Day: 08/25/2015

Identifying the Bacterial Biofilm off Switch .

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We often think of bacteria as a group of rapidly proliferating, free-living cells that don’t typically unite toward a common purpose. However, this couldn’t be further from reality, as microbial existence is much more complex than many may envision. For instance, a number of bacterial species often band together into a collection of cells held tightly together by a tough web of fibers, commonly known as a biofilm. This microbial unification affords the bacteria protection from outward threats such as antibiotics. By way of example, dental plaque, which forms on teeth in between brushings, is the biofilm familiar to most.

In recent years, biofilms have come into the spotlight due to their resistance to common disinfectant protocols—a particular cause for concern within the healthcare industry. In many cases, it becomes impossible to sterilize medical equipment, raising infection rates and necessitating expensive replacements. Consequently, scientists have been on the hunt for ways to prevent biofilms from establishing a foothold.

Now, researchers from the University of Maryland (UMD) believe they have found an important part of the biofilm formation process—the enzyme that shuts down the signals bacteria use to form a biofilm.

“Bacteria form biofilms because they sense a change in their environment. They do this by generating a signaling molecule, which binds to a receptor that turns on the response,” explained lead author Mona Orr, a UMD biological sciences graduate student. “But you need a way to turn off the switch—to remove the signal when it’s no longer needed. We’ve identified the enzyme that completes the process of turning off the switch.”

The findings from this study were published recently in PNAS through an article entitled “Oligoribonuclease is the primary degradative enzyme for pGpG in Pseudomonas aeruginosa that is required for cyclic-di-GMP turnover.”

It had been established previously that the signaling molecule Cyclic-di-GMP (c-di-GMP) was the switch that activates the biofilm formation process in many bacterial species. The UMD researchers, however, identified the molecule that completes the process of clearing c-di-GMP and ceasing the biofilm process. The molecule is an enzyme called oligoribonuclease, and much like c-di-GMP, oligoribonuclease is also common among disease-causing bacterial species.

The investigators studied the process in the bacteria Pseudomonas aeruginosa, a common species known to cause infections in hospital patients. Yet, due to the genetic and physiological similarities between P. aeruginosa and other infectious species, the researchers believe that oligoribonuclease serves the same function across a wide variety of bacteria.

“You can think of this process in terms of water filling a sink. The rate of water from the faucet is just as important as the size of the drain in determining the level of water in the sink,” said co-author Vincent Lee, Ph.D., associate professor in the UMD Department of Cell Biology and Molecular Genetics and the Maryland Pathogen Research Institute. “The level of c-di-GMP in the cell is analogous to the amount of water in the sink. Because no one knew what the drain was, our findings create a complete picture of the signaling process.”

The team found that oligoribonuclease is necessary for the second of a two-step process. The first, converts c-di-GMP into an intermediate molecule called pGpG, then oligoribonuclease breaks apart pGpG and thus completely shuts off the signaling pathway.

The results from the current study suggest that oligoribonuclease could be used to help design new antibiotics, disinfectants, and surface treatments to control biofilms.

“The genes that make these signals are found in most bacteria. The oligoribonuclease enzyme that breaks the effect is only found in some, however,” Dr. Lee noted. “So there must be parallels in the organisms that don’t have oligoribonuclease. Finding these other ‘off’ switches is high on our list of future research goals.”

Easily Reverse Lung Damage With This Important Vitamin | Healthy Life Vision

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COPD or Chronic Obstructive Pulmonary Disease requires thousands of dollars to treat while reducing the quality of your life while fighting against it.

This is why you could treat this ailment in any way you can. You can plant some houseplants in your house which will cleanse the air and fight against your COPD.Easily Reverse Lung Damage With This Important Vitamin

AN INTRODUCTION TO COPD

This term is normally used to describe the condition of chronic bronchitis and emphysema, but it also can be used to refer to any number of chronic lung ailments. In time, it results with lung tissue damage that is irreparable.

COPD is most usual cause of death in the United States, which makes it a very serious problem.

Emphysema is an ailment that kills the alveoli of the bronchioles. When the alveoli are destroyed there will be much fewer air sacs that can transport the air through the body and remove the carbon dioxide out of the body. This will result with fatigue, shortened lifespan and dyspnea.

Chronic bronchitis appears as a result of inflamed bronchial tubes. Once the membranes of these tubes are inflamed, getting rid of phlegm is much harder. This will result with fatigue, wheezing and infections.

