EDD is the mammalian ortholog of the Drosophila melanogaster hyperplastic disc gene (hyd), which is critical for cell proliferation and differentiation in flies through regulation of hedgehog and ...decapentaplegic signaling. Amplification and overexpression of EDD occurs frequently in several cancers, including those of the breast and ovary, and truncating mutations of EDD are also observed in gastric and colon cancer with microsatellite instability. EDD has E3 ubiquitin ligase activity, is involved in regulation of the DNA damage response, and may control hedgehog signaling, but a definitive biological role has yet to be established. To investigate the role of Edd in vivo, gene targeting was used to generate Edd knockout (Edd super( delta / delta )) mice. While heterozygous mice had normal development and fertility, no viable Edd-deficient embryos were observed beyond E10.5, with delayed growth and development evident from E8.5 onward. Failed yolk sac and allantoic vascular development, along with defective chorioallantoic fusion, were the primary effects of Edd deficiency. These extraembryonic defects presumably compromised fetal-maternal circulation and hence efficient exchange of nutrients and oxygen between the embryo and maternal environment, leading to a general failure of embryonic cell proliferation and widespread apoptosis. Hence, Edd has an essential role in extraembryonic development.
The present study stemmed from a need for a rapid means of deriving reproducible chromosome measurements. An internal set of standards can serve as the basis for routine, easy, and reliable ...morphometric comparisons. In this study, a total of 100 karyotyped metaphases were analyzed using the Nestler Run-Mate, a computerized curvilinear measuring tool. The null hypothesis tested was that there are no significant differences between chromosomal relative-length values obtained via this previously untested approach and those cited in ISCN (1985). The results indicate that this new method is not only feasible and adequate but has advantage over the conventional approach, which requires the use of a projector and screen to measure chromosomes in unkaryotyped metaphase spreads; further, it is less expensive and easier than using computerized digitizing tablets, a conclusion supported by time-and-effort measurements. Immediately obvious applications include routine use in clinical cytogenetics laboratories, as well as for fractional length estimations in fluorescent in situ hybridization studies performed in research laboratories that do not have access to expensive automated instrumentation.
We present a search for nine lepton-number-violating and three lepton-flavor-violating neutral charm decays of the type \(D^0\rightarrow h^{\prime -} h^{-}\ell^{\prime +} \ell^{+}\) and ...\(D^0\rightarrow h^{\prime -} h^{+}\ell^{\prime\pm} \ell^{\mp}\), where \(h\) and \(h^{\prime}\) represent a \(K\) or \(\pi\) meson and \(\ell\) and \(\ell^{\prime}\) an electron or muon. The analysis is based on \(468\) fb\(^{-1}\) of \(e^+e^-\) annihilation data collected at or close to the \(Y(4S)\) resonance with the BaBar detector at the SLAC National Accelerator Laboratory. No significant signal is observed for any of the twelve modes and we establish 90% confidence level upper limits on the branching fractions in the range \((1.0 - 30.6)\times 10^{-7}\). The limits are between one and three orders of magnitude times more stringent than previous measurements.
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