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News Article | May 12, 2017
Site: www.eurekalert.org

Washington, DC - May 12, 2017 - A team of researchers from the United Kingdom has developed a novel method for assessing human/pathogen interactions in the natural environment, using citizen scientists wearing boot socks over their shoes during walks in the countryside. In the process, they found that slightly less than half of the socks were positive for the gastrointestinal pathogen, Campylobacter. The research is published in Applied and Environmental Microbiology, a journal of the American Society for Microbiology. In the study, groups of volunteer walkers wearing boot socks on one foot took regular four kilometer (two and a half mile) walks on each of six pathways in the countryside, over a 16 month period. The pathways are located in two regions of the UK, the livestock-dominated North West, and East Anglia, much of which is devoted to cropland, said coauthor Natalia Jones, PhD, Senior Research Associate, University of East Anglia. Following the walks, the walkers mailed the socks to the lab, where coauthors used microbial culture and PCR methods to determine the presence, and species of Campylobacter. As measured on boot socks, Campylobacter was more prevalent in livestock-dominated North West than in East Anglia (55.8% of socks, vs 38.6%). Campylobacter peaked during winter in both regions, and peaked again in spring in North West. Precipitation was associated with greater Campylobacter, and higher temperatures with less. The results "are consistent with our understanding of Campylobacter survival and the probability of material adhering to boot socks," according to the report. C. jejuni was the most commonly found species, with C. coli largely restricted to the livestock dominated North West, according to the report. Source attribution analysis suggested that the major source of C. jejuni was sheep in North West, and wild birds in East Anglia. The motivation for the study was the desire to develop an efficient sampling method to explore the potential for transfer of Campylobacter from the environment to humans through visits to the countryside, and to determine whether any such risk varied seasonally, said Jones. Campylobacter is the most common bacterial cause of diarrheal disease in the developed world. "It is known that food is often a source of Campylobacter infections in humans, but we also know that exposure through food cannot explain all the cases seen in the human population," said Jones. "Exploring other potential routes was a key motivation." Conventional sampling is based on sampling from a single point, called spot sampling, and does not sample human-pathogen interactions. "Ultimately, this research could lead to interventions to reduce the risk to humans," said Jones. The American Society for Microbiology is the largest single life science society, composed of over 50,000 scientists and health professionals. ASM's mission is to promote and advance the microbial sciences. ASM advances the microbial sciences through conferences, publications, certifications and educational opportunities. It enhances laboratory capacity around the globe through training and resources. It provides a network for scientists in academia, industry and clinical settings. Additionally, ASM promotes a deeper understanding of the microbial sciences to diverse audiences.


A team of researchers from the United Kingdom has developed a novel method for assessing human/pathogen interactions in the natural environment, using citizen scientists wearing boot socks over their shoes during walks in the countryside. In the process, they found that slightly less than half of the socks were positive for the gastrointestinal pathogen, Campylobacter. The research is published in Applied and Environmental Microbiology, a journal of the American Society for Microbiology. In the study, groups of volunteer walkers wearing boot socks on one foot took regular four kilometer (two and a half mile) walks on each of six pathways in the countryside, over a 16 month period. The pathways are located in two regions of the UK, the livestock-dominated North West, and East Anglia, much of which is devoted to cropland, said coauthor Natalia Jones, PhD, Senior Research Associate, University of East Anglia. Following the walks, the walkers mailed the socks to the lab, where coauthors used microbial culture and PCR methods to determine the presence, and species of Campylobacter. As measured on boot socks, Campylobacter was more prevalent in livestock-dominated North West than in East Anglia (55.8% of socks, vs 38.6%). Campylobacter peaked during winter in both regions, and peaked again in spring in North West. Precipitation was associated with greater Campylobacter, and higher temperatures with less. The results "are consistent with our understanding of Campylobacter survival and the probability of material adhering to boot socks," according to the report. C. jejuni was the most commonly found species, with C. coli largely restricted to the livestock dominated North West, according to the report. Source attribution analysis suggested that the major source of C. jejuni was sheep in North West, and wild birds in East Anglia. The motivation for the study was the desire to develop an efficient sampling method to explore the potential for transfer of Campylobacter from the environment to humans through visits to the countryside, and to determine whether any such risk varied seasonally, said Jones. Campylobacter is the most common bacterial cause of diarrheal disease in the developed world. "It is known that food is often a source of Campylobacter infections in humans, but we also know that exposure through food cannot explain all the cases seen in the human population," said Jones. "Exploring other potential routes was a key motivation." Conventional sampling is based on sampling from a single point, called spot sampling, and does not sample human-pathogen interactions. "Ultimately, this research could lead to interventions to reduce the risk to humans," said Jones. Explore further: The need to feed programs Campylobacter's 'Sat Nav'


