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Mock DM, Quirk JG, Mock NI. Am J Clin Nutr 2002;75:295-299. BACKGROUND: Biotin deficiency is teratogenic in several mammalian species. Approximately 50% of pregnant women have an abnormally increased urinary [...]

Introduction: During labor, fetal heart rate (FHR) and uterine activity (UA) can be continuously monitored using Cardiotocography (CTG). This is the most widely adopted approach for electronic fetal monitoring in hospitals. Both FHR and UA recordings are evaluated by obstetricians for assessing fetal well-being. Due to the complex and noisy nature of these recordings, the evaluation by obstetricians suffers from high interobserver and intraobserver variability. Machine learning is a field that has seen unprecedented advances in the past two decades and many efforts have been made in computerized analysis of CTG using machine learning methods. However, in the literature, the focus is often only on FHR signals unlike in evaluations performed by obstetricians where the UA signals are also taken into account. Methods: Machine learning is a field that has seen unprecedented advances in the past two decades and many efforts have been made in computerized analysis of CTG using machine learning methods. However, in the literature, the focus is often only on FHR signals unlike in evaluations performed by obstetricians where the UA signals are also taken into account. In this paper, we propose to model intrapartum CTG recordings from a dynamical system perspective using empirical dynamic modeling with Gaussian processes, which is a Bayesian nonparametric approach for estimation of functions. Results and Discussion: In the context of our paper, Gaussian processes are capable for simultaneous estimation of the dimensionality of attractor manifolds and reconstructing of attractor manifolds from time series data. This capacity of Gaussian processes allows for revealing causal relationships between the studied time series. Experimental results on real CTG recordings show that FHR and UA signals are causally related. More importantly, this causal relationship and estimated attractor manifolds can be exploited for several important applications in computerized analysis of CTG recordings including estimating missing FHR samples, recovering burst errors in FHR tracings and characterizing the interactions between FHR and UA signals., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Feng, Heiselman, Quirk and Djurić.)

Low umbilical artery pH is a marker for neonatal acidosis and is associated with an increased risk for neonatal complications. The phase-rectified signal averaging (PRSA) features have demonstrated superior discriminatory or diagnostic ability and good interpretability in many biomedical applications including fetal heart rate analysis. However, the performance of PRSA method is sensitive to values of the selected parameters which are usually either chosen based on a grid search or empirically in the literature. In this paper, we examine PRSA method through the lens of dynamical systems theory and reveal the intrinsic connection between state space reconstruction and PRSA. From this perspective, we then introduce a new feature that can better characterize dynamical systems comparing with PRSA. Our experimental results on an open-access intrapartum Cardiotocography database demonstrate that the proposed feature outperforms state-of-the-art PRSA features in pH-based fetal heart rate analysis.

The computer-aided interpretation of fetal heart rate (FHR) and uterine contraction (UC) has not been developed well enough for wide use in delivery rooms. The main challenges still lie in the lack of unclear and nonstandard labels for cardiotocography (CTG) recordings, and the timely prediction of fetal state during monitoring. Rather than traditional supervised approaches to FHR classification, this paper demonstrates a way to understand the UC-dependent FHR responses in an unsupervised manner. In this work, we provide a complete method for FHR-UC segment clustering and analysis via the Gaussian process latent variable model, and density-based spatial clustering. We map the UC-dependent FHR segments into a space with a visual dimension and propose a trajectory-based FHR interpretation method. Three metrics of FHR trajectory are defined and an open-access CTG database is used for testing the proposed method.

During the process of childbirth, fetal distress caused by hypoxia can lead to various abnormalities. Cardiotocography (CTG), which consists of continuous recording of the fetal heart rate (FHR) and uterine contractions (UC), is routinely used for classifying the fetuses as hypoxic or non-hypoxic. In practice, we face highly imbalanced data, where the hypoxic fetuses are significantly underrepresented. We propose to address this problem by boost ensemble learning, where for learning, we use the distribution of classification error over the dataset. We then iteratively select the most informative majority data samples according to this distribution. In our work, in addition to addressing the imbalanced problem, we also experimented with features that are not commonly used in obstetrics. We extracted a large number of statistical features of fetal heart tracings and uterine activity signals and used only the most informative ones. For classification, we implemented several methods: Random Forest, AdaBoost, k -Nearest Neighbors, Support Vector Machine, and Decision Trees. The paper provides a comparison in the performance of these methods on fetal heart rate tracings available from a public database. Our results show that most applied methods improved their performances considerably when boost ensemble was used.

