[Aneurysm of the extracranial portion of the internal carotid artery combined with kinking of its distal segment]

Presented herein is a clinical case report regarding successful operation for an aneurysm of the left internal carotid artery (measuring 4.5*8.3 cm) combined with pathological tortuosity in its distal portion. The patient was subjected to aneurysmectomy of the left internal carotid artery with prosthetic repair. Kinking in the distal portion of the aneurysm made it possible with minimal technical difficulties to establish a distal anastomosis during prosthetic repair. The diagnosis of an atherosclerotic-aetiology aneurysm was morphologically confirmed.

[Clinical peculiarities of posttraumatic arteriovenous fistulas]

Analysed herein are clinical manifestations of, and outcomes of successful surgical management for postoperative arteriovenous fistulas.

[Cooxidation of phenol and 4-aminoantipyrin, catalyzed by polymers and copolymers of horseradish root peroxidase and Penicillium funiculosum 46.1 glucose oxidase]

Polymers and copolymers of horseradish root peroxidase (HRP) and Penicillium funiculosum 46.1 glucose oxidase (GO) have been synthesized and their catalytic properties have been characterized (free and immobilized forms of each enzyme were studied). The cooxidation reaction of phenol and 4-aminoantipyrin (4-AAP), performed in an aqueous medium in the presence of equimolar amounts of GO and HRP, was characterized by effective K(M) and k(cat) of 0.58 mM and 20.9 s(-1) (for phenol), and 14.6 mM and 18.4 s(-1) (glucose), respectively. The catalytic efficiency of polymerization products (PPs) of GO (GO-PPs) depended on the extent of their aggregation. The combinations GO + HRP-PP and HRP + GO-PP, as well as the copolymer HRP*-GO-PP, proved promising as reagents for enzyme-based analytical systems. When adsorbed on aluminum hydroxide gels, GO-PPs exhibited higher catalytic activity than the non-polymeric enzyme. Maximum retention of GO-PP activity on the inorganic carrier was observed in the case of GO-PP copolymers with an activated HRP. Polymerization of HRP in the presence of a zinc hydroxide gel, paralleled by HRP-PP immobilization onto the gel, increased both the activity of the enzyme and its operational stability.

[Immobilizalion of extracellular glucose oxidase from penicillium funiculosum 46.1 on gels of aluminum or zinc hydroxides]

Different methods of immobilization of extracellular glucose oxidase (GO) from Penicillium funiculosum 46.1 on gels of aluminum or zinc hydroxides have been compared. GO from the culture liquid filtrate (CLF) associated with Zn(OH)2 but not Al(OH)3 gels. Preparation of samples of immobilized GO does not require isolation of the enzyme (CLF may be used). GO immobilized on Zn(OH)2 gels from CLF was 1.6 times more efficient in catalyzing D-glucose oxidation than the enzyme contained in the original culture liquid. Crosslinking of gel-adsorbed CLF proteins affected the properties of GO adversely and to a considerable extent. Various means of polymerization and immobilization of GO isolated from CLF have been studied. Optimum results were obtained when GO polymeric products were pre-synthesized in solution, followed by adsorption to Al(OH)3 but not Zn(OH)2 gels. The catalytic efficiency of GO immobilized on a Zn(OH)2 gel was significantly lower than that of the enzyme associated with Al(OH)3.

[Growth characteristics and glucose oxidase production by mutant Penicillium funiculosum strains]

The main parameters of growth and glucose oxidase production by the mutant Penicillium funiculosum strains BIM F-15.3, NMM95.132, and 46.1 were studied. The synthesis of extracellular glucose oxidase by these strains was constitutive and occurred following the phase of exponential growth. The mutant strains also synthesized extracellular invertase and cell-associated catalase and glucose oxidase. The syntheses of invertase, the cell-associated enzymes, and extracellular glucose oxidase were found to be maximum between 14 and 18 h, between 48 and 52 h, and by the 96th h of cultivation, respectively. Among the mutants studied, P. funiculosum 46.1 showed the maximal rates of growth and glucose oxidase synthesis.

[Quartz sand as an adsorbent for purification of extracellular glucose oxidase from Penicillium funiculosum 46.1]

The procedure of purification of extracellular glucose oxidase (GO, EC 1.1.3.4) from culture-liquid filtrate (CLF) of the fungus Penicillum funiculosum 46.1 using alluvial quartz sand as an adsorbent has been developed. The modification of sand by changing the charge and polarity did not lead to a significant increase in its adsorption capacity towards GO. The effectiveness of sand and aluminum oxide, used as sorbents for isolation of GO from CLF, was compared. Glucose oxidase, isolated from CLF by adsorption on sand, exhibited a greater catalytic activity compared to the enzyme specimens obtained by column chromatography on CLF. Sand adsorbed GO from P. funiculosum 46.1 more effectively than aluminum oxide. It is concluded that sand may be used for fractionation of partly purified GO.

[Intracellular glucose oxidase from Penicillium funiculosum 46.1]

A method for isolating extracellular glucose oxidase from the fungus Penicillium funiculosum 46.1, using ultrafiltration membranes, was developed. Two samples of the enzyme with a specific activity of 914-956 IU were obtained. The enzyme exhibited a high catalytic activity at pH above 6.0. The effective rate constant of glucose oxidase inactivation at pH 2.6 and 16 degrees C was 2.74 x 10(-6) s-1. This constant decreased significantly as pH of the medium increased (4.0-10.0). The temperature optimum for glucose oxidase-catalyzed beta-D-glucose oxidation was in the range 30-65 degrees C. At temperatures below 30 degrees C, the activation energy for beta-D-glucose oxidation was 6.42 kcal/mol; at higher temperatures, this parameter was equal to 0.61 kcal/mol. Kinetic parameters of glucose oxidase-catalyzed delta-D-glucose oxidation depended on the initial concentration of the enzyme in the solution. Glucose oxidase also catalyzed the oxidation of 2-deoxy-D-glucose, maltose, and galactose.

[Selection of Penicillium funiculosum strains with high glucose oxidase activity]

Metabolic inhibitors, riboflavin, and end products of glucose oxidation were shown to hold much promise for the selection of Penicillium funiculosum mutant strains with a high glucose oxidase activity. The incidence of positive mutations was highest in clones resistant to sodium azide, riboflavin, and beta-D-glucono-delta-lactone. Enzyme activity in Penicillium funiculosum mutants was studied under conditions of submerged cultivation. The intensity of glucose oxidase synthesis in seven cultures was 24-56% higher than that in the parent strain of Penicillium funiculosum NMM95.132.

[Preparation and characteristics of mutant strains of Penicillium funiculosum--producers of glucose oxidase]

After the mutagenesis of Penicillium funiculosum with UV light and N-nitroso-N-methylurea, 83 of 2237 grown colonies were surrounded with increased zones of glucose oxidase diffusion. Analysis of the glucose oxidase activity of selected mutant strains grown in submerged cultures allowed 18 mutant strains to be obtained whose glucose oxidase activity was 5-153% higher (in a medium with glucose) and 4-83% higher (in a medium with sucrose) than that of the parent strain. Two of these mutant strains, UV6.31 and NMU95-132, possessed high glucose oxidase activity when grown in media with glucose or sucrose and produced large amounts of mycelia. The active and morphologically stable mutant P. funiculosum NMU95-132 was chosen for further selection work.