a SUB-based vaccine for controlling tick infestations and pathogen infection/transmission and provide additional support for the use of the SUB-MSP1a vaccine for tick control in cattle and sheep. PMID:24398155

Control of tick infestations and pathogen prevalence in cattle and sheep farms vaccinated with the recombinant Subolesin-Major Surface Protein 1a chimeric antigen.

PubMed

Torina, Alessandra; Moreno-Cid, Juan A; Blanda, Valeria; Fernández de Mera, Isabel G; de la Lastra, José M Pérez; Scimeca, Salvatore; Blanda, Marcellocalogero; Scariano, Maria Elena; Briganò, Salvatore; Disclafani, Rosaria; Piazza, Antonio; Vicente, Joaquín; Gortázar, Christian; Caracappa, Santo; Lelli, Rossella Colomba; de la Fuente, José

2014-01-08

Despite the use of chemical acaricides, tick infestations continue to affect animal health and production worldwide. Tick vaccines have been proposed as a cost-effective and environmentally friendly alternative for tick control. Vaccination with the candidate tick protective antigen, Subolesin (SUB), has been shown experimentally to be effective in controlling vector infestations and pathogen infection. Furthermore, Escherichia coli membranes containing the chimeric antigen composed of SUB fused to Anaplasma marginale Major Surface Protein 1a (MSP1a) (SUB-MSP1a) were produced using a simple low-cost process and proved to be effective for the control of cattle tick, Rhipicephalus (Boophilus) microplus and R. annulatus infestations in pen trials. In this research, field trials were conducted to characterize the effect of vaccination with SUB-MSP1a on tick infestations and the prevalence of tick-borne pathogens in a randomized controlled prospective study. Two cattle and two sheep farms with similar geographical locations and production characteristics were randomly assigned to control and vaccinated groups. Ticks were collected, counted, weighed and classified and the prevalence of tick-borne pathogens at the DNA and serological levels were followed for one year prior to and 9 months after vaccination. Both cattle and sheep developed antibodies against SUB in response to vaccination. The main effect of the vaccine in cattle was the 8-fold reduction in the percent of infested animals while vaccination in sheep reduced tick infestations by 63%. Female tick weight was 32-55% lower in ticks collected from both vaccinated cattle and sheep when compared to controls. The seroprevalence of Babesia bigemina was lower by 30% in vaccinated cattle, suggesting a possible role for the vaccine in decreasing the prevalence of this tick-borne pathogen. The effect of the vaccine in reducing the frequency of one A. marginale msp4 genotype probably reflected the reduction in the prevalence of a tick-transmitted strain as a result of the reduction in the percent of tick-infested cattle. These data provide evidence of the dual effect of a SUB-based vaccine for controlling tick infestations and pathogen infection/transmission and provide additional support for the use of the SUB-MSP1a vaccine for tick control in cattle and sheep.

Host-pathogen dynamics under sterilizing pathogens and fecundity-longevity trade-off in hosts.

PubMed

Janoušková, Eva; Berec, Luděk

2018-08-07

Infectious diseases are known to regulate population dynamics, an observation that underlies the use of pathogens as control agents of unwanted populations. Sterilizing rather than lethal pathogens are often suggested so as to avoid unnecessary suffering of the infected hosts. Until recently, models used to assess plausibility of pathogens as potential pest control agents have not included a possibility that reduced fecundity of the infected individuals may save their energy expenditure on reproduction and thus increase their longevity relative to the susceptible ones. Here, we develop a model of host-pathogen interaction that builds on this idea. We analyze the model for a variety of infection transmission functions, revealing that the indirect effect of sterilizing pathogens on mortality of the infected hosts, mediated by a fecundity-longevity trade-off, may cause hosts at endemic equilibria to attain densities higher than when there is no effect of pathogens on host mortality. On the other hand, an opposite outcome occurs when the fecundity-longevity trade-off is concave or when the degree of fecundity reduction by the pathogen is high enough. This points to a possibility that using sterilizing pathogens as agents of pest control may actually be less effective than previously thought, the more so since we also suggest that if sexual selection acts on the host species then the presence of sterilizing pathogens may even enhance host densities above the levels achieved without infection. Copyright © 2018 Elsevier Ltd. All rights reserved.

Five Reasons to Consider Phytophthora infestans a Reemerging Pathogen.

PubMed

Fry, W E; Birch, P R J; Judelson, H S; Grünwald, N J; Danies, G; Everts, K L; Gevens, A J; Gugino, B K; Johnson, D A; Johnson, S B; McGrath, M T; Myers, K L; Ristaino, J B; Roberts, P D; Secor, G; Smart, C D

2015-07-01

Phytophthora infestans has been a named pathogen for well over 150 years and yet it continues to "emerge", with thousands of articles published each year on it and the late blight disease that it causes. This review explores five attributes of this oomycete pathogen that maintain this constant attention. First, the historical tragedy associated with this disease (Irish potato famine) causes many people to be fascinated with the pathogen. Current technology now enables investigators to answer some questions of historical significance. Second, the devastation caused by the pathogen continues to appear in surprising new locations or with surprising new intensity. Third, populations of P. infestans worldwide are in flux, with changes that have major implications to disease management. Fourth, the genomics revolution has enabled investigators to make tremendous progress in terms of understanding the molecular biology (especially the pathogenicity) of P. infestans. Fifth, there remain many compelling unanswered questions.

Rapid Identification of Pathogens from Positive Blood Cultures by Multiplex PCR using the FilmArray System

PubMed Central

Blaschke, Anne J.; Heyrend, Caroline; Byington, Carrie L.; Fisher, Mark A.; Barker, Elizabeth; Garrone, Nicholas F.; Thatcher, Stephanie A.; Pavia, Andrew T.; Barney, Trenda; Alger, Garrison D.; Daly, Judy A.; Ririe, Kirk M.; Ota, Irene; Poritz, Mark A.

2012-01-01

Sepsis is a leading cause of death. Rapid and accurate identification of pathogens and antimicrobial resistance directly from blood culture could improve patient outcomes. The FilmArray® (FA; Idaho Technology, Inc., Salt Lake City, UT) Blood Culture (BC) panel can identify > 25 pathogens and 4 antibiotic resistance genes from positive blood cultures in 1 hour. We compared a development version of the panel to conventional culture and susceptibility testing on 102 archived blood cultures from adults and children with bacteremia. Of 109 pathogens identified by culture, 95% were identified by FA. Among 111 prospectively collected blood cultures, the FA identified 84 of 92 pathogens (91%) covered by the panel. Among 25 Staphylococcus aureus and 21 Enterococcus species detected, FA identified all culture-proven MRSA and VRE. The FA BC panel is an accurate method for the rapid identification of pathogens and resistance genes from blood culture. PMID:22999332

About the Drift Reduction Technology Program

EPA Pesticide Factsheets

The new voluntary Drift Reduction Technology (DRT) Program will encourage the manufacture, marketing, and use of safer spray technology and equipment scientifically verified to reduce pesticide drift.

Highly Bactericidal Macroporous Antimicrobial Polymeric Gel for Point-of-Use Water Disinfection.

PubMed

Kumar, Amit; Boyer, Cyrille; Nebhani, Leena; Wong, Edgar H H

2018-05-21

Access to clean and safe water supply remains inadequate in many developing countries. One of the key challenges is to remove pathogenic bacteria from the water supply via effective water disinfection technologies to prevent the spread of diseases and to ensure the safety of consumers. Herein, a highly effective point-of-use (on-demand) water disinfection technology, in the form of a polymeric scaffold called macroporous antimicrobial polymeric gel (MAPG), is demonstrated. MAPG is easy to fabricate, completely organic and possess inherent antimicrobial property which makes it non-reliant on inorganic compounds such as silver where the long-term toxicity remains unknown. MAPG is highly bactericidal and can disinfect bacteria-contaminated water (ca. 10 8  CFU mL -1 ) at a capacity of about >50 times the mass of the organic material used, inactivating >99% of both Gram-negative and Gram-positive bacteria including Escherichia coli, Vibrio cholerae and Staphylococcus aureus within 20 minutes of treatment. When fabricated in a syringe, MAPG eliminates E. coli from contaminated water source by >8.0 log 10 reduction in bacteria counts (i.e., no viable bacteria were detected after treatment), and the syringe can be reused multiple times without losing potency. The MAPG technology is not only restricted to water disinfection but may also be applicable in other bacteria inactivation applications.

Cold plasma decontamination of foods.

PubMed

Niemira, Brendan A

2012-01-01

Cold plasma is a novel nonthermal food processing technology that uses energetic, reactive gases to inactivate contaminating microbes on meats, poultry, fruits, and vegetables. This flexible sanitizing method uses electricity and a carrier gas, such as air, oxygen, nitrogen, or helium; antimicrobial chemical agents are not required. The primary modes of action are due to UV light and reactive chemical products of the cold plasma ionization process. A wide array of cold plasma systems that operate at atmospheric pressures or in low pressure treatment chambers are under development. Reductions of greater than 5 logs can be obtained for pathogens such as Salmonella, Escherichia coli O157:H7, Listeria monocytogenes, and Staphylococcus aureus. Effective treatment times can range from 120 s to as little as 3 s, depending on the food treated and the processing conditions. Key limitations for cold plasma are the relatively early state of technology development, the variety and complexity of the necessary equipment, and the largely unexplored impacts of cold plasma treatment on the sensory and nutritional qualities of treated foods. Also, the antimicrobial modes of action for various cold plasma systems vary depending on the type of cold plasma generated. Optimization and scale up to commercial treatment levels require a more complete understanding of these chemical processes. Nevertheless, this area of technology shows promise and is the subject of active research to enhance efficacy.

Application of FTA technology for sampling, recovery and molecular characterization of viral pathogens and virus-derived transgenes from plant tissues

PubMed Central

Ndunguru, Joseph; Taylor, Nigel J; Yadav, Jitender; Aly, Haytham; Legg, James P; Aveling, Terry; Thompson, Graham; Fauquet, Claude M

2005-01-01

Background Plant viral diseases present major constraints to crop production. Effective sampling of the viruses infecting plants is required to facilitate their molecular study and is essential for the development of crop protection and improvement programs. Retaining integrity of viral pathogens within sampled plant tissues is often a limiting factor in this process, most especially when sample sizes are large and when operating in developing counties and regions remote from laboratory facilities. FTA is a paper-based system designed to fix and store nucleic acids directly from fresh tissues pressed into the treated paper. We report here the use of FTA as an effective technology for sampling and retrieval of DNA and RNA viruses from plant tissues and their subsequent molecular analysis. Results DNA and RNA viruses were successfully recovered from leaf tissues of maize, cassava, tomato and tobacco pressed into FTA® Classic Cards. Viral nucleic acids eluted from FTA cards were found to be suitable for diagnostic molecular analysis by PCR-based techniques and restriction analysis, and for cloning and nucleotide sequencing in a manner equivalent to that offered by tradition isolation methods. Efficacy of the technology was demonstrated both from sampled greenhouse-grown plants and from leaf presses taken from crop plants growing in farmer's fields in East Africa. In addition, FTA technology was shown to be suitable for recovery of viral-derived transgene sequences integrated into the plant genome. Conclusion Results demonstrate that FTA is a practical, economical and sensitive method for sampling, storage and retrieval of viral pathogens and plant genomic sequences, when working under controlled conditions and in the field. Application of this technology has the potential to significantly increase ability to bring modern analytical techniques to bear on the viral pathogens infecting crop plants. PMID:15904535

New trends in emerging pathogens.

PubMed

Skovgaard, Niels

2007-12-15

The emergence of pathogens is the result of a number of impact in all parts of the food chain. The emerging technologies in food production explain how new pathogens can establish themselves in the food chain and compromise food safety. The impact of the food technology is analysed for several bacteria, such as Yersinia, Campylobacter, Arcobacter, Helicobacter pullorum, Enterobacter sakazakii, Mycobacterium avium spp. paratuberculosis, prions related to vCJD and others. The importance of the ability of many microbes to form VBNC forms is elaborated on. Research on culture independent methods may address this outstanding issue to the better understanding of emerging pathogens. The "demerging" of pathogens also occur, and examples of this are explained. The reaction of bacteria to stresses and sublethal treatments, and how exposure to one stress factor can confer resistance to other stresses, literally speaking causing contagious resistance, are explained. The implication of this e.g. in modern approaches of food preservation, such as Minimally processed Foods, is considerable. Intestinal colonization of EHEC may be regulated by Quorum sensing, and this ability of microbes plays an important role in the colonization of microbes in food and on food processing equipment, an important factor in the emergence of pathogens. The emergence of Saccharomyces cerevisiae, as an opportunistic human pathogen, used for centuries for food and production of alcoholic beverages, calls for research in molecular tools to distinguish between probiotic and clinical strains. Cyclospora cayetanensis and Norovirus outbreaks can no longer be designated as emerging pathogens, they share however one characteristic in the epidemiology of emerging nature, the importance of the hygiene in the primary production stage, including supply of potable water, and the application of GMP and the HACCP principles in the beginning of the food chain. Hepatitis E virus is a potential emerging food borne pathogen and swine may serve as a source of infection in human, a most challenging issue in greater part of the world raising pigs. Tick-borne encephalitis virus infection, either thick borne or caused by consumption of raw milk, is an increasing trend in the industrialized part of the world. Consumer awareness, ethics of food, sustainability in food production, and trust in foods, are of growing importance to the consumer. The reaction of the consumer to new technology, such as nanotechnology, is unpredictable. Many efforts should be devoted to communication of non-biased information to both the food producers as well as the consumer.

A noval approach to monitoring pathogen progression during uterine and placental infection in the mare using biophotonic imaging technology and lux modified bacteria

USDA-ARS?s Scientific Manuscript database

Uterine and placental infections are the leading cause of abortion, stillbirth, and preterm delivery in the mare. Whereas uterine and placental infections in women have been studied extensively, a comprehensive examination of the pathogenic processes leading to this unsatisfactory pregnancy outcome ...

Evaluation of 3M molecular detection system and ANSR pathogen detection system for rapid detection of salmonella from egg products

USDA-ARS?s Scientific Manuscript database

Loop-mediated isothermal amplification (LAMP) is a novel simple detection technology that amplifies DNA with high speed, efficiency, and specificity under isothermal conditions. The objective of this study was to evaluate the effectiveness of 3M Molecular Detection System (MDS) and ANSR Pathogen Det...

Propulsion Noise Reduction Research in the NASA Advanced Air Transport Technology Project

NASA Technical Reports Server (NTRS)

Van Zante, Dale; Nark, Douglas; Fernandez, Hamilton

2017-01-01

The Aircraft Noise Reduction (ANR) sub-project is focused on the generation, development, and testing of component noise reduction technologies progressing toward the NASA far term noise goals while providing associated near and mid-term benefits. The ANR sub-project has efforts in airframe noise reduction, propulsion (including fan and core) noise reduction, acoustic liner technology, and propulsion airframe aeroacoustics for candidate conventional and unconventional aircraft configurations. The current suite of propulsion specific noise research areas is reviewed along with emerging facility and measurement capabilities. In the longer term, the changes in engine and aircraft configuration will influence the suite of technologies necessary to reduce noise in next generation systems.

Celecoxib Enhances the Efficacy of Low-Dose Antibiotic Treatment against Polymicrobial Sepsis in Mice and Clinical Isolates of ESKAPE Pathogens

PubMed Central

Annamanedi, Madhavi; Varma, Gajapati Y. N.; Anuradha, K.; Kalle, Arunasree M.

2017-01-01

Treatment of multidrug resistant bacterial infections has been a great challenge globally. Previous studies including our study have highlighted the use of celecoxib, a non-steroidal anti-inflammatory drug in combination with antibiotic has decreased the minimal inhibitory concentration to limit Staphylococcus aureus infection. However, the efficacy of this combinatorial treatment against various pathogenic bacteria is not determined. Therefore, we have evaluated the potential use of celecoxib in combination with low doses of antibiotic in limiting Gram-positive and Gram-negative bacteria in vivo in murine polymicrobial sepsis developed by cecum ligation and puncture (CLP) method and against clinically isolated human ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species). The in vivo results clearly demonstrated a significant reduction in the bacterial load in different organs and in the inflammatory markers such as COX-2 and NF-κB via activation of SIRT1 in mice treated with imipenem, a choice of antibiotic for polymicrobial sepsis treatment. Combinatorial treatment of ampicillin and celecoxib was effective on clinical isolates of ESKAPE pathogens, 45% of tested clinical isolates showed more than 50% reduction in the colony forming units when compared to ampicillin alone. In conclusion, this non-traditional treatment strategy might be effective in clinic to reduce the dose of antibiotic to treat drug-resistant bacterial infections. PMID:28533769

Celecoxib Enhances the Efficacy of Low-Dose Antibiotic Treatment against Polymicrobial Sepsis in Mice and Clinical Isolates of ESKAPE Pathogens.

PubMed

Annamanedi, Madhavi; Varma, Gajapati Y N; Anuradha, K; Kalle, Arunasree M

2017-01-01

Treatment of multidrug resistant bacterial infections has been a great challenge globally. Previous studies including our study have highlighted the use of celecoxib, a non-steroidal anti-inflammatory drug in combination with antibiotic has decreased the minimal inhibitory concentration to limit Staphylococcus aureus infection. However, the efficacy of this combinatorial treatment against various pathogenic bacteria is not determined. Therefore, we have evaluated the potential use of celecoxib in combination with low doses of antibiotic in limiting Gram-positive and Gram-negative bacteria in vivo in murine polymicrobial sepsis developed by cecum ligation and puncture (CLP) method and against clinically isolated human ESKAPE pathogens ( Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa , and Enterobacter species). The in vivo results clearly demonstrated a significant reduction in the bacterial load in different organs and in the inflammatory markers such as COX-2 and NF-κB via activation of SIRT1 in mice treated with imipenem, a choice of antibiotic for polymicrobial sepsis treatment. Combinatorial treatment of ampicillin and celecoxib was effective on clinical isolates of ESKAPE pathogens, 45% of tested clinical isolates showed more than 50% reduction in the colony forming units when compared to ampicillin alone. In conclusion, this non-traditional treatment strategy might be effective in clinic to reduce the dose of antibiotic to treat drug-resistant bacterial infections.

Effect of atmospheric pressure plasma on inactivation of pathogens inoculated onto bacon using two different gas compositions.

