Reliability of the lung-to-head ratio as a predictor of outcome in fetuses with isolated left congenital diaphragmatic hernia at gestation outside 24-26 weeks.

OBJECTIVE: The purpose of this study was to investigate the relationship between lung-to-head ratio (LHR) and gestational age (GA) in fetuses with isolated left congenital diaphragmatic hernia and to determine the applicability and reliability of LHR to predict postnatal outcome beyond 24-26 weeks of gestation. STUDY DESIGN: The institutional review board approved this retrospective review of the University of California, San Francisco, Fetal Treatment Center database for cases with left congenital diaphragmatic hernia who were referred between March 1995 and June 2004. LHR was determined at the initial evaluation. One hundred seven live-born fetuses at 20-34 weeks of gestation (excluding cases that were lost to follow-up, with factors that potentially could influence the LHR measurement or postnatal outcome, or that were terminated electively). RESULTS: The median GA at LHR measurement was 25.6 weeks; the median LHR was 1.01; the median GA at birth was 37.7 weeks; and the overall survival rate was 59% (64/107). The median LHR of nonsurvivors was significantly lower than that of survivors, but neither GA at LHR measurement nor at delivery was significantly different between the groups. Multiple logistic regression analysis confirmed LHR to be an independent predictor of postnatal survival, and receiver-operator characteristic curve analysis demonstrated that an LHR of > or = 0.97 has the highest performance in predicting postnatal survival. When fetuses were grouped by GA at initial LHR measurement to determine reliability of LHR, specifically with respect to GA, in the 26-34 and 24-26 weeks of gestation groups, median LHR of survivors was significantly higher than that of nonsurvivors, and receiver-operator characteristic curve analysis confirmed LHR to be a reliable predictor of postnatal survival. However, for fetuses at 20-24 weeks of gestation, there was a trend toward a higher LHR in survivors, although this did not reach statistical significance. CONCLUSION: A significant positive linear relationship exists between LHR and GA at the time of measurement, such that LHR reliably predicts postnatal survival in fetuses with left congenital diaphragmatic hernia at 24-34 weeks of gestation and less reliable at 20-24 weeks. However, given the limitations of a retrospective, cross-sectional study, further prospective longitudinal studies that will investigate the change of LHR with GA and its association with fetal outcome are necessary.

Pre-emptive placement of a presealant for amniotic access.

OBJECTIVE: Amniotic access for fetal diagnosis and therapy can lead to membrane leaks, separation, and preterm premature rupture of membranes. Morbidity limits the beneficial effects of fetal intervention. We propose to examine a novel preventive "presealant" membrane puncture technique and evaluate it in vitro. STUDY DESIGN: Fetal membranes from normal term deliveries were fastened to a pressure controlled pump and punctured after presealant placement. Distinct bioadhesives were then compared for sealing efficacy by the measurement of leak pressures. Membranes were also evaluated for changes in tensile rupture strength after treatment. RESULTS: Preemptive sealing by 2 of the presealants achieved significantly higher leak pressures compared with control membranes (85 and 78, respectively, vs 27 cm of water; P < .05). One of the presealants worked effectively in a membrane-sealant-membrane interface (62 vs 30 cm of water; P < .05). All treated membranes, however, demonstrated diminished tensile rupture forces compared with control membranes (124 vs 170 g/cm2; P > .05). CONCLUSION: The application of a presealant is effective for the prevention of iatrogenic rupture in an in vitro model and may be beneficial for clinical application. Further studies with different bioadhesives are needed, given the limitations of the glues that are described in this study.

A multi-center study for birth defect monitoring systems in Korea.

The aim of this study was to establish a multi-center birth defects monitoring system to evaluate the prevalence and the serial occurrence of birth defects in Korea. Ten medical centers participated in this program. A trained nurse collected relevant records from delivery units and pediatric clinics in participating hospitals on a monthly basis. We observed 1,537 cases of birth defects among 86,622 deliveries, which included live births and stillbirths. The prevalence of birth defects was 1.8%, and the sex distribution of the birth defect cases was 55.2% male and 41.6% female. The highest proportion of birth defects was in the cardiovascular system (17.5%), followed by birth defects involving in the genitourinary system (15.6%). Chromosomal anomalies were detected 30.0 per 10,000 births. Of these chromosomal anomalies, Down syndrome was most frequently observed. This study led to an establishment of a multi-center active monitoring system for birth defects. To better understand the serial occurrence of birth defects in Korea, it is necessary to increase the number of participating hospitals and to launch on a nation-wide multi-center study.

Transvaginal ultrasonography for cervical assessment before induction of labor.

OBJECTIVE: To evaluate the value of ultrasonographic cervical assessment in predicting the outcome of labor induction and to compare its performance against the Bishop score. METHODS: The Bishop score was determined by digital examination, and transvaginal ultrasonography was performed in 105 women at 37 to 42 weeks' gestation scheduled for labor induction. Ultrasonographic parameters evaluated were cervical length, the presence of funneling, funnel width, and funnel length and were blinded to managing physicians. The primary outcome was the occurrence of active labor within 2 days (successful labor induction). The interval from the onset of induction to active labor (duration of induction) was the secondary outcome. Statistical analysis was performed by the chi2 test, Wilcoxon rank sum test, Pearson correlation, receiver operating characteristic curves, logistic regression, Cox proportional hazards model, and generalized Wilcoxon test for survival data. RESULTS: Induction of labor was successful in 93 women (89%). The area under the receiver operating characteristic curve for cervical length was greater than that of the Bishop score in predicting a successful labor induction (z = 2.18; P < .05). A cervical length of 3.0 cm or less had sensitivity of 75% (70 of 93) and specificity of 83% (10 of 12). Multiple logistic regression analysis showed a significant relationship between successful labor induction and cervical length but not the Bishop score (odds ratio = 0.24; 95% confidence interval, 0.096-0.59; P = .002). Only parity and cervical length had a significantly independent relationship with the duration of induction. CONCLUSIONS: Cervical length measured by transvaginal ultrasonography is a useful and independent predictor of successful labor induction and the duration of induction and provides better predictability of successful labor induction than the Bishop score does.