Detection of anomalies in time series is still a challenging problem. In this paper, we provide a new approach to unsupervised detection of anomalies in time series based on the concept of phase space reconstruction and manifolds. We propose a rotation-insensitive metric for quantifying the similarity of manifolds and a method that uses it for estimating the probability of an outlier. The proposed method does not rely on any features and can be used for signals with variable lengths. We tested it on both synthetic signals and real fetal heart rate tracings. The method has promising performance and can be used for interpreting the severity of fetal asphyxia.

Classification with imbalanced data is a common and challenging problem in many practical machine learning problems. Ensemble learning is a popular solution where the results from multiple base classifiers are synthesized to reduce the effect of a possibly skewed distribution of the training set. In this paper, binary classifiers based on Gaussian processes are chosen as bases for inferring the predictive distributions of test latent variables. We apply a Gaussian process latent variable model where the outputs of the Gaussian processes are used for making the final decision. The tests of the new method in both synthetic and real data sets show improved performance over standard approaches.

Identifying uterine contractions with the aid of machine learning methods is necessary vis-á-vis their use in combination with fetal heart rates and other clinical data for the assessment of a fetus wellbeing. In this paper, we study contraction identification by processing noisy signals due to uterine activities. We propose a complete four-step method where we address the imbalanced classification problem with an ensemble Gaussian process classifier, where the Gaussian process latent variable model is used as a decision-maker. The results of both simulation and real data show promising performance compared to existing methods.

Convergent cross mapping (CCM) is designed for causal discovery in coupled time series, where Granger causality may not be applicable because of a separability assumption. However, CCM is not robust to observation noise which limits its applicability on signals that are known to be noisy. Moreover, the parameters for state space reconstruction need to be selected using grid search methods. In this paper, we propose a novel improved version of CCM using Gaussian processes for discovery of causality from noisy time series. Specifically, we adopt the concept of CCM and carry out the key steps using Gaussian processes within a non-parametric Bayesian probabilistic framework in a principled manner. The proposed approach is first validated on simulated data, and then used for understanding the interaction between fetal heart rate and uterine activity in the last two hours before delivery and of interest in obstetrics. Our results indicate that uterine activity affects the fetal heart rate, which agrees with recent clinical studies.

During labor, fetal heart rate (FHR) is monitored externally using Doppler ultrasound. This is done continuously, but for various reasons (e.g., fetal or maternal movements) the system does not record any samples for varying periods of time. In many settings, it would be quite beneficial to estimate the missing samples. In this paper, we propose a (deep) Gaussian process-based approach for estimation of consecutively missing samples in FHR recordings. The method relies on similarities in the state space and on exploiting the concept of attractor manifolds. The proposed approach was tested on a short segment of real FHR recordings. The experimental results indicate that the proposed approach is able to provide more reliable results in comparison to several interpolation methods that are commonly applied for processing of FHR signals.

During labor, fetal heart rate (FHR) and uterine activity (UA) are continuously monitored with Cardiotocography (CTG). The FHR and UA signals are visually inspected by obstetricians to assess the fetal well-being. However, due to the subjectivity of the visual inspection, the evaluations of CTG recordings performed by obstetricians have high inter- and intra-variability. The computerized analysis of FHR relies on features either hand-crafted by experts or automatically learned by machine learning methods. However, the popular interpretable FHR features, in general, have low correlation with the pH value of the umbilical cord blood at birth, which is the current gold standard for labeling FHRs in the computerized analysis of FHRs. The features found by machine learning methods, by contrast, usually have limited interpretability. In this paper, in a follow up of our previous work on FHR analysis using Gaussian processes (GPs), we explore the possibility of using the hyperparameters of GPs as interpretable features. Our results indicate that some GP features achieve high correlation with the pH values, while at the same time they are not highly correlated with other popular features.

Convergent cross mapping (CCM) is a state space reconstruction (SSR)-based method designed for causal discovery in coupled time series, where Granger causality may not be applicable due to a separability assumption. However, CCM requires a large number of observations and is not robust to observation noise which limits its applicability. Moreover, in CCM and its variants, the SSR step is mostly implemented with delay embedding where the parameters for reconstruction usually need to be selected using grid search-based methods. In this paper, we propose a Bayesian version of CCM using deep Gaussian processes (DGPs), which are naturally connected with deep neural networks. In particular, we adopt the framework of SSR-based causal discovery and carry out the key steps using DGPs within a non-parametric Bayesian probabilistic framework in a principled manner. The proposed approach is first validated on simulated data and then tested on data used in obstetrics for monitoring the well-being of fetuses, i.e., fetal heart rate (FHR) and uterine activity (UA) signals in the last two hours before delivery. Our results indicate that UA affects the FHR, which agrees with recent clinical studies.

