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S Doyle

Publications and source records attributed to S Doyle.

65 records · Page 4Linked to original sources
PubMed1986

New mutation and prenatal diagnosis in ornithine transcarbamylase deficiency.

Ornithine transcarbamylase (OTC) (E.C.2.1.3.3) is an X-linked hepatic enzyme in the urea cycle necessary for ammonia detoxification. Deficiency of OTC results in neonatal hyperammonemia, coma, and death in childhood. Because fibroblasts do not express OTC, prenatal diagnosis in the past has required fetal liver biopsy. Using a complementary DNA (cDNA) for OTC for Southern blot analysis of genomic DNA, we have found probands with complete OTC deficiency from two unrelated families in whom the same TaqI restriction endonuclease site has been altered because of independent, but not necessarily identical, mutations in the OTC gene, suggesting that this site may be a relative hotspot for mutation at a location that is critical for normal gene function. This TaqI alteration has allowed the identification of the individual in each family in whom the mutation originated as well as the exclusion of a recurrence of OTC deficiency in a male fetus at risk for the disease. OTC deficiency joins the growing list of genetic disorders for which Southern blot analysis allows accurate heterozygote detection and prenatal diagnosis in conditions for which they were not previously available.

Child, Preschool↗
PubMed1985

Accurate ultrasonic estimation of fetal weight.

The accuracy of eight ultrasonic fetal weight formulas were analyzed in 1099 fetuses who underwent real-time ultrasound examination within 72 hours prior to delivery. Shepard's formula was most consistently found to give the lowest systematic and random errors throughout all weight categories, though Deter's formula had an almost identical accuracy. The Shepard formula was further analyzed in respect to the effects of fetal sex and birthweight centile grouping on the accuracy of fetal weight estimation. The results indicated that fetal sex had no effect on the accuracy of fetal weight estimation, but that birthweight centile grouping did. The weights of small-for-gestational age infants were systematically overestimated, while the weights of large-for-gestational age infants were systematically underestimated.

Birth Weight↗
PubMed1984

Ultrasonic diagnosis of altered fetal growth by use of a normal ultrasonic fetal weight curve.

A previously developed normal ultrasonic fetal weight curve was used for antenatal diagnosis of altered fetal growth in 595 patients who had undergone real-time ultrasound examination within 72 hours before birth. Fetal weight was estimated using biparietal diameter and abdominal circumference and plotted on the normal curve. The diagnosis of small for gestational age (SGA) or large for gestational age (LGA) was based on whether the ultrasonic weight fell below or above the normal limits. After delivery, infants were classified as SGA, LGA, or average for gestational age (AGA) by birth weight, and the postnatal diagnosis was compared to the antenatal ultrasound diagnosis. The sensitivity of the technique for the diagnosis of SGA infants was 89.9%; for LGA it was 73.5%. The overall specificity of the technique was 79.8%.

Birth Weight↗
PubMed1980

Variability in derivative strains of Bordetella pertussis.

Bordetella pertussis strain UT25 was isolated on Bordet-Gengou(B-G) agar from a child with whooping cough in 1977. Derivative strains were isolated from UT25 by serial passages on Trypticase Soy Agar (TSA) containing blood,followed by serial passages on plain TSA. At passage 69, UT25 was subcultured in parallel on TSA and B-G. For experiments, strains were grown in defined liquid medium, adjusted to a standard turbidity, and tested in parallel. Tests were performed to detect changes in immunogenicity, production of dermonecrotic toxin, histamine sensitizing ability, serologic properties, infectivity for mice by the intranasl route, production of adenylate cyclase, patterns of outer membrane proteins. Notable changes occurred in the properties of UT25 at passage 16, just when stable growth on blood-fresh medium was established. After 5 additional passages on TSA, however, the strain resembled the original isolate. At about passage 45, biological activity began to decline, and by passage 60 most biological activities were sharply diminished or undetectable. No recovery of biological activity was observed during a further 15 passages on TSA. Strains derived from the sixty-ninth passage of UT25, after passage on B-G for 5 subcultures, showed partial recovery of biological activity. Ten additional subcultures on B-G yielded strains which showed even higher biological activity. Fluorescent antibody staining confirmed that all strains studied were B. pertussis, and maintained reactive surface antigen(s), in spite of loss of agglutinability in specific antiserum.

Adenylyl Cyclases↗
PubMedDate not supplied

A prospective comparison of two types of tunneled hemodialysis catheters: the Ash Split versus the PermCath.

PURPOSE: In a prospective randomized study a standard dual-tip hemodialysis catheter (PermCath, Sherwood Medical, St. Louis, MO, USA) was compared with a newer split-lumen catheter (Ash Split, Medcomp, Harleysville, PA, USA). METHODS: Sixty-nine patients (42 men, 27 women; mean age 62 years) were randomized to receive either the Ash Split (AS) or the PermCath (PC) catheter. The catheters were inserted into the internal jugular vein. The primary outcome evaluated was blood flow measurements during the first six hemodialysis sessions. Secondary outcomes included: technical difficulties encountered at insertion, early complications and late complications requiring catheter removal or exchange. RESULTS: A total of 69 hemodialysis catheters, 33 AS and 36 PC, were successfully inserted in the internal jugular vein (right 60, left 9) of 69 patients. Mean blood flow during dialysis (Qb) was 270.75 ml/min and 261.86 ml/hr for the AS and PC groups respectively (p = 0.27). Mean duration of catheter use was 111.7 days (range 5.4-548.9 days) and 141.2 days (range 7.0-560.9 days) in the AS and PC groups respectively (p = 0.307). Catheter failures leading to removal or exchange occurred in 20 patients: 14 in the AS group and six in the PC group. Survival curves with censored endpoints (i.e., recovery, arteriovenous fistula formation, peritoneal dialysis and transplantation) showed significantly better outcome with PermCath catheters (p = 0.024). There was no significant difference in ease of insertion or early complication rates. CONCLUSION: The Ash Split catheter allows increased rates of blood flow during hemodialysis but this increase was not significant at the beginning (p = 0.21) or end (p = 0.27) of the first six hemodialysis sessions. The Ash Split catheter is more prone to minor complications, particularly dislodgment, than the PermCath catheter.

Blood Flow Velocity↗