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Clinical/methodical Issue: Evaluation and confirmation of fetal pathologies previously suspected or diagnosed with ultrasound., Standard Radiological Methods: Ultrasound and magnetic resonance imaging (MRI)., Methodical Innovations: Technique for prenatal fetal examination., Performance: Fetal MRI is an established supplementary technique to prenatal ultrasound., Achievements: Fetal MRI should only be used as an additional method in prenatal diagnostics and not for routine screening., Practical Recommendations: Fetal MRI should only be performed in perinatal medicine centers after a previous level III ultrasound examination.

Cortical dysgenesia are a heterogenous group of genetic or acquired disturbances of cortical development which, due to the enormous progress in modern neuroimaging techniques, are increasingly recognized in association with a variety of clinical disorders. The spectrum of clinical manifestations, depending on type and extent of the alterations, includes severe mental retardation and epilepsy as well as neuropsychological deficits and some psychiatric disorders. Although pathogenesis and pathophysiology of cortical dysgenesis are still not fully understood, the recent discovery of responsible genes, growth factors, neurotransmitters, and exogenous factors sheds light on elementary mechanisms. The development of animal models mimicking different types of human cortical malformations helped to increase further the understanding of functional consequences of focal cortical dysgenesis. Several studies on these models reveal widespread alterations of cortical connectivity and excitability which are probably of crucial importance in different clinical disorders.

Aims/hypothesis: To assess the relation between glycaemic control in early pregnancy and the risk of congenital malformations in offspring of mothers with Type I (insulin-dependent) diabetes mellitus., Methods: From 1988-1997, we prospectively collected data from 691 pregnancies and 709 offspring of 488 women with Type I diabetes in a specific geographic area in Southern Finland. Glycated haemoglobin A1c at less than 14 weeks of gestation was used as the indicator of glycaemic control. The malformations were diagnosed either by ultrasonography in pregnancy or during the neonatal period. We also studied 729 non-selected control pregnancies in women without diabetes., Results: The numbers of major fetal malformations were 30 (4.2%) in patients with Type I diabetes and 10 (1.2%) in the control subjects (relative risk 3.1; 95% confidence interval: 1.6 to 6.2). Even women whose HbA1c was only slightly raised (5.6 to 6.8%, i.e. 2.0 to 5.9 standard deviation units) showed a relative risk of 3.0 (95% confidence interval: 1.2 to 7.5). Haemoglobin A1c retained its statistically significant association with the occurrence of malformations after adjusting for White's class, age at onset of diabetes, duration of diabetes, parity, smoking and participation in pre-pregnancy counselling., Conclusions/interpretation: Even a slightly raised HbA1c during early pregnancy in women with Type I diabetes carries an increased risk for fetal malformations. Therefore normoglycaemia should be strived for during early pregnancy.

In PCR-supported amplification of ancient, degraded DNA, contamination with contemporary DNA can lead to false-positive results, which frequently give rise to discussions in which the mere existence of ancient DNA is doubted. Our confirmation of ancient DNA using comparative genome hybridization (CGH) eliminates these doubts. Unlike PCR methods, CGH requires no amplification of the DNA to be analyzed if adequate amounts of specimen DNA is used. Thus, false results traceable to contaminations are practically ruled out. The examples provided here prove the authenticity of ancient DNA for a 250-year-old and a 3,000-year-old sample. At the same time, the CGH of ancient DNA offers the chance to gain insight into the pattern of DNA degradation and to monitor the preservation of certain chromosomal segments.

We wanted to determine whether administration of vitamin E could reduce the production of free radicals which could play a role in the teratogenic effects of diabetes mellitus. Diabetes was induced in Wistar rats by the intravenous administration of streptozotocin. The animals were divided into six groups: one with no supplement (D) and two, supplemented during pregnancy either with oral vitamin E (150 mg/day) (D + E) or with a placebo (safflower oil) (D + O). Three other groups were kept under the same conditions, but were treated with insulin: D + I, D + I + E and D + I + O. There were three groups of matched controls: C, C + E and C + O. All animals were killed on day 11.5 of pregnancy. In C animals the percentages of reabsorptions and malformations were 1.3 and 2%, respectively, compared with 23.6, 24.3, 6.2 and 13.2%, respectively in D and D + I groups. The crown-rump length, number of somites, and protein and DNA content were higher in C animals than in the diabetic rats, independent of insulin treatment. When vitamin E was administered no changes in these parameters were observed in C and D + I animals; however, in the D mothers it reduced the rate of embryo malformations to 4.6% and increased the crown-rump length and the number of somites. However, vitamin E did not modify the protein and DNA content and the percentage of reabsorptions. In conclusion, administration of vitamin E to diabetic animals decreases the rate of embryo malformations and increases their size and maturation, supporting a role for free radicals in the teratogenic effects of diabetes.