In this paper, we propose a novel and simple method for discovery of Granger causality from noisy time series using Gaussian processes. More specifically, we adopt the concept of Granger causality, but instead of using autoregressive models for establishing it, we work with Gaussian processes. We show that information about the Granger causality is encoded in the hyper-parameters of the used Gaussian processes. The proposed approach is first validated on simulated data, and then used for understanding the interaction between fetal heart rate and uterine activity in the last two hours before delivery and of interest in obstetrics. Our results indicate that uterine activity affects fetal heart rate, which agrees with recent clinical studies.

Objective: To compare the rapid bedside test for placental α microglobulin-1 with the instrumented fetal fibronectin test for prediction of imminent spontaneous preterm delivery among women with symptoms of preterm labor., Methods: We conducted a prospective observational study on pregnant women with signs or symptoms suggestive of preterm labor between 24 and 35 weeks of gestation with intact membranes and cervical dilatation less than 3 cm. Participants were prospectively enrolled at 15 U.S. academic and community centers. Placental α microglobulin-1 samples did not require a speculum examination. Health care providers were blinded to placental α microglobulin-1 results. Fetal fibronectin samples were collected through speculum examination per manufacturer requirements and sent to a certified laboratory for testing using a cutoff of 50 ng/mL. The coprimary endpoints were positive predictive value (PPV) superiority and negative predictive value (NPV) noninferiority of placental α microglobulin-1 compared with fetal fibronectin for the prediction of spontaneous preterm birth within 7 days and within 14 days., Results: Of 796 women included in the study cohort, 711 (89.3%) had both placental α microglobulin-1 and fetal fibronectin results and valid delivery outcomes available for analysis. The overall rate of preterm birth was 2.4% (17/711) within 7 days of testing and 4.2% (30/711) within 14 days of testing with respective rates of spontaneous preterm birth of 1.3% (9/703) and 2.9% (20/701). Fetal fibronectin was detected in 15.5% (110/711), and placental α microglobulin-1 was detected in 2.4% (17/711). The PPVs for spontaneous preterm delivery within 7 days or less among singleton gestations (n=13) for placental α microglobulin-1 and fetal fibronectin were 23.1% (3/13) and 4.3% (4/94), respectively (P<.025 for superiority). The NPVs were 99.5% (619/622) and 99.6% (539/541) for placental α microglobulin-1 and fetal fibronectin, respectively (P<.001 for noninferiority)., Conclusion: Although placental α microglobulin-1 performed the same as fetal fibronectin in ruling out spontaneous preterm delivery among symptomatic women, it demonstrated statistical superiority in predicting it.

In this paper, we propose an application of non-parametric Bayesian (NPB) models for classification of fetal heart rate (FHR) recordings. More specifically, we propose models that are used to differentiate between FHR recordings that are from fetuses with or without adverse outcomes. In our work, we rely on models based on hierarchical Dirichlet processes (HDP) and the Chinese restaurant process with finite capacity (CRFC). Two mixture models were inferred from real recordings, one that represents healthy and another, non-healthy fetuses. The models were then used to classify new recordings and provide the probability of the fetus being healthy. First, we compared the classification performance of the HDP models with that of support vector machines on real data and concluded that the HDP models achieved better performance. Then we demonstrated the use of mixture models based on CRFC for dynamic classification of the performance of (FHR) recordings in a real-time setting.

In this paper, we propose an application of non-parametric Bayesian (NPB) models to classification of fetal heart rate recordings. More specifically, the models are used to discriminate between fetal heart rate recordings that belong to fetuses that may have adverse asphyxia outcomes and those that are considered normal. In our work we rely on models based on hierarchical Dirichlet processes. Two mixture models were inferred from recordings that represent healthy and unhealthy fetuses, respectively. The models were then used to classify new recordings. We compared the classification performance of the NPB models with that of support vector machines on real data and concluded that the NPB models achieved better performance.

This paper presents novel methods for classification of fetal heart rate (FHR) signals into categories that are meaningful for clinical implementation. They are based on generative models (GMs) and Bayesian theory. Instead of using scalar features that summarize information obtained from long-duration data, the models allow for explicit use of feature sequences derived from local patterns of FHR evolution. We compare our methods with a deterministic expert system for classification and with a support vector machine approach that relies on system-identification and heart rate variability features. We tested the classifiers on 83 retrospectively collected FHR records, with the gold-standard true diagnosis defined using umbilical cord pH values. We found that our methods consistently performed as well as or better than these, suggesting that the use of GMs and the Bayesian paradigm can bring significant improvement to automatic FHR classification approaches.

