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Segregation of all four major fibrillar collagen genes in the Marfan syndrome. 总被引:12,自引:4,他引:8 下载免费PDF全文
D J Ogilvie B P Wordsworth L M Priestley R Dalgleish J Schmidtke B Zoll B C Sykes 《American journal of human genetics》1987,41(6):1071-1082
Linkage markers at or close to the genes encoding the three major fibrillar collagens were used to analyze the segregation of these loci in six pedigrees with dominantly inherited Marfan syndrome. Four pedigrees were discordant at one of the Type I collagen loci (COL1A2), and, of these, two were discordant at the other Type I locus (COL1A1). The Marfan syndrome also segregated independently of the structural loci for Type II and Type III collagen in these two families. This is evidence against the Marfan syndrome being, in general, due to mutations in the major fibrillar collagen genes. 相似文献
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Prevention of guanine modification and chain cleavage during the solid phase synthesis of oligonucleotides using phosphoramidite derivatives. 总被引:9,自引:8,他引:1 下载免费PDF全文
Phosphoramidite reagents can phosphitylate guanine bases at the O6-position during solid phase synthesis and serious chain cleavage occurs if the base phosphitylation is not eliminated before the iodine/water oxidation step. This can be accomplished by blocking the O6-position with a 2-cyanoethyl protecting group for deoxyribonucleotides or with a p-nitrophenylethyl group for ribonucleotides, regenerating the guanine base with water or acetate ions, or using N-methylanilinium trifluoroacetate (TAMA) as the phosphoramidite activator. The effectiveness of these methods was demonstrated by both 31P NMR studies and by the synthesis of d(Gp)23G, (Gp)14G, and d-(Gp)13rG sequences. 相似文献
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A highly sensitive enzymatic assay for diadenosine 5′,5?-P1,P3-triphosphate (Ap3A) has been established on the basis of the coupled luminescence assay for diadenosine 5′,5?-P1,P3-tetraphosphate (A. Ogilvie (1981)Anal. Biochem.115, 302–307). Snake venom phosphodiesterase splits Ap3A into AMP plus ADP which can be measured in a luminescence reaction containing pyruvate kinase, phosphoenolpyruvate and luciferin-luciferase. The procedure is linear with Ap3A levels ranging from 0.1 to 2 pmol. The assay has been used to measure Ap3A in various eukaryotic cells after ion-exchange chromatography and high-performance liquid chromatography of acidic extracts of the cells. The level of diadenosine triphosphate was higher in all instances than the level of diadenosine tetraphosphate. When growing in the abdominal cavity of mice, Ehrlich ascites tumor cells contained high amounts of Ap3A (), allowing direct optical determination in the HPLC chromatography. The quantitative measurement of Ap3A with the luminescence assay gave identical results. Ap3A extracted from Ehrlich cells was also chromatographed with authentic nucleotide in two thin-layer systems providing additional proof for the existence of Ap3A in biological material. 相似文献
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Colin Ogilvie 《BMJ (Clinical research ed.)》1966,1(5489):735-736
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Thrombospondin binding to specific sequences within the A alpha- and B beta-chains of fibrinogen 总被引:2,自引:0,他引:2
T Bacon-Baguley M L Ogilvie T K Gartner D A Walz 《The Journal of biological chemistry》1990,265(4):2317-2323
Thrombospondin is a multifunctional adhesive glycoprotein which binds to the surface of resting and activated platelets. Thrombospondin also binds to a variety of proteins, including fibrinogen. The interactions between platelet-bound thrombospondin and fibrinogen are thought to facilitate irreversible platelet aggregation. Both the A alpha- and B beta-chains of fibrinogen specifically bind to thrombospondin. Cyanogen bromide cleavage products of the fibrinogen A alpha- and B beta-chains, and synthetic peptides corresponding to specific regions of these cleavage products were utilized to identify the regions of the fibrinogen A alpha- and B beta-chains which bind to thrombospondin. Cyanogen bromide fragments of the A alpha- and B beta-fibrinogen chains, resolved by gel filtration and reversed-phase chromatography, were examined for thrombospondin binding activity. Thrombospondin specifically bound to the A alpha-chain fragment encompassing residues 92-147 and the B beta-chain fragment encompassing residues 243-305. Analyses of the binding characteristics of two series of overlapping synthetic peptides revealed that peptides corresponding to residues 113-126 of the A alpha-chain and residues 243-252 of the B beta-chain retained thrombospondin binding activity. Separate bovine serum albumin conjugates of the active A alpha-chain and B beta-chain peptides inhibited platelet aggregation. These studies reveal that fibrinogen possesses at least two unique sequences which are recognized by thrombospondin and that such interaction may affect platelet aggregation. 相似文献
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The histochemical demonstration of quantitative differences in myofibrillar ATPase activity at the selective pH optima of the various types of human skeletal muscle fibers is the most widely used technique for their differentiation. The basis of the reaction is the deposition of insoluble salts of inorganic phosphate cleaved from ATP by myofibrillar ATPase(s) followed by substitution of the phosphates with less soluble chromogenic salts. Doriguzzi and associates reported using metachromatic dyes to demonstrate quantitative differences in phosphate deposition among different fiber types. Following routine ATPase histochemistry and staining with either azure A or toluidine blue, fibers with low ATPase activity (and low phosphate content) were stained metachromatically while fibers with high ATPase activity (and high phosphate content) were orthochromatic with the intensity of color proportional to the content of insoluble phosphate. The metachromasia was readily lost after immoderate washing in aqueous solutions or routine dehydration in ethanol, with consequent diminished fiber type distinction. A critical modification of this technique is reported in which incubation of frozen sections of human skeletal muscle in ATP-containing medium is carried out at room temperature (22-24 C), rather than the usual 37 C., followed by a revised washing and dehydration protocol. With these modifications, the four human skeletal muscle fiber types (types I, HA, IIB, and IIC) can be identified rapidly and reliably in single sections, obviating the need for examination of serial sections. The tinctorial differentiation allows fiber type identification even in black and white photographs. 相似文献
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Methanogenic Activity and Structural Characteristics of the Microbial Biofilm On a Needle-Punched Polyester Support 总被引:2,自引:0,他引:2 下载免费PDF全文
Martin Harvey Cecil W. Forsberg Terry J. Beveridge Jack Pos John R. Ogilvie 《Applied microbiology》1984,48(3):633-638
In a downflow stationary fixed-film anaerobic reactor receiving a swine waste influent, few bacteria were observed to be tightly adherent to the surfaces of the needle-punched polyester support material. However, there was a morphologically complex, dense population of bacteria trapped within the matrix. Frequently large microcolonies of a uniform morphological type of bacteria were observed. These were particularly evident for methanosarcina-like bacteria which grew forming large aggregates of unseparated cells. Leafy deposits of electron-dense, calcium- and phosphorus-enriched material coated the polyester matrix and some cells. As the biofilm matured there was more extensive mineral deposition which completely entrapped cells. The entrapped cells appeared to autolyze, and many were partially degraded. Further impregnation of the matrix with minerals and apparent cell death may eventually have a deleterious effect on the methanogenic activity of the biofilm. 相似文献