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Biomedical subjects

P C Greig

Publications and source records attributed to P C Greig.

13 recordsLinked to original sources
PubMed1998

Maternal serum interleukin-6 concentration as a marker for impending preterm delivery.

OBJECTIVE: To determine whether serum interleukin-6 concentrations predict impending preterm delivery. METHODS: Blood samples were collected from 130 gravidas at 22-34 weeks' gestation. The study group consisted of 89 women evaluated for preterm contractions or premature rupture of membranes, and these women were compared with 41 outpatient controls without evidence of labor or infection, chosen by clinicians at the time of routine prenatal visits. Serum interleukin-6 concentrations were measured using a specific enzyme-linked immunosorbent assay kit. Analyses were by the Mann-Whitney U and the Kruskal-Wallis tests. RESULTS: All 41 control subjects had serum interleukin-6 concentrations less than 8 pg/mL. Sixteen of the 89 study patients had serum interleukin-6 concentrations greater than or equal to 8 pg/mL and 73 had values less than 8 pg/mL. When the serum interleukin-6 concentration was at least 8 pg/mL, the median interval from collection to delivery was significantly shorter than that among study and control subjects with serum interleukin-6 less than 8 pg/mL (5.5 versus 240 and 1801 hours, respectively; P < .001). The median gestational age at delivery was significantly lower when the serum interleukin-6 concentration was at least 8 pg/mL, compared with study and control subjects with serum interleukin-6 concentrations less than 8 pg/mL (29.6 versus 33.4 and 39.0 weeks, respectively; P < .001). In patients with preterm contractions, the interval from collection to delivery was significantly shorter when the serum interleukin-6 concentration was at least 8 pg/mL than when it was less than 8 pg/mL (3 versus 600 hours, P < .001). Similarly, the median gestational age at delivery was significantly lower when serum interleukin-6 was at least 8 pg/mL (29.0 versus 36.1 weeks, P < .001). CONCLUSION: Maternal serum interleukin-6 concentrations appear to be elevated in women destined to deliver prematurely. Measurement of this cytokine may prove useful in treating patients at high risk for preterm delivery.

Adult↗
PubMed1998

Umbilical venous D-dimer concentrations with and without labor.

OBJECTIVE: To determine if labor activates the fetal fibrinolytic system. METHODS: A total of 59 umbilical venous blood samples were collecting following vaginal delivery at term (n = 20), cesarean delivery following labor at term (n = 12), vaginal delivery before term (n = 18), and cesarean delivery without labor (n = 9). D-dimer concentrations, a sensitive marker of fibrinolysis, were measured by enzyme-linked immunosorbent assay, and compared between groups by Kruskel-Wallis and Mann Whitney U tests, with significance defined as P < .05. RESULTS: There were no significant differences in median D-dimer concentrations between newborns delivered vaginally or by cesarean after term labor or preterm labor. There were significant differences in median umbilical venous D-dimer concentrations in subjects delivered vaginally or by cesarean after term or preterm labor compared with term subjects without labor delivered by cesarean (427, 773, and 326 versus 87 ng/mL, P = .01). CONCLUSION: Elevation of umbilical plasma D-dimer concentrations in laboring patients suggests activation of fetal fibrinolysis before delivery.

Adult↗
PubMed1998

Amniotic fluid defensins: potential markers of subclinical intrauterine infection.

Human neutrophil peptides 1-3 (defensins) are granule constituents released from activated neutrophils. We hypothesized that amniotic fluid (AF) defensin levels are elevated in preterm labor (PTL) patients with subclinical intrauterine infection (IUI). AF samples were obtained from 203 pregnant patients with varying clinical characteristics. Defensin levels were measured by enzyme-linked immunosorbent assay. Median AF defensin levels were fourfold to 24-fold higher in patients with IUI than in preterm and term controls. Among patients with subclinical IUI, the degree of AF defensin elevation was greater in those with a positive AF culture. AF defensin levels increased exponentially with increasing severity of histologic chorioamnionitis. An AF defensin level of > 2,500 ng/mL identified 88% of patients with a positive AF culture, whereas a level of > 400 ng/mL identified 85% of all infected patients. AF defensin levels accurately identify patients with subclinical IUI, as defined by a positive AF culture or placental histology.

Amniotic Fluid↗
PubMed1997

Maternal serum interleukin-6 during pregnancy and during term and preterm labor.

