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Silver-coated Endotracheal Tube Dramatically Reduces Resistant Infections
ScienceDaily (May 21, 2008) — A silver-coated endotracheal tube may reduce infections with highly resistant bacteria over traditional tubes by nearly half, according to the results of a large randomized trial to be presented at the American Thoracic Society's 2008 International Conference in Toronto on May 19.
Patients who are on ventilators are often at risk for developing ventilator-associated pneumonia (VAP) because of resistant bacteria.
"VAP is a serious disease with significant mortality," said lead investigator, Andrew Shorr, M.D., M.P.H., of Washington Hospital Center in Washington, D.C. "Crude mortality rates from VAP approach 25 to 30 percent and VAP rates are now thought to reflect hospital quality. These infections include highly resistant pathogens, such as methicillin-resistant Staphylococcus aureus or MRSA, which are the most troubling ones and often the hardest to treat. The average costs associated with treatment of VAP exceed $40,000 because of the impact on length of stay in the ICU."
To test the efficacy of the silver-coated tube in preventing infections, the study included a modified intention-to-treat population of 1,509 subjects, balanced between traditional endotracheal tubes and the silver coated ones. The researchers used brochoavelolar lavage fluid cultures to ascertain the presence of pathogenic organisms and classified as "highly resistant" organisms MRSA, Pseudomonas aeruginosa (PA) and Acinetobacter bumanii (AB).
They found that VAP in all its forms was reduced by nearly 40 percent in the population with the silver-coated endotracheal tubes and that highly resistant infections were less than half as likely to occur in those with the silver-coated tubes.
"What we show in this present analysis is that the silver-coated breathing tube prevents infections due to the most highly resistant pathogens. Other prevention strategies for VAP have not always been shown to impact the rates of infection with these highly resistant strains," said Dr. Shorr. "Given the importance of MRSA, PA and AB in the ICU, utilization of the silver-coated endotracheal tube may help contain the spread of antimicrobial resistance."
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http://www.sciencedaily.com/releases/2008/05/080519133449.htm
Sunlight (ultraviolet light).
Old Fashioned Soap. Forget the 'gels' that have been linked to durable infections and lack of cleanliness in the hospital environment.
Both found to be very effective in cutting down biological infections without the capacities of just breeding better 'superbugs' that attack the human system later biologically.
Bacteria-Killing Bandage
Biochemists Create Microbicidal Coating to Fight Hospital Infections
March 1, 2006 — New bandages with microbicidal coating kill the most harmful bacteria on contact. The coating is washable and can also be used on hospital gowns and bed sheets, which will help reduce the risk of infection to all hospital patients and staff. Up to 20,000 Americans get hospital infections every year
GAINESVILLE, Fla.--You go there for help, but millions of Americans get sick in hospitals. Hospital infections are growing to epidemic proportions because they're passed from person to person. Now, researchers are working to wipe out these infections with a new bacteria-killing bandage.
Gary Smithson was hit head-on by a drunk driver. The accident put him in a wheelchair, but that is not what keeps him there. It's what happened in the ER -- hours after the crash -- that has made the past 10 years unbearable. During a routine check, doctors found an infection.
Gary is one of 20,000 Americans that leave the hospital each year with an infection they didn't come in with. Gregory Schultz, a biochemist at the University of Florida in Gainesville, is part of a team working to wipe out these super bugs. They've created a microbicidal coating that can kill the most harmful bacteria.
"The microbicidal agent -- that's the thing that kills the bacteria -- is permanently bonded on the surface of the fibers of the dressing," Schultz says.
The bandage on the left is not treated with the microbicidal coating. The area in red is infected with bacteria. Now, look at the bandage on the right. It is treated -- you can see there are no bacteria.
Chris Batich, a biomaterials expert at the University of Florida, says, "What we wound up with is a surface that you can wash. And whenever it touches bacteria, it kills the bacteria ... and keeps on killing them."
The microbicidal coating can also be used on hospital gowns and bed sheets, which will help reduce the risk of infection to all hospital patients and staff.
Because of his infection, Gary believes he will spend the rest of his life in wheelchairs he fixes in his shop. "It's completely changed the way I have to live," he says. Every day is a struggle against an invisible invader that Gary hopes won't claim any more innocent victims.
The bacteria-fighting agent can be used outside the hospital for soldiers in the field to help stop athletes foot. The cost of putting this agent on a bandage is about one cent.
---
http://www.sciencedaily.com/videos/2006/0304-bacteriakilling_bandage.htm
Beetles Are Inspiration For New Antibacterial Coatings
Materials Scientists Copy Beetle Anatomy To Develop New Coatings
March 1, 2007 — Scientists at M.I.T. looking to add new chemical functionalities to spray coatings have turned to the beetle for inspiration. Some beetles that live in very arid climates get their drinking water by trapping water droplets from fog.
The droplets collect on a bumpy surface on their backs and once they become big enough, the water drops slide down a smooth surface into their mouths. These dueling surfaces are being mimicked by scientists in order to create antibacterial coatings.
When you think of a beetle, you think creepy, crawly critters. Now add one more adjective to the list: Clever -- clever because despite living in the desert, the beetle is able to gather drinking water.
"The beetle is able to gather, out of this very light fog, enough water to survive -- to take a drink every morning and survive to live another day," Robert Cohen, a chemical engineer at MIT in Cambridge, tells DBIS.
The Namib Desert beetle has dueling surfaces on its back. The smooth parts repel water, while the top bumpy parts collect water.
MIT materials scientist Michael Rubner says that pattern motif creates this incredible ability to gather and harvest small drops of water from the fog. As fog rolls in, the bumps on its back trap water. As the droplets get bigger, the water then rolls down into the beetle's mouth.
Scientists are trying to mimic this idea by dipping glass into solutions of charged polymers, imitating the porous and smooth coating of the beetle. The material is then coated with a Teflon-like substance, making it water-repellent.