The neonatal intensive care unit (NICU) is a high-stress environment for both families and health care providers that can sometimes make appropriate medical decisions challenging. We present a review article of non-medical barriers to effective decision making in the NICU, including: miscommunication, mixed messages, denial, comparative social and cultural influences, and the possible influence of perceived legal issues and family reliance on information from the Internet. As examples of these barriers, we describe and discuss two cases that occurred simultaneously in the same NICU where decisions were influenced by social and cultural differences that were misunderstood by both medical staff and patients' families. The resulting stress and emotional discomfort created an environment with sub-optimal relationships between patients' families and health care providers. We provide background on the sources of conflict in these particular cases. We also offer suggestions for possible amelioration of similar conflicts with the twin goals of facilitating compassionate decision making in NICU settings and promoting enhanced well-being of both families and providers.

We present the case of a 36-year-old woman who has experienced three lost pregnancies; during the most recent loss, a full term pregnancy, she almost died from complications of placental abruption. She is now completing the 34th week of gestation and is experiencing symptoms similar to those under which she lost the previous pregnancy. Despite a lack of specific medical indications, the patient and her husband firmly but politely request that the attending obstetrician/perinatologist perform an immediate cesarean section in order to alleviate the couple's anxiety about possibly never having a family. Discussing the case are an experienced perinatologist, a neonatologist, a regional perinatal center coordinator, and a clinical ethicist.

We present preliminary results on the use of Bayesian-network (BN) structure learning algorithms for deciphering dependencies from amongst different fetal heart rate (FHR) features collected from a real database. We used a greedy search-and-score procedure known as the K2 algorithm for the estimation of the BN structure. The database consists of a collection of discrete-valued features quantifying presence of morphological changes as prescribed by expert guidelines (updated by the National Institute of Child Health and Human Development (NICHD)) and implemented as rule-based programs. We compare the results of structure learning to the expert-guided structure and use decision functions for classification using posterior probabilities. It was found that the BN estimated from structure learning algorithms had comparable classification performance, but fewer edges, leading to more efficient characterization of conditional probability tables (CPD's). Moreover, structure learning algorithms offer a method of learning novel correlations between FHR features that may be exploited for automatic categorization.

Trauma during pregnancy has presented very unique challenges over the centuries. From the first report of Ambrose Pare of a gunshot wound to the uterus in the 1600s to the present, there have existed controversies and inconsistencies in diagnosis, management, prognostics, and outcome. Anxiety is heightened by the addition of another, smaller patient. Trauma affects 7% of all pregnancies and requires admission in 4 of 1000 pregnancies. The incidence increases with advancing gestational age. Just over half of trauma during pregnancy occurs in the third trimester. Motor vehicle crashes comprise 50% of these traumas, and falls and assaults account for 22% each. These data were considered to be underestimates because many injured pregnant patients are not seen at trauma centers. Trauma during pregnancy is the leading cause of nonobstetric death and has an overall 6% to 7% maternal mortality. Fetal mortality has been quoted as high as 61% in major trauma and 80% if maternal shock is present. The anatomy and physiology of pregnancy make diagnosis and treatment difficult.

Objective: To measure and compare pulse pressure in early pregnancy between parturients who subsequently did or did not develop preeclampsia., Study Design: Retrospective chart review of 44 parturients with preeclampsia and 187 controls without. The groups were compared for blood pressure indices before 15 weeks' gestation and other maternal variables., Results: The preeclampsia group had a higher proportion of African Americans (23% vs. 9.6%, p = 0.005) and higher body mass index (26.2 +/- 7.1 SD vs. 24.0 +/- 4.9 kg/m2, p = 0.03). Before 15 weeks' gestation, women who later developed preeclampsia had higher systolic (114.3 +/- 11.6 vs. 107 +/- 12 mm Hg, p = 0.001), mean arterial (83.7 +/- 8.8 vs. 79.6 +/- 7.6 mm Hg, p = 0.002) and pulse (45.8 +/- 7.7 vs. 42.4 +/- 8.3 mm Hg, p = 0.001) pressure. On multivariable logistic regression analysis, only African American race (OR 3.1; 95% CI 1.13, 8.40; p = 0.028), and pulse pressure (OR 1.05; 95% CI 1.01, 1.1; p = 0.014) were independently associated with the development of preeclampsia., Conclusion: Primiparous women who later develop preeclampsia have an elevation in pulse, systolic and mean arterial pressure before 15 weeks.

