bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sonography of pregnancies with first‐trimester bleeding and a small intrauterine gestational sac without a demonstrable embryo
Authors: Falco P. , Zagonari S. , Gabrielli S. , Bevini M. , Pilu G. , Bovicelli L. 
Published: January 2003

AbstractObjectiveThis was a prospective observational cohort study to evaluate the outcome and prognostic criteria of pregnancies with first‐trimester bleeding and a gestational sac ≤16 mm without a demonstrable embryo.MethodsCriteria for admission into the study included: (1) first‐trimester bleeding; (2) a transvaginal scan performed upon admission demonstrating a single intrauterine gestational sac with a mean diameter ≤16 mm and without a demonstrable embryo. The outcome variable was miscarriage, defined as pregnancy loss prior to 22 weeks. The following explanatory variables were considered: maternal age, menstrual age, size of the gestational sac, presence or absence of the yolk sac and subchorionic hematoma, and β‐human chorionic gonadotropin levels. The relationship of these variables with pregnancy failure was analyzed by stepwise logistic regression.ResultsOf 50 patients, 32 (64%) underwent miscarriage. The receiver–operating characteristics (ROC) curve of the size of the gestational sac demonstrated a high level of statistical significance (area under the ROC curve 0.9080, P < 0.000001) and stepwise logistic regression revealed that this was the only variable independently correlated with the subsequent occurrence of miscarriage.DiscussionIt is commonly accepted that in pregnant patients with first‐trimester bleeding, demonstration by transvaginal ultrasound of an intrauterine gestational sac ≤16 mm without an embryo may be compatible with a viable pregnancy. Our results suggest that in general this finding is associated with a poor outcome, with miscarriage occurring in two‐thirds of patients. When the sac is small for gestational age, the risk of miscarriage is greatly increased. In the present series, a gestational sac diameter less than −1.34 standard deviations of the mean was associated with pregnancy failure in over 90% of cases. Copyright © 2002 ISUOG. Published by John Wiley & Sons, Ltd.
Treatment of severe fetal chylothorax associated with pronounced hydrops with intrapleural injection of OK‐432
Authors: Jorgensen C. , Brocks V. , Bang J. , Jorgensen F. S. , Rønsbro L. 
Published: January 2003

AbstractWe describe a case of a 25‐week fetus with severe bilateral pleural effusion, marked ascites, skin edema, an anterior thick (hydropic) placenta and polyhydramnios in which the most probable diagnosis was congenital chylothorax. Treatment with a pleuroamniotic shunt was planned, however the location of the fetus just below the anterior placenta made the placement of the shunt too dangerous. We therefore decided to use intrapleural injection of OK‐432. From week 29, the lungs looked normal, the pleural effusion had resolved and the thoracic circumference was within normal limits. The severe ascites persisted throughout the pregnancy and a total volume of 3680 mL was removed on several occasions. A Cesarean section was performed at 38 weeks and a normal male was delivered. Continuous positive airway pressure was needed on the first 4 days but after a week the situation was stable. On day 8, an X‐ray showed normally developed lungs. OK‐432 appears to have prevented pulmonary hypoplasia in our patient. Copyright © 2003 ISUOG. Published by John Wiley & Sons, Ltd.
Audit of prenatal and postnatal diagnosis of isolated open spina bifida in three university hospitals in The Netherlands
Authors: Olde Scholtenhuis M. A. G. , Cohen‐Overbeek T. E. , Offringa M. , Barth P. G. , Stoutenbeek Ph. , Gooskens R. H. , Wladimiroff J. W. , Bilardo C. M. 
Published: January 2003