PubMed

Kim, Binna; Yun, Hyejeong; Jung, Samooel; Jung, Yeonkook; Jung, Heesoo; Choe, Wonho; Jo, Cheorun

2011-02-01

Atmospheric pressure plasma (APP) is an emerging non-thermal pasteurization method for the enhancement of food safety. In this study, the effect of APP on the inactivation of pathogens inoculated onto bacon was observed. Sliced bacon was inoculated with Listeria monocytogenes (KCTC 3596), Escherichia coli (KCTC 1682), and Salmonella Typhimurium (KCTC 1925). The samples were treated with APP at 75, 100, and 125 W of input power for 60 and 90 s. Two gases, helium (10 lpm) or a mixture of helium and oxygen, (10 lpm and 10 sccm, respectively) were used for the plasma generation. Plasma with helium could only reduce the number of inoculated pathogens by about 1-2 Log cycles. On the other hand, the helium/oxygen gas mixture was able to achieve microbial reduction of about 2-3 Log cycles. The number of total aerobic bacteria showed 1.89 and 4.58 decimal reductions after plasma treatment with helium and the helium/oxygen mixture, respectively. Microscopic observation of the bacon after plasma treatment did not find any significant changes, except that the L∗-value of the bacon surface was increased. These results clearly indicate that APP treatment is effective for the inactivation of the three pathogens used in this study, although further investigation is needed for elucidating quality changes after treatment. Copyright © 2010 Elsevier Ltd. All rights reserved.

Shared and distinct mechanisms of iron acquisition by bacterial and fungal pathogens of humans

PubMed Central

Caza, Mélissa; Kronstad, James W.

2013-01-01

Iron is the most abundant transition metal in the human body and its bioavailability is stringently controlled. In particular, iron is tightly bound to host proteins such as transferrin to maintain homeostasis, to limit potential damage caused by iron toxicity under physiological conditions and to restrict access by pathogens. Therefore, iron acquisition during infection of a human host is a challenge that must be surmounted by every successful pathogenic microorganism. Iron is essential for bacterial and fungal physiological processes such as DNA replication, transcription, metabolism, and energy generation via respiration. Hence, pathogenic bacteria and fungi have developed sophisticated strategies to gain access to iron from host sources. Indeed, siderophore production and transport, iron acquisition from heme and host iron-containing proteins such as hemoglobin and transferrin, and reduction of ferric to ferrous iron with subsequent transport are all strategies found in bacterial and fungal pathogens of humans. This review focuses on a comparison of these strategies between bacterial and fungal pathogens in the context of virulence and the iron limitation that occurs in the human body as a mechanism of innate nutritional defense. PMID:24312900

Survival of Listeria monocytogenes on a conveyor belt material with or without antimicrobial additives.

PubMed

Chaitiemwong, N; Hazeleger, W C; Beumer, R R

2010-08-15

Survival of Listeria monocytogenes on a conveyor belt material with or without antimicrobial additives, in the absence or presence of food debris from meat, fish and vegetables and at temperatures of 10, 25 and 37 degrees C was investigated. The pathogen survived best at 10 degrees C, and better at 25 degrees C than at 37 degrees C on both conveyor belt materials. The reduction in the numbers of the pathogen on belt material with antimicrobial additives in the first 6h at 10 degrees C was 0.6 log unit, which was significantly higher (P<0.05) than the reduction of 0.2 log unit on belt material without additives. Reductions were significantly less (P<0.05) in the presence of food residue. At 37 degrees C and 20% relative humidity, large decreases in the numbers of the pathogen on both conveyor belt materials during the first 6h were observed. Under these conditions, there was no obvious effect of the antimicrobial substances. However, at 25 degrees C and 10 degrees C and high humidity (60-75% rh), a rapid decrease in bacterial numbers on the belt material with antimicrobial substances was observed. Apparently the reduction in numbers of L. monocytogenes on belt material with antimicrobial additives was greater than on belt material without additives only when the surfaces were wet. Moreover, the presence of food debris neutralized the effect of the antimicrobials. The results suggest that the antimicrobial additives in conveyor belt material could help to reduce numbers of microorganisms on belts at low temperatures when food residues are absent and belts are not rapidly dried. Copyright 2010 Elsevier B.V. All rights reserved.

40 CFR 430.112 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2014 CFR

2014-07-01

... degree of effluent reduction attainable by the application of the best practicable control technology... technology currently available (BPT). Except as provided in 40 CFR 125.30 through 125.32, any existing point... effluent reduction attainable by the application of the best practicable control technology currently...

40 CFR 430.112 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2012 CFR

2012-07-01

... degree of effluent reduction attainable by the application of the best practicable control technology... technology currently available (BPT). Except as provided in 40 CFR 125.30 through 125.32, any existing point... effluent reduction attainable by the application of the best practicable control technology currently...

40 CFR 430.112 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2013 CFR

2013-07-01

... degree of effluent reduction attainable by the application of the best practicable control technology... technology currently available (BPT). Except as provided in 40 CFR 125.30 through 125.32, any existing point... effluent reduction attainable by the application of the best practicable control technology currently...

Anthracnose of lucky bamboo Dracaena sanderiana caused by the fungus Colletotrichum dracaenophilum in Egypt.

PubMed

Morsy, Ahmed A; Elshahawy, Ibrahim E

2016-05-01

Dracaena sanderiana, of the family Liliaceae, is among the ornamental plants most frequently imported into Egypt. Typical anthracnose symptoms were observed on the stems of imported D. sanderiana samples. The pathogen was isolated, demonstrated to be pathogenic based on Koch's rule and identified as Colletotrichum dracaenophilum. The optimum temperature for its growth ranges from 25 to 30 °C, maintained for 8 days. Kemazed 50% wettable powder (WP) was the most effective fungicide against the pathogen, as no fungal growth was observed over 100 ppm. The biocontrol agents Trichoderma harzianum and Trichoderma viride followed by Bacillus subtilis and Bacillus pumilus caused the highest reduction in fungal growth. To the best of our knowledge, this report describes the first time that this pathogen was observed on D. sanderiana in Egypt.

Anthracnose of lucky bamboo Dracaena sanderiana caused by the fungus Colletotrichum dracaenophilum in Egypt

PubMed Central

Morsy, Ahmed A.; Elshahawy, Ibrahim E.

2016-01-01

Dracaena sanderiana, of the family Liliaceae, is among the ornamental plants most frequently imported into Egypt. Typical anthracnose symptoms were observed on the stems of imported D. sanderiana samples. The pathogen was isolated, demonstrated to be pathogenic based on Koch’s rule and identified as Colletotrichum dracaenophilum. The optimum temperature for its growth ranges from 25 to 30 °C, maintained for 8 days. Kemazed 50% wettable powder (WP) was the most effective fungicide against the pathogen, as no fungal growth was observed over 100 ppm. The biocontrol agents Trichoderma harzianum and Trichoderma viride followed by Bacillus subtilis and Bacillus pumilus caused the highest reduction in fungal growth. To the best of our knowledge, this report describes the first time that this pathogen was observed on D. sanderiana in Egypt. PMID:27222738

Cold Plasma as a nonthermal food processing technology

USDA-ARS?s Scientific Manuscript database

Contamination of fresh and fresh-cut fruits and vegetables by foodborne pathogens has prompted research into novel interventions. Cold plasma is a nonthermal food processing technology which uses energetic, reactive gases to inactivate contaminating microbes. This flexible sanitizing method uses ele...

Chapter 24. emerging technologies for irrigation water treatment

USDA-ARS?s Scientific Manuscript database

Several disinfestants that have potential for treating recycled irrigation water are less commonly used or newer developing technologies. Hydrogen peroxide can reduce spread of pathogens in water that contains nutrients or pesticide residues without generating toxic residues. Benefits potentially in...

Removal of human pathogenic viruses in a down-flow hanging sponge (DHS) reactor treating municipal wastewater and health risks associated with utilization of the effluent for agricultural irrigation.

PubMed

Kobayashi, Naohiro; Oshiki, Mamoru; Ito, Toshihiro; Segawa, Takahiro; Hatamoto, Masashi; Kato, Tsuyoshi; Yamaguchi, Takashi; Kubota, Kengo; Takahashi, Masanobu; Iguchi, Akinori; Tagawa, Tadashi; Okubo, Tsutomu; Uemura, Shigeki; Harada, Hideki; Motoyama, Toshiki; Araki, Nobuo; Sano, Daisuke

2017-03-01

A down-flow hanging sponge (DHS) reactor has been developed as a cost-effective wastewater treatment system that is adaptable to local conditions in low-income countries. A pilot-scale DHS reactor previously demonstrated stable reduction efficiencies for chemical oxygen demand (COD) and ammonium nitrogen over a year at ambient temperature, but the pathogen reduction efficiency of the DHS reactor has yet to be investigated. In the present study, the reduction efficiency of a pilot-scale DHS reactor fed with municipal wastewater was investigated for 10 types of human pathogenic viruses (norovirus GI, GII and GIV, aichivirus, astrovirus, enterovirus, hepatitis A and E viruses, rotavirus, and sapovirus). DHS influent and effluent were collected weekly or biweekly for 337 days, and concentrations of viral genomes were determined by microfluidic quantitative PCR. Aichivirus, norovirus GI and GII, enterovirus, and sapovirus were frequently detected in DHS influent, and the log 10 reduction (LR) of these viruses ranged from 1.5 to 3.7. The LR values for aichivirus and norovirus GII were also calculated using a Bayesian estimation model, and the average LR (±standard deviation) values for aichivirus and norovirus GII were estimated to be 1.4 (±1.5) and 1.8 (±2.5), respectively. Quantitative microbial risk assessment was conducted to calculate a threshold reduction level for norovirus GII that would be required for the use of DHS effluent for agricultural irrigation, and it was found that LRs of 2.6 and 3.7 for norovirus GII in the DHS effluent were required in order to not exceed the tolerable burden of disease at 10 -4 and 10 -6 disability-adjusted life years loss per person per year, respectively, for 95% of the exposed population during wastewater reuse for irrigation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Inactivation of Salmonella enterica and Listeria monocytogenes in cantaloupe puree by high hydrostatic pressure with/without added ascorbic acid.

PubMed

Mukhopadhyay, Sudarsan; Sokorai, Kimberly; Ukuku, Dike; Fan, Xuetong; Juneja, Vijay; Sites, Joseph; Cassidy, Jennifer

2016-10-17

The objective of this research was to evaluate and develop a method for inactivation of Salmonella enterica and Listeria monocytogenes in cantaloupe puree (CP) by high hydrostatic pressure (HHP). Cantaloupe being the most netted varieties of melons presents a greater risk of pathogen transmission. Freshly prepared CP with or without 0.1% ascorbic acid (AA) was inoculated with a bacterial cocktail composed of a three serotype mixture of S. enterica (S. Poona, S. Newport H1275 and S. Stanley H0558) and a mixture of three strains of L. monocytogenes (Scott A, 43256 and 51742) to a population of ca. 10(8)CFU/g. Double sealed and double bagged inoculated CP (ca. 5g) were pressure treated at 300, 400 and 500MPa at 8°C and 15°C for 5min. Data indicated increased inactivation of both Salmonella and Listeria spp. with higher pressure. Log reduction for CP at 300MPa, 8°C for 5min was 2.4±0.2 and 1.6±0.5logCFU/g for Salmonella and Listeria, respectively. Survivability of the pathogens was significantly compromised at 400MPa and 8°C, inactivating 4.5±0.3logCFU/g of Salmonella and 3.0±0.4logCFU/g of Listeria spp. Complete inactivation of the pathogens in the puree (log reduction >6.7logCFU/g), with or without AA, was achieved when the pressure was further increased to 500MPa, except that for Listeria containing no AA at 8°C. Listeria presented higher resistance to pressure treatment compared to Salmonella spp. Initial temperatures (8 and 15°C) had no significant influence on Salmonella log reductions. Log reduction of pathogens increased but not significantly with increase of temperature. AA did not show any significant antimicrobial activity. Viable counts were about 0.2-0.4logCFU/g less in presence of 0.1% AA. These data validate that HHP can be used as an effective method for decontamination of cantaloupe puree. Published by Elsevier B.V.

Efficacy of water treatment processes and endemic gastrointestinal illness - A multi-city study in Sweden.

PubMed

Tornevi, Andreas; Simonsson, Magnus; Forsberg, Bertil; Säve-Söderbergh, Melle; Toljander, Jonas

2016-10-01

Outbreaks of acute gastrointestinal illnesses (AGI) have been linked to insufficient drinking water treatment on numerous occasions in the industrialized world, but it is largely unknown to what extent public drinking water influences the endemic level of AGI. This paper aimed to examine endemic AGI and the relationship with pathogen elimination efficacy in public drinking water treatment processes. For this reason, time series data of all telephone calls to the Swedish National Healthcare Guide between November 2007 and February 2014 from twenty Swedish cities were obtained. Calls concerning vomiting, diarrhea or abdominal pain (AGI calls) were separated from other concerns (non-AGI calls). Information on which type of microbial barriers each drinking water treatment plant in these cities have been used were obtained, together with the barriers' theoretical pathogen log reduction efficacy. The total log reduction in the drinking water plants varied between 0.0 and 6.1 units for viruses, 0.0-14.6 units for bacteria and 0.0-7.3 units regarding protozoans. To achieve one general efficacy parameter for each plant, a weighted mean value of the log reductions (WLR) was calculated, with the weights based on how commonly these pathogen groups cause AGI. The WLR in the plants varied between 0.0 and 6.4 units. The effect of different pathogen elimination efficacy on levels of AGI calls relative non-AGI calls was evaluated in regression models, controlling for long term trends, population size, age distribution, and climatological area. Populations receiving drinking water produced with higher total log reduction was associated with a lower relative number of AGI calls. In overall, AGI calls decreased by 4% (OR = 0.96, CI: 0.96-0.97) for each unit increase in the WLR. The findings apply to both groundwater and surface water study sites, but are particularly evident among surface water sites during seasons when viruses are the main cause of AGI. This study proposes that the endemic level of gastroenteritis can indeed be reduced with more advanced treatment processes at many municipal drinking water treatment plants. Copyright © 2016 Elsevier Ltd. All rights reserved.

Reduction of Escherichia coli O157:H7 and Salmonella on laboratory-inoculated alfalfa seed with commercial citrus-related products.

PubMed

Fett, William F; Cooke, Peter H

2003-07-01

Alfalfa sprouts contaminated with the bacterial pathogens Escherichia coli O157:H7 and Salmonella have been the source of numerous outbreaks of foodborne illness in the United States and in other countries. The seed used for sprouting appears to be the primary source of these pathogens. The aim of this study was to determine whether the efficacy of commercial citrus-related products for sanitizing sprouting seed is similar to that of high levels of chlorine. Five products (Citrex, Pangermex, Citricidal, Citrobio, and Environné) were tested at concentrations of up to 20,000 ppm in sterile tap water and compared with buffered chlorine (at 16,000 ppm). Alfalfa seeds were inoculated with four-strain cocktails of Salmonella and E. coli O157:H7 to give final initial concentrations of ca. 9.0 and 7.0 CFU/g, respectively. Treatments (10 min) with Citrex, Pangermex, and Citricidal at 20,000 ppm and chlorine at 16,000 ppm produced similar log reductions for alfalfa seed inoculated with four-strain cocktails of E. coli O157:H7 and Salmonella (3.42 to 3.46 log CFU/g and 3.56 to 3.74 log CFU/g, respectively), and all four treatments were significantly (P<0.05) more effective than the control treatment (a buffer wash). Citrobio at 20,000 ppm was as effective as the other three products and chlorine against Salmonella but not against E. coli O157:H7. Environné was not more effective (producing reductions of 2.2 to 2.9 log CFU/g) than the control treatment (which produced reductions of 2.1 to 2.3 log CFU/g) against either pathogen. None of the treatments reduced seed germination. In vitro assays, as well as transmission electron microscopy, confirmed the antibacterial nature of the products that were effective against the two pathogens and indicated that they were bactericidal. When used at 20,000 ppm, the effective citrus-related products may be viable alternatives to chlorine for the sanitization of sprouting seed pending regulatory approval.

Waterborne Pathogens: The Protozoans.

PubMed

Moss, Joseph Anthony

2016-09-01

Waterborne diseases associated with polluted recreational and potable waters have been documented for more than a century. Key microbial protozoan parasites, such as Cryptosporidium and Giardia, are causative agents for gastrointestinal disease worldwide. Although not a first-line diagnostic approach for these diseases, medical imaging, such as radiography, computed tomography, magnetic resonance imaging, ultrasonography, and nuclear medicine technologies, can be used to evaluate patients with long-term effects. This article describes protozoan pathogens that affect human health, treatment of common waterborne pathogen-related diseases, and associated medical imaging. ©2016 American Society of Radiologic Technologists.

Viral pathogen discovery

PubMed Central

Chiu, Charles Y

2015-01-01

Viral pathogen discovery is of critical importance to clinical microbiology, infectious diseases, and public health. Genomic approaches for pathogen discovery, including consensus polymerase chain reaction (PCR), microarrays, and unbiased next-generation sequencing (NGS), have the capacity to comprehensively identify novel microbes present in clinical samples. Although numerous challenges remain to be addressed, including the bioinformatics analysis and interpretation of large datasets, these technologies have been successful in rapidly identifying emerging outbreak threats, screening vaccines and other biological products for microbial contamination, and discovering novel viruses associated with both acute and chronic illnesses. Downstream studies such as genome assembly, epidemiologic screening, and a culture system or animal model of infection are necessary to establish an association of a candidate pathogen with disease. PMID:23725672

Genomics of foodborne pathogens for microbial food safety.

PubMed

Allard, Marc W; Bell, Rebecca; Ferreira, Christina M; Gonzalez-Escalona, Narjol; Hoffmann, Maria; Muruvanda, Tim; Ottesen, Andrea; Ramachandran, Padmini; Reed, Elizabeth; Sharma, Shashi; Stevens, Eric; Timme, Ruth; Zheng, Jie; Brown, Eric W

2018-02-01

Whole genome sequencing (WGS) has been broadly used to provide detailed characterization of foodborne pathogens. These genomes for diverse species including Salmonella, Escherichia coli, Listeria, Campylobacter and Vibrio have provided great insight into the genetic make-up of these pathogens. Numerous government agencies, industry and academia have developed new applications in food safety using WGS approaches such as outbreak detection and characterization, source tracking, determining the root cause of a contamination event, profiling of virulence and pathogenicity attributes, antimicrobial resistance monitoring, quality assurance for microbiology testing, as well as many others. The future looks bright for additional applications that come with the new technologies and tools in genomics and metagenomics. Published by Elsevier Ltd.

Listeria: A foodborne pathogen that knows how to survive.

PubMed

Gandhi, Megha; Chikindas, Michael L

2007-01-01

The foodborne pathogen Listeria is the causative agent of listeriosis, a severe disease with high hospitalization and case fatality rates. Listeria monocytogenes can survive and grow over a wide range of environmental conditions such as refrigeration temperatures, low pH and high salt concentration. This allows the pathogen to overcome food preservation and safety barriers, and pose a potential risk to human health. This review focuses on the key issues such as survival of the pathogen in adverse environments, and the important adaptation and survival mechanisms such as biofilm formation, quorum sensing and antimicrobial resistance. Studies on the development of technologies to prevent and control L. monocytogenes contamination in foods and food processing facilities are also discussed.