Fetuses from normal and manifestly diabetic rats were obtained on pregnancy day 20. The fetuses from the diabetic rats were of normal or malformed morphology. Three tissue groups were dissected free; costal cartilage, the hard tissue of the rear, and of the frontal portion of the mandible. These tissues were maintained in vitro for 24 h during which time they were labelled with [35S]sulphate. After the culture period the tissues were extracted with guanidine HCl and the resulting residues were further extracted with alkali. The culture medium was saved and its macromolecular content was compared to that of the extracts. The proteoglycans recovered in all extracts eluted at two distinct positions after chromatography on a Sepharose CL-2B column (peak I: Kav approximately 0.4, and peak II: Kav approximately 0.8), but the elution patterns were markedly different in extracts from various tissues. Thus, in rib cartilage, the majority of the labelled proteoglycans were located in peak I (approximately 90%) with no difference between extracts of fetuses from normal and diabetic pregnancies. In extracts of mandibular cartilaginous tissue from normal rat offspring the peak I percentage (60-80%) was lower than in the rib cartilage extracts. In the extracts from the frontal portion of malformed mandibles of fetuses of diabetic rats, the peak I percentage (35 +/- 21%) was the lowest of all recorded and the only one to significantly differ from the other percentages in its (the frontal mandible) group. The results show an association between a congenital malformation, micrognathia, and a disturbance in the production of chondroitin sulphate proteoglycans in the malformed region.

Recently, tremendous advances have been made in our understanding of pre- and perinatal death and congenital anomaly, but many aspects of the field remain unknown and require the continued collaboration of workers in many clinical and basic science disciplines. Most of mankind dies before, not after birth, mostly due to chromosome abnormalities arising during pregenesis. A few trisomy 13 and 18 cases survive till birth by virtue of placental mosaicism; even trisomy 21 is an 80% prenatally lethal and a postnatally sublethal syndrome. Most aneuploid individuals surviving postnatally have sex chromosomes abnormalities (47,XXY, 47,XYY, 47,XXX). Until recently the term "monsters" was applied to many abnormalities of blastogenesis--i.e. the disruptions and malformations arising during the first 4 weeks of embyronic development (till the end of mesoderm formation). This includes not only acardia/acephaly, but also holoprosencephaly, sirenomelia, gross defects of cord, body wall and -stalk formation and conjoined twins, but also non-conjoined monozygotic twins with apparent high prenatal mortality and a high incidence of midline anomalies. One of the most important recent insights has been that associations, e.g. the VACTERAL association, and the relatively characteristic combination of anomalies seen in infants of diabetic mothers, represent disruptions of blastogenesis. The latter represent a particularly satisfying development in the field since it has been shown that control of the woman's blood sugar levels before, during and after conception helps to reduce the high incidence of defects of blastogenesis in infants of diabetic mothers. Most malformations arise during organogenesis in secondary or epimorphic fields and mostly represent anomalies of incomplete, less commonly of abnormal differentiation. An important distinction must be made between mild malformations (all-or-none defects of organogenesis) which are relatively innocuous and common in the population but never normal, and minor anomalies which are graded defects of phenogenogenesis (i.e. of the developmental processes during the fetal period (weeks 8-10 p.c.), and the most frequent anomalies in aneuploidy syndromes with resulting loss of family resemblance.(ABSTRACT TRUNCATED AT 400 WORDS)

In the study of 273 aortic arch angiograms, one case of right vertebral artery arising from the right common carotid artery was encountered. The embryology of this anomaly and its clinical significance are discussed.

Our case of azygos continuation of the inferior vena cava is very rare because there was no associated heart disease or abdominal situs inversus. The diagnosis of this anomaly of the inferior vena cava should be suspected by observation of a dilated azygos vein on the chest roentgenogram and confirmed by venography.