News Article | April 28, 2017
Site: www.eurekalert.org

Washington, DC - April 28, 2017 - Yersinia pestis, the bacterium that causes bubonic plague, can survive within the ubiquitous soil protozoan, the amoeba, by producing proteins that protect against the latter microbe's digestion. The research is published April 28th in Applied and Environmental Microbiology, a journal of the American Society for Microbiology. The research is important because plague is a re-emerging disease, according to the Centers for Disease Control and Prevention, with 95 percent of cases occurring in sub-Saharan Africa and Madagascar. Modern antibiotics are effective, but without prompt treatment, plague can cause serious illness, or death. Y. pestis spreads from rodent to rodent, and sometimes to human, often via fleas It uses the protective niche of the amoeba to abide when conditions are unfavorable to its spread, that is, when rodents are scarce, said Viveka Vadyvaloo, PhD, Assistant Professor, Paul G. Allen School for Global Animal Health, Washington State University, Pullman. Amoebae are similar to certain human immune cells, the macrophages, in their ability to engulf bacteria, or other nourishing items of similar size.These are taken up within special compartments called vacuoles, which in both amoebae and humans are capable of digestion. (image: scanning electron micrograph of a mass of Yersinia pestis.) "With this in mind, graduate student Javier Benavides-Montaño separately cultured three distinct Y. pestis strains that have been associated with human epidemics, with a common laboratory strain of the free-living soil amoeba, Acanthamoeba castellanii, in a medium that supports the latter's growth," said Vadyvaloo. Benavides-Montaño then tested Y. pestis' ability to enter and survive within the amoeba. To do so, he killed any bacteria that were outside of the amoebae, and then gently lysed the latter, and then placed the lysed content on a medium that encourages Y. pestis to grow. They were able to culture Y. pestis only after the amoebae had been lysed. The investigators also used electron microscopy to peer inside intact amoebae, and found Y. pestis within the vacuoles. "To understand more about how Y. pestis might be surviving within amoebae we considered how Y. pestis survive in human macrophages," said Vadyvaloo. "Macrophages usually engulf bacterial pathogens and destroy them, but some bacterial pathogens are able to avoid being killed therein by producing proteins that block the digestion." Indeed, that is the key strategy for a number of human pathogens. Some such proteins are known. So the investigators used mutant Y. pestis that doesn't produce one of these proteins. Those mutants failed to survive within the amoebae. Vadyvaloo said that amoebae's longstanding reputation as Trojan horses for human pathogens led her to investigate the possibility that plague bacteria could abide within their vacuoles. The best known example of this phenomenon had been Legionnaires' Disease, a respiratory disease that was discovered in 1976 after an outbreak among attendees at a convention of the American Legion in Philadelphia. "This study serves as a proof of principle that amoebae can support prolonged survival of Y. pestis in the environment," said Vadyvaloo. It may encourage a search for this interaction within areas of Colorado and New Mexico where plague is endemic. And that, she said, could enable prediction of potential disease re-emergence, thereby reducing spread to humans. The American Society for Microbiology is the largest single life science society, composed of over 48,000 scientists and health professionals. ASM's mission is to promote and advance the microbial sciences. ASM advances the microbial sciences through conferences, publications, certifications and educational opportunities. It enhances laboratory capacity around the globe through training and resources. It provides a network for scientists in academia, industry and clinical settings. Additionally, ASM promotes a deeper understanding of the microbial sciences to diverse audiences.


