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Henry C A - - 2000
In vertebrates, paraxial mesoderm is partitioned into repeating units called somites. It is thought that the mechanical forces arising from compaction of the presumptive internal cells of prospective somites cause them to detach from the unsegmented presomitic mesoderm [1-3]. To determine how prospective somites physically segregate from each other, we ...
Huang R - - 2000
Bones of the postcranial skeleton of higher vertebrates originate from either somitic mesoderm or somatopleural layer of the lateral plate mesoderm. Controversy surrounds the origin of the scapula, a major component of the shoulder girdle, with both somitic and lateral plate origins being proposed. Abnormal scapular development has been described ...
Domingo C - - 2000
During gastrulation, the vertebrate embryo is patterned and shaped by complex signaling pathways and morphogenetic movements. One of the first regions defined during gastrulation is the prospective notochord, which exhibits specific cell behaviors that drive the extension of the embryonic axis. To examine the signals involved in notochord formation in ...
Ward E J - - 2000
The odd-skipped (odd) gene encodes a zinc finger protein that represses other segmentation genes in the early Drosophila embryo. Though odd is initially expressed in a striped pattern that reflects its function within the segmentation hierarchy, it is also expressed in a variety of patterns during later stages of embryogenesis. ...
Keller R - - 2000
The cells of many embryonic tissues actively narrow in one dimension (convergence) and lengthen in the perpendicular dimension (extension). Convergence and extension are ubiquitous and important tissue movements in metazoan morphogenesis. In vertebrates, the dorsal axial and paraxial mesodermal tissues, the notochordal and somitic mesoderm, converge and extend. In amphibians ...
Kim G J - - 2000
The major mesodermal tissues of ascidian larvae are muscle, notochord and mesenchyme. They are derived from the marginal zone surrounding the endoderm area in the vegetal hemisphere. Muscle fate is specified by localized ooplasmic determinants, whereas specification of notochord and mesenchyme requires inducing signals from endoderm at the 32-cell stage. ...
Omi M - - 2000
In the developing chick leg bud, massive programmed cell death occurs in the interdigital region. Previously, we reported the inhibition of cell death by separation of the interdigital region from neighboring digit cartilage. In this study, we examined the relationship between cell death and cartilaginous tissue in vitro. First, cell ...
Patwardhan V - - 2000
During chick embryogenesis, cells destined to form cardiac myocytes are located within the primitive streak at stage 3 in the same relative anterior-posterior distribution as in the prelooped heart. The most rostral cells contribute to the extreme anterior pole of the heart, the bulbus cordis, and the most caudal to ...
Cazorla O - - 2000
In vivo the sub-epicardial myocardium (EPI) and sub-endocardial myocardium (ENDO) operate over different ranges of sarcomere length (SL). However, it has not been previously shown whether EPI and ENDO work upon different ranges of the same or differing length-tension curves. We have compared the SL-tension relationship of intact, single ventricular ...
Painter K J - - 2000
The formation of the primitive streak in early avian development marks the onset of gastrulation, during which large scale cell movement leads to a trilaminar blastoderm comprising prospective endodermal, mesodermal and ectodermal tissue. During streak formation a specialized group of cells first moves anteriorly as a coherent column, beginning from ...
Narasimha M - - 2000
The conversion of an epithelial monolayer into a multilayered structure consisting of the three germ layers, ectoderm, mesoderm and endoderm, constitutes a conserved theme in the early development of animals. This is accomplished by morphogenetic movements that occur during gastrulation and serve not only to generate shape but also to ...
Lough J - - 2000
Since the first half of the 20th century, experimental embryologists have noted a relationship between endoderm cells and the development of cardiac tissue from mesoderm. During the past decade, the accumulation of evidence for an obligatory interaction between endoderm and mesoderm during the specification and terminal differentiation of myocardial, and ...
Cossmann P H - - 2000
Chromatin morphology of interphase nuclei in most cell lines of quail (Coturnix coturnix japonica) and chick (Gallus gallus domesticus) embryos shows typical interspecies differences. This intrinsic marker has been used in quail/chick chimerisation experiments, where also differences between cell types were noted. We asked whether similar differences between species and ...
