Fetal Cardiac Effects of Maternal Hyperglycemia During Pregnancy

Maternal diabetes mellitus is associated with increased teratogenesis, which can occur in pregestational type 1 and type 2 diabetes. Cardiac defects and with neural tube defects are the most common malformations observed in fetuses of pregestational diabetic mothers. The exact mechanism by which diabetes exerts its teratogenic effects and induces embryonic malformations is unclear. Whereas the sequelae of maternal pregestational diabetes, such as modulating insulin levels, altered fat levels, and increased reactive oxygen species, may play a role in fetal damage during diabetic pregnancy, hyperglycemia is thought to be the primary teratogen, causing particularly adverse effects on cardiovascular development. Fetal cardiac defects are associated with raised maternal glycosylated hemoglobin levels and are up to five times more likely in infants of mothers with pregestational diabetes compared with those without diabetes. The resulting anomalies are varied and include transposition of the great arteries, mitral and pulmonary atresia, double outlet of the right ventricle, tetralogy of Fallot, and fetal cardiomyopathy.

Hirschsprung's disease prevalence in Europe: A register based study

Background: Hirschsprung's disease is a congenital gut motility disorder, characterised by the absence of the enteric ganglion cells along the distal gut. The aim of this study was to describe the epidemiology of Hirschsprung's disease, including additional congenital anomalies, total prevalence, trends, and association with maternal age. Methods: Cases of Hirschsprung's disease delivered during 1980 to 2009 notified to 31 European Surveillance of Congenital Anomaly registers formed the population-based case-series. Prevalence rates and 95% confidence intervals were calculated as the number of cases per 10,000 births. Multilevel Poisson regression was performed to investigate trends in prevalence, geographical variation and the association with maternal age. Results: There were 1,322 cases of Hirschsprung's disease among 12,146,210 births. The total prevalence was 1.09 (95% confidence interval, 1.03–1.15) per 10,000 births and there was a small but significant increase in prevalence over time (relative risk = 1.01; 95% credible interval, 1.00–1.02; p = 0.004). There was evidence of geographical heterogeneity in prevalence (p < 0.001). Excluding 146 (11.0%) cases with chromosomal anomalies or genetic syndromes, there were 1,176 cases (prevalence = 0.97; 95% confidence interval, 0.91–1.03 per 10,000 births), of which 137 (11.6%) had major structural anomalies. There was no evidence of a significant increased risk of Hirschsprung's disease in cases born to women aged ≥35 years compared with those aged 25 to 29 (relative risk = 1.09; 95% credible interval, 0.91–1.31; p = 0.355). Conclusion: This large population-based study found evidence of a small increasing trend in Hirschsprung's disease and differences in prevalence by geographic location. There was also no evidence of an association with maternal age.

Neurological, psychological and educational sequelae of low birth weight

In a prospective study of 501 infants of low birth weight (LBW) who mostly weighed 2,041 g (4 1/2 lb) or less, and of 203 control infants of full birth weight (FBW > 2,500 g), 335 LBW and 139 FBW children were followed beyond the age of 6 years and 6 months. The incidence of neurological defects was negatively correlated with birth weight, and the mean "global" IQ of different birth weight groups retained a direct relationship. While the relationship of birth weight to IQ gradually became less marked, the effect of social class was increasingly evident from the age of 2 years and 6 months. The preterm children whose birth weight was appropriate for gestational age (AGA) attained a slightly higher mean IQ and significantly better grade placement in the third school year than the children who were unduly light for their gestational age. Details of the neurological and ophthalmological defects are given, and the predictive significance of neonatal variables is analyzed.

Birth technology competence: a concept analysis

Aim. To identify birth technology competencies used by midwives to support women during the birthing process and to explore the concept of birth technology competence in midwifery practice in order to inform both education and practice. Objective. To define attributes of birth technology competence. Method. The Chinn and Kramer framework for concept analysis was used to examine sources including popular and professional literature, government reports and statutory regulation. The model allows for the exploration of three areas of experience, which interact to form the meaning of an idea or concept – feelings, values and attitudes associated with the concept, the symbolic label for the concept and the concept itself. Results. Exploration of the literature led to the development of exemplar cases that illuminate tentative attributes of the concept, contained within three domains – interpersonal skills, professional knowledge and clinical proficiency. Implications. Following testing in midwifery practice to ensure its transferability into the clinical context, the theoretical perspective developed here will provide a basis to inform education and practice in relation to the use of technology.

Monte Carlo simulation of cluster growth in surface defects induced by the tip of a scanning tunnelling microscope

First steps are taken to model the electrochemical deposition of metals in nanometer-sized cavities. In the present work, the electrochemical deposition of Cu atoms in nanometer-sized holes dug on Au(111) is investigated through Monte Carlo simulations using the embedded atom method to represent particle interactions. By sweeping the chemical potential of Cu, a cluster is allowed to grow within the hole rising four atomic layers above the surface. Its lateral extension remains confined to the area defined by the borders of the original defect. (C) 2004 Elsevier B.V. All rights reserved.

Virgin birth in a hammerhead shark.

Parthenogenesis has been documented in all major jawed vertebrate lineages except mammals and cartilaginous fishes (Class Chondrichthyes: sharks, batoids, chimeras). Reports of captive female sharks giving birth despite being held in the extended absence of males have generally been ascribed to prior matings coupled with long-term sperm storage by the females. Here we provide the first genetic evidence for chondrichthyan parthenogenesis, involving a hammerhead shark. This finding also broadens the known occurrence of a specific type of asexual development (automictic parthenogenesis) among vertebrates, extending recently raised concerns about the potential negative effect of this type of facultative parthenogenesis on the genetic diversity of threatened vertebrate species.

The Influence of Point Defects and Inhomogeneous Strain on the Functional Behaviour of Thin film Ferroelectrics

An attempt has been made to unequivocally identify the influence that inhomogeneous strain fields, surrounding point defects, have on the functional properties of thin film ferroelectrics. Single crystal thin film lamellae of BaTiO3 have been integrated into capacitor structures, and the functional differences between those annealed in oxygen and those annealed in nitrogen have been mapped. Key features, such as the change in the paraelectric-ferroelectric phase transition from first to second order were noted and found to be consistent with mean field modeling predictions for the effects of inhomogeneous strain. Switching characteristics appeared to be unaffected, suggesting that point defects have a low efficacy in domain wall pinning.