One reason that drinking water and public swimming pools are treated with chlorine is to kill such disease-causing organisms. Chlorine successfully eliminates a number of harmful pathogens—but not all of them. Cryptosporidium parvum is one such chlorine-resistant pathogen. A protozoan parasite that is transmitted through either direct contact or ingestion of contaminated food or water, C. parvum is found in animal and human fecal matter. According to the Centers for Disease Control and Prevention, C. parvum is a leading cause of waterborne disease among humans in the United States. Infection can lead to cryptosporidiosis which, in healthy people, causes severe diarrheal disease that can last for weeks. For the elderly, infants, or the immunocompromised, the infection can be deadly. Because contaminated drinking water has been linked to major outbreaks of cryptosporidiosis, detecting and removing C. parvum in source waters is very important to protecting public health. Now two Lehigh University engineers are investigating how C. parvum oocysts— the development stage in which the parasite exists in the environment—attach to environmental biofilms, which are the microbial communities that grow on underwater surfaces, like rocks. Their ultimate goal is the development of an improved detection method that can identify a contamination source quicker and more cheaply than current methods, preventing widespread infection. "We think we can develop a surface that can be commercially produced for around $5," says Kristen L. Jellison, associate professor of civil and environmental engineering. "This would allow utilities and water resource managers to better protect the public from exposure by sampling more locations with greater frequency and obtaining more reliable and comprehensive data about the sources of the parasite in the watershed." Jellison and her Lehigh colleague Sabrina S. Jedlicka, associate professor of materials science and engineering, are the first to demonstrate that the attachment of oocysts to environmental biofilms is a calcium-mediated process—a crucial step toward their goal. Jellison and Jedlicka describe their results in an article in Applied and Environmental Microbiology called: "Pseudo-second-order calcium-mediated Cryptosporidium parvum oocyst attachment to environmental biofilms." Understanding the mechanism that enables oocysts to attach to biofilms is important for calculating the attachment efficiency, or the rate at which the parasite binds to the material. Understanding the rate is key for two reasons: One, it may enable calculation of oocyst concentration in the water based on numbers of oocysts attached to a material; and, two, it is needed to design materials that maximize oocyst attachment. Such attachment-enabling material will make it possible to detect the source of the infestation faster and more inexpensively than current methods allow. "The number of oocysts on a given biofilm sample reveal how much of the parasite is present in the water," explains Jellison. "For example—simply for illustration's sake - say that five oocysts attach to a biofilm downstream of the contamination source. That may indicate the presence of 100 oocysts further upstream. If we see ten oocysts attaching, it might mean there are 200 at the main source." Jellison's and Jedlicka's study provides new insights into the impact of calcium on the attachment of C. parvum oocysts to environmental biofilms. In addition, their modeling method could be used to elucidate the behavior of oocysts in commonly encountered complex aquatic systems—an important step in enabling future innovations in parasite detection and treatment technologies to protect public health. The idea for using environmental biofilms to identify a C. parvum contamination source first occurred to Jellison during her work with the Philadelphia Water Department on the detection of Cryptosporidium in the Wissahickon and Schuykill watersheds. The EPA-approved filtration-based methods used to test the water sources were expensive and the results were inconsistent. According to Jellison, one filter could cost as much as $120.00. That may not sound like a large sum, but considering the limited resources of many municipal water departments—and the number of filters that might be needed to accurately detect the source of a C. parvum contamination—it represents a serious obstacle. "Recovery using current methods depends on variables such as the cleanliness of water and the skill of the person doing the testing," says Jellison. "C. parvum can be present in the water in very small amounts. You can check a 10 Liter sample and not detect the parasite. But it could be present in the water." In her work testing the watersheds near Philadelphia, Jellison would scrape biofilms off of rocks both upstream and downstream of a suspected C. parvum contamination location and then test the samples in her lab at Lehigh. Over time, the biofilm samples provided comparable data to the approved filtration method - but at much lower cost. "Being able to test the water accurately and in more places increases the likelihood of identifying the contamination source and decreases the chance that thousands of people will become infected," says Jellison. Jellison's downstream biofilm samples contained more oocysts than the samples taken from rocks upstream of suspected point sources. However, there was no way to identify when the oocysts attached. The clues provided by the biofilms were important for confirming that C. parvum was entering the water at particular locations, but not much help in revealing when the contamination events occurred. If Jellison could figure out when, precisely, the oocysts attached, she would be better able to identify patterns of oocyst contamination which would enable more effective source water protection strategies. That is where Jedlicka comes in. Jedlicka—a materials scientist who says she "comes from a field of designing surfaces to illicit behavior in cells"—does the mathematical modeling that enables the duo to calculate the attachment efficiency of C. parvum to biofilms. "We need an understanding of the chemistry behind the binding process to know what designs will work best," says Jedlicka. Jedlicka's ability to calculate the binding force is what led to the demonstration of a calcium-mediated binding process. "When we took the calcium out, the binding efficiency went down significantly, which is one way we knew that calcium is important to binding," says Jedlicka. In addition to contributing to improved detection methods, creating a surface design that maximizes the attachment of oocysts has other implications as well. "If we can identify the binding mechanism that enables C. parvum to 'stick' to biofilms, we can create an improved means to remove it," says Jellison. "Understanding the mechanism could even open the door to preventing the parasite from binding in the intestine and making people sick." Among the team's next steps is investigating the other chemical processes involved in the binding, in addition to calcium. They also plan to test their model under a number of conditions, including hydrodynamic sheer stresses. "If we can help utilities find a way to monitor multiple points in the watershed instead of just a few, they can put their limited resources to more effective use," says Jellison. "Until then," says Jedlicka, "we'll just keep asking ridiculously hard science questions." More information: Xia Luo et al, Pseudo-second-order calcium-mediatedoocyst attachment to environmental biofilms, Applied and Environmental Microbiology (2016). DOI: 10.1128/AEM.02339-16