Cold Plasma Inactivation of Bacterial Biofilms and Reduction of Quorum Sensing Regulated Virulence Factors

PubMed Central

Ziuzina, Dana; Boehm, Daniela; Patil, Sonal; Cullen, P. J.; Bourke, Paula

2015-01-01

The main objectives of this work were to investigate the effect of atmospheric cold plasma (ACP) against a range of microbial biofilms commonly implicated in foodborne and healthcare associated human infections and against P. aeruginosa quorum sensing (QS)-regulated virulence factors, such as pyocyanin, elastase (Las B) and biofilm formation capacity post-ACP treatment. The effect of processing factors, namely treatment time and mode of plasma exposure on antimicrobial activity of ACP were also examined. Antibiofilm activity was assessed for E. coli, L. monocytogenes and S. aureus in terms of reduction of culturability and retention of metabolic activity using colony count and XTT assays, respectively. All samples were treated ‘inpack’ using sealed polypropylene containers with a high voltage dielectric barrier discharge ACP generated at 80 kV for 0, 60, 120 and 300 s and a post treatment storage time of 24 h. According to colony counts, ACP treatment for 60 s reduced populations of E. coli to undetectable levels, whereas 300 s was necessary to significantly reduce populations of L. monocytogenes and S. aureus biofilms. The results obtained from XTT assay indicated possible induction of viable but non culturable state of bacteria. With respect to P. aeruginosa QS-related virulence factors, the production of pyocyanin was significantly inhibited after short treatment times, but reduction of elastase was notable only after 300 s and no reduction in actual biofilm formation was achieved post-ACP treatment. Importantly, reduction of virulence factors was associated with reduction of the cytotoxic effects of the bacterial supernatant on CHO-K1 cells, regardless of mode and duration of treatment. The results of this study point to ACP technology as an effective strategy for inactivation of established biofilms and may play an important role in attenuation of virulence of pathogenic bacteria. Further investigation is warranted to propose direct evidence for the inhibition of QS and mechanisms by which this may occur. PMID:26390435

Microbial antagonism as a potential solution for controlling selected root pathogens of crops

NASA Astrophysics Data System (ADS)

Cooper, Sarah; Agnew, Linda; Pereg, Lily

2016-04-01

Root pathogens of crops can cause large reduction in yield, however, there is a limited range of effective methods to control such pathogens. Soilborne pathogens that infect roots often need to survive in the rhizosphere, where there is high competition from other organisms. In such hot spots of microbial activity and growth, supported by root exudates, microbes have evolved antagonistic mechanisms that give them competitive advantages in winning the limited resources. Among these mechanisms is antibiosis, with production of some significant antifungal compounds including, antibiotics, volatile organic compounds, hydrogen cyanide and lytic enzymes. Some of these mechanisms may suppress disease through controlling the growth of root pathogens. In this project we isolated various fungi and bacteria that suppress the growth of cotton pathogens in vitro. The pathogen-suppressive microbes were isolated from cotton production soils that are under different management strategies, with and without the use of organic amendments. The potential of pathogen-suppressing microbes for controlling the black root rot disease, caused by the soilborne pathogen Thielaviopsis basicola, was confirmed using soil assays. We identified isolates with potential use as inoculant for cotton production in Australia. Having isolated a diverse group of antagonistic microbes enhances the probability that some would survive well in the soil and provide an alternative approach to address the problem of root disease affecting agricultural crops.

Use of the Blom Tracheotomy Tube with Suction Inner Cannula to Decontaminate Microorganisms from the Subglottic Space. A Proof of Concept.

PubMed

Rabach, Lesley; Siegel, Mark D; Puchalski, Jonathan T; Towle, Dana; Follert, Michelle; Johnson, Kelsey M; Rademaker, Alfred W; Leder, Steven B

2015-06-01

Preventing pulmonary complications during mechanical ventilation via tracheotomy is a high priority. To investigate if the Blom tracheotomy tube with suction-above-the-cuff inner cannula reduced the quantity of normal flora and pathogens in supra- versus subglottic spaces. We enrolled 20 consecutive medical ICU adults requiring tracheostomy for mechanical ventilation in this proof-of-concept, prospective, single-center study. All participants received a Blom tracheotomy tube with suction-above-the-cuff inner cannula to decontaminate microorganisms from the supra- and subglottic spaces. Supra- and subglottic sputum samples were obtained for microbiologic analysis while an endotracheal tube was in place before tracheotomy and once per week for up to 4 weeks of mechanical ventilation after tracheotomy. Demographics, duration of endotracheal tube intubation, and duration of mechanical ventilation post-tracheotomy were recorded. There was a significant reduction for supraglottic (2.86 ± 1.11 [mean ± SD]) versus subglottic suction samples (2.48 ± 1.07) (paired t test, P = 0.048; Wilcoxon test, P = 0.045) when all data pairs for normal flora and pathogens were combined across times. There was a significant reduction of normal flora pooled across times in 19 data pairs for supraglottic (3.00 ± 1.05) versus subglottic suction samples (2.00 ± 0.94) (paired t test, P = 0.0004; Wilcoxon test, P = 0.0007). There was no significant reduction of pathogens pooled across times in 25 data pairs for supraglottic (2.76 ± 1.16) versus subglottic suction samples (2.84 ± 1.03) (paired t test, P = 0.75; Wilcoxon test, P = 0.83). Proof-of-concept was confirmed. The Blom tracheotomy tube with disposable suction-above-the-cuff inner cannula decontaminated microorganisms from the subglottic space when normal flora and pathogens were combined. Future research should investigate if decreased quantity of normal flora and pathogens in the subglottic space reduces the incidence of ventilator-associated pulmonary complications in critically ill patients requiring ongoing mechanical ventilation via tracheotomy.

Reduction of Bacterial Pathogens and Potential Surrogates on the Surface of Almonds Using High-Intensity 405-Nanometer Light.

PubMed

Lacombe, Alison; Niemira, Brendan A; Sites, Joseph; Boyd, Glenn; Gurtler, Joshua B; Tyrell, Breanna; Fleck, Melissa

2016-11-01

The disinfecting properties of high-intensity monochromatic blue light (MBL) were investigated against Escherichia coli O157:H7, Salmonella , and nonpathogenic bacteria inoculated onto the surface of almonds. MBL was generated from an array of narrow-band 405-nm light-emitting diodes. Almonds were inoculated with higher or lower levels (8 or 5 CFU/g) of pathogenic E. coli O157:H7 and Salmonella , as well as nonpathogenic E. coli K-12 and an avirulent strain of Salmonella Typhimurium, for evaluation as potential surrogates for their respective pathogens. Inoculated almonds were treated with MBL for 0, 1, 2, 4, 6, 8, and 10 min at a working distance of 7 cm. Simultaneous to treatment, cooling air was directed onto the almonds at a rate of 4 ft 3 /min (1.89 ×10 -3 m 3 /s), sourced through a container of dry ice. An infrared camera was used to monitor the temperature readings after each run. For E. coli K-12, reductions of up to 1.85 or 1.63 log CFU/g were seen for higher and lower inoculum levels, respectively; reductions up to 2.44 and 1.44 log CFU/g were seen for E. coli O157:H7 (higher and lower inoculation levels, respectively). Attenuated Salmonella was reduced by up to 0.54 and 0.97 log CFU/g, whereas pathogenic Salmonella was reduced by up to 0.70 and 0.55 log CFU/g (higher and lower inoculation levels, respectively). Inoculation level did not significantly impact minimum effective treatment times, which ranged from 1 to 4 min. Temperatures remained below ambient throughout treatment, indicating that MBL is a nonthermal antimicrobial process. The nonpathogenic strains of E. coli and Salmonella each responded to MBL in a comparable manner to their pathogenic counterparts. These results suggest that these nonpathogenic strains may be useful in experiments with MBL in which a surrogate is required, and that MBL warrants further investigation as a potential antimicrobial treatment for low-moisture foods.

Simple model of epidemics with pathogen mutation.

PubMed

Girvan, Michelle; Callaway, Duncan S; Newman, M E J; Strogatz, Steven H

2002-03-01

We study how the interplay between the memory immune response and pathogen mutation affects epidemic dynamics in two related models. The first explicitly models pathogen mutation and individual memory immune responses, with contacted individuals becoming infected only if they are exposed to strains that are significantly different from other strains in their memory repertoire. The second model is a reduction of the first to a system of difference equations. In this case, individuals spend a fixed amount of time in a generalized immune class. In both models, we observe four fundamentally different types of behavior, depending on parameters: (1) pathogen extinction due to lack of contact between individuals; (2) endemic infection; (3) periodic epidemic outbreaks; and (4) one or more outbreaks followed by extinction of the epidemic due to extremely low minima in the oscillations. We analyze both models to determine the location of each transition. Our main result is that pathogens in highly connected populations must mutate rapidly in order to remain viable.

Swine and Poultry Pathogens: the Complete Genome Sequences of Two Strains of Mycoplasma hyopneumoniae and a Strain of Mycoplasma synoviae†

PubMed Central

Vasconcelos, Ana Tereza R.; Ferreira, Henrique B.; Bizarro, Cristiano V.; Bonatto, Sandro L.; Carvalho, Marcos O.; Pinto, Paulo M.; Almeida, Darcy F.; Almeida, Luiz G. P.; Almeida, Rosana; Alves-Filho, Leonardo; Assunção, Enedina N.; Azevedo, Vasco A. C.; Bogo, Maurício R.; Brigido, Marcelo M.; Brocchi, Marcelo; Burity, Helio A.; Camargo, Anamaria A.; Camargo, Sandro S.; Carepo, Marta S.; Carraro, Dirce M.; de Mattos Cascardo, Júlio C.; Castro, Luiza A.; Cavalcanti, Gisele; Chemale, Gustavo; Collevatti, Rosane G.; Cunha, Cristina W.; Dallagiovanna, Bruno; Dambrós, Bibiana P.; Dellagostin, Odir A.; Falcão, Clarissa; Fantinatti-Garboggini, Fabiana; Felipe, Maria S. S.; Fiorentin, Laurimar; Franco, Gloria R.; Freitas, Nara S. A.; Frías, Diego; Grangeiro, Thalles B.; Grisard, Edmundo C.; Guimarães, Claudia T.; Hungria, Mariangela; Jardim, Sílvia N.; Krieger, Marco A.; Laurino, Jomar P.; Lima, Lucymara F. A.; Lopes, Maryellen I.; Loreto, Élgion L. S.; Madeira, Humberto M. F.; Manfio, Gilson P.; Maranhão, Andrea Q.; Martinkovics, Christyanne T.; Medeiros, Sílvia R. B.; Moreira, Miguel A. M.; Neiva, Márcia; Ramalho-Neto, Cicero E.; Nicolás, Marisa F.; Oliveira, Sergio C.; Paixão, Roger F. C.; Pedrosa, Fábio O.; Pena, Sérgio D. J.; Pereira, Maristela; Pereira-Ferrari, Lilian; Piffer, Itamar; Pinto, Luciano S.; Potrich, Deise P.; Salim, Anna C. M.; Santos, Fabrício R.; Schmitt, Renata; Schneider, Maria P. C.; Schrank, Augusto; Schrank, Irene S.; Schuck, Adriana F.; Seuanez, Hector N.; Silva, Denise W.; Silva, Rosane; Silva, Sérgio C.; Soares, Célia M. A.; Souza, Kelly R. L.; Souza, Rangel C.; Staats, Charley C.; Steffens, Maria B. R.; Teixeira, Santuza M. R.; Urmenyi, Turan P.; Vainstein, Marilene H.; Zuccherato, Luciana W.; Simpson, Andrew J. G.; Zaha, Arnaldo

2005-01-01

This work reports the results of analyses of three complete mycoplasma genomes, a pathogenic (7448) and a nonpathogenic (J) strain of the swine pathogen Mycoplasma hyopneumoniae and a strain of the avian pathogen Mycoplasma synoviae; the genome sizes of the three strains were 920,079 bp, 897,405 bp, and 799,476 bp, respectively. These genomes were compared with other sequenced mycoplasma genomes reported in the literature to examine several aspects of mycoplasma evolution. Strain-specific regions, including integrative and conjugal elements, and genome rearrangements and alterations in adhesin sequences were observed in the M. hyopneumoniae strains, and all of these were potentially related to pathogenicity. Genomic comparisons revealed that reduction in genome size implied loss of redundant metabolic pathways, with maintenance of alternative routes in different species. Horizontal gene transfer was consistently observed between M. synoviae and Mycoplasma gallisepticum. Our analyses indicated a likely transfer event of hemagglutinin-coding DNA sequences from M. gallisepticum to M. synoviae. PMID:16077101

PhylloLux technology for crop protection: alternative management of diseases and arthropods for strawberry production

USDA-ARS?s Scientific Manuscript database

A search for alternatives to synthetic fungicides for control of strawberry diseases has led us to the development of PhylloLux© technology that combines UV-C irradiation followed by a specific dark period (2-4 hr depending on pathogen) and application of microbial antagonists. This technology is s...

Science & Technology Review January/February 2010

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bearinger, J P

2009-11-30

This month's issue has the following articles: (1) Innovative Materials Rise to the Radiation Challenge - Commentary by Bruce Warner; (2) The Hunt for Better Radiation Detection - New materials will help radiation detectors pick up weak signals and accurately identify illicit radioactive sources; (3) Time-Critical Technology Identifies Deadly Bloodborne Pathogens - A portable device can simultaneously distinguish up to five bloodborne pathogens in just minutes; (4) Defending Computer Networks against Attack - A Laboratory effort takes a new approach to detecting increasingly sophisticated cyber attacks; and (5) Imaging Cargo's Inner Secrets - Livermore-University of California collaborators are modeling amore » new radiographic technique for identifying nuclear materials concealed inside cargo containers.« less

Proteomic dissection of plant responses to various pathogens.

PubMed

Fang, Xianping; Chen, Jianping; Dai, Liangying; Ma, Huasheng; Zhang, Hengmu; Yang, Jian; Wang, Fang; Yan, Chengqi

2015-05-01

During their growth and development, plants are vulnerable to the effects of a variety of pathogens. Proteomics technology plays an important role in research studies of plant defense mechanisms by mining the expression changes of proteins in response to various biotic stresses. This review article provides a comprehensive overview of the latest developments in international proteomic research on plant biotic stress. It summarizes the methods commonly used in plant proteomic research to investigate biotic stress, analyze the protein responses of plants in adverse conditions, and reviews the applications of proteomics combined with transgenic technology in plant protection. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

How much reduction of virus is needed for recycled water: A continuous changing need for assessment?

PubMed

Gerba, Charles P; Betancourt, Walter Q; Kitajima, Masaaki

2017-01-01

To ensure the safety of wastewater reuse for irrigation of food crops and drinking water pathogenic viruses must be reduced to levels that pose no significant risk. To achieve this goal minimum reduction of viruses by treatment trains have been suggested. For use of edible crops a 6-log reduction and for production of potable drinking water a 12-log reduction has been suggested. These reductions were based on assuming infective virus concentrations of 10 5 to 10 6 per liter. Recent application of molecular methods suggests that some pathogenic viruses may be occurring in concentrations of 10 7 to 10 9 per liter. Factors influencing these levels include the development of molecular methods for virus detection, emergence of newly recognized viruses, decrease in per capita water use due to conservation measures, and outbreaks. Since neither cell culture nor molecular methods can assess all the potentially infectious virus in wastewater conservative estimates should be used to assess the virus load in untreated wastewater. This review indicates that an additional 2- to 3-log reduction of viruses above current recommendations may be needed to ensure the safety of recycled water. Information is needed on peak loading of viruses. In addition, more virus groups need to be quantified using better methods of virus quantification, including more accurate methods for measuring viral infectivity in order to better quantify risks from viruses in recycled water. Copyright © 2016 Elsevier Ltd. All rights reserved.

Application of ozonated dry ice (ALIGAL™ Blue Ice) for packaging and transport in the food industry.

PubMed

Fratamico, Pina M; Juneja, Vijay; Annous, Bassam A; Rasanayagam, Vasuhi; Sundar, M; Braithwaite, David; Fisher, Steven

2012-05-01

Dry ice is used by meat and poultry processors for temperature reduction during processing and for temperature maintenance during transportation. ALIGAL™ Blue Ice (ABI), which combines the antimicrobial effect of ozone (O(3)) along with the high cooling capacity of dry ice, was investigated for its effect on bacterial reduction in air, in liquid, and on food and glass surfaces. Through proprietary means, O(3) was introduced to produce dry ice pellets to a concentration of 20 parts per million (ppm) by total weight. The ABI sublimation rate was similar to that of dry ice pellets under identical conditions, and ABI was able to hold the O(3) concentration throughout the normal shelf life of the product. Challenge studies were performed using different microorganisms, including E. coli, Campylobacter jejuni, Salmonella, and Listeria, that are critical to food safety. ABI showed significant (P < 0.05) microbial reduction during bioaerosol contamination (up to 5-log reduction of E. coli and Listeria), on chicken breast (approximately 1.3-log reduction of C. jejuni), on contact surfaces (approximately 3.9 log reduction of C. jejuni), and in liquid (2-log reduction of C. jejuni). Considering the stability of O(3), ease of use, and antimicrobial efficacy against foodborne pathogens, our results suggest that ABI is a better alternative, especially for meat and poultry processors, as compared to dry ice. Further, ABI can potentially serve as an additional processing hurdle to guard against pathogens during processing, transportation, distribution, and/or storage. © 2012 Institute of Food Technologists®

ACTIVE PEC APPLICATIONS, THE PEC WEBSITE, AND SLUDGE STABILITY RESEARCH

EPA Science Inventory

Since it's creation in 1985, the Pathogen Equivalency Committee (PEC) has been reviewing novel sludge disinfection technologies with regards to their abilities to protect human health and the environment. The PEC is charged to make recommendations on whether these novel technolog...

ENVIRONMENTAL REGULATIONS AND TECHNOLOGY - AUTOTHERMAL THERMOPHILIC AEROBIC DIGESTION OF MUNICIPAL WASTEWATER SLUDGE

EPA Science Inventory

This document describes a promising technology — autothermal thermophilic aerobic digestion — for meeting the current and proposed U.S. federal requirements for pathogen controJ and land application of municipal wastewater sludge. Autothermal thermophilic aerobic digestion, or AT...

Rainfall and temperatures changes have confounding impacts on Phytophthora cinnamomi occurrence risk in the southwestern USA under climate change scenarios.

