Search results for "Embryonic Structures"
showing 10 items of 623 documents
Sonographische Diagnose eines Holoakardius
2008
In the 28th week of gestation a normal foetus and a holoacardius were diagnosed via sonography in a biamnotic monochoriatic twin pregnancy. The growth of the foetuses was observed under continuous sonographic control up to the 40th week of pregnancy. The patient delivered a healthy twin by Caesarean section and the acardius was subjected to a postmortem. Macroscopic and histological findings in the foetus, the placenta and the umbilical cords are demonstrated. The pathogenesis of the holoacardius is discussed as being due to chromosomal aberrations and foeto-foetal transfusion syndrome.
Effects of prandial glycemic changes on objective fetal heart rate parameters
2000
Background. There is confusion in the literature about the potential effect of maternal glucose levels on the fetal heart rate (FHR) cardiotocographic interpretation.Methods. Study design: prospective clinical descriptive study. Subjects: 21 pregnant women with diabetes mellitus, 23 women with gestational diabetes and 18 healthy non-diabetic pregnant volunteers (control group). Treatment: maternal capillary glucose measurement and objective FHR analysis (Oxford System 8002) pre- and 1 h post-meal. Statistical analysis: descriptive statistics, Student t-tests and Pearson correlation studies.Results. Maternal capillary glucose levels ranged between 2.7–10.5 mmol/l pre-meal and 4.2–14.8 mmol/l…
Influence of hydrocortisone on chick embryo retina development
1987
Treatment of chick embryos in ovo with hydrocortisone-21-phosphate (a single dose of 150 micrograms) caused a marked reduction of retinal thymidine kinase activity 24 h later. The inhibitory effect was highest (65-70%) in 8-10-day-old embryos and declined with age, disappearing after day 15. It was accompanied by a reduction in thickness of the retinal layers. Adrenocorticotropic hormone (ACTH) treatment (10 micrograms daily for 2 days) also produced an age-dependent inhibitory effect on retinal thymidine kinase, whereas treatment with a single dose of 200 micrograms of metopirone, a compound that prevents the 11 beta-hydroxylation of steroid molecules in the adrenal glands, impeded the dec…
Signaling through BMPR-IA regulates quiescence and long-term activity of neural stem cells in the adult hippocampus.
2010
SummaryNeural stem cells (NSCs) in the adult hippocampus divide infrequently, and the molecules that modulate their quiescence are largely unknown. Here, we show that bone morphogenetic protein (BMP) signaling is active in hippocampal NSCs, downstream of BMPR-IA. BMPs reversibly diminish proliferation of cultured NSCs while maintaining their undifferentiated state. In vivo, acute blockade of BMP signaling in the hippocampus by intracerebral infusion of Noggin first recruits quiescent NSCs into the cycle and increases neurogenesis; subsequently, it leads to decreased stem cell division and depletion of precursors and newborn neurons. Consistently, selective ablation of Bmpr1a in hippocampal …
MUCI, glycans and the cell-surface barrier to embryo implantation
2001
As it approaches the maternal surface, the attaching embryo encounters the epithelial glycocalyx, which contains the mucin, MUC1. A high density of MUC1 at the cell surface can inhibit cell adhesion. This raises the possibility of the existence of a uterine barrier to implantation that might allow maternal rejection of poorer quality embryos. To investigate the mechanism of implantation, human embryos were incubated with endometrial epithelial monolayers. Hatched blastocysts were found to attach readily to the epithelial surface. MUC1 was lost from epithelial cells beneath and near to the attached embryo, while normal expression persisted in neighbouring cells.
Abnormal development of pacinian corpuscles in double trkB;trkC knockout mice.
2006
Pacinian corpuscles depend on either Aalpha or Abeta nerve fibers of the large- and intermediate-sized sensory neurons for the development and maintenance of the structural integrity. These neurons express TrkB and TrkC, two members of the family of signal transducing neurotrophin receptors, and mice lacking TrkB and TrkC lost specific neurons and the sensory corpuscles connected to them. The impact of single or double targeted mutations in trkB and trkC genes in the development of Pacinian corpuscles was investigated in 25-day-old mice using immunohistochemistry and ultrastructural techniques. Single mutations on trkB or trkC genes were without effect on the structure and S100 protein expr…
Ovicidal Activity of Maternally Applied Ecdysteroids in the Large Milkweed Bug (Heteroptera: Lygaeidae)
1982
Exogenous ecdysteroids (ecdysone, 20-hydroxyecdysone and makisterone A) administered to reproducing females of Oncopelus fasciatus (Dallas) reduced egg hatch drastically. The ovicidal activity apparently stemmed from ecdysteroids—unchanged hormone or metabolites—transferred from mother into oocyte. Different stages of embryogenesis were affected. Makisterone A, the predominant ecdysteroid in normal embryos, is by far the most effective ecdysteroid.
0201: Cardiac surgery associated with cardiopulmonary bypass in patients with stable coronary disease: growth differentiation factor-15 (GDF- 15) as …
2014
BackgroundGrowth differentiation factor-15 (GDF-15) has been identified as a strong marker for cardiovascular disease; however, no data are available concerning the role of GDF-15 in the occurrence of organ dysfunction during cardiac surgery associated with cardiopulmonary bypass (CPB).MethodsThirty four patients, programmed to have non-urgent coronary artery bypass grafting (CABG), were included in our study. Arterial blood samples were taken sequentially from anesthesia induction (IND) until 24h after arrival at the cardiovascular intensive care unit (ICU). Plasma levels of GDF-15, follistatin-like 1 (FLST1), myeloperoxidases (MPO), hydroperoxides and plasma antioxidant status (PAS) were …
Programming of neural progenitors of the adult subependymal zone towards a glutamatergic identity by Neurogenin2
2017
ABSTRACTWhile the adult subependymal zone (SEZ) harbors pools of distinct neural stem cells that generate different types of GABAergic interneurons, a small progenitor population in the dorsal SEZ expresses Neurog2 and gives rise to glutamatergic neurons. Here we investigated whether SEZ progenitors can be programmed towards glutamatergic neurogenesis through forced expression of Neurog2. Retrovirus-mediated expression of Neurog2 induced the glutamatergic neuron lineage markers Tbr2 and Tbr1 in cultured SEZ progenitors which subsequently differentiated into functional glutamatergic neurons. Likewise, retrovirus-mediated expression of Neurog2 in dividing SEZ progenitors within the adult SEZ …
Antiphosphatidylserine Antibodies Affect Rat Yolk Sacs in Culture: a Mechanism for Fetal Loss in Antiphospholipid Syndrome
2004
PROBLEM: A variety of reproductive impairments have been reported in the context of the antiphospholipid syndrome (APS). APS is associated with the presence of antibodies to negatively charged phospholipids that may affect the outcome of pregnancy. METHOD OF STUDY: Rat embryos were cultured within their yolk sacs. The effects of two antiphosphatidylserine monoclonal aPS antibodies (HL5B, RR7F) regarding their influence on growth and apoptotic events of the yolk sacs, as well as on growth and the morphology of the embryos, were studied. RESULTS: Exposure of rat embryos and their yolk sacs to aPS inhibited yolk sac growth. Moreover, increased number of apoptotic events of giant cells in the a…