Espinar A - - 2000
This work investigated the ability of melatonin to prevent cell damage in the cerebellar cortex of chick embryo caused by glutamate administration. Cell injury was evaluated estimating, at ultrastructural level, the phenomenon of cell death and the synaptogenesis of the Purkinje cells and the cerebellar glomerular synaptic complex. Administration of ...
Yan R T - - 2000
Coaxing plastic, non-neuronal cells to transdifferentiate into a particular type of neurons might have clinical applications. Previously we reported that neuroD induces transdifferentiation of retinal pigment epithelium (RPE) cells derived from day-6 chick embryos into cells that resemble young photoreceptor cells. These cells also express visinin, a gene expressed early ...
Carmona R - - 2000
Slug is a transcription factor involved in processes such as the formation of mesoderm and neural crest, two developmental events that imply a transition from an epithelial to a mesenchymal phenotype. During late cardiac morphogenesis, mesenchymal cells originate from two epithelia--epicardial mesothelium and cushion endocardium. We aimed to check if ...
A. G. Pillay
A chronological, quantitative light microscopic investigation on the histogenic organisation and behaviour of the trigeminal-ganglion was carried out in the ontogeny of the chick. Embryos of 24 chicks at embryonic days 6 - 18 (E6 - E18), on the day of hatching (H) and adult (A) were processed. Paraffin sections ...
Wei Y - - 2000
Gastrulation in the amniote begins with the formation of a primitive streak through which precursors of definitive mesoderm and endoderm ingress and migrate to their embryonic destinations. This organizing center for amniote gastrulation is induced by signal(s) from the posterior margin of the blastodisc. The mode of action of these ...
Tickle C - - 2000
Limb development is an excellent model for studying how patterns of differentiated cells and tissues are generated in vertebrate embryos. The cell interactions that mediate patterning have been discovered and, more recently, some of the molecules involved in these interactions have been identified. This has provided a direct link to ...
Kishi H - - 2000
Protein kinases are involved in a variety of cellular functions and cell proliferation in eyes. We have explored the involvement of protein kinase C (PKC) in cell proliferation and melanin synthesis by chick retinal pigment epithelial (RPE) cells in vitro. This was achieved by incubation of confluent RPE cells with ...
Zanin M K - - 1999
Although chondroitin sulfate proteoglycans (CSPGs) are major components of the embryonic extracellular matrix, little attention has been paid to specific CSPGs in early heart development, in part because appropriate antibodies were not available. Therefore we prepared specific polyclonal antibodies against chicken aggrecan, versican, neurocan, and phosphacan. Western blotting and immunohistochemical ...
Ji A - - 1999
The CHO cell line stably producing recombinant rat NT-3 was established. The insertion of rNT-3 cDNA into transferred cell gonome was analyzed with Southern blot. The expressed protein was identified by Dot ELISA (enzyme-linked immunosorbent assay) and Western blot. Western blot showed a clear specific band of about 14 ku ...
Gustavsson L M - - 1999
The male genital duct in Tubificidae consists of a funnel, a vas deferens, an atrium, and, frequently, a copulatory structure. There may also be a diffuse or compact prostate gland in association with the duct. The morphogenesis of this duct is described for Rhyacodrilus coccineus and Monopylephorus rubroniveus (Rhyacodrilinae). The ...
Barrio-Asensio C - - 1999
The ontogenic development of the sphincter iris has been studied by immunocytochemistry and standard staining on chick embryos from stage 25 HH to the time of hatching. We have used the monoclonal antibody 13F4, a highly specific marker of muscular cells. We have observed three different regions in the iris. ...
Marí-Beffa M - - 1999
The results obtained using morphometric variables which describe fin ray regeneration patterns are reported for individual fin ray amputations in the goldfish (Carassius auratus) and zebrafish (Brachydanio rerio). Classical and updated experiments are compared to verify previous morphogenetic models of cell tractions (Oster et al. 1983) or epidermis-mesenchyme induction (Saunders ...