PubMed

Thompson, Sally E; Levin, Simon; Rodriguez-Iturbe, Ignacio

2014-04-01

Global change will simultaneously impact many aspects of climate, with the potential to exacerbate the risks posed by plant pathogens to agriculture and the natural environment; yet, most studies that explore climate impacts on plant pathogen ranges consider individual climatic factors separately. In this study, we adopt a stochastic modeling approach to address multiple pathways by which climate can constrain the range of the generalist plant pathogen Phytophthora cinnamomi (Pc): through changing winter soil temperatures affecting pathogen survival; spring soil temperatures and thus pathogen metabolic rates; and changing spring soil moisture conditions and thus pathogen growth rates through host root systems. We apply this model to the southwestern USA for contemporary and plausible future climate scenarios and evaluate the changes in the potential range of Pc. The results indicate that the plausible range of this pathogen in the southwestern USA extends over approximately 200,000 km(2) under contemporary conditions. While warming temperatures as projected by the IPCC A2 and B1 emissions scenarios greatly expand the range over which the pathogen can survive winter, projected reductions in spring rainfall reduce its feasible habitat, leading to spatially complex patterns of changing risk. The study demonstrates that temperature and rainfall changes associated with possible climate futures in the southwestern USA have confounding impacts on the range of Pc, suggesting that projections of future pathogen dynamics and ranges should account for multiple pathways of climate-pathogen interaction. © 2014 John Wiley & Sons Ltd.

Use of organic acids to inactivate Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes on organic fresh apples and lettuce.

PubMed

Park, Sang-Hyun; Choi, Mi-Ran; Park, Jeong-Woong; Park, Ki-Hwan; Chung, Myung-Sub; Ryu, Sangryeol; Kang, Dong-Hyun

2011-08-01

This study was undertaken to investigate the antimicrobial effect of organic acids against Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes on whole red organic apples and lettuce. Several studies have been conducted to evaluate organic acids as sanitizers. However, no studies have compared antimicrobial effects of various organic acids on organic fresh produce, including evaluation of color changes of produce. Apples and lettuce were inoculated with a cocktail of 3 strains each of 3 foodborne pathogens provided above and treated with 1% and 2% organic acids (propionic, acetic, lactic, malic, and citric acid) for 0, 0.5, 1, 5, and 10 min. With increasing treatment time and acid concentration, organic acid treatments showed significant reduction compared to the control treatment (distilled water), and differences in antimicrobial effects between organic acids were observed. After 10 min of treatment with 1% and 2% organic acids in apples, propionic (0.92 to 2.75 log reduction), acetic (0.52 to 2.78 log reduction), lactic (1.69 to >3.42 log reduction), malic (1.48 to >3.42 log reduction), and citric acid (1.52 to >3.42 log reduction) exhibited significant (P < 0.05) antibacterial effects against 3 foodborne pathogens compared to the control treatment. In lettuce, propionic (0.93 to 1.52 log reduction), acetic (1.13 to 1.74 log reduction), lactic (1.87 to 2.54 log reduction), malic (2.32 to 2.98 log reduction), and citric acid (1.85 to 2.86 log reduction) showed significant (P < 0.05) effects compared to the control treatment. Changes in sample color subjected to organic acids treatment were not significant during storage. It is suggested that organic acids have a potential as sanitizers for organic fresh produce. These data may help the organic produce industry provide safe fresh produce for consumers. © 2011 Institute of Food Technologists®

Hygienic effects and gas production of plastic bio-digesters under tropical conditions.

PubMed

Yen-Phi, Vo Thi; Clemens, Joachim; Rechenburg, Andrea; Vinneras, Björn; Lenssen, Christina; Kistemann, Thomas

2009-12-01

Plastic plug-flow bio-digesters have been promoted as a good option for improved treatment of manure and wastewater in developing countries although minimal information has been published on their hygienic status. This bench-scale study replicates bio-digester conditions to evaluate the reduction of pathogen and indicator microorganisms at three different hydraulic retention times (HRT) in the anaerobic treatment of pig manures at 30 degrees C for 50 days. Results showed that physicochemical values differed between HRTs. Gas production efficiency was better for longer HRTS. The accumulated sludge at the reactor's base increased with longer HRT. Phages and bacteria examined were reduced, but none was completely eliminated. Log10 reduction of bacteria ranged from 0.54 to 2.47. Phages ranged from 1.60 to 3.42. The reduction of organisms at HRT = 30 days was about one log10 unit higher than HRT = 15 days and about two log10 units higher than HRT = 3 days. The results indicate that the reduction of tested organisms increases with HRT. However the hygienic quality of the liquid effluent does not meet required quality values for surface and irrigation water. Longer HRTs are recommended to increase gas yield and achieve higher pathogen reduction. More barriers should be applied while handling bio-digester outputs to minimise risks to environmental and human health.

A potential disruptive technology in vaccine development: gene-based vaccines and their application to infectious diseases.

PubMed

Kaslow, David C

2004-10-01

Vaccine development requires an amalgamation of disparate disciplines and has unique economic and regulatory drivers. Non-viral gene-based delivery systems, such as formulated plasmid DNA, are new and potentially disruptive technologies capable of providing 'cheaper, simpler, and more convenient-to-use' vaccines. Typically and somewhat ironically, disruptive technologies have poorer product performance, at least in the near-term, compared with the existing conventional technologies. Because successful product development requires that the product's performance must meet or exceed the efficacy threshold for a desired application, the appropriate selection of the initial product applications for a disruptive technology is critical for its successful evolution. In this regard, the near-term successes of gene-based vaccines will likely be for protection against bacterial toxins and acute viral and bacterial infections. Recent breakthroughs, however, herald increasing rather than languishing performance improvements in the efficacy of gene-based vaccines. Whether gene-based vaccines ultimately succeed in eliciting protective immunity in humans to persistent intracellular pathogens, such as HIV, malaria and tuberculosis, for which the conventional vaccine technologies have failed, remains to be determined. A success against any one of the persistent intracellular pathogens would be sufficient proof that gene-based vaccines represent a disruptive technology against which future vaccine technologies will be measured.

Heightened sense for sensing: recent advances in pathogen immunoassay sensing platforms.

PubMed

Fischer, Nicholas O; Tarasow, Theodore M; Tok, Jeffrey B-H

2007-03-01

Rapid and efficient sensors are essential for effective defense against the emerging threat of bioterrorism and biological warfare. This review article describes several recent immunosensing advances that are relevant to biothreat detection. These highly diverse examples are intended to demonstrate the breadth of these immunochemical sensing systems and platforms while highlighting those technologies that are suitable for pathogen detection.

Charged Particles Kill Pathogens and Round Up Dust

NASA Technical Reports Server (NTRS)

2015-01-01

To keep plants fresh longer in space, Marshall Space Flight Center awarded funding to the University of Wisconsin-Madison to develop a titanium oxide-based device that reduced the amount of decay-inducing ethylene gas in the air. Electrolux (now Dallas-based Aerus Holdings) furthered the technology by developing an air purification product that kills pathogens both in the atmosphere and on surfaces.

A gaseous acetic acid treatment to disinfect fenugreek seeds and black pepper inoculated with pathogenic and spoilage bacteria.

PubMed

Nei, Daisuke; Enomoto, Katsuyoshi; Nakamura, Nobutaka

2015-08-01

Contamination of spices by pathogenic and/or spoilage bacteria can be deleterious to consumer's health and cause deterioration of foods, and inactivation of such bacteria is necessary for the food industry. The present study examined the effect of gaseous acetic acid treatment in reducing Escherichia coli O157:H7, Salmonella Enteritidis and Bacillus subtilis populations inoculated on fenugreek seeds and black pepper. Treatment with gaseous acetic acid at 0.3 mmol/L, 0.6 mmol/L and 4.7 mmol/L for 1-3 h significantly reduced the populations of E. coli O157:H7 and Salmonella Enteritidis on black pepper and fenugreek seeds at 55 °C (p < 0.05). The gas treatments at 4.7 mmol/L were more effective in inactivating the pathogens than the treatment at 0.3 mmol/L. An approximately 5.0 log reduction was obtained after 3 h of treatment with 4.7 mmol/L acetic acid. No significant reductions in the population of B. subtilis spores inoculated on fenugreek seeds and black pepper were obtained after the gas treatments at 0.3 mmol/L or 0.6 mmol/L (p > 0.05). However, the gas treatment at 4.7 mmol/L significantly reduced B. subtilis spores (p < 0.05), and 4.0 log CFU/g and 3.5 log CFU/g reductions on fenugreek seeds and black pepper, respectively, were obtained after 3 h of treatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effectiveness of Polyvalent Bacterial Lysate and Autovaccines Against Upper Respiratory Tract Bacterial Colonization by Potential Pathogens: A Randomized Study

PubMed Central

Zagólski, Olaf; Stręk, Paweł; Kasprowicz, Andrzej; Białecka, Anna

2015-01-01

Background Polyvalent bacterial lysate (PBL) is an oral immunostimulating vaccine consisting of bacterial standardized lysates obtained by lysis of different strains of bacteria. Autovaccines are individually prepared based on the results of smears obtained from the patient. Both types of vaccine can be used to treat an ongoing chronic infection. This study sought to determine which method is more effective against nasal colonization by potential respiratory tract pathogens. Material/Methods We enrolled 150 patients with aerobic Gram stain culture and count results indicating bacterial colonization of the nose and/or throat by potential pathogens. The participants were randomly assigned to each of the following groups: 1. administration of PBL, 2. administration of autovaccine, and 3. no intervention (controls). Results Reduction of the bacterial count in Streptococcus pneumoniae-colonized participants was significant after the autovaccine (p<0.001) and PBL (p<0.01). Reduction of the bacterial count of other β-hemolytic streptococcal strains after treatment with the autovaccine was significant (p<0.01) and was non-significant after PBL. In Haemophilus influenzae colonization, significant reduction in the bacterial count was noted in the PBL group (p<0.01). Methicillin-resistant Staphylococcus aureus colonization did not respond to either treatment. Conclusions The autovaccine is more effective than PBL for reducing bacterial count of Streptococcus pneumoniae and β-hemolytic streptococci, while PBL was more effective against Haemophilus influenzae colonization. PMID:26434686

Biocontrol of the wheat pathogen Zymoseptoria tritici using cyclic lipopeptides from Bacillus subtilis.

PubMed

Mejri, Samara; Siah, Ali; Coutte, François; Magnin-Robert, Maryline; Randoux, Béatrice; Tisserant, Benoit; Krier, François; Jacques, Philippe; Reignault, Philippe; Halama, Patrice

2017-06-21

Innovation toward ecofriendly plant protection products compatible with sustainable agriculture and healthy food is today strongly encouraged. Here, we assessed the biocontrol activity of three cyclic lipopeptides from Bacillus subtilis (mycosubtilin, M; surfactin, S; fengycin, F) and two mixtures (M + S and M + S + F) on wheat against Zymoseptoria tritici, the main pathogen on this crop. Foliar application of these biomolecules at a 100-mg L -1 concentration on the wheat cultivars Dinosor and Alixan, 2 days before fungal inoculation, provided significant reductions of disease severity. The best protection levels were recorded with the M-containing formulations (up to 82% disease reduction with M + S on Dinosor), while S and F treatments resulted in lower but significant disease reductions. In vitro and in planta investigations revealed that M-based formulations inhibit fungal growth, with half-maximal inhibitory concentrations of 1.4 mg L -1 for both M and M + S and 4.5 mg L -1 for M + S + F, thus revealing that the observed efficacy of these products may rely mainly on antifungal property. By contrast, S and F had no direct activity on the pathogen, hence suggesting that these lipopeptides act on wheat against Z. tritici as resistance inducers rather than as biofungicides. This study highlighted the efficacy of several lipopeptides from B. subtilis to biocontrol Z. tritici through likely distinct and biomolecule-dependent modes of action.

Integrated microfluidic system with automatic sampling for permanent molecular and antigen-based detection of CBRNE-related pathogens

NASA Astrophysics Data System (ADS)

Becker, Holger; Schattschneider, Sebastian; Klemm, Richard; Hlawatsch, Nadine; Gärtner, Claudia

2015-03-01

The continuous monitoring of the environment for lethal pathogens is a central task in the field of biothreat detection. Typical scenarios involve air-sampling in locations such as public transport systems or large public events and a subsequent analysis of the samples by a portable instrument. Lab-on-a-chip technologies are one of the promising technological candidates for such a system. We have developed an integrated microfluidic system with automatic sampling for the detection of CBRNE-related pathogens. The chip contains a two-pronged analysis strategy, on the one hand an immunological track using antibodies immobilized on a frit and a subsequent photometric detection, on the other hand a molecular biology approach using continuous-flow PCR with a fluorescence end-point detection. The cartridge contains two-component molded rotary valve to allow active fluid control and switching between channels. The accompanying instrument contains all elements for fluidic and valve actuation, thermal control, as well as the two detection modalities. Reagents are stored in dedicated reagent packs which are connected directly to the cartridge. With this system, we have been able to demonstrate the detection of a variety of pathogen species.

Space Age Spuds

NASA Technical Reports Server (NTRS)

2000-01-01

American Ag-Tech International, Ltd. developed a system called Quantum Tubers through the Wisconsin Center for Space Automation and Robotics (a NASA-sponsored Commercial Space Center). Using computerization and technologies originally intended for growing plants in space, the company developed a growth chamber that accelerates plant growth and is free of plant pathogens. The chamber is used to grow minitubers, which serve as nuclear seed stock for potatoes. Using lighting technology, temperature and humidity controls, and automation technology, the minituber can be generated in one closed facility with out much labor handling. This means they can be grown year round in extreme environments. The system eliminates the need for multiple generations of seed and eliminates exposure to pathogens, disease and pests. The Quantum Tubers system can produce 10-20 million tubers throughout the year, about equal to the world's supply of this generation seed stock.

Potassium permanganate cleansing is an effective sanitary method for the reduction of bacterial bioload on raw Coriandrum sativum.

PubMed

Subramanya, Supram Hosuru; Pai, Vasudha; Bairy, Indira; Nayak, Niranjan; Gokhale, Shishir; Sathian, Brijesh

2018-02-13

Raw vegetables including flowers, leaves, stems, and roots are important carriers of food borne pathogens. We evaluated the bacteriological contamination of unwashed coriander leaves, and effectiveness of cleansing with 0.1% potassium permanganate solution as decontamination method. Significant bacterial contamination including pathogens like Salmonella species and Aeromonas species were isolated from unwashed coriander leaves. Decontamination with 0.1% potassium permanganate was found to be more effective than three steps wash with sterile water.

40 CFR 408.292 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2014 CFR

2014-07-01

... representing the degree of effluent reduction attainable by the application of the best practicable control... degree of effluent reduction attainable by the application of the best practicable control technology... reduction attainable by the application of the best practicable control technology currently available (BPT...

40 CFR 408.292 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2012 CFR

2012-07-01

... representing the degree of effluent reduction attainable by the application of the best practicable control... degree of effluent reduction attainable by the application of the best practicable control technology... reduction attainable by the application of the best practicable control technology currently available (BPT...

40 CFR 408.292 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2010 CFR

2010-07-01

... representing the degree of effluent reduction attainable by the application of the best practicable control... degree of effluent reduction attainable by the application of the best practicable control technology... reduction attainable by the application of the best practicable control technology currently available (BPT...

40 CFR 408.292 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2013 CFR

2013-07-01

... representing the degree of effluent reduction attainable by the application of the best practicable control... degree of effluent reduction attainable by the application of the best practicable control technology... reduction attainable by the application of the best practicable control technology currently available (BPT...

40 CFR 408.292 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2011 CFR

2011-07-01

... representing the degree of effluent reduction attainable by the application of the best practicable control... degree of effluent reduction attainable by the application of the best practicable control technology... reduction attainable by the application of the best practicable control technology currently available (BPT...

Detection of ESKAPE Bacterial Pathogens at the Point of Care Using Isothermal DNA-Based Assays in a Portable Degas-Actuated Microfluidic Diagnostic Assay Platform

PubMed Central

Renner, Lars D.; Zan, Jindong; Hu, Linda I.; Martinez, Manuel; Resto, Pedro J.; Siegel, Adam C.; Torres, Clint; Hall, Sara B.; Slezak, Tom R.

2016-01-01

ABSTRACT An estimated 1.5 billion microbial infections occur globally each year and result in ∼4.6 million deaths. A technology gap associated with commercially available diagnostic tests in remote and underdeveloped regions prevents timely pathogen identification for effective antibiotic chemotherapies for infected patients. The result is a trial-and-error approach that is limited in effectiveness, increases risk for patients while contributing to antimicrobial drug resistance, and reduces the lifetime of antibiotics. This paper addresses this important diagnostic technology gap by describing a low-cost, portable, rapid, and easy-to-use microfluidic cartridge-based system for detecting the ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.) bacterial pathogens that are most commonly associated with antibiotic resistance. The point-of-care molecular diagnostic system consists of a vacuum-degassed microfluidic cartridge preloaded with lyophilized recombinase polymerase amplification (RPA) assays and a small portable battery-powered electronic incubator/reader. The isothermal RPA assays detect the targeted ESKAPE pathogens with high sensitivity (e.g., a limit of detection of ∼10 nucleic acid molecules) that is comparable to that of current PCR-based assays, and they offer advantages in power consumption, engineering, and robustness, which are three critical elements required for the point-of-care setting. IMPORTANCE This paper describes a portable system for rapidly identifying bacteria in resource-limited environments; we highlight the capabilities of the technology by detecting different pathogens within the ESKAPE collection, which cause nosocomial infections. The system is designed around isothermal DNA-based assays housed within an autonomous plastic cartridge that are designed with the end user in mind, who may have limited technological training. Displaying excellent sensitivity and specificity, the assay systems that we demonstrate may enable future diagnoses of bacterial infection to guide the development of effective chemotherapies and may have a role in areas beyond health where rapid detection is valuable, including in industrial processing and manufacturing, food security, agriculture, and water quality testing. PMID:27986722

Detection of ESKAPE Bacterial Pathogens at the Point of Care Using Isothermal DNA-Based Assays in a Portable Degas-Actuated Microfluidic Diagnostic Assay Platform.

PubMed

Renner, Lars D; Zan, Jindong; Hu, Linda I; Martinez, Manuel; Resto, Pedro J; Siegel, Adam C; Torres, Clint; Hall, Sara B; Slezak, Tom R; Nguyen, Tuan H; Weibel, Douglas B

2017-02-15

An estimated 1.5 billion microbial infections occur globally each year and result in ∼4.6 million deaths. A technology gap associated with commercially available diagnostic tests in remote and underdeveloped regions prevents timely pathogen identification for effective antibiotic chemotherapies for infected patients. The result is a trial-and-error approach that is limited in effectiveness, increases risk for patients while contributing to antimicrobial drug resistance, and reduces the lifetime of antibiotics. This paper addresses this important diagnostic technology gap by describing a low-cost, portable, rapid, and easy-to-use microfluidic cartridge-based system for detecting the ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.) bacterial pathogens that are most commonly associated with antibiotic resistance. The point-of-care molecular diagnostic system consists of a vacuum-degassed microfluidic cartridge preloaded with lyophilized recombinase polymerase amplification (RPA) assays and a small portable battery-powered electronic incubator/reader. The isothermal RPA assays detect the targeted ESKAPE pathogens with high sensitivity (e.g., a limit of detection of ∼10 nucleic acid molecules) that is comparable to that of current PCR-based assays, and they offer advantages in power consumption, engineering, and robustness, which are three critical elements required for the point-of-care setting. This paper describes a portable system for rapidly identifying bacteria in resource-limited environments; we highlight the capabilities of the technology by detecting different pathogens within the ESKAPE collection, which cause nosocomial infections. The system is designed around isothermal DNA-based assays housed within an autonomous plastic cartridge that are designed with the end user in mind, who may have limited technological training. Displaying excellent sensitivity and specificity, the assay systems that we demonstrate may enable future diagnoses of bacterial infection to guide the development of effective chemotherapies and may have a role in areas beyond health where rapid detection is valuable, including in industrial processing and manufacturing, food security, agriculture, and water quality testing. Copyright © 2017 Renner et al.