Objective: To determine the effect of the genetic counselor on the acceptance of genetic amniocentesis., Methods: We studied women with singleton pregnancies who would be at least 35 years of age at the estimated date of delivery without fetal structural anomalies or family history of chromosomal abnormalities. The acceptance rate of genetic amniocentesis among women evaluated by each counselor was compared with the average acceptance rate for our population. Chi-square test, Fisher exact test and ANOVA were used for analysis., Results: Of the 2,180 women met our inclusion criteria, 1,719 (78.9%) accepted genetic amniocentesis. The maternal age at estimated date of delivery, the proportion of women who conceived by in vitro fertilization, and the proportion with history of miscarriage were similar among women evaluated by each of the six genetic counselors. However, the acceptance rate of genetic amniocentesis was significantly lower in women evaluated by counselor C [115/170 (67.6%), P=0.001] and significantly higher in the group evaluated by counselor D [138/154 (89.6%), P=0.002] compared with the overall study population rate [1719/2180 (78.9%)]. The acceptance rate of 80.4% (210/261, P=0.52), 75.6 % (232/307, P=0.23), 80.9% (443/547, P=0.30] and 78.4% (581/741, P=0.83) for Counselors A, B, E and F respectively did not differ from the overall study population rate., Conclusions: Considerable variation exists in the acceptance rate of genetic amniocentesis among women based on the genetic counselor.

Objective: To determine whether the fetal admission test is predictive of intrapartum complications., Methods: We studied the fetal heart rate tracings of women in spontaneous labor at 37-42 weeks' gestation from 1 November 2001 to 31 March 2002. The study population was subdivided based on reactivity defined as > or = 15 beats/min for > or = 15 s, reactivity redefined as > or = 10 beats/min for > or = 10 s, variability, presence of late and/or variable decelerations, and reassuring fetal admission test; and compared for various labor outcome variables. Student's t test, the chi2 test and Fisher's exact test were used for analysis., Results: A total of 426 women met our inclusion criteria. There were no differences between groups when compared for maternal age, parity, gestational age, birth weight, labor analgesia and length of labor. Irrespective of the definition of reactivity, women with a non-reactive fetal admission test were more likely to be delivered by Cesarean section, to have fetal distress resulting in Cesarean section and to have a longer neonatal hospital stay. In addition, redefining reactivity improved the specificity, positive and negative predictive values, accuracy, relative risk and likelihood ratio with regard to development of fetal distress. Similar results were obtained when variability and decelerations were used as criteria for comparisons., Conclusion: The fetal admission test is useful in predicting the absence of intrapartum fetal distress irrespective of the criterion used for evaluation. Redefined reactivity appears to be most predictive of intrapartum fetal distress.

Objective: To determine whether in utero exposure to magnesium sulfate was associated with increased neonatal morbidity and mortality among premature neonates, and secondarily to determine the relationship, if any, between duration of magnesium sulfate exposure and neonatal morbidity and mortality., Methods: We studied 401 neonates at our institution who were born between 23 and 34 weeks' gestation following preterm labor or preterm premature rupture of membranes. The population was stratified by exposure to magnesium sulfate and compared by various neonatal outcome variables. Similarly, the magnesium-exposed population was stratified by duration of exposure and compared for various neonatal outcome variables. Student's t test, chi2 test, Fisher's exact test and logistic regression were used for analysis., Results: A total of 190 neonates were exposed to magnesium sulfate, while 211 neonates were not. The magnesium-exposed neonates were delivered at a significantly lower gestational age compared to the unexposed neonates (28.2 +/- 3.0 vs. 29.3 +/- 3.1 weeks, p = 0.001). Univariate analysis revealed no differences between groups with regard to rates of respiratory distress syndrome, intraventricular hemorrhage, periventricular leukomalacia, necrotizing enterocolitis, patent ductus arteriosus, histological and clinical chorioamnionitis, neonatal sepsis or neonatal death. However, magnesium-exposed neonates were more likely to have received antibiotics (71.6% vs. 45.0%, p = 0.0001) and antenatal steroids (95.8% vs. 61.6%, p = 0.0001), factors known to affect perinatal morbidity and mortality. Controlling for antenatal confounding factors, magnesium sulfate use was not independently associated with neonatal mortality (odds ratio (OR) = 0.66; 95% confidence interval (CI) = 0.28, 1.54; p = 0.34). Seventy-nine neonates were exposed to magnesium sulfate therapy for more than 24 h, while 111 neonates were exposed for 24 h or less. There were no significant differences between groups with respect to neonatal outcomes, with the exception of an increased rate of clinical chorioamnionitis in the group exposed to magnesium for more than 24 h (22% vs. 8.2%, p = 0.005). After adjusting for gestational age at delivery, magnesium sulfate exposure for over 24 h was independently associated with a 2.8-fold increased rate of clinical chorioamnionitis (OR = 2.8, 95% CI = 1.14, 6.90; p = 0.02)., Conclusion: Prenatal exposure to magnesium sulfate was not associated with increased neonatal morbidity or mortality. However, prolonged exposure to magnesium sulfate may be associated with an increased risk of clinical chorioamnionitis.