Their next step is to add an antibacterial agent [perhaps silver] into the coating that may be used on common hospital, kitchen and bathroom surfaces to stop germs from spreading. If all goes well, the beetle could possibly stop germs in their tracks.
"What we're very interested now is the possibility of adding more chemical functionality to what the beetle has taught us," Rubner says.
There is also promise of creating larger-scale pieces of water-repellent material that could be used to collect water in arid climates. The scientists say the key is creating dueling surfaces in areas where water is present, but hard to collect.
BACKGROUND: Inspired by the Namib Desert beetle that lives in one of the driest regions of the world, researchers at the Massachusetts Institute of Technology, in Cambridge, have developed a new material that can capture and control tiny amounts of water, just like the beetle does. Applications include its use for self-contaminating surfaces that could channel and collect harmful substances, such as germs, that could then be easily killed or deactivated. It could also be used for lab-on-a-chip diagnostics of DNA screening.
ABOUT DESERT BEETLES: The desert beetle has a built-in water collection system that allows it to survive where there is no water to be found, even when the humidity in the air is close to zero. This is important since normal condensation can't take place in the Namib Desert because the fog is too light. When fog blows across the surface of the beetle's back, water droplets begin to gather on top of the bumps on the insect's back These bumps attract water. They are also surrounded by waxy, water-repellent channels that pins the water drops on the beetle's back. Over time, the droplets get bigger, until they are large enough to roll down into the insect's mouth.
ABOUT THE MATERIAL: The new material developed by the MIT scientists can capture and control tiny amounts of water because its structure mimics that of the desert beetle. There are two surfaces, one water-repellant and another water attracting, that act together to separate and channel water drops. The researchers found they could control the surface texture of their material by repeatedly dipping glass or plastic substrates into charged polymer solutions. With every dip, another layer coats the surface, gradually making the material more porous so it easily attracts water. Adding silica nanoparticles -- particles only a few millions of a millimeter wide -- creates even more bumps to trap the collected water droplets. The final touch is a Teflon-like coating that makes the material super-water-repellent. And the scientists can create any pattern they want by adding more layers of charged polymers or nanoparticles in specific areas.
The Materials Research Society contributed to the information contained in the video portion of this report.
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http://www.sciencedaily.com/videos/2007/0307-beetles_are_inspiration_for_new_antibacterial_coatings.htm
[in the above article, nano is deadly. stop using it. it should be banned. see the building materials category for its list of dangers.]
Microbiologists Find Soap and Water Best for Washing Hands, Removing Germs
December 1, 2005 — Microbiologists tested 14 hand-hygiene agents -- everything from soap and alcohol rubs to plain old tap water -- against hardy bacteria and viruses applied to the hands of 62 volunteers. The study found that soap and water did the best job of removing germs.
Just 10 seconds of washing soap and water was enough to knock off more than 90 percent of microbes.
CHAPEL HILL--Cold and flu season is fast approaching and before you start sniffling and sneezing, you should know the number one way scientists say to fight germs before they become a full-blown cold.
Mom was right -- and now she's backed up by science. Microbiologists at the University of North Carolina in Chapel Hill tested 14 hand-hygiene agents. Everything from soap to alcohol rubs to plain old tap water was tested against hardy bacteria and viruses applied to the hands of 62 volunteers.
Emily Sickbert-Bennett, an epidemiologist at UNC School of Public Health, says, "Really the best thing was plain soap and water." Soap isn't designed to kill bacteria. It acts as a surfactant to lift dirt off of surfaces so it can be rinsed away just like when you use dish washing liquid to remove grease off of dishes.
"We really think it's probably due to the just the physical washing off of those germs," Bennett says. Researchers also discovered just 10 seconds of washing is enough to knock off more than 90 percent of the germs known as microbes. "We know that 10 seconds is effective, and we can focus more on compliance, rather than increasing the length of time you wash your hands."
David Weber, an infectious disease researcher at UNC School of Medicine says, "Because it's not only a droplet disease, meaning three feet, but it is also a contact and touching disease as well." For times you aren't in close contact with a sink, the study revealed alcohol rubs do almost as well, and for parents who have a tough time selling soap -- so did plain old tap water.
Hospitals and health care facilities are paying close attention to this study. That's because health care associated infections rank in the top five causes of death, with an estimated 90,000 deaths each year in the U.S.
BACKGROUND: Nothing works better at getting rid of disease-causing viruses than simply washing one's hands with old-fashioned soap and water. That advice comes from the largest and most comprehensive scientific study ever done to compare the effectiveness of hand hygiene products.
THE STUDY: Scientists at the University of North Carolina at Chapel Hill studied how effective 14 different hand hygiene agents performed in reducing bacteria and viruses from the hands after a 10-second exposure. Previous studies had participants clean their hands for 30 seconds, even though most people, including busy health care personnel, don't spend that much time washing up. Subjects first cleaned their hands, which were then exposed to a harmless bacterium and a virus comparable to disease-causing organisms. Then the subjects cleaned their hands with various agents, after which the scientists measured how much of the bacteria and virus remained. Among the viruses studied is one that causes the common cold, along with viruses that cause hepatitis A, acute gastroenteritis, and other illnesses.
THE RESULTS: The study showed that after a short exposure time of 10 seconds, nearly all the hand hygiene products reduced 90 percent of bacteria on the hands. But waterless alcohol-based hand wipes only removed about 50 percent of bacteria from the subjects' hands.
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http://www.sciencedaily.com/videos/2005/1212-fighting_cold_and_flu_germs.htm
Polymer Sponge Catches Household Pollutants in Storm Drains [and reduced E. Coli]
January 1, 2006 — Storm drains fitted with a spongy material -- a synthetic polymer similar to those used in diapers -- can catch household pollutants such as paint and motor oil as they are washed off by the rain. Twenty-eight states are already using the material to stop pollutants from reaching rivers, lakes and oceans.