Nonthermal processing technologies as food safety intervention processes

USDA-ARS?s Scientific Manuscript database

Foods should provide sensorial satisfaction and nutrition to people. Yet, foodborne pathogens cause significant illness and lose of life to human kind every year. A processing intervention step may be necessary prior to the consumption to ensure the safety of foods. Nonthermal processing technologi...

Quantum changes in Helicobacter pylori gene expression accompany host-adaptation

PubMed Central

Wise, Michael J.; Khosravi, Yalda; Seow, Shih-Wee; Amoyo, Arlaine A.; Pettersson, Sven; Peters, Fanny; Tay, Chin-Yen; Perkins, Timothy T.; Loke, Mun-Fai; Marshall, Barry J.; Vadivelu, Jamuna

2017-01-01

Abstract Helicobacter pylori is a highly successful gastric pathogen. High genomic plasticity allows its adaptation to changing host environments. Complete genomes of H. pylori clinical isolate UM032 and its mice-adapted serial derivatives 298 and 299, generated using both PacBio RS and Illumina MiSeq sequencing technologies, were compared to identify novel elements responsible for host-adaptation. The acquisition of a jhp0562-like allele, which encodes for a galactosyltransferase, was identified in the mice-adapted strains. Our analysis implies a new β-1,4-galactosyltransferase role for this enzyme, essential for Ley antigen expression. Intragenomic recombination between babA and babB genes was also observed. Further, we expanded on the list of candidate genes whose expression patterns have been mediated by upstream homopolymer-length alterations to facilitate host adaption. Importantly, greater than four-fold reduction of mRNA levels was demonstrated in five genes. Among the down-regulated genes, three encode for outer membrane proteins, including BabA, BabB and HopD. As expected, a substantial reduction in BabA protein abundance was detected in mice-adapted strains 298 and 299 via Western analysis. Our results suggest that the expression of Ley antigen and reduced outer membrane protein expressions may facilitate H. pylori colonisation of mouse gastric epithelium. PMID:27803027

Contribution of high-content imaging technologies to the development of anti-infective drugs.

PubMed

Ang, Michelle Lay Teng; Pethe, Kevin

2016-08-01

Originally developed to study fundamental aspects of cellular biology, high-content imaging (HCI) was rapidly adapted to study host-pathogen interactions at the cellular level and adopted as a technology of choice to unravel disease biology. HCI platforms allow for the visualization and quantification of discrete phenotypes that cannot be captured using classical screening approaches. A key advantage of high-content screening technologies lies in the possibility to develop and interrogate physiologically significant, predictive ex vivo disease models that reproduce complex conditions relevant for infection. Here we review and discuss recent advances in HCI technologies and chemical biology approaches that are contributing to an increased understanding of the intricate host-pathogen interrelationship on the cellular level, and which will foster the development of novel therapeutic approaches for the treatment of human bacterial and protozoan infections. © 2016 The Authors. Cytometry Part A published by Wiley Periodicals, Inc. on behalf of ISAC. © 2016 The Authors. Cytometry Part A published by Wiley Periodicals, Inc. on behalf of ISAC.

A novel pathogenicity gene is required in the rice blast fungus to suppress the basal defenses of the host.

PubMed

Chi, Myoung-Hwan; Park, Sook-Young; Kim, Soonok; Lee, Yong-Hwan

2009-04-01

For successful colonization and further reproduction in host plants, pathogens need to overcome the innate defenses of the plant. We demonstrate that a novel pathogenicity gene, DES1, in Magnaporthe oryzae regulates counter-defenses against host basal resistance. The DES1 gene was identified by screening for pathogenicity-defective mutants in a T-DNA insertional mutant library. Bioinformatic analysis revealed that this gene encodes a serine-rich protein that has unknown biochemical properties, and its homologs are strictly conserved in filamentous Ascomycetes. Targeted gene deletion of DES1 had no apparent effect on developmental morphogenesis, including vegetative growth, conidial germination, appressorium formation, and appressorium-mediated penetration. Conidial size of the mutant became smaller than that of the wild type, but the mutant displayed no defects on cell wall integrity. The Deltades1 mutant was hypersensitive to exogenous oxidative stress and the activity and transcription level of extracellular enzymes including peroxidases and laccases were severely decreased in the mutant. In addition, ferrous ion leakage was observed in the Deltades1 mutant. In the interaction with a susceptible rice cultivar, rice cells inoculated with the Deltades1 mutant exhibited strong defense responses accompanied by brown granules in primary infected cells, the accumulation of reactive oxygen species (ROS), the generation of autofluorescent materials, and PR gene induction in neighboring tissues. The Deltades1 mutant displayed a significant reduction in infectious hyphal extension, which caused a decrease in pathogenicity. Notably, the suppression of ROS generation by treatment with diphenyleneiodonium (DPI), an inhibitor of NADPH oxidases, resulted in a significant reduction in the defense responses in plant tissues challenged with the Deltades1 mutant. Furthermore, the Deltades1 mutant recovered its normal infectious growth in DPI-treated plant tissues. These results suggest that DES1 functions as a novel pathogenicity gene that regulates the activity of fungal proteins, compromising ROS-mediated plant defense.

Liquid based formulations of bacteriophages for the management of waterborne bacterial pathogens in water microcosms.

PubMed

Ahiwale, Sangeeta; Tagunde, Sujata; Khopkar, Sushama; Karni, Mrudula; Gajbhiye, Milind; Kapadnis, Balasaheb

2013-11-01

Water resources are contaminated by life-threatening multidrug resistant pathogenic bacteria. Unfortunately, these pathogenic bacteria do not respond to the traditional water purification methods. Therefore, there is a need of environmentally friendly strategies to overcome the problems associated with the antimicrobial resistant bacterial pathogens. In the present study, highly potent lytic phages against multidrug-resistant Salmonella enterica serovar Paratyphi B, Pseudomonas aeruginosa and Klebsiella pneumoniae were isolated from the Pavana river water. They belonged to the Podoviridae and Siphoviridae families. These phages were purified and enriched in the laboratory. Monovalent formulations of phiSPB, BVPaP-3 and KPP phages were prepared in three different liquids viz., phage broth, saline and distilled water. The phages were stable for almost 8-10 months in the phage broth at 4 degrees C. The stability of the phages in saline and distilled water was 5-6 months at 4 degrees C. All of the phages were stable only for 4-6 months in the phage broth at 30 degrees C. The monovalent phage formulation of psiSPB was applied at MOI < 1, as disinfectant against an exponential and stationary phase cells of Salmonella enterica serovar Paratyphi B in various water microcosms. The results indicated that there was almost 80 % reduction in the log phase cells of Salmonella serovar Paratyphi B in 24 h. In stationary phase cells, the reduction was comparatively less within same period. At the same time, there was concomitant increase in the phage population by 80% in all the microcosms indicating that psiSPB phage is highly potent in killing pathogen in water. Results strongly support that the formulation of psiSPB in the phage broth in monovalent form could be used as an effective biological disinfectant for preventing transmission of water-borne bacterial pathogens, including antimicrobial resistant ones.

Efficiency of different air filter types for pig facilities at laboratory scale

PubMed Central

Wenke, Cindy; Pospiech, Janina; Reutter, Tobias; Truyen, Uwe

2017-01-01

Air filtration has been shown to be efficient in reducing pathogen burden in circulating air. We determined at laboratory scale the retention efficiency of different air filter types either composed of a prefilter (EU class G4) and a secondary fiberglass filter (EU class F9) or consisting of a filter mat (EU class M6 and F8-9). Four filter prototypes were tested for their capability to remove aerosol containing equine arteritis virus (EAV), porcine reproductive and respiratory syndrome virus (PRRSV), bovine enterovirus 1 (BEV), Actinobacillus pleuropneumoniae (APP), and Staphylococcus (S.) aureus from air. Depending on the filter prototype and utilisation, the airflow was set at 1,800 m3/h (combination of upstream prefilter and fiberglass filter) or 80 m3/h (filter mat). The pathogens were aerosolized and their concentration was determined in front of and behind the filter by culture or quantitative real-time RT-PCR. Furthermore, survival of the pathogens over time in the filter material was determined. Bacteria were most efficiently filtered with a reduction rate of up to 99.9% depending on the filter used. An approximately 98% reduction was achieved for the viruses tested. Viability or infectivity of APP or PRRSV in the filter material decreased below the detection limit after 4 h and 24 h, respectively, whereas S. aureus was still culturable after 4 weeks. Our results demonstrate that pathogens can efficiently be reduced by air filtration. Consequently, air filtration combined with other strict biosecurity measures markedly reduces the risk of introducing airborne transmitted pathogens to animal facilities. In addition, air filtration might be useful in reducing bioaerosols within a pig barn, hence improving respiratory health of pigs. PMID:29028843

Pseudomonas fluorescens CHA0 maintains carbon delivery to Fusarium graminearum-infected roots and prevents reduction in biomass of barley shoots through systemic interactions

PubMed Central

Henkes, Gunnar J.; Jousset, Alexandre; Bonkowski, Michael; Thorpe, Michael R.; Scheu, Stefan; Lanoue, Arnaud; Schurr, Ulrich; Röse, Ursula S. R.

2011-01-01

Soil bacteria such as pseudomonads may reduce pathogen pressure for plants, both by activating plant defence mechanisms and by inhibiting pathogens directly due to the production of antibiotics. These effects are hard to distinguish under field conditions, impairing estimations of their relative contributions to plant health. A split-root system was set up with barley to quantify systemic and local effects of pre-inoculation with Pseudomonas fluorescens on the subsequent infection process by the fungal pathogen Fusarium graminearum. One root half was inoculated with F. graminearum in combination with P. fluorescens strain CHA0 or its isogenic antibiotic-deficient mutant CHA19. Bacteria were inoculated either together with the fungal pathogen or in separate halves of the root system to separate local and systemic effects. The short-term plant response to fungal infection was followed by using the short-lived isotopic tracer 11CO2 to track the delivery of recent photoassimilates to each root half. In the absence of bacteria, fungal infection diverted carbon from the shoot to healthy roots, rather than to infected roots, although the overall partitioning from the shoot to the entire root system was not modified. Both local and systemic pre-inoculation with P. fluorescens CHA0 prevented the diversion of carbon as well as preventing a reduction in plant biomass in response to F. graminearum infection, whereas the non-antibiotic-producing mutant CHA19 lacked this ability. The results suggest that the activation of plant defences is a central feature of biocontrol bacteria which may even surpass the effects of direct pathogen inhibition. PMID:21561952

Efficiency of different air filter types for pig facilities at laboratory scale.

PubMed

Wenke, Cindy; Pospiech, Janina; Reutter, Tobias; Truyen, Uwe; Speck, Stephanie

2017-01-01

Air filtration has been shown to be efficient in reducing pathogen burden in circulating air. We determined at laboratory scale the retention efficiency of different air filter types either composed of a prefilter (EU class G4) and a secondary fiberglass filter (EU class F9) or consisting of a filter mat (EU class M6 and F8-9). Four filter prototypes were tested for their capability to remove aerosol containing equine arteritis virus (EAV), porcine reproductive and respiratory syndrome virus (PRRSV), bovine enterovirus 1 (BEV), Actinobacillus pleuropneumoniae (APP), and Staphylococcus (S.) aureus from air. Depending on the filter prototype and utilisation, the airflow was set at 1,800 m3/h (combination of upstream prefilter and fiberglass filter) or 80 m3/h (filter mat). The pathogens were aerosolized and their concentration was determined in front of and behind the filter by culture or quantitative real-time RT-PCR. Furthermore, survival of the pathogens over time in the filter material was determined. Bacteria were most efficiently filtered with a reduction rate of up to 99.9% depending on the filter used. An approximately 98% reduction was achieved for the viruses tested. Viability or infectivity of APP or PRRSV in the filter material decreased below the detection limit after 4 h and 24 h, respectively, whereas S. aureus was still culturable after 4 weeks. Our results demonstrate that pathogens can efficiently be reduced by air filtration. Consequently, air filtration combined with other strict biosecurity measures markedly reduces the risk of introducing airborne transmitted pathogens to animal facilities. In addition, air filtration might be useful in reducing bioaerosols within a pig barn, hence improving respiratory health of pigs.

Quantification of pathogen inactivation efficacy by free chlorine disinfection of drinking water for QMRA.

PubMed

Petterson, S R; Stenström, T A

2015-09-01

To support the implementation of quantitative microbial risk assessment (QMRA) for managing infectious risks associated with drinking water systems, a simple modeling approach for quantifying Log10 reduction across a free chlorine disinfection contactor was developed. The study was undertaken in three stages: firstly, review of the laboratory studies published in the literature; secondly, development of a conceptual approach to apply the laboratory studies to full-scale conditions; and finally implementation of the calculations for a hypothetical case study system. The developed model explicitly accounted for variability in residence time and pathogen specific chlorine sensitivity. Survival functions were constructed for a range of pathogens relying on the upper bound of the reported data transformed to a common metric. The application of the model within a hypothetical case study demonstrated the importance of accounting for variable residence time in QMRA. While the overall Log10 reduction may appear high, small parcels of water with short residence time can compromise the overall performance of the barrier. While theoretically simple, the approach presented is of great value for undertaking an initial assessment of a full-scale disinfection contactor based on limited site-specific information.

Kinetics of inactivation of indicator pathogens during thermophilic anaerobic digestion.

PubMed

Popat, Sudeep C; Yates, Marylynn V; Deshusses, Marc A

2010-12-01

Thermophilic anaerobic sludge digestion is a promising process to divert waste to beneficial use, but an important question is the required temperature and holding time to achieve a given degree of pathogen inactivation. In this study, the kinetics of inactivation of Ascaris suum and vaccine strain poliovirus type 1 (PVS-1), selected as indicators for helminth ova and enteric viruses respectively, were determined during anaerobic digestion at temperatures ranging from 51 to 56 °C. Inactivation of both indicator organisms was fast with greater than two log reductions achieved within 2 h for A. suum and three log reductions for PVS-1, suggesting that the current U.S. regulations are largely conservative. The first-order inactivation rate constants k followed Arrhenius relationship with activation energies of 105 and 39 KJ mol(-1) for A. suum and PVS-1, respectively indicating that A. suum was more sensitive to temperature. Although inactivation was fast, the presence of compounds in the sludge that are known to be protective of pathogen inactivation was observed, suggesting that composition-dependent time-temperature relationships are necessary. Copyright © 2010 Elsevier Ltd. All rights reserved.

Effects of combined treatments of irradiation and antimicrobial coatings on reduction of food pathogens in broccoli florets

NASA Astrophysics Data System (ADS)

Takala, P. N.; Salmieri, S.; Vu, K. D.; Lacroix, M.

2011-12-01

The effect of combined treatment of antimicrobial coatings and γ-radiation on reduction of food pathogens such as Listeria monocytogenes, Escherichia coli, and Salmonella Typhimurium was evaluated in broccoli florets. Broccoli florets were inoculated with pathogenic bacteria at 10 6 CFU/g. Inoculated florets were then coated with methylcellulose-based coating containing various mixtures of antimicrobial agents: organic acids (OAs) plus lactic acid bacteria metabolites (LABs), OA plus citrus extract (CE), OA plus CE plus spice mixture (SM), and OA plus rosemary extract (RE). Coated florets were irradiated with various doses (0-3.3 kGy), and microbial analyses were used to calculate the D10 value and radiosensitive relative. The coating containing OA plus CE was the most effective formulation for increasing the sensitization of Escherichia coli by 2.4 times as compared to the control without the antimicrobial coating. For Salmonella Typhimurium, coating containing OA plus LAB was the most effective formulation, increasing radiosensitivity by 2.4 times as well. All antimicrobial coatings had almost the same effect of increasing the sensitivity of Listeria monocytogenes (from 1.31 to 1.45 times) to γ-irradiation.

Highlights of PBTI Coimbra Conference on PRT of Plasma & Current Opinions on Pathogen Reduction Treatment of Blood Components.

PubMed

de Sousa, Gracinda; Seghatchian, Jerard

2015-04-01

Two experts from Octapharma and from Cerus addressed, in very concise ways, the concerns about non-viral inactivated FFP and how they managed to obtain highest standard of safety margin for pathogen reduction treatment [PRT] of plasma. The session was moderated by Portuguese Institute of Blood and Transplantation (PIBT) consultant advisor [Jerard Seghatchian] with long standing familiarity and international recognition in PR technologies for plasma, platelets and WB/red cells. The focus of conference was mainly on the criteria of acceptability of PRT-FFP; added values of having diversity in choice without fears of liability, as both of PRT technologies provide an excellent safeguard margins, for more than a decade of usage. In most European countries, it is believed that patients' safety come first followed by the safe usage initiatives, in particular using locally available products. Portugal is finally going forward with the implementation PRT plasma using its own FFP for their clinical use. The round table Q&A session focused on the impacts of the additional processing, which is still continuously improving, on the residual/emerging pathogen infectivity; eliminating the clinical impacts of donors viable leukocytes; the degree of altered product potency in particular cold activation of FVII; and loss of endothelial permeability factors during fluid storage of plasma. Both speakers highlighted their product safety and clinical efficacy using both routine in vitro, including the modern proteomic tests to establish the relevant changes in various parameters and in the overall clinical outcomes. The advancements in pharmacovigilance and hemovigilance, regulatory aspects and cost effectiveness were also highlighted. A local speaker [from the PIBT] described the state of the art of local processing issues and overall required standards used both during validation and the intercept process scale up, which is going ahead smoothly to providing the highest safety standards PRT-intercept plasma locally, in production now. Overall this was an excellent conference, open to transfusion medicine specialists and other health care professionals, for feedback and quality awareness, of providing diversity in choice, to local clinicians, who demand the best for the ultimate patient requirements. This is achieved in a period where both cost effectiveness and affordability matter, so is the clinical outcome, which ultimately counts. There was an atmosphere of non-competitive collaboration and sharing knowledge and working togetherness, even between two manufacturer representatives, which made the conference most joyful event. This was the opportunity to the scientific update and sharing "the once upon a time" impossible task of going for PRT-plasmas in Portugal, making it a reality in their local setting, in real time using Portuguese plasmas. This is in fact the timely news in the period of austerity, to provide a pre launching session for reporting the state of the arts of Portugal achievements to staff, academician, laboratory experts and clinician alike. Copyright © 2015 Elsevier Ltd. All rights reserved.

