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Maternal Cells (maternal + cell)
Selected AbstractsLarval development in the Homoscleromorpha (Porifera, Demospongiae)INVERTEBRATE BIOLOGY, Issue 3 2003Nicole Boury-Esnault Abstract. Embryonic development from coeloblastula to fully developed larva was investigated in 8 Mediterranean homoscleromorph species: Oscarella lobularis, O. tuberculata, O. microlobata, O. imperialis, Plakina trilopha, P. jani, Corticium candelabrum, and Pseudocorticium jarrei. Morphogenesis of the larva is similar in all these species; however, cell proliferation is more active in species of Oscarella than in Plakina and C. candelabrum. The result of cell division is a wrinkled, flagellated larva, called a cinctoblastula. It is composed of a columnar epithelium of polarized, monoflagellated cells among which are scattered a few non-flagellated ovoid cells. The central cavity always contains symbiotic bacteria. Maternal cells are also present in O. lobularis, O. imperialis, and P. jarrei. In the fully developed larva, cell shape and dimensions are constant for each species. The cells of the anterior pole have large vacuoles with heterogeneous material; those of the postero-lateral zone have an intranuclear paracrystalline inclusion; and the flagellated cells of the posterior pole have large osmiophilic inclusions. Intercellular junctions join the apical parts of the cells, beneath which are other specialized cell junctions. A basement membrane underlying the flagellated cells lines the larval cavity. This is the first observation of a basement membrane in a poriferan larva. The basal apparatus of flagellated cells is characterized by an accessory centriole located exactly beneath the basal body. The single basal rootlet is cross striated. The presence of a basement membrane and a true epithelium in the larva of Homoscleromorpha,unique among poriferan clades and shared with Eumetazoa,suggests that Demospongiae could be paraphyletic. [source] Maternal cells are not resp for erythema tox neonPEDIATRIC DERMATOLOGY, Issue 3 2008CATHERINE DROITCOURT M.D. Letters to the Editor are welcomed for publication (subject to editing). Letters must be signed by all authors, typewritten double spaced, and must not exceed two pages of text including references. Two copies of all letters should be submitted along with one copy on disk. Letters should not duplicate material submitted or published in other journals. Prepublication proofs will not be provided. [source] The utility of an erythroblast scoring system and gender-independent short tandem repeat (STR) analysis for the detection of aneuploid fetal cells in maternal bloodPRENATAL DIAGNOSIS, Issue 7 2005Dong Hyun Cha Abstract Objective The aim of this study was to determine whether fetal nucleated red blood cells (NRBCs) could be distinguished from maternal cells in peripheral blood using an erythroblast scoring system based on the unique morphological and hemoglobin staining characteristics of this cell type. Presumptive fetal NRBCs were further analyzed for the presence of paternally inherited DNA polymorphisms to prove fetal origin. Methods NRBCs were isolated by density gradient separation, CD15/45 depletion, and gamma hemoglobin positive selection from peripheral blood of nine women following termination of pregnancy for trisomy 21 (n = 4), 18 (n = 1), 13 (n = 2), and other genetic abnormalities (n = 2). Candidate fetal NRBCs, based on four discrete morphological and hemoglobin staining criteria, were then subjected to fluorescent PCR (polymerase chain reaction) amplification of chromosome 21 (D21S1411, D21S11) and chromosome 18 (D18S535) short tandem repeat (STR) DNA polymorphisms. Results In all cases, candidate fetal NRBCs were accurately identified on the basis of morphologic and hemoglobin staining characteristics and confirmed to be fetal in origin based on the presence of shared and nonshared polymorphic DNA alleles when compared to DNA isolated from maternal cells. Conclusions Using the erythroblast scoring system and subsequent analysis of inherited DNA polymorphisms, we were able to distinguish fetal NRBCs from maternal cells and prove fetal origin independent of gender. These results suggest that this novel combined approach to fetal cell isolation and genetic analysis is a promising method for noninvasive prenatal diagnostic applications. Copyright © 2005 John Wiley & Sons, Ltd. [source] Applying a test system for discriminating fetal from maternal cellsPRENATAL DIAGNOSIS, Issue 8 2003nar Bayrak-Toydemir Abstract Objective The objectives of this study were to enhance and apply a simple system capable of testing the capacity of putative, gender-independent fetal cell markers, individually and in combination, to discriminate between fetal and maternal cells. Methods Chorionic villi tissue obtained from 25 male pregnancies at 10 to 12 weeks' gestation served as the experimental group. Following removal of villi pieces for clinical use, unattached cells were collected by centrifugation of the CVS fluid, fixed in the tube, and used as a source of mixed