SANTA MONICA, Calif.--Oil, grease, deadly bacteria and disease are all found in our ponds, rivers, lakes and oceans. Now, a new invention may be the first step to cleaning up our water.
From traffic to urban sprawl, environmentalist Mark Gold says it all leaves our water sources dirty and polluted. "Everything you can think of is a source, whether it's your car, your next door neighbor, yourself," says Mark Gold, an environmentalist from Heal the Bay in Santa Monica, Calif.
One solution for all this pollution is the Smart Sponge Plus. Rodolfo Manzone, a chemist at AbTech Industries in Scottsdale, Ariz., says, "It is a very simple system based on a combination of synthetic polymers."
The Smart Sponge Plus uses the same material found in diapers, roofing, car bumpers, and glue and has an anti-microbial coating that removes pollutants and destroys bacteria. The sponge is placed in existing storm drains to catch the pollutants before they end up in rivers, lakes or the ocean.
Rodolfo says, "It has the capability to absorb, retain oil, grease and nitrocarbons and to lock them in and create solid waste." The sponge can also kill E. coli bacteria. The water in our lakes or rivers may not be safe enough to drink yet, but it is clean enough to swim in. And that's a step in the right direction.
BACKGROUND: Beach closings due to contamination are becoming more and more of a problem every year, thanks to issues of sewage and storm runoffs. Instead of closing the beaches, why not clean up the water? A new technology not only removes pollutants from water, it also destroys bacteria that can cause illness.
THE PROBLEM: A recent report by the Natural Resources Defense Council (NRDC) found that 85 percent of the beach closings and health advisory days were caused by dangerously high levels of bacterial found in human or animal waste. The NRDC has urged the Environmental Protection Agency to tighten controls over sewer overflows and stormwater discharges to help ensure that states and municipalities monitor water quality and notify the public when it does not meet bacterial standards.
THE SOLUTION: Smart Sponge Plus is a spongelike material that resembles popcorn and can be used to remove hydrocarbons, oil grease and other toxins in water. It also contains an antimicrobial agent to combat common bacteria such as E. coli and fecal coliform. Unlike other antimicrobials that poison harmful microorganisms, the Smart Sponge Plus ruptures the cell membranes, preventing the microorganisms from functioning or reproducing. It can also transform hydrocarbon pollutants into a stable solid for easy recycling. The Smart Sponge can be inserted directly into storm drains, so there is no need to break up roads, build vaults or create ponds. This makes it easier, cheaper and faster to use than other environmental remediation techniques. Smart Sponge Plus is currently being implemented in Rhode Island and Los Angeles.
ABOUT ANTIMICROBIALS: Antimicrobials describe both natural and synthetic substances, including antibiotics and disinfectants, that can kill or slow down the growth of microorganisms such as bacteria and viruses. Sometimes microorganisms can develop a resistance over time to an antimicrobial substance, however, so that it is no longer an effective deterrent. Naturally occurring alternatives could help address this problem.
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http://www.sciencedaily.com/videos/2006/0104-cleaning_up_our_water.htm
Bacteria-Killing Bandage
Biochemists Create Microbicidal Coating to Fight Hospital Infections
March 1, 2006 — New bandages with microbicidal coating kill the most harmful bacteria on contact. The coating is washable and can also be used on hospital gowns and bed sheets, which will help reduce the risk of infection to all hospital patients and staff. Up to 20,000 Americans get hospital infections every year
See also:
Health & Medicine
* Skin Care
* Infectious Diseases
Plants & Animals
* Bacteria
* Microbiology
Matter & Energy
* Medical Technology
* Nature of Water
Reference
* Wound
* Healing
* Maggot therapy
* Inflammation
GAINESVILLE, Fla.--You go there for help, but millions of Americans get sick in hospitals. Hospital infections are growing to epidemic proportions because they're passed from person to person. Now, researchers are working to wipe out these infections with a new bacteria-killing bandage.
Gary Smithson was hit head-on by a drunk driver. The accident put him in a wheelchair, but that is not what keeps him there. It's what happened in the ER -- hours after the crash -- that has made the past 10 years unbearable. During a routine check, doctors found an infection.
Gary is one of 20,000 Americans that leave the hospital each year with an infection they didn't come in with. Gregory Schultz, a biochemist at the University of Florida in Gainesville, is part of a team working to wipe out these super bugs. They've created a microbicidal coating that can kill the most harmful bacteria.
"The microbicidal agent -- that's the thing that kills the bacteria -- is permanently bonded on the surface of the fibers of the dressing," Schultz says.
The bandage on the left is not treated with the microbicidal coating. The area in red is infected with bacteria. Now, look at the bandage on the right. It is treated -- you can see there are no bacteria.
Chris Batich, a biomaterials expert at the University of Florida, says, "What we wound up with is a surface that you can wash. And whenever it touches bacteria, it kills the bacteria ... and keeps on killing them."
The microbicidal coating can also be used on hospital gowns and bed sheets, which will help reduce the risk of infection to all hospital patients and staff.
Because of his infection, Gary believes he will spend the rest of his life in wheelchairs he fixes in his shop. "It's completely changed the way I have to live," he says. Every day is a struggle against an invisible invader that Gary hopes won't claim any more innocent victims.
The bacteria-fighting agent can be used outside the hospital for soldiers in the field to help stop athletes foot. The cost of putting this agent on a bandage is about one cent.
BACKGROUND: University of Florida researchers have led the development of a new type of wound dressing that could keep dangerous antibiotic-resistant bacteria from spreading in hospitals, a problem that leads to thousands of deaths in the U.S. annually. Each year, nearly two million Americans contract infections while hospitalized.
