Volume changes in the early development of the golden hamster

1946 ◽  
Vol 94 (2) ◽  
pp. 129-138 ◽  
Author(s):  
John H. Venable
Keyword(s):  
Early Development ◽  
Golden Hamster ◽  
Volume Changes

Volume changes in the amniotic fluid of the golden hamster (Cricetus auratus)

1950 ◽  
Vol 106 (4) ◽  
pp. 571-575 ◽  
Author(s):  
Donald M. Purdy ◽  
Howard H. Hillemann
Keyword(s):  
Amniotic Fluid ◽  
Golden Hamster ◽  
Volume Changes

The ultrastructure of implantation in the golden hamster (Cricetus auratus)

Development ◽  
1968 ◽  
Vol 19 (3) ◽  
pp. 341-345
Author(s):  
M. P. Young ◽  
J. T. Whicher ◽  
D. M. Potts
Keyword(s):  
Early Development ◽  
Zona Pellucida ◽  
Golden Hamster ◽  
Light Microscope ◽  
Uterine Epithelium

Previous work on the early development of the golden hamster includes the investigation of Ochs (1908), Graves (1945) and Ward (1948), all at the level of the light microscope. Austin (1963) has examined the ultrastructure of the oocytes of the golden hamster while Enders & Schlafke (1965) have observed the pre-implantation stages of pregnancy. The ultrastructure of implantation has been studied in two other species of myomorph rodents: the mouse (Potts, 1966a; Reinius, 1967) and the rat (Enders & Schlafke, 1967). Implantation is taken as beginning when the zona pellucida is lost and the trophoblast is in contact with the uterine epithelium throughout its circumference. This takes place at between 80–100 h post coitum. Previous studies have been made on specimens embedded in paraffin, and the shrinkage which occurs with this method of preservation has caused implantation to appear to begin considerably later than this:Graves (1945) gives it as beginning at 5 days, Ward(1948) as 4 days 8 h.

The Time and Place of Fertilization of the Golden Hamster Egg

Development ◽  
1956 ◽  
Vol 4 (1) ◽  
pp. 42-56
Author(s):  
Fritz Strauss
Keyword(s):  
Early Development ◽  
Golden Hamster ◽  
Genital Tract ◽  
Insufficient Evidence ◽  
Male And Female ◽  
Precise Information ◽  
Induced Ovulation

There is little precise information in the literature as to the exact place where the union of the male and female gametes occurs in the genital tract of mammals. Yet it seems that an exact knowledge of the place of fertilization might be of great significance, not only for our understanding of the process of fertilization itself, but in its relation to the manifold problems associated with the limited span of time during which the capacity for fertilization persists in the sperm and egg, and to the physiology of later development and implantation. In most writings about the early development of Man and other mammals, it is assumed that the egg is fertilized in the cephalic part of the oviduct. However, there is still insufficient evidence to justify such general assumptions. It would not be surprising if it should be shown that different species have different topographical positions of the fertilization site correlated for instance with such factors as spontaneous versus induced ovulation.

scholarly journals An inverse modelling study on the local volume changes during early growth of the fetal human brain

2020 ◽  
Author(s):  
Z. Wang ◽  
B. Martin ◽  
J. Weickenmeier ◽  
K. Garikipati
Keyword(s):  
Human Brain ◽  
Early Development ◽  
Deformation Gradient ◽  
Three Dimensional ◽  
Fetal Brain ◽  
Brain Atlas ◽  
Gradient Field ◽  
Volume Changes ◽  
Local Volume ◽  
Mechanics Model

AbstractWe take a data-driven approach to deducing the local volume changes accompanying early development of the fetal human brain. Our approach uses fetal brain atlas MRI data for the geometric changes in representative cases. Using a nonlinear continuum mechanics model of morphoelastic growth, we invert the deformation field obtained from MRI registration to arrive at a field for the growth deformation gradient tensor. Our field inversion uses a combination of direct and adjoint methods for computing gradients of the objective function while constraining the optimization by the physics of morphoelastic growth. We thus infer a growth deformation gradient field that obeys the laws of morphoelastic growth. The errors between the MRI data and the forward displacement solution driven by the inverted growth deformation gradient field are found to be smaller than the reference displacement by well over an order of magnitude, and can be driven even lower. The results thus reproduce the three-dimensional growth during the early development of the fetal brain with controllable error.

Individual differences, social attention, and the history of the social motivation hypotheses of autism

2019 ◽  
Vol 42 ◽  
Author(s):  
Peter C. Mundy
Keyword(s):  
Individual Differences ◽  
Early Development ◽  
Emotional Development ◽  
Social Motivation ◽  
Social Attention ◽  
Social Emotional Development ◽  
Social Emotional ◽  
Precise Understanding ◽  
The Social ◽  
History Of

Abstract The stereotype of people with autism as unresponsive or uninterested in other people was prominent in the 1980s. However, this view of autism has steadily given way to recognition of important individual differences in the social-emotional development of affected people and a more precise understanding of the possible role social motivation has in their early development.

