Chromosome analysis in polyploid human embryos

Cytogenetic investigations have been performed on 436 unfertilized or polyploid human oocytes after in-vitro fertilization at the Department of Obstetrics and Gynaecology, University of Kiel. Thirty-two oocytes had more than two pronuclei 16-20 h after fertilization and were therefore potentially the precursors of polyploid embryos. The total number of fertilized oocytes was 667, and the frequency of tripronucleate ova was 4.8%. These tripronucleate eggs may develop normally up to birth but never lead to viable newborn children. Some of the resulting embryos displayed chromosomal mosaicism, where polyploid karyotypes and normal diploid cells occurred together. It is assumed that the survival rate of polyploid embryos depends upon the percentage of normal diploid cell

Application of functional genomics to primate endometrium: insights into biological processes

Endometrium is a dynamic tissue that responds on a cyclic basis to circulating levels of the ovarian-derived steroid hormones, estradiol and progesterone. Functional genomics has enabled a global approach to understanding gene regulation in whole endometrial tissue in the setting of a changing hormonal milieu. The proliferative phase of the cycle, under the influence of estradiol, has a preponderance of genes involved in DNA synthesis and cell cycle regulation. Interestingly, genes encoding ion channels and cell adhesion, as well as angiogenic factors, are also highly regulated in this phase of the cycle. After the LH surge, different gene expression profiles are uniquely observed in the early secretory, mid-secretory (window of implantation), and late secretory phases. The early secretory phase is notable for up-regulation of multiple genes and gene families involved in cellular metabolism, steroid hormone metabolism, as well as some secreted glycoproteins. The mid-secretory phase is characterized by multiple biological processes, including up-regulation of genes encoding secreted glycoproteins, immune response genes with a focus on innate immunity, and genes involved in detoxification mechanisms. In the late secretory phase, as the tissue prepares for desquamation, there is a marked up-regulation of an inflammatory response, along with matrix degrading enzymes, and genes involved in hemostasis, among others. This monograph reviews hormonal regulation of gene expression in this tissue and the molecular events occurring therein throughout the cycle derived from functional genomics analysis. It also highlights challenges encountered in using human endometrial tissue in translational research in this context

Stress responses in alfalfa (Medicago sativa L.) XIX. Transcriptional activation of oxidative pentose phosphate pathway genes at the onset of the isoflavonoid phytoalexin response

Article on stress responses in alfalfa (Medicago sativa L.) XIX and transcriptional activation of oxidative pentose phosphate pathway genes at the onset of the isoflavonoid phytoalexin response

Strong interference effects in the angularly resolved Auger decay and fluorescence emission spectra of the core excited NO molecule

International audienceAngular distributions of the Auger electrons and subsequent fluorescence photons are studied theoretically and experimentally in the vicinity of the core excitations of NO. In the calculations, lifetime vibrational interference and electronic states interference were taken into account ab initio. The interference between excitation-deexcitation amplitudes for transitions via symmetry different intermediate resonances 1s −1 2π 2 (2 ∆, 2 Σ ±), which is forbidden in the solid-angle-averaged or magic-angle-recorded decay spectra, plays a crucial role in the formation of the angularly resolved decay spectra. Experimentally, angular distribution parameters for the NO + A 1 Π → X 1 Σ + fluorescence induced by linearly polarized synchrotron radiation are determined in the vicinity of the N * O resonance in the Raman regime for core excitation. Theoretical results are in good agreement with the present experimental fluorescence spectra and with available vibrationally and angularly resolved resonant Auger electron spectra