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P Roy

Publications and source records attributed to P Roy.

At least 379 records · Page 21Linked to original sources
PubMed1984

[Progressive complications associated with the use of a bovine heterograft for vascular access].

Three bovine carotid heterografts, used for vascular access, were analysed after removal following the development of aneurysms in two cases and thrombosis in one. The first prosthesis was implanted in a 17-year-old man who suffered from myasthenia gravis and was undergoing plasmapheresis. It became notably dilated several months after implantation, and resection was necessary 14 months after insertion. The second graft was placed in a 31-year-old woman being treated for a severe chronic potassium insufficiency. It was removed 16 months after insertion because of thrombosis. The third bovine carotid heterograft was inserted in a 48-year-old patient on long-term hemodialysis and was removed 3.5 months later because of aneurysmal dilatation adjacent to the arterial anastomosis. These evolutionary and degenerative changes associated with the bovine carotid heterograft illustrate the limitations of this material as an interpositional limb for arteriovenous fistulas in angioaccess therapy. Small weaknesses have sometimes been noted in the microstructure of the graft material studied before implantation.

Adolescent↗
PubMed1983

Homologous terminal sequences of the genome double-stranded RNAs of bluetongue virus.

The 3'-terminal sequences of the 10 double-stranded RNA genome segments of bluetongue virus (serotypes 10 and 11) were determined. The double-stranded RNAs were 3' labeled with [5'-32P]pCp and resolved into 10 segments by electrophoresis. After denaturation, the two complementary strands of segments 4 through 10 were resolved into fast- and slow-migrating species by polyacrylamide gel electrophoresis, and their 3' end sequences were determined. Complete RNase T1 digestion of the individual 3'-labeled double-stranded RNA segments yielded two labeled oligonucleotides, one of which migrated faster than the other on 20% polyacrylamide-7 M urea gels. Sequence analyses of the two oligonucleotides of segments 4 through 10 confirmed the corresponding RNA sequence data. For RNA segments 1 through 3 the oligonucleotide analyses gave comparable results. The 3'-terminal sequences of the fast-migrating RNA species were HOCAAUUU. . . ; those of the slow-migrating RNA species were HOCAUUCACA. . . . Similar results were obtained for double-stranded RNA from bluetongue virus serotypes 10 and 11. Beyond the common termini, the sequences for each segment varied considerably.

Base Sequence↗
PubMed1983

Molecular basis of bluetongue virus neutralization.

Molecular and serological analyses of bluetongue virus serotypes 10 and 11 and their intertype reassortants indicate that the viral RNA segment L2 codes for the serotype-specific antigen. Individual RNA segments of parental and reassortant viruses were characterized by oligonucleotide fingerprint analyses. Analyses of their virion polypeptides by Cleveland peptide mapping (Cleveland et al., J. Biol. Chem. 252:1102-1106, 1977) demonstrated that the L2 gene segregated colinearly with the viral P2 protein, implicating it as the antigen that is responsible for the viral serotype specificity.

Animals↗
PubMed1983

The evolution of bluetongue virus serotype 17.

Four serotypes of bluetongue virus (BTV-10, 11, 13 and 17) have been identified in the United States. Analyses of the genome RNA segments and viral induced polypeptides of U.S. prototype BTV-17 virus by comparison with the corresponding macromolecules of earlier isolates of BTV-11 serotype support the hypothesis that BTV-17 originated by genotypic and antigenic drift from a BTV-11 serotype virus.

Bluetongue virus↗
PubMed1983

Analysis of the genomes of bluetongue virus serotype 10 vaccines and a recent BTV-10 isolate from Washington.

The 10 double-stranded RNA gene segments of 2 vaccinal strains of bluetongue virus (BTV) serotype 10 that are used in the United States (BTV CA8 California and BT-8 Colorado), and a BTV-10 isolate recently obtained from infected sheep in Washington (state) were characterized by oligonucleotide fingerprint analyses. It was determined that although the 2 BTV-10 vaccinal strains are genotypically distinct, they are closely related both to each other and to the United States prototype BTV-10 virus. The BTV-10 field isolate appears to be a naturally occurring reassortment virus with genome segments derived from both United States prototype BTV-10 and BTV-11 viruses. However, one RNA segment of the isolate was totally unlike the corresponding segments of United States prototype BTV-10, -11, -13 and -17 viruses.