News Article | December 13, 2016
Site: www.rdmag.com

The life of a watershed is complex. The watershed is the area of land separating the smaller water flows that feed into a larger, common outlet--like a river, lake or ocean. As such, it is often home to a variety of wildlife, as well as subject to agricultural and recreational uses. From this complicated ecosystem, bacteria, viruses and parasites emerge--sometimes making their way into the water supply. One reason that drinking water and public swimming pools are treated with chlorine is to kill such disease-causing organisms. Chlorine successfully eliminates a number of harmful pathogens--but not all of them. Cryptosporidium parvum is one such chlorine-resistant pathogen. A protozoan parasite that is transmitted through either direct contact or ingestion of contaminated food or water, C. parvum is found in animal and human fecal matter. According to the Centers for Disease Control and Prevention, C. parvum is a leading cause of waterborne disease among humans in the United States. Infection can lead to cryptosporidiosis which, in healthy people, causes severe diarrheal disease that can last for weeks. For the elderly, infants, or the immunocompromised, the infection can be deadly. Because contaminated drinking water has been linked to major outbreaks of cryptosporidiosis, detecting and removing C. parvum in source waters is very important to protecting public health. Now two Lehigh University engineers are investigating how C. parvum oocysts-- the development stage in which the parasite exists in the environment--attach to environmental biofilms, which are the microbial communities that grow on underwater surfaces, like rocks. Their ultimate goal is the development of an improved detection method that can identify a contamination source quicker and more cheaply than current methods, preventing widespread infection. "We think we can develop a surface that can be commercially produced for around $5," says Kristen L. Jellison, associate professor of civil and environmental engineering. "This would allow utilities and water resource managers to better protect the public from exposure by sampling more locations with greater frequency and obtaining more reliable and comprehensive data about the sources of the parasite in the watershed." Jellison and her Lehigh colleague Sabrina S. Jedlicka, associate professor of materials science and engineering, are the first to demonstrate that the attachment of oocysts to environmental biofilms is a calcium-mediated process--a crucial step toward their goal. Jellison and Jedlicka describe their results in an article in Applied and Environmental Microbiology called: "Pseudo-second-order calcium-mediated Cryptosporidium parvum oocyst attachment to environmental biofilms." Understanding the mechanism that enables oocysts to attach to biofilms is important for calculating the attachment efficiency, or the rate at which the parasite binds to the material. Understanding the rate is key for two reasons: One, it may enable calculation of oocyst concentration in the water based on numbers of oocysts attached to a material; and, two, it is needed to design materials that maximize oocyst attachment. Such attachment-enabling material will make it possible to detect the source of the infestation faster and more inexpensively than current methods allow. "The number of oocysts on a given biofilm sample reveal how much of the parasite is present in the water," explains Jellison. "For example--simply for illustration's sake - say that five oocysts attach to a biofilm downstream of the contamination source. That may indicate the presence of 100 oocysts further upstream. If we see ten oocysts attaching, it might mean there are 200 at the main source." Jellison's and Jedlicka's study provides new insights into the impact of calcium on the attachment of C. parvum oocysts to environmental biofilms. In addition, their modeling method could be used to elucidate the behavior of oocysts in commonly encountered complex aquatic systems--an important step in enabling future innovations in parasite detection and treatment technologies to protect public health. The idea for using environmental biofilms to identify a C. parvum contamination source first occurred to Jellison during her work with the Philadelphia Water Department on the detection of Cryptosporidium in the Wissahickon and Schuykill watersheds. The EPA-approved filtration-based methods used to test the water sources were expensive and the results were inconsistent. According to Jellison, one filter could cost as much as $120.00. That may not sound like a large sum, but considering the limited resources of many municipal water departments--and the number of filters that might be needed to accurately detect the source of a C. parvum contamination--it represents a serious obstacle. "Recovery using current methods depends on variables such as the cleanliness of water and the skill of the person doing the testing," says Jellison. "C. parvum can be present in the water in very small amounts. You can check a 10 Liter sample and not detect the parasite. But it could be present in the water." In her work testing the watersheds near Philadelphia, Jellison would scrape biofilms off of rocks both upstream and downstream of a suspected C. parvum contamination location and then test the samples in her lab at Lehigh. Over time, the biofilm samples provided comparable data to the approved filtration method - but at much lower cost. "Being able to test the water accurately and in more places increases the likelihood of identifying the contamination source and decreases the chance that thousands of people will become infected," says Jellison. Jellison's downstream biofilm samples contained more oocysts than the samples taken from rocks upstream of suspected point sources. However, there was no way to identify when the oocysts attached. The clues provided by the biofilms were important for confirming that C. parvum was entering the water at particular locations, but not much help in revealing when the contamination events occurred. If Jellison could figure out when, precisely, the oocysts attached, she would be better able to identify patterns of oocyst contamination which would enable more effective source water protection strategies. That is where Jedlicka comes in. Jedlicka--a materials scientist who says she "comes from a field of designing surfaces to illicit behavior in cells"--does the mathematical modeling that enables the duo to calculate the attachment efficiency of C. parvum to biofilms. "We need an understanding of the chemistry behind the binding process to know what designs will work best," says Jedlicka. Jedlicka's ability to calculate the binding force is what led to the demonstration of a calcium-mediated binding process. "When we took the calcium out, the binding efficiency went down significantly, which is one way we knew that calcium is important to binding," says Jedlicka. In addition to contributing to improved detection methods, creating a surface design that maximizes the attachment of oocysts has other implications as well. "If we can identify the binding mechanism that enables C. parvum to 'stick' to biofilms, we can create an improved means to remove it," says Jellison. "Understanding the mechanism could even open the door to preventing the parasite from binding in the intestine and making people sick." Among the team's next steps is investigating the other chemical processes involved in the binding, in addition to calcium. They also plan to test their model under a number of conditions, including hydrodynamic sheer stresses. "If we can help utilities find a way to monitor multiple points in the watershed instead of just a few, they can put their limited resources to more effective use," says Jellison. "Until then," says Jedlicka, "we'll just keep asking ridiculously hard science questions."