Multiple courses of antenatal corticosteroid therapy in patients with preterm premature rupture of membranes.

OBJECTIVE: This study was performed to determine the benefits and risks of multiple courses of corticosteroids in patients with preterm premature rupture of membranes (PPROM). METHOD: We retrospectively evaluated the pregnancy and neonatal outcomes of women with singleton pregnancies, who were admitted at 24-32 weeks of gestation due to PPROM. Patients were categorized into 3 groups according to antenatal corticosteoid exposure: (1) a non-user group, (2) a single-course group, and (3) a multiple-course group. RESULT: A total of 170 patients were included in the study, with 50 in the non-use group, 76 in the single-course group, and 44 in the multiple-course group. Univariate analyses showed that clinical chorioamnionitis occurred with highest incidence in multiple-course group (chi2=6.20, p<0.05) and the incidence of neonatal respiratory distress syndrome (RDS) was lowest in the multiple-course group (chi2=10.0, p<0.01). Multiple logistic regression analyses showed that multiple courses of corticosteroids were independently associated with clinical chorioamnionitis (odds ratio=13.15, p<0.05) whereas no significant association was found between RDS and multiple-course corticosteroids after adjusting for confounding variables (odds ratio=0.28, p=0.06). CONCLUSION: Multiple courses of antenatal corticosteroid therapy were found to be associated with an increased risk of clinical chorioamnionitis and seemed not to reduce the incidence of RDS and other neonatal morbidities in patients with PPROM.

Ultrasound evaluation of normal and abnormal fetuses: comparison of conventional, tissue harmonic, and pulse-inversion harmonic imaging techniques.

OBJECTIVE: To determine the usefulness of tissue harmonic imaging (THI) and pulse-inversion harmonic imaging (PIHI) in the evaluation of normal and abnormal fetuses. MATERIALS AND METHODS: Forty-one pregnant women who bore a total of 31 normal and ten abnormal fetuses underwent conventional ultrasonography (CUS), and then THI and PIHI. US images of six organ systems, namely the brain, spine, heart, abdomen, extremities and face were compared between the three techniques in terms of overall conspicuity and the definition of borders and internal structures. RESULTS: For the brain, heart, abdomen and face, overall conspicuity at THI and PIHI was significantly better than at CUS (p < 0.05). There was, though, no significant difference between THI and PIHI. Affected organs in abnormal fetuses were more clearly depicted at THI and PIHI than at CUS. CONCLUSION: Both THI and PIHI appear to be superior to CUS for the evaluation of normal or abnormal structures, particularly the brain, heart, abdomen and face.

Rh-catalyzed one-pot and practical transformation of aldoximes to amides.

Wilkinson's complex has been found to catalyze the one-pot transformation of aldoximes to the corresponding amides with high selectivity and efficiency under essentially neutral conditions.

Regulation of connexin 43 by nitric oxide in primary uterine myocytes from term pregnant women.

OBJECTIVE: Our purpose was to test the hypothesis that nitric oxide signals regulate the expression of the gap-junction protein connexin 43 in primary uterine myocytes from pregnant women at term. STUDY DESIGN: Northern analysis and immunoblotting were used to determine the expression of connexin 43 in myocytes cultured in the presence of the nitric oxide donors S -nitroso-N -acetyl-penicillamine (SNAP) (100 micromol/L) and (Z)-1-[2-(2-aminoethyl)-N -(2-ammonioethyl)amino]diazen-1-ium-1,2-diolate diethylenetriamine (NOC-18) (100 micromol/L). We also tested the effect of the NO stimulants 8-bromo-cyclic adenosine 3',5'-monophosphate (cAMP) (100 micromol/L) and 8-bromo-cyclic guanosine 3',5'-monophosphate (cGMP) (200 micromol/L), and the nitric oxide synthase inhibitors N -nitro-L-arginine methyl ester (NAME) (100 micromol/L) and L -N (1-iminoethyl)lysine (NIL) (50 micromol/L). RESULTS: Nitric oxide and 8-bromo-cAMP reduced the level of connexin 43 expression, and 8-bromo-cGMP had no effect. In contrast, NIL, but not NAME, increased the levels of connexin 43 protein without affecting the level of connexin 43 messenger RNA. With immunoblotting, expression of inducible nitric oxide synthase was not detected in these cells. CONCLUSION: Nitric oxide down-regulates the expression of connexin 43 in cultured human myocytes. We speculate that this effect may decrease the efficacy of intermyocyte signaling and thus contribute to uterine quiescence during human pregnancy.

Differential expressions of Fas and Fas ligand in human placenta.

To investigate the expressions of Fas and Fas ligand (FasL) in human placenta, we studied the expressions of Fas and FasL in placenta with RT-PCR, immunoblotting and immunostaining. We observed amplified products of Fas and FasL transcripts, the band of Fas (52 kDa) and multiple bands of FasL (42-52 kDa) in placenta. Fas and FasL localized mainly on fetal vessels and on syncytiotrophoblasts respectively. The differential distribution of Fas and FasL in human placenta may reflect intrinsic expressions of them by trophoblasts during differentiation. The increased expression of Fas in trophoblasts may promote apoptosis of placenta in pathologic condition such as preeclampsia.