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Results 251 - 300 of 1021
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Cui Cheng C Department of Physics, Biocomplexity Institute, Indiana University, 727 East Third Street, Swain Hall West 159, Bloomington, IN 47405-7105, - - 2005
We have investigated the patterns of tissue flow underlying the formation of the primitive streak in the chick embryo. Analysis of time-lapse sequences of brightfield images to extract the tissue velocity field and of fluorescence images of small groups of DiI-labelled cells have shown that epiblast cells move in two ...
Delfini Marie-Claire - - 2005
The regular spacing of somites during vertebrate embryogenesis involves a dynamic gradient of FGF signaling that controls the timing of maturation of cells in the presomitic mesoderm (PSM). How the FGF signal is transduced by PSM cells is unclear. Here, we first show that the FGF gradient is translated into ...
Barna Maria - - 2005
The vertebrate limb initially develops as a bud of mesenchymal cells that subsequently aggregate in a proximal to distal (P-D) sequence to give rise to cartilage condensations that prefigure all limb skeletal components. Of the three cardinal limb axes, the mechanisms that lead to establishment and patterning of skeletal elements ...
Oates Andrew C AC Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA. - - 2005
The first morphological sign of vertebrate postcranial body segmentation is the sequential production from posterior paraxial mesoderm of blocks of cells termed somites. Each of these embryonic structures is polarized along the anterior/posterior axis, a subdivision first distinguished by marker gene expression restricted to rostral or caudal territories of forming ...
Freeman John A - - 2005
The limb of the brine shrimp Artemia develops over a four-instar period when the protopod, endite, exopod, endopod, and epipod are defined and cell differentiation (change in cell shape) occurs. To understand the importance of cell differentiation in limb growth, development of the epidermis was studied in the first thoracopod ...
Vascotto Sandy G - - 2005
Epimorphic limb regeneration in the adult newt involves the dedifferentiation of differentiated cells to yield a pluripotent blastemal cell. These mesenchymal-like cells proliferate and subsequently respond to patterning and differentiation cues to form a new limb. Understanding the dedifferentiation process requires the selective identification of dedifferentiating cells within the heterogeneous ...
Chung Hyeyoung A - - 2005
We used cDNA microarray analysis to screen for FGF target genes in Xenopus embryos treated with the FGFR1 inhibitor SU5402, and identified neurotrophin receptor homolog (NRH) as an FGF target. Causing gain of NRH function by NRH mRNA or loss of NRH function using a Morpholino antisense-oligonucleotide (Mo) led to ...
Kim Jae-Young - - 2005
Chick feather buds develop sequentially in a hexagonal array. Each feather bud develops with anterior posterior polarity, which is thought to develop in response to signals derived from specialized regions of mesenchymal condensation and epithelial thickening. These developmental processes are performed by cellular mechanisms, such as cell proliferation and migration, ...
Himeno Emi - - 2005
The role of perchloric acid-soluble protein (PSP) was investigated in chick embryos. Fluorescently labeled anti-chick liver (CL)-PSP IgG was injected into the yolk sac in ovo at embryonic day 3, and became localized in neuroepithelial cells. Within 12 h, morphological changes were observed in 37.5% of anti-CL-PSP IgG-injected embryos, and ...
Tremblay Kimberly D - - 2005
The location and movement of mammalian gut tissue progenitors, prior to the expression of tissue-specific genes, has been unknown, but this knowledge is essential to identify transitions that lead to cell type specification. To address this, we used vital dyes to label exposed anterior endoderm cells of early somite stage ...
Lopez-Sanchez Carmen - - 2005
A detailed analysis of the gastrulating chick embryo was performed using three methods : time-lapse videotaping of embryos in culture, histological semithin sections, and in situ hybridization with 10 mRNA signals expressed during gastrulation. The results suggest that the gene expression pattern of Goosecoid, Hex, Crescent, and Bmp7 may be ...
Barak Hila - - 2005
The vertebrate intermediate mesoderm (IM) is highly patterned along the anterior-posterior (A-P) axis. In the chick embryo, the kidney tissue, which is a derivative of the IM, is generated only from IM located posterior to the sixth somite axial level, which also marks the border between cranial and trunk segments. ...
