Giant thrombosed aneurysm associated with an arteriovenous malformation. Case report

The authors describe a case of giant anterior cerebral artery aneurysm associated with an anatomically related arteriovenous malformation (AVM). The aneurysm was almost completely thrombosed and was resected along with the AVM.

Enzymatic transfer of mannose from mannosyl-phosphoryl-polyprenol to lipid-linked oligosaccharides by pig aorta

A particulate enzyme preparation prepared from the intimal layer of pig aorta catalyzed the transfer of mannose from mannosyl-phosphoryl-polyprenol (MPP) into a series of oligosaccharides that were linked to lipid. The reaction required detergent with Triton X-100 and NP-40 being best at a concentration of 0.5%. Several other detergents were inactive or only slightly active. The pH optima for this activity was about 7 to 7.5 in Tris buffer and the apparent Km for MPP was about 2 x 10(-7) M. The reaction was not stimulated by the addition of divalent cation and, in fact, was inhibited by the high concentrations of cation. The addition of EDTA did not inhibit the transfer of mannose from MPP and was somewhat stimulatory. The transferase(s) activity was "solubilized" from the particles by treatment with Triton X-100. This solubilized enzyme still formed a series of lipid-linked oligosaccharides from either MPP or GDP-mannose. The oligosaccharides were released from the lipid by mild acid hydrolysis and were separated by paper chromatography. Some five or six radioactive oligosaccharides were formed from either MPP or from GDP-mannose and these oligosaccharides had similar mobilities upon paper chromatography. However, MPP was a better donor for the larger oligosaccharides (i.e. those containing 8, 9, or 10 sugar residues), whereas GDP-mannose was better for formation of the oligosaccharide containing 7 sugar residues. In the presence of EDTA and detergent no MPP was formed from GDP-mannose, but radioactivity was still incorporated into the lipid-linked oligosaccharides. Under these conditions essentially all of the radioactivity was in the oligosaccharide containing 7 sugar residues. Since much of this activity could be released as mannose by acetolysis, GDP-mannose may be the direct mannosyl donor for formation of 1 leads to 6 branches. Oligosaccharides 7, 8, 9, and 10 were isolated and partially characterized in terms of their molecular weights, sugar composition, susceptibility to alpha-mannosidase, and 14C products formed by acetolysis and periodate oxidation. The molecular weights ranged from 1310 for oligosaccharide 7 to 1750 for oligosaccharide 10. Hydrolysis of each oligosaccharide and reduction with NaB3H4 gave the expected ratio of [3H]hexitol to [3H]hexosaminitol based on the molecular weight of the oligosaccharide. However, the hexitol fraction contained [3H]mannitol and [3H]glucitol. Since the amount of radioactivity in glucitol was 2 to 4 times that in mannitol and since only glucosaminitol was found in the amino sugar peak, it seems likely that each 14C-oligosaccharide was contaminated with an unlabeled oligosaccharide of equal molecular weight containing glucose and GlcNAc. Acetolysis of the 14C-oligosaccharides gave rise to 14C peaks of mannose, mannobiose, and mannotriose. In the larger oligosaccharides, most of the radioactivity was in mannobiose whereas in oligosaccharide 7 most of the radioactivity was in mannose...

Performance of MA-matched nonretarded and retarded children on measures of field-dependence

Thirty-four nonretarded and 34 EMR children, matched on mental age, were given three tasks relating to Witkin's cognitive style construct. The sample scores of the retarded subjects were consistently lower than the nonretarded subjects' sample scores on each test. The nonretarded children's performance aligned with Witkin's analytical, field-independent cognitive style in contrast to the retarded children's performance which was characterized by a more global, field-dependent style. The results were interpreted in terms of possible cognitive style differences.

Biosynthesis and characterization of lipid-linked sugars and glycoproteins in aorta

A particulate enzyme from bovine aorta catalyzes the incorporation of mannose from GDP-D-[14C]mannose into three products as follows: 1. Most of the radioactivity which is incorporated in short term incubations is into a product that is soluble in CHCl3/CH3OH (2/1, v/v). This product was purified by chromatography on DEAE-cellulose and Sephadex LH-20. The purified glycolipid was stable to alkaline saponification but released [14C]mannose when subjected to mild acid hydrolysis (1/2 = 7 min at 100 degrees in 0.01 N HCl). The purified glycolipid had the same mobility on silica gel plates in an acidic, basic, or neutral solvent system as did glycolipid had the same mobility on silica gel plates in an acidic, basic, or neutral solvent system as did authentic dolichyl mannopyranosyl phosphate. The synthesis of the 14C-mannolipid was reversed by the addition of GDP and Mg2+. 2. [14C]mannose is also incorporated, although at a slower rate into products which are soluble in CHCl3/CH3OH/H2O (1/1/0.3, v/v). When the 1/10.3 soluble material was chromatographed on Avicel plates, it gave rise to three distinct radioactive bands which appear to be lipid-linked oligosaccharides. Mild acid hydrolysis of the 1/10.3 soluble material released water-soluble, neutral 14C-oligosaccharides which eluted from Sephadex G-50 in two or three peaks between the standards cytochrome c and GDP-mannose...

Need associations to acquisition modes, education, and adjustment

3 primary modes of acquisition were defined as the achievement, aggression, and succorance needs of the Murray need system. Picture Identification Test need associations of these acquisition modes were analyzed for 12 male groups differing in education and/or adjustment. Application of t tests to discriminate the 12 groups with 57 need-association variables produced a 5:1 ratio of obtained to chance expected ts (p < .05). Of the 57 variables 51 had significant F ratios (p = .05) for between-within groups variance from a discriminant analysis of the same data. These results indicated that acquisition need association indices are related to personal adjustment and educational achievement.

A kinetic model of membrane repair

Two microelectrodes are inserted into a Xenopus laevis egg. Rectangular current pulses are injected through one microelectrode and the voltage induced across the cell membrane is measured via the second electrode. The transmembrane resistance, as deduced from the injected current and the measured voltage, is taken as a measure of membrane integrity. The cell membrane is punctured with a glass fiber. The fall and subsequent recovery of transmembrane resistance are recorded. It is confirmed that cell membranes do exhibit repair and that repair is enhanced by the presence of calcium ion. A kinetic model of membrane repair is proposed.