Search results for "bryology"
showing 10 items of 206 documents
09-P102 Somitogenesis and development of primary motor neurons: The role of the homeobox uncx4.1
2009
The gene uncx4.1 is a paired-type homeobox transcription factor, expressed during zebrafish embryonic development in branchial arches, somites, CNS and pronephric ducts. In particular, the expression at the somite level is detectable from 5ss stage and becomes progressively posteriorly and ventrally restricted to the presumptive myoblast cells in later stages. Interestingly, the progressive restriction of uncx4.1 activity anticipates and accompanies the appearance of the first outgrowing primary motor axons. Indeed, after uncx4.1 expression is not detected anymore in medial somitic cells, a ventrally projecting CaP motor axons emerge from the ventro-lateral spinal cord. In relation with mus…
Effects of electrical stimulation of the superior cervical ganglia on the number of ?synaptic? ribbons and the activity of melatonin-forming enzymes …
1989
Melatonin metabolism in the mammalian pineal gland is under the clear influence of sympathetic fibers originating in the superior cervical ganglia (SCG). Previous studies suggested that pineal "synaptic" ribbons (SR) as well are regulated by the gland's sympathetic innervation. To gain more insight into the mechanisms involved, we examined the effects of sympathetic stimulation on SR number and on the activity of melatonin forming enzymes, serotonin N-acetyltransferase (NAT) and hydroxyindole-O-methyltransferase (HIOMT). The SCG in adult male rats were stimulated electrically during daytime for either 15 or 120 min. Immediately following stimulation, the glands were removed and processed fo…
CXCL10 and IL-6 induce chemotaxis in human trophoblast cell lines.
2008
The investigation of trophoblast chemoattractive molecules in humans is of high interest for the reproductive field. Current evidence in ruminants demonstrates that CXCL10, formerly the interferon-gamma-inducible protein 10 (IP-10), is a potent chemotactic molecule implicated in the migration of trophoblast cells during early gestation. The aim of this work was to explore the existence of CXCL10/CXCR3 in the human model. Furthermore, chemotaxis assays were performed to demonstrate CXCL10 chemotactic activity in the human trophoblast cell lines JEG-3 and AC-1M88. Surprisingly, the conditioned media from epithelial endometrial cells (EEC) induced the highest trophoblast migration rate. Cytoki…
Quantitative methylation analysis of developmentally important genes in human pregnancy losses after ART and spontaneous conception.
2009
To study possible effects of assisted reproductive technologies (ART) on epigenetic reprogramming, we have analyzed the DNA methylation levels of differentially methylated regions (DMRs) of seven imprinted genes (H19, MEG3, LIT1, MEST, NESP55, PEG3 and SNRPN) as well as the promoter regions of the pluripotency gene NANOG and the tumor suppressor gene APC in chorionic villus samples (CVS) of 42 spontaneous miscarriages and stillbirths after ART and 29 abortions/stillbirths after spontaneous conception. We did not find an increased rate of faulty methylation patterns after ART, but significant and trend differences (ROC curve analysis, Wilcoxon test) in the methylation levels of LIT1 (P = 0.0…
Does Uterine Doppler Add Information to the Cerebroplacental Ratio for the Prediction of Adverse Perinatal Outcome at the End of Pregnancy?
2019
<b><i>Objective:</i></b> To evaluate whether the addition of the mean uterine arteries pulsatility index (mUtA PI) to the cerebroplacental ratio (CPR) improves its ability to predict adverse perinatal outcome (APO) at the end of pregnancy. <b><i>Methods:</i></b> This was a prospective study of 891 fetuses that underwent an ultrasound examination at 34–41 weeks. The CPR and the mUtA PI were converted into multiples of the median (MoM) and the estimated fetal weight (EFW) into centiles according to local references. APO was defined as a composite of abnormal cardiotocogram, intrapartum pH requiring cesarean section, 5′ Apgar score &#x3c;7, n…
Can novel early non-invasive biomarkers of embryo quality be identified with time-lapse imaging to predict live birth?
2019
AbstractSTUDY QUESTIONCan time-lapse imaging systems make it possible to identify novel early non-invasive biomarkers to predict live birth?SUMMARY ANSWERFrom mostly high-grade embryos, out of 35 morphometric, morphologic and morphokinetic variables, only pronuclei (PN) position at time of PN juxtaposition and the absence of multinucleated blastomeres at the 2-cell stage (MNB2cell), were potentially associated with live birth.WHAT IS KNOWN ALREADYPrevious studies indicate that some kinetic markers may be predictive of blastocyst development and embryonic implantation. Certain teams have suggested including some of them in decisional algorithms for embryo transfers.STUDY DESIGN, SIZE, DURATI…
Potential effects of age-associated oxidative stress on mammalian oocytes/embryos
1996
This bioessay aims to explain the different effects of maternal ageing and postovulatory oocyte ageing on mammalian oocytes/embryos under the scope of 'the oxygen radical-mitochondrial injury hypothesis of ageing'. This hypothesis assumes a key role in the senescent process of oxygen radical damage to mitochondrial DNA, proteins and lipids. It is proposed that a decrease in intracellular ATP concentrations and glutathione (GSH)/glutathione disulphide (GSSG) ratio together with a concomitant increase in cytosolic Ca2+ are major factors causing the observed detrimental effects of ageing on cytoskeletal fibres, fertilization and embryo development.
Second study on the recurrence risk of isolated esophageal atresia with or without trachea-esophageal fistula among first-degree relatives: no eviden…
2013
BACKGROUND Esophageal atresia with/without trachea-esophageal fistula (EA/TEF) denotes a spectrum of severe congenital malformations. The aim of this systematic study was to determine both the recurrence risk for EA/TEF, and the risk for malformations of the VATER/VACTERL association spectrum, in first-degree relatives of patients with isolated EA/TEF. METHODS A total of 108 unrelated patients with isolated EA/TEF were included. These individuals had 410 first-degree relatives including 194 siblings. The presence of EA/TEF and malformations of the VATER/VACTERL association spectrum in relatives was systematically assessed. Data from the EUROCAT network were used for comparison. RESULTS None…
Endometrial gene expression analysis at the time of embryo implantation in women with unexplained infertility
2009
Successful embryo implantation depends on the quality of the embryo, as well as on the receptivity of the endometrium. The aim of this study was to investigate the endometrial gene expression profile in women with unexplained infertility in comparison with fertile controls at the time of embryo implantation in order to find potential predictive markers of uterine receptivity and to identify the molecular mechanisms of infertility. High-density oligonucleotide gene arrays, comprising 44 000 gene targets, were used to define the endometrial gene expression profile in infertile (n = 4) and fertile (n = 5) women during the mid-secretory phase (day LH + 7). Microarray results were validated usin…
Quantitative investigations on the human entorhinal area: left-right asymmetry and age-related changes
1994
The total nerve cell numbers in the right and in the left human entorhinal areas have been calculated by volume estimations with the Cavalieri principle and by cell density determinations with the optical disector. Thick gallocyanin-stained serial frozen sections through the parahippocampal gyrus of 22 human subjects (10 female, 12 male) ranging from 18 to 86 years were analysed. The laminar composition of gallocyanin (Nissl)-stained sections could easily be compared with Braak's (1972, 1980) pigmentoarchitectonic study, and Braak's nomenclature of the entorhinal laminas was adopted. Cell-sparse laminae dissecantes can more clearly be distinguished in Nissl than in aldehydefuchsin preparati…