An investigative team of researchers from the University of Minnesota in Minneapolis and Columbia University in New York City presented their findings Friday at the 83rd General Session of the International Association for Dental Research, convening at the Baltimore Convention Center.
First Report of Direct Link
This is the first report of a direct association between cardiovascular disease and bacteria involved in periodontal disease -- inflammation of the gums that affects an estimated 200 million Americans to various degrees. The research team's findings are published in the journal Circulation.
The researchers collected an average of seven dental plaque samples from 657 subjects (60% female; 56% Hispanic, 23% African-American, 18% Caucasian, 3% Other; average age 69 years). They will re-examine the same group in less than three years, to evaluate the progression of atherosclerosis (heart disease).
They measured both diseased and healthy sites for the presence of 11 oral bacteria -- four widely regarded to be involved in causing periodontal disease, and the other seven serving as controls.
The research, which is published in the current issue of Journal of Periodontology, say that people with periodontal disease who have suffered from an acute myocardial infarction or heartattack are also the ones whose total number of periodontalbacteria in sub gingival plaques were higher than the rest of the participants of the study. Researchers had looked into the gum state of 150 participants who had been suffering from periodontal disease.
In another study, which is also published in the same journal, researchers have reported the DNA strains of the periodontal bacteria in the arteries of the patients. Researchers report that this is due to the fact that a periodontal infection can cause inflammation of the gums that cause opening of pores in the blood vessels of the area around the infection. This makes it easy for the bacteria to travel to other parts of the body by the bloodstream and succeed in causing health problems away from the place of infection.
How long have they known? This page's date says at least 1997:
By Maggie Fox LONDON (Reuter) - British researchers said Tuesday they have found intriguing evidence that a common bacteria can cause heart attacks. They said men who had suffered one heart attack and who had antibodies to Chlamydia pneumoniae were four times more likely to suffer second heart attacks. Treating them for the infection lowered the risk. The findings, published in the American Heart Association journal Circulation, add to a growing body of evidence that heart attacks may sometimes be due to infection rather than genetics or lifestyle. In addition, the chlamydia bacteria, which cause a chest infection and which are a close relative of a common sexually transmitted disease, have turned up in the fatty plaques that line clogged arteries. Gupta's British Heart Foundation team joined the race of >researchers trying to establish a more than circumstantial link between the bug and heart attacks. His team took 213 survivors of heart attacks and divided them into three groups according to how many chlamydia antibodies they had in their blood. They watched for heart attacks for 18 months. ``The group of heart patients with negative antibodies, they had an approximately seven percent event rate over 18 months,'' Gupta said. Those with intermediate levels of antibodies had double that risk, while those with high antibody levels -- meaning bigger chlamydia infection -- had a 28 percent ``event rate'' of heart attacks. That was four times the risk of the group that had no antibodies. ``But the guys that had high antibodies and also got antibiotics, their risk went down to eight percent,'' Gupta added. They were given a single three-day course of azithromycin, although Gupta said he believed several antibiotics such as tetracycline would also have worked. ``This is a small study,'' Gupta noted. He said his team would now start a two-year study with 2,500 volunteers. ``I don't think we are in a position yet to tell people you should be having antibiotics. No way,'' he added. Gupta said he thought chlamydia was causing inflammation, which in turn caused blood clots. The chlamydia was somehow crossing into the arteries, he added. Immune system cells could be the key. ``It's a lung infection but it's found in the coronary,'' he said. ``It may be transported in the monocyte, the warrior, the white cell.'' Activated monocytes produce a chemical on their surface known as tissue factor. Meant to be part of the healing process, it can help trigger blood clotting. Chlamydia was a logical culprit because it was so insidious, Gupta added. It could lurk in the body a long time, causing few symptoms but a lot of damage. ``If you look at other chlamydia species, it's the commonest cause of infertility in the USA,'' he said. ``It causes inflammation of the Fallopian tubes and then it causes scarring.'' With another chlamydial infection, trachoma, blindness is caused in a similar way by scarring eye tissue. If antibiotics could help even a small percentage of people with heart disease, many lives would be saved by something as easy as taking a few tablets, Gupta said.Bacteria could cause heart attacks, study finds
``We know that antibodies seem to be linked to heart disease,'' Dr. Sandeep Gupta at St. George's Hospital Medical School in London, who led the study, said in a telephone interview.
Infection could cause kidney stones - Finnish report on study
WASHINGTON (Reuters) - Tiny little bacteria that build a mineral shell for themselves could be the cause of kidney stones, Finnish researchers said Monday.
They said they found the bacteria, known as nanobacteria because of their small size, in human blood serum and also in kidney stones.
The mineral shells are made out of apatite -- a kind of mineral also found in bones and teeth -- Olavi Kajander and Neva Ciftcioglu of the University of Kuopio found.
``Nanobacteria are the smallest cell-walled bacteria, only recently discovered in human and cow blood and commercial cell culture serum,'' they wrote in their report in the Proceedings of the National Academy of Sciences. Serum is the fluid that forms the base of blood.
Kajander and Ciftcioglu tested human and cow serum. They found nanobacteria in both.
When they let the serum sit in a test tube for a little while, the bacteria settled on the bottom. They quickly developed a thick shell. ``These apatite shelters ... were apparently the dwelling place of the organisms,'' they wrote.
These could be the starting points of kidney stones, which build up layer by layer, something like a pearl forming on a piece of sand inside an oyster. So they looked at kidney stones.
``We performed a pilot survey on 30 human kidney stones to assess whether nanobacteria might be found,'' they wrote.
Tests showed they were in all 30 kidney stones. Blood serum itself, they said, contains chemicals that suppress the formation of mineral layers. But they said they had found earlier that nanobacteria can be transported from the blood to the kidneys.
``Apatite may play a key role in the formation of all kidney stones,'' they concluded.
``In this study, we provide evidence that nanobacteria can act as crystallization centers (nidi) for the formation of biogenic apatite structures,'' they added. They said they were checking to see if nanobacteria were responsible for other calcification diseases in the body. Calcification can be seen in gallstones, for instance.
Leave a comment