Cement the fracture
"Cement" for the complete restoration of bone tissue was made in the Tomsk region
People who have received a fracture or suffer from age-related joint diseases are now being fitted with titanium endoprostheses. However, even the best bioinert materials – titanium or ceramics – due to their foreignness to the human body can only serve for a while, and then they are rejected. The preparation obtained by Seversk scientists – based on biological hydroxyapatite – allows to regenerate bone tissue.
"We have made a material that the body perceives as native. There are mesenchymal stem cells in the bone marrow, which always come to where the tissue is affected. They define our material as a substance capable of participating in biochemical processes, begin to dissolve it and process it in such a way as to be able to share. The division and specialization of stem cells is regeneration. As a result of the biochemical process, native bone tissue arises, with its own blood vessels and nerve cells," said Vitaly Guzeev, Head of the Laboratory of Functional Composite Materials at the MEPhI Research Institute of Nuclear Physics and Technology.
He also explained that now the methods of regenerative medicine mainly involve the transfer of stem cells into the body from the outside, from the incubator. A positive result is achieved only if the cells can be supplied with blood vessels. At the same time, the surgeon must perform a complex operation, and even then the probability that the tissue will take root is 50%.
Hydroxyapatite is a white powder that, when mixed with a biological polymer, gives a substance similar to plasticine. Scientists call it "cement": while you crumple it, it is soft, as soon as you apply it to the damaged bone, the substance becomes hard. Over time, the body dissolves this "cement" and grows its own bone tissue instead. The drug is made from animal bones, due to which its biological activity is preserved. In fact, as the developers explain, these are calcium and phosphorus.
"Based on hydroxyapatite, we have made a liquid material that can be filled into a 3D printer. For example, a person who has suffered a traumatic brain injury is given a CT scan, a picture is sent to a printer, and it prints an element that exactly corresponds to the lost bone area. The material itself becomes solid during the printing process," Professor Guzeev said.
In addition, STI scientists managed to strengthen the biological "cement" to such a state that they can replace titanium plates and screws. Unlike the known resorbable materials, in place of which a cavity remains after their dissolution, hydroxyapatite is replaced by bone tissue.
Hydroxyapatite is produced jointly with the Federal Biomedical Agency and Bioimplant LLC. The material has passed preclinical and partially clinical trials in hospitals in Seversk, Moscow and St. Petersburg, and now the procedure for obtaining a permit for sale is underway. "Cement" will be produced in a box with two syringes: one will be filled with a suspension of hydroxyapatite, the other with a biological polymer. During the operation, the two drugs simply need to be mixed, which a nurse can easily do. Scientists have achieved sterilization of all components, including polymer.
"Another possible application is to inject hydroxyapatite–based drugs to people whose joints begin to ache," as a result of which the calcium-phosphate balance of the body is restored and the pain stops, adds Vitaly Guzeev, head of the STI laboratory.
Portal "Eternal youth" http://vechnayamolodost.ru30.03.2015