Animals↗
PubMed1983

Genetic variation of bluetongue virus serotype 11 isolated from host (sheep) and vector (Culicoides variipennis) at the same site.

Genetic relatedness of 2 strains of bluetongue virus (BTV) serotype 11 that were isolated from the same geographic site--one from host (sheep) and the other from the vector Culicoides variipennis during an enzootic of bluetongue at Bruneau, Idaho, in August 1973--was determined by comparing the oligonucleotide fingerprint analyses of the individual double-stranded RNA segments of the genomes. It was observed that the 2 strains of BTV-11 exhibit considerable differences in their genotypes, the percentage of diversity being different for each of the corresponding RNA species of the 2 strains of BTV-11. These results indicate that more than one genotype of BTV can circulate in juxtaposition in a given geographic site. The observed genotypic diversity might be due to the accumulation of point mutations on specific RNA species or antecedent reassortment of RNA segments between different BTV in nature or both.

Animals↗
PubMed1983

Digital angiography: current status.

Digital angiography depends upon computer recording and manipulation of the radiographic image rather than the use of film. We use a small focal spot x-ray tube, a cesium iodide image intensifier and the image is recorded on a 512 X 512 matrix at 1.2 frames per second. Subtraction angiograms have been obtained in 250 patients and 86% of the results were graded as either good or excellent in head and neck examinations. There is however a small proportion of patients in whom results are unsatisfactory and in whom this fact can be attributed most often to cardiac failure. The advantages of digital intravenous and intra-arterial subtraction angiography have been evaluated and amount to improved patient safety, high system contrast and favourable cost effectiveness; these outweigh the limitations of the restricted field of view and the relatively low resolution of the image in comparison with conventional arteriography.

Aged↗
PubMed1983

Enuresis.

Explore the source record for details and available documents.

Antidepressive Agents, Tricyclic↗
PubMed1983

Gravity large field phlebography of the limbs.

For the last two decades the most common method of radiographic study of the venous system of the lower limbs has been ascending phlebography, by injection of contrast material in a superficial vein on the dorsum of the foot. We report our own experience with another approach, using a large field technique on recumbent patients, with elevation of the limbs, thus taking advantage of gravity. The contrast injection is usually made in a more distal superficial vein of the foot after a tiny cut-down. Excellent results are consistently obtained in demonstrating all the deep veins, including the iliac vessels. The same principles may be applied to upper limb phlebography.

Arm↗
PubMed1982

Analysis of the genomes of bluetongue viruses recovered from different states of the United States and at different times.

The ribonucleic acid (RNA) genomes of the original representatives of the four serotypes of bluetongue virus (BTV) isolated from the United States (BTV-10, BTV-11, BTV-13 and BTV-17) have been analyzed by polyacrylamide gel electrophoresis. Ten double-stranded RNA species were resolved for each virus and categorized into the size classes of large (L segments #1-3), medium (M segments #4-6) and small (S segments #7-10). Minor electrophoretic mobility differences were observed for the M5 and S10 RNA segments of BTV-10 by comparison with the other US prototype viruses. The oligonucleotide fingerprints of the individual RNA species of BTV-11 were obtained and compared to each other providing proof that each of the viral double-stranded RNA species contains unique genetic information. Alternate isolates of BTV-11 isolated in the same year (1973), but from different states (Texas, Idaho, California and Oregon), or in different years (1963, 1970, 1974 and 1975), but from the same state (Colorado), have been analyzed by both RNA gel electrophoresis and L, M and S RNA oligonucleotide fingerprinting. When compared to the individual RNA fingerprints of the US prototype BTV-11 strain, the results indicated that there has been both genetic drift (accumulation of point mutations) and recombination (RNA segment reassortment) for BTV-11 in the United States over a 12-year period since 1963.

Animals↗