HOW IT WORKS: The new wound dressing features a microbial coating that can be chemically bonded to gauze bandages, socks and even hospital bedding and gowns. This makes the material super-absorbent and pulls excess moisture away from the wound. The microbial coating blocks bacteria from reaching a wound and recolonizing there. It also kills the most common and harmful types of resistant bacteria that cause 70 percent of infections in hospitals, such as staph infections. The fabric can be made into clothing, such as antifungal socks and underwear that could help U.S. soldiers in the field who often don't have time to change or shower. Furthermore, the structure of the coating, and the complexity of the process, makes it nearly impossible for bacteria to become resistant to it. Other dressings use a process that allows molecules to diffuse into the air and into the wound, which can slow healing and increases the chance germs will develop resistance.
WHAT ARE STAPH INFECTIONS? Staph infections result when a bacteria called Staphylococcus aureus enters the body through an open cut or break in the skin. They usually produce pus. Minor staph infections include infections of hair follicles after shaving, or sties, which occur when the follicle surrounding the eyelashes causes a sore red bump in the eyelid. Staph infection is also behind most cases of food poisoning and can also lead to more life-threatening conditions, such as toxic shock syndrome, pneumonia, and infections of the heart of blood. Those in hospitals, with weakened immune systems, are especially vulnerable to staph infection.
HOW WOUNDS HEAL: Controlling moisture and staving off infection are two of the most important aspects of wound healing. All wounds go through the same basic stages of healing. A cavity wound is when a large chunk of tissue has been removed, leaving a hole. Small cavity wounds can be closed with stitches, but larger cavities are more prone to infection and are left open to heal. In open healing, the wound "fills in" from the bottom by building new tissue. As it fills in, the sides of the wound also get new tissue. The sides must be kept from touching until the wound has filled in at least halfway, otherwise they can form bridges, trapping fluids in the wound. A healing wound should look bright red. In the active healing phase, cells multiply, connective tissue cells form collagen, and eventually small red fleshy masses of tissue begin to form. These masses keep growing and contracting until the cavity fills up completely.
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http://www.sciencedaily.com/videos/2006/0304-bacteriakilling_bandage.htm
Antibacterial Implants Could Prevent Infections, Save Patients' Lives
ScienceDaily (Dec. 15, 1999) — University of Washington researchers have developed a method of crafting medical implants from an antibacterial polymer that could prevent thousands of patients from dying of hospital-acquired infections each year.
See also:
Health & Medicine
* Today's Healthcare
* Infectious Diseases
* Pharmacology
Matter & Energy
* Medical Technology
* Electronics
* Materials Science
Reference
* Upper respiratory tract infection
* Salmonella infection
* Urinary tract infection
* Candidiasis
The polymer slowly releases an antibiotic to keep bacteria from establishing a foothold. It could be used to prevent infections around such commonly used devices as catheters as well as more permanent implants, such as pacemakers, according to Buddy Ratner, UW professor of bioengineering and director of the University of Washington Engineered Biomaterials (UWEB) program.
A two-article series on the technique appears in this month's issue of the Journal of Controlled Release.
Infections linked to devices that are inserted into patients are a serious hospital problem, according to Ratner.
"People don't realize that even commonly used devices like catheters account for about 50,000 hospital deaths in the United States each year, many of them because of infection," Ratner said.
Catheters, which are used on patients who require a long regimen of intravenous drugs, are initially sterile, but they can become gathering spots for dangerous microorganisms.
"Once the bacteria get on the device, they are extremely difficult to remove and very resistant to treatment," Ratner said. "It can take 100 times the concentration of an antibiotic to kill the bacteria when they are attached as it takes to kill them when they're free."
The reason may be a protective biofilm that bacteria produce after they become established. When that happens, often the only way to treat the infection is to remove the device from the patient.
The key to stopping infections, then, lies in killing bacteria that come near the device before they form an attachment, Ratner said.
"We found a way to put the antibiotic just on the surface of the device where it interfaces with the body's fluids," he said. "What we've developed is a slowly released micro-aura of the antibiotic. It only takes a small amount because it's right where you need it."
To accomplish that, the researchers first combined the antibiotic ciprofloxacin with a polymer called polyethylene glycol - an approved food additive - and mixed that with the polyurethane used to make medical implants. That made an even, homogeneous material that released the drug in a uniform manner, Ratner said, "but the release was too quick."
To manage the rate of release, researchers used a plasma process to coat the material with an ultrathin layer of another polymer, butyl methacrylate.
When a device is implanted in the body, fluids pass through that thin, permeable outer coating and dissolve the polyethylene glycol, which makes the polyurethane porous. The antibiotic then leaches out of the polyurethane. The coating acts as a barrier to the antibiotic, controlling the rate at which it is released to the surface of the device.
"The outer coating is just 10 or 20 atoms thick," Ratner said. "It makes for a very controlled, slow release."
Tests showed that the system maintains a protective drug cloak for at least five days.
The technology has another advantage for hospital patients - it prevents the development of drug-resistant bugs when some of the bacteria are exposed to an antibiotic and survive.
"With our method, the concentration of the drug is high enough that it kills all of the bacteria that get into the zone around the device," Ratner said.
The first article of the series in the Journal of Controlled Release is co-authored by Ratner, Bioengineering Professor Thomas Horbett and UW bioengineering graduate student Connie S. Kwock in collaboration with researchers in Montana and Connecticut. The second is the work of Ratner, Kwock and Horbett
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http://www.sciencedaily.com/releases/1999/12/991215072051.htm
Amphibian Skin Agent May Battle Multi-drug Resistant Bacteria
ScienceDaily (Jan. 23, 2008) — Researchers from Italy found that a naturally occurring agent in frog skin may inhibit multi-drug resistant bacterial strains associated with hospital-acquired infections.
See also:
Health & Medicine
* Pharmacology
* Infectious Diseases
* Tuberculosis
Plants & Animals
* Bacteria
* Microbes and More
* Frogs and Reptiles
Reference
* Penicillin-like antibiotics
* Antibiotic resistance
* Antiviral drug
* Maggot therapy
Resistance to current antibiotic therapies is on the rise in both hospital and community settings. With some bacterial strains now resistant to every available drug, a return to the preantibiotic era in regard to such infections is cause for great concern. Researchers have identified antimicrobial peptides (AMPs) as one of the most promising candidates for future therapeutic use and they have found amphibian skin to be one of the richest sources of such AMPs.