Definition of 1992 Technology Aircraft Noise Levels and the Methodology for Assessing Airplane Noise Impact of Component Noise Reduction Concepts

NASA Technical Reports Server (NTRS)

Kumasaka, Henry A.; Martinez, Michael M.; Weir, Donald S.

1996-01-01

This report describes the methodology for assessing the impact of component noise reduction on total airplane system noise. The methodology is intended to be applied to the results of individual study elements of the NASA-Advanced Subsonic Technology (AST) Noise Reduction Program, which will address the development of noise reduction concepts for specific components. Program progress will be assessed in terms of noise reduction achieved, relative to baseline levels representative of 1992 technology airplane/engine design and performance. In this report, the 1992 technology reference levels are defined for assessment models based on four airplane sizes - an average business jet and three commercial transports: a small twin, a medium sized twin, and a large quad. Study results indicate that component changes defined as program final goals for nacelle treatment and engine/airframe source noise reduction would achieve from 6-7 EPNdB reduction of total airplane noise at FAR 36 Stage 3 noise certification conditions for all of the airplane noise assessment models.

Study of CD69 antigen expression and integrity of leukocyte cellular membrane in stored platelet concentrates following irradiation and treatment with Mirasol® PRT System.

PubMed

Lachert, Elżbieta; Woźniak, Jolanta; Antoniewicz-Papis, Jolanta; Krzywdzińska, Agnieszka; Kubis, Jolanta; Mikołowska, Agata; Letowska, Magdalena

2017-01-01

Leukocytes in transfused blood components, particularly residual lymphocytes, have been shown to contribute to the occurrence of various adverse reactions. One of the most severe is transfusionassociated graft versus host disease (TA-GvHD) following transfusion of blood components contaminated with immunocompetent T lymphocytes. Irradiation is a routine method for protection against TA-GvHD. According to the literature, some pathogen reduction methods have also been proven effective for the inactivation of T lymphocytes, and so they may be considered as an alternative to irradiation. Comparison of CD69 antigen expression and the integrity of the leukocyte cellular membrane in stored platelet concentrates (PCs) following irradiation with the Gammacell 3000 Elan (Nordion Inc., Ottawa, Canada) and treatment with the Mirasol® Pathogen Reduction Technology (PRT) System (Terumo BCT, Lakewood, USA). The study included seven experiments. For each experiment we used 3 PCs, for Mirasol® PRT System treatment (M), for Gammacell 3000 Elan irradiation (R), and for the control (C). 7-amino-actinomycin D (7-AAD, Becton Dickinson, Franklin Lakes, USA) permeability was used to determine lymphocyte viability while CD69 antigen expression was the marker of lymphocyte activation. Analyses of 7-AAD and CD69 antigen expression were performed in a FACS Canto I flow cytometer (Becton Dickinson, USA). During 6 storage days, viable lymphocyte count decreased to 28% (p = 0.001) in the Mirasol® PRT System treated PCs and to 65% (p = 0.004) in the irradiated PCs. A statistically significant increase in CD69 expression in the irradiated PCs was observed; 1.3-fold on day 3 and 1.5-fold on day 6. In the Mirasol ® PRT System treated PCs, no statistically significant increase was observed. The in vitro results suggest that the Mirasol® PRT System is as effective as irradiation due to donor leukocyte inactivation capacity.

Primary hemostatic capacity of whole blood: a comprehensive analysis of pathogen reduction and refrigeration effects over time

PubMed Central

Pidcoke, Heather F.; McFaul, Steve J.; Ramasubramanian, Anand K.; Parida, Bijaya K.; Mora, Alex G.; Fedyk, Chriselda G.; Valdez-Delgado, Krystal K.; Montgomery, Robbie K.; Reddoch, Kristin M.; Rodriguez, Armando C.; Aden, James K.; Jones, John A.; Bryant, Ron S.; Scherer, Michael R.; Reddy, Heather L.; Goodrich, Raymond P.; Cap, Andrew P.

2014-01-01

BACKGROUND Whole blood (WB) has been used in combat since World War I as it is readily available and replaces every element of shed blood. Component therapy has become standard; however, recent military successes with WB resuscitation have revived the debate regarding wider WB use. Characterization of optimal WB storage is needed. We hypothesized that refrigeration preserves WB function and that a pathogen reduction technology (PRT) based on riboflavin and ultraviolet light has no deleterious effect over 21 days of storage. STUDY DESIGN AND METHODS WB units were stored for 21 days either at 4°C or 22°C. Half of each temperature group underwent PRT, yielding four final treatment groups (n = 8 each): CON 4 (WB at 4°C); CON 22 (WB at 22°C); PRT 4 (PRT WB at 4°C); and PRT 22 (PRT WB at 22°C). Testing was at baseline, Days 1–7, 10, 14, and 21. Assays included coagulation factors; platelet activation, aggregation, and adhesion; and thromboelastography (TEG). RESULTS Prothrombin time (PT) and partial thromboplastin time increased over time; refrigeration attenuated the effects on PT (p ≤ 0.009). Aggregation decreased over time (p ≤ 0.001); losses were attenuated by refrigeration (p ≤ 0.001). Refrigeration preserved TEG parameters (p ≤ 0.001) and PRT 4 samples remained within normal limits throughout the study. Refrigeration in combination with PRT inhibited fibrinolysis (p ≤ 0.001) and microparticle formation (p ≤ 0.031). Cold storage increased shear-induced platelet aggregation and ristocetin-induced platelet agglutination (p ≥ 0.032), as well as GPIb-expressing platelets (p ≤ 0.009). CONCLUSION The in vitro hemostatic function of WB is largely unaffected by PRT treatment and better preserved by cold storage over 21 days. Refrigerated PRT WB may be suitable for trauma resuscitation. Clinical studies are warranted. PMID:23301966

Biological control of postharvest pathogens

USDA-ARS?s Scientific Manuscript database

Postharvest diseases of harvested commodities cause significant reductions in food availability and financial profits. Additionally, regulatory agencies are increasingly restricting or banning the postharvest use of synthetic chemical fungicides. This has increased the need to develop more ecofrie...

Making a protein extract from plant pathogenic fungi for gel- and LC-based proteomics.

PubMed

Fernández, Raquel González; Redondo, Inmaculada; Jorrin-Novo, Jesus V

2014-01-01

Proteomic technologies have become a successful tool to provide relevant information on fungal biology. In the case of plant pathogenic fungi, this approach would allow a deeper knowledge of the interaction and the biological cycle of the pathogen, as well as the identification of pathogenicity and virulence factors. These two elements open up new possibilities for crop disease diagnosis and environment-friendly crop protection. Phytopathogenic fungi, due to its particular cellular characteristics, can be considered as a recalcitrant biological material, which makes it difficult to obtain quality protein samples for proteomic analysis. This chapter focuses on protein extraction for gel- and LC-based proteomics with specific protocols of our current research with Botrytis cinerea.

5-Nitroimidazole-derived Schiff bases and their copper(II) complexes exhibit potent antimicrobial activity against pathogenic anaerobic bacteria.

PubMed

Oliveira, Alexandre A; Oliveira, Ana P A; Franco, Lucas L; Ferencs, Micael O; Ferreira, João F G; Bachi, Sofia M P S; Speziali, Nivaldo L; Farias, Luiz M; Magalhães, Paula P; Beraldo, Heloisa

2018-05-07

In the present work a family of novel secnidazole-derived Schiff base compounds and their copper(II) complexes were synthesized. The antimicrobial activities of the compounds were evaluated against clinically important anaerobic bacterial strains. The compounds exhibited in vitro antibacterial activity against Bacteroides fragilis, Bacteroides thetaiotaomicron, Bacteroides vulgatus, Bacteroides ovatus, Parabacteroides distasonis and Fusubacterium nucleatum pathogenic anaerobic bacteria. Upon coordination to copper(II) the antibacterial activity significantly increased in several cases. Some derivatives were even more active than the antimicrobial drugs secnidazole and metronidazole. Therefore, the compounds under study are suitable for in vivo evaluation and the microorganisms should be classified as susceptible to them. Electrochemical studies on the reduction of the nitro group revealed that the compounds show comparable reduction potentials, which are in the same range of the bio-reducible drugs secnidazole and benznidazole. The nitro group reduction potential is more favorable for the copper(II) complexes than for the starting ligands. Hence, the antimicrobial activities of the compounds under study might in part be related to intracellular bio-reduction activation. Considering the increasing resistance rates of anaerobic bacteria against a wide range of antimicrobial drugs, the present work constitutes an important contribution to the development of new antibacterial drug candidates.

Pathogen dynamics during invasion and establishment of white-nose syndrome explain mechanisms of host persistence.

PubMed

Frick, Winifred F; Cheng, Tina L; Langwig, Kate E; Hoyt, Joseph R; Janicki, Amanda F; Parise, Katy L; Foster, Jeffrey T; Kilpatrick, A Marm

2017-03-01

Disease dynamics during pathogen invasion and establishment determine the impacts of disease on host populations and determine the mechanisms of host persistence. Temporal progression of prevalence and infection intensity illustrate whether tolerance, resistance, reduced transmission, or demographic compensation allow initially declining populations to persist. We measured infection dynamics of the fungal pathogen Pseudogymnoascus destructans that causes white-nose syndrome in bats by estimating pathogen prevalence and load in seven bat species at 167 hibernacula over a decade as the pathogen invaded, became established, and some host populations stabilized. Fungal loads increased rapidly and prevalence rose to nearly 100% at most sites within 2 yr of invasion in six of seven species. Prevalence and loads did not decline over time despite huge reductions in colony sizes, likely due to an extensive environmental reservoir. However, there was substantial variation in fungal load among sites with persisting colonies, suggesting that both tolerance and resistance developed at different sites in the same species. In contrast, one species disappeared from hibernacula within 3 yr of pathogen invasion. Variable host responses to pathogen invasion require different management strategies to prevent disease-induced extinction and to facilitate evolution of tolerance or resistance in persisting populations. © 2016 by the Ecological Society of America.

Omics Approaches for the Engineering of Pathogen Resistant Plants.

PubMed

Gomez-Casati, Diego F; Pagani, María A; Busi, María V; Bhadauria, Vijai

2016-01-01

The attack of different pathogens, such as bacteria, fungi and viruses has a negative impact on crop production. In counter such attacks, plants have developed different strategies involving the modification of gene expression, activation of several metabolic pathways and post-translational modification of proteins, which culminate into the accumulation of primary and secondary metabolites implicated in plant defense responses. The recent advancement in omics techniques allows the increase coverage of plants transcriptomes, proteomes and metabolomes during pathogen attack, and the modulation of the response after the infection. Omics techniques also allow us to learn more about the biological cycle of the pathogens in addition to the identification of novel virulence factors in pathogens and their host targets. Both approaches become important to decipher the mechanism underlying pathogen attacks and to develop strategies for improving disease-resistant plants. In this review, we summarize some of the contribution of genomics, transcriptomics, proteomics, metabolomics and metallomics in devising the strategies to obtain plants with increased resistance to pathogens. These approaches constitute important research tools in the development of new technologies for the protection against diseases and increase plant production.

GUIDE TO CLEANER TECHNOLOGIES: ORGANIC COATING REMOVAL

EPA Science Inventory

A cleaner technology is a source reduction or recycle method |applied to eliminate or significantly reduce hazardous waste generation. Source reduction includes product changes and source control. Source control can be further characterized as input material changes, technology...

Impact of pathogen-directed antimicrobial therapy for ventilator-associated pneumonia in trauma patients on charges and recurrence.

PubMed

Sharpe, John P; Magnotti, Louis J; Weinberg, Jordan A; Swanson, Joseph M; Wood, G Christopher; Fabian, Timothy C; Croce, Martin A

2015-04-01

Ventilator-associated pneumonia (VAP) represents one of the driving forces behind antibiotic use in the ICU. In a previous study, we established a defined algorithm for treatment of hospital-acquired VAP dictated by the causative pathogen. The purpose of the current study was to evaluate the impact of this algorithm for hospital-acquired VAP on recurrence and charges in trauma patients. Patients with VAP secondary to MRSA, Acinetobacter baumannii, Pseudomonas aeruginosa, Stenotrophomonas maltophilia, or Enterobacteriaceae during 5 years subsequent to the previous study were evaluated. All VAP were diagnosed using quantitative cultures of the bronchoalveolar lavage effluent. Duration of antimicrobial therapy was dictated by the causative pathogen. If microbiologic resolution, defined as <10(3) colony-forming units/mL, was achieved, therapy was stopped by day 10. The remainder received 14 days of therapy. Recurrence was defined as >10(5) colony-forming units/mL on subsequent bronchoalveolar lavage performed within 2 weeks after completion of appropriate therapy. Five hundred and twenty-nine VAP episodes were identified in 381 patients. Overall recurrence was unchanged compared with the previous study (1.5% vs 2%; p = 0.3). There was a decrease in the number of bronchoalveolar lavages performed per patient compared with the previous study (1.6 vs 2.3; p = 0.24) and a reduction of 4.8 antibiotic days per VAP episode compared with the previous study. Both changes resulted in a cumulative reduction of $3,535.04 per patient, for a savings of $1.35 million during the study period. Hospital-acquired VAP can be managed effectively by a defined course of therapy dictated by the causative pathogen. Adherence to an established algorithm simplified the management of VAP and contributed to a cumulative reduction in patient charges without impacting recurrence. Copyright © 2015 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

A pilot-scale microwave technology for sludge sanitization and drying.

PubMed

Mawioo, Peter M; Garcia, Hector A; Hooijmans, Christine M; Velkushanova, Konstantina; Simonič, Marjana; Mijatović, Ivan; Brdjanovic, Damir

2017-12-01

Large volumes of sludge are produced from onsite sanitation systems in densely populated areas (e.g. slums and emergency settlements) and wastewater treatment facilities that contain high amounts of pathogens. There is a need for technological options which can effectively treat the rapidly accumulating sludge under these conditions. This study explored a pilot-scale microwave (MW) based reactor as a possible alternative for rapid sludge treatment. The reactor performance was examined by conducting a series of batch tests using centrifuged waste activated sludge (C-WAS), non-centrifuged waste activated sludge (WAS), faecal sludge (FS), and septic tank sludge (SS). Four kilograms of each sludge type were subjected to MW treatment at a power of 3.4kW for various time durations ranging from 30 to 240min. During the treatment the temperature change, bacteria inactivation (E. coli, coliforms, Staphylococcus aureus, and enterococcus faecalis) and sludge weight/volume reduction were measured. Calorific values (CV) of the dried sludge and the nutrient content (total nitrogen (TN) and total phosphorus (TP)) in both the dried sludge and the condensate were also determined. It was found that MW treatment was successful to achieve a complete bacterial inactivation and a sludge weight/volume reduction above 60%. Besides, the dried sludge and condensate had high energy (≥16MJ/kg) and nutrient contents (solids; TN≥28mg/g TS and TP≥15mg/g TS; condensate TN≥49mg/L TS and TP≥0.2mg/L), having the potential to be used as biofuel, soil conditioner, fertilizer, etc. The MW reactor can be applied for the rapid treatment of sludge in areas such as slums and emergency settlements. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Effective and specific in planta RNAi in cyst nematodes: expression interference of four parasitism genes reduces parasitic success.

PubMed

Sindhu, Anoop S; Maier, Tom R; Mitchum, Melissa G; Hussey, Richard S; Davis, Eric L; Baum, Thomas J

2009-01-01

Cyst nematodes are highly evolved sedentary plant endoparasites that use parasitism proteins injected through the stylet into host tissues to successfully parasitize plants. These secretory proteins likely are essential for parasitism as they are involved in a variety of parasitic events leading to the establishment of specialized feeding cells required by the nematode to obtain nourishment. With the advent of RNA interference (RNAi) technology and the demonstration of host-induced gene silencing in parasites, a new strategy to control pests and pathogens has become available, particularly in root-knot nematodes. Plant host-induced silencing of cyst nematode genes so far has had only limited success but similarly should disrupt the parasitic cycle and render the host plant resistant. Additional in planta RNAi data for cyst nematodes are being provided by targeting four parasitism genes through host-induced RNAi gene silencing in transgenic Arabidopsis thaliana, which is a host for the sugar beet cyst nematode Heterodera schachtii. Here it is reported that mRNA abundances of targeted nematode genes were specifically reduced in nematodes feeding on plants expressing corresponding RNAi constructs. Furthermore, this host-induced RNAi of all four nematode parasitism genes led to a reduction in the number of mature nematode females. Although no complete resistance was observed, the reduction of developing females ranged from 23% to 64% in different RNAi lines. These observations demonstrate the relevance of the targeted parasitism genes during the nematode life cycle and, potentially more importantly, suggest that a viable level of resistance in crop plants may be accomplished in the future using this technology against cyst nematodes.

Antibacterial and efflux pump inhibitors of thymol and carvacrol against food-borne pathogens.

PubMed

Miladi, Hanene; Zmantar, Tarek; Chaabouni, Yassine; Fedhila, Kais; Bakhrouf, Amina; Mahdouani, Kacem; Chaieb, Kamel

2016-10-01

In this study thymol (THY) and carvacrol (CAR), two monoterpenic phenol produced by various aromatic plants, was tested for their antibacterial and efflux pump inhibitors potencies against a panel of clinical and foodborne pathogenes. Our results demonstrated a substantial susceptibility of the tested bacteria toward THY and CAR. Especially, THY displayed a strong inhibitory activity (MIC's values ranged from 32 to 64 μg/mL) against the majority of the tested strains compared to CAR. Moreover, a significant reduction in MIC's of TET and benzalkonium chloride (QAC) were noticed when tested in combinations with THY and CAR. Their synergic effect was more significant in the case of THY which resulted a reduction of MIC's values of TET (2-8 fold) and QAC (2-8 fold). We noted also that THY and CAR inhibited the ethidium bromide (EtBr) cell efflux in a concentration-dependent manner. The rate of EtBr accumulation in food-borne pathogen was enhanced with THY and CAR (0, 250 and 500 μg/mL). The lowest concentration causing 50% of EtBr efflux inhibition (IC 50) was noticed in Salmonella enteritidis (1129) at 150 μg/mL of THY and 190 μg/mL of CAR respectively. These findings indicate that THY and CAR may serve as potential sources of efflux pump inhibitor in food-borne pathogens. Copyright © 2016 Elsevier Ltd. All rights reserved.

Predators indirectly reduce the prevalence of an insect-vectored plant pathogen independent of predator diversity.