Bodenstein L - - 2005
We have used a computer simulation system to examine formation of the chick primitive streak and to test the proposal (Wei and Mikawa Development 127 (2000) 87) that oriented cell division could account for primitive streak elongation. We find that this proposal is inadequate to explain elongation of the streak. ...
Echeverri Karen - - 2005
Regeneration is an ability that has been observed extensively throughout metazoan phylogeny. Amongst vertebrates, the urodele amphibians stand out for their exceptional capacity to regenerate body parts such as the limb. During this process, only the missing portion of the limb is precisely replaced--amputation in the upper arm results in ...
Gepstein Lior - - 2005
Extract: Recent advances in molecular and cellular biology and specifically in the areas of stem cell biology and tissue engineering have paved the way for the development of a new field in biomedicine, regenerative medicine. This exciting approach seeks to develop new biological solutions, using the mobilization of endogenous stem ...
Takahashi Yu - - 2005
Mesp1 and Mesp2 are homologous basic helix-loop-helix (bHLH) transcription factors that are co-expressed in the anterior presomitic mesoderm (PSM) just prior to somite formation. Analysis of possible functional redundancy of Mesp1 and Mesp2 has been prevented by the early developmental arrest of Mesp1/Mesp2 double-null embryos. Here we performed chimera analysis, ...
Morán María Genoveva González - - 2005
The aim of this study was to detect the presence of estrogen receptor alpha in different cell subpopulations of the growing left and regressing right ovaries from newly hatched chicks, by immunohistochemical methods, using an indirect immunoperoxidase technique. Newly hatched chicks were killed by decapitation and the growing left and ...
Ng Elizabeth S - - 2005
The homeobox gene Mixl1 is expressed in the primitive streak of the gastrulating embryo, and marks cells destined to form mesoderm and endoderm. The role of Mixl1 in development of haematopoietic mesoderm was investigated by analysing the differentiation of ES cells in which GFP was targeted to one (Mixl1(GFP/w)) or ...
Madhavan, Mayur C
Hundreds of millions of people across the world suffer from severely impaired vision and as the population of the world grows older, this problem will become more severe. One avenue of therapy for these patients may be to induce healthy cells of the eye to regenerate cells that may be ...
Rappazzo Giancarlo - - 2005
Massive apoptosis of mesenchymal cells in the septum of the aortico-pulmonary trunk was found in mouse fetuses at stage 14.5dpc. It was associated with the appearance of cavities in the mesenchymal tissue, presumably due to cell loss, a strong reduction in the extent of lectin PNA staining, and the induction ...
Xiao-Feng Pang P Inst. of Life Sci. & Technol., Univ. of Electron. Sci. & Technol. of China, - - 2005
The influences of the carbon nanotubes on proliferation state of chick embryo fibroblast cells and toxicity of the nanotubes to the cells have been investigated by 3-(4,5-dimethylthiazol 2-yl)-2,5 diphenylte-trazolium bromide (MTT) colorimetric method of Mosmann and the toxicology. We found that the toxicity of the carbon nanotubes to the chick ...
Naito Jumpei - - 2004
On average, in chicks, the total number of retinal ganglion cells is 4.9 x 10(6) and the cell density is 10400 cells/mm2. Two high-density areas, namely the central area (CA) and the dorsal area (DA), are located in the central and dorsal retinas, respectively, in post-hatching day 8 (P8) chicks ...
Lammers Andrew R - - 2004
Effects of substrate diameter on locomotor biodynamics were studied in the gray short-tailed opossum (Monodelphis domestica). Two horizontal substrates were used: a flat 'terrestrial' trackway with a force platform integrated into the surface and a cylindrical 'arboreal' trackway (20.3 mm diameter) with a force-transducer instrumented region. On both terrestrial and ...
Ogita Shinjiro - - 2004
In vitro culture of hypocotyl explants from Kandelia candel, a common mangrove species, on hormone-free Murashige and Skoog (MS) medium resulted in shoot formation. Since the hypocotyls showed good potential for in vitro shoot multiplication, the process of bud primordium formation was analyzed from a histological viewpoint. A wound periderm ...