Ting A C - - 1999
To define the role of air plethysmography (APG) in the clinical diagnosis and quantitative assessment of chronic venous insufficiency (CVI), APG studies were performed on 582 limbs in 291 patients with signs and symptoms of CVI. One hundred and thirty-one limbs were classified into group I (no evidence of CVI), ...
Joubin K - - 1999
The organizer is a unique region in the gastrulating embryo that induces and patterns the body axis. It arises before gastrulation under the influence of the Nieuwkoop center. We show that during gastrulation, cell movements bring cells into and out of the chick organizer, Hensen's node. During these movements, cells ...
Tsubokawa R - - 1999
Cell death was characterized during stages 8 and 9 in the leech Helobdella with a modified terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling method. Using confocal analysis, the positions of dying cells were compared to rows of cells expressing the leech engrailed protein ht-en and to fluorescently marked cell lineages. ...
Wolpert L - - 1999
To understand limb abnormalities it is necessary to understand how the limb develops. The limb is the organ whose development is probably best understood. The limbs develop from small protrusions (the limb buds) that arise from the body wall of the embryo. Positioning and patterning the limb involves cellular interactions ...
Park H O - - 1999
Yeast cells of different cell type exhibit distinct budding patterns that reflect the organization of the actin cytoskeleton. Bud1p (Rsr1p), a Ras-like GTPase, and Bud2p, a GTPase-activating protein for Bud1p, are essential for proper budding pattern. We show that Bud2p is localized at the presumptive bud site in G(1) cells ...
Schlage W K - - 1999
Of the various in vitro invasion assays described, only a few use tissues as substrates, for example, the chick heart fragment assay and the chick embryo skin (CES) invasion assay (Noguchi et al., 1978). We have improved culture conditions for the CES invasion assay (Schlage, 1989). A suspension of neoplastically ...
Saga Y - - 1999
The Mesp1 gene encodes the basic HLH protein MesP1 which is expressed in the mesodermal cell lineage during early gastrulation. Disruption of the Mesp1 gene leads to aberrant heart morphogenesis, resulting in cardia bifida. In order to study the defects in Mesp1-expressing cells during gastrulation and in the specification of ...
Li S - - 1999
Experiments have been carried out to investigate the role of the apical ectodermal ridge (AER) and FGF-4 on the control of cell migration during limb bud morphogenesis. By coupling DiI cell labeling with ectopic implantation of FGF-4 microcarrier beads we have found that FGF-4 acts as a potent and specific ...
Li C M - - 1999
cNSCL1 is the chick homologue of mammalian NSCL1, a basic helix-loop-helix gene transiently expressed during neurogenesis. To gain insight into its function, we studied the involvement of cNSCL1 in retinal neurogenesis. In situ hybridization showed dynamic, cell-type-specific expression of cNSCL1, first in developing ganglion cells and later in glial cells. ...
Kobayashi C - - 1999
To understand the cellular events during planarian regeneration, we analyzed the process of pharynx regeneration in both head and tail pieces using cell-type-specific markers. Interestingly, cells expressing the pharynx-muscle-specific myosin heavy chain gene (DjMHC-A) appeared within 24 h after amputation (prior to the formation of a pharynx rudiment) in the ...
Goto A - - 1999
Annelids are strongly segmented animals that display a high degree of metamerism in their body plan. The embryonic origin of metameric segmentation was examined in an oligochaete annelid Tubifex using lineage tracers. Segmental organization arises sequentially in the anterior-to-posterior direction along the longitudinal axis of the mesodermal germ band, a ...
Keyes W M - - 1999
The incidence of apoptotic cells in the hearts of chick embryos between days 4 and 8 of development was examined using an in situ technique for the detection of DNA fragmentation. Using this method it was possible to demonstrate foci of apoptotic cells primarily in two locations: the outflow tract ...
Bollag R J - - 1999
Monitoring the migrations of cells during embryonic development requires a system in which cells can be identified in situ during locomotion. One promising system involves the generation of chimeras by transplanting mouse cells into chick embryos in ovo to exploit the wealth of mouse genetic variants. The success of this ...