PubMed

Long, Elizabeth Y; Finke, Deborah L

2015-04-01

A widely cited benefit of predator diversity is greater suppression of insect herbivores, with corresponding increases in plant biomass. In the context of a vector-borne pathogen system, predator species richness may also influence plant disease risk via the direct effects of predators on the abundance and behavior of herbivores that also act as pathogen vectors. Using an assemblage of generalist insect predators, we examined the relationship between predator species richness and the prevalence of the aphid-vectored cereal yellow dwarf virus in wheat. We found that increasing predator richness enhanced suppression of the vector population and that pathogen prevalence was reduced when predators were present, but the reduction in prevalence was independent of predator species richness. To determine the mechanism(s) by which predator species richness contributes to vector suppression, but not pathogen prevalence, we evaluated vector movement and host plant occupancy in response to predator treatments. We found that pathogen prevalence was unrelated to vector suppression because host plant occupancy by vectors did not vary as a function of vector abundance. However, the presence of predators reduced pathogen prevalence because predators stimulated greater plant-to-plant movement by vectors, which likely diminished vector feeding time and reduced the transmission efficiency of this persistent pathogen. We conclude that community structure (i.e., the presence of predators), but not predator diversity, is a potential factor influencing local plant infection by this insect-vectored pathogen.

The Road to Infection: Host-Microbe Interactions Defining the Pathogenicity of Streptococcus bovis/Streptococcus equinus Complex Members

PubMed Central

Jans, Christoph; Boleij, Annemarie

2018-01-01

The Streptococcus bovis/Streptococcus equinus complex (SBSEC) comprises several species inhabiting the animal and human gastrointestinal tract (GIT). They match the pathobiont description, are potential zoonotic agents and technological organisms in fermented foods. SBSEC members are associated with multiple diseases in humans and animals including ruminal acidosis, infective endocarditis (IE) and colorectal cancer (CRC). Therefore, this review aims to re-evaluate adhesion and colonization abilities of SBSEC members of animal, human and food origin paired with genomic and functional host-microbe interaction data on their road from colonization to infection. SBSEC seem to be a marginal population during GIT symbiosis that can proliferate as opportunistic pathogens. Risk factors for human colonization are considered living in rural areas and animal-feces contact. Niche adaptation plays a pivotal role where Streptococcus gallolyticus subsp. gallolyticus (SGG) retained the ability to proliferate in various environments. Other SBSEC members have undergone genome reduction and niche-specific gene gain to yield important commensal, pathobiont and technological species. Selective colonization of CRC tissue is suggested for SGG, possibly related to increased adhesion to cancerous cell types featuring enhanced collagen IV accessibility. SGG can colonize, proliferate and may shape the tumor microenvironment to their benefit by tumor promotion upon initial neoplasia development. Bacteria cell surface structures including lipotheichoic acids, capsular polysaccharides and pilus loci (pil1, pil2, and pil3) govern adhesion. Only human blood-derived SGG contain complete pilus loci and other disease-associated surface proteins. Rumen or feces-derived SGG and other SBSEC members lack or harbor mutated pili. Pili also contribute to binding to fibrinogen upon invasion and translocation of cells from the GIT into the blood system, subsequent immune evasion, human contact system activation and collagen-I-binding on damaged heart valves. Only SGG carrying complete pilus loci seem to have highest IE potential in humans with significant links between SGG bacteremia/IE and underlying diseases including CRC. Other SBSEC host-microbe combinations might rely on currently unknown mechanisms. Comparative genome data of blood, commensal and food isolates are limited but required to elucidate the role of pili and other virulence factors, understand pathogenicity mechanisms, host specificity and estimate health risks for animals, humans and food alike. PMID:29692760

[Analysis of Pathogenic Bacteria in Reclaimed Water and Impact of UV Disinfection on the Removal of Pathogenic Bacteria].

PubMed

Jing, Ming; Wang, Lei

2016-02-15

In the study, 454-pyrosequencing technology was employed to investigate the species of pathogenic bacteria and the proportion of each pathogen in secondary effluent. Culture-based, qPCR and Q-RT-PCR methods were employed to analyze the removal of indicator (E. coli) and pathogen (Salmonella and Mycobacterium) by ultraviolet (UV) disinfection at a dose of 60 mJ x Cm(-2). The results showed that 11 kinds of pathogenic bacteria were found and the most abundant potentially pathogenic bacteria in the secondary effluent were affiliated with the genera of Clostridium (2.96%), Arcobacter (0.82%) and Mycobacterium (0.36%). 99.9% of culturable E. coli and Salmonella were removed by UV disinfection (60 mJ x cm(-2), however, less than 90% of culturable Mycobacterium were removed. The removal efficiencies of viable E. coli, Salmonella and Mycobacterium were low. Q-RT-PCR seemed to be a promising method for evaluating viable microorganisms in samples. Besides, pathogenic bacteria entered into VBNC state at a UV dose of 60 mJ x cm(-2). Other advanced treatment processes were needed to ensure safe utilization of reclaimed water.

Trans-Kingdom RNA Silencing in Plant-Fungal Pathogen Interactions.

PubMed

Hua, Chenlei; Zhao, Jian-Hua; Guo, Hui-Shan

2018-02-05

Fungal pathogens represent a major group of plant invaders that are the causative agents of many notorious plant diseases. Large quantities of RNAs, especially small RNAs involved in gene silencing, have been found to transmit bidirectionally between fungal pathogens and their hosts. Although host-induced gene silencing (HIGS) technology has been developed and applied to protect crops from fungal infections, the mechanisms of RNA transmission, especially small RNAs regulating trans-kingdom RNA silencing in plant immunity, are largely unknown. In this review, we summarize and discuss recent important findings regarding trans-kingdom sRNAs and RNA silencing in plant-fungal pathogen interactions compared with the well-known RNAi mechanisms in plants and fungi. We focus on the interactions between plant and fungal pathogens with broad hosts, represented by the vascular pathogen Verticillium dahliae and non-vascular pathogen Botrytis cinerea, and discuss the known instances of natural RNAi transmission between fungal pathogens and host plants. Given that HIGS has been developed and recently applied in controlling Verticillium wilt diseases, we propose an ideal research system exploiting plant vasculature-Verticillium interaction to further study trans-kingdom RNA silencing. Copyright © 2017 The Author. Published by Elsevier Inc. All rights reserved.

The application of food safety interventions in primary production of beef and lamb: a review.

PubMed

Adam, K; Brülisauer, F

2010-07-31

The production of safe red meat depends on effective control of pathogenic microorganisms at all stages of the "farm-to-fork" chain. Eight microorganisms have been selected as the focus of the PathogenCombat project: Shiga toxin producing Escherichia coli (STEC), Mycobacterium avium subspecies paratuberculosis (Map), Listeria monocytogenes, Campylobacter jejuni, Penicillium nordicum, invasive variants of Saccharomyces cerevisiae, hepatitis E virus and tick borne encephalitis virus. The need and potential for coordinated control of the selected food-borne pathogens by on-farm interventions is assessed using a decision tree and a review of the relevant scientific literature. Control measures to reduce the carriage of these pathogens in ruminants prior to slaughter are reviewed with reference to the current regulations and guidelines relating to the primary production. From the eight pathogens investigated, two (STEC and Map), are likely to be effectively controlled by interventions at farm level and the applicable interventions are described and discussed. Ruminants are the main reservoir for these two pathogens; hence a reduction of carriage in livestock should directly reduce human exposure through the consumption of beef and lamb. Copyright 2009 Elsevier B.V. All rights reserved.

Single-cell technologies to study the immune system.

PubMed

Proserpio, Valentina; Mahata, Bidesh

2016-02-01

The immune system is composed of a variety of cells that act in a coordinated fashion to protect the organism against a multitude of different pathogens. The great variability of existing pathogens corresponds to a similar high heterogeneity of the immune cells. The study of individual immune cells, the fundamental unit of immunity, has recently transformed from a qualitative microscopic imaging to a nearly complete quantitative transcriptomic analysis. This shift has been driven by the rapid development of multiple single-cell technologies. These new advances are expected to boost the detection of less frequent cell types and transient or intermediate cell states. They will highlight the individuality of each single cell and greatly expand the resolution of current available classifications and differentiation trajectories. In this review we discuss the recent advancement and application of single-cell technologies, their limitations and future applications to study the immune system. © 2015 The Authors. Immunology Published by John Wiley & Sons Ltd.

Peracetic acid as an alternative disinfection technology for wet weather flows.

PubMed

Coyle, Elizabeth E; Ormsbee, Lindell E; Brion, Gail M

2014-08-01

Rain-induced wet weather flows (WWFs) consist of combined sewer overflows, sanitary sewer overflows, and stormwater, all of which introduce pathogens to surface waters when discharged. When people come into contact with the contaminated surface water, these pathogens can be transmitted resulting in severe health problems. As such, WWFs should be disinfected. Traditional disinfection technologies are typically cost-prohibitive, can yield toxic byproducts, and space for facilities is often limited, if available. More cost-effective alternative technologies, requiring less space and producing less harmful byproducts are currently being explored. Peracetic acid (PAA) was investigated as one such alternative and this research has confirmed the feasibility and applicability of using PAA as a disinfectant for WWFs. Peracetic acid doses ranging from 5 mg/L to 15 mg/L over contact times of 2 to 10 minutes were shown to be effective and directly applicable to WWF disinfection.

Inactivation of viruses and bacteria on strawberries using a levulinic acid plus sodium dodecyl sulfate based sanitizer, taking sensorial and chemical food safety aspects into account.

PubMed

Zhou, Zijin; Zuber, Sophie; Cantergiani, Frédérique; Butot, Sophie; Li, Dan; Stroheker, Thomas; Devlieghere, Frank; Lima, Anthony; Piantini, Umberto; Uyttendaele, Mieke

2017-09-18

The efficacy of levulinic acid (LVA) in combination with sodium dodecyl sulfate (SDS) in removal of foodborne viruses, enteric bacterial pathogens and their surrogates on fresh strawberries was investigated. Inoculated strawberries were treated with potable water, sodium hypochlorite solution (50ppm), 0.5% LVA plus 0.5% SDS solution, and 5% LVA plus 2% SDS solution respectively for 2min, followed by spray-rinsing with potable water. Water washing removed at least 1.0-log of the tested viral and bacterial strains from the strawberries' surfaces. The 50ppm chlorine wash induced 3.4, 1.5 and 2.1-log reductions for hepatitis A virus (HAV), murine norovirus-1 (MNV-1) and MS2 bacteriophage, respectively. In comparison, the tested bacterial strains showed uniform reductions around 1.6-log CFU/ml. The 0.5% LVA plus 0.5% SDS wash induced 2.7, 1.4 and 2.4-log reductions for HAV, MNV-1 and MS2, which were comparable with the reductions induced by chlorine (P>0.05). For bacteria, over 2.0-log reductions were obtained for Enterococcus faecium, Listeria monocytogenes and Salmonella, while Escherichia coli O157:H7 and Escherichia coli P1 showed reductions of 1.9 and 1.8-log CFU/ml. Higher concentration of LVA plus SDS showed no significantly higher reductions (P>0.05). Sensory tests of washed strawberries and chemical residue analysis of LVA on strawberries after washing were also performed. In conclusion, this study demonstrates good performance of 0.5% LVA plus 0.5% SDS to reduce the levels of enteric pathogens if present on strawberries without altering taste and introducing chemical safety issues. Copyright © 2017 Elsevier B.V. All rights reserved.

Carbon Dioxide Reduction Technology Trade Study

NASA Technical Reports Server (NTRS)

Jeng, Frank F.; Anderson, Molly S.; Abney, Morgan B.

2011-01-01

For long-term human missions, a closed-loop atmosphere revitalization system (ARS) is essential to minimize consumables. A carbon dioxide (CO2) reduction technology is used to reclaim oxygen (O2) from metabolic CO2 and is vital to reduce the delivery mass of metabolic O2. A key step in closing the loop for ARS will include a proper CO2 reduction subsystem that is reliable and with low equivalent system mass (ESM). Sabatier and Bosch CO2 reduction are two traditional CO2 reduction subsystems (CRS). Although a Sabatier CRS has been delivered to International Space Station (ISS) and is an important step toward closing the ISS ARS loop, it recovers only 50% of the available O2 in CO2. A Bosch CRS is able to reclaim all O2 in CO2. However, due to continuous carbon deposition on the catalyst surface, the penalties of replacing spent catalysts and reactors and crew time in a Bosch CRS are significant. Recently, technologies have been developed for recovering hydrogen (H2) from Sabatier-product methane (CH4). These include methane pyrolysis using a microwave plasma, catalytic thermal pyrolysis of CH4 and thermal pyrolysis of CH4. Further, development in Sabatier reactor designs based on microchannel and microlith technology could open up opportunities in reducing system mass and enhancing system control. Improvements in Bosch CRS conversion have also been reported. In addition, co-electrolysis of steam and CO2 is a new technology that integrates oxygen generation and CO2 reduction functions in a single system. A co-electrolysis unit followed by either a Sabatier or a carbon formation reactor based on Bosch chemistry could improve the overall competitiveness of an integrated O2 generation and CO2 reduction subsystem. This study evaluates all these CO2 reduction technologies, conducts water mass balances for required external supply of water for 1-, 5- and 10-yr missions, evaluates mass, volume, power, cooling and resupply requirements of various technologies. A system analysis and comparison among the technologies was made based on ESM, technology readiness level and reliability. Those technologies with potential were recommended for development.

MODELING HOST-PATHOGEN INTERACTIONS: COMPUTATIONAL BIOLOGY AND BIOINFORMATICS FOR INFECTIOUS DISEASE RESEARCH (Session introduction)

DOE Office of Scientific and Technical Information (OSTI.GOV)

McDermott, Jason E.; Braun, Pascal; Bonneau, Richard A.

Pathogenic infections are a major cause of both human disease and loss of crop yields and animal stocks and thus cause immense damage to the worldwide economy. The significance of infectious diseases is expected to increase in an ever more connected warming world, in which new viral, bacterial and fungal pathogens can find novel hosts and ecologic niches. At the same time, the complex and sophisticated mechanisms by which diverse pathogenic agents evade defense mechanisms and subvert their hosts networks to suit their lifestyle needs is still very incompletely understood especially from a systems perspective [1]. Thus, understanding host-pathogen interactionsmore » is both an important and a scientifically fascinating topic. Recently, technology has offered the opportunity to investigate host-pathogen interactions on a level of detail and scope that offers immense computational and analytical possibilities. Genome sequencing was pioneered on some of these pathogens, and the number of strains and variants of pathogens sequenced to date vastly outnumbers the number of host genomes available. At the same time, for both plant and human hosts more and more data on population level genomic variation becomes available and offers a rich field for analysis into the genetic interactions between host and pathogen.« less

Autoheated thermophilic aerobic digestion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Deeny, K.; Hahn, H.; Leonhard, D.

1991-10-01

Autothermal thermophilic aerobic digestion (ATAD) is first and foremost a digestion process, the primary purpose of which is to decompose a portion of the waste organic solids generated from wastewater treatment. As a result of the high operating temperature, digestion is expected to occur within a short time period (6 days) and accomplish a high degree of pathogen reduction. ATAD systems are two-stage aerobic digestion processes that operate under thermophilic temperature conditions (40 to 80C) without supplemental heat. Like composting, the systems rely on the conservation of heat released during digestion itself to attain and sustain the desired operating temperature.more » Typical ATAD systems operate at 55C and may reach temperatures of 60 to 65C in the second-stage reactor. Perhaps because of the high operating temperature, this process has been referred to as Liquid Composting.' Major advantages associated with thermophilic operation include high biological reaction rates and a substantial degree of pathogen reduction.« less

Chemical generation of nitric oxide in the mouth from the enterosalivary circulation of dietary nitrate.

PubMed

Duncan, C; Dougall, H; Johnston, P; Green, S; Brogan, R; Leifert, C; Smith, L; Golden, M; Benjamin, N

1995-06-01

High concentrations of nitrite present in saliva (derived from dietary nitrate) may, upon acidification, generate nitrogen oxides in the stomach in sufficient amounts to provide protection from swallowed pathogens. We now show that, in the rat, reduction of nitrate to nitrite is confined to a specialized area on the posterior surface of the tongue, which is heavily colonized by bacteria, and that nitrate reduction is absent in germ-free rats. We also show that in humans increased salivary nitrite production resulting from nitrate intake enhances oral nitric oxide production. We propose that the salivary generation of nitrite is accomplished by a symbiotic relationship involving nitrate-reducing bacteria on the tongue surface, which is designed to provide host defence against microbial pathogens in the mouth and lower gut. These results provide further evidence for beneficial effects of dietary nitrate.

Recent Progress in Engine Noise Reduction Technologies

NASA Technical Reports Server (NTRS)

Huff, Dennis; Gliebe, Philip

2003-01-01

Highlights from NASA-funded research over the past ten years for aircraft engine noise reduction are presented showing overall technical plans, accomplishments, and selected applications to turbofan engines. The work was sponsored by NASA's Advanced Subsonic Technology (AST) Noise Reduction Program. Emphasis is given to only the engine noise reduction research and significant accomplishments that were investigated at Technology Readiness Levels ranging from 4 to 6. The Engine Noise Reduction sub-element was divided into four work areas: source noise prediction, model scale tests, engine validation, and active noise control. Highlights from each area include technologies for higher bypass ratio turbofans, scarf inlets, forward-swept fans, swept and leaned stators, chevron/tabbed nozzles, advanced noise prediction analyses, and active noise control for fans. Finally, an industry perspective is given from General Electric Aircraft Engines showing how these technologies are being applied to commercial products. This publication contains only presentation vu-graphs from an invited lecture given at the 41st AIAA Aerospace Sciences Meeting, January 6-9, 2003.

A Probabilistic Assessment of NASA Ultra-Efficient Engine Technologies for a Large Subsonic Transport

NASA Technical Reports Server (NTRS)

Tong, Michael T.; Jones, Scott M.; Arcara, Philip C., Jr.; Haller, William J.

2004-01-01

NASA's Ultra Efficient Engine Technology (UEET) program features advanced aeropropulsion technologies that include highly loaded turbomachinery, an advanced low-NOx combustor, high-temperature materials, intelligent propulsion controls, aspirated seal technology, and an advanced computational fluid dynamics (CFD) design tool to help reduce airplane drag. A probabilistic system assessment is performed to evaluate the impact of these technologies on aircraft fuel burn and NOx reductions. A 300-passenger aircraft, with two 396-kN thrust (85,000-pound) engines is chosen for the study. The results show that a large subsonic aircraft equipped with the UEET technologies has a very high probability of meeting the UEET Program goals for fuel-burn (or equivalent CO2) reduction (15% from the baseline) and LTO (landing and takeoff) NOx reductions (70% relative to the 1996 International Civil Aviation Organization rule). These results are used to provide guidance for developing a robust UEET technology portfolio, and to prioritize the most promising technologies required to achieve UEET program goals for the fuel-burn and NOx reductions.

Developmement of second-generation Environmentally Superior Technology for treatment of swine manure in the USA

USDA-ARS?s Scientific Manuscript database

New swine waste management systems in North Carolina need to meet high performance standards of an environmentally superior technology (EST) regarding nitrogen, phosphorus, heavy metals, pathogens, ammonia and odor emissions, and remain affordable and simple to operate. The objective of this study w...