OBJECTIVE: To determine the normal concentrations of maternal serum interleukin-6 during the second and third trimesters of pregnancy and the different stages of term and preterm labor, and to examine the clinical usefulness of measuring this cytokine in the serum of women in preterm labor to diagnose asymptomatic intrauterine infections. METHODS: Maternal serum interleukin-6 concentrations were measured cross-sectionally in 315 gravidas in their second and third trimesters and during term and preterm labor. Placentas from women who delivered preterm were examined for histologic chorioamnionitis. RESULTS: At term, women in labor had significantly elevated median maternal serum interleukin-6 concentrations compared with those at term not in labor (4.7 pg/mL versus 2.2 pg/mL, P < .001). Women admitted in preterm labor who delivered had significantly higher median interleukin-6 concentrations than did those in preterm labor who responded to tocolysis (9.3 pg/mL versus 1.9 pg/mL, P < .001). Women in preterm labor who delivered preterm with evidence of chorioamnionitis had significantly higher serum concentrations of interleukin-6 than did those in preterm labor who delivered in the absence of chorioamnionitis (15.9 pg/mL versus 4.6 pg/mL, P = .006). CONCLUSION: Compared with antepartum gravidas, those in term or preterm labor had significantly higher concentrations of maternal serum interleukin-6 concentrations; extremely elevated levels were found in patients whose preterm labor was associated with intrauterine infection.

Female↗
PubMed1997

Maternal serum granulocyte-colony stimulating factor in preterm birth with subclinical chorioamnionitis.

Preterm birth has been linked with intrauterine infection and inflammation. Serum and amniotic fluid markers of inflammation, such as interleukin-1 (IL-1), IL-6, and granulocyte-colony stimulating factor (G-CSF), have been associated with clinical chorioamnionitis and preterm delivery. As G-CSF regulates the production and maturation of neutrophils, we sought to determine if maternal serum G-CSF levels are elevated in patients with preterm birth with subclinical histologic chorioamnionitis. Maternal serum G-CSF levels were significantly different among five groups of women studied (P < .001, Kruskall-Wallis test), and were highest in subjects with preterm labor who delivered preterm (P < .05, Mann-Whitney U test). Among women with preterm labor who delivered preterm, maternal serum G-CSF levels were significantly higher if histologic chorioamnionitis was present than when histologic evidence of infection was not present (P = 0.04, Mann-Whitney U test). Intrauterine infection may cause a local inflammatory process and initiate preterm labor. This inflammatory response may include production of G-CSF, which would enter the circulation and stimulate the migration of neutrophils to the site of infection. Our data support this concept, as maternal serum G-CSF is elevated with subclinical infection in association with preterm birth.

Chorioamnionitis↗
PubMed1996

Maternal serum interleukin-6 concentrations in patients with preterm premature rupture of membranes and evidence of infection.

OBJECTIVE: Our purpose was to determine whether maternal serum interleukin-6 concentrations are elevated in patients with preterm premature rupture of membranes and intrauterine infection. STUDY DESIGN: By use of a sensitive enzyme-linked immunosorbent assay maternal serum interleukin-6 concentrations were measured in 110 samples from patients at 22 to 34 weeks gestation with the following conditions: nonlaboring, uninfected controls (n = 46), preterm premature rupture of membranes > 48 hours before delivery without infection (n = 27), preterm premature rupture of membranes 24 to 48 hours before delivery with subsequent clinical or histologic infection (n = 11), and preterm premature rupture of membranes < 24 hours before delivery with infection present by clinical or histologic criteria (n = 26). The Mann-Whitney U test was used for statistical analysis. RESULTS: Compared with that of nonlaboring controls, serum interleukin-6 was significantly higher in patients with preterm premature rupture of membranes < 24 hours before delivery with evidence of infection (17.2 vs 1.6 pg/ml, p < 0.0001). Patients with preterm premature rupture of membranes 24 to 48 hours before delivery who had infection had significantly higher interleukin-6 concentrations than did nonlaboring controls (3.6 vs 1.6 pg/ml, p = 0.006). There was no significant difference in interleukin-6 concentrations in nonlaboring controls compared with patients with preterm premature rupture of membranes when serum was obtained > 48 hours before delivery (1.6 vs 1.6 pg/ml, p = 0.90). A serum interleukin-6 level > or = 8 pg/ml yielded a sensitivity of 81%, a specificity of 99%, a positive predictive value of 96%, and a negative predictive value of 95% for identifying intrauterine infection in patients with preterm premature rupture of membranes on the day of delivery. CONCLUSIONS: Maternal serum interleukin-6 concentrations are elevated in patients with preterm premature rupture of membranes with clinical or histologic chorioamnionitis.

Delivery, Obstetric↗
PubMed1995

Amniotic fluid interleukin-10 concentrations increase through pregnancy and are elevated in patients with preterm labor associated with intrauterine infection.