Lu Cindy C - - 2004
The TGFbeta family member Nodal has been shown to be involved in a variety of processes in development, including early axis formation. Here, we use a conditional gene inactivation strategy to show a specific requirement for Nodal in the epiblast. Complete inactivation of the Nodal locus in the epiblast using ...
Hatcher Cathy J - - 2004
Transcriptional regulatory cascades during epicardial and coronary vascular development from proepicardial progenitor cells remain to be defined. We have used immunohistochemistry of human embryonic tissues to demonstrate that the TBX5 transcription factor is expressed not only in the myocardium, but also throughout the embryonic epicardium and coronary vasculature. TBX5 is ...
Shim W - - 2004
Congestive heart failure (CHF) remains the most common diagnosis made in cardiology wards today. No long-term therapeutic option for end-stage CHF is available except for orthotopic heart transplant. Cellular-based therapy has emerged as a potential new therapy for patients with advanced heart failure. Different cell types are being explored in ...
Brabham, Kori Vasser
Due to mechanical loading, cartilage experiences distortional change, volumetric change, and fluid flow. Research has shown cells to be responsive to unconfined compression, a load that produces all three conditions. To isolate the factor(s) responsible for chondrogenesis, the first goal of this research was to design and implement a device ...
Gros Jérôme - - 2004
The study of the morphogenetic cell movements underlying myotome formation in the chick embryo has led to the emergence of highly controversial models. Here we report a real-time cell lineage analysis of myotome development using electroporation of a GFP reporter in newly formed chick somites. Confocal analysis of cell movements ...
Chen Y - - 2004
Changes in cell density and size in the ganglion cell layer (GCL) of the retina were studied in chick embryos and post-hatching chicks. The total number of cells in the GCL increased from 3.64 million at embryonic day 8 (E8) to the maximal 7.85 million at E14. After E14, the ...
Smallhorn Masha - - 2004
Drosophila pebble (pbl) encodes a Rho-family GTP exchange factor (GEF) required for cytokinesis. The accumulation of high levels of PBL protein during interphase and the developmentally regulated expression of pbl in mesodermal tissues suggested that the primary cytokinetic mutant phenotype might be masking other roles. Using various muscle differentiation markers, ...
Schumacher Sabine - - 2004
The FGF receptor Heartless (HTL) is required for mesodermal cell migration in the Drosophila gastrula. We show that mesoderm cells undergo different phases of specific cell shape changes during mesoderm migration. During the migratory phase, the cells adhere to the basal surface of the ectoderm and exhibit extensive protrusive activity. ...
Brudzynski Katrina - - 2004
Caffeic acid phenethyl ester (CAPE), a natural compound of bee propolis, selectively inhibits proliferation of transformed cells in several cancer models in vitro. To examine in vivo CAPE function, we used the newt regeneration blastema as a model system wherein the processes of de-differentiation and subsequent proliferation of undifferentiated cells ...
Leise Walter F WF - - 2004
Coordination of morphogenesis and cell proliferation is essential during development. In Xenopus, cell divisions are rapid and synchronous early in development but then slow and become spatially restricted during gastrulation and neurulation. One tissue that transiently stops dividing is the paraxial mesoderm, a dynamically mobile tissue that forms the somites ...
Van Stry Melanie - - 2004
Platelet-derived growth factor receptor (PDGFR) signaling is required for normal gastrulation in Xenopus laevis. Embryos deprived of PDGFR signaling develop with a range of gastrulation-specific defects including spina bifida, shortened anteroposterior axis, and reduced anterior structures. These defects arise because the involuting mesoderm fails to move appropriately. In this study, ...
Schweizer H - - 2004
Limb buds develop from lateral plate-derived stationary mesenchyme and are invaded by cells from extrinsic regions. The largest populations of these cells are myogenic precursor cells that originate from the lateral dermomyotomes. After detachment under the influence of SF/HGF, myogenic precursor cells migrate in a proximo-distal direction and populate a ...
Wilson Sylvia M - - 2004
Experimental metastasis assays are used to measure the ability of cancer cells to grow in secondary organs following injection of the cells into the circulation of an experimental animal. The chicken embryo provides an alternative to the more commonly used assays in mice. Details of the experimental metastasis assay in ...
