Biomedical subjects

S Campion

Publications and source records attributed to S Campion.

5 recordsLinked to original sources

PubMed1991

Developmental expression of the embryonic chicken brain DNA polymerase alpha and its binding with monoclonal antibodies against human KB cell DNA polymerase alpha.

Changes in DNA polymerase alpha activity accompanying tissue development have been well established in several systems. In most cases, DNA polymerase alpha activity decreases with development. Here, we report observed changes in DNA polymerase alpha activity throughout embryonic chicken brain (ECB) development. The level of DNA polymerase alpha activity was found to gradually decrease by 60% (2.3 to 0.8 nmol of [3H]dCMP incorporated/mg protein/h) between 9- and 19-day-old ECB. An enzyme-linked immunosorbent assay of DNA polymerase alpha utilizing monoclonal antibody SJK 237-71 (human KB cell DNA pol-alpha binder) also demonstrated a gradual decrease (up to 60%) of antigen over this same range of development. Analysis of DNA polymerase alpha from 11- and 19-day-old ECB by a 10 to 30% glycerol density gradient revealed a high molecular weight peak sedimenting near catalase (11.3 S) with activity at the 11th day being approximately 3-fold greater than activity at the 19th day. A Western immunoblot analysis utilizing monoclonal antibody SJK 237-71 (against human KB cell DNA polymerase alpha) showed a decrease in DNA polymerase alpha from 186 kilodaltons in 9- and 11-day ECB cell-free extracts to 120 kilodaltons in extracts from 13- to 19-day ECB. The conversion of DNA polymerase alpha from a higher to a lower molecular weight form may be a regulatory mechanism in eukaryotic DNA replication.

Animals↗

PubMed1990

Ambulatory tocodynamometry data interpretation: evaluating variability and reliability.

The inter- and intra-observer variabilities of interpretation of uterine activity monitoring data were determined from the interpretations of 20 ambulatory tocodynamometry records by nine physicians and nurses. The presence of contractions lasting less than 40 seconds or presenting at a frequency of fewer than four per hour was associated with significantly reduced accuracy of interpretation. The reliability was 70% with one observer, 82% with two observers, and 88% with three observers. Higher variability and lower reliability values were obtained for interpretation of low-amplitude, high-frequency contractions. Understanding the limitation of uterine activity data interpretation should help in the clinical management of monitored patients.

Ambulatory Care↗

PubMed1989

The influence of fetal number on antepartum uterine activity.

Home uterine activity monitoring was performed by 54 women with singleton, 30 with twin, and 34 with triplet gestations. Data were analyzed to determine the relationship between antepartum uterine activity, preterm labor, and fetal number. Preterm labor in singleton and twin gestations was preceded by significant increases in pre-labor contraction frequency (P less than .01). However, in triplets, preterm labor was not preceded by increased pre-labor contractions. Triplet and twin gestations with term labor were associated with higher baseline contraction frequencies than were high-risk singleton gestations with term labor (P less than .05). Fetal number had no impact on pre-labor contraction intensity, although triplet gestations had a significantly greater proportion of uterine activity occupied by low-amplitude, high-frequency contractility.

Female↗

PubMed1988

Intermittent weekly contraction monitoring to predict preterm labor in low-risk women: a blinded study.

To assess the predictive value of uterine activity as a marker for subsequent preterm labor, 139 black, inner city women were monitored at least three times for 1 hour between 28-32 weeks' gestation using a portable tocodynamometer. All had singleton gestations and gave no previous history of preterm labor or delivery. They were monitored between 8 and 10 AM while sitting in the clinic waiting area. Uterine activity records, numbered randomly, were transmitted by telephone to a site remote from the hospital. No one having any clinical contact with the participants saw or received feedback regarding the contraction data. Tocodynamometry records were then mailed to another center where they were read by one investigator blinded to all clinical information. The mean contraction frequency during the single hour of weekly testing was significantly greater for the 16 women who developed preterm labor than for women who delivered at term at each point between weeks 28-32. Using greater than six contractions per hour on at least one occasion between 28-32 weeks' gestation as a predictor would have identified 12 of 16 women (sensitivity 75%) who subsequently developed preterm labor. This contraction frequency was noted in 26 of 123 women (21%) who labored at term (specificity 79%; P = .0003).

Female↗

PubMed1987

Antepartum ambulatory tocodynamometry: the significance of low-amplitude, high-frequency contractions.

The clinical significance of low-amplitude, high-frequency contractions was examined during pregnancy in 142 women who underwent daily ambulatory tocodynamometry between 23-36 weeks' gestation. The results indicate that patients destined to develop preterm labor had this contractility pattern significantly more often than did their counterparts who delivered at term (13.5 versus 9.2%; P less than .01). Parity and gestational age had no effect on the occurrence of low-amplitude, high-frequency contractility, but this pattern was also significantly more prevalent in the presence of multifetal gestations, independent of the occurrence of preterm labor. The institution of tocolytic therapy was accompanied by a 50% decrease in the proportion of time occupied by low-amplitude, high-frequency contractions. Although this contraction pattern occurred significantly more often among patients who later developed preterm labor, calculations of its predictive values, specificity, and sensitivity indicate that its presence has relatively limited clinical significance.

Female↗