Background: Biotin deficiency is teratogenic in several mammalian species. Approximately 50% of pregnant women have an abnormally increased urinary excretion of 3-hydroxyisovaleric acid (3-HIA), which probably reflects decreased activity of the biotin-dependent enzyme methylcrotonyl-CoA carboxylase. However, increased 3-HIA excretion could result from pregnancy per se (eg, from an effect of pregnancy on renal handling of organic acids)., Objective: We tested the hypothesis that biotin supplementation significantly decreases 3-HIA excretion in pregnant women with abnormally increased 3-HIA excretion., Design: Twenty-six pregnant women with increased 3-HIA excretion were studied in a randomized, placebo-controlled trial; 10 women were studied during early pregnancy (6-17 wk gestation) and 16 women during late pregnancy (21-37 wk gestation). Urine samples were collected before and after 14 d of supplementation with 300 microg (1.2 micromol) biotin/d or placebo., Results: In the early-pregnancy group, 3-HIA excretion decreased (P < 0.006) by 11.7 +/- 3.6 mmol/mol creatinine (mean +/- SEM) in the 5 women who received biotin supplements, whereas 3-HIA excretion increased by 1.6 +/- 0.6 mmol/mol creatinine in the 5 women who received placebo. In the late-pregnancy group, 3-HIA excretion decreased (P < 0.002) by 7.1 +/- 1.2 mmol/mol creatinine in the 8 women who received biotin supplements, whereas 3-HIA excretion increased by 0.9 +/- 1.8 mmol/mol creatinine in the 8 women who received placebo., Conclusions: This study provides evidence that the increased excretion of 3-HIA seen frequently in normal pregnancy reflects reduced biotin status. The conclusion that marginal biotin deficiency occurs frequently in the first trimester further raises concern about potential human teratogenicity.

Adeno-associated virus (AAV) encoded Rep78 is a multi-functional protein which is required for AAV DNA replication, is able to regulate both AAV and heterologous gene expression at the transcriptional level, and appears necessary for site specific integration of AAV DNA into human chromosome 19. By comparison with the analogous replication protein of the polyomaviruses, large T antigen, it seemed likely that Rep78 would interact with cellular proteins to carry out at least some its functions. This study demonstrates that Rep78 is able to interact with multiple cellular proteins, from cellular extracts as measured by West(far)-western, coimmunoprecipitation, and Rep78-affinity chromatography analysis. Eight cellular proteins of approximately 180, 140, 120, 95, 75, 55, 45, and 35 kDa (+/- 10%), were observed to bind Rep78 in all three assay systems. Two others, of 30 and 24 kDa, were observed in two of three assay systems. Furthermore, using truncated Rep78 proteins, it is demonstrated that the amino-terminus is required for most Rep78-cellular protein interactions. However, the extreme carboxy-terminus of Rep78 was found to be all that is required for binding to the 55 kDa cellular protein.

Because of its ability to integrate chromosomally and its non-pathogenic nature, adeno-associated virus (AAV) has significant potential as a human gene therapy vector. Here we investigate the maximum amount of DNA which can be inserted into the AAV genome and still allow efficient packaging into an infectious virus particle. Altered wild-type AAV genomes were constructed with inserts, which increased in size by 100 bp, ligated at map unit 96. These large wild-type-plus genomes were able to replicate and produce infectious virus, at levels slightly reduced but comparable to normal sized wild type, until the insert size reached 1 kb. These data indicate that the maximum effective packaging capacity of AAV is approximately 900 bp larger than wild type, or 119%. Furthermore, it is demonstrated that these large AAV genomes are able to latently infect cells by chromosomal integration as does wild-type AAV. These data suggest that therapy vectors carrying a foreign gene of 900 bp or less can be generated from AAV, by ligation into non-essential locations, and result in a recombinant AAV virus with a fully wild-type phenotype. Such wild-type-plus AAV vectors will have both advantages and disadvantages over defective recombinant AAV virus - the most important advantages being the ease in which high titers of infectious virus can be generated and the ability to specifically integrate within chromosome 19. Once the concern subsides over the presence of wild-type AAV in clinical applications, wild-type AAV vectors may find specific application niches for use in human gene therapy.