THE FOODS YOU SHOULD BE EATING

A research has shown that chronic lung damage can be disabled and reversed with increased amounts of vitamin A, also known as beta carotene. This knowledge hasn’t been used for making a medicine for COPD yet, but you can still use this inflammation and improve your COPD by yourself.

You can eat many vegetables that are loaded with vitamin A which will cure your COPD very fast. Carrots are considered as one of the richest sources of vitamin A. Juice your carrots for easier absorption if you cannot eat large amounts of this vegetable.

USING PLANTS IN YOUR HOME FOR COPD

There are many different house plants that you can use for cleansing the air and make it easier for you to breathe. According to the experts you should hold 15-18 plants for the average 1800 square foot home.

Before deciding to plant those plants, you should make sure that you are up for the task to care for them and keep them alive. Here are the most effective plants for air cleansing:

  • Golden pothos
  • Dracaena
  • Peace lily
  • Bamboo palm
  • Rubber plant
  • Florist’s chrysanthemum
  • Areca palm
  • Chinese evergreen
  • English ivy

Keep in mind that you should always take care of the plants and the soil. While maintaining the soil you will avoid any mold occurrence which leaves negative effect on your COPD.

‘Reprogramming’ cancer cells can reverse tumor – study — RT News

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http://www.rt.com/news/313297-cancer-medicine-science-biology/

Bacterial infection makes farmers out of amoebae .

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A bacterial infection can convert non-farming social amoebae into primitive farmers, new research shows.

In 2011 the Queller-Strassmann lab, then at Rice University, made a startling announcement in Nature Letters. They had been collecting single-celled amoebae of the species Dictyostelium discoideumfrom the soil in Virginia and Minnesota.

While the laboratory strain of Dicty grazes contentedly on bacteria provided for it by its keepers, roughly a third of the wild strains turned out to be primitive farmers. When food was short, they gathered up bacteria, carried them to new sites and seeded the soil with them.

News of the discovery of the “world’s smallest farmer” went viral.

At the time most people assumed that the amoebae were somehow in charge in this relationship. They were, after all, bigger, their spores sometimes contained bacteria, and they ate the bacteria.

Perhaps the farming amoebae had different genes than the non-farming amoebae.

The lab has since moved to Washington University in St. Louis, where David Queller, PhD, is the Spencer T. Olin Professor in Arts & Sciences, and Joan Strassmann, PhD, is the Charles Rebstock Professor of Biology, also in Arts & Sciences.

Now in the August 24 issue of Proceedings of the National Academy of Sciences, joined by postdoctoral research associate Susanne DiSalvo, PhD, they reveal that things are a bit more complicated than first thought.

Bacteria, not amoebae, may be in charge; but not the bacteria the amoebae are farming. There is a third member of this symbiotic relationship.

Surveying the bacteria found in association with their stable farmer clones, they found both both edible and inedible bacterial species, but the assemblage always included bacteria of the Burkholderia genus. This was intriguing because amoeba raised on a lawn of Burkholderia die; this is not a genus of bacteria they find edible.

Investigating further, the scientists soon learned that when they infected nonfarmer amoebae with Burkholderia, the bacteria were transformed into farmers. Once infected, they began to pick up and carry bacterial passengers, such as the food bacteria Klebsiella pneumoniae.

And if farmer strains of amoebae were treated with antibiotics that killed theBurkholderia bacteria, they reverted to the non-farming type and no longer picked up or carried food bacteria.

The scientists concluded that Burkholderia have both pathogenic and beneficial properties; pathogenic ones that facilitate infection and beneficial ones that promote the maintenance of a relationship once established.

Symbiosis apparently benefits all three partners. Dicty that carry edible bacteria are better able to survive starving times; and bacteria that hitchhike on Dicty are dispersed more widely. Dicty sometimes eat the edible bacteria, but the Burkholderia sometimes eat the Dicty.

“Now we know that Burkholderia are the drivers,” said DiSalvo, “likely to benefit by exploiting new terrain and sometimes harming their vehicle in the process.”

Is a universal flu vaccine on the horizon?

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Every fall, millions of people roll up their sleeves for a flu vaccine, hoping to give their immune system a leg up on influenza. But the flu virus has thousands of strains that mutate and evolve across seasons, and the vaccine can’t guard against all of them. Now, two groups of researchers have independently created vaccines that lay the groundwork for a long-sought shot that could protect against every type of flu.

“This is really cutting-edge technology,” says Antonio Lanzavecchia, an immunologist at the Swiss Federal Institute of Technology in Zurich, who is unaffiliated with both studies. “There is still work to do, but this is a clear step forward and it’s headed in the right direction.”