Nosocomial infections are linked to various drug-resistant bacterial strains and are commonly acquired in a hospital setting as a secondary illness.
In the study researchers tested five AMPs (temporins A, B, and G, esculentin 1b, and bombinin H2) from three different frog and toad species (Rana temporaria, Rana esculenta, and Bombina variegata) for antibacterial activity against multi-drug resistant strains often associated with human nosocomial infections. Initial results showed that all the peptides acted as antibacterial agents against the species tested.
Further studies found that the temporins were more active against gram-positive bacteria; esculentin 1b produced an antibacterial response within 2 to 20 minutes of exposure, and bombinin H2 displayed similar activity toward all bacterial isolates.
“This peptide is an attractive molecule for use in the development of new compounds for the treatment of infectious diseases,” say the researchers.
Reference: M.L. Mangoni, G. Maisetta, M.D. Luca, L.M.H. Gaddi, S. Esin, W. Florio, F.L. Brancatisano, D. Barra, M. Campa, G. Batoni. 2008. Comparative analysis of the bactericidal activities of amphibian peptide analogues against multi-drug-resistant nosocomial bacterial strains. Antimicrobial Agents and Chemotherapy, 52. 1: 85-91.
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http://www.sciencedaily.com/releases/2008/01/080122102502.htm
Pacifying Bacteria Prevents Lethal Post-op Infections
ScienceDaily (Feb. 3, 2004) — Détente, and a good fence, can be far more effective than all-out assault in the age-old war between man and microbe, University of Chicago researchers report in the February issue of Gastroenterology. By injecting a protective coating into the intestines to pacify bacteria there instead of relying on antibiotics to kill them, the scientists were able to protect mice from otherwise lethal infections.
See also:
Health & Medicine
* Gastrointestinal Problems
* Infectious Diseases
* Colitis
Plants & Animals
* Mice
* Bacteria
* Microbes and More
Reference
* Salmonella infection
* Infectious disease
* Nanomedicine
* Colostrum
The protective coating, a high-molecular-weight polyethylene glycol, protected mice who had had major surgery from infection with Pseudomonas aeruginosa, a virulent pathogen that quickly kills 100 percent of untreated mice. A Pseudomonas infection is one of the most lethal complications for patients after major surgery.
"If you can't beat them -- and you can't -- then you want to indulge them," says John Alverdy, M.D., associate professor of surgery at the University of Chicago and director of the study. "An unhappy parasite is programmed to kill the host and move on. So we decided to look for ways to gratify them, to please these powerful microbes and keep them content."
Pseudomonas aeruginosa is common, found in the intestines of about three percent of healthy people. It is also a frequent cause of hospital-acquired infections, especially after major surgery. In the bowel, this germ can be harmless, or it can turn deadly, causing gut-derived sepsis.
"This is a disease of human progress," explains Alverdy. When people are severely ill "we put them in intensive care, where almost every thing we do alarms these bacterial passengers."
Suddenly nutrients no longer pass through the intestines but are dripped directly into the blood stream. The bowel decreases its activity, rendering it far less able to contain the toxic effects of certain strains of bacteria. At the same time, the intestine undergoes erosion of its protective mucus coating.
"Bacteria are smart enough to sense this change and re-program their strategy from peaceful coexistence to one in which harm to their host can occur," Alverdy adds.
Pseudomonas, Alverdy's team has found, detect an ill host's vulnerability by sensing chemicals that indicate stress. They respond like a rival nation -- unhappy with its own boundaries and discovering weakness in a neighbor -- by invading, boring their way through the bowel wall and into the blood stream.
"At this point, bacteria sense that the host is vulnerable and a liability to their survival," says Alverdy. Pseudomonas has tools that let it evade and even disable the host's immune system. It resists antibiotics and it secretes toxins similar to those used by diphtheria or anthrax.
"This is the most lethal of the opportunistic pathogens," he adds. "Patients with widespread Pseudomonas infection can die in a matter of days."
A coating with a high molecular weight polymer however, can form a surrogate bioshield, much like the intestine's own mucus, and stop this whole process before it begins, essentially putting the bacteria at ease.
It prevents the chemical signals of stress from reaching the bacteria and triggering the virulent response. It also serves as a buffer between the bowel wall and the microbes, preventing them from attaching, the first step to crossing the barrier.
The researchers tested the approach by performing major surgery on mice, then introducing Pseudomonas into the bowel, a model that kills all the mice within two days.
One treatment with PEG 15-20, injected into the bowel at the time of infection, however, completely protected the mice. A solution taken my mouth four to eight hours after infection also protected all treated mice.
PEG 15-20 seems to have no adverse effects on the mice and had no effect on bacterial growth or viability. A lighter weight PEG, commonly used as an intestinal cleansing agent (Golytely, PEG-3.35) did not protect mice, although it did have a slight protective effect in the test tube.
Refinement of this approach, say the authors, could prevent hospital infections without using antibiotics.
Grants from the National Institutes of Health, the Packard Foundation and the National Science Foundation supported this work.
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http://www.sciencedaily.com/releases/2004/02/040202065355.htm
Zipper Proteins Hook Up Bacteria And Humans
ScienceDaily (May 9, 2003) — The goal of Magnus Höök's research is to understand the molecular processes that allow bacteria to cause infections. The threat of bacterial infections has become a worldwide concern as many bacteria have developed resistance to previously effective antibiotics. Old pathogens such as Staphylococcus aureus have emerged as "super bugs" that are hard to treat using commercially available antibiotics. Lately, bacteria used as terrorist weapons have also become a threat to our society.