fetal and maternal cells. Blood obtained from a fetus at 13 weeks' gestation served as a positive control. Peripheral blood from two adult males served as negative controls. Antibodies to three possible fetal markers were tested using immunohistochemical techniques: anti-Flk-1, anti-epsilon globin, and anti-CD71. Each antibody was used alone and in combination in conjunction with fluorescent in situ hybridization (FISH) of X and Y chromosomes to confirm that positively stained cells were in fact fetal in origin. Results On CVS samples, the average predictive value for anti-Flk-1 was 35.8%, 76.2% for anti-CD71, and 90.5% for anti-epsilon. The combination of anti-epsilon and anti-CD71 antibodies identifying a fetal cell was 87.2% and the combined use of single and double antibodies gave a value of 82.7%. The combination of anti-epsilon globin and anti-CD71 increased the sensitivity of identifying pure fetal blood cells from 63%, for anti-epsilon alone, and 67%, for anti-CD71 alone, to 86%. Conclusion Although anti-Flk-1 has been reported to be a successful marker of fetal cells, the results in this test system did not support this finding. This work supports the use of CVS washings containing both fetal and maternal cells as a viable test system for assessing antigenic markers. The combination of anti-CD71 and anti-epsilon as fetal identifiers may increase the chances of identifying a fetal cell without compromising the predictive value. Copyright © 2003 John Wiley & Sons, Ltd. [source] Cytogenetic analysis of trophoblasts by comparative genomic hybridization in embryo-fetal development anomaliesPRENATAL DIAGNOSIS, Issue 8 2001A. C. Tabet Abstract Cytogenetic studies of spontaneous abortions or intrauterine fetal death depend on conventional tissue culturing and karyotyping. This technique has limitations such as culture failure and selective growth of maternal cells. Fluorescent in situ hybridization (FISH) using specific probes permits diagnosis of aneuploidies but is limited to one or a few chromosomal regions. Comparative genomic hybridization (CGH) provides an overview of chromosomal gains and losses in a single hybridization directly from DNA samples. In a prospective study, we analyzed by CGH trophoblast cells from 21 fetuses in cases of spontaneous abortions, intrauterine fetal death or polymalformed syndrome. Six numerical chromosomal abnormalities including one trisomy 7, one trisomy 10, three trisomies 18, one trisomy 21 and one monosomy X have been correctly identified by CGH. One structural abnormality of the long arm of chromosome 1 has been characterized by CGH. One triploidy and two balanced pericentromeric inversions of chromosome 9 have not been identified by CGH. Sexual chromosomal constitutions were concordant by both classical cytogenetic technique and CGH. Contribution of trophoblast analysis by CGH in embryo-fetal development anomalies is discussed. Copyright © 2001 John Wiley & Sons, Ltd. [source] Embryonic development of verongid demosponges supports the independent acquisition of spongin skeletons as an alternative to the siliceous skeleton of spongesBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 2 2009MANUEL MALDONADO Approximately 85% of extant sponges (phylum Porifera) belong to the class Demospongiae, which contains 14 taxonomic orders. In the orders Verongida, Dictyoceratida, and Dendroceratida, jointly referred to as ,keratose demosponges', the skeleton does not contain siliceous spicules but only spongin fibres. This shared trait has encouraged placement of these orders together within Demospongiae, although their relationships remain uncertain. The present study documents for the first time embryo development in the order Verongida (Aplysina aerophoba), providing some clues for phylogenetic inference. Spawned eggs were enveloped by a follicle of maternal cells. Embryos and larvae were chimeric organisms, the blastocoel of which was filled with symbionts and maternal cells migrated from the follicle. The ultrastructure of epithelial larval cells revealed: (1) a basal apparatus characterized by a peculiar, angling accessory centriole; (2) a pear-shaped nucleus with a protruding beak connected to the rootlets of the basal body; and (3) a distinctive Golgi apparatus encircling the nuclear apex. Developmental and ultrastructural findings support the concept, in congruence with recent molecular studies, that Verongida are more closely related to Halisarcida (askeletal sponges) and Chondrosida (askeletal sponges + sponges with spongin + spiculate sponges) than to the remaining ,keratose' orders, making a monophyletic ,supra-ordinal unit' equivalent to a subclass (Myxospongia, new subclass). Hence, spongin skeletons have evolved at least twice in Demospongiae. Independent acquisition of ,corneous' materials as an alternative to silica could have been stimulated by the radiation of diatoms at the Cretaceous,Tertiary boundary (approximately 65 Mya), which depleted silicon in the photic zone of the world's ocean. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 97, 427,447. [source] | ||||||||||