News Article | February 24, 2017
Site: www.eurekalert.org

Washington, DC - February 24, 2017 - Many recent reports have found multidrug resistant bacteria living in hospital sink drainpipes, putting them in close proximity to vulnerable patients. But how the bacteria find their way out of the drains, and into patients has been unclear. Now a team from the University of Virginia, Charlottesville, has charted their pathways. The research is published February 24 in Applied and Environmental Microbiology, a journal of the American Society for Microbiology. "Our study demonstrates that bacterial spread from drainpipes to patients occurs via a staged mode of transmission," said principal investigator Amy Mathers, MD, Associate Professor of Medicine and Pathology, Division of Infectious Diseases and International Health. Initially, the bacteria colonize the elbows of the drain pipes. The investigators showed that from there, the colonies grow slowly towards the sink strainers--at the rate of roughly one inch per day, said Mathers. Given the distance in typical hospital sinks of elbows below the sink bowls, it frequently takes a week for the colonies to reach the sink strainers. From there, bacteria quickly get splattered around the sink, and even onto the counters surrounding the sinks, where they can be picked up by the patients. The project grew out of the knowledge that patients are dying from infections with multidrug resistant bacteria that they acquire while hospitalized. In a review Mathers' team conducted with Alice Kizny Gordon, MBBS (a degree that is common in UK and is like MD) and colleagues of the University of Oxford, UK, they found more than 32 papers describing the spread of bacteria resistant to carbapenem--an important antibiotic--via sinks, and other reservoirs of water within hospitals. Half of those papers have appeared since 2010. In many parts of the world, hospitals are ill-equipped to cope with these superbugs, as in many cases there are few treatment options, said Mathers. "We wanted to better understand how transmission occurs, so that the numbers of these infections could be reduced," she said. The work entailed building what Mathers said is "the only sink lab we are aware of in the US." The lab contains five identical sinks, modeled after the most common ICU sink in the University of Virginia's hospital in Charlottesville. The experimental bacteria are Escherichia coli, which commonly harmlessly inhabit the human intestinal tract. They can acquire both pathological genes, and antibiotic resistance genes, and become superbugs. Mathers et al. are now using the sink lab to conduct a follow-up study, in collaboration with the Centers for Disease Control and Prevention. The goal is to determine precisely how the pathogens reach the patients, said Mathers. "This type of foundational research is needed to understand how these bacteria are transmitted so that we can develop and test potential intervention strategies that can be used to prevent further spread. The American Society for Microbiology is the largest single life science society, composed of over 48,000 scientists and health professionals. ASM's mission is to promote and advance the microbial sciences. ASM advances the microbial sciences through conferences, publications, certifications and educational opportunities. It enhances laboratory capacity around the globe through training and resources. It provides a network for scientists in academia, industry and clinical settings. Additionally, ASM promotes a deeper understanding of the microbial sciences to diverse audiences.


