"Nanoshiki" for cleaning vessels

Preface (from a Healthy Skeptic)To begin with, read how this news was presented by our very respected colleague from the daily e-newspaper " <url>".

Very impressive, especially the picture: a giant combat nanorobot is drilling a mine in an artery clogged with a stroke thrombus.

Nanotechnology seems to be really starting to help humanity. At least, scientists from Harvard Medical School and the Massachusetts Institute of Technology tried to prove this: they have created the smallest particles that can clear the arteries and improve well-being.

The development, as the researchers note, is still at the testing stage. However, if it gets into mass production, it will be able to help millions of people around the world suffering from cardiovascular diseases.

Scientists called their creation a nanobur. Particles of the developed substance penetrate into the human circulatory system and literally drill any neoplasms that interfere with blood flow. The particles themselves do not harm the vessels and the body.

The university, where the technology was developed, notes that the novelty perfectly replaces expensive and ineffective (compared to nanoparticles) preparations for cleaning blood vessels. In addition, the use of such a method saves a person from having to perform surgery if there are problems with the cardiovascular system.

"This is an excellent example of the use of nanotechnology in healthcare. The particles are injected using a conventional injection," comments Robert Langer, a professor at the Massachusetts Institute of Technology, one of the authors of the nanobur development, on the advantage of his invention. He also adds that no side effects from the use of nanoparticles have been recorded so far.

The technologies for making such notes are described in the article "Funny pictures about the adventures of scientific news".
But in fact, everything (except the names of the organizations in which these scientists work) is not so at all, but exactly the opposite:

"Nanoshiki" for cleaning vesselsResearchers at the Massachusetts Institute of Technology and Harvard Medical School, working under the guidance of Associate Professor Omid Farokhzad, have developed targeted nanoparticles capable of attaching to the walls of arteries and slowly releasing drugs.

The results of their work were published on January 19 in the preliminary on-line version of the journal Proceedings of the National Academy of Sciences in the article "Spatiotemporal controlled delivery of nanoparticles to injured vasculature". 

Nanoparticles are called 'nanoburrs' due to the fact that their surface is covered with spikes of protein fragments that ensure their strong attachment to specific proteins of the damaged arterial wall (the word 'burr' has many meanings, including "spike", "burdock", "milling cutter"). Certain modifications of such nanoparticles can gradually release the drug for almost two weeks, which makes them a promising alternative to drug-releasing stents used in the treatment of some patients with cardiovascular diseases.

"Nanosheets" (or "nanorepeins", if you like) are spheres with a diameter of 60 nanometers, consisting of three layers: an inner core, represented by a complex of a drug and polylactic acid, a middle layer of soy lecithin with lipid properties and an outer shell of polyethylene glycol that protects the nanoparticle during its circulation in the bloodstream.

Nanoscips bind specifically to the basement membrane lining the walls of the arteries and are exposed only if they are damaged. This makes it possible to use such nanoparticles for the treatment of atherosclerosis and other inflammatory diseases of the cardiovascular system. During the experiments, the authors loaded nanoparticles with paclitaxel, a drug that suppresses cell division and prevents the formation of scar tissue narrowing the lumen of arteries.

The cleavage of the drug molecules from the polymer chain occurs gradually as a result of the reaction of hydrolysis of esters. The longer the polymer chain, the longer the reaction takes, which allows you to control the duration of drug release. To date, in experiments on cell cultures, the authors have managed to achieve the release of the drug for more than 12 days.

In experiments on rats, the researchers demonstrated that nanoparticles injected into the tail vein successfully reach damage zones in the left carotid artery. At the same time, the number of "nanoscips" attached to the damaged arterial wall was twice as large as the number of attached control nanoparticles that do not have guiding proteins on the surface.

The possibility of intravenous administration of nanoparticles and prolonged release of drugs will save patients from multiple invasive interventions directly in the area requiring treatment. In addition, the authors believe that the technique they developed will find wide application in the treatment of other common diseases, including cancer and inflammatory diseases, in which vascular lesions are often observed.

The developers hope that over time, the new nanoparticles can be used as an additional means to increase the effectiveness of vascular stents, the introduction of which is the standard method of treatment in most cases of arterial patency disorders. In cases where it is impossible to insert a stent, for example, when a site located in the immediate vicinity of an artery branching is affected, nanoparticles can be used as an alternative to stents.

Evgenia Ryabtseva, Alexander Chubenko
Portal "Eternal youth" http://vechnayamolodost.ru according to MIT materials: New 'nanoburrs' could add to arsenal of therapies against heart disease

20.01.2010