BackgroundHydatidiform moles occur in approximately 1 in 1,500 pregnancies; however, early miscarriages or spontaneous abortions may not be correctly identified as molar pregnancies due to poor differentiation of chorionic villi.MethodsThe current clinical testing algorithm used for the detection of hydatidiform moles uses a combination of morphological analysis and p57 immunostaining followed by ploidy testing to establish a diagnosis of either a complete or partial molar pregnancy. We review here 198 referrals for fluorescence in situ hybridization (FISH) ploidy testing, where the initial diagnosis based on morphology is compared to the final diagnosis based on a combination of morphology, FISH and p57 immunohistochemical (IHC) staining.ResultsApproximately 40% of cases were determined to be genetically abnormal, but only 28.8% of cases were diagnosed as molar pregnancies. The underestimation of complete molar pregnancies and those with androgenetic inheritance was also found to be likely using conventional diagnostic methods, as atypical p57 staining was observed in approximately 10% of cases.ConclusionsOur findings suggest that a revised approach to testing products of conception is necessary, with cases screened according to their clinical history in order to distinguish molar pregnancy referrals from hydropic pregnancies.

Abstract. The aim of the present study was to evaluate the use of KaryoLite™ bacterial artificial chromosomes (BACs)-on-Beads™ (BoBs) technology for the rapid screening of products of conception (POC). Validation and prospective studies were carried out on 85 and 95 patient samples, respectively. Validation studies had previously been analyzed using routine culture and G-banded karyotyping. BoBs resulted in an abnormality detection frequency of 27%, with a failure rate of <3%. The time required for processing was significantly lower compared with that of tissue culture. In conclusion, BoBs technology decreased the failure rate, while increasing the analytical sensitivity compared with G-banded karyotype analysis alone. Additionally, significant cost savings may be achieved with regard to the time of processing and analysis of

The recent publication of the genome sequence of the sea urchin, Strongylocentrotus purpuratus, has highlighted the deficiency of information about the cytogenetics of echinoderms. As the issue of numerical variation and chromosome stability in echinoderms has long been a source of dispute, the hypothesis of chromosomal stability needs to be tested with a wider range of species from diverse regions of the world. Here we have compiled a table of published echinoderm chromosome numbers and provide new data from the southern hemisphere echinoid species, Evechinus chloroticus. Analysis of E. chloroticus embryos taken from six different male-female urchin pairs showed a modal chromosome count of 2n = 42, as predicted by the chromosome stability hypothesis. However, a high degree of chromosomal variation was observed between individuals, with chromosome numbers ranging from 17 to 80. While there was no significant difference in mean chromosome number between all six parental combinations, there was a significant difference in mean chromosome number between embryos taken from two different urchin pairs for which intraembryo analysis was possible. These results indicate that extensive chromosomal variation can arise within embryos, and may also differ between individual urchin pairs. However, the extent to which methodological issues may contribute to the observed variation is unclear, and further research will be required to determine whether such variability is present within natural populations.

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The major structural lesions of the human brain during aging and in Alzheimer disease (AD) are the neurofibrillary tangles (NFT) and the senile (neuritic) plaque. Although these fibrous alterations have been recognized by light microscopists for almost a century, detailed biochemical and morphological analysis of the lesions has been undertaken only recently. Because the intraneuronal deposits in the NFT and the plaque neurites and the extraneuronal amyloid cores of the plaques have a filamentous ultrastructure, the neuronal cytoskeleton has played a prominent role in most pathogenetic hypotheses.The approach of our laboratory toward elucidating the origin of plaques and tangles in AD has been two-fold: the use of analytical protein chemistry to purify and then characterize the pathological fibers comprising the tangles and plaques, and the use of certain monoclonal antibodies to neuronal cytoskeletal proteins that, despite high specificity, cross-react with NFT and thus implicate epitopes of these proteins as constituents of the tangles.