Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study examines whether giving good bacteria reduces infections

03.03.2004


Whether giving good bacteria that normally helps keep the intestinal tract and immune system healthy can reduce infections in intensive-care patients is the focus of a new clinical study at the Medical College of Georgia.


Dr. Robert G. Martindale, gastrointestinal surgeon and nutritionist, is giving ICU patients back good bacteria to see if it can help them avoid infections.



"When people are admitted to intensive care on broad-spectrum antibiotics, we know that 25 to 40 percent of them will get an infection with a resistant bacteria during their stay," says Dr. Robert G. Martindale, gastrointestinal surgeon, nutritionist and principal investigator on the new study.

As the name indicates, these antibiotics are designed to protect patients from infection by a broad range of agents. However, they also can wipe out the natural bacterial flora in the intestinal tract, a disruption with widespread consequences including making the intestinal lining more susceptible to bacterial invasion, impacting the health of colon cells and disarming the immune system.


"We kill all the normal bacteria in our GI tracts, allow these abnormal bacteria to grow and we are in trouble, we have upset the balance," says Dr. Martindale who restores the balance in patients who arrive at MCG Medical Center critically ill from sepsis following routine surgery.

He first prescribes more targeted antibiotic therapy, then returns some of the primary healthy bacteria, such as lactobacillus plantarum, that play many important roles including maintaining a healthy intestinal lining, protecting from invaders such as Salmonella and E. coli, encouraging the activity of macrophages, an immune system component that gobbles up invaders and preventing diarrhea.

"We know very well that the source of sepsis in these patients, 50 to 70 percent of the time, is their own intestines," Dr. Martindale says. "The question is, ’Why?’ Why do bacteria from our own intestines that normally live with us in a nice, healthy relationship become aggressive and infective? Because we give these broad-spectrum antibiotics, we have big operations, GI bleeds … all these things destroy the normal lining of the intestines. Now these bacteria become aggressive."

Giving good bacteria, called probiotics, is accepted therapy in many countries. But even though the bacteria can be found on grocery-store shelves, the therapy has not caught on in the germ-vigilant U.S.A., Dr. Martindale says.

"Americans don’t like the concept," he says, and because the bacteria already are available and affordable, there is little financial incentive for pharmaceutical companies to get involved, although a company not involved in making probiotics is sponsoring his new study.

He hopes the study, the country’s first large, randomized trial to assess probiotics’ effectiveness in reducing infections in ICU patients, will help change that.

Eligible patients include those on broad-spectrum antibiotics admitted to adult ICUs at MCG Medical Center. Louisiana State University in Shreveport also will enroll patients and the University of Maryland in Baltimore likely will as well, Dr. Martindale says.

He plans to enroll a total of 400 patients in one of three study arms he designed. Twice a day for 10 days, patients will receive either a placebo, probiotics or probiotics in conjunction with non-digestible fibers called prebiotics, which encourage the growth and activity of good bacteria. Pairing prebiotics and probiotics is called symbiotics.

"These bacteria are good," says Dr. Martindale and it’s not just hospitalization and antibiotics that are destroying them. Rather, it’s the American lifestyle in general, with its emphasis on cleanliness and a diet low in fiber and high in refined, processed food that is weakening the natural, protective mechanisms of the gut and surrounding immune cells. "Humans that eat a good mixed diet with lots of fiber have plenty of Lactobacillus plantarum. Americans have little," he says.

Dr. Martindale has spent two years exploring probiotics’ potential in restoring a healthy, normal flora including collaborating with Dr. Vadivel Ganapathy, biochemist and interim chair of the MCG Department of Biochemistry and Molecular Biology, who studies nutrient transport systems.

In research currently published as an accelerated communication in the Journal of Biological Chemistry, Dr. Ganapathy helps explains the importance of eating fruits and vegetables and not abusing antibiotics. His work details SLC5A8, a transporter that he has found delivers short-chain fatty acids to colonic cells to help keep them healthy. This was a missing piece of the puzzle of how the colonic cells use glucose found in the indigestible plant cells walls that make it to the colon. Good bacteria produce an enzyme that enables the glucose to be released. In the process of fermenting this glucose so it can be used as energy, bacteria also produce energy-packed short-chain fatty acids.

Dr. Ganapathy found that the transporter, SLC5A8, delivers these fatty acids to colon cells. When colon cells don’t get enough of this preferred nutrient, they can become sick and cancerous. Drs. Martindale and Ganapathy are pursing the idea that the transporter also delivers short-chain fatty acids to nearby immune cells to keep them healthy as well. The gastrointestinal tract, which runs a path through the middle of the body, has more immune cells than any other part of the body, Dr. Martindale says. Those immune cells must stay vigilant so they can assess everything that moves through the tract.

"Clearly, the National Institutes of Health, the National Cancer Institute, all of the national organizations will say to lower your risk of cancer, you need to eat mixed fruits and vegetables," Dr. Martindale says. "And, if we eat more fruits and vegetables, it fits right along with this, you get more fiber, you get more fermentation substrates to the bacteria that live in your colon. If you start looking at the data on what bacteria do for us, there truly is a mutualistic relationship between us and the bacteria that live in our colon."

Toni Baker | EurekAlert!
Further information:
http://www.mcg.edu/

More articles from Health and Medicine:

nachricht New malaria analysis method reveals disease severity in minutes
14.08.2017 | University of British Columbia

nachricht New type of blood cells work as indicators of autoimmunity
14.08.2017 | Instituto de Medicina Molecular

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>