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Biomedical subjects

S E Davis

Publications and source records attributed to S E Davis.

10 recordsLinked to original sources
PubMed1991

Morbidity associated with prenatal disruption of the dividing membrane in twin gestations.

We report eight cases of intrauterine rupture of the dividing membranes in diamniotic twin gestations and the resulting perinatal morbidity and mortality. The poor outcomes associated with these intrauterine amniotic ruptures included fetal and neonatal death secondary to cord entanglement, preterm rupture of the membranes, preterm labor and delivery, and amniotic band syndrome. The overall perinatal mortality rate was 44% (seven of 16), and the mean gestational age at delivery was 29 weeks (range 22-34). Possible etiologies for this intrauterine diamniotic rupture include fetal trauma to the dividing membranes, amniocentesis, infection, and developmental disturbances. A new theory is examined to explain the surviving twin's morbidity associated with intrauterine death of the co-twin. This study suggests that intrauterine rupture of diamniotic twin membranes carries a perinatal mortality consistent with that of true monoamniotic gestations and that, in fact, this entity may be more common than previously thought. Finally, a suspected monoamniotic gestation cannot be ruled out by the historic presence of a dividing membrane on previous ultrasound examination.

Adolescent↗
PubMed1991

Etiologic factors associated with patellofemoral pain in runners.

The purpose of this study was to extend our knowledge of running related injuries by determining whether relationships exist between selected anthropometric, biomechanical, muscular strength and endurance, and training variables and runners afflicted with patellofemoral pain (PFP). Specifically, the objectives of this study were to examine differences in selected measures between a non-injured control group (C) of runners (N = 20) and a group of injured runners (INJ) diagnosed by an orthopedic surgeon as having PFP (N = 16). High speed photography, a force platform, and isokinetic dynamometry were used to determine rearfoot motion, ground reaction forces, and knee muscular strength and endurance. Stepwise discriminant function analyses were performed on the anthropometric, biomechanical, and muscular strength and endurance variables. Q angle was a significant discriminator (P less than 0.01) between the INJ and C groups. The muscular endurance data revealed several significant discriminators with the INJ subjects being weaker in knee extension endurance. Kinetic analysis revealed several significant discriminators whereas rearfoot movement variables were not good discriminators between the groups. The training data revealed that the INJ group ran significantly less (P less than 0.01) miles.wk-1 than the C group. Our results suggest that Q angle is a strong discriminator between runners afflicted with PFP and non-injured runners. In addition, several muscular endurance and kinetic variables may also be important components of the etiology of PFP.

Adolescent↗
PubMed1991

Perinatal outcome following improvement of abnormal umbilical artery velocimetry.

Umbilical artery velocimetry was investigated to determine whether abnormal flow patterns improved with bed rest and if the prognosis of the pregnancy was different in the improved groups. Abnormal flow waveform was defined as a systolic-diastolic ratio (S/D) above the 95th percentile of established normal values. One hundred twenty-eight women had abnormal waveforms. They were placed on bed rest in the left lateral position and monitored by biophysical profile and growth indices. Sixty-six subjects (51.5%) reverted to normal flow waveforms following bed rest, at a mean (+/- SD) interval of 4.5 +/- 1.5 weeks (range 3-10), and 62 (48.5%) exhibited persistent abnormal flow. None of the improved group exhibited fetal distress or perinatal mortality, whereas in the group with persistent abnormal flow, 15 (24%) experienced fetal distress and 13% experienced perinatal mortality. The diagnosis-to-delivery interval in the improved group was 63 +/- 14 days, versus 26 +/- 21 days in the unimproved group, and the mean gestational age at delivery was 37.3 +/- 2.0 versus 32.8 +/- 3.6 weeks, respectively (P less than .0001). We conclude that a subset of patients with abnormal Doppler velocimetry findings will improve on bed rest and have a better perinatal outcome, whereas persistence of abnormal flow defines a group of patients who are at risk for poor perinatal outcome and who require intensive monitoring and intervention.

Bed Rest↗
PubMed1990

Improving the outcome of cervical cerclage by sonographic follow-up.

A total of 39 patients with the diagnosis of cervical incompetence were followed up with cervical sonography after placement of prophylactic McDonald cerclage. During the first year of study, 3 out of 12 patients treated with prophylactic cerclage demonstrated funneling of the internal cervical os when examined with cervical sonography; all 3 had premature deliveries. During the last 3 years of the study, 8 of 27 patients treated with prophylactic cerclage demonstrated funneling. With active intervention, neonatal survival improved to 100%. Sonography aids in the management of patients with cervical incompetence and improves outcome even after placement of cervical cerclage.

Adult↗
PubMed1979

Dissociation of cortisol and adrenal androgen secretion in patients with secondary adrenal insufficiency.

Plasma cortisol, dehydroepiandrosterone (DHA), dehydroepiandrosterone sulfate (DHAS), and androstenedione (delta4-A) were measured by RIA during ACTH infusion in preadrenarchal children with constitutional short stature, normal adults, and patients with secondary adrenal insufficiency resulting from hypothalamic-pituitary disease or corticosteroid therapy. The plasma levels of all four steroids were decreased in patients with secondary adrenal insufficiency compared to normal adults, but the decrease in DHA and DHAS was considerably greater than that in cortisol and delta4-A, resulting in significant decreases in the plasma ratios of DHA to cortisol, DHAS to cortisol, DHA to delta4-A, and DHAS to delta4-A (P less than 0.00001). The decreased DHA and DHAS responses to ACTH persisted in one glucocorticoid-treated patient after glucocorticoid therapy was terminated and the cortisol response to ACTH had normalized. The data suggest that adrenal atrophy due to hypothalamic-pituitary disease or corticosteroid therapy is associated with a greater impairment in the secretion of the delta5 adrenal androgens DHA and DHAS than in the secretion of cortisol and delta4-A, and that the capacity to secrete cortisol and delta4-A recovers more rapidly than the capacity to secrete the delta5 adrenal androgens when corticosteroid therapy is withdrawn.

Adolescent↗
PubMed1975

A simple specific assay for estriol in maternal urine.

In medical centers with many high risk pregnancies, the ability to perform a large number of urinary estriol measurements is required. The analytical procedure should provide simplicity, specificity, and economy. A solid phase radioimmunoassay is presented which utilizes antibody generated against an estriol 16-glucuronide-bovine serum albumin conjugate. The assay allows analysis of the principal component of maternal urinary estriol without hydrolysis or purification, with adequate specificity and the capacity for processing large numbers of samples.

Animals↗