See also:
Health & Medicine
* Infectious Diseases
* Dentistry
* Pharmacology
Plants & Animals
* Bacteria
* Microbes and More
* Microbiology
Reference
* Colostrum
* Pathogen
* Penicillin-like antibiotics
* Antiviral drug
Höök runs an award-winning laboratory at The Texas A&M University System Health Science Center's Institute of Biosciences and Technology (IBT), located in the Texas Medical Center in Houston. His lab's newest research is featured in the May 8 issue of Nature. Teaming up with scientists at Oxford University, UK, they found that disease-causing bacteria might use a specialized zipper mechanism to attach to human cells. The discovery may help shed light on how certain bacteria can invade cells of humans.
"We found that many Staphylococci and Streptococci produce a surface protein that can act as a zipper," Höök explains. Bacteria use this zipper to associate with fibronectin, a protein that links to specific receptors on human cells, allowing the bacteria to gain entry to the host cell.
The report in Nature highlights a novel mechanism for protein-protein interaction and reveals important details of how bacteria cause infections. As bacteria become increasingly drug resistant and cause sometimes-lethal infections, research breakthroughs like Höök's are of critical importance in the search for new strategies to combat these potentially deadly microbes.
The Texas A&M University System Health Science Center provides the state with health education, outreach and research. Its five components located in communities throughout Texas are Baylor College of Dentistry, the College of Medicine, the Graduate School of Biomedical Sciences, the Institute of Biosciences and Technology and the School of Rural Public Health.
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http://www.sciencedaily.com/releases/2003/05/030509090033.htm
[Immediately, what came to my mind was that sounds like a notorious situation that could lead to even worse dangers, like "well, it sounded like a good idea at the time" sort of things...; what happened to ol homeopathy?]
New Approach Could Lower Antibiotic Requirements By 50 Times [by concentrating it and by introducing other phages simultaneously into the body]
ScienceDaily (Jan. 29, 2007) — Antibiotic doses could be reduced by up to 50 times using a new approach based on bacteriophages.
See also:
Health & Medicine
* Infectious Diseases
* Pharmacology
* Today's Healthcare
Plants & Animals
* Bacteria
* Microbes and More
* Microbiology
Reference
* Penicillin-like antibiotics
* Antibiotic resistance
* Upper respiratory tract infection
* Bacterial meningitis
Steven Hagens, previously at the University of Vienna, told Chemistry & Industry, the magazine of the SCI, that certain bacteriophages, a type of virus that infects bacteria, can boost the effectiveness of antibiotics gentamicin, gramacidin or tetracycline.
It is the phages' ability to channel through bacterial cell membranes that boosts antibiotic effectiveness. 'Pseudomonas bacteria for example are particularly multi-resistant to antibiotics because they have efflux pump mechanisms that enable them to throw out antibiotics. A pore in the cell wall would obviously cancel the efflux effect,' Hagens explains.
Pseudomonas bacteria cause pneumonia and are a common cause of hospital-acquired infections.
Experiments in mice revealed that 75% of those infected with a lethal dose of Pseudomonas survived if the antibiotic gentamicin was administered in the presence of bacteriophages. None survived without the phages (Microb. Drug Resist., 2006, 12 (3), 164).
The bacteriophage approach would also be particularly useful for treating cases of food poisoning, because the lower doses of antibiotic needed would not disrupt the friendly bacteria in the gut - a big problem with conventional antibiotic treatments.
'The prospect of using such treatments to prolong the life of existing agents and delay the onset of widespread resistance is to be welcomed,' said Jim Spencer a lecturer in microbial pathogenesis at the University of Bristol.
The overuse of antibiotics since the 1940s had slowly created a host of infections that are resistant to antibiotics. MRSA (Methicillin-resistant Staphylococcus aureus) for example is rapidly spreading through hospitals, affecting more than 8,000 people in the UK every year. MRSA infection can lead to septic shock and death.
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http://www.sciencedaily.com/releases/2007/01/070129081414.htm
Killing Resistant Bugs One Bandage At A Time: Gauze Developed With Microbicidal Coating
ScienceDaily (Sep. 23, 2005) — GAINESVILLE, Fla. - University of Florida researchers have led the development of a new type of wound dressing that could keep dangerous antibiotic-resistant bacteria from spreading in hospitals, a problem that leads to thousands of deaths in the United States each year.
See also:
Health & Medicine
* Skin Care
* Infectious Diseases
* Pharmacology
Plants & Animals
* Bacteria
* Microbes and More
* Microbiology
Reference
* Maggot therapy
* Wound
* Penicillin-like antibiotics
* Antibiotic resistance
This microbicidal coating - which can be chemically bonded to gauze bandages, socks and even hospital bedding and gowns - kills the two most common and harmful types of antibiotic-resistant bacteria that cause infections in hospitals, the researchers said.
According to the National Institutes of Health, each year nearly 2 million Americans contract infections while hospitalized. Antibiotic-resistant bacteria, such as methicillin-resistant staphylococcus aureus and vancomycin-resistant enterococci, cause about 70 percent of those infections.
"Those are the two classes of bacteria that are now epidemic in the U.K.," said Gregory Schultz, Ph.D., director of UF's Institute for Wound Research and one of the inventors who joined with a Gainesville-based company to develop the coating. "It's a huge problem there."
A patent is pending on the researchers' method of chemically bonding the substance to fabrics and other materials. This method allows the substance to be efficiently mass produced and permanently adhered to wound dressings or ready-to-wear clothing to make antifungal and microbicidal socks and underwear.
"What we developed in the lab has to be able to be adapted into industrial manufacturing, and the breakthrough came when we figured out how to do that," Schultz said.
Clothing that kills athlete's foot and other fungi could help U.S. soldiers in the field who often don't have time to change or shower, and the substance also could be added to hospital gowns and bedding to stop the spread of resistant bugs, said Schultz, who also serves as the company's vice president of clinical research and development.