Scientists develop flu vaccines by predicting the strains most likely to infect a population. They use year-round flu surveillance along with field reports from countries in the Southern Hemisphere to guess which strains are most likely to hit North America at the height of the flu season—December through March. But viral guesswork is a tricky business, and it’s impossible to be 100% right. This uncertainty makes for patchy protection, and as flu strains mutate over the course of the season, vaccines become less and less effective.

Flu vaccines stimulate the production of antibodies against pieces of dead virus. Should the virus return, the antibodies can recognize, attack, and neutralize the threat. But because these vaccines are based on parts of the virus that evolve over the course of a flu season, protection is not guaranteed.

To solve this problem, two teams of researchers independently focused on a protein called hemagglutinin, found on the surface of the flu virus H1N1. It has two major components: the head—the portion of the virus that mutates and changes from strain to strain—and the stem, which is similar across most flu strains. The teams tried to remove the variable head region and keep the stem as the base of their vaccines. But hemagglutinin turns out to be rather feeble. Once beheaded, the stem falls apart, and antibodies can no longer bind to it.

To anchor the headless stem, the teams took different approaches. Researchers writing today in Nature Medicine used a two-step method: They introduced a combination of mutations to stabilize the core of the hemagglutinin stem. Then, they bound a bacteria-derived nanoparticle to the stem, which pulled the subunits of the protein together to hold it in the right position. The other team, writing today in Science, applied a combination of mutations that realigned the subunits of the stem at the top. This was enough to sustain a functional structure for the vaccine.

When the teams vaccinated mice, both groups saw full protection against H5N1, a lethal influenza strain distantly related to H1N1. In both studies, mice that did not receive the stem-derived vaccine died, but vaccinated mice all survived. In further experiments, the nanoparticle-anchoring vaccine showed partial protection in ferrets, whereas the other vaccine showed partial protection in monkeys. Two of the six vaccinated ferrets fell ill and died, compared with a 100% mortality rate for the unvaccinated ferrets. None of the monkeys died, but those that were vaccinated had significantly lower fevers than their nonvaccinated companions.

“The [experimental] designs were different, but the end results were very similar and highly complementary,” says Ian Wilson, co-author on the Science paper and a structural and computational biologist at the Scripps Research Institute in San Diego, California. “It’s a promising first step, and it’s very exciting to see this research come to fruition.” Authors of both studies say the next step is expanding protection to other strains of influenza, namely H3 and H7.

Humans carry more superbugs than farm animals

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Humans carry more antibiotic-resistant bacteria than the farm animals they handle, a new study on dairy farmers has found.

Bacteria. Reuters file photo

One of the most common and costly diseases faced by the dairy industry is bovine mastitis, a potentially fatal bacterial inflammation of the mammary gland (IMI).

Researchers studying staphylococcal populations responsible for causing mastitis in dairy cows in South Africa found that humans carried more antibiotic-resistant staphylococci than the farm animals with which they worked.

“The rise of livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) and reported cases of bacterial transmission between dairy cows and humans has raised concerns from both the agriculture/veterinary sector and public health officials,” said lead investigator Tracy Schmidt, from the University of Pretoria.

Staphylococcus aureus is a contagious udder pathogen that readily spreads between cows at milking.

The main source is milk from infected quarters, with milking machine teat liners playing a significant role in the transmission of the bacteria among cows and mammary quarters.

Other Staphylococcus species, collectively referred to as coagulase-negative staphylococci (CNS), often exhibit extensive resistance to antimicrobials and may serve as a reservoir of resistance genes that can transfer and supplement the genome of more pathogenic bacteria like Staphylococcus aureus.

This research analysed the diversity of Staphylococcus populations responsible in South Africa for IMI in dairy cows and assessed the susceptibility of different species to antimicrobials commonly used in the veterinary field as well as human medicine.

Individuals working in close contact with the animals were sampled and the diversity and susceptibility profiles of staphylococcal isolates determined and compared with isolates of animal origin.

With respect to staphylococcal diversity the results showed the clear predominance of Staphylococcus chromogenes among the CNS causing IMI, while Staphylococcus epidermidis was most commonly recovered from the human specimen.

The study found a relatively low occurrence of antimicrobial resistance among the bovine staphylococci.

“This is encouraging as it indicates the responsible usage of antimicrobials within local dairies and provides our veterinary practitioners and animal owners valuable information going forward with respect to the treatment of infected animals,” said Schmidt.