Microbial Protein-Antigenome Determination (MAD) Technology: A Proteomics-Based Strategy for Rapid Identification of Microbial Targets of Host Humoral Immune Responses

USDA-ARS?s Scientific Manuscript database

Immunogenic, pathogen-specific proteins have excellent potential for development of novel management modalities. Here, we describe an innovative application of proteomics called Microbial protein-Antigenome Determination (MAD) Technology for rapid identification of native microbial proteins that el...

Microbial Protein-Antigenome Determination (MAD) Technology: A Proteomics-Based Strategy for Rapid Identification of Microbial Targets of Host Humoral Immune Responses

USDA-ARS?s Scientific Manuscript database

Immunogenic, pathogen-specific proteins have excellent potential for development of novel management modalities. Here, we describe an innovative application of proteomics called Microbial protein-Antigenome Determination (MAD) Technology for rapid identification of native microbial proteins that eli...

Helicase-dependent isothermal amplification: a novel tool in the development of molecular-based analytical systems for rapid pathogen detection.

PubMed

Barreda-García, Susana; Miranda-Castro, Rebeca; de-Los-Santos-Álvarez, Noemí; Miranda-Ordieres, Arturo J; Lobo-Castañón, María Jesús

2018-01-01

Highly sensitive testing of nucleic acids is essential to improve the detection of pathogens, which pose a major threat for public health worldwide. Currently available molecular assays, mainly based on PCR, have a limited utility in point-of-need control or resource-limited settings. Consequently, there is a strong interest in developing cost-effective, robust, and portable platforms for early detection of these harmful microorganisms. Since its description in 2004, isothermal helicase-dependent amplification (HDA) has been successfully applied in the development of novel molecular-based technologies for rapid, sensitive, and selective detection of viruses and bacteria. In this review, we highlight relevant analytical systems using this simple nucleic acid amplification methodology that takes place at a constant temperature and that is readily compatible with microfluidic technologies. Different strategies for monitoring HDA amplification products are described. In addition, we present technological advances for integrating sample preparation, HDA amplification, and detection. Future perspectives and challenges toward point-of-need use not only for clinical diagnosis but also in food safety testing and environmental monitoring are also discussed. Graphical Abstract Expanding the analytical toolbox for the detection of DNA sequences specific of pathogens with isothermal helicase dependent amplification (HDA).

Screening for Intellectual Disability Using High-Resolution CMA Technology in a Retrospective Cohort from Central Brazil

PubMed Central

Pereira, Rodrigo Roncato; Pinto, Irene Plaza; Minasi, Lysa Bernardes; de Melo, Aldaires Vieira; da Cruz e Cunha, Damiana Mirian; Cruz, Alex Silva; Ribeiro, Cristiano Luiz; da Silva, Cláudio Carlos; de Melo e Silva, Daniela; da Cruz, Aparecido Divino

2014-01-01

Intellectual disability is a complex, variable, and heterogeneous disorder, representing a disabling condition diagnosed worldwide, and the etiologies are multiple and highly heterogeneous. Microscopic chromosomal abnormalities and well-characterized genetic conditions are the most common causes of intellectual disability. Chromosomal Microarray Analysis analyses have made it possible to identify putatively pathogenic copy number variation that could explain the molecular etiology of intellectual disability. The aim of the current study was to identify possible submicroscopic genomic alterations using a high-density chromosomal microarray in a retrospective cohort of patients with otherwise undiagnosable intellectual disabilities referred by doctors from the public health system in Central Brazil. The CytoScan HD technology was used to detect changes in the genome copy number variation of patients who had intellectual disability and a normal karyotype. The analysis detected 18 CNVs in 60% of patients. Pathogenic CNVs represented about 22%, so it was possible to propose the etiology of intellectual disability for these patients. Likely pathogenic and unknown clinical significance CNVs represented 28% and 50%, respectively. Inherited and de novo CNVs were equally distributed. We report the nature of CNVs in patients from Central Brazil, representing a population not yet screened by microarray technologies. PMID:25061755

Technologies and mechanisms for safety control of ready-to-eat muscle foods: an updated review.

PubMed

Jiang, Jiang; Xiong, Youling L

2015-01-01

Ready-to-eat (RTE) muscle foods refer to a general category of meat and poultry products that are fully cooked and consumable without reheating. These products, including whole and sliced pork, beef, turkey, chicken, and variety of meats, in the forms of ham, roast, rolls, sausage, and frankfurter, are widely available in the delicatessen section of retail stores or various food service outlets. However, difficulties in avoidance of contamination by foodborne pathogens, notably Listeria monocytogenes, during product postlethality repackaging render RTE meats labile to outbreaks. Accordingly, the USDA-FSIS has established processing guidelines and regulations, which are constantly updated, to minimize foodborne pathogens in RTE products. Technologies that complement good manufacturing practice have been developed to control RTE meat safety. Among them, various antimicrobial product formulations, postpackaging pasteurization (thermal and nonthermal), and antimicrobial packaging are being used. Through these efforts, outbreaks linked to RTE meat consumption have substantially reduced in recent years. However, the pervasive and virulent nature of L. monocytogenes and the possible presence of other cold-tolerant pathogens entail continuing developments of new intervention technologies. This review updates existing and emerging physical and chemical methods and their mode of action to inactivate or inhibit threatening microorganisms in RTE muscle foods.

Microbial Interactions in Plants: Perspectives and Applications of Proteomics.

PubMed

Imam, Jahangir; Shukla, Pratyoosh; Mandal, Nimai Prasad; Variar, Mukund

2017-01-01

The structure and function of proteins involved in plant-microbe interactions is investigated through large-scale proteomics technology in a complex biological sample. Since the whole genome sequences are now available for several plant species and microbes, proteomics study has become easier, accurate and huge amount of data can be generated and analyzed during plant-microbe interactions. Proteomics approaches are highly important and relevant in many studies and showed that only genomics approaches are not sufficient enough as much significant information are lost as the proteins and not the genes coding them are final product that is responsible for the observed phenotype. Novel approaches in proteomics are developing continuously enabling the study of the various aspects in arrangements and configuration of proteins and its functions. Its application is becoming more common and frequently used in plant-microbe interactions with the advancement in new technologies. They are more used for the portrayal of cell and extracellular destructiveness and pathogenicity variables delivered by pathogens. This distinguishes the protein level adjustments in host plants when infected with pathogens and advantageous partners. This review provides a brief overview of different proteomics technology which is currently available followed by their exploitation to study the plant-microbe interaction. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Evaluation of the potential of Trichoderma viride in the control of fungal pathogens of Roselle (Hibiscus sabdariffa L.) in vitro.

PubMed

Eslaminejad Parizi, T; Ansaria, Mehdi; Elaminejad, Tahereh

2012-04-01

The potential of Trichoderma viride as a bio-control agent was evaluated in vitro against Roselle pathogens i.e. Phoma exigua, Fusarium nygamai and Rhizoctonia solani[1] using the dual culture technique. Volatile and non-volatile inhibitors of Trichoderma were also evaluated for this purpose. T. viride[2] was shown to have a marked inhibitory effect on the tested pathogens in vitro. Maximum inhibition occurred against P. exigua, with 71.76% reduction in mycelial radial growth. The three pathogens, P. exigua, F. nygamai and R. solani were also found to be susceptible to the volatile inhibitors produced by T. viride, giving rise to growth inhibition of about 68% in each case. When T. viride non-volatile metabolites were tested against the pathogens, maximum inhibition occurred against R. solani (73.95% mycelial growth inhibition), followed by P. exigua (37.17% inhibition). The inhibitory effect of the non-volatile metabolites on F. nygamai was, however, minimal. Copyright © 2012 Elsevier Ltd. All rights reserved.

Bacterial community analysis of swine manure treated with autothermal thermophilic aerobic digestion.

PubMed

Han, Il; Congeevaram, Shankar; Ki, Dong-Won; Oh, Byoung-Taek; Park, Joonhong

2011-02-01

Due to the environmental problems associated with disposal of livestock sludge, many stabilization studies emphasizing on the sludge volume reduction were performed. However, little is known about the microbial risk present in sludge and its stabilized products. This study microbiologically explored the effects of anaerobic lagoon fermentation (ALF) and autothermal thermophilic aerobic digestion (ATAD) on pathogen-related risk of raw swine manure by using culture-independent 16S rDNA cloning and sequencing methods. In raw swine manure, clones closely related to pathogens such as Dialister pneumosintes, Erysipelothrix rhusiopathiae, Succinivibrioan dextrinosolvens, and Schineria sp. were detected. Meanwhile, in the mesophilic ALF-treated swine manure, bacterial community clones closely related to pathogens such as Schineria sp. and Succinivibrio dextrinosolvens were still detected. Interestingly, the ATAD treatment resulted in no detection of clones closely related to pathogens in the stabilized thermophilic bacterial community, with the predominance of novel Clostridia class populations. These findings support the superiority of ATAD in selectively reducing potential human and animal pathogens compared to ALF, which is a typical manure stabilization method used in livestock farms.

Resistance in persisting bat populations after white-nose syndrome invasion.

PubMed

Langwig, Kate E; Hoyt, Joseph R; Parise, Katy L; Frick, Winifred F; Foster, Jeffrey T; Kilpatrick, A Marm

2017-01-19

Increases in anthropogenic movement have led to a rise in pathogen introductions and the emergence of infectious diseases in naive host communities worldwide. We combined empirical data and mathematical models to examine changes in disease dynamics in little brown bat (Myotis lucifugus) populations following the introduction of the emerging fungal pathogen Pseudogymnoascus destructans, which causes the disease white-nose syndrome. We found that infection intensity was much lower in persisting populations than in declining populations where the fungus has recently invaded. Fitted models indicate that this is most consistent with a reduction in the growth rate of the pathogen when fungal loads become high. The data are inconsistent with the evolution of tolerance or an overall reduced pathogen growth rate that might be caused by environmental factors. The existence of resistance in some persisting populations of little brown bats offers a glimmer of hope that a precipitously declining species will persist in the face of this deadly pathogen.This article is part of the themed issue 'Human influences on evolution, and the ecological and societal consequences'. © 2016 The Author(s).

Omics markers of the red cell storage lesion and metabolic linkage

PubMed Central

D’Alessandro, Angelo; Nemkov, Travis; Reisz, Julie; Dzieciatkowska, Monika; Wither, Matthew J.; Hansen, Kirk C.

2017-01-01

The introduction of omics technologies in the field of Transfusion Medicine has significantly advanced our understanding of the red cell storage lesion. While the clinical relevance of such a lesion is still a matter of debate, quantitative and redox proteomics approaches, as well quantitative metabolic flux analysis and metabolic tracing experiments promise to revolutionise our understanding of the role of blood processing strategies, inform the design and testing of novel additives or technologies (such as pathogen reduction), and evaluate the clinical relevance of donor and recipient biological variability with respect to red cell storability and transfusion outcomes. By reviewing existing literature in this rapidly expanding research endeavour, we highlight for the first time a correlation between metabolic markers of the red cell storage age and protein markers of haemolysis. Finally, we introduce the concept of metabolic linkage, i.e. the appreciation of a network of highly correlated small molecule metabolites which results from biochemical constraints of erythrocyte metabolic enzyme activities. For the foreseeable future, red cell studies will advance Transfusion Medicine and haematology by addressing the alteration of metabolic linkage phenotypes in response to stimuli, including, but not limited to, storage additives, enzymopathies (e.g. glucose 6-phosphate dehydrogenase deficiency), hypoxia, sepsis or haemorrhage. PMID:28263171

Lawrence Livermore National Laboratory Workshop Characterization of Pathogenicity, Virulence and Host-Pathogen Interactions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Krishnan, A

2006-08-30

The threats of bio-terrorism and newly emerging infectious diseases pose serious challenges to the national security infrastructure. Rapid detection and diagnosis of infectious disease in human populations, as well as characterizing pathogen biology, are critical for reducing the morbidity and mortality associated with such threats. One of the key challenges in managing an infectious disease outbreak, whether through natural causes or acts of overt terrorism, is detection early enough to initiate effective countermeasures. Much recent attention has been directed towards the utility of biomarkers or molecular signatures that result from the interaction of the pathogen with the host for improvingmore » our ability to diagnose and mitigate the impact of a developing infection during the time window when effective countermeasures can be instituted. Host responses may provide early signals in blood even from localized infections. Multiple innate and adaptive immune molecules, in combination with other biochemical markers, may provide disease-specific information and new targets for countermeasures. The presence of pathogen specific markers and an understanding of the molecular capabilities and adaptations of the pathogen when it interacts with its host may likewise assist in early detection and provide opportunities for targeting countermeasures. An important question that needs to be addressed is whether these molecular-based approaches will prove useful for early diagnosis, complement current methods of direct agent detection, and aid development and use of countermeasures. Lawrence Livermore National Laboratory (LLNL) will host a workshop to explore the utility of host- and pathogen-based molecular diagnostics, prioritize key research issues, and determine the critical steps needed to transition host-pathogen research to tools that can be applied towards a more effective national bio-defense strategy. The workshop will bring together leading researchers/scientists in the area of host-pathogen interactions as well as policy makers from federal agencies. The main objectives of the workshop are: (1) to assess the current national needs, capabilities, near-term technologies, and future challenges in applying various diagnostics tools to public health and bio-defense; (2) to evaluate the utility and feasibility of host-response and pathogen biomarker profiling in the diagnosis and management of infectious diseases; and (3) to create a comprehensive developmental strategy from proof-of-concept, through validation, to deployment of appropriate advanced technology for the clinical/public health and bio-defense environments.« less

Pathogenomics: an updated European Research Agenda.

PubMed

Demuth, Andreas; Aharonowitz, Yair; Bachmann, Till T; Blum-Oehler, Gabriele; Buchrieser, Carmen; Covacci, Antonello; Dobrindt, Ulrich; Emödy, Levente; van der Ende, Arie; Ewbank, Jonathan; Fernández, Luis Angel; Frosch, Matthias; García-Del Portillo, Francisco; Gilmore, Michael S; Glaser, Philippe; Goebel, Werner; Hasnain, Seyed E; Heesemann, Jürgen; Islam, Khalid; Korhonen, Timo; Maiden, Martin; Meyer, Thomas F; Montecucco, Cesare; Oswald, Eric; Parkhill, Julian; Pucciarelli, M Graciela; Ron, Eliora; Svanborg, Catharina; Uhlin, Bernt Eric; Wai, Sun Nyunt; Wehland, Jürgen; Hacker, Jörg

2008-05-01

The emerging genomic technologies and bioinformatics provide novel opportunities for studying life-threatening human pathogens and to develop new applications for the improvement of human and animal health and the prevention, treatment, and diagnosis of infections. Based on the ecology and population biology of pathogens and related organisms and their connection to epidemiology, more accurate typing technologies and approaches will lead to better means of disease control. The analysis of the genome plasticity and gene pools of pathogenic bacteria including antigenic diversity and antigenic variation results in more effective vaccines and vaccine implementation programs. The study of newly identified and uncultivated microorganisms enables the identification of new threats. The scrutiny of the metabolism of the pathogen in the host allows the identification of new targets for anti-infectives and therapeutic approaches. The development of modulators of host responses and mediators of host damage will be facilitated by the research on interactions of microbes and hosts, including mechanisms of host damage, acute and chronic relationships as well as commensalisms. The study of multiple pathogenic and non-pathogenic microbes interacting in the host will improve the management of multiple infections and will allow probiotic and prebiotic interventions. Needless to iterate, the application of the results of improved prevention and treatment of infections into clinical tests will have a positive impact on the management of human and animal disease. The Pathogenomics Research Agenda draws on discussions with experts of the Network of Excellence "EuroPathoGenomics" at the management board meeting of the project held during 18-21 April 2007, in the Villa Vigoni, Menaggio, Italy. Based on a proposed European Research Agenda in the field of pathogenomics by the ERA-NET PathoGenoMics the meeting's participants updated the established list of topics as the research agenda for the future.

Controlling Microbial Safety Challenges of Meat Using High Voltage Atmospheric Cold Plasma

PubMed Central

Han, Lu; Ziuzina, Dana; Heslin, Caitlin; Boehm, Daniela; Patange, Apurva; Sango, David M.; Valdramidis, Vasilis P.; Cullen, Patrick J.; Bourke, Paula

2016-01-01

Atmospheric cold plasma (ACP) is a non-thermal technology, effective against a wide range of pathogenic microorganisms. Inactivation efficacy results from plasma generated reactive species. These may interact with any organic components in a test matrix including the target microorganism, thus food components may exert a protective effect against the antimicrobial mode of action. The effect of an in-package high voltage ACP process applied in conjunction with common meat processing MAP gas compositions as well as bacteria type and meat model media composition have been investigated to determine the applicability of this technology for decontamination of safety challenges associated with meat products. E. coli, L. monocytogenes, and S. aureus in PBS were undetectable after 60 s of treatment at 80 kVRMS in air, while ACP treatment of the contaminated meat model required post-treatment refrigeration to retain antimicrobial effect. The nutritive components in the meat model exerted a protective effect during treatment, where 300 s ACP exposure yielded a maximum reduction of 1.5 log using a high oxygen atmosphere, whilst using air and high nitrogen atmospheres yielded lower antimicrobial efficacy. Furthermore, an ROS assay was performed to understand the protective effects observed using the meat model. This revealed that nutritive components inhibited penetration of ROS into bacterial cells. This knowledge can assist the optimization of meat decontamination using ACP technology where interactions with all components of the food matrix require evaluation. PMID:27446018

Primary Hemostatic Capacity of Whole Blood: A Comprehensive Analysis of Pathogen Reduction and Refrigeration Effects Over Time

DTIC Science & Technology

2013-01-01

reduction and refrigeration is intriguing and suggests that PRT WB may complement the beneficial effects of the antifibrinolytic, tranexamic acid in...and ABBREVIATIONS: aPTT = activated partial thromboplastin time; ASPI = arachidonic acid agonist; COL = collagen; GPIba = glycoprotein Ib alpha; K...riboflavin and ultraviolet (UV) light to damage the nucleic acids of white blood cells (WBCs), parasites, bacteria, and viruses, is being consid- ered

COST OF SELECTIVE CATALYTIC REDUCTION (SCR) APPLICATION FOR NOX CONTROL ON COAL-FIRED BOILERS

EPA Science Inventory

The report provides a methodology for estimating budgetary costs associated with retrofit applications of selective catalytic reduction (SCR) technology on coal-fired boilers. SCR is a postcombustion nitrogen oxides (NOx) control technology capable of providing NOx reductions >90...

An overview of spray drift reduction testing of spray nozzles

USDA-ARS?s Scientific Manuscript database

The importance of the development and testing of drift reduction technologies (DRTs) is increasing. Common spray drift reduction technologies include spray nozzles and spray adjuvants. Following draft procedures developed for a DRT program, three spray nozzles were tested under high air speed cond...