Initiation of placentation in the pig

The microscopic structure of the mature placenta in domesticated species has been described in many publications but the early developmental stages have only been studied in detail within the past decade. The earliest date previously cited for initial attachment of the porcine trophoblast to the maternal epithelium is 14 to 18 days of gestation. This investigation was undertaken to establish morphological changes in the maternal epithelium in preparation for this event.Four or 5 nulliparous gilts were slaughtered on each of d10 and d13 of the estrous cycle and pregnancy (d0=1st d of estrus), and tissue samples prepared for correlative light and electron microscopy. Samples were compared between gilts on equivalent days of the cycle/pregnancy in order to determine endometrial changes specific to pregnancy. Sites adjacent to embryos were contrasted with those lacking trophoblastic contact within the same animal to investigate whether epithelial adaptations for attachment are localized to trophoblast proximity or represent a generalized uterine response.

Early developmental stages of two actinosporeans, raabeia and aurantiactinomyxon (Myxozoa), as detected by light and electron microscopy

Journal of Invertebrate Pathology ◽

10.1016/s0022-2011(02)00007-1 ◽

2002 ◽

Vol 79 (1) ◽

pp. 17-26 ◽

Cited By ~ 8

Author(s):

M. Oumouna ◽

S.L. Hallett ◽

R.W. Hoffmann ◽

M. El-Matbouli

Keyword(s):

Electron Microscopy ◽

Developmental Stages ◽

Light And Electron Microscopy ◽

Hypothyroidism alters mitochondrial morphology and induces release of apoptogenic proteins during rat cerebellar development

Journal of Endocrinology ◽

10.1677/joe.0.1760321 ◽

2003 ◽

Vol 176 (3) ◽

pp. 321-329 ◽

Cited By ~ 23

Author(s):

R Singh ◽

G Upadhyay ◽

MM Godbole

Keyword(s):

Electron Microscopy ◽

Structural Analysis ◽

Developmental Stages ◽

Cerebellar Development ◽

Mitochondrial Morphology ◽

Mitochondrial Structure ◽

Proteolytic Cascade ◽

Apoptosis Inducing Factor ◽

Thyroid hormone (TH) deficiency leads to extensive apoptosis during cerebellar development, but the mechanism still remains unclear. Different signals also converge on mitochondria during apoptosis to induce the release of apoptogenic proteins that activate proteolytic cascade through specific enzymes called caspases. Here we studied the effect of hypothyroidism on alterations in mitochondrial structure and translocation of apoptogenic molecules during rat cerebellar development. Structural analysis of mitochondria was studied by electron microscopy. The translocation of apoptogenic molecules was analyzed by Western blotting. TH deficiency led to vacuolization, enlargement and decrease in the number of cristae. The majority of the proapoptotic molecule, Bax, was localized in mitochondria under hypothyroid conditions whereas a limited presence of Bax was detected in the euthyroid state. Translocation of cytochrome c, apoptosis-inducing factor (AIF) and second mitochondrial-derived activator of caspases (SMAC) from mitochondria to cytosol was detected primarily in early developmental stages in the hypothyroid condition. These experimental results demonstrate that TH maintains mitochondrial architecture and inhibits the release of apoptogenic molecules to prevent excess apoptosis during cerebellar development.

Effect of caffeine on Alzheimer’s molecular factors in correlation with involved cell communication systems in developing zebrafish Danio rerio

LaboratoriumsMedizin ◽

10.1515/labmed-2015-0028 ◽

2015 ◽

Vol 39 (3) ◽

Author(s):

Tamer Said Abdelkader ◽

Seo-Na Chang ◽

Ji-Min Lee ◽

JuHa Song ◽

Hanseul Oh ◽

...