AbstractObjectiveTo audit the current Dutch policy of prenatal detection of isolated open spina bifida based on offering detailed ultrasound examination only on indication.MethodsA retrospective analysis of prenatally diagnosed isolated spina bifida cases and of newborns diagnosed with this condition was carried out in three university hospitals. The data were collected from databases and clinical records of the departments of prenatal diagnosis, obstetrics, neonatology, child neurology and neurosurgery of the three centers.ResultsBetween January 1996 and December 1999, 88 cases of isolated open spina bifida were diagnosed prenatally by ultrasound investigation. Thirty‐eight cases (43%) were diagnosed before the 24th week of gestation. Of these, 35 (92%) ended in termination of the pregnancy at the parents' request. Of the remaining 50 cases (57%) diagnosed after the 24th week of gestation, eight (16%) pregnancies were terminated beyond the legal limit for termination due to the severity of the condition. Of the 88 cases of isolated spina bifida, 25 infants (28%) were still alive at the age of 4 years. In the same audit period 112 newborn infants with isolated open spina bifida were admitted to the neonatology, child neurology, or neurosurgery ward of the three centers. Of these cases, 47 (42%) had been diagnosed prenatally and 65 (58%) were an unexpected finding at birth. In 24 infants (21%) surgical treatment was withheld because of the severity of the condition and predicted poor outcome, whereas the remaining 88 infants (79%) underwent surgical repair.ConclusionThe current practice in The Netherlands of offering ultrasound screening to high‐risk patients only leads to the early detection of a minority of cases of spina bifida. Most cases are diagnosed either after the 24th week of gestation or they remain undiagnosed until after birth. When spina bifida is diagnosed before the 24th week of gestation the vast majority of parents opt for termination. In order to reduce the birth prevalence of spina bifida in The Netherlands the introduction of a policy of routine ultrasound screening should be considered. Copyright © 2003 ISUOG. Published by John Wiley & Sons, Ltd.
Echocardiographic evaluation of fetal hydrothorax: the effusion ratio as a diagnostic tool
Authors: Bigras J.‐L. , Ryan G. , Suda K. , Silva A. E. , Seaward P. G. R. , Windrim R. , McCrindle B. W. 
Published: January 2003

AbstractObjectiveFetal hydrothorax may lead to hydrops and is associated with mortality as high as 50%. The objective of this study was to define the pathophysiology of fetal hydrothorax and its relation to hydrops.MethodsMeasurements from echocardiograms of 33 fetuses diagnosed with hydrothorax were made, and included diameters of the thorax, heart, inferior vena cava, right ventricle (RV), left ventricle (LV) and aortic and pulmonary valves. Doppler‐derived velocities were measured in the aorta and pulmonary artery just above the aortic and pulmonary valves. The ratio of the area of the effusion to the area of the thorax (effusion ratio) was calculated. Variables were converted into Z‐scores from regression equations based on normal data. Features of fetuses with and without hydrops were compared.ResultsHigher effusion ratios were noted in hydropic versus non‐hydropic fetuses. Compared to a normal population, study subjects had smaller dimensions of LV, RV and aortic and pulmonary valves. They also had higher pulmonary artery peak velocities. The comparison between non‐hydropic and hydropic fetuses revealed lower values for LV and pulmonary valve dimensions, and peak aortic velocity in hydropic fetuses. The severity of LV compression correlated significantly with effusion ratio.ConclusionFetal hydrothorax is accompanied by compression of the cardiac structures, resulting in altered cardiac hemodynamics. Echocardiographic assessment, including the measurement of effusion ratio, may be a useful tool in guiding fetal therapy. Copyright © 2003 ISUOG. Published by John Wiley & Sons, Ltd.
Three cross‐sectional planes for fetal color Doppler echocardiography
Authors: Chaoui R. , McEwing R. 
Published: January 2003

AbstractRoutine use of color Doppler during every fetal cardiac examination remains controversial. Many examiners still believe that color should be reserved for cases of suspected congenital heart defect (CHD). In our opinion, color Doppler should be applied in every cardiac scan due to the increase in speed and accuracy that it allows. The purpose of this review is to first explain how color Doppler presets can be optimized and, second, to propose the use of three cross‐sectional planes to simplify color Doppler fetal echocardiography: the four‐chamber (4CV), five‐chamber (5CV) and three‐vessel (3VV) views. A practical approach to the detection of CHD with these planes is presented, with typical findings and possible abnormalities evident during systole and diastole. The diastolic pattern on the 4CV is characterized by two equal color stripes. Connection (‘H’‐sign) or size inequality of the two stripes, or a unilateral color stripe, are important abnormal findings. In systole valve regurgitation should be excluded. In the 5CV, turbulent flow, ventricular septal defect or an overriding aorta (‘Y’‐sign) can be detected. In the 3VV the aorta and pulmonary trunk should be of nearly equal size and demonstrate antegrade flow. Abnormal findings encountered include absence of one vessel, discrepant size of the vessels, retrograde flow in one of the vessels, or the ‘U’‐sign, where the trachea is enclosed between both vessels, suggesting right‐sided aortic arch. In summary, we propose that color Doppler examination utilizing these three planes alone is sufficient to obtain adequate information for the detection of most common CHD. Copyright © 2002 ISUOG. Published by John Wiley & Sons, Ltd.
Outcome of children with prenatally diagnosed central nervous system malformations
Authors: Adama Van Scheltema P. N. , Nagel H. T. C. , Brouwer O. F. , Vandenbussche F. P. H. A. 
Published: January 2003