Furthermore, all isolates tested negative for the presence of vancomycin-encoding genes – vancomycin being one of the front-line antimicrobials used for the treatment of methicillin-resistant staphylococcal infections in humans.

The results indicate the low potential health risk posed to close contact workers and milk consumers through exposure to antibiotic-resistant staphylococci originating from milk. The research is published in the Journal of Dairy Science.

Carbon Nanotube Implants Could Help Diagnose Medical Conditions .

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Scientists have long been on the lookout for more efficient ways to identify particular molecules in the body, because their levels can be indicative of dozens of different health conditions. Now a team of researchers has developed implantable carbon nanotubes that light up in the presences of specific molecules, as the scientists announced last week at the meeting of the American Chemical Society and reported in Nature News. That could lead to faster—or even automated—diagnoses of diseases that currently take several days.

Carbon nanotubes are minuscule cylinders made of graphene and coated with another type of polymer—they are flexible and easy to modify for different purposes, which is why researchers have found uses for them in bringing molecules in and out of cells or checking to see if meat has gone bad. To use the nanotubes to diagnose diseases, the researchers designed special polymers that respond in the presence of a biological molecule they’re interested in. A special sensor in the nanotube transmits the signal back to a computer that can process it.

In their presentation the researchers outlined experiments conducted in mice with carbon nanotubes designed to detect insulin, key for diagnosing diabetes; fibrinogen, a protein necessary for blood clot formation and an indicator of liver disease or other inflammatory diseases; and nitric oxide, a molecule the body produces if cancer is present. The researchers engineered the polymers to sense a particular molecule. They tested the carbon nanotubes in blood samples outside the mice, then they implanted the devices inside the mice. The nanotubes worked—they transmitted a continuous signal and, when inside the body, didn’t break down or cause a reaction for 400 days. The nitric oxide sensors in particular worked well, as they were injected into the bloodstream and were even able to pass through the tiny capillaries in the lungs.

Given the cost of carbon nanotubes, it probably makes more sense that traditional blood tests will be used for most types of diagnosis, at least in the foreseeable future. But if carbon nanotubes perform similarly well in humans, they could be useful for continuous monitoring of patients in precarious conditions.

‘Reprogramming’ cancer cells can reverse tumor.

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© Suzanne Plunkett
A team of scientists from Mayo Clinic in Florida have managed to reverse the progress of cancer by “reprogramming” its cells preventing further tumor growth.

It is possible to “turn off” the deadly disease by restoring the function which prevents cells from growing and multiplying uncontrollably, the study published in Nature Cell Biology suggests.

“We have found a new mechanism by which normal cells undergo transition to become tumorigenic,” said Panos Anastasiadis, Ph.D., chair of the Department of Cancer Biology at Mayo Clinic’s Florida campus.

In their normal state, cells are prevented from an uncontrolled growth by a special “glue” which holds them together. This glue is controlled by biological microprocessors called microRNAs. MicroRNA uses a special protein PLEKHA7 as an instrument of regulation.

The scientists discovered that removal of that mechanism switches on cancer development, and vice versa – the mechanism can be restored by delivering MicroRNA molecules to cancer cells, reversing the spread of the disease.

“These [cancer] cells are already missing PLEKHA7. Restoring either PLEKHA7 levels, or the levels of miRNAs in these cells turns them back to a benign state,” Anastasiadis said, as cited by the Telegraph.

The researchers also revealed that the glue, which primarily consists of two proteins – E-cadherin and p120 catenin – actually promotes cancer when it is deprived of PLEKHA7. That means that some molecules have “two faces” – a “good one” when they have a positive function under normal circumstances and a “bad one” when they become harmful due to deviations.

“I think for therapy it is very important because it shows the way we can turn cancerous cells back to a more normal state,” Anastasiadis said.

Experts highlight the importance of the study, but are skeptical about the possible effectiveness of such treatment.

“This important study solves a long-standing biological mystery, but we mustn’t get ahead of ourselves,” said Henry Scowcroft, Cancer Research UK’s senior science information manager, the Telegraph reports.

“There’s a long way to go before we know whether these findings, in cells grown in a laboratory, will help treat people with cancer. But it’s a significant step forward in understanding how certain cells in our body know when to grow, and when to stop,” he added.

“I think in reality it is unlikely that you could reverse tumours by reversing just one mechanism, but it’s a very interesting finding,” concluded Dr. Chris Bakal from the Institute for Cancer Research in London.