Changes in cell dimensions and intercellular contacts during cleavage-stage cycles in mouse embryonic cells

Development ◽  
1980 ◽  
Vol 58 (1) ◽  
pp. 231-249
Author(s):  
E. Lehtonen
Keyword(s):  
Surface Area ◽  
Time Lapse ◽  
Parental Cell ◽  
Embryonic Cells ◽  
Cell Stage ◽  
Cell Pair ◽  
Daughter Cells ◽  
Cell Dimensions ◽  
Intercellular Contacts ◽  
The Relationship

The cleavage behaviour of cells isolated from 1- to 8-cell-stage mouse embryos was studied with time-lapse video equipment; changes in cellular dimensions and their timing were recorded. The division of an isolated cell results in the formation of a twin-cell pair. The divisions of these two cells were always asynchronous. In each division the volume of a daughter cell was approximately half of that of the parental cell but its apparent surface area was 59-65% of that of the parental cell. Consequently, the ratio of apparent surface area to volume increased in each division by 25-30%. The most noticeable changes were observed in the relationship between the two daughter cells of each division. After cytokinesis, the intercellular contact area gradually increased during the following cell cycle in the 2/8- and 2/16-cell pairs, whereas it hardly changed in the 2/2- and 2/4-cell pairs. The comparison of the behaviour of the daughter cells on different substrates suggested that the zona pellucida and the mid body might have a role in the contact development at the early stages. Scanning electron microscopy was used for studying changes in the density of cell surface microvilli in an attempt to explain how the cells regulate their intercellular contacts.

scholarly journals Dynamics of cytoplasm and cleavage divisions correlates with preimplantation embryo development

Reproduction ◽  
2018 ◽  
Vol 155 (1) ◽  
pp. 1-14 ◽  
Author(s):  
Robert Milewski ◽  
Marcin Szpila ◽  
Anna Ajduk
Keyword(s):  
Time Lapse ◽  
Preimplantation Development ◽  
Embryonic Cells ◽  
High Quality ◽  
Cell Stage ◽  
Preimplantation Embryo Development ◽  
Non Invasive ◽  
Image Velocimetry ◽  
Time Lapse Imaging

In vitrofertilization has become increasingly popular as an infertility treatment. In order to improve efficiency of this procedure, there is a strong need for a refinement of existing embryo assessment methods and development of novel, robust and non-invasive selection protocols. Studies conducted on animal models can be extremely helpful here, as they allow for more extensive research on the potential biomarkers of embryo quality. In the present paper, we subjected mouse embryos to non-invasive time-lapse imaging and combined the Particle Image Velocimetry analysis of cytoplasmic dynamics in freshly fertilized oocytes with the morphokinetic analysis of recordings covering 5 days of preimplantation development. Our results indicate that parameters describing cytoplasmic dynamics and cleavage divisions independently correspond to mouse embryo’s capacity to form a high-quality blastocyst. We also showed for the first time that these parameters are associated with the percentage of abnormal embryonic cells with fragmented nuclei and with embryo’s ability to form primitive endoderm, one of the cell lineages differentiated during preimplantation development. Finally, we present a model that links selected cytoplasmic and morphokinetic parameters reflecting frequency of fertilization-induced Ca2+-oscillations and timing of 4-cell stage and compaction with viability of the embryo assessed as the total number of cells at the end of its preimplantation development. Our results indicate that a combined analysis of cytoplasmic dynamics and morphokinetics may facilitate the assessment of embryo’s ability to form high-quality blastocysts.

Polygonal networks in living chick embryonic cells

1981 ◽  
Vol 52 (1) ◽  
pp. 55-69
Author(s):  
G.W. Ireland ◽  
F.C. Voon
Keyword(s):  
Dorsal Surface ◽  
Time Lapse ◽  
Cell Types ◽  
Outer Edge ◽  
Live Cells ◽  
Embryonic Cells ◽  
Embryo Cells ◽  
Dissociated Cells ◽  
The Relationship ◽  
Free Edges

Regular polygonal networks have been found in explants and dissociated cells of early chick embryos. These networks are readily observable in live cells with phase-contrast optics thus allowing time-lapse cinemicroscopy. They consisted of a regular pattern of nodes and radiating struts found predominantly in the lamelliplasm of the free edges of the cells bordering explants. At the outer edge, the network was terminated by radial struts associated with substrate-attached retraction processes whilst toward the centre of the cells it faded out. The network was also associated with stress fibres running across the cell and with microextensions on the dorsal surface. Even within one cell the network varied in size. Time-lapse films showed that microvilli were protruded from the dorsal surface over the nodes. Although the cells containing the networks were poorly motile the network itself was a mobile structure. Many explants from regions differing in prospective fates developed these networks after 2–4 days in culture. They appeared earlier in the smaller less yolky cells of definitive endoblast and epiblast. Experiments with dissociated and reaggregated cells confirmed their occurrence mainly in free edges of cells. The relationship between these networks seen in living chick embryo cells and those seen in other cell types using immunofluorescent techniques is discussed and a mechanism is proposed for their formation.