AbstractObjectiveTo study the outcome of pregnancies with a prenatally diagnosed central nervous system (CNS) malformation.MethodsLeiden University Medical Centre is a tertiary referral center for fetal ultrasound and invasive prenatal diagnosis. Maternal and neonatal records of prenatally diagnosed CNS malformations were retrospectively reviewed over a 6‐year period (1993–1998). Information on current development of surviving children was obtained by contacting the care‐giving pediatric neurologist.ResultsDuring the study period 124 fetuses were diagnosed with a CNS malformation. Data on pregnancy and delivery were available for 118 pregnancies. Additional malformations were present in 47% of fetuses (55/118). A total of 46% of pregnancies (54/118) were terminated, and 15% (18/118) ended in spontaneous intrauterine death. A total of 39% of pregnancies (46/118) resulted in live birth, and 29 of the infants were still alive at the age of 3 months. One child was lost to follow‐up, one infant died at the age of 4 months, and two children died at the age of 3 years. Psychomotor development of the remaining 25 children was normal for five, slightly disabled for seven, moderately disabled for five and severely disabled for eight.ConclusionDue to the high rate of termination of pregnancy and to the frequent association with other anomalies, the survival rate of pregnancies in which a CNS defect had been diagnosed prenatally was only 25%. More than 50% of surviving children were moderately or severely disabled. Copyright © 2002 ISUOG. Published by John Wiley & Sons, Ltd.
Factors influencing the prenatal detection of structural congenital heart diseases
Authors: Wong S. F. , Chan F. Y. , Cincotta R. B. , Lee‐Tannock A. , Ward C. 
Published: January 2003

AbstractObjectiveTo assess the factors influencing the prenatal detection rate of structural congenital heart diseases (CHDs).MethodsA retrospective study was conducted at a major obstetric hospital in Australia between 1 January 1996 and 30 June 1999. The medical records of all fetuses and infants born with CHD, except those with isolated patent ductus arteriosus or secundum atrial septal defect, were reviewed. Only pregnancies that had prenatal ultrasound scan assessments for morphological surveys were included. The following factors that may influence the detection rate were assessed: complexity of the lesions; experience of the sonographers (performance in tertiary versus non‐tertiary institutions); presence of other structural or chromosomal anomalies; and maternal body mass index (BMI).ResultsThe incidence of structural CHD in this series, excluding cases referred from other hospitals, was 7.0 per 1000 (179/25 529). Of the 179 pregnancies with CHD, 151 had prenatal ultrasound scans and were included in the study. The overall detection rate for CHDs in this series was 40.4%. The detection rate for isolated septal defects was poor (13.7%). The detection rates were significantly higher for complex lesions (54%), for lesions with concomitant septal defects (66.7%), and for lesions with abnormal four‐chamber views (62.9%). The detection rate was also higher if the scan was performed in the tertiary institution, and if there were other chromosomal or structural anomalies. Maternal BMI did not affect the detection rate in the current series. Stepwise logistic regression analysis showed that three independent variables affecting the detection rate were complexity of the cardiac lesion, experience of the operator, and the detection of chromosomal anomalies.ConclusionA high detection rate for major CHDs can be achieved in a screening setting but there is still room for improvement in scanning skills in the four‐chamber view and great‐artery analysis in both tertiary and local centers. Copyright © 2002 ISUOG. Published by John Wiley & Sons, Ltd.
Fetal tissue Doppler echocardiography: detection rates of cardiac structures and quantitative assessment of the fetal heart
Authors: Tutschek B. , Zimmermann T. , Buck T. , Bender H. G. 
Published: January 2003

