Featured Research

from universities, journals, and other organizations

Ulcer Bacteria Linked To Strokes

Date:
July 9, 2002
Source:
American Heart Association
Summary:
Potent strains of ulcer-causing bacteria may play a key role in certain kinds of stroke, researchers report in Circulation: Journal of the American Heart Association.

DALLAS, July 9 – Potent strains of ulcer-causing bacteria may play a key role in certain kinds of stroke, researchers report in today's rapid access issue of Circulation: Journal of the American Heart Association.

For the first time, researchers have found that specific strains of Helicobacter pylori (H. pylori) were much more prevalent in the blood of patients who have suffered an atherosclerotic stroke, says lead author Antonio Pietroiusti, M.D., a professor of internal medicine at Tor Vergata University in Rome.

Some studies have linked H. pylori with inflamed artery walls and arterial lesions, including stroke caused by narrowing of the arteries due to atherosclerosis.

H. pylori causes ulcers in the stomach. In large arteries leading to the brain, the researchers report that cytotoxin-producing strains of the bacteria appear to aggravate an already risky environment. The cytotoxin-associated gene-A (CagA) makes strains of H. pylori virulent and especially damaging to arteries. Cytotoxins attack cells, causing tissue inflammation and ultimately lesions. By attacking vulnerable areas of the artery wall, they cause inflammation and swelling, further restricting blood flow and increasing the chance of stroke.

Researchers compared different strains of H. pylori in the bloodstream of 138 patients with large-vessel stroke (group A); 61 patients with cardioembolic stroke (group B); and 151 healthy volunteers. Extensive atherosclerotic changes cause large vessel strokes, says Pietroiusti. Cardioembolic strokes are caused by abrupt blockage of a cerebral artery by a clot that travels to the brain.

Prevalence of H. pylori infection among patients with large-vessel, , and normal controls was about the same. However, the presence of CagA-positive strains was significantly higher in large-vessel stroke patients than the cardioembolic stroke group — 42.8 percent versus 19.7 percent. It was also higher than those of the controls — 17.9 percent.

Researchers found that only CagA-positive strains of H. pylori are associated with ischemic stroke, and that this association is confined to patients with atherosclerotic stroke.

C-reactive protein (CRP) levels, a measure of systemic inflammation, were also higher in both stroke groups compared with controls. But patients with CagA-positive strains of H. pylori had the highest CRP levels, indicating more severe inflammatory response.

Researchers theorize that the virulent H. pylori may increase system-wide infection, which is known to increase atherosclerosis. Increased infection may also contribute to plaque instability. Unstable plaque can rupture and send a blood clot to the brain, resulting in an ischemic stroke.

Researchers note that more research is needed to confirm their findings.


Story Source:

The above story is based on materials provided by American Heart Association. Note: Materials may be edited for content and length.


Cite This Page:

American Heart Association. "Ulcer Bacteria Linked To Strokes." ScienceDaily. ScienceDaily, 9 July 2002. <www.sciencedaily.com/releases/2002/07/020709055532.htm>.
American Heart Association. (2002, July 9). Ulcer Bacteria Linked To Strokes. ScienceDaily. Retrieved August 27, 2014 from www.sciencedaily.com/releases/2002/07/020709055532.htm
American Heart Association. "Ulcer Bacteria Linked To Strokes." ScienceDaily. www.sciencedaily.com/releases/2002/07/020709055532.htm (accessed August 27, 2014).

Share This




More Health & Medicine News

Wednesday, August 27, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Predicting Heart Transplant Rejection With a Blood Test

Predicting Heart Transplant Rejection With a Blood Test

Ivanhoe (Aug. 27, 2014) — Now a new approach to rejection of donor organs could change the way doctors predict transplant rejection…without expensive, invasive procedures. Video provided by Ivanhoe
Powered by NewsLook.com
Better Braces That Vibrate

Better Braces That Vibrate

Ivanhoe (Aug. 27, 2014) — The length of time you have to keep your braces on could be cut in half thanks to a new device that speeds up the process. Video provided by Ivanhoe
Powered by NewsLook.com
Smartphone App Tracks Your Heart Rate

Smartphone App Tracks Your Heart Rate

Ivanhoe (Aug. 27, 2014) — A new app that can track your heart rate 24/7 is available for download in your app store and its convenience could save your life. Video provided by Ivanhoe
Powered by NewsLook.com
Stroke in Young Adults

Stroke in Young Adults

Ivanhoe (Aug. 27, 2014) — A stroke can happen at any time and affect anyone regardless of age. This mother chose to give her son independence and continue to live a normal life after he had a stroke at 18 years old. Video provided by Ivanhoe
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