Macias D - - 1999
Embryonic limb outgrowth is accomplished by the proliferation of mesodermal cells in the progress zone. In this region, mesodermal cells are maintained in an undifferentiated and proliferating state by the action of the apical ectodermal ridge (AER). Differentiation of these cells into individual skeletal elements occurs when the cells are ...
Shiga T - - 1999
The relationship between the appearance of Islet-1-expressing cells and the longitudinal growth of primary afferent axons (PAAs) in the dorsal spinal cord of chick embryos was examined. Islet-1-expressing cells first appeared in the dorsal spinal cord at embryonic days (E) 3-3.5. These immunoreactive cells were aligned in a longitudinal column ...
Koibuchi N - - 1999
During vertebrate limb development, the limb bud grows along the proximo-distal (P-D) direction, with the cells changing their adhesiveness. To know whether the position-related differences in cell adhesiveness are actually utilized by morphogenesis to constitute limb structures, we grafted cell aggregates made of dissociated cells derived from different positions and ...
Choy M - - 1999
Abnormalities of the cushion tissues lead to atrioventricular septal defects (AVSD) and truncus arteriosus (TA). Bisdiamine exposure in the embryo frequently causes AVSD and TA in the newborn chick, mouse, or rat. We studied the effects of bisdiamine on mesenchymal cells grown in aggregate culture isolated from the developing atrioventricular ...
Warga R M - - 1999
The segregation of cells into germ layers is one of the earliest events in the establishment of cell fate in the embryo. In the zebrafish, endoderm and mesoderm are derived from cells that involute into an internal layer, the hypoblast, whereas ectoderm is derived from cells that remain in the ...
Satoh F - - 1999
A case of multiple myeloma, who died of congestive heart failure of unknown cause, is presented. Microscopically, Anitschkow cells with caterpillar and owl-eyed nuclei were scattered in the interstitium of the myocardium. To know the pathological significance of their appearance, histological observations of normal, developing and autoimmune disease-bearing heart specimens ...
Dale K - - 1999
Ventral midline cells in the neural tube have distinct properties at different rostrocaudal levels, apparently in response to differential signalling by axial mesoderm. Floor plate cells are induced by sonic hedgehog (SHH) secreted from the notochord whereas ventral midline cells of the rostral diencephalon (RDVM cells) appear to be induced ...
Luchman H A - - 1999
The er1 gene is a novel fibroblast growth factor (FGF)-regulated immediate-early gene, first isolated from Xenopus blastulae, that encodes a nuclear protein with potent transcription transactivational activity (Paterno et al., 1997). We report here the expression pattern of the ER1 protein during Xenopus embryonic development. ER1 protein is present in ...
Breen J G - - 1999
Epidemiologic studies strongly suggest that in utero exposure to hyperthermia results in developmental defects in humans. Rats, mice, guinea pigs, and other species exposed to hyperthermia also exhibit a variety of developmental defects. Studies in our laboratory have focused on exposure to hyperthermia on Gestation Day (GD) 10 of rats ...
Kawasaki Y - - 1999
The effect of nitric oxide (NO) on the contractile tone of Müller cells was investigated. Müller cells, isolated from the retina of chick embryos, were cultured on thin sheets of silicone. S-Nitro-N-acetyl-DL-penicillamine (SNAP), an NO donor, was applied in the presence or the absence of carboxyl phenyltetramethylimidazole oxide (C-PTIO), an ...
Warga R M - - 1998
The dorsal marginal zone of the zebrafish blastula, equivalent to the amphibian Spemann organizer, is destined to become the tissues of the notochord and prechordal plate. Preceding gastrulation in the zebrafish, we find that these future mesendodermal cells acquire a cohesive cell behavior characterized by flattening and maximization of intercellular ...
Kahane N - - 1998
We have shown that a subset of early postmitotic progenitors that originates along the medial part of the epithelial somite gives rise to the primary myotome (Kahane, N., Cinnamon, Y. and Kalcheim, C. (1998). Mech. Dev. 74, 59-73). Because of its postmitotic nature, further myotome expansion must be achieved by ...
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