The experience of a clinical trial of bioceramic-based materials in dentistry

Bioceramics-based materials manufactured in Russia were experimentally and clinically tried with the aim of optimizing repair osteogenesis of the jaws. Powder, granules, and porous blocks of hydroxyapatite alone and mixed with tricalcium phosphate may be effectively used for plastic repair of osseous pouches and post-operative defects of the jaws in surgical treatment of periodontitis, periradicular cysts of the jaws, and for filling the wells after removal of teeth.     

The surgical procedure in splenic injuries

An analysis of the character of operations in 106 patients with traumas of the spleen has been made. Organ-preserving operations with a laser scalpel were fulfilled on 28 patients. Absolute indications for performing the organ-preserving operation were revealed in 28% of the patients. Relative indications were found in 53%. Methods of laser coagulation are proposed which helped to preserve the spleen in 46% of the patients during the last 4 years.     

Expression and characterization of a 159 amino acid, N-terminal fragment of human complement component C1s

A 159 residue, N-terminal fragment of the human C1s complement component, C1s alpha(159), was expressed in the baculovirus, insect cell system. The protein was abundantly produced 3 days after infection, reaching levels as high as 40 microg/ml in cell culture media. It had a molecular weight of 18,100 (+/-4.9) Da by laser desorption mass spectrometry, close to the theoretical value of 18,111 Da, confirmed by sequencing. Sedimentation equilibrium and gel filtration column chromatography showed that C1s alpha(159) was a monomer in the presence of EDTA, and a dimer in the presence of Ca2+. The C1s alpha(159)2 dimer had a sedimentation coefficient of 3.1 S. When the C1s alpha(159)2 was mixed with Clq, there was little or no interaction. Likewise, unactivated C1r2 dimer had a sedimentation coefficient of 6.8 S, and when mixed with C1q little or no interaction was observed. When C1s alpha(159)2 was mixed with the 6.8 S C1r2 in Ca2+, a 7.5 S complex was formed, presumably the C1s alpha(159) x C1r x C1r x C1s alpha(159) tetramer. When C1q, which migrated at 10.1 S was mixed with C1s alpha(159)2 and C1r2 in the presence of Ca2+, a C1-like complex, but containing C1s alpha(159) instead of C1s, was formed which migrated at 14.0 S. This C1-like molecule remained unactivated unless challenged with an ovalbumin-antiovalbumin immune complex. In the presence of immune complex, the C1r became activated. This suggested that the presence of the 159 amino acid C1s alpha domain, which held the C1r to the C1q, was sufficient to permit activation by an immune complex, even though the catalytic domains of C1s were not present.     

An improvement in the methods for the microbiological study of the blood from patients with suppurative-septic infections

The new method for microbiological analysis of blood in patients with pyoseptic infections is based on separate inoculations of plasma, erythrocyte mass, and leukocyte layer in nutrient medium providing conditions for growth of a wide spectrum of aerobes and obligate anaerobes. The method in general ensures a more rapid result and permits differentiation between true and false-positive bacteremia and between stages of septic process (bacteremia and septicemia).     

Interaction of catalytically active antibodies with oligoribonucleotides

The interaction of antibodies from blood sera of patients with autoimmune pathology, systemic lupus erythematosus with oligoribonucleotides was studied. The RNA-hydrolyzing activity was shown to be an intrinsic property of autoantibodies. Enzymic activity of antibodies in hydrolysis of poly(U) was estimated at 20-40% of that of RNase A. In contrast to known eukaryotic RNases, the autoantibodies possess a specific RNA-hydrolyzing activity for oligo r(A). The RNA-nicking activity of antibodies in hydrolysis of oligoadenylates was more higher than with hydrolysis of oligo d(A). Optimal conditions of r(pA)13 hydrolysis were selected, including the optimal of pH = 8.7.