AbstractObjectivesTissue Doppler echocardiography (TDE) has been developed in adult cardiology, but only recently has it been applied to fetal heart studies. We implemented TDE on a high‐resolution ultrasound system used for prenatal scanning by changing the Doppler settings, but without specific TDE equipment, to study cardiac tissue motion of normal fetuses in the second and third trimesters.MethodsUsing color Doppler settings optimized for low velocity motion assessment, detection rates of cardiac structures were measured in 47 fetuses. With pulsed Doppler, axial diastolic and systolic cardiac wall velocities were recorded in another 30 fetuses.ResultsIn all fetuses TDE could detect cardiac wall motion. The right ventricular wall and the level of the atrioventricular valves were most easily seen. Axial contraction velocities of the fetal heart increased with gestational age.ConclusionsTDE can be used to study normal fetal cardiac function throughout gestation. A regular ultrasound system without additional hardware or software is suitable for screening studies using TDE. Copyright © 2002 ISUOG. Published by John Wiley & Sons, Ltd.
Reevaluating Human Gene Annotation: A Second-Generation Analysis of Chromosome 22
Authors: Collins John E. , Goward Melanie E. , Cole Charlotte G. , Smink Luc J. , Huckle Elizabeth J. , Knowles Sarah , Bye Jacqueline M. , Beare David M. , Dunham Ian 
Published: January 2003

We report a second-generation gene annotation of human chromosome 22. Using expressed sequence databases, comparative sequence analysis, and experimental verification, we have extended genes, fused previously fragmented structures, and identified new genes. The total length in exons of annotation was increased by 74% over our previously published annotation and includes 546 protein-coding genes and 234 pseudogenes. Thirty-two potential protein-coding annotations are partial copies of other genes, and may represent duplications on an evolutionary path to change or loss of function. We also identified 31 non-protein-coding transcripts, including 16 possible antisense RNAs. By extrapolation, we estimate the human genome contains 29,000–36,000 protein-coding genes, 21,300 pseudogenes, and 1500 antisense RNAs. We suggest that our revised annotation criteria provide a paradigm for future annotation of the human genome.[Supplemental material is available online at www.genome.org. The sequence data from this study have been submitted to GenBank under accession nos. AL009266, AL021682-3,AL021708, AL022729, AL035081-2, AL035364, AL035366, AL035545, AL049654,AL050253-8, AL050345-6, AL079310, AL096779-81, AL096879-81, AL096883,AL096886, AL138578, AL157851, AL159142-3, AL160111-2, AL160131-2,AL160311, AL355092, AL355192, AL355841, AL359401, AL359403, AL365511-5,AL442116, AL449243, AL449244, AL450314, AL589866-7, AL590120,AL590887-8, BU583989–BU585359. The following individuals kindly provided reagents, samples, or unpublished information as indicated in the paper: J. Seilhamer, L. Stuve, H. Roest-Crollius, A. Levine, G. Slater, and J. Kent.]
Genome Rearrangements in Mammalian Evolution: Lessons From Human and Mouse Genomes
Authors: Pevzner Pavel , Tesler Glenn 
Published: January 2003

Although analysis of genome rearrangements was pioneered by Dobzhansky and Sturtevant 65 years ago, we still know very little about the rearrangement events that produced the existing varieties of genomic architectures. The genomic sequences of human and mouse provide evidence for a larger number of rearrangements than previously thought and shed some light on previously unknown features of mammalian evolution. In particular, they reveal that a large number of microrearrangements is required to explain the differences in draft human and mouse sequences. Here we describe a new algorithm for constructing synteny blocks, study arrangements of synteny blocks in human and mouse, derive a most parsimonious human–mouse rearrangement scenario, and provide evidence that intrachromosomal rearrangements are more frequent than interchromosomal rearrangements. Our analysis is based on the human–mouse breakpoint graph, which reveals related breakpoints and allows one to find a most parsimonious scenario. Because these graphs provide important insights into rearrangement scenarios, we introduce a new visualization tool that allows one to view breakpoint graphs superimposed with genomic dot-plots.[Supplemental material is available online atwww.genome.org.]
Pericentromeric Duplications in the Laboratory Mouse
Authors: Thomas James W. , Schueler Mary G. , Summers Tyrone J. , Blakesley Robert W. , McDowell Jennifer C. , Thomas Pamela J. , Idol Jacquelyn R. , Maduro Valerie V.B. , Lee-Lin Shih-Queen , Touchman Jeffrey W. , Bouffard Gerard G. , Beckstrom-Sternberg Stephen M. , Program NISC Comparative Sequencing , Green Eric D. 
Published: January 2003

