Search results for "Embryogenesi"
showing 10 items of 190 documents
Insulin synthesis in chick embryo retinas during development.
1994
Retinas of chick embryos contain insulin (1) and further, are capable of synthesizing it, as demonstrated by incubating retinas at different ages (7th–18th day) with [3H]leucine. The synthesized radioactive insulin was isolated and assayed by means of a HPLC procedure. The synthesis of insulin was found to be highest in the youngest retinas studied (day 7), afterwards it declined with age except for an increment found at 14–15 day. Explants of chick embryo retinas, cultured in vitro, rapidly degraded insulin. Nevertheless, the content of immunoreactive insulin in retinal explants diminished slowly with the age of culture, so that, after 8 days of incubation, it was about 60% of the content …
Embryonic and foetal Islet-1 positive cells in human hearts are also positive to c-Kit.
2011
During embryogenesis, the mammalian heart develops from a primitive heart tube originating from two bilateral primary heart fields located in the lateral plate mesoderm. Cells belongings to the pre-cardiac mesoderm will differentiate into early cardiac progenitors, which express early transcription factors which are also common to the Isl-1 positive cardiac progenitor cells isolated from the developing pharyngeal mesoderm and the foetal and post-natal mice hearts. A second population of cardiac progenitor cells positive to c-Kit has been abundantly isolated from adult hearts. Until now, these two populations have been considered two different sets of progenitor cells present in the heart in…
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.
Cardiac pacemaker function of HCN4 channels in mice is confined to embryonic development and requires cyclic AMP.
2008
Important targets for cAMP signalling in the heart are hyperpolarization-activated and cyclic nucleotide-gated (HCN) channels that underlie the depolarizing 'pacemaker' current, I(f). We studied the role of I(f) in mice, in which binding of cAMP to HCN4 channels was abolished by a single amino-acid exchange (R669Q). Homozygous HCN4(R669Q/R669Q) mice die during embryonic development. Prior to E12, homozygous and heterozygous embryos display reduced heart rates and show no or attenuated responses to catecholaminergic stimulation. Adult heterozygous mice display normal heart rates at rest and during exercise. However, following beta-adrenergic stimulation, hearts exhibit pauses and sino-atrial…
A time to look back: analysis of morphokinetic characteristics of human embryo development.
2013
Objective To describe the times associated with the morphological changes that occur in the embryo during preimplantation development based on the largest sample size described with time lapse. Design Cohort study. Setting University-affiliated private center. Patient(s) A total of 9,530 embryos from 1,806 intracytoplasmic sperm injection (ICSI) cycles. Intervention(s) None. Main Outcome Measure(s) Using a time-lapse system, embryo images were acquired for at least 68 hours, in some cases reaching 120–130 hours. Embryo cleavage time points up to 8-cell-stage (t2–t8) as well as morulae (tM) and blastocyst formation (tB) were registered in hours after ICSI. Additionally, duration of the cell …
Consequences of analgesics use in early pregnancy: Results of tests on mice.
2019
International audience; Self-medication during pregnancy continues to be an issue in developing countries due topoor medical education. The most commonly used drugs are analgesics, mainlyacetaminophen (paracetamol, APAP) and, to a lesser extent, ketoprofen (KPF). The aim of thestudy was to establish whether there are consequences of accidental use of these two drugsduring early embryogenesis. The experimental study was performed on 30 pregnant whitemice, divided into three groups: a first group to which APAP was administered, a secondgroup to which KPF was administered, and group 3 as a control group. At delivery, the babymice were examined, and after their first parturition, they were take…
First stages of microspore reprogramming to embryogenesis through anther culture in Prunus armeniaca L
2009
Molecular Network Establishing Dorsal-Ventral polarity during sea urchin embryogenesis
2015
Somatic Embryogenesis and Plant Regeneration from Hypocotyl Cultures of Digitalis obscura L.
1986
Summary Hypocotyl sections from 20-day-old seedlings of Digitalis obscura L. were used to examine the effect of IAA on somatic embryogenesis. Although embryogenesis was obtained with all IAA concentrations (0.1, 0.5 and 1 ppm) and under both illumination conditions tested (16 h photoperiod and darkness), incubation in photoperiod increased yield of embryos and shortened the embryo induction time. Optimum results were obtained with 1 ppm IAA. About 30 % of the embryos obtained developed into complete plantlets when transferred to basal medium without growth regulators.