OBJECTIVE: To better understand the role of the antiinflammatory cytokine interleukin-10 in preterm labor and infection, we evaluated the amniotic fluid interleukin-10 concentrations through pregnancy, in term, and in preterm labor. STUDY DESIGN: Amniotic fluid interleukin-10 levels were measured in 147 women throughout pregnancy including patients in the second trimester, patients at term with and without labor, and in patients in preterm labor with and without an intrauterine infection. We compared the amniotic fluid interleukin-10 concentrations among these five groups using the Mann-Whitney U test. RESULTS: Amniotic fluid interleukin-10 was detected in 70% to 91% of patients in each of the five study groups. Higher concentrations were found at term compared with the second trimester (p < 0.001) and concentrations were significantly greater in patients with preterm labor and intrauterine infection compared with those patients in preterm labor without infection (p < 0.001), patients at term in labor (p < 0.001), or patients at term not in labor (p < 0.001). When the patients in preterm labor with infection were analyzed by gestational age, those patients at < 30 weeks had significantly higher amniotic fluid concentrations of interleukin-10 (p = 0.014). CONCLUSIONS: Interleukin-10 was present in the amniotic fluid of the majority of pregnancies, with higher concentrations found at term compared with the second trimester. Intrauterine infection was associated with significantly increased concentrations, with even higher concentrations found in the very premature pregnancies. Interleukin-10 has a prominent yet undefined role in pregnancy and preterm labor complicated by intrauterine infection.

Amniotic Fluid↗
PubMed1994

Low amniotic fluid glucose levels are a specific but not a sensitive marker for subclinical intrauterine infections in patients in preterm labor with intact membranes.

OBJECTIVE: The purpose of this study was to evaluate the ability of a low amniotic fluid glucose level, as defined by previously published thresholds, to identify a subclinical intrauterine infection in women in preterm labor with intact membranes. STUDY DESIGN: Amniotic fluid glucose levels, amniotic fluid cultures, and placental histologic characteristics were determined in women with preterm labor (n = 55) and in preterm controls (n = 58). These amniotic fluid glucose levels were compared between women with and without intrauterine infection using the Mann-Whitney U test. The sensitivity, specificity, and positive and negative predictive values for the identification of an intrauterine infection were determined with four different previously published amniotic fluid glucose threshold levels and the threshold from receiver-operator characteristic curve analysis of the study data. RESULTS: The median amniotic fluid glucose level was significantly lower in patients with positive amniotic fluid cultures (intraamniotic infection group) but was not lower in the group of patients with only histologic chorioamnionitis (extra-amniotic infection group), compared with noninfected controls. The sensitivity of a low amniotic fluid glucose level to detect both types of intrauterine infection ranged from 41% to 55%, depending on the threshold used. The specificity of a low amniotic fluid glucose level to detect an intrauterine infection ranged from 94% to 100%, the positive predictive value ranged from 86% to 100%, and the negative predictive value ranged from 70% to 80% with the same thresholds. CONCLUSION: Low amniotic fluid glucose levels are a specific but not a sensitive marker for either intraamniotic or extra-amniotic intrauterine infections in patients with preterm labor.

Amniotic Fluid↗
PubMed1993

Maternal and fetal cardiovascular effects and placental transfer of the oxytocin antagonist atosiban in late-gestation pregnant sheep.

OBJECTIVES: Atosiban is a synthetic oxytocin antagonist that is currently undergoing dose-ranging clinical trials. To date, no data are available on the cardiovascular effects of combined oxytocin and vasopressin blockade during late pregnancy. Our aims were (1) to determine the effects of atosiban infusion on the maternal and fetal cardiovascular system and on uterine blood flow and (2) to determine the maternal pharmacokinetics and the rate of placental transfer of atosiban. STUDY DESIGN: Five chronically catheterized pregnant sheep were treated with a 2-hour infusion of atosiban (300 micrograms.min-1) at 116 to 126 days' gestation. Maternal and fetal blood pressure and heart rate and uterine blood flow were measured before and during the infusion. Maternal and fetal arterial blood samples were obtained throughout the experiment for measurement of plasma atosiban levels and blood gas values. RESULTS: No significant change in maternal cardiovascular parameters or uterine blood flow were observed. Similarly, no changes in fetal blood pressure and arterial blood gases were present during the infusion of the atosiban. Maternal plasma levels of atosiban reached a maximum of 585.2 +/- 82.2 (ng/ml mean +/- SD) at the end of the infusion and decreased biexponentially with a mean t1/2 alpha of 17 minutes and a mean t1/2 beta of 2.2 hours. Fetal plasma levels of atosiban were at or below the detection limit. CONCLUSION: Atosiban does not significantly affect maternal or fetal cardiovascular parameters when it is administered for 2 hours in late-pregnant sheep. Although significant levels were measured in maternal blood, negligible transfer to the fetus occurred.