Changes in the distribution of membranous organelles during mouse early development

Development ◽  
1985 ◽  
Vol 90 (1) ◽  
pp. 287-309
Author(s):  
Bernard Maro ◽  
Martin H. Johnson ◽  
Susan J. Pickering ◽  
Daniel Louvard
Keyword(s):  
Endoplasmic Reticulum ◽  
Basolateral Membrane ◽  
Early Embryo ◽  
Apical Region ◽  
Basal Region ◽  
Embryonic Cells ◽  
Cell Stage ◽  
Surface Phenotype ◽  
Daughter Cells ◽  
Differentiated Cells

The unfertilized oocyte, fertilized egg and early embryo (2-cell to 16-cell) of the mouse have been examined immunocytochemically for the distribution of antigens associated with the endoplasmic reticulum, the lysosomal and acidic vesicle fraction (100kD antigen), Golgi apparatus (135kD antigen) and coated vesicles (clathrin). The distribution of these antigens has also been examined in isolated 8-cell and 16-cell-stage blastomeres of various ages and phenotypes. Endoplasmic reticulum is detected only weakly in the oocyte and egg, but is seen abundantly at later stages both in association with the nuclear membrane and evenly distributed throughout the cytoplasm, except in regions of cell: cell apposition from which it is excluded. Intracellular clathrin is associated with the spindle in mitotic and meiotic cells. During interphase, clathrin is distributed throughout the cell until the mid-8-cell stage when it is concentrated into the apical region of the cell under the region of membrane at which a surface pole of microvilli will form subsequently. Thus, the cytoplasmic polarization of clathrin precedes overt polarization at the surface. At mitosis, the clathrin relocates to the spindle and is distributed to both daughter cells. It resumes an apical location beneath the surface pole of microvilli in polar daughter 1/16 cells, but remains dispersed in apolar daughter 1/16 cells. Both the lysosomal and Golgi antigens are distributed throughout the cytoplasm until the early 16-cell stage. In pairs of 16-cell blastomeres both antigens aggregate in a single cluster and do so whether the surface phenotype of the blastomeres is polar or apolar. The position of this cluster is not consistently related to the point of contact with the other cell in the pair but there is a suggestion that in cells with a polar surface phenotype the polar foci of Golgi/lysosomal antigens are located between the nucleus and the surface pole at earlier time points, but shift to a position between the basolateral membrane and the nucleus at the later time point. In intact 16-cell embryos also, the aggregated Golgi/lysosomal antigens of polar cells appear to localize to the basal region. The distributions of these various organelles in embryonic cells reported here show a number of differences from those reported previously for mature, differentiated cells.

The use of Body Surface Index as a Better Clinical Health indicators Compare to Body Mass Index and Body Surface Area for Clinical Application

2018 ◽  
pp. 131-136
Author(s):  
Shirazu I. ◽  
Theophilus. A. Sackey ◽  
Elvis K. Tiburu ◽  
Mensah Y. B. ◽  
Forson A.
Keyword(s):  
Surface Area ◽  
Body Surface Area ◽  
Clinical Application ◽  
Body Surface ◽  
Body Height ◽  
Health Indicators ◽  
The Body ◽  
Body Parameters ◽  
The Relationship ◽  
Individual Body

The relationship between body height and body weight has been described by using various terms. Notable among them is the body mass index, body surface area, body shape index and body surface index. In clinical setting the first descriptive parameter is the BMI scale, which provides information about whether an individual body weight is proportionate to the body height. Since the development of BMI, two other body parameters have been developed in an attempt to determine the relationship between body height and weight. These are the body surface area (BSA) and body surface index (BSI). Generally, these body parameters are described as clinical health indicators that described how healthy an individual body response to the other internal organs. The aim of the study is to discuss the use of BSI as a better clinical health indicator for preclinical assessment of body-organ/tissue relationship. Hence organ health condition as against other body composition. In addition the study is `also to determine the best body parameter the best predict other parameters for clinical application. The model parameters are presented as; modeled height and weight; modelled BSI and BSA, BSI and BMI and modeled BSA and BMI. The models are presented as clinical application software for comfortable working process and designed as GUI and CAD for use in clinical application.