Keyword(s):

Communication Systems ◽

Therapeutic Agent ◽

Developmental Stages ◽

Morphological Changes ◽

Molecular Genetic ◽

Cell Communication ◽

Epidemiological Studies ◽

And Control ◽

AbstractEpidemiological studies suggested that caffeine/coffee could be an effective therapeutic agent against Alzheimer disease (AD). The mechanism has not been well established; however, molecular genetic analyses suggest that many genes influence it.Using developing zebrafish (All genes are already expressed at early developmental stages. No morphological changes were found at tested concentrations and control. Caffeine significantly down-regulated the expression of all AD tested genes at 24 h post-fertilization (hpf) and APP, Sorl1, and Psen1 at 96 and 168 hpf. AZebrafish is a promising organism in studying AD at the molecular level because all tested factors are already expressed at early developmental stages. Caffeine has a regulatory effect on all tested genes and may protect against the disease via amyloid pathway as well as AR and DR.

Floral Organogenesis in Three Members of the Tribe Delphinieae (Ranunculaceae)

Plants ◽

10.3390/plants8110493 ◽

2019 ◽

Vol 8 (11) ◽

pp. 493 ◽

Cited By ~ 1

Author(s):

Chang ◽

Downie ◽

Peng ◽

Sun

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Developmental Stages ◽

Floral Organogenesis ◽

Early Developmental ◽

Scanning Electron

Three species (Aconitum taipeicum, Delphinium giraldii, and Consolida ajacis) of the tribe Delphinieae (Ranunculaceae) were examined using scanning electron microscopy and histological methods. The results showed that members of Delphinieae differ from their polysymmetrical relatives by four unique features: (1) a spiral phyllotaxis of their perianth and stamens, and a series of carpels, which initiated superficially in a whorl-liked arrangement; (2) sepal 2 being the largest one among the five sepals and becoming helmet-shaped or having a spur; (3) petals 2 and 5 initiated adaxially of sepal 2 and also becoming spurred; and (4) the monosymmetry of the first flower becoming established when sepal 2 becomes the largest. Major differences among the species include the timing of development of the second series; the fusion of two petals into a single one in C. ajacis; and, during early developmental stages, the two young spurred petals giving rise to a stalk and two bulges in A. taipeicum, a single bulge in D. giraldii, or an arch blade in C. ajacis. The unequal growth of the perianth, together with the reduction and the rearrangement of the carpels, are critical in inducing the symmetrical transformation of the flowers.

A revised ontogeny of the early Ordovician trilobite Leptoplastides salteri (Callaway, 1877)

Earth and Environmental Science Transactions of the Royal Society of Edinburgh ◽

10.1017/s1755691018000841 ◽

2018 ◽

Vol 111 (1) ◽

pp. 1-16

Author(s):

Kristina MÅNSSON ◽

Euan N. K. CLARKSON

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

New Technologies ◽

Developmental Stages ◽

New Information ◽

Time Scanning ◽

Contour Fitting ◽

Early Developmental ◽

Scanning Electron

ABSTRACTThe ontogeny of the pelturine olenid trilobite Leptoplastides salteri (Callaway, 1877) from the Shineton Shales, Shropshire, England, was first described in 1925 by Frank Raw. Since that time, scanning electron microscopy and other new technologies have revealed many more details of structure, of early developmental stages in particular, than were available to Raw. Whereas protaspides are not preserved and the state of preservation is less than perfect for the smallest meraspides, we have established that the latter had an array of delicate, long thoracic and pygidial spines, as well as paired procranidial spines, which disappear by meraspid degree 8. Raw's reconstructions of early meraspides, and his measurements of the early stages in development, are here amended in the light of new information. Dorsal spines in the adult are much more highly developed than have been documented in any other olenid. The hypostome is preserved in place in several specimens. Initially conterminant (attached to the doublure), it becomes natant (free) in late meraspid to early holaspid stages of development, with its anterior contour fitting exactly to that of the glabella. The ecology of the widespread Leptoplastides is best known from very extensive sections in South America, which provide a useful basis for comparison. It was well adapted to a range of environments, both oxygenated and dysoxic, and is usually the dominant taxon in the biofacies in which it is found.

