METABOLIC, ENZYMATIC AND MINERAL MAINTENANCE OFREPARATIVE OSTEOGENESIS OF FACIAL CRANIUM INJURIES.

Aim - study of marker enzymes, hormonal and carbohydrate-protein indicators of the state of reparative osteogenesis in patients with complicated and uncomplicated course of injuries of facial cranium. The study included 81 patients with injuries of facial cranium, which were divided into 2 groups, depending on the presence of complications. The following enzyme indicators were studied: the level of excretion of hydroxyproline in daily urine; alkaline and acid phosphatase activity; the percentage of bone isoenzymes of alkaline phosphatase. To assess the mineral metabolism, the level of total and ionized calcium and inorganic phosphorus in the blood serum, as well as their excretion in the urine, were determined. To assess the state of metabolism, the concentration of glycosaminoglycans and their fractions in the blood serum were studied. To study the structural and functional state of the bone tissue the densitometry was performed. In patients with complicated course of injuries of facial cranium assosiated with traumatic brain injury there was revealed the increase (р<0,05) of: excretion of phosphorus, uronic acids and oxyproline, while the excretion of calcium was not disturbed (р>0,05), and excretion of magnesium was decreased (р<0,05). It was found out that the level of calcium of blood serum in patients with complicated course is significantly (р<0,05) lower than in the control group and does not depend on the presence of craniocerebral injury (р>0,05). The decrease of the level of ionized calcium content in blood serum can be the confirmation of lower metabolic activity of reparative osteogenesis processes, first of all at the expense of damage of central mechanisms. When studying the content of carbohydrate-protein metabolites by complicated course of injuries of facial cranium, the absolute increase (р<0,05) of concentration of chondroitin-6-sulfates was revealed, and during the analysis of results it was found out that in absolute values, as well as in structural indexes, the specific weight of various fractions changes, that can be the evidence of instability of mechanisms of osteogenesis and of damage of physiological mechanisms of reparative osteogenesis. Densitometric equivalents of forming of complicated course of injuries of facial cranium are the increase of broadband ultrasonic attenuation and the decrease of its spreading speed on the background of low levels of chondroitin-6-sulfates.

The inclusion of zinc into mineralized collagen scaffolds for craniofacial bone repair applications.

Implant osteoinduction and subsequent osteogenic activity are critical events that need improvement for regenerative healing of large craniofacial bone defects. Here we describe the augmentation of the mineral content of a class of mineralized collagen scaffolds under development for craniomaxillofacial bone regeneration via the inclusion of zinc ions to promote osteogenesis in vitro. Zinc is an essential trace element in skeletal tissue and bone, with soluble zinc being shown to promote osteogenic differentiation of porcine adipose derived stem cells. We report the development of a new class of zinc functionalized scaffolds fabricated by adding zinc sulfate to a mineralized collagen-glycosaminoglycan precursor suspension that was then freeze dried to form a porous biomaterial. We report analysis of zinc functionalized scaffolds via imaging (scanning electron microscopy), mechanical testing (compression), and compositional (X-ray diffraction, inductively coupled plasma mass spectrometry) analyses. Notably, zinc-functionalized scaffolds display morphological changes to the mineral phase and altered elastic modulus without substantially altering the composition of the brushite phase or removing the micro-scale pore morphology of the scaffold. These scaffolds also display zinc release kinetics on the order of days to weeks and promote successful growth and pro-osteogenic capacity of porcine adipose derived stem cells cultured within these zinc scaffolds. Taken together, we believe that zinc functionalized scaffolds provide a unique platform to explore strategies to improve in vivo osteogenesis in craniomaxillofacial bone injuries models. STATEMENT OF SIGNIFICANCE: Craniomaxillofacial bone defects that arise from traumatic, congenital, and post-oncologic origins cannot heal on their own and often require surgical intervention. We have developed a class of mineralized collagen scaffolds that promotes osteogenesis and bone regeneration. Here we describe the inclusion of zinc sulfate into the mineralized collagen scaffold to improve osteogenesis. Zinc functionalized scaffolds demonstrate altered crystallite microstructure but consistent Brushite chemistry, improved mechanics, and promote zinc transporter expression while supporting stem cell viability, osteogenic differentiation, and mineral biosynthesis.

Alteraçöes eletrolíticas do potássio em pacientes portadores de traumatismos faciais submetidos a terapêutica cirúrgica / Electrolytic changes of the potassium in patients carrying facial traumatisms submitted to surgical treatment

Análise bioquímica das alteraçöes eletrolíticas do potássio, na saliva humana mista, soro e urina em pacientes traumatizados da face submetidos a terapêutica cirúrgica, obtendo resultados conclusivos destas alteraçöes em relaçäo ao grupo controle