The relationship between brain structure and general psychopathology in preadolescents

2020 ◽  
Author(s):  
Louise Mewton ◽  
Briana Lees ◽  
Lindsay Squeglia ◽  
Miriam K. Forbes ◽  
Matthew Sunderland ◽  
...  
Keyword(s):  
Mental Disorders ◽  
Surface Area ◽  
Brain Structure ◽  
Parental Education ◽  
Mental Illnesses ◽  
General Psychopathology ◽  
Control Approach ◽  
Cortical Volume ◽  
Subcortical Regions ◽  
The Relationship

Categorical mental disorders are being recognized as suboptimal targets in clinical neuroscience due to poor reliability as well as high rates of heterogeneity within, and comorbidity between, mental disorders. As an alternative to the case-control approach, recent studies have focused on the relationship between neurobiology and latent dimensions of psychopathology. The current study aimed to investigate the relationship between brain structure and psychopathology in the critical preadolescent period when psychopathology is emerging. This study included baseline data from the Adolescent Brain and Cognitive Development (ABCD) Study® (n = 11,721; age range = 9-10 years; male = 52.2%). General psychopathology, externalizing, internalizing, and thought disorder dimensions were based on a higher-order model of psychopathology and estimated using Bayesian plausible values. Outcome variables included global and regional cortical volume, thickness, and surface area. Higher levels of psychopathology across all dimensions were associated with lower volume and surface area globally, as well as widespread and pervasive alterations across the majority of cortical and subcortical regions studied, after adjusting for sex, race/ethnicity, and parental education. The relationships between general psychopathology and brain structure were attenuated when adjusting for cognitive functioning. There was evidence of a relationship between externalizing psychopathology and frontal regions of the cortex that was independent of general psychopathology. The current study identified lower cortical volume and surface area as transdiagnostic biomarkers for general psychopathology in preadolescence. The widespread and pervasive relationships between general psychopathology and brain structure may reflect cognitive dysfunction that is a feature across a range of mental illnesses.

Anaphase Movements in the Living Cell

1948 ◽  
Vol 25 (1) ◽  
pp. 45-72 ◽  
Author(s):  
A. F. HUGHES ◽  
M. M. SWANN
Keyword(s):  
Fibre Length ◽  
Polarized Light ◽  
Embryonic Cells ◽  
Contractile Mechanism ◽  
Spindle Poles ◽  
Chromosome Separation ◽  
Relationship Of ◽  
The Relationship ◽  
Chromosome Movements ◽  
Spindle Fibres

1. The anaphase movements of living embryonic cells of the chick in tissue culture have been studied in phase contrast illumination, and in polarized light. Ciné-photographic records of chromosome movements and spindle changes have thereby been obtained simultaneously. 2. Chromosome separation in the chick is made up of two components--a movement of chromosomes towards the spindle poles, and an elongation of the spindle as a whole. 3. The assumption is made that the force acting on a chromosome is directly proportional to the velocity with which the chromosome moves. If this assumption is accepted as an approximation, it is possible to interpret the relationship of chromosome velocity to chromosome separation and spindle-fibre length. This leads to the conclusion that anaphase movement is due, not to repulsion between chromosomes, but to a contractile mechanism operating from the spindle poles. 4. Polarized light studies indicate that the orientation of the spindle material is high at the poles, and weaker at the equator. There is a small aster at either end of the spindle. 5. The centrosomes are interpreted as centres of an orienting force, which build up the contractile mechanism of the spindle from isotropic protoplasm. It is suggested that asters may also be contractile, and cause elongation of the spindle. 6. The inadequacy of the old conception of spindle fibres is discussed in the light of more modern views on molecular behaviour.

Conditioning of a culture substratum by the ectodermal layer promotes attachment and oriented locomotion by amphibian gastrula mesodermal cells

1983 ◽  
Vol 59 (1) ◽  
pp. 43-60 ◽  
Author(s):  
N. Nakatsuji ◽  
K.E. Johnson
Keyword(s):  
Cell Migration ◽  
Time Lapse ◽  
Ambystoma Maculatum ◽  
Specific Cell ◽  
Animal Pole ◽  
Micron Diameter ◽  
The Relationship ◽  
Extracellular Fibrils ◽  
Scanning Electron

We have found that ectodermal fragments of Ambystoma maculatum gastrulae deposit immense numbers of 0.1 micron diameter extracellular fibrils on plastic coverslips. When migrating mesodermal cells from A. maculatum gastrulae are seeded on such conditioned plastic substrata, they attach and begin migrating after 15–30 min in vitro. We did a detailed analysis of the relationship between fibril orientation and cell migration using time-lapse cinemicrography, scanning electron microscopy, and a microcomputer with a graphics tablet and morphometric program. We found that cells move in directions closely related to the orientation of fibrils. Usually fibrils are oriented in dense arrays with a predominance of fibrils running parallel to the blastopore-animal pole axis of the explant, and cells move preferentially along lines parallel to the blastopore-animal pole axis. When fibrils are unaligned, cells move at random. We have also shown that cells move with a slightly stronger tendency towards the animal pole direction. These results are discussed concerning the mechanism of specific cell migration during amphibian gastrulation.

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