Review of early developmental stages of trilobites and agnostids from the Barrandian area (Czech Republic)

Journal of the National Museum (Prague), Natural History Series ◽

10.2478/jzh-2018-0006 ◽

2017 ◽

Vol 186 (1) ◽

pp. 103-112

Author(s):

Lukáš Laibl ◽

Oldřich Fatka

Keyword(s):

Czech Republic ◽

Developmental Stages ◽

History Of Research ◽

History Of ◽

Barrandian Area ◽

This contribution briefly summarizes the history of research, modes of preservation and stratigraphic distribution of 51 trilobite and five agnostid taxa from the Barrandian area, for which the early developmental stages have been described.

The Effect of an Anthropogenic Magnetic Field on the Early Developmental Stages of Fishes—A Review

International Journal of Molecular Sciences ◽

10.3390/ijms22031210 ◽

2021 ◽

Vol 22 (3) ◽

pp. 1210

Author(s):

Krzysztof Formicki ◽

Agata Korzelecka-Orkisz ◽

Adam Tański

Keyword(s):

Magnetic Fields ◽

Developmental Stages ◽

Negative Influence ◽

Pigment Cells ◽

Egg Activation ◽

Industrial Equipment ◽

Positive Effects ◽

Species Specific ◽

The number of sources of anthropogenic magnetic and electromagnetic fields generated by various underwater facilities, industrial equipment, and transferring devices in aquatic environment is increasing. These have an effect on an array of fish life processes, but especially the early developmental stages. The magnitude of these effects depends on field strength and time of exposure and is species-specific. We review studies on the effect of magnetic fields on the course of embryogenesis, with special reference to survival, the size of the embryos, embryonic motor function, changes in pigment cells, respiration hatching, and directional reactions. We also describe the effect of magnetic fields on sperm motility and egg activation. Magnetic fields can exert positive effects, as in the case of the considerable extension of sperm capability of activation, or have a negative influence in the form of a disturbance in heart rate or developmental instability in inner ear organs.

Mitochondrial Processes during Early Development of Dictyostelium discoideum: From Bioenergetic to Proteomic Studies

Genes ◽

10.3390/genes12050638 ◽

2021 ◽

Vol 12 (5) ◽

pp. 638

Author(s):

Monika Mazur ◽

Daria Wojciechowska ◽

Ewa Sitkiewicz ◽

Agata Malinowska ◽

Bianka Świderska ◽

...

Keyword(s):

Life Cycle ◽

Developmental Stages ◽

Coupling Efficiency ◽

Slime Mold ◽

Intact Cells ◽

Life Cycle Stages ◽

Proteomic Study ◽

And Function ◽

The slime mold Dictyostelium discoideum’s life cycle includes different unicellular and multicellular stages that provide a convenient model for research concerning intracellular and intercellular mechanisms influencing mitochondria’s structure and function. We aim to determine the differences between the mitochondria isolated from the slime mold regarding its early developmental stages induced by starvation, namely the unicellular (U), aggregation (A) and streams (S) stages, at the bioenergetic and proteome levels. We measured the oxygen consumption of intact cells using the Clarke electrode and observed a distinct decrease in mitochondrial coupling capacity for stage S cells and a decrease in mitochondrial coupling efficiency for stage A and S cells. We also found changes in spare respiratory capacity. We performed a wide comparative proteomic study. During the transition from the unicellular stage to the multicellular stage, important proteomic differences occurred in stages A and S relating to the proteins of the main mitochondrial functional groups, showing characteristic tendencies that could be associated with their ongoing adaptation to starvation following cell reprogramming during the switch to gluconeogenesis. We suggest that the main mitochondrial processes are downregulated during the early developmental stages, although this needs to be verified by extending analogous studies to the next slime mold life cycle stages.