Classical social reward signatures in infants with later ASD

2019 ◽  
Vol 42 ◽  
Author(s):  
Teodora Gliga ◽  
Mayada Elsabbagh
Keyword(s):  
Early Development ◽  
Social Motivation ◽  
Self Report ◽  
Social Reward ◽  
Socially Motivated

Abstract Autistic individuals can be socially motivated. We disagree with the idea that self-report is sufficient to understand their social drive. Instead, we underscore evidence for typical non-verbal signatures of social reward during the early development of autistic individuals. Instead of focusing on whether or not social motivation is typical, research should investigate the factors that modulate social drives.

Early Development of Drug-Induced Hepatic Necrosis

1971 ◽  
Vol 29 ◽  
pp. 576-577
Author(s):  
F. G. Zaki ◽  
E. Detzi ◽  
C. H. Keysser
Keyword(s):  
Early Development ◽  
Hepatic Necrosis ◽  
Screening Tests ◽  
Dense Matrix ◽  
Sprague Dawley ◽  
Electron Microscopic ◽  
Drug Induced ◽  
Hepatocellular Damage ◽  
Sprague Dawley Rats ◽  
Microscopic Studies

This study represents the first in a series of investigations carried out to elucidate the mechanism(s) of early hepatocellular damage induced by drugs and other related compounds. During screening tests of CNS-active compounds in rats, it has been found that daily oral administration of one of these compounds at a dose level of 40 mg. per kg. of body weight induced diffuse massive hepatic necrosis within 7 weeks in Charles River Sprague Dawley rats of both sexes. Partial hepatectomy enhanced the development of this peculiar type of necrosis (3 weeks instead of 7) while treatment with phenobarbital prior to the administration of the drug delayed the appearance of necrosis but did not reduce its severity.Electron microscopic studies revealed that early development of this liver injury (2 days after the administration of the drug) appeared in the form of small dark osmiophilic vesicles located around the bile canaliculi of all hepatocytes (Fig. 1). These structures differed from the regular microbodies or the pericanalicular multivesicular bodies. They first appeared regularly rounded with electron dense matrix bound with a single membrane. After one week on the drug, these vesicles appeared vacuolated and resembled autophagosomes which soon developed whorls of concentric lamellae or cisterns characteristic of lysosomes (Fig. 2). These lysosomes were found, later on, scattered all over the hepatocytes.

The early development of antenna and antennal sensilla in the noctuid moth, Agrotis segetum (Insecta: Lepidoptera)

1990 ◽  
Vol 48 (3) ◽  
pp. 502-503
Author(s):  
Eric Hallberg ◽  
Lina Hansén
Keyword(s):  
Cell Death ◽  
Stem Cell ◽  
Early Development ◽  
Larval Stage ◽  
Pupal Stage ◽  
Agrotis Segetum ◽  
Antennal Sensilla ◽  
Noctuid Moth ◽  
Standard Procedures

The antennal rudiments in lepidopterous insects are present as disks during the larval stage. The tubular double-walled antennal disk is present beneath the larval antenna, and its inner layer gives rise to the adult antenna during the pupal stage. The sensilla develop from a cluster of cells that are derived from one stem cell, which gives rise to both sensory and enveloping cells. During the morphogenesis of the sensillum these cells undergo major transformations, including cell death. In the moth Agrotis segetum the pupal stage lasts about 14 days (temperature, 25°C). The antennae, clearly seen from the exterior, were dissected and fixed according to standard procedures (3 % glutaraldehyde in 0.15 M cacaodylate buffer, followed by 1 % osmiumtetroxide in the same buffer). Pupae from day 1 to day 8, of both sexes were studied.

Live Confocal Analysis of Fertilization and Early Development

2001 ◽  
Vol 7 (S2) ◽  
pp. 1012-1013
Author(s):  
Uyen Tram ◽  
William Sullivan
Keyword(s):  
Drosophila Melanogaster ◽  
Embryonic Development ◽  
Real Time ◽  
Early Development ◽  
Fluorescent Probes ◽  
Primary Defect ◽  
Fluorescent Analysis ◽  
Dynamic Event ◽  
Enormous Amount ◽  
Fluorescent Studies

Embryonic development is a dynamic event and is best studied in live animals in real time. Much of our knowledge of the early events of embryogenesis, however, comes from immunofluourescent analysis of fixed embryos. While these studies provide an enormous amount of information about the organization of different structures during development, they can give only a static glimpse of a very dynamic event. More recently real-time fluorescent studies of living embryos have become much more routine and have given new insights to how different structures and organelles (chromosomes, centrosomes, cytoskeleton, etc.) are coordinately regulated. This is in large part due to the development of commercially available fluorescent probes, GFP technology, and newly developed sensitive fluorescent microscopes. For example, live confocal fluorescent analysis proved essential in determining the primary defect in mutations that disrupt early nuclear divisions in Drosophila melanogaster. For organisms in which GPF transgenics is not available, fluorescent probes that label DNA, microtubules, and actin are available for microinjection.

Sign in / Sign up

Export Citation Format

Share Document