Duplications have long been postulated to be an important mechanism by which genomes evolve. Interspecies genomic comparisons are one method by which the origin and molecular mechanism of duplications can be inferred. By comparative mapping in human, mouse, and rat, we previously found evidence for a recent chromosome-fission event that occurred in the mouse lineage. Cytogenetic mapping revealed that the genomic segments flanking the fission site appeared to be duplicated, with copies residing near the centromere of multiple mouse chromosomes. Here we report the mapping and sequencing of the regions of mouse chromosomes 5 and 6 involved in this chromosome-fission event as well as the results of comparative sequence analysis with the orthologous human and rat genomic regions. Our data indicate that the duplications associated with mouse chromosomes 5 and 6 are recent and that the resulting duplicated segments share significant sequence similarity with a series of regions near the centromeres of the mouse chromosomes previously identified by cytogenetic mapping. We also identified pericentromeric duplicated segments shared between mouse chromosomes 5 and 1. Finally, novel mouse satellite sequences as well as putative chimeric transcripts were found to be associated with the duplicated segments. Together, these findings demonstrate that pericentromeric duplications are not restricted to primates and may be a common mechanism for genome evolution in mammals.[Supplemental material is available online at www.genome.org.]
The Comprehensive Mouse Radiation Hybrid Map Densely Cross-Referenced to the Recombination Map: A Tool to Support the Sequence Assemblies
Authors: Rowe Lucy B. , Barter Mary E. , Kelmenson Jennifer A. , Eppig Janan T. 
Published: January 2003

We have developed a unique comprehensive mouse radiation hybrid (RH) map of nearly 23,000 markers integrating data from three international genome centers and over 400 independent laboratories. We have cross-referenced this map to the 0.5-cM resolution recombination-based Jackson Laboratory (TJL) backcross panel map, building a complete set of RH framework chromosome maps based on a high density of known-ordered anchor markers. We have systematically typed markers to improve coverage and resolve discrepancies, and have reanalyzed data sets as needed. The cross-linking of the RH and recombination maps has resulted in a highly accurate genome-wide map with consistent marker order. We have compared these linked framework maps to the Ensembl mouse genome sequence assembly, and show that they are a useful medium resolution tool for both validating sequence assembly and elucidating chromosome biology.[Supplemental material is available online at www.genome.org.]
The Companion Cell-Specific Arabidopsis Disaccharide Carrier AtSUC2 Is Expressed in Nematode-Induced Syncytia
Authors: Juergensen Katja , Scholz-Starke Joachim , Sauer Norbert , Hess Paul , van Bel Aart J.E. , Grundler Florian M.W. 
Published: January 2003

Abstract
Cyst nematodes induce a metabolically highly active syncytial cell complex in host roots. The syncytia are symplastically isolated. Because they form a strong sink, assimilates must be imported via the apoplast, thus suggesting that specific membrane-bound sugar transport proteins are expressed and activated. To identify possible candidate genes, transgenic Arabidopsis plants expressing different reporter genes under the control of different promoters from Arabidopsis sugar transporter genes were infected with the beet cyst nematode (Heterodera schachtii). With polymerase chain reaction, 13 additional sugar transporters were tested for their presence in the syncytia through the use of a syncytium-specific cDNA library. Analysis of the infected roots showed that the promoter of the sucrose (Suc) transporter AtSUC2 gene that codes for a companion cell-specific Suc transporter in noninfected plants was found to be expressed in syncytia. Its expression patterns in β-glucuronidase and green fluorescent protein plants were monitored. Syncytium-specific gene expression was confirmed by reverse transcriptase-polymerase chain reaction. Results support the idea that AtSUC2 mediates the transmembrane transfer of Suc. AtSUC2 is the first disaccharide carrier described to be activated by pathogens.