3D ultrasound in fetal spina bifida

3D ultrasound can be used to study the fetal spine, but skeletal mode can be inconclusive for the diagnosis of fetal spina bifida. We illustrate a diagnostic approach using 2D and 3D ultrasound and indicate possible pitfalls

Approximately half of the erythroblasts in maternal blood are of fetal origin

The enrichment of fetal erythroblasts from the peripheral blood of pregnant women is currently actively pursued for the development of a non-invasive means of prenatal diagnosis. Since erythroblasts in maternal blood are not all of fetal origin, and currently no reliable method exists to distinguish between the maternal and fetal erythroblasts, their use for prenatal diagnosis is not without uncertainty. The purpose of this study was to determine the percentage of fetal erythroblasts in maternal blood at the single cell level and to what extent such cells can reproducibly be used for polymerase chain reaction (PCR)-based prenatal diagnostic analyses. Erythroblasts were enriched from the peripheral blood of rhesus negative pregnant women using magnetic cell sorting (MACS). Single erythroblasts identified morphologically were individually micromanipulated and analysed by a multiplex PCR reaction for the fetal SRY and rhesus D genes. As a control for the PCR reaction the β-globin gene was used. The PCR results were validated by the results obtained by invasive procedures. In all instances where single erythroblasts were examined, the correct fetal genotype for the two fetal specific loci was detected. Furthermore, our results indicate that ~50% of the enriched erythroblasts are of fetal origi

Choice of anticoagulant can influence the analysis using fluorescence in situ hybridization of fetal cells enriched from maternal blood

A notable degree of research attention is being focused on the use of fetal cells enriched from the blood of pregnant women as a non-invasive means of prenatal diagnosis. By using magnetic activated cells sorting (MACS) and fluorescence in situ hybridization (FISH), we have examined the efficacy of enriched fetal cells in determining fetal sex. An unexpected finding of this investigation was that the sensitivity of this analysis was influenced by the anticoagulant used to treat the maternal blood samples. As such, samples treated with heparin showed significantly lower detection rates than samples chelated with EDTA

HNCcorr: A Novel Combinatorial Approach for Cell Identification in Calcium-Imaging Movies

AbstractCalcium imaging is a key method in neuroscience for investigating patterns of neuronal activityin vivo. Still, existing algorithms to detect and extract activity signals from calcium-imaging movies have major shortcomings. We introduce the HNCcorr algorithm for cell identification in calcium-imaging datasets that addresses these shortcomings. HNCcorr relies on the combinatorial clustering problem HNC (Hochbaum’s Normalized Cut), which is similar to the Normalized Cut problem of Shi and Malik, a well known problem in image segmentation. HNC identifies cells as coherent clusters of pixels that are highly distinct from the remaining pixels. HNCcorr guarantees a globally optimal solution to the underlying optimization problem as well as minimal dependence on initialization techniques. HNCcorr also uses a new method, called “similarity squared”, for measuring similarity between pixels in calcium-imaging movies. The effectiveness of HNCcorr is demonstrated by its top performance on the Neurofinder cell identification benchmark. We believe HNCcorr is an important addition to the toolbox for analysis of calcium-imaging movies.</jats:p