Animals↗
PubMed1993

Amniotic fluid interleukin-6 levels correlate with histologic chorioamnionitis and amniotic fluid cultures in patients in premature labor with intact membranes.

OBJECTIVES: Our purpose was (1) to determine the frequency of intraamniotic and extraamniotic intrauterine infection in patients with premature labor and intact membranes and (2) to determine if intrauterine infection is associated with elevated amniotic fluid interleukin-6 levels. STUDY DESIGN: Amniocentesis was performed on 57 patients in preterm labor and 201 controls at various gestational ages without labor and at term with labor. The amniotic fluid was evaluated with gram stain, cultures, and an enzyme-linked immunosorbent assay specific for interleukin-6. Placentas from study patients (n = 52) and term controls (n = 120) were analyzed. RESULTS: The frequency of positive amniotic fluid cultures (intraamniotic intrauterine infection) was 10 of 57 (18%) in the preterm labor group and zero of 201 for controls. Histologic chorioamnionitis (extraamniotic intrauterine infection) was present in 21 of 24 (88%) of patients in preterm labor that failed tocolysis and 28 of 120 (23%) of term laboring controls. An amniotic fluid interleukin-6 level of > or = 600 pg/ml was 100% sensitive and 89% specific (positive predictive value 85%, negative predictive value 100%) for the identification of intrauterine infection. CONCLUSION: Interleukin-6 is a sensitive and specific marker for the identification of both intraamniotic and extraamniotic intrauterine infection in patients in preterm labor with intact membranes.

Adult↗
PubMed1992

The effect of presentation and mode of delivery on neonatal outcome in the second twin.

OBJECTIVE: The purpose of this study was to determine if cesarean delivery of the nonvertex second twin improved neonatal outcome. STUDY DESIGN: We examined the maternal and neonatal records from 457 sets of twins delivered from 1985 to 1990. We compared 1- and 5-minute Apgar scores, umbilical artery and vein blood pH values, duration of neonatal hospitalization, the incidence and length of ventilation, intraventricular hemorrhage, birth trauma, and mortality rate between vertex and nonvertex second twins delivered either vaginally or by cesarean section. RESULTS: The presentation and mode of delivery of the second twin was not associated with a significant difference in any of the outcome variables except for the 1-minute Apgar score, which was lower in the nonvertex group delivered vaginally. CONCLUSION: Our data do not support routine cesarean delivery for twins of any birth weight when the second twin is nonvertex.

Apgar Score↗
PubMedDate not supplied

Characterization of the inflammatory cytokines in the vagina during pregnancy and labor and with bacterial vaginosis.

OBJECTIVES: 1) To characterize the presence of interleukin-1 alpha (IL-1 alpha), interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-alpha) in the vagina during pregnancy and in labor; 2) to compare the vaginal levels of these inflammatory cytokines between laboring and nonlaboring patients; and 3) to compare the vaginal levels of these cytokines between women with and without bacterial vaginosis (BV). METHODS: Vaginal fluid was obtained by lavage from pregnant women with intact membranes at various gestational ages and during labor at term. These samples were analyzed for specific cytokine levels using standard enzyme-linked immunosorbent assay techniques. A Gram stain, wet mount, and pH were obtained from the vaginal fluid and were used to diagnose BV. The Mann-Whitney U test was used to evaluate the individual cytokine levels between groups, with P < .05 considered statistically significant. RESULTS: There was a wide range of vaginal cytokine levels found in our pregnant population (N = 72). Vaginal levels of IL-1 beta (median 1070 versus 245.7 pg/mL) and IL-6 (9.0 versus 0 pg/mL) were found to be significantly elevated in laboring patients as compared with nonlaboring patients (P = .005 and P = .002, respectively). There were no significant differences in the levels of IL-1 alpha and TNF-alpha between the laboring and nonlaboring women. Interleukin-1 beta was also found to be significantly elevated in the group of patients with BV (3364 versus 245.7 pg/mL; P = .01), particularly those who were nonlaboring (P = .003). In each individual patient, there was a wide variation in the levels of the four different cytokines. CONCLUSIONS: Measurable levels of the inflammatory cytokines IL-1 alpha, IL-1 beta, IL-6, and TNF-alpha were present in the vagina during pregnancy and labor. Vaginal levels of IL-1 beta and IL-6 were found to be significantly elevated in laboring patients as compared with nonlaboring patients. Vaginal levels of IL-1 beta were also significantly elevated in nonlaboring patients with BV.

Body Fluids↗