In this study the possible role of human papillomaviruses (HPV) in spontaneous abortions is addressed by assaying for HPV DNA in first trimester spontaneous and electively aborted products of conception materials enriched for chorionic villi. The presence of HPVs was measured by polymerase chain reaction (PCR) amplification and DNA dot blot hybridization using an internal probe. The "broad spectrum" HPV primers were directed to amplify E6/E7 junction sequences, while the probe was of an HPV-16 sequence with significant homology to HPV-6/11. The quantity and quality of isolated DNA was also analyzed and compared by observing the PCR amplification of a cellular sequence from the human beta-globin gene. Fifteen of the 25 spontaneous samples (60%) were found to be positive for HPV E6/E7 sequences. In comparison, only 3 of the 15 elective samples (20%) were positive. This is the first study of HPV in fetal materials to incorporate material from elective abortions as a control group. Although confounding contamination from the cervix and vagina can't be ruled out, these data are significant and strongly suggest that HPVs are elevated in spontaneously aborted products of conception. Furthermore, these results suggest the possibility that HPVs may be etiologic agents of at least some spontaneous abortions.

Evidence is presented suggesting that CA125 is a serine and/or threonine phosphoprotein and that its secretion from the human amnion WISH cell line is closely linked to its phosphorylation. It is also indicated that regulation of CA125 secretion requires protein(s) tyrosine phosphorylation. WISH cells treated with a tyrosine phosphatase inhibitor, vanadate/ H2O2, resulted in increased levels of CA125 secretion. Exposure of vanadate-treated cells to epidermal growth factor further enhanced this secretory activity. Immunohistochemistry of vanadate-treated cells resulted in a substantial increase in not only cytoplasmic tyrosine phosphoproteins but also in membrane-associated CA125 when stained with the PY20 anti-phosphotyrosine and M11 anti-CA125 monoclonal antibodies, respectively. M11 immunoprecipitation of CA125 from cells labelled with [32P]-orthophosphate was analyzed by SDS-PAGE and autoradiography. Immunoprecipitates from cell lysates demonstrated that a phosphoprotein of > 200 kD was isolated and immunoreacted with both the OC125 and M11 anti-CA125 monoclonal antibodies by Western blotting. CA125 immunoprecipitated from vanadate-treated cells showed a marked increase in cell-associated CA125 phosphorylation. Although CA125 could be immunoprecipitated from WISH cell media incubated with [32P]-orthophosphate in the presence or absence of vanadate as detected by Western blotting, autoradiographic analysis of the Western blots revealed no [32P]-labelled CA125 co-migrating with the 200-kD plus molecule detected by M11. When the PY20 anti-phosphotyrosine monoclonal antibody was used as the probe, no tyrosine-phosphorylated CA125 was detected in cell lysates.

The adeno-associated virus (AAV) terminal repeats (TR) are cis required, and the AAV encoded Rep78 protein is trans required, for AAV DNA replication. The Rep78 protein recognizes and interacts with at least three regions within the TR DNA. The major binding site, with the highest affinity for Rep78 binding, is within the TR stem (nt 36-16) and includes the 'core' GAGC trimer (GAGC3, nt 33-22; Fig. 2) sequence. In this study mutations were made within the GAGC trimer and these mutants assayed for their ability to allow for AAV double stranded (ds DNA, prepackaging DNA replication), and single stranded DNA (ss DNA, due to virion packaging) replication. Here, it is shown that when the two inside GAGC motifs are mutated, with only motif no. 1 left intact (see Fig. 2), the resulting AAV (mutA) genome was significantly defective for both ds DNA (17% of wild type) and ss DNA (9%). If the TRs contained only the two outside motifs intact (mutB), motifs no. 1 and 2, the AAV genome had a significant but reduced level of both ds (50%) and ss (34%) DNA replication. Finally, if only the middle motif no. 2 was mutated, with motifs no. 1 and 3 left intact (mutC), the resulting DNA replication for both ds and ss forms was essentially wild type (80% that of wild type). These data suggest that the GAGC trimer plays a role in AAV DNA replication, and that GAGC motif no. 3 is the most important of the three motifs for both ds and ss DNA replication.