News Article | March 1, 2017
Site: news.yahoo.com

Drug-resistant bacteria can lurk in the pipes of hospital sinks, and a new study shows that these dangerous bacteria can also make their way out of sinks and continue on to reach patients. A number of recent reports have found that drug-resistant bacteria grow in the drainpipes of hospital sinks, according to the study, published today (Feb. 24) in the journal Applied and Environmental Microbiology. "The wet, humid and relatively protected environment" of the drainpipes makes for an ideal breeding ground for bacteria, the researchers wrote. In addition, many reports have also found a genetic link between the pathogens in hospital drainpipes and the pathogens in patients, they wrote. In other words, the same bacteria found in the drainpipes have been found in infected patients. [6 Superbugs to Watch Out For] But it was unclear how these pipe-dwelling bacteria ended up infecting patients, considering patients don't come into direct contact with the insides of drainpipes. To trace the path from pipe to patient, the researchers built a lab with five identical hospital sinks that were all connected via plumbing. It was "the only sink lab we are aware of in the U.S.," senior study author Dr. Amy Mathers, an associate professor of medicine and pathology at the University of Virginia School of Medicine, said in a statement. The researchers began by colonizing the elbow of the drainpipe — also called the P-trap — in one of the sinks with Escherichia coli bacteria. For the first two weeks of the experiment, the researchers occasionally ran water from the faucet, and they did not observe much bacterial growth. But after two weeks, they stopped turning on the faucet, and instead added nutrients to the drainpipe, based on what they predicted would be found in a hospital, such as intravenous fluid, feeding supplements and leftover beverages. The nutrients jolted the E. coli into action: The researchers observed that the nutrient-fed bacteria colony grew at an average rate of 1 inch (2.5 centimeters) a day, reaching the sink strainer after just one week. And the bacteria didn't only grow upward, toward the sink; they also grew along the pipes that connected the five sinks. (The sinks in the researchers' lab were all in a row.) Seven days after the E. coli in a sink at the end of the rowwas given nutrients, the researchers found bacteria in the pipes of the next three sinks in the row. Only the sink on the opposite end of the row didn't have bacteria in the pipe. Moreover, one week after that, the bacteria had grown up to the sink strainer in two more sinks, they found. But the question of how the bacteria could reach a patient still remained. [Tiny & Nasty: Images of Things That Make Us Sick] To see how the bacteria spread further, the researchers placed a number of petri dishes in areas around the sink — including the countertop, the sink bowl, the faucet and the faucet handles — and ran the water. They found that running the faucet when there was E. coli in the sink strainer caused the bacteria to be dispersed to petri dishes up to 30 inches (76 cm) away. In other words, the bacteria are splattered around the sink, and can be picked up by hospital workers or patients. In the dispersion experiment, the researchers noted that the highest concentrations of bacteria were found closer to the faucet, which may be due to the specific design of the sink bowl and the faucet used in the study. This is important, as many hospital sinks have similar designs, the researchers wrote. An understanding of how the bacteria are spread is important, Mathers said, as it gives researchers the opportunity to "develop and test potential intervention strategies that can be used to prevent further spread."


