Featured Research

from universities, journals, and other organizations

Study: Nitric Oxide-Releasing Materials Might Reduce Medical Implant Infections

Date:
September 13, 2001
Source:
University Of North Carolina At Chapel Hill
Summary:
To varying degrees, medical implants such as catheters, artificial organs and sensors placed under the skin are critical to curing illness or making life better for the infirm, but they also raise the risk of serious infection. More than half of all hospital-acquired infections have been linked to implanted medical devices.

CHAPEL HILL – To varying degrees, medical implants such as catheters, artificial organs and sensors placed under the skin are critical to curing illness or making life better for the infirm, but they also raise the risk of serious infection. More than half of all hospital-acquired infections have been linked to implanted medical devices.

Now studies conducted by University of North Carolina at Chapel Hill chemists show it should be possible to cut that risk significantly by a method that mimics the body’s own self-defense mechanisms.

Led by Dr. Mark H. Schoenfisch, assistant professor of chemistry, researchers have found they can store nitric oxide in sol-gel based materials that could be used to coat implants. Nitric oxide, a natural anti-bacterial agent, is slowly released by the coating when placed in watery environments such as blood or tissue and reduces bacteria’s tendency stick to the implants and form living films that lead to infection.

“Efforts to reduce infections related to medical implants using conventional antibiotic treatments suffer from the widespread problem of emerging resistance from the most troublesome bacterial strains,” Schoenfisch said. “However, local nitric oxide release mimics our body’s own self-defense mechanisms against foreign cells.

“During a process called phagocytosis, immune system cells engulf bacteria and release high levels of reactive molecules, including nitric oxide, to destroy these foreign cells,” he said. “Thus, we hypothesized that polymeric nitric oxide release might represent a new approach for reducing bacterial adhesion and possibly the incidence or severity of infection.”

A report on the research will appear in the Journal of the American Chemical Society this fall, but was posted Sept. 6 on the society’s Web site under ASAP Contents http://pubs.acs.org/journals/jacsat/index.html. Graduate student Brian J. Nablo and former postdoctoral fellow Dr. Ta.-Yung Chen also are authors.

The team created compounds known as aminosilane-based sol-gels as thin films on glass slides. They then converted the amino acid groups to nitric oxide “donors” by exposing the films to high pressures of nitric oxide gas.

Later measurements showed that the compounds released nitric oxide gas continuously for days, Schoenfisch said. Varying the amount and type of aminosilane in the sol-gel could change the rate and amount of nitric oxide release.

To test whether the materials prevented bacterial adhesion, the team then exposed both nitric oxide-releasing and untreated control slides to solutions of Pseudomonas aeruginosa, a common infection-causing bacterium. Bacterial adhesion was as much as 70 percent lower on the nitric oxide-releasing slides.

Preventing bacterial adhesion and biofilm formation is vital for reducing infection since biofilms are extremely resistant to immune system defenses once they have formed on an implant, the scientist said. Such films can cause chronic illness with severe and universal symptoms such as headache, nausea, vomiting, abdominal cramps, sore throat, sore eyes and fever, making diagnosis difficult.

Besides its anti-bacterial adhesion properties, nitric oxide plays a role in several other important physiological processes including blood pressure regulation, nerve transmission, platelet adhesion and tumor cell growth. The impotence drug Viagra relies on nitric oxide action to work, he said.

“People in the biomaterial research community have been struggling for years to control bacterial adhesion,” Schoenfisch said. “Despite the many recent advances in medicine, implant-related infection remains a most serious problem. Polymeric nitric oxide release represents a unique strategy, particularly since nitric oxide has a short half-life in blood -- just a few seconds -- and thus would only have an effect on areas near the implant site where it is needed most.”

UNC’s College of Arts and Sciences supported the studies with start-up funding.


Story Source:

The above story is based on materials provided by University Of North Carolina At Chapel Hill. Note: Materials may be edited for content and length.


Cite This Page:

University Of North Carolina At Chapel Hill. "Study: Nitric Oxide-Releasing Materials Might Reduce Medical Implant Infections." ScienceDaily. ScienceDaily, 13 September 2001. <www.sciencedaily.com/releases/2001/09/010911073242.htm>.
University Of North Carolina At Chapel Hill. (2001, September 13). Study: Nitric Oxide-Releasing Materials Might Reduce Medical Implant Infections. ScienceDaily. Retrieved August 21, 2014 from www.sciencedaily.com/releases/2001/09/010911073242.htm
University Of North Carolina At Chapel Hill. "Study: Nitric Oxide-Releasing Materials Might Reduce Medical Implant Infections." ScienceDaily. www.sciencedaily.com/releases/2001/09/010911073242.htm (accessed August 21, 2014).

Share This




More Health & Medicine News

Thursday, August 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Possible Ebola Patient in Isolation at California Hospital

Possible Ebola Patient in Isolation at California Hospital

Reuters - US Online Video (Aug. 20, 2014) — A patient who may have been exposed to the Ebola virus is in isolation at the Kaiser Permanente South Sacramento Medical Center. Linda So reports. Video provided by Reuters
Powered by NewsLook.com
Raw: World's Oldest Man Lives in Japan

Raw: World's Oldest Man Lives in Japan

AP (Aug. 20, 2014) — A 111-year-old Japanese was certified as the world's oldest man by Guinness World Records on Wednesday. Sakari Momoi, a native of Fukushima in northern Japan, was given a certificate at a hospital in Tokyo. (Aug. 20) Video provided by AP
Powered by NewsLook.com
Do More Wedding Guests Make A Happier Marriage?

Do More Wedding Guests Make A Happier Marriage?

Newsy (Aug. 20, 2014) — A new study found couples who had at least 150 guests at their weddings were more likely to report being happy in their marriages. Video provided by Newsy
Powered by NewsLook.com
Ebola-Hit Sierra Leone's Freetown a City on Edge

Ebola-Hit Sierra Leone's Freetown a City on Edge

AFP (Aug. 19, 2014) — Residents of Sierra Leone's capital voice their fears as the Ebola virus sweeps through west Africa. Duration: 00:56 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins