Biocompatibility and Bioresorption of 3D-Printed Polylactide and Polyglycolide Tissue Membranes.

We studied biocompatibility and bioresorption of 3D-printed polylactide and polyglycolide tissue membranes. Ultrasound microscopy and histological examination showed that membranes fabricated of a copolymer of lactic and glycolic acids in a mass ratio of 1:9 are bioresorbed and have good biocompatibility with soft tissues (connective tissue, adipose tissue, and epithelium). An important feature of the copolymer membranes, which differs them from pure polylactide membranes, is the formation of a thin fibrous capsule that did not interfere its destruction by the mechanism of hydrolytic resorption.

[Orthotopic bone implants for bone regeneration].

Biotechnology industry is rapidly developing. The elaboration of new biomaterials for bone reconstruction is one of the most perspective directions in tissue engineering. There are millions of surgical operations associated with use of bone graft materials every year.

[Chemiluminescence of daphnia cultivating medium and optimization of conditions for its determination].

The article deals with the optimization of conditions for the chemiluminescence determination. The Daphnia habitat was shown to have no spontaneous chemiluminescence. This was revealed using hydrogen peroxide and luminol, the optimal concentrations of which were 23 and 1.

[Electrochemical sensor based on photopolymeric membranes for determining urea].

A new electrochemical enzymatic sensor based on the ion selective field effect transistors (ISFETs) and photocurable membrane was developed for the determination of urea. For the immobilization of urease on the gate surface of the ISFET a simple method, involving the use of liquid photocurable compositions on the basis of vinylpirollidone, oligouretanemetacrylate and oligocarbonatemetacrylate, was applied. The linearange of the response of the developed electrochemical sensor lies in the range 0.

[Exchange of vitamin D3 in placenta and fetal liver].

Metabolism of [3H]-vitamin D3 in placenta and fetus liver of rats on the 20-21st day of pregnancy was investigated. Biosynthesis in vivo of 25-hydroxyvitamin D3 occurs in placenta and fetus liver and the maximum observed 25-hydroxylation composes 15% in placenta and 13% in the fetus liver. It has been shown, that C-25-hydroxylation of vitamin D3 in the microsomal and mitochondrial fractions of hepatocytes take place.