News Article | March 2, 2017
Site: www.chromatographytechniques.com

Researchers from the University of Leicester have for the first time discovered that bacteria that cause respiratory infections are directly affected by air pollution - increasing the potential for infection and changing the effectiveness of antibiotic treatment. The interdisciplinary study, which has been published in the journal Environmental Microbiology, has important implications for the treatment of infectious diseases, which are known to be increased in areas with high levels of air pollution. The study looked into how air pollution affects the bacteria living in our bodies, specifically the respiratory tract - the nose, throat and lungs. A major component of air pollution is black carbon, which is produced through the burning of fossil fuels such as diesel, biofuels, and biomass. The research shows that this pollutant changes the way in which bacteria grow and form communities, which could affect how they survive on the lining of our respiratory tracts and how well they are able to hide from, and combat, our immune systems. "This work increases our understanding of how air pollution affects human health. It shows that the bacteria which cause respiratory infections are affected by air pollution, possibly increasing the risk of infection and the effectiveness of antibiotic treatment of these illnesses," said Julie Morrissey, associate professor in Microbial Genetics in the University of Leicester's Department of Genetics and lead author on the paper. "Our research could initiate an entirely new understanding of how air pollution affects human health. It will lead to enhancement of research to understand how air pollution leads to severe respiratory problems and perturbs the environmental cycles essential for life." "Everybody worldwide is exposed to air pollution every time they breathe. It is something we cannot limit our exposure to as individuals, but we know that it can make us ill. So we need to understand what it is doing to us, how it is making us unhealthy, and how we might be able to stop these effects," said Shane Hussey and Jo Purves, the research associates working on the project. The research focused on two human pathogens, Staphylococcus aureus and Streptococcus pneumoniae, which are both major causes of respiratory diseases and exhibit high levels of resistance to antibiotics. The research team found that black carbon alters the antibiotic tolerance of Staphylococcus aureus communities and importantly increases the resistance of communities of Streptococcus pneumoniae to penicillin, the front line treatment of bacterial pneumonia. Furthermore, it was found that black carbon caused Streptococcus pneumoniae to spread from the nose to the lower respiratory tract, which is a key step in development of disease. "Urbanization in megacities with extreme levels of air pollution are major risk factors for human health in many parts of the world. Our research seeks to lead and participate in international research consortia of biologists, chemists, clinician, social scientists and urban planners. Together we will investigate how increasing urbanization promotes infectious disease," said Julian Ketley, professor of Bacterial Genetics, Department of Genetics and Peter Andrew, Professor of Microbial Pathogenesis, Department of Infection, Immunity and Inflammation. The World Health Organization describes air pollution as the "largest single environmental health risk." Air pollution is thought to be responsible for at least 7 million deaths per year, which equates to an eighth of all global deaths. The UK and many other countries around the world continue to breach the recommended pollution limits set by the World Health Organization.


News Article | March 2, 2017
Site: www.eurekalert.org

Interdisciplinary research at the University of Leicester has explored the impact of black carbon on bacteria in the respiratory tract "Our research could initiate an entirely new understanding of how air pollution affects human health. It will lead to enhancement of research to understand how air pollution leads to severe respiratory problems and perturbs the environmental cycles essential for life" - Dr Julie Morrissey, University of Leicester Image of Streptococcus pneumoniae with black carbon available here: https:/ Researchers from the University of Leicester have for the first time discovered that bacteria that cause respiratory infections are directly affected by air pollution - increasing the potential for infection and changing the effectiveness of antibiotic treatment. The interdisciplinary study, which has been published in the journal Environmental Microbiology, has important implications for the treatment of infectious diseases, which are known to be increased in areas with high levels of air pollution. The study looked into how air pollution affects the bacteria living in our bodies, specifically the respiratory tract - the nose, throat and lungs. A major component of air pollution is black carbon, which is produced through the burning of fossil fuels such as diesel, biofuels, and biomass. The research shows that this pollutant changes the way in which bacteria grow and form communities, which could affect how they survive on the lining of our respiratory tracts and how well they are able to hide from, and combat, our immune systems. Dr Julie Morrissey, Associate Professor in Microbial Genetics in the University of Leicester's Department of Genetics and lead author on the paper, said: "This work increases our understanding of how air pollution affects human health. It shows that the bacteria which cause respiratory infections are affected by air pollution, possibly increasing the risk of infection and the effectiveness of antibiotic treatment of these illnesses. "Our research could initiate an entirely new understanding of how air pollution affects human health. It will lead to enhancement of research to understand how air pollution leads to severe respiratory problems and perturbs the environmental cycles essential for life." Dr Shane Hussey and Dr Jo Purves, the research associates working on the project said: "Everybody worldwide is exposed to air pollution every time they breathe. It is something we cannot limit our exposure to as individuals, but we know that it can make us ill. So we need to understand what it is doing to us, how it is making us unhealthy, and how we might be able to stop these effects." The research focused on two human pathogens, Staphylococcus aureus and Streptococcus pneumoniae, which are both major causes of respiratory diseases and exhibit high levels of resistance to antibiotics. The research team found that black carbon alters the antibiotic tolerance of Staphylococcus aureus communities and importantly increases the resistance of communities of Streptococcus pneumoniae to penicillin, the front line treatment of bacterial pneumonia. Furthermore, it was found that black carbon caused Streptococcus pneumoniae to spread from the nose to the lower respiratory tract, which is a key step in development of disease. Professors Julian Ketley, Professor of Bacterial Genetics, Department of Genetics and Peter Andrew, Professor of Microbial Pathogenesis, Department of Infection, Immunity and Inflammation, said: "Urbanisation in megacities with extreme levels of air pollution are major risk factors for human health in many parts of the world. Our research seeks to lead and participate in international research consortia of biologists, chemists, clinician, social scientists and urban planners. Together we will investigate how increasing urbanisation promotes infectious disease." The World Health Organization describes air pollution as the "largest single environmental health risk". Air pollution is thought to be responsible for at least 7 million deaths per year, which equates to an eighth of all global deaths. The UK and many other countries around the world continue to breach the recommended pollution limits set by the World Health Organization. Professor Paul Monks, Pro-Vice-Chancellor and Head of the College of Science and Engineering, who is a leading expert on air pollution added: "The lead investigators have brought together their expertise in genetics, microbiology and air pollution chemistry to provide truly multidisciplinary ground breaking insights. "This research has significant potential to initiate a global research effort to understand a hitherto unknown effect of air pollution and provide significant additional impetus to the control of pollution." The four year study was conducted by a University of Leicester's College of Medicine, Biological Sciences and Psychology PhD studentship, and research grants from The Leverhulme Trust and the Natural Environment Research Council (NERC). The study published in Environmental Microbiology is available here: http://onlinelibrary.


