Doctors claim to have uncovered new evidence that the tiny particles known as "nannobacteria" are indeed alive and may cause a range of human illnesses. The existence of nannobacteria is one of the most controversial of scientific questions - some experts claim they are simply too small to be life forms.
But US scientists report they have now isolated these cell-like structures in tissue from diseased human arteries.
Their research is described in the American Journal of Physiology.
The team, led by Dr John Lieske at the Mayo Clinic in Rochester, conducted an analysis of calcified and non-calcified arteries, arterial plaques and heart valves collected as surgical waste from two US hospitals.
In the lab, they stained the specimens and examined them under a high power electron microscope.
The team found tiny spheres ranging in size from 30-100 nanometres (nm - billionths of a metre), which is smaller even than many viruses.
When the tissue was broken up, filtered to remove anything more than 200nm and the filtrate added to a sterile medium, the optical density - or cloudiness - of the medium increased.
This, the researchers argue, means the nanoparticles were multiplying of their own accord.
"I think we've taken a systematic approach to evaluating the participation of these potential nanoparticles, nannobacteria - whatever you want to call them - in human disease processes," co-author Dr Virginia Miller, also of Mayo Clinic told BBC News Online.
http://news.bbc.co.uk/1/hi/sci/tech/3729487.stm
But US scientists report they have now isolated these cell-like structures in tissue from diseased human arteries.
Their research is described in the American Journal of Physiology.
The team, led by Dr John Lieske at the Mayo Clinic in Rochester, conducted an analysis of calcified and non-calcified arteries, arterial plaques and heart valves collected as surgical waste from two US hospitals.
In the lab, they stained the specimens and examined them under a high power electron microscope.
The team found tiny spheres ranging in size from 30-100 nanometres (nm - billionths of a metre), which is smaller even than many viruses.
When the tissue was broken up, filtered to remove anything more than 200nm and the filtrate added to a sterile medium, the optical density - or cloudiness - of the medium increased.
This, the researchers argue, means the nanoparticles were multiplying of their own accord.
"I think we've taken a systematic approach to evaluating the participation of these potential nanoparticles, nannobacteria - whatever you want to call them - in human disease processes," co-author Dr Virginia Miller, also of Mayo Clinic told BBC News Online.
http://news.bbc.co.uk/1/hi/sci/tech/3729487.stm