Objective: Our purpose was to determine the impact of delivery site, delivery mode, and delivery-to-surgery interval on outcomes for neonates diagnosed with gastroschisis., Study Design: Data were obtained retrospectively by chart review on 56 newborns diagnosed with gastroschisis. Outcome measures examined included primary closure, days to enteral feeding, days in intensive care, total length of stay, and hospital charges., Results: Inborn infants experienced fewer days to enteral feeding (p < 0.01)., shorter total lengths of hospital stay (p < 0.01), and lower hospital charges (p < 0.01). Newborns delivered by cesarean section tended to have longer lengths of stay (p = 0.07), greater hospital charges (p = 0.06), and significantly longer lengths of stay in intensive care (p = 0.05). Shorter intervals from delivery to surgery were observed for inborn neonates (p < 0.01) and for those delivered by cesarean section (p < 0.05). No relationships between hours from delivery to surgery and neonatal outcomes were observed., Conclusions: Delivery at a regional center is associated with improved outcomes, whereas cesarean deliveries were associated with worse outcomes. We observed no salutary effect related to the interval between delivery and initial surgical repair.

Routine amniocentesis for advanced maternal age led to the prenatal diagnosis of a fetus with a karyotype of a 46,XX,del(2)(p21p22). At delivery the baby had holoprosencephaly as the major clinical finding, which has been associated with a deletion of band 2p21 in several other case reports. Chromosome studies of the parents showed a normal 46,XY karyotype in the father, and a balanced interstitial insertion 46,XX dir ins (11;2)(p15.1;p21p22) in the mother. Subsequent chromosome studies of other relatives documented a 23-year-old half-brother of the proposita with a partial trisomy for the segment deleted in the proposita. The half-brother showed the derivative chromosome 11 from the mother, resulting in a 46,XY,der(11)dup(2)(p21p22) karyotype. Major clinical findings include short stature, mild developmental delay, and behavior abnormalities. A half-sister of the proposita is also a balanced carrier of the dir ins (11;2) (p15.1;p21p22.2). The association of the deletion chromosome band 2p21 and the clinical finding of holoprosencephaly is further supported by the findings in this family.

The ultrasound diagnosis of abdominal pregnancy continues to be difficult in spite of recent advances in ultrasound technology. The principal impediment is a low suspicion for the diagnosis because of its relatively asymptomatic nature and the lack of specificity of symptoms when present. In the early days of sonography when static B-mode scanning was used, a "gestalt" diagnosis was suggested, based on one's ability to have an overall perspective of the intrauterine contents. With conversion to exclusive real time imaging and the inherent limitation of the field of view, this "gestalt perception" is no longer possible. It is therefore necessary to reassess our criteria based on this change and determine those that remain reliable for diagnosis.

Objective: We studied the relation between epidermal growth factor (EGF)/epidermal growth factor receptor (EGFR) and CA125 production in WISH cells., Methods: We investigated quantitatively and immunohistochemically EGF-stimulated CA125 release from WISH cells and the effect of EGF on CA125 phosphorylation., Results: Immunohistochemical staining demonstrated that CA125 and EGFR expression on the plasma membrane of the WISH cells was closely correlated with cell density. The WISH cell monolayers (day 4) stained for CA125 in both the cytoplasm and plasma membrane. By day 8, cells began to form clumps in the surrounding monolayer that were positive for membrane-associated CA125 and EGFR, while the monolayer was almost negative for both molecules. Four-day and 8-day cells exposed to EGF demonstrated a loss of both CA125 and EGFR staining. Epidermal growth factor increased the secreted CA125 levels by 50% in day-4 cells but had no effect on day-8 cells. CA125 from WISH cells was phosphorylated, and EGF further enhanced this phosphorylation.

A 23-year-old female was referred to the University of Arkansas for Medical Sciences at 32 weeks' gestation with a history of aortic stenosis following aortic valve replacement. Evaluation by echocardiography showed an approximately 90 mmHg transvalvular pressure gradient. Pregnancy progressed to 36 weeks' gestation without problem, at which time the patient underwent cesarean section with lumbar epidural anesthesia. Invasive hemodynamic monitors were used to assess cardiac performance and as a guide for anesthetic management. The impact of aortic stenosis on pregnancy is discussed, as are management aspects of lumbar epidural anesthesia in such patients.