Kajstura Jan - - 2004
Adult ventricular myocytes can undergo mitotic division, resulting in an increase in the aggregate number of cells in the heart. The improvement in the methodological approach to the analysis of tissue sections by immunostaining and confocal microscopy has defeated the dogma that myocyte regeneration cannot occur in the adult heart. ...
Drenhaus U - - 2004
This study focused on the temporal and spatial pattern of expression of the cell adhesion molecule axonin-1 in amacrine cells and the identification of these cells in the developing chick retina. We analyzed 5-20-day-old chick embryos. The antigen was localized and visualized by the indirect immunogold and the immunofluorescence technique. ...
Fléchon Jacques-E - - 2004
The epithelial versus mesenchymal phenotypes of embryonic ectoderm and mesoderm cells of the prestreak stage pig embryos were examined by electron microscopy and molecular marker analysis. During this period the embryonic disc remained flat or slightly convex while becoming oval or pyriform in shape. Mesenchyme cells expressing vimentin were present ...
Stocum D L - - 2004
Larval and adult urodeles and anuran tadpoles readily regenerate their limbs via a process of histolysis and dedifferentiation of mature cells local to the amputation surface that accumulate under the wound epithelium as a blastema of stem cells. These stem cells require growth and trophic factors from the apical epidermal ...
Fritz-Six Kimberly L - - 2003
Tropomodulin1 (Tmod1) caps thin filament pointed ends in striated muscle, where it controls filament lengths by regulating actin dynamics. Here, we investigated myofibril assembly and heart development in a Tmod1 knockout mouse. In the absence of Tmod1, embryonic development appeared normal up to embryonic day (E) 8.5. By E9.5, heart ...
Sari Youssef - - 2003
Besides neuronal transmission, serotonin (5-HT) also acts as a trophic signal during the development of the central nervous and neural crest systems. In this study, we report that in addition to trophic effect, 5-HT increases the proliferation of fetal heart cells. We showed for the first time that the cultured ...
Guo Qiuxia - - 2003
The apical ectodermal ridge (AER) is a critical signaling center at the tip of the limb that promotes outgrowth. In mouse, formation of the AER involves a gradual restriction of AER gene expression from a broad ventral preAER domain to the tip of the limb, as well as progressive thickening ...
Giampaoli S - - 2003
Limb regenerative potential in urodeles seems to vary among different species. We observed that Triturus vulgaris meridionalis regenerate their limbs significantly faster than T. carnifex, where a long gap between the time of amputation and blastema formation occurs, and tried to identify cellular and molecular events that may underlie these ...
Zikova Martina - - 2003
Specification of bilateral cardiac primordia and formation of the linear heart tube are highly conserved from Drosophila to humans. However, subsequent heart morphogenesis involving nonmesodermal neural crest cells was thought to be specific for vertebrates. Here, we provide evidence that a group of nonmesodermal cells that we have named heart-anchoring ...
Méndez M C - - 2003
Previous studies have demonstrated that FSH stimulates cell proliferation in the ovary and the testis of the chick embryo. This study analyzed the presence of FSH receptor and the cell subpopulations that proliferate in response to FSH in chick embryo gonads. FSH receptor mRNA was detected by reverse transcription-polymerase chain ...
Robertson Elizabeth J - - 2003
Prior to gastrulation the mouse embryo exists as a symmetrical cylinder consisting of three tissue layers. Positioning of the future anterior-posterior axis of the embryo occurs through coordinated cell movements that rotate a pre-existing proximal-distal (P-D) axis. Overt axis formation becomes evident when a discrete population of proximal epiblast cells ...
Plachta Nicolas - - 2003
Endogenous nitric oxide (NO) has recently been shown to affect cell cycle progression in the neural tube (NT) of the chick embryo. High NO levels trigger entry into S phase basally, while low NO levels facilitate mitosis apically. Here, we further explore the involvement of NO in determining cell numbers ...
Anakwe Kelly - - 2003
The limb musculature arises by delamination of premyogenic cells from the lateral dermomyotome. Initially the cells express Pax3 but, upon entering the limb bud, they switch on the expression of MyoD and Myf5 and undergo terminal differentiation into slow or fast fibres, which have distinct contractile properties that determine how ...
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