News Article | February 15, 2017
Site: www.eurekalert.org

Washington, DC - Feb. 10, 2017 - Lecithin, a natural emulsifier commonly used in processed foods, synergistically enhances the antimicrobial properties of the natural essential oil, eugenol, but only when applied in very small quantities. The research is published in Applied and Environmental Microbiology, a journal of the American Society for Microbiology. "This is the first time that lecithin has been shown to exhibit synergism in combination with a bioactive compound at a critical concentration," said corresponding author Federico M. Harte, PhD, associate professor of food science, Pennsylvania State University, State College, PA. The research began serendipitously. Lecithin had been known to improve the physical stability of essential oils in aqueous systems, including eugenol, which is derived from clove. "Our initial goal was to reduce the droplet size of eugenol using high pressure homogenization," said Harte. The purpose of shrinking the droplet size was to put each bacterium in contact with as many tiny eugenol droplets as possible. "In order to increase the antimicrobial power of eugenol, we thought it was better to have huge numbers of nanoscale droplets in contact with one bacterium than to have a single milliliter diameter droplet with only one point of contact with a bacterium," said Harte. When they failed to squeeze the droplets down to less than 100 nm, "we decided to add a small amount of lecithin with the hope of creating even smaller eugenol droplets," said Harte. (Emulsifiers reduce the size of droplets in target liquids.) At this point, the investigation seemed to go awry. Holding that size constant, they obtained antimicrobial activity that varied unpredictably, "suggesting high experimental error," said Harte. From there, the investigators proceeded, keeping the eugenol content constant, while assaying different tiny amounts of lecithin, said Harte. These experiments demonstrated that at a critical concentration, lecithin synergistically increased eugenol's antimicrobial properties. The most obvious benefit from the research would be to use lecithin to boost the antimicrobial properties of natural components in foods, said Harte. More generally, "Our research shows that lecithin has bioactive properties that we have ignored until now. What are the consequences in terms of specific benefits or hazards for human beings is difficult to predict at this point." Harte plans to investigate the potential of lecithin to alter the permeability of mammalian cells, research that he emphasizes is fairly basic, but which could ultimately lead to biomedical applications. One very interesting possibility would be to change the permeability of the blood brain barrier, in order to enable passage of insoluble drugs. "But it's way too soon to make predictions," said Harte. The American Society for Microbiology is the largest single life science society, composed of over 48,000 scientists and health professionals. ASM's mission is to promote and advance the microbial sciences. ASM advances the microbial sciences through conferences, publications, certifications and educational opportunities. It enhances laboratory capacity around the globe through training and resources. It provides a network for scientists in academia, industry and clinical settings. Additionally, ASM promotes a deeper understanding of the microbial sciences to diverse audiences.

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