Developed as the ultimate wound dressing, the coating blocks bacteria from reaching a wound and recolonizing there. UF researchers and scientists from the company presented their findings at the Wound Healing Society's annual meeting earlier this year, and the coating's ability to wipe out harmful bacteria and fungi was later confirmed in independent laboratory tests.
The coating also was designed to keep bacteria from becoming resistant to it. Popular silver dressings work well as a bacterial barrier but release ions that allow resistance to develop, Schultz said.
The structure of the microbicidal coating and the complexity of the process make it nearly impossible for bacteria to become resistant to it, Schultz said. The coating comprises thousands of nitrogen clusters that permanently bond to substances such as gauze and fabric. Other dressings use a process that allows molecules to diffuse into the air and into the wound, which can slow healing and increases the chance germs will develop resistance.
"These technologies are especially timely given the threats that are facing the American public, such as antibiotic-resistant bugs occurring in hospitals across the world," said Christopher Batich, Ph.D., a UF professor of biomedical engineering and one of the coating's inventors. "This has the potential to be used widely."
The coating also does what it was created to do - aids healing, Schultz said. When added to gauze, it makes the material superabsorbent, pulling excess moisture away from the sore. And its microbicidal properties keep bacteria from growing in the wound and protect it from infections. Bacteria in a wound "is like jet fuel for these bugs," Schultz said.
"Gauze is still the most commonly used dressing for wounds," he said. "But the problem with gauze is when it absorbs fluid, it forms a great avenue for bacteria and fungus to grow. This treatment actually makes the gauze absorb a little more fluid, (but) it'll keep the wound cleaner because it will keep the bacteria from getting back into the wound."
Clinical trials of the coating in gauze will be conducted at UF later this year.
Controlling moisture and staving off infection are two of the most important aspects of wound healing, said Jeffrey M. Davidson, Ph.D., president of the Wound Healing Society and a Vanderbilt University professor of pathology.
"Control of infection is very important for any type of wound," he said. "Bacteria will produce substances that are harmful to the cells around them. They're trying to colonize. They're trying to make a home for themselves."
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http://www.sciencedaily.com/releases/2005/09/050923075023.htm
Permanent Resistance To Antibiotics Cannot Be Prevented, According To Dutch Research
ScienceDaily (Dec. 27, 2004) — Dutch research has shown that the development of permanent resistance by bacteria and fungi against antibiotics cannot be prevented in the longer-term. The only solution is to reduce the dependence on antibiotics by using these less.
See also:
Health & Medicine
* Diabetes
* Infectious Diseases
* Pharmacology
Plants & Animals
* Microbes and More
* Bacteria
* Fungus
Reference
* Penicillin-like antibiotics
* Spore
* Transgenic plants
* Pathogen
The reduced effectiveness of antibiotics is not only an important issue for human health. For example, plants can have a gene inserted which enables them to secrete an antibiotic against fungi. Siemen Schoustra believes that the added value of these genetically-modified crops is smaller than thought, as the fungus soon becomes permanently resistant to the antibiotic so that the plants still become diseased. The first resistant plant fungi have already been found in India.
Evolution is the cause of the resistance. However this resistance should disappear again, as resistant fungi and bacteria grow less well in an environment without the substance they are resistant to and are therefore outstripped by their faster-growing non-resistant counterparts. Yet, some variants remain permanently resistant.
Permanent resistance occurs in two stages. The fungus first of all becomes resistant due to a change in its DNA and then a second such change ensures that the resistant type eventually grows just as quickly as the non-resistant types. The result is a sort of super fungus, which is resistant and can also grow quickly under all circumstances. This leads to the resistance becoming permanent and therefore the effectiveness of antibiotics being reduced.
Researchers are trying to hinder the development of resistance in bacteria and fungi in an attempt to prevent the antibiotics from becoming obsolete. Their efforts are primarily focussed on understanding and preventing the first stage, whereas the second stage is often omitted. Schoustra's research reveals that hindering the second stage (compensating for the negative effects of resistance) is extremely difficult, as bacteria and fungi can compensate for the negative effects of resistance in so many different ways. Therefore, the only solution is to reduce the dependence on and the use of antibiotics.
The research was funded by the Netherlands Organisation for Scientific Research.
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http://www.sciencedaily.com/releases/2004/12/041219154445.htm
'Alien'-type Viruses May Be Able To Treat MRSA
ScienceDaily (Apr. 2, 2008) — New methods that involve sticking thousands of bacteria-killing viruses to wound dressings are offering ways to prevent hospital operating theatres from spreading infections, scientists heard at the April 1, 2008 at the Society for General Microbiology's 162nd meeting.
See also:
Health & Medicine
* Infectious Diseases
* Today's Healthcare
* Dentistry
Plants & Animals
* Bacteria
* Microbes and More
* Microbiology
Reference
* Colostrum
* Vulvovaginal health
* Penicillin-like antibiotics
* Maggot therapy
Although they are too small to see with the naked eye, bacteria are also attacked by viruses, but specific ones that only infect bacteria, not human or animal cells.
But for bacteria they present a threat like the alien life form in the Hollywood film Alien -- growing inside the bacteria and then bursting out to attack other similar bacteria, continuing their life cycle.
Now doctors are harnessing these little alien creatures to help prevent the spread of hospital superbugs by developing materials impregnated with thousands of tiny beads coated in bacteria-killing viruses.
"Some bacteria specific viruses -- called bacteriophages -- have been used in the past to help clear up infections caused by bacteria, but their use died out when antibiotics like penicillin and methicillin became widely available", says Janice Spencer from the University of Strathclyde in Glasgow, Scotland.
"We are looking at them again now that multiple antibiotic resistant strains of bacteria have become such a problem in hospitals".
The researchers have developed a technique to keep the viruses active for more than 3 weeks, instead of having them die after a few hours, by chemically bonding them to polymers.
The polymers, including nylon, can be in various forms including microscopic beads and strips. Nylon beads can be incorporated into cleaning materials, to decontaminate operating theatres and prevent infections.
The nylon can also be in the form of sutures or wound dressings to decontaminate and prevent wound infection. This limits the risk of blood poisoning, which can be life threatening. Immobilising the bacteriophages onto sutures -- the hospital thread used to stitch up patients during operations -- immediately kills some of the bacteria that would otherwise infect the wound.
This speeds up wound healing and reduces the likelihood of the patient developing a major infection.
Many of the most dangerous bacteria are carried harmlessly on the skin and inside the noses of most healthy people.
It is only when a patient's immune system is weakened by illness or when the bacteria can get inside our bodies during an operation, bypassing the surface defences provided by our skin, that the bacteria develop into their most dangerous, virulent form.
Once activated, some bacteria can cause such serious infections that people may die from them. If these bacteria have also acquired multiple antibiotic resistance, like MRSA, it becomes very difficult, time consuming and expensive to treat the infection.
"We've also developed a device to rapidly detect MRSA on contaminated surfaces. This will allow us to screen patients before surgery to limit the chances of passing on superbug infections by positively decontaminating patients and isolating them to avoid cross-contamination", says Janice Spencer.
"Simple and effective rapid detection of bacteria is important to limit the chance of infection occurring in the first place", says Janice Spencer. "Patients who are carriers for MRSA can be isolated and decontaminated by using standard methods or by using immobilised bacteriophages incorporated into creams or body washes".
The prototype bacteriophage devices for detection and decontamination have been shown to clear MRSA infected surfaces such as tiles and cotton, with the bacteriophages successfully killing 96% of the MRSA strains isolated from patients in 3 different hospitals in the UK and USA.
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http://www.sciencedaily.com/releases/2008/03/080331223805.htm
Scientists Seek To Unwrap The Sweet Mystery Of The Sugar Coat On Bacteria
ScienceDaily (Feb. 14, 2006) — Scientists at The University of Texas at Austin have developed a quick and simple way to investigate the sugar coating that surrounds bacteria and plays a role in infection and immunity.
See also:
Plants & Animals
* Bacteria
* Microbes and More
* Microbiology
Matter & Energy
* Physics
* Biochemistry
* Quantum Physics
Reference
* Escherichia coli
* Colostrum
* Immune system
* Salmonella infection
The sugars coating bacteria can change very quickly during the course of an infection, cloaking the bacteria from the immune system of their host.
Previous techniques for studying the sugars were too slow to catch these rapid changes.
"There's a growing recognition of the importance of carbohydrates on bacterial cell surfaces," says Dr. Lara Mahal, lead researcher and assistant professor of chemistry and biochemistry with the Institute for Cellular and Molecular Biology. "The carbohydrate coating is critical in how your immune system recognizes bacteria."
Mahal and graduate student Ken Hsu report their findings in the advance on-line edition and March issue of Nature Chemical Biology.
The scientists studied the sugar coats of four strains of bacteria: two lab strains of E. coli, one pathogenic strain of E. coli that causes neonatal meningitis, and Salmonella typhimurium, which causes food poisoning.
They analyzed each strain of bacteria using lectin microarrays--small glass plates covered with dots of sugar-binding proteins called lectins.
The lectin dots act like microbe Velcro.
Bacteria with a surface sugar that matches a specific lectin stick to that lectin dot. Because the bacteria are fluorescently labeled, Mahal and her colleagues can read the patterns of glowing dots and determine which sugars coat the bacteria.
The microarray technique worked fast enough that the researchers were able to see the sugar coating change over time in the neonatal meningitis strain of E. coli.
"Over time, the lectins lost their ability to see these bacteria," says Mahal. "This demonstrates that our system is able to see a dynamic change in the carbohydrates on bacteria surface over time."
Mahal says the microarray method could provide an important tool for identifying bacteria and diagnosing infection. It will also provide a way for scientists to start asking questions about the role that surface sugars play in bacterial infection and symbiotic relationships.
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http://www.sciencedaily.com/releases/2006/02/060214230444.htm
Liquid glass: the spray-on scientific revelation
Liquid glass, a revolutionary invisible non-toxic spray that protects against everything from bacteria to UV radiation, could soon be used on a vast range of products.
By Nick Collins
Published: 9:41AM GMT 01 Feb 2010
The spray, which is harmless to the environment, can be used to protect against disease, guard vineyards against fungal threats and coat the nose cones of high-speed trains, it has been claimed.
The versatile spray, which forms an easy-clean coating one millionth of a millimetre thick – 500 times thinner than a human hair – can be applied to virtually any surface to protect it against water, dirt, bacteria, heat and UV radiation.
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It is hoped that liquid glass, a compound of almost pure silicon dioxide, could soon replace a variety of cleaning products which are harmful to the environment, leaving our world coated in an invisible, wipe-clean sheen.
The spray forms a water-resistant layer, meaning it can be cleaned using only water. Trials by food-processing companies showed that sterile surfaces covered with a film of liquid glass were equally clean after a rinse with hot water as after their usual treatment with strong bleach.
The patent for the technology is owned by a German company, Nanopool, which is in discussions with UK companies and the NHS about the use of liquid glass for a wide range of purposes.
Several organisations are said to be testing the product, including a train company in Britain, which is using liquid glass on both the interior and exterior of the train, a luxury hotel chain, a designer clothing company and a German branch of a hamburger chain.
Key to the product's versatility is the fact it can be sold in a solution of either alcohol or water, depending on what surface needs to be coated. The layer formed by the liquid glass is said to be flexible and breathable.
Neil McClelland, Nanopool's UK project manager, told The Independent: "Very soon almost every product you purchase will be protected with a highly durable, easy-to-clean coating ... the concept of spray-on glass is mind-boggling."
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http://www.telegraph.co.uk/science/science-news/7125556/Liquid-glass-the-spray-on-scientific-revelation.html
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